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Sample records for eliminating mercury removal

  1. IMPACT OF ELIMINATING MERCURY REMOVAL PRETREATMENT ON THE PERFORMANCE OF A HIGH LEVEL RADIOACTIVE WASTE MELTER OFFGAS SYSTEM

    SciTech Connect

    Zamecnik, J; Alexander Choi, A

    2009-03-17

    The Defense Waste Processing Facility at the Savannah River Site processes high-level radioactive waste from the processing of nuclear materials that contains dissolved and precipitated metals and radionuclides. Vitrification of this waste into borosilicate glass for ultimate disposal at a geologic repository involves chemically modifying the waste to make it compatible with the glass melter system. Pretreatment steps include removal of excess aluminum by dissolution and washing, and processing with formic and nitric acids to: (1) adjust the reduction-oxidation (redox) potential in the glass melter to reduce radionuclide volatility and improve melt rate; (2) adjust feed rheology; and (3) reduce by steam stripping the amount of mercury that must be processed in the melter. Elimination of formic acid pretreatment has been proposed to eliminate the production of hydrogen in the pretreatment systems; alternative reductants would be used to control redox. However, elimination of formic acid would result in significantly more mercury in the melter feed; the current specification is no more than 0.45 wt%, while the maximum expected prior to pretreatment is about 2.5 wt%. An engineering study has been undertaken to estimate the effects of eliminating mercury removal on the melter offgas system performance. A homogeneous gas-phase oxidation model and an aqueous phase model were developed to study the speciation of mercury in the DWPF melter offgas system. The model was calibrated against available experimental data and then applied to DWPF conditions. The gas-phase model predicted the Hg{sub 2}{sup 2-}/Hg{sup 2+} ratio accurately, but some un-oxidized Hg{sup 0} remained. The aqueous model, with the addition of less than 1 mM Cl{sub 2} showed that this remaining Hg{sup 0} would be oxidized such that the final Hg{sub 2}{sup 2+}/Hg{sup 2+} ratios matched the experimental data. The results of applying the model to DWPF show that due to excessive shortage of chloride, only 6% of

  2. Mercury removal sorbents

    DOEpatents

    Alptekin, Gokhan

    2016-03-29

    Sorbents and methods of using them for removing mercury from flue gases over a wide range of temperatures are disclosed. Sorbent materials of this invention comprise oxy- or hydroxyl-halogen (chlorides and bromides) of manganese, copper and calcium as the active phase for Hg.sup.0 oxidation, and are dispersed on a high surface porous supports. In addition to the powder activated carbons (PACs), this support material can be comprised of commercial ceramic supports such as silica (SiO.sub.2), alumina (Al.sub.2O.sub.3), zeolites and clays. The support material may also comprise of oxides of various metals such as iron, manganese, and calcium. The non-carbon sorbents of the invention can be easily injected into the flue gas and recovered in the Particulate Control Device (PCD) along with the fly ash without altering the properties of the by-product fly ash enabling its use as a cement additive. Sorbent materials of this invention effectively remove both elemental and oxidized forms of mercury from flue gases and can be used at elevated temperatures. The sorbent combines an oxidation catalyst and a sorbent in the same particle to both oxidize the mercury and then immobilize it.

  3. Eliminating Mercury Thermometers from the Lab.

    ERIC Educational Resources Information Center

    Everett, T. Stephen

    1997-01-01

    Compares the precision, accuracy, and response of a cooking probe to a standard mercury thermometer in side-by-side heating in temperature baths, simple and fractional distillations, and melting point determination. (DDR)

  4. Biomodification of coal to remove mercury

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A biological process for removal of mercury from coal is under investigation. Iron and sulfur oxidizing bacteria have previously been used for desulfurization of coal and for mineral mining. We have shown that removal of mercury from coal is also possible via the same principles. Two pure culture...

  5. Sorbents for mercury removal from flue gas

    SciTech Connect

    Granite, Evan J.; Hargis, Richard A.; Pennline, Henry W.

    1998-01-01

    A review of the various promoters and sorbents examined for the removal of mercury from flue gas is presented. Commercial sorbent processes are described along with the chemistry of the various sorbent-mercury interactions. Novel sorbents for removing mercury from flue gas are suggested. Since activated carbons are expensive, alternate sorbents and/or improved activated carbons are needed. Because of their lower cost, sorbent development work can focus on base metal oxides and halides. Additionally, the long-term sequestration of the mercury on the sorbent needs to be addressed. Contacting methods between the flue gas and the sorbent also merit investigation.

  6. Elemental mercury removal using a wet scrubber

    SciTech Connect

    Martin, K.; Gonzalez, E.; Zhou, C.Q.; Livengood, C.D.; Mendelsohn, M.H.

    1999-11-01

    Mercury (Hg) is a toxic metal that is emitted into the environment by both natural and human activities. Acute and chronic exposure to mercury and methyl mercury in humans results in central nervous system damage, kidney damage, and even death. Although some Hg emission sources have been regulated, coal-fired utilities have not been. In anticipation of federal regulations on mercury emissions from coal fired power plants, Argonne National Laboratory (ANL) has designed a flue gas simulation system to study the removal of elemental mercury. The simulated flue gas enters the system and combines with the inlet mercury vapor (from a calibrated permeation tube), carried by nitrogen gas. This combined gas continues past the flow meter and the pressure gage to the reactor inlet. Inside the reactor chamber, the flue gas is sprayed with NOXSORB{reg_sign} a chloric acid solution, which reacts with elemental mercury. The amount of reaction (oxidation) of elemental mercury is important since mercury in an oxidized form is highly soluble. In this form the Hg can be picked up downstream by a wet scrubber. Experiments on mercury removal from flue gases have been conducted at ANL, with the participation of a senior design team from Purdue University Calumet. A literature survey on the current and proposed mercury control legislation, along with the existing control technologies has been performed as part of the senior design project. The experimental results obtained at Argonne will be related to existing wet scrubber technology to determine the economic feasibility of mercury removal. A cost per pound of mercury analysis will be utilized.

  7. Process for removing mercury from aqueous solutions

    DOEpatents

    Googin, John M.; Napier, John M.; Makarewicz, Mark A.; Meredith, Paul F.

    1986-01-01

    A process for removing mercury from water to a level not greater than two parts per billion wherein an anion exchange material that is insoluble in water is contacted first with a sulfide containing compound and second with a compound containing a bivalent metal ion forming an insoluble metal sulfide. To this treated exchange material is contacted water containing mercury. The water containing not more than two parts per billion of mercury is separated from the exchange material.

  8. Process for removing mercury from aqueous solutions

    DOEpatents

    Googin, J.M.; Napier, J.M.; Makarewicz, M.A.; Meredith, P.F.

    1985-03-04

    A process for removing mercury from water to a level not greater than two parts per billion wherein an anion exchange material that is insoluble in water is contacted first with a sulfide containing compound and second with a compound containing a bivalent metal ion forming an insoluble metal sulfide. To this treated exchange material is contacted water containing mercury. The water containing not more than two parts per billion of mercury is separated from the exchange material.

  9. Removal of mercury by adsorption: a review.

    PubMed

    Yu, Jin-Gang; Yue, Bao-Yu; Wu, Xiong-Wei; Liu, Qi; Jiao, Fei-Peng; Jiang, Xin-Yu; Chen, Xiao-Qing

    2016-03-01

    Due to natural and production activities, mercury contamination has become one of the major environmental problems over the world. Mercury contamination is a serious threat to human health. Among the existing technologies available for mercury pollution control, the adsorption process can get excellent separation effects and has been further studied. This review is attempted to cover a wide range of adsorbents that were developed for the removal of mercury from the year 2011. Various adsorbents, including the latest adsorbents, are presented along with highlighting and discussing the key advancements on their preparation, modification technologies, and strategies. By comparing their adsorption capacities, it is evident from the literature survey that some adsorbents have shown excellent potential for the removal of mercury. However, there is still a need to develop novel, efficient adsorbents with low cost, high stability, and easy production and manufacture for practical utility. PMID:26620868

  10. Method for the removal and recovery of mercury

    DOEpatents

    Easterly, C.E.; Vass, A.A.; Tyndall, R.L.

    1997-01-28

    The present invention is an enhanced method for the removal and recovery of mercury from mercury-contaminated matrices. The method involves contacting a mercury-contaminated matrix with an aqueous dispersant solution derived from specific intra-amoebic isolates to release the mercury from the mercury-contaminated matrix and emulsify the mercury; then, contacting the matrix with an amalgamating metal from a metal source to amalgamate the mercury to the amalgamating metal; removing the metallic source from the mercury-contaminated matrix; and heating the metallic source to vaporize the mercury in a closed system to capture the mercury vapors.

  11. Method for the removal and recovery of mercury

    DOEpatents

    Easterly, Clay E.; Vass, Arpad A.; Tyndall, Richard L.

    1997-01-01

    The present invention is an enhanced method for the removal and recovery of mercury from mercury-contaminated matrices. The method involves contacting a mercury-contaminated matrix with an aqueous dispersant solution derived from specific intra-amoebic isolates to release the mercury from the mercury-contaminated matrix and emulsify the mercury; then, contacting the matrix with an amalgamating metal from a metal source to amalgamate the mercury to the amalgamating metal; removing the metallic source from the mercury-contaminated matrix; and heating the metallic source to vaporize the mercury in a closed system to capture the mercury vapors.

  12. Elemental mercury removal using a wet scrubber.

    SciTech Connect

    Gonzalez, E.; Livengood, C. D.; Martin, K.; Mendelsohn, M. H.; Zhou, C. Q.

    1999-05-19

    Mercury (Hg) is a toxic metal that is emitted into the environment by both natural and human activities. Acute and chronic exposure to mercury and methyl mercury in humans results in central nervous system damage, kidney damage, and even death. Although some Hg emission sources have been regulated, coal-fired utilities have not been. In anticipation of federal regulations on mercury emissions from coal-fired power plants, Argonne National Laboratory (ANL) has designed a flue gas simulation system to study the removal of elemental mercury. The simulated flue gas enters the system and combines with the inlet mercury vapor (from a calibrated permeation tube), carried by nitrogen gas. This combined gas continues past the flow meter and the pressure gage to the reactor inlet. Inside the reactor chamber, the flue gas is sprayed with NOXSORB{reg_sign}, a chloric acid solution, which reacts with elemental mercury. The amount of reaction (oxidation) of elemental mercury is important since mercury in an oxidized form is highly soluble, In this form, the Hg can be picked up downstream by a wet scrubber from fossil-fuel burning utilities. Experiments on mercury removal from flue gases have been conducted at ANL, with the participation of a senior design team from Purdue University Calumet. Temperature variations ranging from room temperature to 350 F have been studied. Other parameters, such as the concentration of NOXSORB{reg_sign}, were also tested. Furthermore, pump speed and sprayer droplet sizes of the NOXSORB{reg_sign} solution were studied. A literature survey on the current and proposed mercury control legislation, along with the existing control technologies, has been performed as part of the senior design project. With guidance from ANL, an understanding of the simulation system has been developed. This information has been used to determine the mass transfer. Another literature survey was performed on the reaction kinetics of mercury. The information obtained was

  13. Mercury elimination rates for adult northern pike Esox lucius: evidence for a sex effect

    USGS Publications Warehouse

    Madenjian, Charles P.; Blanchfield, Paul J.; Hrenchuk, Lee E.; Van Walleghem, Jillian L. A.

    2014-01-01

    We examined the effect of sex on mercury elimination in fish by monitoring isotope-enriched mercury concentrations in the muscle tissue of three adult female and three adult male northern pike Esox lucius, which had accumulated the isotope-enriched mercury via a whole-lake manipulation and were subsequently moved to a clean lake. Mercury elimination rates for female and male northern pike were estimated to be 0.00034 and 0.00073 day−1, respectively. Thus, males were capable of eliminating mercury at more than double the rate than that of females. To the best of our knowledge, our study represents the first documentation of mercury elimination rates varying between the sexes of fish. This sex difference in elimination rates should be taken into account when comparing mercury accumulation between the sexes of fish from the same population. Further, our findings should eventually lead to an improved understanding of mechanisms responsible for mercury elimination in vertebrates.

  14. Removal of mercury from soil with earthworms

    SciTech Connect

    Dorfman, D.

    1994-12-31

    Earthworms can live in soils containing high quantities of mercury, lead, and zinc. The worms (Lumbricus terrestris) concentrate these heavy metals in their tissues. The use of these worms to reduce the quantities of mercury and other heavy metals in soils may be practical. In July, 1993, a preliminary study was made using earthworms and soils with differing amounts of mercury, The quantities were 0.0 grams, 0.5 grams, and 1.0 grams of mercury as mercuric chloride. Earthworms were placed into these soils for two or more weeks, then harvested. The worms were rinsed with deionized water, then dissolved in nitric acid. Each sample was prepared for analysis with the addition of HNO{sub 3}, H{sub 2}SO{sub 4}, potassium permanganate, and hydrozylamine hydrochloride. A Jerome Instrument gold foil analyzer was used to determine levels of mercury after volatilizing the sample with stannous chloride. Worms exposed to contaminated soils remove 50 to 1,400 times as much mercury as do worms in control soils. In a hypothetical case, a site contaminated with one pound of mercury, 1,000 to 45,000 worms would be required to reduce mercury levels to background levels in the soil (about 250 ppb). After harvesting worms in contaminated soil they could be dried (90% of their weight is water), and the mercury regained by chemical processes. Soil conducive to earthworm survival is required. This includes a well aerated loamy soil, proper pH (7.0), and periodic watering and feeding. There are several methods of harvesting worms, including flooding and electricity. Large numbers of worms can be obtained from commercial growers.

  15. Using Wet-FGD systems for mercury removal.

    PubMed

    Díaz-Somoano, Mercedes; Unterberger, Sven; Hein, Klaus R G

    2005-09-01

    A plan to control mercury emissions to the atmosphere and to establish mercury emission limits has recently been elaborated by the European Commission, making it necessary to devise an efficient and cost effective mercury removal technology. Towards this end wet flue gas desulfurization units appear as a promising option for multi-pollutant control. However, more investigation on mercury removal and a greater mercury removal efficiency are required to achieve this objective. In the present work scrubber chemistry and the application of various solid additives to enhance mercury removal in wet scrubbers is evaluated. The results obtained show a significant correlation between mercury removal efficiency and the pH of the scrubber slurry and SO2 concentration. A weaker correlation was observed between oxygen or slurry concentration and removal efficiency. Finally several solid oxides were found to be effective additives for enhancing mercury capture in wet scrubbers. PMID:16121271

  16. Method for removal and stabilization of mercury in mercury-containing gas streams

    DOEpatents

    Broderick, Thomas E.

    2005-09-13

    The present invention is directed to a process and apparatus for removing and stabilizing mercury from mercury-containing gas streams. A gas stream containing vapor phase elemental and/or speciated mercury is contacted with reagent, such as an oxygen-containing oxidant, in a liquid environment to form a mercury-containing precipitate. The mercury-containing precipitate is kept or placed in solution and reacts with one or more additional reagents to form a solid, stable mercury-containing compound.

  17. Results of Small-Scale Tests for Removing Mercury from ORNL Process Wastewater

    SciTech Connect

    Taylor, P.A.; Klasson, K.T.

    1999-06-01

    Oak Ridge National Laboratory (ORNL) received a new National Pollutant Discharge Elimination System (NPDES) Permit from the state of Tennessee in 1997. This permit reduced the limit for mercury in the effluent from the Process Wastewater Treatment Complex - Building 3608 (PWTC-3608) to 19 ppt for the monthly average, which is well below the current effluent concentration. The mercury limit is being appealed, so it is not currently being enforced, but experimental work is being done to determine if it is possible to meet this new limit. Various mercury sorbents were evaluated in small, continuous-flow columns. The first set of sorbent tests that were conducted at PWTC-3608 in August 1997 showed excellent mercury removal by the Forager Sponge, even at high flow rates. Subsequent tests, however, showed that the mercury removal by the Forager Sponge, even at high flow rates. Subsequent tests, however, showed that the mercury removal efficiency of the sorbents varied considerably over time, probably as a result of changes in the form of the mercury in the wastewater. A significant portion of the mercury in PWTC-3608 water was bound to small particles during the later tests, which made the mercury less accessible to the sorbents. Chlorination of the water, which could convert the mercury to an ionic form, improved the performance of some of the sorbents.

  18. Sorbents for the oxidation and removal of mercury

    DOEpatents

    Olson, Edwin S.; Holmes, Michael J.; Pavlish, John H.

    2008-10-14

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  19. Sorbents for the oxidation and removal of mercury

    DOEpatents

    Olson, Edwin S.; Holmes, Michael J.; Pavlish, John H.

    2012-05-01

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  20. Sorbents for the oxidation and removal of mercury

    DOEpatents

    Olson, Edwin S.; Holmes, Michael J.; Pavlish, John Henry

    2014-09-02

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  1. Eliminating iodine deficiency: obstacles and their removal.

    PubMed

    Padilla, Carmencita David; Fagela-Domingo, Carmelita

    2008-12-01

    Iodine deficiency remains a global concern for developing countries and some industrialised countries. Iodine deficiency is the most common cause of preventable mental retardation, posing a threat to the social and economic development of countries. Initiatives were developed and instituted to accelerate progress to achieve the goal of universal salt iodisation (USI). However, these efforts were not successful in eliminating iodine deficiency disorders (IDD) in some countries. Every year, 50 million children are born without the protection that iodine offers to the growing brain and body and about 18 million suffer some significant degree of mental impairment. The World Health Organization (WHO), United Nations Children's Fund (UNICEF) and non-governmental organisations assist to ensure that populations at risk have access to iodised salt. This paper will review the highlights of iodine deficiency and present the experiences in the various countries in Asia, i.e. assessments of the situation, action plans, and obstacles to implementation. PMID:19904447

  2. Removal of mercury from coal via a microbial pretreatment process

    DOEpatents

    Borole, Abhijeet P.; Hamilton, Choo Y.

    2011-08-16

    A process for the removal of mercury from coal prior to combustion is disclosed. The process is based on use of microorganisms to oxidize iron, sulfur and other species binding mercury within the coal, followed by volatilization of mercury by the microorganisms. The microorganisms are from a class of iron and/or sulfur oxidizing bacteria. The process involves contacting coal with the bacteria in a batch or continuous manner. The mercury is first solubilized from the coal, followed by microbial reduction to elemental mercury, which is stripped off by sparging gas and captured by a mercury recovery unit, giving mercury-free coal. The mercury can be recovered in pure form from the sorbents via additional processing.

  3. REMOVAL OF MERCURY FROM COAL-DERIVED SYNTHESIS GAS

    SciTech Connect

    Tom Barton

    2006-03-01

    The reduction of mercury emission from fossil fuel applications is an increasing priority for the US power industry due to regulatory pressure. While mercury removal during combustion is well studied, mercury removal in gasification is less so. The increasing application of coal gasification in future plant designs supplies the incentive for more study of mercury removal gasification processes. In gasification where the mercury is expected to be elemental, activated carbon injection has been the most effective method of mercury removal. Absorption of elemental mercury at high temperature has not been shown to be effective. The carbon is best injected downstream where the temperature has moderated and an independent collector can be established. Experiments have been conducted at 400 F to compare mercury absorption on activated carbon as received and ''super'' activated carbon. The ''super'' activated carbon was prepared by soaking the carbon in 6M nitric acid followed by neutralization and washing. Each absorption experiment has been run for 16 hours of exposure time to the gasifier product stream. The carbon samples were tested for mercury absorption by ICP hydride generation. The two carbon samples which had been washed in nitric acid then exposed to the gasifier slipstream showed higher concentrations of mercury even at this elevated absorption temperature when compared to the as received activated carbon.

  4. Thiacrown polymers for removal of mercury from waste streams

    DOEpatents

    Baumann, Theodore F.; Reynolds, John G.; Fox, Glenn A.

    2002-01-01

    Thiacrown polymers immobilized to a polystyrene-divinylbenzene matrix react with Hg.sup.2+ under a variety of conditions to efficiently and selectively remove Hg.sup.2+ ions from acidic aqueous solutions, even in the presence of a variety of other metal ions. The mercury can be recovered and the polymer regenerated. This mercury removal method has utility in the treatment of industrial wastewater, where a selective and cost-effective removal process is required.

  5. Thiacrown polymers for removal of mercury from waste streams

    DOEpatents

    Baumann, Theodore F.; Reynolds, John G.; Fox, Glenn A.

    2004-02-24

    Thiacrown polymers immobilized to a polystyrene-divinylbenzene matrix react with Hg.sup.2+ under a variety of conditions to efficiently and selectively remove Hg.sup.2+ ions from acidic aqueous solutions, even in the presence of a variety of other metal ions. The mercury can be recovered and the polymer regenerated. This mercury removal method has utility in the treatment of industrial wastewater, where a selective and cost-effective removal process is required.

  6. Removal of Mercury from Coal-Derived Synthesis Gas

    SciTech Connect

    2005-09-29

    A paper study was completed to survey literature, patents, and companies for mercury removal technologies applicable to gasification technologies. The objective was to determine if mercury emissions from gasification of coal are more or less difficult to manage than those from a combustion system. The purpose of the study was to define the extent of the mercury problem for gasification-based coal utilization and conversion systems. It is clear that in coal combustion systems, the speciation of mercury between elemental vapor and oxidized forms depends on a number of factors. The most important speciation factors are the concentration of chlorides in the coal, the temperatures in the ducting, and residence times. The collection of all the mercury was most dependent upon the extent of carbon in the fly ash, and the presence of a wet gas desulfurization system. In combustion, high chloride content plus long residence times at intermediate temperatures leads to oxidation of the mercury. The mercury is then captured in the wet gas desulfurization system and in the fly ash as HgCl{sub 2}. Without chloride, the mercury oxidizes much slower, but still may be trapped on thick bag house deposits. Addition of limestone to remove sulfur may trap additional mercury in the slag. In gasification where the mercury is expected to be elemental, activated carbon injection has been the most effective method of mercury removal. The carbon is best injected downstream where temperatures have moderated and an independent collector can be established. Concentrations of mercury sorbent need to be 10,000 to 20,000 the concentrations of the mercury. Pretreatment of the activated carbon may include acidification or promotion by sulfur.

  7. Mercury removal in utility wet scrubber using a chelating agent

    DOEpatents

    Amrhein, Gerald T.

    2001-01-01

    A method for capturing and reducing the mercury content of an industrial flue gas such as that produced in the combustion of a fossil fuel or solid waste adds a chelating agent, such as ethylenediaminetetraacetic acid (EDTA) or other similar compounds like HEDTA, DTPA and/or NTA, to the flue gas being scrubbed in a wet scrubber used in the industrial process. The chelating agent prevents the reduction of oxidized mercury to elemental mercury, thereby increasing the mercury removal efficiency of the wet scrubber. Exemplary tests on inlet and outlet mercury concentration in an industrial flue gas were performed without and with EDTA addition. Without EDTA, mercury removal totaled 42%. With EDTA, mercury removal increased to 71%. The invention may be readily adapted to known wet scrubber systems and it specifically provides for the removal of unwanted mercury both by supplying S.sup.2- ions to convert Hg.sup.2+ ions into mercuric sulfide (HgS) and by supplying a chelating agent to sequester other ions, including but not limited to Fe.sup.2+ ions, which could otherwise induce the unwanted reduction of Hg.sup.2+ to the form, Hg.sup.0.

  8. Method for removal of mercury from various gas streams

    DOEpatents

    Granite, E.J.; Pennline, H.W.

    2003-06-10

    The invention provides for a method for removing elemental mercury from a fluid, the method comprising irradiating the mercury with light having a wavelength of approximately 254 nm. The method is implemented in situ at various fuel combustion locations such as power plants and municipal incinerators.

  9. Treatment of radioactive laboratory waste for mercury removal

    SciTech Connect

    Osteen, A.B.; Bibler, J.P.

    1990-01-01

    Routine analyses of Savannah River Laboratory wastes at the Savannah River Site occasionally reveal mercury concentrations in the waste in excess of the 0.200 {mu}g/L RCRA limit. An ion exchange resin has been demonstrated to be effective for the removal of dissolved mercury from laboratory waste in a special permitted project. The ion exchange material is Duolite{trademark} GT-73, a polystyrene/divinylbenzene resin with thiol functional groups. As a result of the decontamination demonstration, the resin is in use or under consideration for use with several other SRS radwaste streams as a reliable medium for mercury removal.

  10. Treatment of radioactive laboratory waste for mercury removal. Revision 1

    SciTech Connect

    Osteen, A.B.; Bibler, J.P.

    1990-12-31

    Routine analyses of Savannah River Laboratory wastes at the Savannah River Site occasionally reveal mercury concentrations in the waste in excess of the 0.200 {mu}g/L RCRA limit. An ion exchange resin has been demonstrated to be effective for the removal of dissolved mercury from laboratory waste in a special permitted project. The ion exchange material is Duolite{trademark} GT-73, a polystyrene/divinylbenzene resin with thiol functional groups. As a result of the decontamination demonstration, the resin is in use or under consideration for use with several other SRS radwaste streams as a reliable medium for mercury removal.

  11. Mercury nano-trap for effective and efficient removal of mercury(II) from aqueous solution.

    PubMed

    Li, Baiyan; Zhang, Yiming; Ma, Dingxuan; Shi, Zhan; Ma, Shengqian

    2014-01-01

    Highly effective and highly efficient decontamination of mercury from aqueous media remains a serious task for public health and ecosystem protection. Here we report that this task can be addressed by creating a mercury 'nano-trap' as illustrated by functionalizing a high surface area and robust porous organic polymer with a high density of strong mercury chelating groups. The resultant porous organic polymer-based mercury 'nano-trap' exhibits a record-high saturation mercury uptake capacity of over 1,000 mg g(-1), and can effectively reduce the mercury(II) concentration from 10 p.p.m. to the extremely low level of smaller than 0.4 p.p.b. well below the acceptable limits in drinking water standards (2 p.p.b.), and can also efficiently remove >99.9% mercury(II) within a few minutes. Our work therefore presents a new benchmark for mercury adsorbent materials and provides a new perspective for removing mercury(II) and also other heavy metal ions from contaminated water for environmental remediation. PMID:25410491

  12. Mercury vapour exposure during dental student training in amalgam removal

    PubMed Central

    2013-01-01

    Background Amalgam that is used for dental fillings contains approximately 50% elemental mercury. During dental student training, amalgam is often removed by drilling without the use of water spray and suction, which are protective measures in preventing mercury aerosol. In this study we measured mercury vapor levels in ambient air during amalgam removal as is typically performed in dental training. Methods Mercury vapor levels in ambient air were measured in a dental school laboratory during removal of amalgam fillings from artificial teeth set into a dental jaw simulator. Mercury vapor was measured under three conditions (25 measurements each): with the simultaneous use of water spray and suction, with the use of suction only, and with the use of neither suction nor water spray. These three conditions are all used during dental student training. Results were compared to Alberta occupational exposure limits for mercury vapor in order to assess potential occupational risk to students. Analysis of variance testing was used to compare data obtained under the three conditions. Results When water spray and suction were used, mercury vapor levels ranged from 4.0 to 19.0 μg/m3 (arithmetic mean = 8.0 μg/m3); when suction only was used, mercury vapor levels ranged from 14.0 to 999.0 (999.0 μg/m3 represents the high limit detection of the Jerome analyzer) (arithmetic mean = 141.0 μg/m3); when neither suction nor water was used, the vapor levels ranged from 34.0 to 796.0 μg/m3 (arithmetic mean = 214.0 μg/m3). Conclusions The Alberta Occupational Health and Safety threshold limit value for mercury vapor over an eight-hour time-weighted period is 25.0 μg/m3. The absolute ceiling for mercury vapor, not to be exceeded at any time, is 125.0 μg/m3. When both water spray and suction were used, mercury vapor levels were consistently below this threshold. When suction without water spray was used, mercury vapor levels exceeded the safety threshold 8% of

  13. Removal of mercury from chloralkali electrolysis wastewater by a mercury-resistant Pseudomonas putida strain

    SciTech Connect

    Canstein, H. von; Li, Y.; Timmis, K.N.; Deckwer, W.D.; Wagner-Doebler, I.

    1999-12-01

    A mercury-resistant bacterial strain which is able to reduce ionic mercury to metallic mercury was used to remediate in laboratory columns mercury-containing wastewater produced during electrolytic production of chlorine. Factory effluents from several chloralkali plants in Europe were analyzed, and these effluents contained total mercury concentrations between 1.6 and 7.6 mg/liter and high chloride concentrations and had pH values which were either acidic or alkaline. A mercury-resistant bacterial strain, Pseudomonas putida Spi3, was isolated from polluted river sediments. Biofilms of P.putida Spi3 were grown on porous carrier material in laboratory column bioreactors. The bioreactors were continuously fed with sterile synthetic model wastewater or nonsterile, neutralized, aerated chloralkali wastewater. The authors found that sodium chloride concentrations up to 24 g/liter did not inhibit microbial mercury retention and that mercury concentrations up to 7 mg/liter could be treated with the bacterial biofilm with no loss of activity. When wastewater samples from three different chloralkali plants in Europe were used, levels of mercury retention efficiency between 90 and 98% were obtained. Thus, microbial mercury removal is a potential biological treatment for chloralkali electrolysis wastewater.

  14. Removal of Mercury from Chloralkali Electrolysis Wastewater by a Mercury-Resistant Pseudomonas putida Strain

    PubMed Central

    von Canstein, H.; Li, Y.; Timmis, K. N.; Deckwer, W.-D.; Wagner-Döbler, I.

    1999-01-01

    A mercury-resistant bacterial strain which is able to reduce ionic mercury to metallic mercury was used to remediate in laboratory columns mercury-containing wastewater produced during electrolytic production of chlorine. Factory effluents from several chloralkali plants in Europe were analyzed, and these effluents contained total mercury concentrations between 1.6 and 7.6 mg/liter and high chloride concentrations (up to 25 g/liter) and had pH values which were either acidic (pH 2.4) or alkaline (pH 13.0). A mercury-resistant bacterial strain, Pseudomonas putida Spi3, was isolated from polluted river sediments. Biofilms of P. putida Spi3 were grown on porous carrier material in laboratory column bioreactors. The bioreactors were continuously fed with sterile synthetic model wastewater or nonsterile, neutralized, aerated chloralkali wastewater. We found that sodium chloride concentrations up to 24 g/liter did not inhibit microbial mercury retention and that mercury concentrations up to 7 mg/liter could be treated with the bacterial biofilm with no loss of activity. When wastewater samples from three different chloralkali plants in Europe were used, levels of mercury retention efficiency between 90 and 98% were obtained. Thus, microbial mercury removal is a potential biological treatment for chloralkali electrolysis wastewater. PMID:10583977

  15. Isotopic fractionation during the uptake and elimination of inorganic mercury by a marine fish.

    PubMed

    Xu, Xiaoyu; Wang, Wen-Xiong

    2015-11-01

    This study investigated the mass dependent (MDF) and independent fractionation (MIF) of stable mercury isotopes in fish during the uptake and elimination of inorganic species. Mercury accumulation during the exposure led to re-equilibration of organ isotopic compositions with the external sources, and elimination terminated the equilibrating with isotope ratios moving back to the original values. Generally, the isotopic behaviors corresponded to the changes of Hg accumulation in the muscle and liver, causing by the internal transportation, organ redistribution, and mixing of different sources. A small degree of MDF caused by biotransformation of Hg in the liver was documented during the elimination, whereas MIF was not observed. The absence of MIF during geochemical and metabolic processes suggested that mercury isotopes can be used as source tracers. Additionally, fish liver is a more responsive organ than muscle to track Hg source when it is mainly composed of inorganic species. PMID:26184584

  16. Removal of mercury from an alumina refinery aqueous stream.

    PubMed

    Mullett, Mark; Tardio, James; Bhargava, Suresh; Dobbs, Charles

    2007-06-01

    Digestion condensate is formed as a by-product of the alumina refinery digestion process. The solution exhibits a high pH and is chemically reducing, containing many volatile species such as water, volatile organics, ammonia, and mercury. Because digestion condensate is chemically unique, an innovative approach was required to investigate mercury removal. The mercury capacity and adsorption kinetics were investigated using a number of materials including gold, silver and sulphur impregnated silica and a silver impregnated carbon. The results were compared to commercial sorbents, including extruded and powdered virgin activated carbons and a sulphur impregnated mineral. Nano-gold supported on silica (88% removal under batch conditions and 95% removal under flow conditions) and powdered activated carbon (91% under batch conditions and 98% removal under flow conditions) were the most effective materials investigated. The silver and sulphur impregnated materials were unstable in digestion condensate under the test conditions used. PMID:17123705

  17. Removal of Mercury by Foam Fractionation Using Surfactin, a Biosurfactant

    PubMed Central

    Chen, Hau-Ren; Chen, Chien-Cheng; Reddy, A. Satyanarayana; Chen, Chien-Yen; Li, Wun Rong; Tseng, Min-Jen; Liu, Hung-Tsan; Pan, Wei; Maity, Jyoti Prakash; Atla, Shashi B.

    2011-01-01

    The separation of mercury ions from artificially contaminated water by the foam fractionation process using a biosurfactant (surfactin) and chemical surfactants (SDS and Tween-80) was investigated in this study. Parameters such as surfactant and mercury concentration, pH, foam volume, and digestion time were varied and their effects on the efficiency of mercury removal were investigated. The recovery efficiency of mercury ions was highly sensitive to the concentration of the surfactant. The highest mercury ion recovery by surfactin was obtained using a surfactin concentration of 10 × CMC, while recovery using SDS required < 10 × CMC and Tween-80 >10 × CMC. However, the enrichment of mercury ions in the foam was superior with surfactin, the mercury enrichment value corresponding to the highest metal recovery (10.4%) by surfactin being 1.53. Dilute solutions (2-mg L−1 Hg2+) resulted in better separation (36.4%), while concentrated solutions (100 mg L−1) enabled only a 2.3% recovery using surfactin. An increase in the digestion time of the metal solution with surfactin yielded better separation as compared with a freshly-prepared solution, and an increase in the airflow rate increased bubble production, resulting in higher metal recovery but low enrichment. Basic solutions yielded higher mercury separation as compared with acidic solutions due to the precipitation of surfactin under acidic conditions. PMID:22174661

  18. Removal of mercury from stack gases by activated carbon

    SciTech Connect

    Vidic, R.D.

    1995-10-01

    On combustion, the trace elements in the incinerator feed stream are partitioned between the bottom ash (slag) stream, and a flue gas stream containing suspended fly ash and vapors of volatile elements or compounds. A further partitioning of the flue gas stream takes place in the particulate emission control devices that efficiently remove larger fly ash particles but are less efficient for vapors and finer particles. Environmental control agencies, researchers, and general public have become increasingly concerned with the mobilization of trace elements to the environment from solid and hazardous waste incinerators. Mercury is the trace element of particular concern since, during combustion, most of the mercury present in the influent stream is transferred into the vapor phase due to its high volatility. There is a considerable evidence in the literature that currently used pollution abatement technologies (flue gas clean-up and particulate control devices) are not capable of controlling gas phase mercury emissions. Activated carbon adsorption is a unit process that offers great promise for achieving high quality air emissions with respect to mercury and other trace elements that might be present in gases emitted from solid and hazardous waste incinerators. This study is designed to evaluate the rate of vapor-phase mercury removal by virgin and sulfur impregnated activated carbons under various process conditions. The specific process conditions that will be evaluated for their effect on the rate and mechanism of mercury uptake include temperature, moisture content, oxygen partial pressure, and presence of other compounds and trace elements in the vapor-phase. Accurate description of the kinetics of mercury removal by activated carbon is an essential component in establishing design procedures that would ensure successful application of this efficient technology for mercury control.

  19. Thief process for the removal of mercury from flue gas

    DOEpatents

    Pennline, Henry W.; Granite, Evan J.; Freeman, Mark C.; Hargis, Richard A.; O'Dowd, William J.

    2003-02-18

    A system and method for removing mercury from the flue gas of a coal-fired power plant is described. Mercury removal is by adsorption onto a thermally activated sorbent produced in-situ at the power plant. To obtain the thermally activated sorbent, a lance (thief) is inserted into a location within the combustion zone of the combustion chamber and extracts a mixture of semi-combusted coal and gas. The semi-combusted coal has adsorptive properties suitable for the removal of elemental and oxidized mercury. The mixture of semi-combusted coal and gas is separated into a stream of gas and semi-combusted coal that has been converted to a stream of thermally activated sorbent. The separated stream of gas is recycled to the combustion chamber. The thermally activated sorbent is injected into the duct work of the power plant at a location downstream from the exit port of the combustion chamber. Mercury within the flue gas contacts and adsorbs onto the thermally activated sorbent. The sorbent-mercury combination is removed from the plant by a particulate collection system.

  20. Apparatus and method for removing mercury vapor from a gas stream

    DOEpatents

    Ganesan, Kumar

    2008-01-01

    A metallic filter effectively removes mercury vapor from gas streams. The filter captures the mercury which then can be released and collected as product. The metallic filter is a copper mesh sponge plated with a six micrometer thickness of gold. The filter removes up to 90% of mercury vapor from a mercury contaminated gas stream.

  1. Mercury and tritium removal from DOE waste oils

    SciTech Connect

    Klasson, E.T.

    1997-10-01

    This work covers the investigation of vacuum extraction as a means to remove tritiated contamination as well as the removal via sorption of dissolved mercury from contaminated oils. The radiation damage in oils from tritium causes production of hydrogen, methane, and low-molecular-weight hydrocarbons. When tritium gas is present in the oil, the tritium atom is incorporated into the formed hydrocarbons. The transformer industry measures gas content/composition of transformer oils as a diagnostic tool for the transformers` condition. The analytical approach (ASTM D3612-90) used for these measurements is vacuum extraction of all gases (H{sub 2}, N{sub 2}, O{sub 2}, CO, CO{sub 2}, etc.) followed by analysis of the evolved gas mixture. This extraction method will be adapted to remove dissolved gases (including tritium) from the SRS vacuum pump oil. It may be necessary to heat (60{degrees}C to 70{degrees}C) the oil during vacuum extraction to remove tritiated water. A method described in the procedures is a stripper column extraction, in which a carrier gas (argon) is used to remove dissolved gases from oil that is dispersed on high surface area beads. This method appears promising for scale-up as a treatment process, and a modified process is also being used as a dewatering technique by SD Myers, Inc. (a transformer consulting company) for transformers in the field by a mobile unit. Although some mercury may be removed during the vacuum extraction, the most common technique for removing mercury from oil is by using sulfur-impregnated activated carbon (SIAC). SIAC is currently being used by the petroleum industry to remove mercury from hydrocarbon mixtures, but the sorbent has not been previously tested on DOE vacuum oil waste. It is anticipated that a final process will be similar to technologies used by the petroleum industry and is comparable to ion exchange operations in large column-type reactors.

  2. Novel sorbents for mercury removal from flue gas

    SciTech Connect

    Granite, E.J.; Pennline, H.W.; Hargis, R.A.

    2000-04-01

    A laboratory-scale packed-bed reactor system is used to screen sorbents for their capability to remove elemental mercury from various carrier gases. When the carrier gas is argon, an on-line atomic fluorescence spectrophotometer (AFS), used in a continuous mode, monitors the elemental mercury concentration in the inlet and outlet streams of the packed-bed reactor. The mercury concentration in the inlet and outlet streams of the packed-bed reactor. The mercury concentration in the reactor inlet gas and the reactor temperature are held constant during a test. For more complex carrier gases, the capacity is determined off-line by analyzing the spent sorbent with either a cold vapor atomic absorption spectrophotometer (CVAAS) or an inductively coupled argon plasma atomic emission spectrophotometer (ICP-AES). The capacities and breakthrough times of several commercially available activated carbons as well as novel sorbents were determined as a function of various parameters. The mechanisms of mercury removal by the sorbents are suggested by combining the results of the packed-bed testing with various analytical results.

  3. An ionic liquid process for mercury removal from natural gas.

    PubMed

    Abai, Mahpuzah; Atkins, Martin P; Hassan, Amiruddin; Holbrey, John D; Kuah, Yongcheun; Nockemann, Peter; Oliferenko, Alexander A; Plechkova, Natalia V; Rafeen, Syamzari; Rahman, Adam A; Ramli, Rafin; Shariff, Shahidah M; Seddon, Kenneth R; Srinivasan, Geetha; Zou, Yiran

    2015-05-14

    Efficient scrubbing of mercury vapour from natural gas streams has been demonstrated both in the laboratory and on an industrial scale, using chlorocuprate(II) ionic liquids impregnated on high surface area porous solid supports, resulting in the effective removal of mercury vapour from natural gas streams. This material has been commercialised for use within the petroleum gas production industry, and has currently been running continuously for three years on a natural gas plant in Malaysia. Here we report on the chemistry underlying this process, and demonstrate the transfer of this technology from gram to ton scale. PMID:25722100

  4. EP-toxicity testing of mercury removal resin grout

    SciTech Connect

    Mersman, K.E.

    1984-07-18

    To determine which category a waste will fit into, the EPA requires a classification test. The test, EP-toxicity, consists of a physical integrity test followed by an extraction. For the case of the mercury removal resin grout, the mercury concentration in the extract cannot exceed 0.2 mg/L if the waste is to be classified as ``solid waste.`` Otherwise, the waste is classified as ``hazardous.`` Simulated process solutions were used to load the mercury removal resin. The resin was solidified with the addition of cement and water using a formulation based on grout formulations typically used to solidify power reactor ion exchange resins. Envirodyne Engineers of St. Louis, Missouri, an EPA sanctioned laboratory, performed the EP-toxicity test for the two samples. One sample was a blank which was made with unloaded resin. For the formulation tested, the EP-toxicity test results showed that the mercury removal resin grout does not fit into the ``hazardous waste`` category.

  5. Utilization of Partially Gasified Coal for Mercury Removal

    SciTech Connect

    Chris Samuelson; Peter Maly; David Moyeda

    2008-09-09

    In this project, General Electric Energy and Environmental Research Corporation (EER) developed a novel mercury (Hg) control technology in which the sorbent for gas-phase Hg removal is produced from coal in a gasification process in-situ at a coal burning plant. The main objective of this project was to obtain technical information necessary for moving the technology from pilot-scale testing to a full-scale demonstration. A pilot-scale gasifier was used to generate sorbents from both bituminous and subbituminous coals. Once the conditions for optimizing sorbent surface area were identified, sorbents with the highest surface area were tested in a pilot-scale combustion tunnel for their effectiveness in removing Hg from coal-based flue gas. It was determined that the highest surface area sorbents generated from the gasifier process ({approx}600 m{sup 2}/g) had about 70%-85% of the reactivity of activated carbon at the same injection rate (lb/ACF), but were effective in removing 70% mercury at injection rates about 50% higher than that of commercially available activated carbon. In addition, mercury removal rates of up to 95% were demonstrated at higher sorbent injection rates. Overall, the results of the pilot-scale tests achieved the program goals, which were to achieve at least 70% Hg removal from baseline emissions levels at 25% or less of the cost of activated carbon injection.

  6. Mercury removal from aqueous streams utilizing microemulsion liquid membranes

    SciTech Connect

    Larson, K.A.; Wiencek, J.M.

    1994-11-01

    The goal of this work is the removal of mercury ion from wastewater using thermodynamically stable microemulsions as liquid membranes. The research focuses on identification and modeling of the appropriate aqueous and organic phase equilibrium reactions for mercury extraction and stripping, comparison of extraction kinetics between coarse emulsions and microemulsions, and demulsification and recovery of the emulsion components. An oleic acid microemulsion liquid membrane (water-in-oil) containing sulfuric acid as the internal phase reduces the feed phase mercury concentration from 460 mg/l to 0.84 mg/l in a single contacting. This compares favorably with a control extraction (oleic acid/no internal phase) which results in a final concentration of 20 mg/l Hg{sup +2}. Microemulsions can be demulsified using butanol as an additive. The demulsification kinetics are proportional to butanol concentration and temperature and inversely proportional to surfactant concentration. The demulsification rate is second order with respect to water concentration which implies that the rate-limiting step in the process is the rate of internal phase droplet encounters. Proof-of-principle experiments demonstrate the ability to extract mercury ion using microemulsions formulated with recycled organic phase, albeit at a somewhat reduced efficiency. The reduced efficiency is attributed to increased internal phase leakage due to residual butanol in the oil phase. Finally, the cycle is brought around full circle by recovering metallic mercury from the internal phase by electroplating. 27 refs., 11 figs., 1 tab.

  7. Novel sorbents for mercury removal from flue gas

    SciTech Connect

    Granite, E.J.; Pennline, H.W.; Hargis, R.A.

    1999-07-01

    A laboratory-scale packed-bed reactor system is used to screen sorbents for their capability to remove elemental mercury from various carrier gases. When the carrier gas is argon, an on-line atomic fluorescence spectrophotometer (AFS), used in a continuous mode, monitors the elemental mercury concentration in the inlet and outlet streams of the packed-bed reactor. The mercury concentration in the reactor inlet gas and the reactor temperature are held constant during a test. For more complex carrier gases, capacity is determined off-line by analyzing the spent sorbent with either a cold vapor atomic absorption spectrophotometer (CVAAS) or an inductively coupled argon plasma atomic emission spectrophotometer (ICP-AES). The capacities and breakthrough times of several commercially available activated carbons, as well as novel sorbents, were determined as a function of various parameters. The mechanisms of mercury removal by the sorbents are suggested by combining the results of the packed-bed testing with various analytical results.

  8. Novel Process for Removal and Recovery of Vapor Phase Mercury

    SciTech Connect

    Greenwell, Collin; Roberts, Daryl L; Albiston, Jason; Stewart, Robin; Broderick, Tom

    1998-03-09

    We demonstrated in the Phase I program all key attributes of a new technology for removing mercury from flue gases, namely, a) removal of greater than 95% of both elemental and oxidized forms of mercury, both in the laboratory and in the field b) regenerability of the sorbent c) ability to scale up, and d) favorable economics. The Phase I program consisted of four tasks other than project reporting: Task I-1 Screen Sorbent Configurations in the Laboratory Task I-2 Design and Fabricate Bench-Scale Equipment Task I-3 Test Bench-Scale Equipment on Pilot Combustor Task I-4 Evaluate Economics Based on Bench-Scale Results In Task I-1, we demonstrated that the sorbents are thermally durable and are regenerable through at least 55 cycles of mercury uptake and desorption. We also demonstrated two low-pressure- drop configurations of the sorbent, namely, a particulate form and a monolithic form. We showed that the particulate form of the sorbent would take up 100% of the mercury so long as the residence time in a bed of the sorbent exceeded 0.1 seconds. In principle, the particulate form of the sorbent could be imbedded in the back side of a higher temperature bag filter in a full-scale application. With typical bag face velocities of four feet per minute, the thickness of the particulate layer would need to be about 2000 microns to accomplish the uptake of the mercury. For heat transfer efficiency, however, we believed the monolithic form of the sorbent would be the more practical in a full scale application. Therefore, we purchased commercially-available metallic monoliths and applied the sorbent to the inside of the flow channels of the monoliths. At face velocities we tested (up to 1.5 ft/sec), these monoliths had less than 0.05 inches of water pressure drop. We tested the monolithic form of the sorbent through 21 cycles of mercury sorption and desorption in the laboratory and included a test of simultaneous uptake of both mercury and mercuric chloride. Overall, in Task

  9. Method for the removal of elemental mercury from a gas stream

    DOEpatents

    Mendelsohn, Marshall H.; Huang, Hann-Sheng

    1999-01-01

    A method is provided to remove elemental mercury from a gas stream by reacting the gas stream with an oxidizing solution to convert the elemental mercury to soluble mercury compounds. Other constituents are also oxidized. The gas stream is then passed through a wet scrubber to remove the mercuric compounds and oxidized constituents.

  10. Method for combined removal of mercury and nitrogen oxides from off-gas streams

    DOEpatents

    Mendelsohn, Marshall H.; Livengood, C. David

    2006-10-10

    A method for removing elemental Hg and nitric oxide simultaneously from a gas stream is provided whereby the gas stream is reacted with gaseous chlorinated compound to convert the elemental mercury to soluble mercury compounds and the nitric oxide to nitrogen dioxide. The method works to remove either mercury or nitrogen oxide in the absence or presence of each other.

  11. A method for the removal of elemental mercury from a gas stream

    SciTech Connect

    Mendelsohn, Marshall H.; Huang, Hann-Sheng

    1997-12-01

    A method is provided to remove elemental mercury from a gas stream by reacting the gas stream with an oxidizing solution to convert the elemental mercury to soluble mercury compounds. Other constituents are also oxidized. The gas stream is then passed through a wet scrubber to remove the mercuric compounds and oxidized constituents.

  12. Method for the removal of elemental mercury from a gas stream

    DOEpatents

    Mendelsohn, M.H.; Huang, H.S.

    1999-05-04

    A method is provided to remove elemental mercury from a gas stream by reacting the gas stream with an oxidizing solution to convert the elemental mercury to soluble mercury compounds. Other constituents are also oxidized. The gas stream is then passed through a wet scrubber to remove the mercuric compounds and oxidized constituents. 7 figs.

  13. Self-Assembled Mercaptan on Mesoporous Silica (SAMMS) technology of mercury removal and stabilization

    SciTech Connect

    Feng, Xiangdong; Liu, Jun; Fryxell, G.E.

    1997-09-01

    This paper explains the technology developed to produce Self-Assembled Mercaptan on Mesoporous Silica (SAMMS) for mercury removal from aqueous wastewater and from organic wastes. The characteristics of SAMMS materials, including physical characteristics and mercury loading, and its application for mercury removal and stabilization are discussed. Binding kinetics and binding speciations are reported. Preliminary cost estimates are provided for producing SAMMS materials and for mercury removal from wastewater. The characteristics of SAMMS in mercury separation were studied at PNNL using simulated aqueous tank wastes and actual tritiated pump oil wastes from Savannah River Site; preliminary results are outlined. 47 refs., 16 figs., 16 tabs.

  14. Removal of mercury (II), elemental mercury and arsenic from simulated flue gas by ammonium sulphide.

    PubMed

    Ning, Ping; Guo, Xiaolong; Wang, Xueqian; Wang, Ping; Ma, Yixing; Lan, Yi

    2015-01-01

    A tubular resistance furnace was used as a reactor to simulate mercury and arsenic in smelter flue gases by heating mercury and arsenic compounds. The flue gas containing Hg(2+), Hg(0) and As was treated with ammonium sulphide. The experiment was conducted to investigate the effects of varying the concentration of ammonium sulphide, the pH value of ammonium sulphide, the temperature of ammonium sulphide, the presence of SO2 and the presence of sulphite ion on removal efficiency. The prepared adsorption products were characterized by Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy and scanning electron microscopy. The results showed that the optimal concentration of ammonium sulphide was 0.8 mol/L. The optimal pH value of ammonium sulphide was 10, and the optimal temperature of ammonium sulphide was 20°C.Under the optimum conditions, the removal efficiency of Hg(2+), Hg(0) and As could reach 99%, 88.8%, 98%, respectively. In addition, SO2 and sulphite ion could reduce the removal efficiency of mercury and arsenic from simulated flue gas. PMID:25965547

  15. Evaluation of mercury speciation and removal through air pollution control devices of a 190 MW boiler.

    PubMed

    Wu, Chengli; Cao, Yan; Dong, Zhongbing; Cheng, Chinmin; Li, Hanxu; Pan, Weiping

    2010-01-01

    Air pollution control devices (APCDs) are installed at coal-fired power plants for air pollutant regulation. Selective catalytic reduction (SCR) and wet flue gas desulfurization (FGD) systems have the co-benefits of air pollutant and mercury removal. Configuration and operational conditions of APCDs and mercury speciation affect mercury removal efficiently at coal-fired utilities. The Ontario Hydro Method (OHM) recommended by the U.S. Environmental Protection Agency (EPA) was used to determine mercury speciation simultaneously at five sampling locations through SCR-ESP-FGD at a 190 MW unit. Chlorine in coal had been suggested as a factor affecting the mercury speciation in flue gas; and low-chlorine coal was purported to produce less oxidized mercury (Hg2+) and more elemental mercury (Hg0) at the SCR inlet compared to higher chlorine coal. SCR could oxidize elemental mercury into oxidized mercury when SCR was in service, and oxidation efficiency reached 71.0%. Therefore, oxidized mercury removal efficiency was enhanced through a wet FGD system. In the non-ozone season, about 89.5%-96.8% of oxidized mercury was controlled, but only 54.9%-68.8% of the total mercury was captured through wet FGD. Oxidized mercury removal efficiency was 95.9%-98.0%, and there was a big difference in the total mercury removal efficiencies from 78.0% to 90.2% in the ozone season. Mercury mass balance was evaluated to validate reliability of OHM testing data, and the ratio of mercury input in the coal to mercury output at the stack was from 0.84 to 1.08. PMID:20397418

  16. Elemental mercury removals observed in a laboratory-scale wet FGD scrubber system

    SciTech Connect

    Mendelsohn, M.H.; Wu, J.; Huang, H.; Livengood, C.D.

    1994-08-01

    Published data are limited regarding gaseous mercury removal in wet scrubber flue-gas desulfurization (FGD) systems. The data that do exist show a wide variation in reported mercury removals, from about 5 to 95%. We have performed tests for the removal of gaseous elemental mercury in a well-controlled laboratory environment by using both conventional and modified configurations of an aqueous scrubber system. Results from these tests strongly suggest that the removal of elemental mercury in a wet scrubber system is controlled by liquid-film resistance. Our results have also led us to hypothesize that the mercury-containing species in a flue-gas stream consist of only two types: elemental mercury and oxidized mercury compounds. We further assert that the differences observed in mercury removal reflect different proportions of each of these two types of mercury-containing species. We suggest that the total mercury removal will be high when the actual, but unmeasured, proportion of oxidized mercury compounds is high.

  17. Feasibility of mercury removal from simulated flue gas by activated chars made from poultry manures

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Increased emphasis on reduction of mercury emissions from coal fired electric power plants has resulted in environmental regulations that may in the future require application of activated carbons as mercury sorbents for mercury removal. At the same time, the quantity of poultry manure generated eac...

  18. The secondary release of mercury in coal fly ash-based flue-gas mercury removal technology.

    PubMed

    He, Jingfeng; Duan, Chenlong; Lei, Mingzhe; Zhu, Xuemei

    2016-01-01

    The secondary release of mercury from coal fly ash is a negative by-product from coal-fired power plants, and requires effective control to reduce environmental pollution. Analysing particle size distribution and composition of the coal fly ash produced by different mercury removing technologies indicates that the particles are generally less than 0.5 mm in size and are composed mainly of SiO2, Al2O3, and Fe2O3. The relationships between mercury concentration in the coal fly ash, its particle size, and loss of ignition were studied using different mercury removing approaches. The research indicates that the coal fly ash's mercury levels are significantly higher after injecting activated carbon or brominating activated carbon when compared to regular cooperating-pollution control technology. This is particularly true for particle size ranges of >0.125, 0.075-0.125, and 0.05-0.075 mm. Leaching experiments revealed the secondary release of mercury in discarded coal fly ash. The concentration of mercury in the coal fly ash increases as the quantity of injecting activated carbon or brominating activated carbon increases. The leached concentrations of mercury increase as the particle size of the coal fly ash increases. Therefore, the secondary release of mercury can be controlled by adding suitable activated carbon or brominating activated carbon when disposing of coal fly ash. Adding CaBr2 before coal combustion in the boiler also helps control the secondary release of mercury, by increasing the Hg(2+) concentration in the leachate. This work provides a theoretical foundation for controlling and removing mercury in coal fly ash disposal. PMID:26121324

  19. Mercury removal in wastewater by iron oxide nanoparticles

    NASA Astrophysics Data System (ADS)

    Vélez, E.; Campillo, G. E.; Morales, G.; Hincapié, C.; Osorio, J.; Arnache, O.; Uribe, J. I.; Jaramillo, F.

    2016-02-01

    Mercury is one of the persistent pollutants in wastewater; it is becoming a severe environmental and public health problem, this is why nowadays its removal is an obligation. Iron oxide nanoparticles are receiving much attention due to their properties, such as: great biocompatibility, ease of separation, high relation of surface-area to volume, surface modifiability, reusability, excellent magnetic properties and relative low cost. In this experiment, Fe3O4 and γ-Fe2O3 nanoparticles were synthesized using iron salts and NaOH as precipitation agents, and Aloe Vera as stabilizing agent; then these nanoparticles were characterized by three different measurements: first, using a Zetasizer Nano ZS for their size estimation, secondly UV-visible spectroscopy which showed the existence of resonance of plasmon at λmax∼360 nm, and lastly by Scanning Electron Microscopy (SEM) to determine nanoparticles form. The results of this characterization showed that the obtained Iron oxides nanoparticles have a narrow size distribution (∼100nm). Mercury removal of 70% approximately was confirmed by atomic absorption spectroscopy measurements.

  20. A NOVEL METHOD FOR THE REMOVAL OF TRACE CONCENTRATION OF ELEMENTAL MERCURY FROM UTILITY EMISSIONS

    SciTech Connect

    Joseph L. Katz

    2002-09-17

    A new technique for removal of elemental mercury from emissions of coal-fired utilities was investigated. The key idea is to selectively photo ionize the mercury atoms. A strong electric field gradient then drags them to the negative plate where they can be collected and removed.

  1. Experimental dosing of wetlands with coagulants removes mercury from surface water and decreases mercury bioaccumulation in fish.

    PubMed

    Ackerman, Joshua T; Kraus, Tamara E C; Fleck, Jacob A; Krabbenhoft, David P; Horwath, William R; Bachand, Sandra M; Herzog, Mark P; Hartman, C Alex; Bachand, Philip A M

    2015-05-19

    Mercury pollution is widespread globally, and strategies for managing mercury contamination in aquatic environments are necessary. We tested whether coagulation with metal-based salts could remove mercury from wetland surface waters and decrease mercury bioaccumulation in fish. In a complete randomized block design, we constructed nine experimental wetlands in California's Sacramento-San Joaquin Delta, stocked them with mosquitofish (Gambusia affinis), and then continuously applied agricultural drainage water that was either untreated (control), or treated with polyaluminum chloride or ferric sulfate coagulants. Total mercury and methylmercury concentrations in surface waters were decreased by 62% and 63% in polyaluminum chloride treated wetlands and 50% and 76% in ferric sulfate treated wetlands compared to control wetlands. Specifically, following coagulation, mercury was transferred from the filtered fraction of water into the particulate fraction of water which then settled within the wetland. Mosquitofish mercury concentrations were decreased by 35% in ferric sulfate treated wetlands compared to control wetlands. There was no reduction in mosquitofish mercury concentrations within the polyaluminum chloride treated wetlands, which may have been caused by production of bioavailable methylmercury within those wetlands. Coagulation may be an effective management strategy for reducing mercury contamination within wetlands, but further studies should explore potential effects on wetland ecosystems. PMID:25893963

  2. Experimental dosing of wetlands with coagulants removes mercury from surface water and decreases mercury bioaccumulation in fish

    USGS Publications Warehouse

    Ackerman, Joshua T.; Kraus, Tamara E.C.; Fleck, Jacob A.; Krabbenhoft, David P.; Horwarth, William R.; Bachand, Sandra M.; Herzog, Mark; Hartman, Christopher; Bachand, Philip A.M.

    2015-01-01

    Mercury pollution is widespread globally, and strategies for managing mercury contamination in aquatic environments are necessary. We tested whether coagulation with metal-based salts could remove mercury from wetland surface waters and decrease mercury bioaccumulation in fish. In a complete randomized block design, we constructed nine experimental wetlands in California's Sacramento-San Joaquin Delta, stocked them with mosquitofish (Gambusia affinis), and then continuously applied agricultural drainage water that was either untreated (control), or treated with polyaluminum chloride or ferric sulfate coagulants. Total mercury and methylmercury concentrations in surface waters were decreased by 62% and 63% in polyaluminum chloride treated wetlands and 50% and 76% in ferric sulfate treated wetlands compared to control wetlands. Specifically, following coagulation, mercury was transferred from the filtered fraction of water into the particulate fraction of water which then settled within the wetland. Mosquitofish mercury concentrations were decreased by 35% in ferric sulfate treated wetlands compared to control wetlands. There was no reduction in mosquitofish mercury concentrations within the polyaluminum chloride treated wetlands, which may have been caused by production of bioavailable methylmercury within those wetlands. Coagulation may be an effective management strategy for reducing mercury contamination within wetlands, but further studies should explore potential effects on wetland ecosystems.

  3. Mercury removal from waste gases by manganese oxide acceptors

    SciTech Connect

    Cavallaro, S.; Bertuccio, N.; Antonucci, P.; Giordano, N.

    1982-02-01

    Removal of mercury vapor from a waste gas has been investigated at atmospheric pressure and at ambient temperature using a series of manganese-based reagents supported on an inert medium. The effect of catalyst composition on activity and the influence of relative humidity of the air stream have been studied. Whereas ..gamma..-Al/sub 2/O/sub 3/ has a very low mercury sorption capacity, sorption occurs copiously on impregnated silver- and copper-doped MnO/sub 2/ acceptors but the much higher activity is reduced by the presence of water vapour in the carrier gas. The morphological and microstructural characterization of the (MnO/sub 2/, AgNO/sub 3/) ..gamma..-Al/sub 2/O/sub 3/ reagents has shown selective deposition of AgNO/sub 3/ particles on ..beta..-MnO/sub 2/ crystallites which are dispersed on the ..gamma..-Al/sub 2/O/sub 3/ matrix. As the adsorption is associated with a sequence of specific colour changes a chemical oxidation mechanism is proposed. Acceptor deactivation is discussed. 9 figures, 3 tables.

  4. Removal and speciation of mercury compounds in flue gas from a waste incinerator.

    PubMed

    Hwang, In-Hee; Minoya, Hiroshi; Matsuo, Takayuki; Matsuto, Toshihiko; Tojo, Yasumasa

    2016-11-01

    The management and control of mercury emissions from waste incinerators have become more significant, because waste incinerators are sinks to treat mercury-containing consumer products. This study investigated the effects of mercury concentrations and waste incineration temperatures on mercury speciation using a lab-scale experimental instrument. The removal characteristics of different mercury species were also investigated using an apparatus to simulate the fabric filter with a thin layer of additives such as Ca(OH)2 and NaHCO3, activated carbon (AC), and fly ash. HgCl2 generation rates peaked at 800°C for initial Hg(0) concentrations of 0.08-3.61 mg/Nm(3) in the presence of 400 ppm HCl. A linear relationship was established between the generation rate of HgCl2 and the logarithmic value of initial mercury concentration. Fly ash proved highly efficient in mercury removal, being equal or superior to AC. On the other hand, Ca(OH)2 and NaHCO3 were shown to have no effects on mercury removal. In the dry-scrubbing process, alkali agent is often sprayed in amounts beyond those stoichiometrically required to aid acidic gas removal. The research suggests, however, that this may hinder mercury removal from the flue gas of solid waste incinerators. PMID:27031438

  5. Removal of mercury contamination on primary mass standards by hydrogen plasma and thermal desorption

    NASA Astrophysics Data System (ADS)

    Fuchs, P.; Marti, K.; Russi, S.

    2013-02-01

    The removal of a high mercury contamination on a Pt reference mass by thermal desorption was studied directly by x-ray photoemission spectroscopy (XPS). Subsequently the contamination mechanism was investigated. Samples of PtIr and AuPt exposed to vapour of mercury in air were studied using XPS and gravimetric mass determination. We find an extremely rapid mercury contamination which takes place within minutes and reaches an initial equilibrium state after 2 h to 4 h. Roughly 1 to 2 monolayers of mercury adsorbs directly on the metal surface. A natural contamination of carbon and oxygen compounds is at the top. Due to the accumulation of mercury, we find a gain in mass which corresponds to 20 µg to 26 µg for a PtIr standard. XPS data from a historical Pt standard give strong evidence for further average mercury accumulation of (1.3 ± 0.1) µg/year during a period of more than a century. This can be explained by a two-step mechanism presented in this study. The speed of contamination depends on the initial surface conditions. Polishing activates the surface and results in an enhanced accumulation of mercury. Natural contamination by C and O can delay but not prevent contamination. We further demonstrate that the mercury contamination can be removed by both hydrogen plasma and thermal desorption. The removal of mercury by hydrogen plasma can directly be attributed to the synthesis of gaseous mercury dihydrides at low pressures.

  6. Mercury removal from solution by superconducting magnetic separation with nanostructured magnetic adsorbents

    NASA Astrophysics Data System (ADS)

    Okamoto, T.; Tachibana, S.; Miura, O.; Takeuchi, M.

    2011-11-01

    Recently, mercury Hg concentration in human blood increases due to expanding the global mercury contamination. Excess mercury bioaccumulation poses a significant health risk. In order to decrease mercury concentration in the environment and human blood, we have developed two different kinds of nanostructured magnetic adsorbents for mercury to apply them to superconducting magnetic separation instead of conventional filtration. One is magnetic beads (MBs) which have nanosize magnetite particles in the core and a lot of SH radicals on the surface to adsorb Hg ions effectively. MBs were developed mainly to remove mercury from human blood. The maximum amount of the adsorption for MBs is 6.3 mg/g in the solution in less than a minute. Dithiothreitol can easily remove mercury adsorbed to MBs, hence MBs can be reusable. The other is nanostructured magnetic activated carbon (MAC) which is activated carbon with mesopores and nanosize magnetite. The maximum amount of the adsorption for MAC is 38.3 mg/g in the solution. By heat-treatment mercury can be easily removed from MAC. We have studied superconducting magnetic separation using each adsorbent for mercury removal from solution.

  7. Bioaccumulation and elimination of mercury in juvenile seabass (Dicentrarchus labrax) in a warmer environment.

    PubMed

    Maulvault, Ana Luísa; Custódio, Ana; Anacleto, Patrícia; Repolho, Tiago; Pousão, Pedro; Nunes, Maria Leonor; Diniz, Mário; Rosa, Rui; Marques, António

    2016-08-01

    Warming is an expected impact of climate change that will affect coastal areas in the future. These areas are also subjected to strong anthropogenic pressures leading to chemical contamination. Yet, the consequences of both factors for marine ecosystems, biota and consumers are still unknown. The present work aims to investigate, for the first time, the effect of temperature increase on bioaccumulation and elimination of mercury [(total mercury (THg) and methylmercury (MeHg)] in three tissues (muscle, liver, and brain) of a commercially important seafood species - European seabass (Dicentrarchus labrax). Fish were exposed to the ambient temperature currently used in seabass rearing (18°C) and to the expected ocean warming (+4°C, i.e. 22°C), as well as dietary MeHg during 28 days, followed by a depuration period of 28 days fed with a control diet. In both temperature exposures, higher MeHg contents were observed in the brain, followed by the muscle and liver. Liver registered the highest elimination percentages (EF; up to 64% in the liver, 20% in the brain, and 3% in the muscle). Overall, the results clearly indicate that a warming environment promotes MeHg bioaccumulation in all tissues (e.g. highest levels in brain: 8.1mgkg(-1) ww at 22°C against 6.2mgkg(-1) ww at 18°C after 28 days of MeHg exposure) and hampers MeHg elimination (e.g. liver EF decreases after 28 days of depuration: from 64.2% at 18°C to 50.3% at 22°C). These findings suggest that seafood safety may be compromised in a warming context, particularly for seafood species with contaminant concentrations close to the current regulatory levels. Hence, results point out the need to strengthen research in this area and to revise and/or adapt the current recommendations regarding human exposure to chemical contaminants through seafood consumption, in order to integrate the expected effects of climate change. PMID:27179934

  8. Treatability study for removal of leachable mercury in crushed fluorescent lamps

    SciTech Connect

    Bostick, W.D.; Beck, D.E.; Bowser, K.T.

    1996-02-01

    Nonserviceable fluorescent lamps removed from radiological control areas at the Oak Ridge Department of Energy facilities have been crushed and are currently managed as mixed waste (hazardous and radiologically contaminated). We present proposed treatment flowsheets and supporting treatability study data for conditioning this solid waste residue so that it can qualify for disposal in a sanitary landfill. Mercury in spent fluorescent lamps occurs primarily as condensate on high-surface-area phosphor material. It can be solubilized with excess oxidants (e.g., hypochlorite solution) and stabilized by complexation with halide ions. Soluble mercury in dechlorinated saline solution is effectively removed by cementation with zero-valent iron in the form of steel wool. In packed column dynamic flow testing, soluble mercury was reduced to mercury metal and insoluble calomel, loading > 1.2 g of mercury per grain of steel wool before an appreciable breakthrough of soluble mercury in the effluent.

  9. [Removal Characteristics of Elemental Mercury by Mn-Ce/molecular Sieve].

    PubMed

    Tan, Zeng-qiang; Niu, Guo-ping; Chen, Xiao-wen; An, Zhen

    2015-06-01

    The impregnation method was used to support molecular sieve with active manganese and cerium components to obtain a composite molecular sieve catalyst. The mercury removal performance of the catalyst was studied with a bench-scale setup. XPS analysis was used to characterize the sample before and after the modification in order to study the changes in the active components of the catalyst prepared. The results showed that the catalyst carrying manganese and cerium components had higher oxidation ability of elemental mercury in the temperature range of 300 degrees C - 450 degrees C, especially at 450 degrees C, the oxidation efficiency of elemental mercury was kept above 80%. The catalyst had more functional groups that were conducive to the oxidation of elemental mercury, and the mercury removal mainly depended on the chemical adsorption. The SO2 and NO in flue gas could inhibit the oxidation of elemental mercury to certain extent. PMID:26387298

  10. Mercury Reduction and Removal from High Level Waste at the Defense Waste Processing Facility - 12511

    SciTech Connect

    Behrouzi, Aria; Zamecnik, Jack

    2012-07-01

    The Defense Waste Processing Facility processes legacy nuclear waste generated at the Savannah River Site during production of enriched uranium and plutonium required by the Cold War. The nuclear waste is first treated via a complex sequence of controlled chemical reactions and then vitrified into a borosilicate glass form and poured into stainless steel canisters. Converting the nuclear waste into borosilicate glass is a safe, effective way to reduce the volume of the waste and stabilize the radionuclides. One of the constituents in the nuclear waste is mercury, which is present because it served as a catalyst in the dissolution of uranium-aluminum alloy fuel rods. At high temperatures mercury is corrosive to off-gas equipment, this poses a major challenge to the overall vitrification process in separating mercury from the waste stream prior to feeding the high temperature melter. Mercury is currently removed during the chemical process via formic acid reduction followed by steam stripping, which allows elemental mercury to be evaporated with the water vapor generated during boiling. The vapors are then condensed and sent to a hold tank where mercury coalesces and is recovered in the tank's sump via gravity settling. Next, mercury is transferred from the tank sump to a purification cell where it is washed with water and nitric acid and removed from the facility. Throughout the chemical processing cell, compounds of mercury exist in the sludge, condensate, and off-gas; all of which present unique challenges. Mercury removal from sludge waste being fed to the DWPF melter is required to avoid exhausting it to the environment or any negative impacts to the Melter Off-Gas system. The mercury concentration must be reduced to a level of 0.8 wt% or less before being introduced to the melter. Even though this is being successfully accomplished, the material balances accounting for incoming and collected mercury are not equal. In addition, mercury has not been effectively

  11. Removal of Elemental Mercury from a Gas Stream Facilitated by a Non-Thermal Plasma Device

    SciTech Connect

    Charles Mones

    2006-12-01

    Mercury generated from anthropogenic sources presents a difficult environmental problem. In comparison to other toxic metals, mercury has a low vaporization temperature. Mercury and mercury compounds are highly toxic, and organic forms such as methyl mercury can be bio-accumulated. Exposure pathways include inhalation and transport to surface waters. Mercury poisoning can result in both acute and chronic effects. Most commonly, chronic exposure to mercury vapor affects the central nervous system and brain, resulting in neurological damage. The CRE technology employs a series of non-thermal, plasma-jet devices to provide a method for elemental mercury removal from a gas phase by targeting relevant chemical reactions. The technology couples the known chemistry of converting elemental mercury to ionic compounds by mercury-chlorine-oxygen reactions with the generation of highly reactive species in a non-thermal, atmospheric, plasma device. The generation of highly reactive metastable species in a non-thermal plasma device is well known. The introduction of plasma using a jet-injection device provides a means to contact highly reactive species with elemental mercury in a manner to overcome the kinetic and mass-transfer limitations encountered by previous researchers. To demonstrate this technology, WRI has constructed a plasma test facility that includes plasma reactors capable of using up to four plasma jets, flow control instrumentation, an integrated control panel to operate the facility, a mercury generation system that employs a temperature controlled oven and permeation tube, combustible and mercury gas analyzers, and a ductless fume hood designed to capture fugitive mercury emissions. Continental Research and Engineering (CR&E) and Western Research Institute (WRI) successfully demonstrated that non-thermal plasma containing oxygen and chlorine-oxygen reagents could completely convert elemental mercury to an ionic form. These results demonstrate potential the

  12. Water hyacinths and alligator weeds for removal of lead and mercury from polluted waters

    NASA Technical Reports Server (NTRS)

    Wolverton, B. C.; Mcdonald, R. C.

    1975-01-01

    Removal of lead and mercury by water hyacinths (Eichhornia crassipes) (Mart.) Solms and alligator weeds (Alternanthera philoxeroides) (Mart.) Griesb. was investigated. Water hyacinths demonstrated the ability to remove 0.176 mg of lead and 0.150 mg of mercury per gram of dry plant material from distilled water and river water in a 24-hour period. One acre of water hyacinths is potentially capable of removing 105.6 grams of lead and 90.0 grams of mercury per day. Alligator weeds removed 0.101 mg of lead per gram of dry plant material in a 24-hour period. This same plant also demonstrated the ability to remove a minimum of 0.153 mg of mercury per gram of dry plant material in a six hour period.

  13. Recovery and removal of mercury from mixed wastes. Final report, September 1994--June 1995

    SciTech Connect

    Sutton, W.F.; Weyand, T.E.; Koshinski, C.J.

    1995-06-01

    In recognition of the major environmental problem created by mercury contamination of wastes and soils at an estimated 200,000 sites along US natural gas and oil pipelines and at a number of government facilities, including Oak Ridge, Savannah River, Hanford, and Rocky Flats, the US Department of Energy (DOE) is seeking an effective and economical process for removing mercury from various DOE waste streams in order to allow the base waste streams to be treated by means of conventional technologies. In response to the need for Unproved mercury decontamination technology, Mercury Recovery Services (MRS) has developed and commercialized a thermal treatment process for the recovery of mercury from contaminated soils and industrial wastes. The objectives of this program were to: demonstrate the technical and economic feasibility of the MRS process to successfully remove and recover mercury from low-level mixed waste containing mercury compounds (HgO, HgS, HgCl{sub 2}) and selected heavy metal compounds (PbO, CdO); determine optimum processing conditions required to consistently reduce the residual total mercury content to 1 mg/kg while rendering the treated product nontoxic as determined by TCLP methods; and provide an accurate estimate of the capital and operating costs for a commercial processing facility designed specifically to remove and recovery mercury from various waste streams of interest at DOE facilities. These objectives were achieved in a four-stage demonstration program described within with results.

  14. Removal of mercury from coal-combustion flue gas using regenerable sorbents

    SciTech Connect

    Turchi, C.S.; Albiston, J.; Broderick, T.E.; Stewart, R.M.

    1999-07-01

    The US EPA estimates that coal-fired power plants constitute the largest anthropogenic source of mercury emissions in the US. The Agency has contemplated emission regulations for power plants, but the large gas-flow rates and low mercury concentrations involved have made current treatment options prohibitively expensive. ADA Technologies, Inc. (Englewood, Colorado), in conjunction with the US DOE, is developing regenerable sorbents for the removal and recovery of mercury from flue gas. These sorbents are based on the ability of noble metals to amalgamate mercury at typical flue-gas temperatures and release mercury at higher temperatures. The process allows for recovery of mercury with minimal volumes of secondary wastes and no impact on fly ash quality. In 1997 and 1998, ADA tested a 20-cfm sorbent unit at CONSOL Inc.'s coal-combustion test facility in Library, PA. Results from the 1997 tests indicated that the sorbent can remove elemental and oxidized mercury and can be regenerated without loss of capacity. Design changes were implemented in 1998 to enhance the thermal efficiency of the process and to recover the mercury in a stable form. Testing during autumn, 1998 demonstrated 60% to 90% removal efficiency of mercury from a variety of different coals. However, contradictory removal results were obtained at the end of the test period. Subsequent laboratory analyses indicated that the sorbent had lost over half its capacity for mercury due to a decrease in available sites for mercury sorption. The presence of sulfur compounds on the sorbent suggests that thermal cycling may have condensed acid gases on the sorbent leading to deterioration of the active sorption sites. The regeneration time/temperature profile has been altered to minimize this potential in the upcoming power plant tests.

  15. Removal of mercury from coal-combustion flue gas

    SciTech Connect

    Livengood, C.D.; Huang, H.S.; Mendelsohn, M.H.; Wu, J.M.

    1995-12-31

    Combustion sources, including those using coal for fuel, contribute a significant fraction of total anthropogenic mercury emissions. Recent field studies have shown that current flue-gas cleanup (FGC) systems are relatively ineffective in controlling elemental mercury, which is a major component of the mercury emissions for many systems. Research at Argonne National Laboratory has been focused on techniques to enhance the capture of elemental mercury in existing FGC systems. For dry processes, these studies have included evaluation of activated carbons and investigation of sorbents based upon chemical pretreatment of low-cost mineral substrates. To enhance the ability of wet scrubbers to capture mercury, the studies have looked at the effects of improved mass transfer through both mechanical and chemical means, as well as the conversion of elemental mercury into more soluble species that can be easily absorbed.

  16. Removal of mercury from coal-combustion flue-gas

    SciTech Connect

    Livengood, C.D.; Huang, H.S.; Mendelsohn, M.H.; Wu, J.M.

    1995-12-01

    Combustion sources, including those using coal for fuel, contribute a significant fraction of total anthropogenic mercury emissions. Recent field studies have shown that current flue-gas cleanup (FGC) systems are relatively ineffective in controlling elemental mercury, which is a major component of the mercury emissions for many systems. Research at Argonne National Laboratory has been focused on techniques to enhance the capture of elemental mercury in existing FGC systems. For dry processes, these studies have included evaluation of activated carbons and investigation of sorbents based upon chemical pretreatment of low-cost mineral substrates. To enhance the ability of wet scrubbers to capture mercury, the studies have looked at the effects of improved mass transfer through both mechanical and chemical means, as well as the conversion of elemental mercury into more soluble species that can be easily absorbed.

  17. Enhanced mercury removal from fix-bed reactor by lamella manganese oxide sorbents

    NASA Astrophysics Data System (ADS)

    Cheng, H. W.; Yu, C. T.

    2015-12-01

    Mercury (Hg) is an extremely hazardous metal and attracted more concern because of its high toxicity and bioaccumulation. Several manganese-oxide-containing sorbents prepared by co-precipitation method could exhibit the mercury removal activities toward Hg0. The mercury removal test at the temperature of 300°C has the highest removal efficiency. Under this temperature, the maximum absorption equivalent of Mg-Al-Mn and Mn-Al were up to 90.9 and 247 μg/g, then gradually decreased at 400°C. The mercury removal efficiency declined in the following sequence: Mn-Al > Mg-Al-Mn > Mg-Al-Mn/ACA = Mn/AC(p)> Mn/AC(g), due to the manganese-oxide content formed on the sorbents.

  18. Mercury removal from coal combustion flue gas by modified fly ash.

    PubMed

    Xu, Wenqing; Wang, Hairui; Zhu, Tingyu; Kuang, Junyan; Jing, Pengfei

    2013-02-01

    Fly ash is a potential alternative to activated carbon for mercury adsorption. The effects of physicochemical properties on the mercury adsorption performance of three fly ash samples were investigated. X-ray fluorescence spectroscopy, X-ray photoelectron spectroscopy, and other methods were used to characterize the samples. Results indicate that mercury adsorption on fly ash is primarily physisorption and chemisorption. High specific surface areas and small pore diameters are beneficial to efficient mercury removal. Incompletely burned carbon is also an important factor for the improvement of mercury removal efficiency, in particular. The C-M bond, which is formed by the reaction of C and Ti, Si and other elements, may improve mercury oxidation. The samples modified with CuBr2, CuCl2 and FeCl3 showed excellent performance for Hg removal, because the chlorine in metal chlorides acts as an oxidant that promotes the conversion of elemental mercury (Hg0) into its oxidized form (Hg2+). Cu2+ and Fe3+ can also promote Hg0 oxidation as catalysts. HCl and O2 promote the adsorption of Hg by modified fly ash, whereas SO2 inhibits the Hg adsorption because of competitive adsorption for active sites. Fly ash samples modified with CuBr2, CuCl2 and FeCl3 are therefore promising materials for controlling mercury emissions. PMID:23596961

  19. Graphene-Diatom Silica Aerogels for Efficient Removal of Mercury Ions from Water.

    PubMed

    Kabiri, Shervin; Tran, Diana N H; Azari, Sara; Losic, Dusan

    2015-06-10

    A simple synthetic approach for the preparation of graphene-diatom silica composites in the form of self-assembled aerogels with three-dimensional networks from natural graphite and diatomite rocks is demonstrated for the first time. Their adsorption performance for the removal of mercury from water was studied as a function of contact time, solution pH, and mercury concentration to optimize the reaction conditions. The adsorption isotherm of mercury fitted well with the Langmuir model, representing a very high adsorption capacity of >500 mg of mercury/g of adsorbent. The prepared aerogels exhibited outstanding adsorption performance for the removal of mercury from water, which is significant for environmental applications. PMID:25835089

  20. Development Of Chemical Reduction And Air Stripping Processes To Remove Mercury From Wastewater

    SciTech Connect

    Jackson, Dennis G.; Looney, Brian B.; Craig, Robert R.; Thompson, Martha C.; Kmetz, Thomas F.

    2013-07-10

    This study evaluates the removal of mercury from wastewater using chemical reduction and air stripping using a full-scale treatment system at the Savannah River Site. The existing water treatment system utilizes air stripping as the unit operation to remove organic compounds from groundwater that also contains mercury (C ~ 250 ng/L). The baseline air stripping process was ineffective in removing mercury and the water exceeded a proposed limit of 51 ng/L. To test an enhancement to the existing treatment modality a continuous dose of reducing agent was injected for 6-hours at the inlet of the air stripper. This action resulted in the chemical reduction of mercury to Hg(0), a species that is removable with the existing unit operation. During the injection period a 94% decrease in concentration was observed and the effluent satisfied proposed limits. The process was optimized over a 2-day period by sequentially evaluating dose rates ranging from 0.64X to 297X stoichiometry. A minimum dose of 16X stoichiometry was necessary to initiate the reduction reaction that facilitated the mercury removal. Competing electron acceptors likely inhibited the reaction at the lower 1 doses, which prevented removal by air stripping. These results indicate that chemical reduction coupled with air stripping can effectively treat large-volumes of water to emerging part per trillion regulatory standards for mercury.

  1. Proposed experiment for SnCl{sub 2} treatment of Outfall 200 for the purpose of mercury removal from East Fork Poplar Creek, Y-12 Plant, Oak Ridge, Tennessee

    SciTech Connect

    Southworth, G.R.

    1997-03-01

    Identification and treatment/elimination of point sources of mercury (Hg) to East Fork Poplar Creek (EFPC) within the Y-12 Plant have reduced base flow mercury concentrations considerably; but, after all such actions are completed, nonpoint sources will continue to add mercury to the creek. Studies conducted in 1996 on the use of air stripping to remove elemental mercury from Outfall 51, a mercury-contaminated natural spring, demonstrated that the addition of trace concentrations of stannous chloride (SnCl{sub 2}) converted a large fraction of the dissolved mercury in the outfall to elemental mercury, which could subsequently be removed by air stripping. Dissolved mercury is the dominant form in EFPC at the north/south (N/S) pipes, where it emerges from the underground storm drain network. More than 50% of that mercury is capable of being rapidly reduced by the addition of a 3--5 fold molar excess of stannous chloride. Upon conversion to the volatile gaseous (elemental) form, mercury would be lost across the air-water interface through natural volatilization. EFPC within the Y-12 Plant is shallow, turbulent, and open to sunlight and wind, providing conditions that facilitate natural evasion of volatile chemicals from the water. Preliminary calculations estimate that 75% or more of the elemental mercury could be removed via evasion between the N/S pipes and the Y-l2 Plant boundary (Station 17). Alternatively, elemental mercury might be removed from EFPC in a short reach of stream below the N/S pipes by an in-situ air stripping system which bubbles air through the water column. The purpose of these proposed experiments is to test whether natural volatilization or in-situ air stripping may be used to further reduce baseflow concentrations of mercury in EFPC. Results of this experiment will be useful for understanding the transport and fate of other volatile chemicals in the upper reaches of EFPC.

  2. MICROBIAL REDUCTION OF IONIC MERCURY FOR THE REMOVAL OF MERCURY FROM CONTAMINATED ENVIRONMENTS

    EPA Science Inventory

    A mercury-contaminated freshwater pond, Reality Lake (RL), was investigated in the vicinity of Oak Ridge, Tennessee. he original source of contamination was a nuclear weapons plant where elemental mercury was used from the 1950s to 1970s to enrich lithium isotopes for the product...

  3. Biochar from malt spent rootlets for the removal of mercury from aqueous solutions

    NASA Astrophysics Data System (ADS)

    Boutsika, Lamprini; Manariotis, Ioannis; Karapanagioti, Hrissi K.

    2013-04-01

    Biochar is receiving increased attention as a promising material in environmental applications. It is obtained from the incomplete combustion of carbon-rich biomass under oxygen-limited conditions. One of the many proposed applications of biochars is the removal of metals (e.g., lead, mercury, etc.) from aqueous solutions. Mercury is one of the heavy metals of particular concern due to its toxicity even at relatively low concentration and thus, its removal from aqueous systems is desirable. Malt spent rootlets is a by-product formed during beer production, it is inexpensive and it is produced in high quantities. The objective of the present study was to evaluate the potential use of biochar, produced from malt spent rootlets, to remove mercury from aqueous solutions. Batch experiments were conducted at room temperature (25oC) to obtain the optimum sorption conditions under different pH values, biomass dose, contact time, and solution ionic strength. Sorption kinetics and equilibrium capacity constants were determined at the optimum pH value. Furthermore, the effect of different leaching solutions on mercury desorption from the biochar was examined. All studies with mercury and biochar were conducted at pH 5 that was determined to be the optimum pH for sorption. The proportion of mercury removal increased with the increased dose of the biochar, i.e. from 71% removal for biochar dose of 0.3 g/L, it reached almost 100% removal for biochar dose ˜1 g/L. Based on the isotherm data, the maximum biochar sorption capacity (qmax) for mercury was 99 mg/g. Based on the sorption kinetic data, (qmax) was achieved after 2 h; it should be mentioned that 30% of the (qmax) was observed within the first 5 min. Five leaching solutions were tested for mercury desorption (H2O, HCl, EDTA, NaCl and HNO3). HCl resulted in the highest extraction percentage of the sorbed mercury. The desorbing mercury percentages at 24 h for HCl concentrations 0.1, 0.2, 0.4, 0.8, and 2 M were 62, 59, 62, 69

  4. Removal of mercury from powder river basin coal by low-temperature thermal treatment

    SciTech Connect

    Merriam, N.W.

    1993-07-01

    This report describes work conducted at Western Research Institute (WRI) to remove mercury from Powder River Basin (PRB) coal as part of the research performed under Task 2.1, Development and Optimization of a Process for the Production of a Premium Solid Fuel from Western US Coals, of the 1993 Annual Project Plan. In the tests minus 16 mesh PRB coal was fed to a bench-scale fluidized-bed reactor where it was heated by contact with carbon dioxide fluidizing gas. A side stream of the gas from the reactor was passed through traps containing activated carbon where mercury driven from the coal was collected. The feed coal (which contains about 0.062 milligrams of mercury/kilogram of coal), the fines elutriated from the reactor, the activated carbon, and the condensed water from the reactor were analyzed for mercury. The solid products were analyzed using cold vapor atomic adsorption spectroscopy (ASTM D3684) while the water was analyzed using US Environmental Protection Agency (EPA) Method 245.1 which is based upon reduction of mercury to elemental form followed by adsorption at a wave length of 253.7 nanometers. The results of these tests show that about 70 to 80 wt % of the mercury is removed from the coal when the temperature is raised from about 300{degree}F (149{degree}C) to about 550{degree}F (288{degree}C). The remaining 20 wt % of the mercury remains in the char at temperatures up to about 1100{degree}F (593{degree}C). About 0.5 wt % of the mercury in the feed coal is condensed with water recovered from the coal. Nearly all of the mercury driven from the coal remains in the gas stream. Fines elutriated from the reactor contain about the same concentration of mercury as the feed coal.

  5. Subtask 1.23 - Mercury Removal from Barite the Oil Industry

    SciTech Connect

    Michael Holmes; Carolyn Nyberg; Katie Brandt; Kurt Eylands; Nathan Fiala; Grant Dunham

    2008-09-01

    Drilling muds are used by the oil and gas industry to provide a seal and to float rock chips to the surface during the drilling process. Barite (naturally occurring barium sulfate ore) is commonly used as a weighting agent additive in drilling muds because it is chemically nonreactive and has a high specific gravity (between 4.2 and 4.25 at 20 C). Because of environmental concerns, barite used by the oil and gas industry in the Gulf of Mexico must be certified to contain less than 1 mg/kg of mercury. Faced with these regulations, the U.S. Gulf Coast oil industry has looked to foreign sources of low-mercury barite, primarily India and China. These sources tend to have high-grade barite deposits and relatively inexpensive domestic transportation costs; as of late, however, U.S. purchasers have been forced to pay increasing costs for shipping to U.S. grinding plants. The objective of this project was to demonstrate two mercury removal techniques for high-mercury barite sources. Two barite samples of unique origins underwent processing to reduce mercury to required levels. The chemical treatment with dilute acid removed a portion of the mercury in both barite samples. The desired concentration of 1 mg/kg was achieved in both barite samples. An economic analysis indicates that thermal removal of mercury would not significantly add to the cost of barite processing, making higher-mercury barite a viable alternative to more expensive barite sources that contain lower concentrations of mercury.

  6. Mercury removal from incineration flue gas by organic and inorganic adsorbents.

    PubMed

    Jurng, Jongsoo; Lee, Tai Gyu; Lee, Gyo Woo; Lee, Sung-Jun; Kim, Byung Hwa; Seier, Jochen

    2002-06-01

    Experiments were performed to investigate various adsorbents for their mercury removal capabilities from incineration flue gases. Four different materials were tested; Zeolite, Bentonite, activated carbon (AC), and wood char. Real incineration off-gas and in-lab simulated combustion flue gases (N2 + Hg) were used. Three cylindrical-shaped sorbent columns with 5 cm in diameter and 20 cm in length were used. The gas flow rate was fixed at 660 l/h at all times. Concentrations of NO, CO, O2, CO2, SO2, H2O, HCl, and mercury were continuously monitored. Mercury removal efficiencies of natural Zeolite and Bentonite were found to be much lower than those of the referenced AC. Amount of Hg removed were 9.2 and 7.4 microg/g of Zeolite and Bentonite, respectively. Removal efficiencies of each layer consisted of inorganic adsorbents were no higher than 7%. No significant improvement was observed with sulfur impregnation onto the inorganic adsorbents. Organic adsorbents (wood char and AC) showed much higher mercury removal efficiencies than those of inorganic ones (Zeolite and Bentonite). Mercury removal efficiency of wood char reached over 95% in the first layer, showing almost same effectiveness as AC which currently may be the most effective adsorbents for mercury. Amount of mercury captured by wood char was approximately 0.6 mg/g of wood char, close to the amount captured by AC tested in this study. Hence, wood char, made from the waste woods through a gasification process, should be considered as a possible alternative to relatively expensive AC. PMID:12108697

  7. Fibrous polymer-grafted chitosan/clay composite beads as a carrier for immobilization of papain and its usability for mercury elimination.

    PubMed

    Metin, Ayşegül Ülkü; Alver, Erol

    2016-07-01

    Papain, which is an industrially important enzyme, has been immobilized on fibrous polymer-modified composite beads, namely poly(methacrylic acid)-grafted chitosan/clay. Characterization studies have been done using FTIR and SEM analysis. Operating parameters such as pH and initial concentration of papain have been varied to obtain the finest papain immobilized polymer-modified composite beads. The immobilization capacity of composite beads has been determined as 34.47 ± 1.18 (n = 3) mg/g. The proteolytic activity of immobilized papain was operated using bovine serum albumin (BSA) and maximum velocity (V max) and Michaelis-Menten constant (Km) values of the free and immobilized enzymes were determined using Lineweaver-Burk and Eadie-Hofstee equations. Usability of papain immobilized polymer-modified composite beads as adsorbents for the elimination of mercury was investigated. The maximum removal capacity of PIPMC beads has been found to be 4.88 ± 0.21 mg Hg/g when the initial metal concentration and weight of polymer-modified composite beads were 50 mg/L and 0.04 g at pH 7, respectively. Mercury removal performance of the papain immobilized polymer-modified composite beads was investigated in conjunction with Cu (II), Zn (II) and Cd (II) ions. The mercury adsorption capacity of papain immobilized polymer-modified composite beads was a slight reduction from 1.15 to 0.89 mg/g in presence of multiple metal salts. PMID:27013506

  8. The removal of mercury from solid mixed waste using chemical leaching processes

    SciTech Connect

    Gates, D.D.; Chao, K.K.; Cameron, P.A.

    1995-07-01

    The focus of this research was to evaluate chemical leaching as a technique to treat soils, sediments, and glass contaminated with either elemental mercury or a combination of several mercury species. Potassium iodide/iodine solutions were investigated as chemical leaching agents for contaminated soils and sediments. Clean, synthetic soil material and surrogate storm sewer sediments contaminated with mercury were treated with KI/I{sub 2} solutions. It was observed that these leaching solutions could reduce the mercury concentration in soil and sediments by 99.8%. Evaluation of selected posttreatment sediment samples revealed that leachable mercury levels in the treated solids exceeded RCRA requirements. The results of these studies suggest that KI/I{sub 2} leaching is a treatment process that can be used to remove large quantities of mercury from contaminated soils and sediments and may be the only treatment required if treatment goals are established on Hg residual concentrations in solid matrices. Fluorescent bulbs were used to simulate mercury contaminated glass mixed waste. To achieve mercury contamination levels similar to those found in larger bulbs such as those used in DOE facilities a small amount of Hg was added to the crushed bulbs. The most effective agents for leaching mercury from the crushed fluorescent bulbs were KI/I{sub 2}, NaOCl, and NaBr + acid. Radionuclide surrogates were added to both the EPA synthetic soil material and the crushed fluorescent bulbs to determine the fate of radionuclides following chemical leaching with the leaching agents determined to be the most promising. These experiments revealed that although over 98% of the dosed mercury solubilized and was found in the leaching solution, no Cerium was measured in the posttreatment leaching solution. This finding suggest that Uranium, for which Ce was used as a surrogate, would not solubilize during leaching of mercury contaminated soil or glass.

  9. Removing mercury from coal emissions: options for ash-friendly technologies

    SciTech Connect

    Sager, J.

    2009-07-01

    The article gives a brief description of techniques to remove mercury emitted from coal-fired power plants and discusses environmental considerations associated with the effect of emission controls on coal fly ash. Techniques covered include use of injected mercury sorbents (activated carbon, metal oxide catalysts, MerCAP{trademark} and MercScreen{trademark}) and fuel cleaning. Technologies currently being researched are mentioned. 8 refs.

  10. Statistical estimate of mercury removal efficiencies for air pollution control devices of municipal solid waste incinerators.

    PubMed

    Takahashi, Fumitake; Kida, Akiko; Shimaoka, Takayuki

    2010-10-15

    Although representative removal efficiencies of gaseous mercury for air pollution control devices (APCDs) are important to prepare more reliable atmospheric emission inventories of mercury, they have been still uncertain because they depend sensitively on many factors like the type of APCDs, gas temperature, and mercury speciation. In this study, representative removal efficiencies of gaseous mercury for several types of APCDs of municipal solid waste incineration (MSWI) were offered using a statistical method. 534 data of mercury removal efficiencies for APCDs used in MSWI were collected. APCDs were categorized as fixed-bed absorber (FA), wet scrubber (WS), electrostatic precipitator (ESP), and fabric filter (FF), and their hybrid systems. Data series of all APCD types had Gaussian log-normality. The average removal efficiency with a 95% confidence interval for each APCD was estimated. The FA, WS, and FF with carbon and/or dry sorbent injection systems had 75% to 82% average removal efficiencies. On the other hand, the ESP with/without dry sorbent injection had lower removal efficiencies of up to 22%. The type of dry sorbent injection in the FF system, dry or semi-dry, did not make more than 1% difference to the removal efficiency. The injection of activated carbon and carbon-containing fly ash in the FF system made less than 3% difference. Estimation errors of removal efficiency were especially high for the ESP. The national average of removal efficiency of APCDs in Japanese MSWI plants was estimated on the basis of incineration capacity. Owing to the replacement of old APCDs for dioxin control, the national average removal efficiency increased from 34.5% in 1991 to 92.5% in 2003. This resulted in an additional reduction of about 0.86Mg emission in 2003. Further study using the methodology in this study to other important emission sources like coal-fired power plants will contribute to better emission inventories. PMID:20713298

  11. Regenerable cobalt oxide loaded magnetosphere catalyst from fly ash for mercury removal in coal combustion flue gas.

    PubMed

    Yang, Jianping; Zhao, Yongchun; Zhang, Junying; Zheng, Chuguang

    2014-12-16

    To remove Hg(0) in coal combustion flue gas and eliminate secondary mercury pollution of the spent catalyst, a new regenerable magnetic catalyst based on cobalt oxide loaded magnetospheres from fly ash (Co-MF) was developed. The catalyst, with an optimal loading of 5.8% cobalt species, attained approximately 95% Hg(0) removal efficiency at 150 °C under simulated flue gas atmosphere. O2 could enhance the Hg(0) removal activity of magnetospheres catalyst via the Mars-Maessen mechanism. SO2 displayed an inhibitive effect on Hg(0) removal capacity. NO with lower concentration could promote the Hg(0) removal efficiency. However, when increasing the NO concentration to 300 ppm, a slightly inhibitive effect of NO was observed. In the presence of 10 ppm of HCl, greater than 95.5% Hg(0) removal efficiency was attained, which was attributed to the formation of active chlorine species on the surface. H2O presented a seriously inhibitive effect on Hg(0) removal efficiency. Repeated oxidation-regeneration cycles demonstrated that the spent Co-MF catalyst could be regenerated effectively via thermally treated at 400 °C for 2 h. PMID:25403026

  12. THE ADVANTAGE OF ILLINOIS COAL FOR FGD REMOVAL OF MERCURY

    EPA Science Inventory

    The paper gives results of an investigation conducted to characterize and modify mercury (Hg) speciation in Illinois coal combustion flue gas so that a Hg control strategy can be implemented in conventional flue gas desulfurization (FGD) units. Hg, in trace concentration in coal,...

  13. Possibilities of mercury removal in the dry flue gas cleaning lines of solid waste incineration units.

    PubMed

    Svoboda, Karel; Hartman, Miloslav; Šyc, Michal; Pohořelý, Michael; Kameníková, Petra; Jeremiáš, Michal; Durda, Tomáš

    2016-01-15

    Dry methods of the flue gas cleaning (for HCl and SO2 removal) are useful particularly in smaller solid waste incineration units. The amount and forms of mercury emissions depend on waste (fuel) composition, content of mercury and chlorine and on the entire process of the flue gas cleaning. In the case of high HCl/total Hg molar ratio in the flue gas, the majority (usually 70-90%) of mercury is present in the form of HgCl2 and a smaller amount in the form of mercury vapors at higher temperatures. Removal of both main forms of mercury from the flue gas is dependent on chemical reactions and sorption processes at the temperatures below approx. 340 °C. Significant part of HgCl2 and a small part of elemental Hg vapors can be adsorbed on fly ash and solid particle in the air pollution control (APC) processes, which are removed in dust filters. Injection of non-impregnated active carbon (AC) or activated lignite coke particles is able to remove mainly the oxidized Hg(2+) compounds. Vapors of metallic Hg(o) are adsorbed relatively weakly. Much better chemisorption of Hg(o) together with higher sorbent capacity is achieved by AC-based sorbents impregnated with sulfur, alkali poly-sulfides, ferric chloride, etc. Inorganic sorbents with the same or similar chemical impregnation are also applicable for deeper Hg(o) removal (over 85%). SCR catalysts convert part of Hg(o) into oxidized compounds (HgO, HgCl2, etc.) contributing to more efficient Hg removal, but excess of NH3 has a negative effect. Both forms, elemental Hg(o) and HgCl2, can be converted into HgS particles by reacting with droplets/aerosol of poly-sulfides solutions/solids in flue gas. Mercury captured in the form of water insoluble HgS is more advantageous in the disposal of solid waste from APC processes. Four selected options of the dry flue gas cleaning with mercury removal are analyzed, assessed and compared (in terms of efficiency of Hg-emission reduction and costs) with wet methods and retrofits for more

  14. Synergistic mercury removal by conventional pollutant control strategies for coal-fired power plants in China.

    PubMed

    Wang, Shuxiao; Zhang, Lei; Wu, Ye; Ancora, Maria Pia; Zhao, Yu; Hao, Jiming

    2010-06-01

    China's 11th 5-yr plan has regulated total sulfur dioxide (SO2) emissions by installing flue gas desulfurization (FGD) devices and shutting down small thermal power units. These control measures will not only significantly reduce the emission of conventional pollutants but also benefit the reduction of mercury emissions from coal-fired power plants. This paper uses the emission factor method to estimate the efficiencies of these measures on mercury emission abatement. From 2005 to 2010, coal consumption in power plants will increase by 59%; however, the mercury emission will only rise from 141 to 155 t, with an increase of 10%. The average emission rate of mercury from coal burning will decrease from 126 mg Hg/t of coal to 87 mg Hg/t of coal. The effects of the three desulfurization measures were assessed and show that wet FGD will play an important role in mercury removal. Mercury emissions in 2015 and 2020 are also projected under different policy scenarios. Under the most probable scenario, the total mercury emission in coal-fired power plants in China will decrease to 130 t by 2020, which will benefit from the rapid installation of fabric filters and selective catalytic reduction. PMID:20564998

  15. Reduction and removal of mercury from water using Arginine-modified TiO{sub 2}.

    SciTech Connect

    Skubal, L. R.; Meshkov, N. K.; Energy Systems

    2002-05-31

    The photocatalytic removal of mercury(II) ions from water was investigated using titanium dioxide (TiO{sub 2}) nanoparticles (45 A in diameter) surface-modified with arginine (ARG). TiO{sub 2} sols were prepared by the controlled hydrolysis of titanium tetrachloride. ARG-modified TiO{sub 2} was placed in water and purged anoxically with an inert gas. Suspensions were spiked with elevated mercury concentrations (from mercuric chloride) and equilibrated for 10 min in darkness (with continuous stirring). Suspensions were either illuminated with 253.7 nm light or kept in darkness while mixing continuously. Samples were periodically withdrawn from the reactor via syringe and filtered anoxically. Precipitate collected on the filters was tested for elemental mercury; filtrate was analyzed for mercury using cold vapor atomic absorption spectrometry. Results showed that in the absence of light, approximately 60% of initial mercury could be sorbed onto the ARG-modified TiO{sub 2} [ARG (1.67x10{sup -3} M), TiO{sub 2}(5.00x10{sup -3} M)]. ARG-modified TiO2 removed greater than 99.9% of the initial mercury (150 ppm) present in solution within 128 min of illumination through sorption and reduction processes. This removal time was reduced to 32 min when methanol was added as a hole scavenger. These sorption and reduction processes were catalytic in nature. The presence of 30 ppm iron(III) greatly inhibits both the sorption and the reduction of mercury on ARG-modified TiO{sub 2}.

  16. A Non-Mercury Thermometer Alternative for Use in Older Melting Point Apparatuses

    ERIC Educational Resources Information Center

    Ongley, Lois K.; Kern, Clayton S.; Woods, Barry W.

    2008-01-01

    The State of Maine seeks to eliminate most mercury use. This includes removing mercury thermometers from secondary schools and discouraging Hg use in other educational institutions. Alternatives to mercury thermometers in chemical laboratory work include non-mercury thermometers, temperature probes, and thermocouples. In organic chemistry mercury…

  17. Evaluation of Selective Ion Exchange Resins for Removal of Mercury from the H-Area Water Treatment Unit

    SciTech Connect

    Serkiz, S.M.

    2000-09-05

    This study investigated the ability of seven ion exchange (IX) resins, some of which were mercury specific, to remove mercury in H-Area WTU waters from three sources (Reverse Osmosis (RO) Feed, RO Permeate from Train A, and a mercury ''hot spot'' extraction well HEX 18). Seven ion exchange resins, including ResinTech CG8 and Dowex 21K (the cation and anion exchange resins currently used at the H-Area WTU) were screened against five alternative ion exchange materials plus an experimental blank. Mercury decontamination factors (DFs), mercury breakthrough, and post-test contaminant concentrations of IX resins were determined for each IX material tested.

  18. Fate of soluble uranium in the I{sub 2}/KI leaching process for mercury removal

    SciTech Connect

    Bostick, W.D.; Davis, W.H.; Jarabek, R.J.

    1997-09-01

    General Electric Corporation has developed an extraction and recovery system for mercury, based upon the use of iodine (oxidant) and iodide ion (complexing agent). This system has been proposed for application to select mercury-contaminated mixed waste (i.e., waste containing radionuclides as well as other hazardous constituents), which have been generated by historic activities in support of US Department of Energy (DOE) missions. This system is compared to a system utilizing hypochlorite and chloride ions for removal of mercury and uranium from a sample of authentic mixed waste sludge. Relative to the hypochlorite (bleach) system, the iodine system mobilized more mercury and less uranium from the sludge. An engineering flowsheet has been developed to treat spent iodine-containing extraction medium, allowing the system to be recycled. The fate of soluble uranium in this series of treatment unit operations was monitored by tracing isotopically-enriched uranyl ion into simulated spent extraction medium. Treatment with use of elemental iron is shown to remove > 85% of the traced uranium while concurrently reducing excess iodine to the iodide ion. The next unit operation, adjustment of the solution pH to a value near 12 by the addition of lime slurry to form a metal-laden sludge phase (an operation referred to as lime-softening), removed an additional 57% of soluble uranium activity, for an over-all removal efficiency of {approximately} 96%. However, the precipitated solids did not settle well, and some iodide reagent is held up in the wet filtercake.

  19. REMOVAL OF MERCURY FROM CONTAMINATED SOILS AT THE PAVLODAR CHEMICAL PLANT.

    SciTech Connect

    KHRAPUNOV, V. YE.; ISAKOVA, R.A.; LEVINTOV, B.L.; KALB, P.D.; KAMBEROV, I.M.; TREBUKHOV, A.

    2004-09-25

    Soils beneath and adjacent to the Pavlodar Chemical Plant in Kazakhstan have been contaminated with elemental mercury as a result of chlor alkali processing using mercury cathode cell technology. The work described in this paper was conducted in preparation for a demonstration of a technology to remove the mercury from the contaminated soils using a vacuum assisted thermal distillation process. The process can operate at temperatures from 250-500 C and pressures of 0.13kPa-1.33kPa. Following vaporization, the mercury vapor is cooled, condensed and concentrated back to liquid elemental mercury. It will then be treated using the Sulfur Polymer Stabilization/Solidification process developed at Brookhaven National Laboratory as described in a companion paper at this conference. The overall project objectives include chemical and physical characterization of the contaminated soils, study of the influence of the soil's physical-chemical and hydro dynamical characteristics on process parameters, and laboratory testing to optimize the mercury sublimation rate when heating in vacuum. Based on these laboratory and pilot-scale data, a full-scale production process will be designed for testing. This paper describes the soil characterization. This work is being sponsored by the International Science and Technology Center.

  20. Mercury Removal at Idaho National Engineering and Environmental Laboratory's New Waste Calcining Facility

    SciTech Connect

    Ashworth, Samuel Clay; Wood, R. A.; Taylor, D. D.; Sieme, D. D.

    2000-03-01

    Technologies were investigated to determine viable processes for removing mercury from the calciner (NWCF) offgas system at the Idaho National Engineering and Environmental Laboratory. Technologies for gas phase and aqueous phase treatment were evaluated. The technologies determined are intended to meet EPA Maximum Achievable Control Technology (MACT) requirements under the Clean Air Act and Resource Conservation and Recovery Act (RCRA). Currently, mercury accumulation in the calciner off-gas scrubbing system is transferred to the tank farm. These transfers lead to accumulation in the liquid heels of the tanks. The principal objective for aqueous phase mercury removal is heel mercury reduction. The system presents a challenge to traditional methods because of the presence of nitrogen oxides in the gas phase and high nitric acid in the aqueous scrubbing solution. Many old and new technologies were evaluated including sorbents and absorption in the gas phase and ion exchange, membranes/sorption, galvanic methods, and UV reduction in the aqueous phase. Process modifications and feed pre-treatment were also evaluated. Various properties of mercury and its compounds were summarized and speciation was predicted based on thermodynamics. Three systems (process modification, NOxidizer combustor, and electrochemical aqueous phase treatment) and additional technology testing were recommended.

  1. Mercury removal at Idaho National Engineering and Environmental Laboratory's New Waste Calcining Facility

    SciTech Connect

    S. C. Ashworth

    2000-02-27

    Technologies were investigated to determine viable processes for removing mercury from the calciner (NWCF) offgas system at the Idaho National Engineering and Environmental Laboratory. Technologies for gas phase and aqueous phase treatment were evaluated. The technologies determined are intended to meet EPA Maximum Achievable Control Technology (MACT) requirements under the Clean Air Act and Resource Conservation and Recovery Act (RCRA). Currently, mercury accumulation in the calciner off-gas scrubbing system is transferred to the tank farm. These transfers lead to accumulation in the liquid heels of the tanks. The principal objective for aqueous phase mercury removal is heel mercury reduction. The system presents a challenge to traditional methods because of the presence of nitrogen oxides in the gas phase and high nitric acid in the aqueous scrubbing solution. Many old and new technologies were evaluated including sorbents and absorption in the gas phase and ion exchange, membranes/sorption, galvanic methods, and UV reduction in the aqueous phase. Process modifications and feed pre-treatment were also evaluated. Various properties of mercury and its compounds were summarized and speciation was predicted based on thermodynamics. Three systems (process modification, NOxidizer combustor, and electrochemical aqueous phase treatment) and additional technology testing were recommended.

  2. MERCURY REMOVAL FROM DOE SOLID MIXED WASTE USING THE GEMEP(sm) TECHNOLOGY

    SciTech Connect

    1999-03-01

    Under the sponsorship of the Federal Energy Technology Center (FETC), Metcalf and Eddy (M and E), in association with General Electric Corporate Research and Development Center (GE-CRD), Colorado Minerals Research Institute (CMRI), and Oak Ridge National Laboratory (ORNL), conducted laboratory-scale and bench-scale tests of the General Electric Mercury Extraction Process technology on two mercury-contaminated mixed solid wastes from U. S. Department of Energy sites: sediment from the East Fork of Poplar Creek, Oak Ridge (samples supplied by Oak Ridge National Laboratory), and drummed soils from Idaho National Environmental and Engineering Laboratory (INEEL). Fluorescent lamps provided by GE-CRD were also studied. The GEMEP technology, invented and patented by the General Electric Company, uses an extraction solution composed of aqueous potassium iodide plus iodine to remove mercury from soils and other wastes. The extraction solution is regenerated by chemical oxidation and reused, after the solubilized mercury is removed from solution by reducing it to the metallic state. The results of the laboratory- and bench-scale testing conducted for this project included: (1) GEMEP extraction tests to optimize extraction conditions and determine the extent of co-extraction of radionuclides; (2) pre-screening (pre-segregation) tests to determine if initial separation steps could be used effectively to reduce the volume of material needing GEMEP extraction; and (3) demonstration of the complete extraction, mercury recovery, and iodine recovery and regeneration process (known as locked-cycle testing).

  3. Improved chronic fatigue symptoms after removal of mercury in patient with increased mercury concentration in hair toxic mineral assay: a case.

    PubMed

    Shin, Sae-Ron; Han, A-Lum

    2012-09-01

    Clinical manifestations of chronic exposure to organic mercury usually have a gradual onset. As the primary target is the nervous system, chronic mercury exposure can cause symptoms such as fatigue, weakness, headache, and poor recall and concentration. In severe cases chronic exposure leads to intellectual deterioration and neurologic abnormality. Recent outbreaks of bovine spongiform encephalopathy and pathogenic avian influenza have increased fish consumption in Korea. Methyl-mercury, a type of organic mercury, is present in higher than normal ranges in the general Korean population. When we examine a patient with chronic fatigue, we assess his/her methyl-mercury concentrations in the body if environmental exposure such as excessive fish consumption is suspected. In the current case, we learned the patient had consumed many slices of raw tuna and was initially diagnosed with chronic fatigue syndrome. Therefore, we suspected that he was exposured to methyl-mercury and that the mercury concentration in his hair would be below the poisoning level identified by World Health Organization but above the normal range according to hair toxic mineral assay. Our patient's toxic chronic fatigue symptoms improved after he was given mercury removal therapy, indicating that he was correctly diagnosed with chronic exposure to organic mercury. PMID:23115707

  4. Mercury

    MedlinePlus

    ... button batteries. Mercury salts may be used in skin creams and ointments. It's also used in many industries. Mercury in the air settles into water. It can pass through the food chain and build up in ...

  5. Mercury

    MedlinePlus

    Mercury is an element that is found in air, water and soil. It has several forms. Metallic mercury is a shiny, silver-white, ... colorless, odorless gas. It also combines with other elements to form powders or crystals. Mercury is in ...

  6. NOVEL PROCESS FOR REMOVAL AND RECOVERY OF VAPOR-PHASE MERCURY

    SciTech Connect

    1998-10-20

    The purpose of this project is to investigate the application of a sorbent-based process for removing and recovering mercury in the flue gas of coal-fired power plants. The process is based on the sorption of mercury by noble metals and the regeneration of the sorbent by thermal means, recovering the desorbed mercury for recycling. ADA Technologies holds a patent on this process (US 5,409,522) and has tested it under conditions typical of municipal waste incinerators. In this process, the noble metal sorbent is regenerated thermally, and the mercury is recovered for commercial recycle. Consequently, ADA has adopted the name ''Mercu-RE'' to describe its process. ADA has been testing its process under conditions typical of coal-fired power plants where the mercury concentration is low (below 10 {micro}g/m{sup 3}) and little pressure drop can be tolerated. Methods of accommodating the Mercu-RE process to the circumstances and conditions of coal-fired power plants comprise the core of the program.

  7. Organ-specific accumulation, transportation, and elimination of methylmercury and inorganic mercury in a low Hg accumulating fish.

    PubMed

    Peng, Xiaoyan; Liu, Fengjie; Wang, Wen-Xiong

    2016-08-01

    Low mercury (Hg) concentrations down to several nanograms Hg per gram of wet tissue are documented in certain fish species such as herbivorous fish, and the underlying mechanisms remain speculative. In the present study, bioaccumulation and depuration patterns of inorganic Hg(II) and methylmercury (MeHg) in a herbivorous rabbitfish Siganus canaliculatus were investigated at organ and subcellular levels following waterborne or dietary exposures. The results showed that the efflux rate constants of Hg(II) and MeHg were 0.104 d(-1) and 0.024 d(-1) , respectively, and are probably the highest rate constants recorded in fish thus far. The dietary MeHg assimilation efficiency (68%) was much lower than those in other fish species (∼90%). The predominant distribution of MeHg in fish muscle was attributable to negligible elimination of MeHg from muscle (< 0) and efficient elimination of MeHg from gills (0.12 d(-1) ), liver (0.17 d(-1) ), and intestine (0.20 d(-1) ), as well as efficient transportation of MeHg from other organs into muscle. In contrast, Hg(II) was much more slowly distributed into muscle but was efficiently eliminated by the intestine (0.13 d(-1) ). Subcellular distribution indicated that some specific membrane proteins in muscle were the primary binding pools for MeHg, and both metallothionein-like proteins and Hg-rich granules were the important components in eliminating both MeHg and Hg(II). Overall, the present study's results suggest that the low tissue Hg concentration in the rabbitfish was partly explained by its unique biokinetics. Environ Toxicol Chem 2016;35:2074-2083. © 2016 SETAC. PMID:26756981

  8. Simulation of mercury capture by activated carbon injection in incinerator flue gas. 2. Fabric filter removal.

    PubMed

    Scala, F

    2001-11-01

    Following a companion paper focused on the in-duct mercury capture in incinerator flue gas by powdered activated carbon injection, this paper is concerned with the additional mercury capture on the fabric filter cake, relevant to baghouse equipped facilities. A detailed model is presented for this process, based on material balances on mercury in both gaseous and adsorbed phases along the growing filter cake and inside the activated carbon particles,taking into account mass transfer resistances and adsorption kinetics. Several sorbents of practical interest have been considered, whose parameters have been evaluated from available literature data. The values and range of the operating variables have been chosen in order to simulate typical incinerators operating conditions. Results of simulations indicate that, contrary to the in-duct removal process, high mercury removal efficiencies can be obtained with moderate sorbent consumption, as a consequence of the effective gas/sorbent contacting on the filter. Satisfactory utilization of the sorbents is predicted, especially at long filtration times. The sorbent feed rate can be minimized by using a reactive sorbent and by lowering the filter temperature as much as possible. Minor benefits can be obtained also by decreasing the sorbent particle size and by increasing the cleaning cycle time of the baghouse compartments. Reverse-flow baghouses were more efficient than pulse-jet baghouses, while smoother operation can be obtained by increasing the number of baghouse compartments. Model results are compared with available relevant full scale data. PMID:11718360

  9. Removal and accumulation of mercury by aquatic macrophytes from an open cast coal mine effluent.

    PubMed

    Mishra, Virendra Kumar; Tripathi, B D; Kim, Ki-Hyun

    2009-12-30

    In this study, the mercury (Hg) removal capacities of two aquatic macrophytes, Pistia stratiotes and Azolla pinnata, were investigated against the coal mining effluent. These plants reduced mercury from the effluent via rhizofiltration and subsequent accumulation in plant. The removal rate of P. stratiotes and A. pinnata was 80% and 68%, respectively, after 21 days of exposure to the effluent containing 10 microg L(-1) of Hg. As mercury from the effluent was accumulated in the root and shoot tissues of both aquatic macrophytes, they were proven to be a root accumulator with a translocation factor of less than one during the entire study. The decreasing Hg content in effluent (from 10 to 2.0 microg L(-1)) was reflected by its accumulation in roots (0.57+/-0.02 mg g(-1) in P. stratiotes) and leaves of the experimental plants (0.42+/-0.01 mg g(-1), P. stratiotes). As a result, Hg concentrations in the coal mining effluent were tightly associated with those observed from macrophytes. Considering the high removal efficiencies of Hg by these aquatic macrophytes, these plants can be recommended for the actual treatment of Hg-containing waste waters. PMID:19665290

  10. Preparation, characterization, and application of modified chitosan sorbents for elemental mercury removal

    SciTech Connect

    Zhang, A.C.; Xiang, J.; Sun, L.S.; Hu, S.; Li, P.S.; Shi, J.M.; Fu, P.; Su, S.

    2009-05-15

    A series of raw, iodine (bromide) or/and sulfuric acid-modified chitosan sorbents were synthesized and comprehensively characterized by N{sub 2} isotherm adsorption/desorption method, TGA, FTIR, XRD, and XPS et al. Adsorption experiments of vapor-phase elemental mercury (Hg{sup 0}) were studied using the sorbents in a laboratory-scale fixed-bed reactor. The results revealed that porosities and specific surface areas of the sorbents decreased after modification. The sorbents operated stably at flue-gas temperature below 140{sup o}C. The chemical reactions of iodine and sulfate ion with the amide of chitosan occurred, and the I{sub 2} was found in the sorbents due to the presence of H{sub 2}SO{sub 4}. Fixed-bed adsorber tests showed that compared to raw chitosan, the bromide or iodine-modified chitosan could promote the efficiency of Hg{sub 0} capture more or less. Mercury removal efficiency could be significantly promoted when an appropriate content of H{sub 2}SO{sub 4} was added, and the iodine and H{sub 2}SO{sub 4} modified sorbents almost had a mercury removal efficiency of 100% for 3 h. The presence of moisture can increase the sorbent's capacity for mercury uptake due to the existence of active sites, such as sulfonate and amino group. The mercury breakthrough of modified chitosan sorbents decreased with increasing temperature. A reaction scheme that could explain the experimental results was presumed based on the characterizations and adsorption study.

  11. A study on removal of elemental mercury in flue gas using fenton solution.

    PubMed

    Liu, Yangxian; Wang, Yan; Wang, Qian; Pan, Jianfeng; Zhang, Yongchun; Zhou, Jianfei; Zhang, Jun

    2015-07-15

    A novel technique on oxidation-separation of elemental mercury (Hg(0)) in flue gas using Fenton solution in a bubbling reactor was proposed. The effects of several process parameters (H2O2 concentration, Hg(0) inlet concentration, Fe(2+) concentration, solution temperature, solution pH, gas flow) and several flue gas components (NO, SO2, O2, CO2, inorganic ions and particulate matters on Hg(0) removal were studied. The results indicate that H2O2 concentration, Fe(2+) concentration, solution pH and gas flow have great effects on Hg(0) removal. Solution temperature, Hg(0), NO, SO2, CO3(2-) and HCO3(-) concentrations also have significant effects on Hg(0) removal. However, Cl(-), SO4(2-), NO3(-), O2 and CO2 concentrations only have slight effects on Hg(0) removal. Furthermore, reaction mechanism of Hg(0) removal and simultaneous removal process of Hg(0), NO and SO2 were also studied. Hg(0) is removed by oxidation of OH and oxidation of H2O2. The simultaneous removal efficiencies of 100% for SO2, 100% for Hg(0) and 88.3% for NO were obtained under optimal test conditions. The results demonstrated the feasibility of Hg(0) removal and simultaneous removal of Hg(0), SO2 and NO using Fenton solution in a bubbling reactor. PMID:25804791

  12. Removal of element mercury by medicine residue derived biochars in presence of various gas compositions.

    PubMed

    Li, Guoliang; Shen, Boxiong; Li, Yongwang; Zhao, Bin; Wang, Fumei; He, Chuan; Wang, Yinyin; Zhang, Min

    2015-11-15

    Pyrolyzed biochars from an industrial medicinal residue waste were modified by microwave activation and NH4Cl impregnation. Mercury adsorption of different modified biochars was investigated in a quartz fixed-bed reactor. The results indicated that both physisorption and chemisorption of Hg(0) occurred on the surface of M6WN5 which was modified both microwave and 5wt.% NH4Cl loading, and exothermic chemisorption process was a dominant route for Hg(0) removal. Microwave activation improved pore properties and NH4Cl impregnation introduced good active sites for biochars. The presence of NO and O2 increased Hg(0) adsorption whereas H2O inhibited Hg(0) adsorption greatly. A converse effect of SO2 was observed on Hg(0) removal, namely, low concentration of SO2 promoted Hg(0) removal obviously whereas high concentration of SO2 suppressed Hg(0) removal. The Hg(0) removal by M6WN5 was mainly due to the reaction of the C−Cl with Hg(0) to form HgCl2, and the active state of C−Cl(*) groups might be an intermediate group in this process. Thermodynamic analysis showed that mercury adsorption by the biochars was exothermic process and apparent adsorption energy was 43.3 kJ/mol in the range of chemisorption. In spite of low specific surface area, M6WN5 proved to be a promising Hg(0) sorbent in flue gas when compared with other sorbents. PMID:26051992

  13. Mercury removals by existing pollutants control devices of four coal-fired power plants in China.

    PubMed

    Wang, Juan; Wang, Wenhua; Xu, Wei; Wang, Xiaohao; Zhao, Song

    2011-01-01

    The mercury removals by existing pollution control devices and the mass balances of mercury in four coal-fired power plants of China were carried out based on a measurement method with the aluminum matrix sorbent. All the plants are equipped with a cold-side electrostatic precipitator (ESP) and a wet flue gas desulfurization (FGD) in series. During the course of coal stream, the samples, such as coal, bottom ash, fly ash, gypsum and flue gas, were collected. The Hg concentrations in coals were measured by CVAAS after appropriate preparation and acid digestion. Other solid samples were measured by the RA-915+ Zeeman Mercury Spectrometer. The vapor phase Hg was collected by a sorbent trap from flue gas and then measured using CVAAS followed by acid leaching. The mercury mass balances were estimated in this study were 91.6%, 77.1%, 118% and 85.8% for the four power plants, respectively. The total Hg concentrations in the stack gas were ranged from 1.56-5.95 microg/m3. The relative distribution of Hg in bottom ash, ESP, WFGD and stack discharged were ranged between 0.110%-2.50%, 2.17%-23.4%, 2.21%-87.1%, and 21.8%-72.7%, respectively. The distribution profiles were varied with the coal type and the operation conditions. The Hg in flue gas could be removed by ESP and FGD systems with an average removal efficiency of 51.8%. The calculated average emission factor was 0.066 g/ton and much lower than the results obtained ten years ago. PMID:22432308

  14. Removal of Mercury from the Off-Gas from Thermal Treatment of Radioactive Liquid Waste

    SciTech Connect

    Deldebbio, John Anthony; Olson, Lonnie Gene

    2001-05-01

    Acidic, radioactive wastes with a high nitrate concentration, and containing mercury are currently being stored at the Idaho Nuclear Technology and Engineering Center (INTEC). In the past, these wastes were converted into a dry, granular solid by a high temperature fluidized-bed calcination process. In the future, the calcined solids may be immobilized by a vitrification process prior to disposal. It has been proposed that a vitrification facility be built to treat the acidic wastes, as well as the calcined solids. As was the case with the calcination process, NOx levels in the vitrification off-gas are expected to be high, and mercury emissions are expected to exceed the Maximum Control Technology (MACT) limits. Mitigation of mercury emissions by wet scrubbing, followed by adsorption onto activated carbon is being investigated. Scoping tests with sulfur-impregnated activated carbon, KCl-impregnated activated carbon and non-impregnated activated carbon were conducted with a test gas containing1% NO2, 28% H2O, 4% O2 and 67% N2. Average removal efficiencies for Hgo and HgCl2 were 100 ± 2.5% and 99 ± 3.6% respectively, for sulfur-impregnated carbon. The KCl-impregnated carbon removed 99 ± 4.6% HgCl2. The removal efficiency of the non-impregnated carbon was 99 ± 3.6% for HgCl2. No short-term detrimental effects due to NO2 and H2O were observed. These results indicate that, placed downstream of a wet scrubber, an activated carbon adsorption bed has the potential of reducing mercury levels sufficiently to enable compliance with the MACT limit. Long-term exposure tests, and bed size optimization studies are planned for the future.

  15. Removal of bone in CT angiography of the cervical arteries by piecewise matched mask bone elimination

    SciTech Connect

    Straten, Marcel van; Venema, Henk W.; Streekstra, Geert J.; Majoie, Charles B.L.M.; Heeten, Gerard J. den; Grimbergen, Cornelis A.

    2004-10-01

    In maximum intensity projection (MIP) images of CT angiography (CTA) scans, the arteries are often obscured by bone. A bone removal method is presented that uses an additional, nonenhanced scan to create a mask of the bone by thresholding and dilation. After registration of the CTA scan and the additional scan, the bone in the CTA scan is masked. As the cervical area contains bones that can move with respect to each other, these bones are separated first using a watershed algorithm, and then registered individually. A phantom study was performed to evaluate and quantify the tradeoff between the removal of the bone and the preservation of the arteries contiguous to the bone. The influence of algorithm parameters and scan parameters was studied. The method was clinically evaluated with data sets of 35 patients. Best results were obtained with a threshold of 150 HU and a dilation of 8 in-plane voxels and two out-of-plane voxels. The mean width of the soft tissue layer, which is also masked, was approximately 1 mm. The mAs value of the nonenhanced scan could be reduced from 250 mAs to 65 mAs without a loss of quality. In 32 cases the bones were registered correctly and removed completely. In three cases the bone separation was not completely successful, and consequently the bone was not completely removed. The piecewise matched mask bone elimination method proved to be able to obtain MIP images of the cervical arteries free from overprojecting bone in a fully automatic way and with only a slight increase of radiation dose.

  16. Removal of bone in CT angiography by multiscale matched mask bone elimination

    SciTech Connect

    Gratama van Andel, H. A. F.; Venema, H. W.; Streekstra, G. J.; Straten, M. van; Majoie, C. B. L. M.; Heeten, G. J. den; Grimbergen, C. A.

    2007-10-15

    For clear visualization of vessels in CT angiography (CTA) images of the head and neck using maximum intensity projection (MIP) or volume rendering (VR) bone has to be removed. In the past we presented a fully automatic method to mask the bone [matched mask bone elimination (MMBE)] for this purpose. A drawback is that vessels adjacent to bone may be partly masked as well. We propose a modification, multiscale MMBE, which reduces this problem by using images at two scales: a higher resolution than usual for image processing and a lower resolution to which the processed images are transformed for use in the diagnostic process. A higher in-plane resolution is obtained by the use of a sharper reconstruction kernel. The out-of-plane resolution is improved by deconvolution or by scanning with narrower collimation. The quality of the mask that is used to remove bone is improved by using images at both scales. After masking, the desired resolution for the normal clinical use of the images is obtained by blurring with Gaussian kernels of appropriate widths. Both methods (multiscale and original) were compared in a phantom study and with clinical CTA data sets. With the multiscale approach the width of the strip of soft tissue adjacent to the bone that is masked can be reduced from 1.0 to 0.2 mm without reducing the quality of the bone removal. The clinical examples show that vessels adjacent to bone are less affected and therefore better visible. Images processed with multiscale MMBE have a slightly higher noise level or slightly reduced resolution compared with images processed by the original method and the reconstruction and processing time is also somewhat increased. Nevertheless, multiscale MMBE offers a way to remove bone automatically from CT angiography images without affecting the integrity of the blood vessels. The overall image quality of MIP or VR images is substantially improved relative to images processed with the original MMBE method.

  17. Removal of bone in CT angiography of the cervical arteries by piecewise matched mask bone elimination.

    PubMed

    van Straten, Marcel; Venema, Henk W; Streekstra, Geert J; Majoie, Charles B L M; den Heeten, Gerard J; Grimbergen, Cornelis A

    2004-10-01

    In maximum intensity projection (MIP) images of CT angiography (CTA) scans, the arteries are often obscured by bone. A bone removal method is presented that uses an additional, nonenhanced scan to create a mask of the bone by thresholding and dilation. After registration of the CTA scan and the additional scan, the bone in the CTA scan is masked. As the cervical area contains bones that can move with respect to each other, these bones are separated first using a watershed algorithm, and then registered individually. A phantom study was performed to evaluate and quantify the tradeoff between the removal of the bone and the preservation of the arteries contiguous to the bone. The influence of algorithm parameters and scan parameters was studied. The method was clinically evaluated with data sets of 35 patients. Best results were obtained with a threshold of 150 HU and a dilation of 8 in-plane voxels and two out-of-plane voxels. The mean width of the soft tissue layer, which is also masked, was approximately 1 mm. The mAs value of the nonenhanced scan could be reduced from 250 mAs to 65 mAs without a loss of quality. In 32 cases the bones were registered correctly and removed completely. In three cases the bone separation was not completely successful, and consequently the bone was not completely removed. The piecewise matched mask bone elimination method proved to be able to obtain MIP images of the cervical arteries free from overprojecting bone in a fully automatic way and with only a slight increase of radiation dose. PMID:15543801

  18. Removal of mercury from solids using the potassium iodide/iodine leaching process

    SciTech Connect

    Klasson, K.T.; Koran, L.J. Jr.; Gates, D.D.; Cameron, P.A.

    1997-12-01

    Potassium iodide (KI) and iodine (I{sub 2}) leaching solutions have been evaluated for use in a process for removing mercury from contaminated mixed waste solids. Most of the experimental work was completed using surrogate waste. During the last quarter of fiscal year 1995, this process was evaluated using an actual mixed waste (storm sewer sediment from the Oak Ridge Y-12 Site). The mercury content of the storm sewer sediment was measured and determined to be approximately 35,000 mg/kg. A solution consisting of 0.2 M I{sub 2} and 0.4 M KI proved to be the most effective leachant used in the experiments when applied for 2 to 4 h at ambient temperature. Over 98% of the mercury was removed from the storm sewer sediment using this solution. Iodine recovery and recycle of the leaching agent were also accomplished successfully. Mathematical model was used to predict the amount of secondary waste in the process. Both surrogate waste and actual waste were used to study the fate of radionuclides (uranium) in the leaching process.

  19. Simultaneous Removal of NOx and Mercury in Low Temperature Selective Catalytic and Adsorptive Reactor

    SciTech Connect

    Neville G. Pinto; Panagiotis G. Smirniotis

    2006-03-31

    The results of a 18-month investigation to advance the development of a novel Low Temperature Selective Catalytic and Adsorptive Reactor (LTSCAR), for the simultaneous removal of NO{sub x} and mercury (elemental and oxidized) from flue gases in a single unit operation located downstream of the particulate collectors, are reported. In the proposed LTSCAR, NO{sub x} removal is in a traditional SCR mode but at low temperature, and, uniquely, using carbon monoxide as a reductant. The concomitant capture of mercury in the unit is achieved through the incorporation of a novel chelating adsorbent. As conceptualized, the LTSCAR will be located downstream of the particulate collectors (flue gas temperature 140-160 C) and will be similar in structure to a conventional SCR. That is, it will have 3-4 beds that are loaded with catalyst and adsorbent allowing staged replacement of catalyst and adsorbent as required. Various Mn/TiO{sub 2} SCR catalysts were synthesized and evaluated for their ability to reduce NO at low temperature using CO as the reductant. It has been shown that with a suitably tailored catalyst more than 65% NO conversion with 100% N{sub 2} selectivity can be achieved, even at a high space velocity (SV) of 50,000 h-1 and in the presence of 2 v% H{sub 2}O. Three adsorbents for oxidized mercury were developed in this project with thermal stability in the required range. Based on detailed evaluations of their characteristics, the mercaptopropyltrimethoxysilane (MPTS) adsorbent was found to be most promising for the capture of oxidized mercury. This adsorbent has been shown to be thermally stable to 200 C. Fixed-bed evaluations in the targeted temperature range demonstrated effective removal of oxidized mercury from simulated flue gas at very high capacity ({approx}>58 mg Hg/g adsorbent). Extension of the capability of the adsorbent to elemental mercury capture was pursued with two independent approaches: incorporation of a novel nano-layer on the surface of the

  20. Temperature-programmed decomposition desorption of mercury species over activated carbon sorbents for mercury removal from coal-derived fuel gas

    SciTech Connect

    M. Azhar Uddin; Masaki Ozaki; Eiji Sasaoka; Shengji Wu

    2009-09-15

    The mercury (Hg{sup 0}) removal process for coal-derived fuel gas in the integrated gasification combined cycle (IGCC) process will be one of the important issues for the development of a clean and highly efficient coal power generation system. Recently, iron-based sorbents, such as iron oxide (Fe{sub 2}O{sub 3}), supported iron oxides on TiO{sub 2}, and iron sulfides, were proposed as active mercury sorbents. The H{sub 2}S is one of the main impurity compounds in coal-derived fuel gas; therefore, H{sub 2}S injection is not necessary in this system. HCl is also another impurity in coal-derived fuel gas. In this study, the contribution of HCl to the mercury removal from coal-derived fuel gas by a commercial activated carbon (AC) was studied using a temperature-programmed decomposition desorption (TPDD) technique. The TPDD technique was applied to understand the decomposition characteristics of the mercury species on the sorbents. The Hg{sup 0}-removal experiments were carried out in a laboratory-scale fixed-bed reactor at 80-300{sup o}C using simulated fuel gas and a commercial AC, and the TPDD experiments were carried out in a U-tube reactor in an inert carrier gas (He or N{sub 2}) after mercury removal. The following results were obtained from this study: (1) HCl contributed to the mercury removal from the coal-derived fuel gas by the AC. (2) The mercury species captured on the AC in the HCl{sup -} and H{sub 2}S-presence system was more stable than that of the H{sub 2}S-presence system. (3) The stability of the mercury surface species formed on the AC in the H{sub 2}S-absence and HCl-presence system was similar to that of mercury chloride (HgClx) species. 25 refs., 12 figs., 1 tab.

  1. Investigation on mercury removal method from flue gas in the presence of sulfur dioxide.

    PubMed

    Ma, Yongpeng; Qu, Zan; Xu, Haomiao; Wang, Wenhua; Yan, Naiqiang

    2014-08-30

    A new integrated process was developed for the removal and reclamation of mercury from the flue gas in the presence of SO2, typically derived from nonferrous metal smelting. The new process contains a pre-desulfurization unit (Stage I) and a co-absorption unit (Stage II). In Stage I, 90% of the SO2 from flue gas can be efficiently absorbed by ferric sulfate and reclaimed sulfuric acid. Meanwhile, the proportion of Hg(2+) and Hg(0) in the flue gas can be redistributed in this stage. Then, over 95% of the Hg(0) and the residual SO2 can be removed simultaneously with a composite absorption solution from the flue gas in Stage II, which is much more efficient for the Hg(0) reclaiming than the traditional method. The composite absorption solution in Stage II, which is composed of 0.1g/L HgSO4, 1.0% H2O2 and H2SO4, could effectively remove and reclaim Hg(0) overcoming the negative effect of SO2 on Hg(0) absorption. Moreover, the concentrations of HgSO4 and H2O2 were adjusted with the changes in of the concentrations of Hg(0) and SO2 in the flue gas. It is a potential and promising technology for the mercury removal and reclaim from the flue gas in the presence of SO2. PMID:25072135

  2. Simultaneous removal of mercury, PCDD/F, and fine particles from flue gas.

    PubMed

    Korell, Jens; Paur, Hanns-R; Seifert, Helmut; Andersson, Sven

    2009-11-01

    A multifunctional scrubber (MFS) has been developed to reduce the complexity of flue gas cleaning plants. The MFS integrates an oxidizing scrubber equipped with a dioxin-absorbing tower packing material and a space charge electrostatic precipitator. All these processes have been previously developed at Forschungszentrum Karlsruhe. In the described multifunctional scrubber, mercury, sulfur dioxide, hydrogen chloride, polychlorinated dibenzo-p-dioxins (PCDD), polychlorinated dibenzofurans (PCDF), and submicrometer particles are removed simultaneously. A MFS pilot plant with a flue gas volume flow of 250 m(3)/h has been installed in a slipstream of a waste incineration pilot plant. Pilot scale testing was performed to measure mercury, particles, and PCDD/F in the raw and clean gas. After optimization of the process these three flue gas components were separated from the flue gas in the range 87-97%. PMID:19924961

  3. Evaluation of Crystalline Silicotitanate and Self-Assembled Monolayers on Mesoporous Support for Cesium and Mercury Removal from DWPF Recycle

    SciTech Connect

    Oji, L.N.

    1999-11-05

    The affinities for cesium and mercury ions contained in DWPF recycle simulants and Tank-22H waste have been evaluated using Crystalline Silicotitanate (CST) and Self-Assembled Monolayers on Mesoporous Support (SAMMS) ion-exchange materials, respectively. Results of the performance evaluations of CST on the uptake of cesium with simulants and actual DWPF recycle samples (Tank 22H) indicate that, in practice, this inorganic ion-exchange material can be used to remove radioactive cesium from the DWPF recycle. SAMMS material showed little or no affinity for mercury from highly alkaline DWPF waste. However, at near neutral conditions (DWPF simulant solution pH adjusted to 7), SAMMS was found to have a significant affinity for mercury. Conventional Duolite/256 ion exchange material showed an increase in affinity for mercury with increase in DWPF recycle simulant pH. Duolite/256 GT-73 also had a high batch distribution coefficient for mercury uptake from actual Tank 22H waste.

  4. Mercury contamination study for flight system safety

    NASA Technical Reports Server (NTRS)

    Gorzynski, C. S., Jr.; Maycock, J. N.

    1972-01-01

    The effects and prevention of possible mercury pollution from the failure of solar electric propulsion spacecraft using mercury propellant were studied from tankage loading of post launch trajector injection. During preflight operations and initial flight mode there is little danger of mercury pollution if proper safety precautions are taken. Any spillage on the loading, mating, transportation, or launch pad areas is obvious and can be removed by vacuum cleaning soil and chemical fixing. Mercury spilled on Cape Kennedy ground soil will be chemically complexed and retained by the sandstone subsoil. A cover layer of sand or gravel on spilled mercury which has settled to the bottom of a water body adjacent to the system operation will control and eliminate the formation of toxic organic mercurials. Mercury released into the earth's atmosphere through leakage of a fireball will be diffused to low concentration levels. However, gas phase reactions of mercury with ozone could cause a local ozone depletion and result in serious ecological hazards.

  5. A novel pre-oxidation method for elemental mercury removal utilizing a complex vaporized absorbent.

    PubMed

    Zhao, Yi; Hao, Runlong; Guo, Qing

    2014-09-15

    A novel semi-dry integrative method for elemental mercury (Hg(0)) removal has been proposed in this paper, in which Hg(0) was initially pre-oxidized by a vaporized liquid-phase complex absorbent (LCA) composed of a Fenton reagent, peracetic acid (CH3COOOH) and sodium chloride (NaCl), after which Hg(2+) was absorbed by the resultant Ca(OH)2. The experimental results indicated that CH3COOOH and NaCl were the best additives for Hg(0) oxidation. Among the influencing factors, the pH of the LCA and the adding rate of the LCA significantly affected the Hg(0) removal. The coexisting gases, SO2 and NO, were characterized as either increasing or inhibiting in the removal process, depending on their concentrations. Under optimal reaction conditions, the efficiency for the single removal of Hg(0) was 91%. Under identical conditions, the efficiencies of the simultaneous removal of SO2, NO and Hg(0) were 100%, 79.5% and 80.4%, respectively. Finally, the reaction mechanism for the simultaneous removal of SO2, NO and Hg(0) was proposed based on the characteristics of the removal products as determined by X-ray diffraction (XRD), atomic fluorescence spectrometry (AFS), the analysis of the electrode potentials, and through data from related research references. PMID:25146096

  6. Raw and Treated Rice Husks as Sorbents for Mercury Removal from Aqueous Solutions

    NASA Astrophysics Data System (ADS)

    Befani, Maria R.; Manariotis, Ioannis D.; Karapanagioti, Hrissi K.; Quintero, César E.

    2014-05-01

    Environmental pollution with heavy metals is a growing problem and the need for adequate and inexpensive techniques for removal is urgent. Sorption is an effective method for removing heavy metals from aqueous solutions. During rice milling, large quantities of rice husk waste are generated. This product is used in part as fuel in drying grain plants, which generates a second byproduct: rice husk ash. By this way, two types of relatively low-cost materials are obtained, which seem to be promising sorbents for the removal of heavy metals from aqueous systems. The aim of this study was to evaluate the ability of two groups of materials obtained from rice residues to remove mercury from aqueous solutions. The first group consisted of different size fractions of rice husk (RH): RH1 (>1.18 mm), RH2 (0.15 to 1.18 mm) and RH3 (<0.15 mm). The second group consisted of rice husk pyrolyzed at different temperatures and sizes to obtain the following biochars: RHA3 (>1.18 mm; 850ºC), RHA4 (0.15 to 1.18 mm; 850ºC), RHA300 (raw; 300ºC). The ash from rice husk pyrolyzed at 800ºC in oven of the grain drying plant (RHA800) was also evaluated. The surface area and pore volume were determined using nitrogen adsorption/desorption at liquid nitrogen temperature. The surface morphology of the materials was characterized by Scanning Electron Microscopy. The BET surface area varied between a minimum of 0.76 m2/g (RH2) and a maximum of 330 m2/g (RHA4). The range of the average pore diameter was between 46 Å (RHA4) to 266 Å (RH2). The pore size distribution analysis showed that the materials were mainly low porous or mesoporous except RHA4 that was microporous (53% of the pore volume for RHA4 is due to micropores). The effect of the initial solution pH on the mercury uptake was studied in the range of 2 to 6, using a contact time of 24 h and an initial concentration (Co) of 50 mg Hg(II)/L. The greatest mercury uptake occurred for pH values between 4 and 5. Four materials were selected

  7. Mercury

    MedlinePlus

    ... be found in: Batteries Chemistry labs Some disinfectants Folk remedies Red cinnabar mineral Organic mercury can be ... heart tracing Fluids through a vein (by IV) Medicine to treat symptoms The type of exposure will ...

  8. Use of sulfide-containing liquors for removing mercury from flue gases

    DOEpatents

    Nolan, Paul S.; Downs, William; Bailey, Ralph T.; Vecci, Stanley J.

    2003-01-01

    A method and apparatus for reducing and removing mercury in industrial gases, such as a flue gas, produced by the combustion of fossil fuels, such as coal, adds sulfide ions to the flue gas as it passes through a scrubber. Ideally, the source of these sulfide ions may include at least one of: sulfidic waste water, kraft caustic liquor, kraft carbonate liquor, potassium sulfide, sodium sulfide, and thioacetamide. The sulfide ion source is introduced into the scrubbing liquor as an aqueous sulfide species. The scrubber may be either a wet or dry scrubber for flue gas desulfurization systems.

  9. Use of sulfide-containing liquors for removing mercury from flue gases

    DOEpatents

    Nolan, Paul S.; Downs, William; Bailey, Ralph T.; Vecci, Stanley J.

    2006-05-02

    A method and apparatus for reducing and removing mercury in industrial gases, such as a flue gas, produced by the combustion of fossil fuels, such as coal, adds sulfide ions to the flue gas as it passes through a scrubber. Ideally, the source of these sulfide ions may include at least one of: sulfidic waste water, kraft caustic liquor, kraft carbonate liquor, potassium sulfide, sodium sulfide, and thioacetamide. The sulfide ion source is introduced into the scrubbing liquor as an aqueous sulfide species. The scrubber may be either a wet or dry scrubber for flue gas desulfurization systems.

  10. Development of new sorbents to remove mercury and selenium from flue gas. Final report, September 1, 1993--August 31, 1994

    SciTech Connect

    Shiao, S.Y.

    1995-02-01

    Mercury (Hg) and selenium (Se) are two of the volatile trace metals in coal, which are often not captured by conventional gas clean up devices of coal-fired boilers. An alternative is to use sorbents to capture the volatile components of trace metals after coal combustion. In this project sorbent screening tests were performed in which ten sorbents were selected to remove metallic mercury in N{sub 2}. These sorbents included activated carbon, char prepared from Ohio No. 5 coal, molecular sieves, silica gel, aluminum oxide, hydrated lime, Wyoming bentonite, kaolin, and Amberite IR-120 (an ion-exchanger). The sorbents were selected based on published information and B&W`s experience on mercury removal. The promising sorbent was then selected and modified for detailed studies of removal of mercury and selenium compounds. The sorbents were tested in a bench-scale adsorption facility. A known amount of each sorbent was loaded in the column as a packed bed. A carrier gas was bubbled through the mercury and selenium compounds. The vaporized species were carried by the gas and went through the sorbent beds. The amount of mercury and selenium compounds captured by the sorbents was determined by atomic absorption. Results are discussed.

  11. Mercury

    NASA Astrophysics Data System (ADS)

    Taylor, G. J.; Scott, E. R. D.

    2003-12-01

    Mercury is an important part of the solar system puzzle, yet we know less about it than any other planet, except Pluto. Mercury is the smallest of the terrestrial planets (0.05 Earth masses) and the closest to the Sun. Its relatively high density (5.4 g cm -3) indicates that it has a large metallic core (˜3/4 of the planet's radius) compared to its silicate mantle and crust. The existence of a magnetic field implies that the metallic core is still partly molten. The surface is heavily cratered like the highlands of the Moon, but some areas are smooth and less cratered, possibly like the lunar maria (but not as dark). Its surface composition, as explained in the next section, appears to be low in FeO (only ˜3 wt.%), which implies that either its crust is anorthositic (Jeanloz et al., 1995) or its mantle is similarly low in FeO ( Robinson and Taylor, 2001).The proximity of Mercury to the Sun is particularly important. In one somewhat outmoded view of how the solar system formed, Mercury was assembled in the hottest region close to the Sun so that virtually all of the iron was in the metallic state, rather than oxidized to FeO (e.g., Lewis, 1972, 1974). If correct, Mercury ought to have relatively a low content of FeO. This hypothesis also predicts that Mercury should have high concentrations of refractory elements, such as calcium, aluminum, and thorium, and low concentrations of volatile elements, such as sodium and potassium, compared to the other terrestrial planets.Alternative hypotheses tell a much more nomadic and dramatic story of Mercury's birth. In one alternative view, wandering planetesimals that might have come from as far away as Mars or the inner asteroid belt accreted to form Mercury (Wetherill, 1994). This model predicts higher FeO and volatile elements than does the high-temperature model, and similar compositions among the terrestrial planets. The accretion process might have been accompanied by a monumental impact that stripped away much of the

  12. NOVEL PROCESS FOR REMOVAL AND RECOVERY OF VAPOR-PHASE MERCURY

    SciTech Connect

    Craig S. Turchi

    2000-09-29

    The goal of this project is to investigate the use of a regenerable sorbent for removing and recovering mercury from the flue gas of coal-fired power plants. The process is based on the sorption of mercury by noble metals and the thermal regeneration of the sorbent, recovering the desorbed mercury in a small volume for recycling or disposal. The project was carried out in two phases, covering five years. Phase I ran from September 1995 through September 1997 and involved development and testing of sorbent materials and field tests at a pilot coal-combustor. Phase II began in January 1998 and ended September 2000. Phase II culminated with pilot-scale testing at a coal-fired power plant. The use of regenerable sorbents holds the promise of capturing mercury in a small volume, suitable for either stable disposal or recycling. Unlike single-use injected sorbents such as activated carbon, there is no impact on the quality of the fly ash. During Phase II, tests were run with a 20-acfm pilot unit on coal-combustion flue gas at a 100 lb/hr pilot combustor and a utility boiler for four months and six months respectively. These studies, and subsequent laboratory comparisons, indicated that the sorbent capacity and life were detrimentally affected by the flue gas constituents. Sorbent capacity dropped by a factor of 20 to 35 during operations in flue gas versus air. Thus, a sorbent designed to last 24 hours between recycling lasted less than one hour. The effect resulted from an interaction between SO{sub 2} and either NO{sub 2} or HCl. When SO{sub 2} was combined with either of these two gases, total breakthrough was seen within one hour in flue gas. This behavior is similar to that reported by others with carbon adsorbents (Miller et al., 1998).

  13. Fine root mercury heterogeneity: metabolism of lower-order roots as an effective route for mercury removal.

    PubMed

    Wang, Jun-Jian; Guo, Ying-Ying; Guo, Da-Li; Yin, Sen-Lu; Kong, De-Liang; Liu, Yang-Sheng; Zeng, Hui

    2012-01-17

    Fine roots are critical components for plant mercury (Hg) uptake and removal, but the patterns of Hg distribution and turnover within the heterogeneous fine root components and their potential limiting factors are poorly understood. Based on root branching structure, we studied the total Hg (THg) and its cellular partitioning in fine roots in 6 Chinese subtropical trees species and the impacts of root morphological and stoichiometric traits on Hg partitioning. The THg concentration generally decreased with increasing root order, and was higher in cortex than in stele. This concentration significantly correlated with root length, diameter, specific root length, specific root area, and nitrogen concentration, whereas its cytosolic fraction (accounting for <10% of THg) correlated with root carbon and sulfur concentrations. The estimated Hg return flux from dead fine roots outweighed that from leaf litter, and ephemeral first-order roots that constituted 7.2-22.3% of total fine root biomass may have contributed most to this flux (39-71%, depending on tree species and environmental substrate). Our results highlight the high capacity of Hg stabilization and Hg return by lower-order roots and demonstrate that turnover of lower-order roots may be an effective strategy of detoxification in perennial tree species. PMID:22126585

  14. Fast and efficient removal of mercury from water samples using magnetic iron oxide nanoparticles modified with 2-mercaptobenzothiazole.

    PubMed

    Parham, H; Zargar, B; Shiralipour, R

    2012-02-29

    Mercury in the lowest levels of concentrations is dangerous for human health due to its bioaccumulation in body and toxicity. This investigation shows the effective removal of mercury (II) ions from contaminated surface waters by modified magnetic iron oxide nanoparticles (M-MIONPs) with 2-mercaptobenzothiazole as an efficient adsorbent. The proposed method is fast, simple, cheap, effective and safe for treatment of mercury polluted waters. Preparation of adsorbent is easy and removal time is short. Non-modified magnetic iron oxide nanoparticles (MIONPs) can adsorb up to 43.47% of 50 ngmL(-1) of Hg (II) ions from polluted water, but modified magnetic ironoxide nanoparticles (M-MIONPs) improved the efficiency up to 98.6% for the same concentration. The required time for complete removal of mercury ions was 4 min. Variation of pH and high electrolyte concentration (NaCl) of the solution do not have considerable effect on the mercury removal efficiency. Loading capacity of adsorbent for Hg ions is obtained to be 590 μgg(-1). PMID:22244341

  15. Screening of carbon-based sorbents for the removal of elemental mercury from simulated combustion flue gas

    SciTech Connect

    Young, B.C.; Musich, M.A.

    1995-12-31

    A fixed-bed reactor system with continuous Hg{sup 0} analysis capabilities was used to evaluate commercial carbon sorbents for the removal of elemental mercury from simulated flue gas. The objectives of the program were to compare the sorbent effectiveness under identical test conditions and to identify the effects of various flue gas components on elemental mercury sorption. Sorbents tested included steam-activated lignite, chemical-activated hardwood and bituminous coal, iodated steam-activated coconut shell, and sulfur-impregnated steam-activated bituminous coal. The iodated carbon was the most effective carbon, showing over 99% mercury removal according to EPA Method 101A. Data indicate that O{sub 2} (4 vol%) and SO{sub 2} (500 ppm) improved the mercury removal of the other carbons for tests at 150{degrees}C using 100 {mu}g/m{sup 3} Hg{sup 0}. Further, the presence of HCl (at 50 ppm) produced a magnitude increase in mercury removal for the steam-activated and sulfur-impregnated bituminous coal-based carbons.

  16. Screening of carbon-based sorbents for the removal of elemental mercury from simulated combustion flue gas

    SciTech Connect

    Young, B.C.; Musich, M.A.

    1995-12-31

    A fixed-bed reactor system with continuous Hg{sup 0} analysis capabilities was used to evaluate commercial carbon sorbents for the removal of elemental mercury from simulated flue gas. The objectives of the program were to compare the sorbent effectiveness under identical test conditions and to identify the effects of various flue gas components on elemental mercury sorption. Sorbents tested included steam-activated lignite, chemically activated hardwood, chemically activated bituminous coal, iodated steam-activated coconut shell, and sulfur-impregnated steam-activated bituminous coal. The iodated carbon was the most effective sorbent, showing over 99% mercury removal according to U.S. Environmental Protection Agency (EPA) Method 101A. Data indicate that adding O{sub 2} at 4 vol% reduced the effectiveness of the steam-activated lignite, chemically activated hardwood, and sulfur- impregnated steam-activated bituminous coal. Adding SO{sub 2} at 500 ppm improved the mercury removal of the sulfur-impregnated carbon. Further, the presence of HCl gas (at 50 ppm) produced an order of magnitude increase in mercury removal with the chemically activated and sulfur-impregnated bituminous coal-based carbons.

  17. Molecular-Dynamic Simulation of the Removal of Mercury from Graphene via Bombardment with Xenon Clusters

    NASA Astrophysics Data System (ADS)

    Galashev, A. E.

    2016-03-01

    The method of molecular dynamics has been used to study the removal of mercury from graphene by irradiating the target using a beam of Xe13 clusters with energies of 5-30 eV at angles of incidence of 0°, 45°, and 60°. The edges of the graphene sheet were hydrogenated. The complete removal of mercury from graphene was achieved at the angles of incidence of clusters equal to 45° and 60° with the energies of the beam E Xe ≥ 15 and 10 eV, respectively. A substantial part of the film was separated from graphene in the form of a droplet. The form of the distributions of stresses in the graphene sheet indicates the absence of enhancement of the stressed state in the course of the bombardment. The bombardment at the angle of incidence of clusters equal to 45° leads to the lowest roughness of graphene. As a result of the bombardments in the above ranges of energies and angles of cluster incidence, the hydrogenated edges of the graphene sheet did not suffer significant damage.

  18. TECHNOLOGY EVALUATION FOR WATERBORNE MERCURY REMOVAL AT THE Y12 NATIONAL SECURITY COMPLEX

    SciTech Connect

    He, Feng; Liang, Liyuan; Miller, Carrie L

    2011-01-01

    The Hg-contaminated processing water produced at Y-12 facility is discharged through the storm drain system, merged at Outfall 200, and then discharged to EFPC. Most of the baseflow mercury at Outfall 200 arises from a small number of short sections of storm drain. This report discusses the waterborne mercury treatment technologies to decrease mercury loading to the surface water of EFPC at Y-12 NSC. We reviewed current available waterborne Hg treatment technologies based on the specific conditions of Y-12 and identified two possible options: SnCl2 reduction coupled with air stripping (SnCl2/air stripping) and sorption. The ORNL 2008 and 2009 field studies suggested that SnCl2/air stripping has the capability to remove waterborne mercury with efficiency higher than 90% at Outfall 200. To achieve this goal, dechlorination (i.e., removing residual chlorine from water) using dechlorinating agents such as thiosulfate has to be performed before the reduction. It is unclear whether or not SnCl2/air stripping can reduce the mercury concentration from ~1000 ng/L to 51 ng/L at a full-scale operation. Therefore, a pilot test is a logical step before a full-scale design to answer questions such as Hg removal efficiency, selection of dechlorinating agents, and so on. The major advantages of the SnCl2/air stripping system are: (1) expected low cost at high flow (e.g., the flow at Outfall 200); and (2) production of minimum secondary waste. However, there are many environmental uncertainties associated with this technology by introducing tin to EFPC ecosystem, for example tin methylation causing abiotic Hg methylation, which should be addressed before a full-scale implementation. Mercury adsorption by granular activated carbon (GAC) is a proven technology for treating Hg at Y-12. The ONRL 2010 lab sorption studies suggest that thiol-based resins hold the promise to combine with GAC to form a more cost-effective treatment system. To achieve a treatment goal of 51 ng/L at Outfall

  19. Mercury removal from liquid effluents of the chlor-alkali industry by using the biomass Sargassum sp

    NASA Astrophysics Data System (ADS)

    Sobral, L. G. S.; de Barros Lima, R.; Leite, S. G. F.; Fernandes, A. L. V.

    2003-05-01

    In this work, the used biomass, for removing the mercuric species from the liquid effluents of the chlor-alkali plants was the macro-algae Sargassum sp. According to the results obtained, until this moment in time, it was possible to remove more than 99% of the ionic mercury with the advantage of not releasing me aqueous phase, that returns to the operation of brine production, the electrolyte of the electrolytic cells. In addition, it was verified that the biomass, once loaded with Mercury, can be reused in the biosorption step, after suffering an elution process.

  20. ENVIRONMENTAL TECHNOLOGY VERIFICATION: JOINT (NSF-EPA) VERIFICATION STATEMENT AND REPORT FOR THE REMOVAL OF MERCURY FROM DENTAL OFFICE WASTEWATER, DENTAL RECYCLING OF NORTH AMERICA (DRNA) MERCURY REMOVAL UNIT (MRU). - NSF 02/01/EPAWQPC-SWP

    EPA Science Inventory

    Verification testing of the Dental Recycling North America (DRNA) Mercury Removal Unit (MRU) was conducted over a seven week period, at a dental office in Michigan that had three operatory rooms and two hygiene rooms. The office operated four days per week and averaged approxiam...

  1. Simultaneous removal of PCDD/Fs, pentachlorophenol and mercury from contaminated soil.

    PubMed

    Hung, Pao-Chen; Chang, Shu-Hao; Ou-Yang, Chia-Chien; Chang, Moo-Been

    2016-02-01

    Pentachlorophenol (PCP), polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), and mercury were simultaneously removed from heavily contaminated soil using a continuous pilot-scale thermal system (CPTS). Operating the system at 700 °C with 22 min of retention time ensured that the residual contaminants in remediated soil are lower in concentration than the soil standards of Taiwan EPA require. Both PCP and PCDD/Fs are effectively destroyed during the treatment at high temperatures in the CPTS, but significant dechlorination of PCDD/Fs is also found, resulting in lower net destruction efficiencies of TCDD/F and PeCDD/F-congeners, compared with those of highly chlorinated Hx-, Hp- and OCDD/F congeners. Moreover, 2,3,7,8-TetraCDD is significantly formed if the retention time is not long enough for total destruction. Inadequate reaction time (or retention time) even may lead to a rise in TEQ-value due to incomplete dechlorination. Mercury is significantly desorbed from contaminated soil and discharged through the exhaust. For PCP and PCDD/Fs, the exhaust discharge percentages including both the remediated soil and the exhaust are <0.03% and 1.14% of the input, respectively, achieved with 700 °C and 33 min retention time. In contrast, some 97.8% of input mercury rate is desorbed and discharged via the exhaust, so that the latter should be carefully cleaned via efficient air pollution control devices, whereas this contribution focuses on the conditions required for reaching adequate soil cleaning. PMID:26347926

  2. Removing and recovering mercury from off-gases of thermal treatment processes

    SciTech Connect

    Roberts, D.L.; Broderick, T.E.; Stewart, R.M.

    1998-12-31

    ADA Technologies is developing a sorbent-based process that recovers mercury from off-gases produced during the thermal treatment of wastes found in the DOE complex. This process regenerates the sorbent on-line and recovers liquid, elemental mercury either for ultimate disposal if radioactivity is present or for commercial distillation and re-use if no radioactivity is present. Because of these attributes of the process, ADA Technologies has adopted the name Mercu-RE to describe its process. The authors have completed proof-of-principle field tests of this technology and are currently gathering engineering design data for scaling up the process. In both the field tests and laboratory tests, the process removes over 99% of the mercury from flue gases at temperatures up to 350 F and with up to 10% water vapor and 200 ppm HCl. The sorbent has always been regenerable, and the authors have tested up to 124 cycles of sorption and desorption with no loss of sorption capacity. Several physical configurations of the sorbent are possible including a packed bed of sorbent beads, sorbent incorporated on the fibers of a filter bag, and sorbent coating the inside walls of a monolith. For the off gas of thermal treatment units in the DOE environment, the best sorbent configuration is the packed bed. The authors have examined the durability of the sorbent by constantly exposing it to the regeneration temperature of 700 F and found that some sorbent formulations are unstable at these conditions while others are stable. In addition, a 50 ACFM skid is undergoing testing at MSE Technology Applications (Butte, MT) to determine the scale-up rules that will allow the process to be implemented on an operating thermal treatment unit.

  3. Electrospun metal oxide-TiO2 nanofibers for elemental mercury removal from flue gas.

    PubMed

    Yuan, Yuan; Zhao, Yongchun; Li, Hailong; Li, Yang; Gao, Xiang; Zheng, Chuguang; Zhang, Junying

    2012-08-15

    Nanofibers prepared by an electrospinning method were used to remove elemental mercury (Hg(0)) from simulated coal combustion flue gas. The nanofibers composed of different metal oxides (MO(x)) including CuO, In(2)O(3), V(2)O(5), WO(3) and Ag(2)O supported on TiO(2) have been characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy dispersing X-ray (EDX) and UV-vis spectra. The average diameters of these nanofibers were about 200nm. Compared to pure TiO(2), the UV-vis absorption intensity for MO(x)-TiO(2) increased significantly and the absorption bandwidth also expanded, especially for Ag(2)O-TiO(2) and V(2)O(5)-TiO(2). Hg(0) oxidation efficiencies over the MO(x)-TiO(2) nanofibers were tested under dark, visible light (vis) irradiation and UV irradiation, respectively. The results showed that WO(3) doped TiO(2) exhibited the highest Hg(0) removal efficiency of 100% under UV irradiation. Doping V(2)O(5) into TiO(2) enhanced Hg(0) removal efficiency greatly from 6% to 63% under visible light irradiation. Ag(2)O doped TiO(2) showed a steady Hg(0) removal efficiency of around 95% without any light due to the formation of silver amalgam. An extended experiment with 8 Hg(0) removal cycles showed that the MO(x)-TiO(2) nanofibers were stable for removing Hg(0) from flue gas. Factors responsible for the enhanced photocatalytic activities of the MO(x)-TiO(2) nanofibers were also discussed. PMID:22703732

  4. An optimized concept for flue gas cleaning downstream of MWCs using sodium tetrasulfide for mercury removal

    SciTech Connect

    Schuettenhelm, W.; Hartenstein, H.U.; Licata, A.

    1998-07-01

    In Germany and other central European countries, new emission standards for refuse incineration plants became effective in 1989/90. In recent years the operators of incinerating plants in Germany demanded higher removal emission efficiency than required by law in order to obtain local permits. In the course of the procurement process, complex flue gas cleaning systems were approved and built. As a result, the costs for air pollution control systems exceeded the costs of the refuse combustion system (stoker plus boiler) which has been reflected in the constantly climbing disposal costs. Not all of the increased disposal costs have been able to be passed along to the market. Economic pressure has led to a search for simple solutions and low-cost flue gas cleaning systems which correspond to the legal and contractual limits. A new processes was developed by L. and C. Steinmueller GmbH (Steinmueller) using sodium tetrasulfide (Na{sub 2}S{sub 4}) as a additive for the emission control of mercury. This paper will present an overview of the general application of this new technology in the waste-to-energy field. The efficiency of the reduction of mercury, and serviceability and the simple handling of this new technology will be shown by results of plants which are in operating. For a conclusion, an outlook is provided into future applications of this technology over the waste-to-energy field.

  5. Mercury

    NASA Technical Reports Server (NTRS)

    Gault, D. E.; Burns, J. A.; Cassen, P.; Strom, R. G.

    1977-01-01

    Prior to the flight of the Mariner 10 spacecraft, Mercury was the least investigated and most poorly known terrestrial planet (Kuiper 1970, Devine 1972). Observational difficulties caused by its proximity to the Sun as viewed from Earth caused the planet to remain a small, vague disk exhibiting little surface contrast or details, an object for which only three major facts were known: 1. its bulk density is similar to that of Venus and Earth, much greater than that of Mars and the Moon; 2. its surface reflects electromagnetic radiation at all wavelengths in the same manner as the Moon (taking into account differences in their solar distances); and 3. its rotation period is in 2/3 resonance with its orbital period. Images obtained during the flyby by Mariner 10 on 29 March 1974 (and the two subsequent flybys on 21 September 1974 and 16 March 1975) revealed Mercury's surface in detail equivalent to that available for the Moon during the early 1960's from Earth-based telescopic views. Additionally, however, information was obtained on the planet's mass and size, atmospheric composition and density, charged-particle environment, and infrared thermal radiation from the surface, and most significantly of all, the existence of a planetary magnetic field that is probably intrinsic to Mercury was established. In the following, this new information is summarized together with results from theoretical studies and ground-based observations. In the quantum jumps of knowledge that have been characteristic of "space-age" exploration, the previously obscure body of Mercury has suddenly come into sharp focus. It is very likely a differentiated body, probably contains a large Earth-like iron-rich core, and displays a surface remarkably similar to that of the Moon, which suggests a similar evolutionary history.

  6. Removal of trace mercury (II) from aqueous solution by in situ MnO(x) combined with poly-aluminum chloride.

    PubMed

    Lu, Xixin; Huangfu, Xiaoliu; Zhang, Xiang; Wang, Yaan; Ma, Jun

    2015-06-01

    Removal of trace mercury from aqueous solution by Mn (hydr)oxides formed in situ during coagulation with poly-aluminum chloride (PAC) (in situ MnO(x) combined with PAC) was investigated. The efficiency of trace mercury removal was evaluated under the experimental conditions of reaction time, Mn dosage, pH, and temperature. In addition, the ionic strength and the initial mercury concentration were examined to evaluate trace mercury removal for different water qualities. The results clearly demonstrated that in situ MnO(x) combined with PAC was effective for trace mercury removal from aqueous solution. A mercury removal ratio of 9.7 μg Hg/mg Mn was obtained at pH 3. Furthermore, at an initial mercury concentration of 30 μg/L and pH levels of both 3 and 5, a Mn dosage of 4 mg/L was able to lower the mercury concentration to meet the standards for drinking water quality at less than 1 μg/L. Analysis by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy suggests that the hydroxyls on the surface of Mn (hydr)oxides are the active sites for adsorption of trace mercury from aqueous solution. PMID:26042971

  7. THE EFFECT OF WATER (VAPOR-PHASE) AND CARBON ON ELEMENTAL MERCURY REMOVAL IN A FLOW REACTOR

    EPA Science Inventory

    The paper gives results of studying the effect of vapor-phase moisture on elemental mercury (Hgo) removal by activated carbon (AC) in a flow reactor. tests involved injecting AC into both a dry and a 4% moisture nitrogen (N2) /Hgo gas stream. A bituminous-coal-based AC (Calgon WP...

  8. Mercury contamination extraction

    DOEpatents

    Fuhrmann, Mark; Heiser, John; Kalb, Paul

    2009-09-15

    Mercury is removed from contaminated waste by firstly applying a sulfur reagent to the waste. Mercury in the waste is then permitted to migrate to the reagent and is stabilized in a mercury sulfide compound. The stable compound may then be removed from the waste which itself remains in situ following mercury removal therefrom.

  9. AN ELECTROCHEMICAL SYSTEM FOR REMOVING AND RECOVERING ELEMENTAL MERCURY FROM FLUE-STACK GASES

    EPA Science Inventory

    the impending EPA regulations on the control of mercury emissions from the flue stacks of coal-burning electric utilities has resulted in heightened interest in the development of advanced mercury control technologies such as sorbent injection and in-situ mercury oxidation. Altho...

  10. GASEOUS ELEMENTAL MERCURY IN THE MARINE BOUNDARY LAYER: EVIDENCE FOR RAPID REMOVAL IN ANTHROPOGENIC POLLUTION

    EPA Science Inventory

    In this study, gas-phase elemental mercury (Hg0) and related species (including inorganic reactive gaseous mercury (RGM) and particulate mercury (PHg)) were measured at Cheeka Peak Observatory (CPO), Washington State, in the marine boundary layer (MBL) during 2001-2002. Air of...

  11. Regenerative process for removal of mercury and other heavy metals from gases containing H.sub.2 and/or CO

    DOEpatents

    Jadhav, Raja A.

    2009-07-07

    A method for removal of mercury from a gaseous stream containing the mercury, hydrogen and/or CO, and hydrogen sulfide and/or carbonyl sulfide in which a dispersed Cu-containing sorbent is contacted with the gaseous stream at a temperature in the range of about 25.degree. C. to about 300.degree. C. until the sorbent is spent. The spent sorbent is contacted with a desorbing gaseous stream at a temperature equal to or higher than the temperature at which the mercury adsorption is carried out, producing a regenerated sorbent and an exhaust gas comprising released mercury. The released mercury in the exhaust gas is captured using a high-capacity sorbent, such as sulfur-impregnated activated carbon, at a temperature less than about 100.degree. C. The regenerated sorbent may then be used to capture additional mercury from the mercury-containing gaseous stream.

  12. Mercury Removal From Aqueous Solutions With Chitosan-Coated Magnetite Nanoparticles Optimized Using the Box-Behnken Design

    PubMed Central

    Rahbar, Nadereh; Jahangiri, Alireza; Boumi, Shahin; Khodayar, Mohammad Javad

    2014-01-01

    Background: Nowadays, removal of heavy metals from the environment is an important problem due to their toxicity. Objectives: In this study, a modified method was used to synthesize chitosan-coated magnetite nanoparticles (CCMN) to be used as a low cost and nontoxic adsorbent. CCMN was then employed to remove Hg2+ from water solutions. Materials and Methods: To remove the highest percentage of mercury ions, the Box-Behnken model of response surface methodology (RSM) was applied to simultaneously optimize all parameters affecting the adsorption process. Studied parameters of the process were pH (5-8), initial metal concentration (2-8 mg/L), and the amount of damped adsorbent (0.25-0.75 g). A second-order mathematical model was developed using regression analysis of experimental data obtained from 15 batch runs. Results: The optimal conditions predicted by the model were pH = 5, initial concentration of mercury ions = 6.2 mg/L, and the amount of damped adsorbent = 0.67 g. Confirmatory testing was performed and the maximum percentage of Hg2+ removed was found to be 99.91%. Kinetic studies of the adsorption process specified the efficiency of the pseudo second-order kinetic model. The adsorption isotherm was well-fitted to both the Langmuir and Freundlich models. Conclusions: CCMN as an excellent adsorbent could remove the mercury ions from water solutions at low and moderate concentrations, which is the usual amount found in environment. PMID:24872943

  13. Removal of elemental mercury by iodine-modified rice husk ash sorbents.

    PubMed

    Zhao, Pengfei; Guo, Xin; Zheng, Chuguang

    2010-01-01

    Iodine-modified calcium-based rice husk ash sorbents (I2/CaO/RHA) were synthesized and characterized by X-ray diffraction, X-ray fluorescence, and N2 isotherm adsorption/desorption. Adsorption experiments of vapor-phase elemental mercury (Hg0) were performed in a laboratory-scale fixed-bed reactor. I2/CaO/RHA performances on Hg0 adsorption were compared with those of modified Ca-based fly ash sorbents (I2/CaO/FA) and modified fly ash sorbents (I2/FA). Effects of oxidant loading, supports, pore size distribution, iodine impregnation modes, and temperature were investigated as well to understand the mechanism in capturing Hg0. The modified sorbents exhibited reasonable efficiency for Hg0 removal under simulated flue gas. The surface area, pore size distribution, and iodine impregnation modes of the sorbents did not produce a strong effect on Hg0 capture efficiency, while fair correlation was observed between Hg0 uptake capacity and iodine concentration. Therefore, the content of I2 impregnated on the sorbents was identified as the most important factor influencing the capacity of these sorbents for Hg0 uptake. Increasing temperature in the range of 80-140 degrees C caused a rise in Hg0 removal. A reaction mechanism that may explain the experimental results was presumed based on the characterizations and adsorption study. PMID:21235196

  14. MERCURY REMOVAL IN A NON-THERMAL, PLASMA-BASED MULTI-POLLUTANT CONTROL TECHNOLOGY FOR UTILITY BOILERS

    SciTech Connect

    Matthew B. Loomis

    2004-05-01

    This technical report describes the results from Task 1 of the Cooperative Agreement. Powerspan has installed, tested, and validated Hg SCEMS systems for measuring oxidized and elemental mercury at the pilot facility at R.E. Burger Generating Station in Shadyside, Ohio. When operating properly, these systems are capable of providing near real-time monitoring of inlet and outlet gas flow streams and are capable of extracting samples from different locations to characterize mercury removal at these different ECO process stages. This report discusses the final configuration of the Hg CEM systems and the operating protocols that increase the reliability of the HG SCEM measurements. Documentation on the testing done to verify the operating protocols is also provided. In addition the report provides details on the protocols developed and used for measurement of mercury in process liquid streams and in captured ash.

  15. Polymer pendant crown thioethers for removal of mercury from acidic wastes: synthesis, characterization and application

    SciTech Connect

    Reynolds, J G; Baumann, T F; Nelson, A J; Fox, G A

    2000-07-21

    Removal of mercury ions from industrial waste streams is a difficult and expensive problem requiring an efficient and selective extractant that is resistant to corrosive conditions. We have now developed an acid-resistant thiacrown polymer that has potential utility as a selective and cost-effective Hg{sup 2+} extractant. Copolymerization of a novel C-substituted thiacrown, N,N-(4-vinylbenzylmethyl)-2-aminomethyl-1,4,8,11,14-pentathiacycloheptadecane, with DVB (80% divinylbenzene) using a radical initiator generated a highly cross-linked polymer containing pendant thiacrowns. Mercury extraction capabilities of the polymer were tested in acidic media (pH range: 1.5 to 6.2) and the extraction of Hg{sup 2+} was determined to be 95% at a mixing time of 30 minutes. The thiacrown polymer was also determined to be selective for Hg{sup 2+}, even in the presence of high concentrations of competing ions such as Pb{sup 2+}, Cd{sup 2+}, Al{sup 3}, and Fe{sup 3+}. The bound Hg{sup 2+} ions can then be stripped from the polymer, allowing the polymer to be reused without significant loss of loading capacity. The binding of Hg{sup 2+} to the polymer has been examined by X-ray photoemission spectroscopy. The thiacrown appears unaffected by incorporation into the polymer and the Hg{sup 2+} appears to be bound to the polymer complex in a similar manner as Hg{sup 2+} is bound in monomeric thiacrowns containing five sulfur atoms.

  16. A three-stage system to remove mercury and dioxins in flue gases.

    PubMed

    Hylander, Lars D; Sollenberg, Hans; Westas, Håkan

    2003-03-20

    Mercury (Hg) from combustion of fossil fuels and waste is the dominant source of anthropogenic Hg emissions, globally amounting to more than 1500 t Hgyear(-1). These emissions must decrease substantially in order to counteract increasing environmental levels of Hg and reduce future toxic effects. Uppsala Energi AB, nowadays (May, 2002) Vattenfall Värme Uppsala AB, an energy company in Uppsala, Sweden, has invested in equipments for air and water pollution control of their three waste fired steam boilers. The flue gases are cleaned in three stages in series to meet the strict Swedish regulation. Electrostatic precipitators remove most dust in the first stage, wet scrubbers remove most water-soluble gases, and in the last stage a Filsorption unit removes most remaining impurities in particulate as well as gaseous form. The Filsorption process includes additives injection, sorption, and chemical reaction in a reactor and filtration with a fabric filter. The aim with this article is to evaluate the efficiency of the system to recover Hg in flue gases from boilers in routine operation. Flue gases, ashes, and water were sampled yearly for 21 years and analysed for Hg, dioxin, and other potential contaminants received at waste incineration. The results clearly demonstrate the decreasing use of Hg in society the last two decades as influenced by governmental policy regarding Hg. The results also indicate that the equipment efficiently removed Hg and dioxins from the flue gases to a final concentration of approximately 3.5 microg Hgm(-3) n and 0.01 ng dioxinsm(-3) n, corresponding to more than 97 and 99.9% reduction of Hg and dioxins, respectively, by cleaning in three stages. The electrostatic precipitators and Filsorption stages alone, with the scrubber in bypass, removed 90% of Hg in flue gases. Using the scrubber is motivated to remove acid components and additional Hg, but call for water separated after the condensers to be neutralised and cleaned, so that less than 5

  17. Mechanistic pathways of mercury removal from the organomercurial lyase active site

    PubMed Central

    Rodrigues, Viviana

    2015-01-01

    Bacterial populations present in Hg-rich environments have evolved biological mechanisms to detoxify methylmercury and other organometallic mercury compounds. The most common resistance mechanism relies on the H+-assisted cleavage of the Hg–C bond of methylmercury by the organomercurial lyase MerB. Although the initial reaction steps which lead to the loss of methane from methylmercury have already been studied experimentally and computationally, the reaction steps leading to the removal of Hg2+ from MerB and regeneration of the active site for a new round of catalysis have not yet been elucidated. In this paper, we have studied the final steps of the reaction catalyzed by MerB through quantum chemical computations at the combined MP2/CBS//B3PW91/6-31G(d) level of theory. While conceptually simple, these reaction steps occur in a complex potential energy surface where several distinct pathways are accessible and may operate concurrently. The only pathway which clearly emerges as forbidden in our analysis is the one arising from the sequential addition of two thiolates to the metal atom, due to the accumulation of negative charges in the active site. The addition of two thiols, in contrast, leads to two feasible mechanistic possibilities. The most straightforward pathway proceeds through proton transfer from the attacking thiol to Cys159 , leading to its removal from the mercury coordination sphere, followed by a slower attack of a second thiol, which removes Cys96. The other pathway involves Asp99 in an accessory role similar to the one observed earlier for the initial stages of the reaction and affords a lower activation enthalpy, around 14 kcal mol−1, determined solely by the cysteine removal step rather than by the thiol ligation step. Addition of one thiolate to the intermediates arising from either thiol attack occurs without a barrier and produces an intermediate bound to one active site cysteine and from which Hg(SCH3)2 may be removed only after

  18. High-efficient mercury removal from environmental water samples using di-thio grafted on magnetic mesoporous silica nanoparticles.

    PubMed

    Mehdinia, Ali; Akbari, Maryam; Baradaran Kayyal, Tohid; Azad, Mohammad

    2015-02-01

    In this work, magnetic di-thio functionalized mesoporous silica nanoparticles (DT-MCM-41) were prepared by grafting dithiocarbamate groups within the channels of magnetic mesoporous silica nanocomposites. The functionalized nanoparticles exhibited proper magnetic behavior. They were easily separated from the aqueous solution by applying an external magnetic field. The results indicated that the functionalized nanoparticles had a potential for high-efficient removal of Hg(2+) in environmental samples. The maximum adsorption capacity of the sorbent was 538.9 mg g(-1), and it took about 10 min to achieve the equilibrium adsorption. The resulted adsorption capacity was higher than similar works for adsorption of mercury. It can be due to the presence of di-thio and amine active groups in the structure of sorbent. The special properties of MCM-41 like large surface area and high porosity also provided a facile accessibility of the mercury ions into the ligand sites. The complete removal of mercury ions was attained with dithiocarbamate groups in a wide range of mercury concentrations. The recovery studies were also applied for the river water, seawater, and wastewater samples, and the values were over of 97 %. PMID:25172459

  19. Elimination of truncated recombinant protein expressed in Escherichia coli by removing cryptic translation initiation site.

    PubMed

    Jennings, Matthew J; Barrios, Adam F; Tan, Song

    2016-05-01

    Undesirable truncated recombinant protein products pose a special expression and purification challenge because such products often share similar chromatographic properties as the desired full length protein. We describe here our observation of both full length and a truncated form of a yeast protein (Gcn5) expressed in Escherichia coli, and the reduction or elimination of the truncated form by mutating a cryptic Shine-Dalgarno or START codon within the Gcn5 coding region. Unsuccessful attempts to engineer in a cryptic translation initiation site into other recombinant proteins suggest that cryptic Shine-Dalgarno or START codon sequences are necessary but not sufficient for cryptic translation in E. coli. PMID:26739786

  20. Mercury Removal, Methylmercury Formation, and Sulfate-Reducing Bacteria Profiles in Wetland Mesocosms Containing Gypsum-Amended Sediments and Scirpus californicus

    SciTech Connect

    King, J.K.

    2001-03-02

    A pilot-scale model was constructed to determine if a wetland treatment system (WTS) could effectively remove low-level mercury from an outfall located at the Department of Energy's Savannah River Site.

  1. Removal of Toxic Mercury from Petroleum Oil by Newly Synthesized Molecularly-Imprinted Polymer

    PubMed Central

    Khairi, Nor Ain Shahera; Yusof, Nor Azah; Abdullah, Abdul Halim; Mohammad, Faruq

    2015-01-01

    In recent years, molecularly-imprinted polymers (MIPs) have attracted the attention of several researchers due to their capability for molecular recognition, easiness of preparation, stability and cost-effective production. By taking advantage of these facts, Hg(II) imprinted and non-imprinted copolymers were prepared by polymerizing mercury nitrate stock solution (or without it) with methacrylic acid (MAA), 2-hydroxyl ethyl methacrylate (HEMA), methanol and ethylene glycol dimethacrylate (EGDMA) as the monomer, co-monomer solvent (porogen) and cross-linker, respectively. Thus, the formed Hg(II) imprinted polymer was characterized by using Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), Brunauer, Emmett and Teller (BET) and thermal gravimetric analysis (TGA). The separation and preconcentration characteristics of Hg(II) imprinted polymer were investigated by solid phase extraction (SPE) procedures, and an optimal pH of 7 was investigated as ideal. The specific surface area of the Hg(II) imprinted polymer was found to be 19.45 m2/g with a size range from 100 to 140 µm in diameter. The maximum adsorption capacity was observed to be 1.11 mg/g of Hg(II) imprinted beads with 87.54% removal of Hg(II) ions within the first 5 min. The results of the study therefore confirm that the Hg(II) imprinted polymer can be used multiple times without significantly losing its adsorption capacity. PMID:26006226

  2. Removal of toxic mercury from petroleum oil by newly synthesized molecularly-imprinted polymer.

    PubMed

    Khairi, Nor Ain Shahera; Yusof, Nor Azah; Abdullah, Abdul Halim; Mohammad, Faruq

    2015-01-01

    In recent years, molecularly-imprinted polymers (MIPs) have attracted the attention of several researchers due to their capability for molecular recognition, easiness of preparation, stability and cost-effective production. By taking advantage of these facts, Hg(II) imprinted and non-imprinted copolymers were prepared by polymerizing mercury nitrate stock solution (or without it) with methacrylic acid (MAA), 2-hydroxyl ethyl methacrylate (HEMA), methanol and ethylene glycol dimethacrylate (EGDMA) as the monomer, co-monomer solvent (porogen) and cross-linker, respectively. Thus, the formed Hg(II) imprinted polymer was characterized by using Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM), Brunauer, Emmett and Teller (BET) and thermal gravimetric analysis (TGA). The separation and preconcentration characteristics of Hg(II) imprinted polymer were investigated by solid phase extraction (SPE) procedures, and an optimal pH of 7 was investigated as ideal. The specific surface area of the Hg(II) imprinted polymer was found to be 19.45 m2/g with a size range from 100 to 140 µm in diameter. The maximum adsorption capacity was observed to be 1.11 mg/g of Hg(II) imprinted beads with 87.54% removal of Hg(II) ions within the first 5 min. The results of the study therefore confirm that the Hg(II) imprinted polymer can be used multiple times without significantly losing its adsorption capacity. PMID:26006226

  3. A new page on the road book of inorganic mercury in fish body - tissue distribution and elimination following waterborne exposure and post-exposure periods.

    PubMed

    Pereira, Patrícia; Raimundo, Joana; Barata, Marisa; Araújo, Olinda; Pousão-Ferreira, Pedro; Canário, João; Almeida, Armando; Pacheco, Mário

    2015-03-01

    There are several aspects of inorganic mercury (iHg) toxicokinetics in fish that remain undeveloped despite its environmental ubiquity, bioaccumulation capacity and toxicity. Thus, this study presents new information on the uptake, distribution and accumulation of iHg following water contamination by adopting a novel set of body compartments (gills, eye wall, lens, blood, liver, brain and bile) of the white sea bream (Diplodus sargus) over 14 days of exposure. Realistic levels of iHg in water (2 μg L(-1)) were adopted in order to engender reliable conclusions in the assessment of fish health. A depuration phase of 28 days was also considered with the purpose of clarifying iHg elimination. It was found that iHg was accumulated faster in the gills (within 1 day), which also had the highest accumulated levels among all the target tissues/organs. Moreover, iHg increased gradually with exposure time in all the tissues/organs, except for the lens that showed relatively unaltered levels throughout the experiment. After 14 days of exposure, lower values of Hg were recorded in the brain/eye wall compared to the liver, which is probably related with the presence of blood-organ protection barriers, which limit iHg influx. iHg reached the brain earlier than the eye wall (3 and 7 days, respectively) and, hence, higher accumulated levels were recorded in the former. A depuration period of 28 days did not allow the total elimination of iHg in any of the tissues/organs. Despite this, iHg was substantially eliminated in the gills, blood and liver, whereas the brain and eye wall were not able to eliminate iHg within this timeframe. The brain and eye wall are more "refractory" structures with regard to iHg elimination, and this could represent a risk for wild fish populations. PMID:25677695

  4. ENVIRONMENTAL TECHNOLOGY VERIFICATION REPORT REMOVAL OF MERCURY FROM DENTAL OFFICE WASTEWATER

    EPA Science Inventory

    Verification testing of the DRNA Mercury Recovery Unit (MRU) was conducted during a seven-week period, at a dental office in Michigan that had three operatory rooms and two hygiene rooms. The office operated four days per week and averaged approximately eight (8) mercury amalgam ...

  5. High frequency ultrasound as a selective advanced oxidation process to remove penicillinic antibiotics and eliminate its antimicrobial activity from water.

    PubMed

    Serna-Galvis, Efraim A; Silva-Agredo, Javier; Giraldo-Aguirre, Ana L; Flórez-Acosta, Oscar A; Torres-Palma, Ricardo A

    2016-07-01

    This work studies the sonochemical degradation of a penicillinic antibiotic (oxacillin) in simulated pharmaceutical wastewater. High frequency ultrasound was applied to water containing the antibiotic combined with mannitol or calcium carbonate. In the presence of additives, oxacillin was efficiently removed through sonochemical action. For comparative purposes, the photo-Fenton, TiO2 photocatalysis and electrochemical oxidation processes were also tested. Therefore, the evolution of the antibiotic and its associated antimicrobial activity (AA) were monitored. A high inhibition was found for the other three oxidation processes in the elimination of the antimicrobial activity caused by the additives; while for the ultrasonic treatment, a negligible effect was observed. The sonochemical process was able to completely degrade the antibiotic, generating solutions without AA. In fact, the elimination of antimicrobial activity showed an excellent performance adjusted to exponential kinetic-type decay. The main sonogenerated organic by-products were determined by means of HPLC-MS. Four intermediaries were identified and they have modified the penicillinic structure, which is the moiety responsible for the antimicrobial activity. Additionally, the possible oxacillin sonodegradation mechanism was proposed based on the evolution of the by-products and their chemical structure. Furthermore, the high-frequency ultrasound action over 120 min readily removed oxacillin and eliminated its antimicrobial activity. However, the pollutant was not mineralized even after a long period of ultrasonic irradiation (360 min). Interestingly, the previously sonicated water containing oxacillin and both additives was completely mineralized using non-adapted microorganisms from a municipal wastewater treatment plant. These results show that the sonochemical treatment transformed the initial pollutant into substances that are biotreatable with a typical aerobic biological system. PMID:26964950

  6. Removal and recovery of mercury(II) from hazardous wastes using 1-(2-thiazolylazo)-2-naphthol functionalized activated carbon as solid phase extractant.

    PubMed

    Starvin, A M; Rao, T Prasada

    2004-09-10

    As a part of removal of toxic heavy metals from hazardous wastes, solid phase extraction (SPE) of mercury(II) at trace and ultra trace levels was studied using 1-(2-thiazolylazo)-2-naphthol (TAN) functionalized activated carbon (AC). The SPE material removes traces of mercury(II) quantitatively in the pH range 6.0 +/- 0.2. Other parameters that influence quantitative recovery of mercury(II), viz. percent concentration of TAN in AC, amount of TAN-AC, preconcentration time and volume of aqueous phase were varied and optimized. The possible means of removal of Hg(II) from other metal ions that are likely to be present in the wastes of the chloroalkali industry is discussed. The potential of TAN-functionalized AC SPE material for decontaminating mercury from the brine sludge and cell house effluent of a chloralkali plant has been evaluated. PMID:15363516

  7. Mercury Removal with Activated Carbon in Coal-Fired Power Plants

    NASA Astrophysics Data System (ADS)

    Rapperport, J.; Sasmaz, E.; Wilcox, J.

    2010-12-01

    Coal is both the most abundant and the dirtiest combustible energy source on earth. In the United States, about half of the country’s electricity comes from coal combustion and the industry is rapidly expanding all over the world. Among many of coal’s flaws, its combustion annually produces roughly 50 tones in the U.S. and 5000 tons worldwide of mercury, a carcinogen and highly toxic pollutant. Certain sorbents and processes are used to try to limit the amount of mercury that reaches the atmosphere, a key aspect of reducing the energy source’s harmful environmental impact. This experiment’s goal is to discover what process occurs on a sorbent surface during mercury’s capture while also determining sorbent effectiveness. Bench-scale experiments are difficult to carry out since the focus of the experiment is to simulate mercury capture in a power plant flue gas stream, where mercury is in its elemental form. The process involves injecting air, elemental mercury and other components to simulate a coal exhaust environment, and then running the stream through a packed-bed reactor with an in-tact sorbent. While carrying out the reactor tests, the gas-phase is monitored for changes in mercury oxidation and following these gas-phase studies, the mercury-laden sorbent is analyzed using x-ray photoelectron spectroscopy. Conclusions that can be drawn thus far are that brominated activated carbon shows very high mercury capture and that mercury is found in its oxidized form on the surface of the sorbent. The speciation, or conclusions drawn on the process and bonding sites on the surface, cannot be determined at this point simply using the current spectroscopic analysis.

  8. Synthesis and characterization of LTA nanozeolite using barley husk silica: Mercury removal from standard and real solutions

    SciTech Connect

    Azizi, Seyed Naser; Dehnavi, Ahmad Roozbehani; Joorabdoozha, Amir

    2013-05-15

    Highlights: ► Silica extraction from barley husk with high purity for the synthesis of A nanozeolite. ► Free template A nanozeolite synthesized via new source of silica at low temperature. ► Optimization of SiO{sub 2}/Al{sub 2}O{sub 3}, Na{sub 2}O/SiO{sub 2} ratios, temperature and time of the synthesis. ► Utilizing of synthesized A nanozeolite for mercury removal from aqueous solutions. ► Mercury removal at optimized pH, contact time and adsorbent dose from real solution. - Abstract: In this study, synthesized Lined Type A (LTA) nanozeolite from barley husk silica (BHS) was used for mercury removal from standard and real aqueous solutions. The BHS in amorphous phase with 80% purity was extracted from barley husk ash (BHA), and used effectively as a new source of silica for the synthesis of NaA nanozeolite. The NaA nanocrystal in pure phase has been synthesized at low temperature, without adding any organic additives. The effects of heating time, reaction temperature, SiO{sub 2}/Al{sub 2}O{sub 3}, and Na{sub 2}O/SiO{sub 2} mole ratios on the crystallization of NaA nanozeolite were studied. The adsorption capacity of mercury (II) was studied as a function of pH, contact time, and amount of adsorbent. The crystallization of NaA nanozeolite from BHS was characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), Brunauer–Emmett–Teller (BET), and FTIR techniques. Moreover, concentration of Hg{sup 2+} ions in the aqueous solutions was analyzed by hydride generation atomic absorption spectroscopy method (HG-AAS). The standard and real samples analysis showed that NaA nanozeolite is capable of Hg{sup 2+} ions removal from the aqueous solutions. Efficiency of mercury (II) adsorption from real solutions onto the nano-sized NaA zeolite was 98%.

  9. Removing Obstacles To Eliminating Racial And Ethnic Disparities In Behavioral Health Care.

    PubMed

    Alegría, Margarita; Alvarez, Kiara; Ishikawa, Rachel Zack; DiMarzio, Karissa; McPeck, Samantha

    2016-06-01

    Despite decades of research, racial and ethnic disparities in behavioral health care persist. The Affordable Care Act expanded access to behavioral health care, but many reform initiatives fail to consider research about racial/ethnic minorities. Mistaken assumptions that underlie the expansion of behavioral health care run the risk of replicating existing service disparities. Based on a review of relevant literature and numerous observational and field studies with minority populations, we identified the following three mistaken assumptions: Improvement in health care access alone will reduce disparities, current service planning addresses minority patients' preferences, and evidence-based interventions are readily available for diverse populations. We propose tailoring the provision of care to remove obstacles that minority patients face in accessing treatment, promoting innovative services that respond to patients' needs and preferences, and allowing flexibility in evidence-based practice and the expansion of the behavioral health workforce. These proposals should help meet the health care needs of a growing racial/ethnic minority population. PMID:27269014

  10. Development of Nano-Sulfide Sorbent for Efficient Removal of Elemental Mercury from Coal Combustion Fuel Gas.

    PubMed

    Li, Hailong; Zhu, Lei; Wang, Jun; Li, Liqing; Shih, Kaimin

    2016-09-01

    The surface area of zinc sulfide (ZnS) was successfully enlarged using nanostructure particles synthesized by a liquid-phase precipitation method. The ZnS with the highest surface area (named Nano-ZnS) of 196.1 m(2)·g(-1) was then used to remove gas-phase elemental mercury (Hg(0)) from simulated coal combustion fuel gas at relatively high temperatures (140 to 260 °C). The Nano-ZnS exhibited far greater Hg(0) adsorption capacity than the conventional bulk ZnS sorbent due to the abundance of surface sulfur sites, which have a high binding affinity for Hg(0). Hg(0) was first physically adsorbed on the sorbent surface and then reacted with the adjacent surface sulfur to form the most stable mercury compound, HgS, which was confirmed by X-ray photoelectron spectroscopy analysis and a temperature-programmed desorption test. At the optimal temperature of 180 °C, the equilibrium Hg(0) adsorption capacity of the Nano-ZnS (inlet Hg(0) concentration of 65.0 μg·m(-3)) was greater than 497.84 μg·g(-1). Compared with several commercial activated carbons used exclusively for gas-phase mercury removal, the Nano-ZnS was superior in both Hg(0) adsorption capacity and adsorption rate. With this excellent Hg(0) removal performance, noncarbon Nano-ZnS may prove to be an advantageous alternative to activated carbon for Hg(0) removal in power plants equipped with particulate matter control devices, while also offering a means of reusing fly ash as a valuable resource, for example as a concrete additive. PMID:27508312

  11. Modified Mesoporous Silica (SBA–15) with Trithiane as a new effective adsorbent for mercury ions removal from aqueous environment

    PubMed Central

    2014-01-01

    Background Removal of mercury from aqueous environment has been highly regarded in recent years and different methods have been tested for this purpose. One of the most effective ways for mercury ions (Hg+2) removal is the use of modified nano porous compounds. Hence, in this work a new physical modification of mesoporous silica (SBA-15) with 1, 3, 5 (Trithiane) as modifier ligand and its application for the removal of Hg+2 from aqueous environment has been investigated. SBA-15 and Trithiane were synthesized and the presence of ligand in the silica framework was demonstrated by FTIR spectrum. The amounts of Hg+2 in the samples were determined by cold vapor generation high resolution continuum source atomic absorption spectroscopy. Also, the effects of pH, stirring time and weight of modified SBA-15 as three major parameters for effective adsorption of Hg+2 were studied. Results The important parameter for the modification of the adsorbent was Modification ratio between ligand and adsorbent in solution which was 1.5. The results showed that the best Hg+2 removal condition was achieved at pH = 5.0, stirring time 15 min and 15.0 mg of modified adsorbent. Moreover, the maximum percentage removal of Hg+2 and the capacity of adsorbent were 85% and 10.6 mg of Hg+2/g modified SBA-15, respectively. Conclusions To sum up, the present investigation introduced a new modified nano porous compound as an efficient adsorbent for removal of Hg+2 from aqueous environment. PMID:25097760

  12. Preliminary results of pre-combustion removal of mercury, arsenic, and selenium from coal by dry magnetic separation

    SciTech Connect

    Oder, R.R.; Jamison, R.E.; Brandner, E.D.

    1999-07-01

    The authors report the results of preliminary measurements of pre-combustion separation of major metal oxides and trace elements from coal by dry magnetic separation. The measurements have been made as part of ETCi's development of MagMill{trademark} technology for removing mineral matter from coal at the pulverizer at the front end of a coal fired power plant. The technology is specific to separation of mercury, arsenic, and selenium because of their associations with iron pyrites in coal. Measurements were made on a suite of five Eastern US and five Illinois Basin bituminous rank coals prepared at 8 Mesh topsize and processed as 8 Mesh by zero fractions through a dry Para Trap Magnetic Separator. Measurements of major metals and trace elements were made on the feed coal, the magnetic refuse fraction and the magnetic clean coal product. The range of weight recoveries measured for 13 of the trace elements for the suite of coals indicates a significant potential for pre-combustion removal of trace elements and especially for mercury, selenium, and arsenic by dry magnetic methods. While these three elements are important because they are considered hazardous air pollutant precursors, pre-combustion removal of arsenic is especially important because of its role in poisoning catalysts used in emerging SO{sub x} and NO{sub x} control technologies.

  13. Mercury (II) removal by resistant bacterial isolates and mercuric (II) reductase activity in a new strain of Pseudomonas sp. B50A.

    PubMed

    Giovanella, Patricia; Cabral, Lucélia; Bento, Fátima Menezes; Gianello, Clesio; Camargo, Flávio Anastácio Oliveira

    2016-01-25

    This study aimed to isolate mercury resistant bacteria, determine the minimum inhibitory concentration for Hg, estimate mercury removal by selected isolates, explore the mer genes, and detect and characterize the activity of the enzyme mercuric (II) reductase produced by a new strain of Pseudomonas sp. B50A. The Hg removal capacity of the isolates was determined by incubating the isolates in Luria Bertani broth and the remaining mercury quantified by atomic absorption spectrophotometry. A PCR reaction was carried out to detect the merA gene and the mercury (II) reductase activity was determined in a spectrophotometer at 340 nm. Eight Gram-negative bacterial isolates were resistant to high mercury concentrations and capable of removing mercury, and of these, five were positive for the gene merA. The isolate Pseudomonas sp. B50A removed 86% of the mercury present in the culture medium and was chosen for further analysis of its enzyme activity. Mercuric (II) reductase activity was detected in the crude extract of this strain. This enzyme showed optimal activity at pH 8 and at temperatures between 37 °C and 45 °C. The ions NH4(+), Ba(2+), Sn(2+), Ni(2+) and Cd(2+) neither inhibited nor stimulated the enzyme activity but it decreased in the presence of the ions Ca(2+), Cu(+) and K(+). The isolate and the enzyme detected were effective in reducing Hg(II) to Hg(0), showing the potential to develop bioremediation technologies and processes to clean-up the environment and waste contaminated with mercury. PMID:26051077

  14. Effects of HCl and SO{sub 2} concentration on mercury removal by activated carbon sorbents in coal-derived flue gas

    SciTech Connect

    Ryota Ochiai; M. Azhar Uddin; Eiji Sasaoka; Shengji Wu

    2009-09-15

    The effect of the presence of HCl and SO{sub 2} in the simulated coal combustion flue gas on the Hg{sup 0} removal by a commercial activated carbon (coconut shell AC) was investigated in a laboratory-scale fixed-bed reactor in a temperature range of 80-200{sup o}C. The characteristics (thermal stability) of the mercury species formed on the sorbents under various adsorption conditions were investigated by the temperature-programmed decomposition desorption (TPDD) technique. It was found that the presence of HCl and SO{sub 2} in the flue gas affected the mercury removal efficiency of the sorbents as well as the characteristics of the mercury adsorption species. The mercury removal rate of AC increased with the HCl concentration in the flue gas. In the presence of HCl and the absence of SO{sub 2} during Hg{sup 0} adsorption by AC, a single Hg{sup 0} desorption peak at around 300{sup o}C was observed in the TPDD spectra and intensity of this peak increased with the HCl concentration during mercury adsorption. The peak at around 300{sup o}C may be derived from the decomposition and desorption of mercury chloride species. The presence of SO{sub 2} during mercury adsorption had an adverse effect on the mercury removal by AC in the presence of HCl. In the presence of both HCl and SO{sub 2} during Hg{sup 0} adsorption by AC, the major TPDD peak temperatures changed drastically depending upon the concentration of HCl and SO{sub 2} in flue gas during Hg{sup 0} adsorption. 16 refs., 7 figs.

  15. Electronic structure calculations of mercury mobilization from mineral phases and photocatalytic removal from water and the atmosphere.

    PubMed

    Da Pieve, Fabiana; Stankowski, Martin; Hogan, Conor

    2014-09-15

    Mercury is a hazardous environmental pollutant mobilized from natural sources, and anthropogenically contaminated and disturbed areas. Current methods to assess mobility and environmental impact are mainly based on field measurements, soil monitoring, and kinetic modelling. In order to understand in detail the extent to which different mineral sources can give rise to mercury release it is necessary to investigate the complexity at the microscopic level and the possible degradation/dissolution processes. In this work, we investigated the potential for mobilization of mercury structurally trapped in three relevant minerals occurring in hot spring environments and mining areas, namely, cinnabar (α-HgS), corderoite (α-Hg3S2Cl2), and mercuric chloride (HgCl2). Quantum chemical methods based on density functional theory as well as more sophisticated approaches are used to assess the possibility of a) direct photoreduction and formation of elemental Hg at the surface of the minerals, providing a path for ready release in the environment; and b) reductive dissolution of the minerals in the presence of solutions containing halogens. Furthermore, we study the use of TiO2 as a potential photocatalyst for decontamination of polluted waters (mainly Hg(2+)-containing species) and air (atmospheric Hg(0)). Our results partially explain the observed pathways of Hg mobilization from relevant minerals and the microscopic mechanisms behind photocatalytic removal of Hg-based pollutants. Possible sources of disagreement with observations are discussed and further improvements to our approach are suggested. PMID:24982025

  16. Engineering and characterization of mesoporous silica-coated magnetic particles for mercury removal from industrial effluents

    NASA Astrophysics Data System (ADS)

    Dong, Jie; Xu, Zhenghe; Wang, Feng

    2008-03-01

    Mesoporous silica coatings were synthesized on dense liquid silica-coated magnetite particles using cetyl-trimethyl-ammonium chloride (CTAC) as molecular templates, followed by sol-gel process. A specific surface area of the synthesized particles as high as 150 m 2/g was obtained. After functionalization with mercapto-propyl-trimethoxy-silane (MPTS) through silanation reaction, the particles exhibited high affinity of mercury in aqueous solutions. Atomic force microscopy (AFM), zeta potential measurement, thermal gravimetric analysis (TGA), analytical transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and atomic absorption spectroscopy (AAS) were used to characterize the synthesis processes, surface functionalization, and mercury adsorption on the synthesized magnetite particles. The loading capacity of the particles for mercury was determined to be as high as 14 mg/g at pH 2. A unique feature of strong magnetism of the synthesized nanocomposite particles makes the subsequent separation of the magnetic sorbents from complex multiphase suspensions convenient and effective.

  17. Integrated Removal of NOx with Carbon Monoxide as Reductant, and Capture of Mercury in a Low Temperature Selective Catalytic and Adsorptive Reactor

    SciTech Connect

    Neville Pinto; Panagiotis Smirniotis; Stephen Thiel

    2010-08-31

    Coal will likely continue to be a dominant component of power generation in the foreseeable future. This project addresses the issue of environmental compliance for two important pollutants: NO{sub x} and mercury. Integration of emission control units is in principle possible through a Low Temperature Selective Catalytic and Adsorptive Reactor (LTSCAR) in which NO{sub x} removal is achieved in a traditional SCR mode but at low temperature, and, uniquely, using carbon monoxide as a reductant. The capture of mercury is integrated into the same process unit. Such an arrangement would reduce mercury removal costs significantly, and provide improved control for the ultimate disposal of mercury. The work completed in this project demonstrates that the use of CO as a reductant in LTSCR is technically feasible using supported manganese oxide catalysts, that the simultaneous warm-gas capture of elemental and oxidized mercury is technically feasible using both nanostructured chelating adsorbents and ceria-titania-based materials, and that integrated removal of mercury and NO{sub x} is technically feasible using ceria-titania-based materials.

  18. MERCURY REMOVAL IN A NON-THERMAL, PLASMA-BASED MULTI-POLLUTANT CONTROL TECHNOLOGY FOR UTILITY BOILERS

    SciTech Connect

    Christopher R. McLaron

    2004-12-01

    Powerspan has conducted pilot scale testing of a multi-pollutant control technology at FirstEnergy's Burger Power Plant under a cooperative agreement with the U.S. Department of Energy. The technology, Electro-Catalytic Oxidation (ECO), simultaneously removes sulfur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), fine particulate matter (PM{sub 2.5}) and mercury (Hg) from the flue gas of coal-fired power plants. Powerspan's ECO{reg_sign} pilot test program focused on optimization of Hg removal in a 1-MWe slipstream pilot while maintaining greater than 90% removal of NO{sub x} and 98% removal of SO{sub 2}. This Final Technical Report discusses pilot operations, installation and maintenance of the Hg SCEMS instrumentation, and performance results including component and overall removal efficiencies of SO{sub 2}, NO{sub x}, PM and Hg from the flue gas and removal of captured Hg from the co-product fertilizer stream.

  19. "Wave" signal-smoothing and mercury-removing device for laser ablation quadrupole and multiple collector ICPMS analysis: application to lead isotope analysis.

    PubMed

    Hu, Zhaochu; Zhang, Wen; Liu, Yongsheng; Gao, Shan; Li, Ming; Zong, Keqing; Chen, Haihong; Hu, Shenghong

    2015-01-20

    A novel "wave" signal-smoothing and mercury-removing device has been developed for laser ablation quadrupole and multiple collector ICPMS analysis. With the wave stabilizer that has been developed, the signal stability was improved by a factor of 6.6-10 and no oscillation of the signal intensity was observed at a repetition rate of 1 Hz. Another advantage of the wave stabilizer is that the signal decay time is similar to that without the signal-smoothing device (increased by only 1-2 s for a signal decay of approximately 4 orders of magnitude). Most of the normalized elemental signals (relative to those without the stabilizer) lie within the range of 0.95-1.0 with the wave stabilizer. Thus, the wave stabilizer device does not significantly affect the aerosol transport efficiency. These findings indicate that this device is well-suited for routine optimization of ICPMS, as well as low repetition rate laser ablation analysis, which provides smaller elemental fractionation and better spatial resolution. With the wave signal-smoothing and mercury-removing device, the mercury gas background is reduced by 1 order of magnitude. More importantly, the (202)Hg signal intensity produced in the sulfide standard MASS-1 by laser ablation is reduced from 256 to 0.7 mV by the use of the wave signal-smoothing and mercury-removing device. This result suggests that the mercury is almost completely removed from the sample aerosol particles produced by laser ablation with the operation of the wave mercury-removing device. The wave mercury-removing device that we have designed is very important for Pb isotope ratio and accessory mineral U-Pb dating analysis, where removal of the mercury from the background gas and sample aerosol particles is highly desired. The wave signal-smoothing and mercury-removing device was applied successfully to the determination of the (206)Pb/(204)Pb isotope ratio in samples with low Pb content and/or high Hg content. PMID:25511501

  20. Reaching Part Per Trillion Clean-Up Criteria for Mercury in Water

    SciTech Connect

    Klasson, K. T.; Kosny, K.; Drescher, S. R.; Southworth, G. R.; Hensley, J. F.

    2003-02-24

    In the last couple of years, emphasis on environmental mercury contamination and elimination of mercury use has increased. The U.S. Department of Energy has for many decades maintained a stockpile of elemental mercury for operations and, as a consequence of its routine use, spills have occurred. These historical spills have resulted in some contamination of water streams and soils. In this work we examine a newly developed technique for removal of mercury from contaminated groundwater. In this application the mercury concentration was approximately 2.3 parts per billion and the treatment criterion was 200 parts per trillion. Several forms of mercury species contributed to the contamination. The treatment technique developed for this water was to convert all forms of mercury, through a series of fast chemical reactions, to elemental mercury, which was air-stripped from the water. This paper presents preliminary laboratory work on the method.

  1. Got Mercury?

    NASA Technical Reports Server (NTRS)

    Meyers, Valerie E.; McCoy, J. Torin; Garcia, Hector D.; James, John T.

    2009-01-01

    Many of the operational and payload lighting units used in various spacecraft contain elemental mercury. If these devices were damaged on-orbit, elemental mercury could be released into the cabin. Although there are plans to replace operational units with alternate light sources, such as LEDs, that do not contain mercury, mercury-containing lamps efficiently produce high quality illumination and may never be completely replaced on orbit. Therefore, exposure to elemental mercury during spaceflight will remain possible and represents a toxicological hazard. Elemental mercury is a liquid metal that vaporizes slowly at room temperature. However, it may be completely vaporized at the elevated operating temperatures of lamps. Although liquid mercury is not readily absorbed through the skin or digestive tract, mercury vapors are efficiently absorbed through the respiratory tract. Therefore, the amount of mercury in the vapor form must be estimated. For mercury releases from lamps that are not being operated, we utilized a study conducted by the New Jersey Department of Environmental Quality to calculate the amount of mercury vapor expected to form over a 2-week period. For longer missions and for mercury releases occurring when lamps are operating, we conservatively assumed complete volatilization of the available mercury. Because current spacecraft environmental control systems are unable to remove mercury vapors, both short-term and long-term exposures to mercury vapors are possible. Acute exposure to high concentrations of mercury vapors can cause irritation of the respiratory tract and behavioral symptoms, such as irritability and hyperactivity. Chronic exposure can result in damage to the nervous system (tremors, memory loss, insomnia, etc.) and kidneys (proteinurea). Therefore, the JSC Toxicology Group recommends that stringent safety controls and verifications (vibrational testing, etc.) be applied to any hardware that contains elemental mercury that could yield

  2. Removal of inorganic mercury and methylmercury from surface waters following coagulation of dissolved organic matter with metal-based salts

    USGS Publications Warehouse

    Henneberry, Y.K.; Kraus, T.E.C.; Fleck, J.A.; Krabbenhoft, D.P.; Bachand, P.M.; Horwath, W.R.

    2011-01-01

    The presence of inorganic mercury (IHg) and methylmercury (MeHg) in surface waters is a health concern worldwide. This study assessed the removal potential use of metal-based coagulants as a means to remove both dissolved IHg and MeHg from natural waters and provides information regarding the importance of Hg associations with the dissolved organic matter (DOM) fraction and metal hydroxides. Previous research indicated coagulants were not effective at removing Hg from solution; however these studies used high concentrations of Hg and did not reflect naturally occurring concentrations of Hg. In this study, water collected from an agricultural drain in the Sacramento-San Joaquin Delta was filtered to isolate the dissolved organic matter (DOM) fraction. The DOM was then treated with a range of coagulant doses to determine the efficacy of removing all forms of Hg from solution. Three industrial-grade coagulants were tested: ferric chloride, ferric sulfate, and polyaluminum chloride. Coagulation removed up to 85% of DOM from solution. In the absence of DOM, all three coagulants released IHg into solution, however in the presence of DOM the coagulants removed up to 97% of IHg and 80% of MeHg. Results suggest that the removal of Hg is mediated by DOM-coagulant interactions. There was a preferential association of IHg with the more aromatic, higher molecular weight fraction of DOM but no such relationship was found for MeHg. This study offers new fundamental insights regarding large-scale removal of Hg at environmentally relevant regarding large-scale removal of Hg at environmentally relevant concentrations.

  3. Role of SO{sub 2} for elemental mercury removal from coal combustion flue gas by activated carbon

    SciTech Connect

    M. Azhar Uddin; Toru Yamada; Ryota Ochiai; Eiji Sasaoka

    2008-07-15

    In order to clarify the role of SO{sub 2} in the removal of mercury from coal combustion flue gas by activated carbon, the removal of Hg{sup 0} vapor from simulated coal combustion flue gas containing SO{sub 2} by a commercial activated carbon (AC) was studied. The Hg{sup 0} removal experiments were carried out in a conventional flow type packed bed reactor system with simulated flue gases having a composition of Hg{sup 0} (4.9 ppb), SO{sub 2} (0 or 500 ppm), CO{sub 2} (10%), H{sub 2}O (0 or 15%), O{sub 2} (0 or 5%), and N{sub 2} (balance gas) at a space velocity (SV) of 6.0 x 104 h{sup -1} in a temperature rang 60-100 {sup o}C. It was found that, for SO{sub 2} containing flue gas, the presence of both O{sub 2} and H{sub 2}O was necessary for the removal of Hg{sup 0} and the Hg{sup 0} removal was favored by lowering the reaction temperature in the order of 60 > 80 > 100{sup o}C. The presence of SO{sub 2} in the flue was essential for the removal of Hg{sup 0} by untreated activated carbon. The activated carbons pretreated with SO{sub 2} or H{sub 2}SO{sub 4} prior to the Hg{sup 0} removal also showed Hg{sup 0} removal activities even in the absence of SO{sub 2}; however, the presence of SO{sub 2} also suppressed the Hg{sup 0} removal of the SO{sub 2}-pretreated AC or H{sub 2}SO{sub 4} preadded AC. 19 refs., 11 figs.

  4. Methods and sorbents for utilizing a hot-side electrostatic precipitator for removal of mercury from combustion gases

    DOEpatents

    Nelson, Sidney

    2011-02-15

    Methods are provided for reducing emission of mercury from a gas stream by treating the gas with carbonaceous mercury sorbent particles to reduce the mercury content of the gas; collecting the carbonaceous mercury sorbent particles on collection plates of a hot-side ESP; periodically rapping the collection plates to release a substantial portion of the collected carbonaceous mercury sorbent particles into hoppers; and periodically emptying the hoppers, wherein such rapping and emptying are done at rates such that less than 70% of mercury adsorbed onto the mercury sorbent desorbs from the collected mercury sorbent into the gas stream.

  5. Process for low mercury coal

    DOEpatents

    Merriam, N.W.; Grimes, R.W.; Tweed, R.E.

    1995-04-04

    A process is described for producing low mercury coal during precombustion procedures by releasing mercury through discriminating mild heating that minimizes other burdensome constituents. Said mercury is recovered from the overhead gases by selective removal. 4 figures.

  6. Process for low mercury coal

    DOEpatents

    Merriam, Norman W.; Grimes, R. William; Tweed, Robert E.

    1995-01-01

    A process for producing low mercury coal during precombustion procedures by releasing mercury through discriminating mild heating that minimizes other burdensome constituents. Said mercury is recovered from the overhead gases by selective removal.

  7. Method for removal of phosgene from boron trichloride. [DOE patent application; mercury arc lamp

    DOEpatents

    Freund, S.M.

    1981-09-03

    Selective ultraviolet photolysis using an unfiltered mercury arc lamp has been used to substantially reduce the phosgene impurity in a mixture of boron trichloride and phosgene. Infrared spectrophotometric analysis of the sample before and after irradiation shows that it is possible to highly purify commercially available boron trichloride with this method.

  8. Fe3-xCuxO4 as highly active heterogeneous Fenton-like catalysts toward elemental mercury removal.

    PubMed

    Zhou, Changsong; Sun, Lushi; Zhang, Anchao; Wu, Xiaofeng; Ma, Chuan; Su, Sheng; Hu, Song; Xiang, Jun

    2015-04-01

    A series of novel spinel Fe3-xCuxO4 (0remove elemental mercury (Hg0) from the simulated flue gases. Inductively coupled plasma-Atomic emission spectrometry (ICP-AES), X-ray diffraction patterns (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET) surface area, and X-ray photoelectron spectrometer (XPS) were used to characterize the catalysts. The catalysts were confirmed the presence of the redox pairs Fesurf2+/Fesurf3+ and Cusurf+/Cusurf2+ on the surface of the cubic structure. The performance of heterogeneous Fenton-like reactions for Hg0 removal was evaluated in a lab-scale bubbling reactor at the solution temperature of 50°C. The systematic studies on the effects of different catalysts, H2O2 concentration and solution pH values on Hg0 removal efficiencies were performed. The recycling of the Fe3-xCuxO4 catalysts in Fenton-like solution is stable and Hg0 removal efficiency remain above 90% after 3 cycles. The active hydroxyl radical (OH) generated during heterogeneous Fenton-like reactions was confirmed through electron spin resonance (ESR) spin-trapping technique. The Hg0 removal mechanism has been discussed based on the experimental and analytical results. PMID:25655441

  9. Removal of elemental mercury from flue gas by thermally activated ammonium persulfate in a bubble column reactor.

    PubMed

    Liu, Yangxian; Wang, Qian

    2014-10-21

    In this article, a novel technique on removal of elemental mercury (Hg(0)) from flue gas by thermally activated ammonium persulfate ((NH4)(2)S(2)O(8)) has been developed for the first time. Some experiments were carried out in a bubble column reactor to evaluate the effects of process parameters on Hg(0) removal. The mechanism and kinetics of Hg(0) removal are also studied. The results show that the parameters, (NH4)(2)S(2)O(8) concentration, activation temperature and solution pH, have significant impacts on Hg(0) removal. The parameters, Hg(0), SO2 and NO concentration, only have small effects on Hg(0) removal. Hg(0) is removed by oxidations of (NH4)(2)S(2)O(8), sulfate and hydroxyl free radicals. When (NH4)(2)S(2)O(8) concentration is more than 0.1 mol/L and solution pH is lower than 9.71, Hg(0) removal by thermally activated (NH4)(2)S(2)O(8) meets a pseudo-first-order fast reaction with respect to Hg(0). However, when (NH4)(2)S(2)O(8) concentration is less than 0.1 mol/L or solution pH is higher than 9.71, the removal process meets a moderate speed reaction with respect to Hg(0). The above results indicate that this technique is a feasible method for emission control of Hg(0) from flue gas. PMID:25251199

  10. Thioether-Based Fluorescent Covalent Organic Framework for Selective Detection and Facile Removal of Mercury(II).

    PubMed

    Ding, San-Yuan; Dong, Ming; Wang, Ya-Wen; Chen, Yan-Tao; Wang, Huai-Zhen; Su, Cheng-Yong; Wang, Wei

    2016-03-01

    Heavy metal ions are highly toxic and widely spread as environmental pollutants. New strategies are being developed to simultaneously detect and remove these toxic ions. Herein, we take the intrinsic advantage of covalent organic frameworks (COFs) and develop fluorescent COFs for sensing applications. As a proof-of-concept, a thioether-functionalized COF material, COF-LZU8, was "bottom-up" integrated with multifunctionality for the selective detection and facile removal of mercury(II): the π-conjugated framework as the signal transducer, the evenly and densely distributed thioether groups as the Hg(2+) receptor, the regular pores facilitating the real-time detection and mass transfer, together with the robust COF structure for recycle use. The excellent sensing performance of COF-LZU8 was achieved in terms of high sensitivity, excellent selectivity, easy visibility, and real-time response. Meanwhile, the efficient removal of Hg(2+) from water and the recycling of COF-LZU8 offers the possibility for practical applications. In addition, X-ray photoelectron spectroscopy and solid-state NMR investigations verified the strong and selective interaction between Hg(2+) and the thioether groups of COF-LZU8. This research not only demonstrates the utilization of fluorescent COFs for both sensing and removal of metal ions but also highlights the facile construction of functionalized COFs for environmental applications. PMID:26878337

  11. Full scale calcium bromide injection with subsequent mercury oxidation and removal within wet flue gas desulphurization system: Experience at a 700 MW coal-fired power facility

    NASA Astrophysics Data System (ADS)

    Berry, Mark Simpson

    The Environmental Protection Agency promulgated the Mercury and Air Toxics Standards rule, which requires that existing power plants reduce mercury emissions to meet an emission rate of 1.2 lb/TBtu on a 30-day rolling average and that new plants meet a 0.0002 lb/GWHr emission rate. This translates to mercury removals greater than 90% for existing units and greater than 99% for new units. Current state-of-the-art technology for the control of mercury emissions uses activated carbon injected upstream of a fabric filter, a costly proposition. For example, a fabric filter, if not already available, would require a 200M capital investment for a 700 MW size unit. A lower-cost option involves the injection of activated carbon into an existing cold-side electrostatic precipitator. Both options would incur the cost of activated carbon, upwards of 3M per year. The combination of selective catalytic reduction (SCR) reactors and wet flue gas desulphurization (wet FGD) systems have demonstrated the ability to substantially reduce mercury emissions, especially at units that burn coals containing sufficient halogens. Halogens are necessary for transforming elemental mercury to oxidized mercury, which is water-soluble. Plants burning halogen-deficient coals such as Power River Basin (PRB) coals currently have no alternative but to install activated carbon-based approaches to control mercury emissions. This research consisted of investigating calcium bromide addition onto PRB coal as a method of increasing flue gas halogen concentration. The treated coal was combusted in a 700 MW boiler and the subsequent treated flue gas was introduced into a wet FGD. Short-term parametric and an 83-day longer-term tests were completed to determine the ability of calcium bromine to oxidize mercury and to study the removal of the mercury in a wet FGD. The research goal was to show that calcium bromine addition to PRB coal was a viable approach for meeting the Mercury and Air Toxics Standards rule

  12. Preparation and evaluation of coal-derived activated carbons for removal of mercury vapor from simulated coal combustion flue fases

    USGS Publications Warehouse

    Hsi, H.-C.; Chen, S.; Rostam-Abadi, M.; Rood, M.J.; Richardson, C.F.; Carey, T.R.; Chang, R.

    1998-01-01

    Coal-derived activated carbons (CDACs) were tested for their suitability in removing trace amounts of vapor-phase mercury from simulated flue gases generated by coal combustion. CDACs were prepared in bench-scale and pilot-scale fluidized-bed reactors with a three-step process, including coal preoxidation, carbonization, and then steam activation. CDACs from high-organicsulfur Illinois coals had a greater equilibrium Hg0 adsorption capacity than activated carbons prepared from a low-organic-sulfur Illinois coal. When a low-organic-sulfur CDAC was impregnated with elemental sulfur at 600 ??C, its equilibrium Hg0 adsorption capacity was comparable to the adsorption capacity of the activated carbon prepared from the high-organicsulfur coal. X-ray diffraction and sulfur K-edge X-ray absorption near-edge structure examinations showed that the sulfur in the CDACs was mainly in organic forms. These results suggested that a portion of the inherent organic sulfur in the starting coal, which remained in the CDACs, played an important role in adsorption of Hg0. Besides organic sulfur, the BET surface area and micropore area of the CDACs also influenced Hg0 adsorption capacity. The HgCl2 adsorption capacity was not as dependent on the surface area and concentration of sulfur in the CDACs as was adsorption of Hg0. The properties and mercury adsorption capacities of the CDACs were compared with those obtained for commercial Darco FGD carbon.

  13. The ADESORB Process for Economical Production of Sorbents for Mercury Removal from Coal Fired Power Plants

    SciTech Connect

    Robin Stewart

    2008-03-12

    The DOE's National Energy Technology Laboratory (NETL) currently manages the largest research program in the country for controlling coal-based mercury emissions. NETL has shown through various field test programs that the determination of cost-effective mercury control strategies is complex and highly coal- and plant-specific. However, one particular technology has the potential for widespread application: the injection of activated carbon upstream of either an electrostatic precipitator (ESP) or a fabric filter baghouse. This technology has potential application to the control of mercury emissions on all coal-fired power plants, even those with wet and dry scrubbers. This is a low capital cost technology in which the largest cost element is the cost of sorbents. Therefore, the obvious solutions for reducing the costs of mercury control must focus on either reducing the amount of sorbent needed or decreasing the cost of sorbent production. NETL has researched the economics and performance of novel sorbents and determined that there are alternatives to the commercial standard (NORIT DARCO{reg_sign} Hg) and that this is an area where significant technical improvements can still be made. In addition, a key barrier to the application of sorbent injection technology to the power industry is the availability of activated carbon production. Currently, about 450 million pounds ($250 million per year) of activated carbon is produced and used in the U.S. each year - primarily for purification of drinking water, food, and beverages. If activated carbon technology were to be applied to all 1,100 power plants, EPA and DOE estimate that it would require an additional $1-$2 billion per year, which would require increasing current capacity by a factor of two to eight. A new facility to produce activated carbon would cost approximately $250 million, would increase current U.S. production by nearly 25%, and could take four to five years to build. This means that there could be

  14. Carbonized material adsorbents for the removal of mercury from aqueous solutions

    SciTech Connect

    1996-10-01

    Charcoal in itself is porous making it an excellent material for activated charcoal manufacture. However, few studies have been conducted in harnessing its potential for adsorption purposes, especially in water treatment. This paper describes the possibility of utilizing charcoal materials from Sugi (Cryptomeria japonica) for adsorbing heavy metals like mercury from aqueous solutions of different concentrations. The effect of soaking time, pore analyses and chemical properties on the adsorption capabilities of the carbonized materials were discussed. The pH value and chemical oxygen demand (COD) monitored during the soaking period were also described.

  15. Removal of mercury from aqueous solution using mesoporous silica nanoparticles modified with polyamide receptor.

    PubMed

    He, Chunsheng; Ren, Long; Zhu, Weiping; Xu, Yufang; Qian, Xuhong

    2015-11-15

    Based on the principle of supramolecular recognition and fluorescent chemical sensors, a novel kind of material for the separation of toxic heavy metal ions was designed and synthesized. Mesoporous silica nanoparticles MCM-41 with high surface areas and large ordered pores were used as the supporting matrix. Poly-amide derivative, was grafted to the mesoporous silica nanoparticles for extracting and separating trace Hg(2+) from aqueous solution, with a short adsorption time (t=3min) and a wide range of pH application (pH 3-11). The separation material could also extract trace mercury from Traditional Chinese Medicine, and has no influence on their effective components. PMID:26232282

  16. Mechanisms of mercury removal by biochars produced from different feedstocks determined using X-ray absorption spectroscopy.

    PubMed

    Liu, Peng; Ptacek, Carol J; Blowes, David W; Landis, Richard C

    2016-05-01

    Thirty-six biochars produced from distinct feedstocks at different temperatures were evaluated for their potential to remove mercury (Hg) from aqueous solution at environmentally relevant concentrations. Concentrations of total Hg (THg) decreased by >90% in batch systems containing biochars produced at 600 and 700 °C and by 40-90% for biochars produced at 300 °C. Elevated concentrations of SO4(2-) (up to 1000 mg L(-1)) were observed in solutions mixed with manure-based biochars. Sulfur X-ray absorption near edge structure (XANES) analyses indicate the presence of both reduced and oxidized S species in both unwashed and washed biochars. Sulfur XANES spectra obtained from biochars with adsorbed Hg were similar to those of washed biochars. Micro-X-ray fluorescence mapping results indicate that Hg was heterogeneously distributed across biochar particles. Extended X-ray absorption fine structure modeling indicates Hg was bound to S in biochars with high S content and to O and Cl in biochars with low S content. The predominant mechanisms of Hg removal are likely the formation of chemical bonds between Hg and various functional groups on the biochar. This investigation provides information on the effectiveness and mechanisms of Hg removal that is critical for evaluating biochar applications for stabilization of Hg in surface water, groundwater, soils, and sediments. PMID:26844404

  17. Bone char surface modification by nano-gold coating for elemental mercury vapor removal

    NASA Astrophysics Data System (ADS)

    Assari, Mohamad javad; Rezaee, Abbas; Rangkooy, Hossinali

    2015-07-01

    The present work was done to develop a novel nanocomposite using bone char coated with nano-gold for capture of elemental mercury (Hg0) from air. The morphologies, structures, and chemical constitute of the prepared nanocomposite were evaluated by UV-VIS-NIR, dynamic light-scattering (DLS), X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infra-red (FTIR) spectroscopy, and energy dispersive X-ray spectroscopy (EDS). The capture performance of nanocomposite was evaluated in a needle trap for mercury vapor. An on-line setup based on cold vapor atomic absorption spectrometry (CVAAS) was designed for Hg0 determination. Dynamic capacity of nanocomposite for Hg0 was shown high efficient operating capacity of 586.7 μg/g. As temperature increases, the dynamic adsorption capacity of the nanocomposite was decreased, which are characteristics of physicosorption processes. It was found that the surface modification of bone char with nano-gold has various advantages such as high operating dynamic adsorption capacity and low cost preparation. It was also demonstrated that the developed nanocomposite is suitable for on-line monitoring of Hg0. It could be applied for the laboratory and field studies.

  18. Removal of Mercury from SBW Vitrification Off-Gas by Activated Carbon

    SciTech Connect

    Deldebbio, John Anthony; Watson, T. T.; Kirkham, Robert John

    2001-09-01

    Radioactive, acidic waste stored at the Idaho Nuclear Technology and Engineering Center (INTEC) have been previously converted into a dry, granular solid at the New Waste Calcining Facility (NWCF). As an alternative to calcination, direct vitrification of the waste, as well as the calcined solids in an Idaho Waste Vitrification Facility (IWVF) is being considered to prepare the waste for final disposal in a federal repository. The remaining waste to be processed is Sodium-Bearing Waste (SBW). Off-gas monitoring during NWCF operations have indicated that future mercury emissions may exceed the proposed Maximum Achievable Control Technology (MACT) limit of 130 ug/dscm (micrograms/dry standard cubic meter) @ 7% O2 for existing Hazardous Waste Combustors (HWC) if modifications are not made. Carbon monoxide and hydrocarbon emissions may also exceed the MACT limits. Off-gas models have predicted that mercury levels in the off-gas from SBW vitrification will exceed the proposed MACT limit of 45 ug/dscm @ 7% O2 for new HWCs. NO2/44% H2O.

  19. FIELD TEST PROGRAM FOR LONG-TERM OPERATION OF A COHPAC SYSTEM FOR REMOVING MERCURY FROM COAL-FIRED FLUE GAS

    SciTech Connect

    Jean Bustard

    2003-06-13

    With the Nation's coal-burning utilities facing the possibility of tighter controls on mercury pollutants, the U.S. Department of Energy is funding projects that could offer power plant operators better ways to reduce these emissions at much lower costs. Sorbent injection technology represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. It involves injecting a solid material such as powdered activated carbon into the flue gas. The gas phase mercury in the flue gas contacts the sorbent and attaches to its surface. The sorbent with the mercury attached is then collected by the existing particle control device along with the other solid material, primarily fly ash. During 2001 ADA Environmental Solutions (ADA-ES) conducted a full-scale demonstration of sorbent-based mercury control technology at the Alabama Power E.C. Gaston Station (Wilsonville, AL). This unit burns a low-sulfur bituminous coal and uses a hot-side electrostatic precipitator (ESP) in combination with a COHPAC baghouse to collect fly ash. The majority of the fly ash is collected in the ESP with the residual being collected in the COHPAC baghouse. Activated carbon was injected between the ESP and COHPAC units to collect the mercury. Short-term mercury removal levels in excess of 90% were achieved using the COHPAC unit. The test also showed that activated carbon was effective on removing both forms of mercury, elemental and oxidized. However, a great deal of additional testing is required to further characterize the capabilities and limitations of this technology relative to use with baghouse systems such as COHPAC. It is important to determine performance over an extended period of time to fully assess all operational parameters. The project described in this report focuses on fully demonstrating sorbent injection technology at a coal-fired power generating plant that is equipped with a COHPAC system. The overall objective is to evaluate the

  20. FIELD TEST PROGRAM FOR LONG-TERM OPERATION OF A COHPAC SYSTEM FOR REMOVING MERCURY FROM COAL-FIRED FLUE GAS

    SciTech Connect

    Jean Bustard; Charles Lindsey; Paul Brignac; Travis Starns; Sharon Sjostrom; Trent Taylor; Cindy Larson

    2004-01-29

    With the Nation's coal-burning utilities facing the possibility of tighter controls on mercury pollutants, the U.S. Department of Energy is funding projects that could offer power plant operators better ways to reduce these emissions at much lower costs. Sorbent injection technology represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. It involves injecting a solid material such as powdered activated carbon into the flue gas. The gas-phase mercury in the flue gas contacts the sorbent and attaches to its surface. The sorbent with the mercury attached is then collected by the existing particle control device along with the other solid material, primarily fly ash. During 2001, ADA Environmental Solutions (ADA-ES) conducted a full-scale demonstration of sorbent-based mercury control technology at the Alabama Power E.C. Gaston Station (Wilsonville, AL). This unit burns a low-sulfur bituminous coal and uses a hot-side electrostatic precipitator (ESP) in combination with a Compact Hybrid Particulate Collector (COHPAC{trademark}) baghouse to collect fly ash. The majority of the fly ash is collected in the ESP with the residual being collected in the COHPAC{trademark} baghouse. Activated carbon was injected between the ESP and COHPAC{trademark} units to collect the mercury. Short-term mercury removal levels in excess of 90% were achieved using the COHPAC{trademark} unit. The test also showed that activated carbon was effective in removing both forms of mercury--elemental and oxidized. However, a great deal of additional testing is required to further characterize the capabilities and limitations of this technology relative to use with baghouse systems such as COHPAC{trademark}. It is important to determine performance over an extended period of time to fully assess all operational parameters. The project described in this report focuses on fully demonstrating sorbent injection technology at a coal-fired power

  1. Field Test Program for Long-Term Operation of a COHPAC System for Removing Mercury from Coal-Fired Flue Gas

    SciTech Connect

    Jean Bustard; Charles Lindsey; Paul Brignac; Travis Starns; Sharon Sjostrom; Trent Taylor; Cindy Larson

    2005-01-24

    With the Nation's coal-burning utilities facing the possibility of tighter controls on mercury pollutants, the U.S. Department of Energy is funding projects that could offer power plant operators better ways to reduce these emissions at much lower costs. Sorbent injection technology represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. It involves injecting a solid material such as powdered activated carbon into the flue gas. The gas-phase mercury in the flue gas contacts the sorbent and attaches to its surface. The sorbent with the mercury attached is then collected by the existing particle control device along with the other solid material, primarily fly ash. During 2001, ADA Environmental Solutions (ADA-ES) conducted a full-scale demonstration of sorbent-based mercury control technology at the Alabama Power E.C. Gaston Station (Wilsonville, Alabama). This unit burns a low-sulfur bituminous coal and uses a hot-side electrostatic precipitator (ESP) in combination with a Compact Hybrid Particulate Collector (COHPAC{reg_sign}) baghouse to collect fly ash. The majority of the fly ash is collected in the ESP with the residual being collected in the COHPAC{reg_sign} baghouse. Activated carbon was injected between the ESP and COHPAC{reg_sign} units to collect the mercury. Short-term mercury removal levels in excess of 90% were achieved using the COHPAC{reg_sign} unit. The test also showed that activated carbon was effective in removing both forms of mercury-elemental and oxidized. However, a great deal of additional testing is required to further characterize the capabilities and limitations of this technology relative to use with baghouse systems such as COHPAC{reg_sign}. It is important to determine performance over an extended period of time to fully assess all operational parameters. The project described in this report focuses on fully demonstrating sorbent injection technology at a coal-fired power

  2. Field Test Program for Long-Term Operation of a COHPAC System for Removing Mercury from Coal-Fired Flue Gas

    SciTech Connect

    Jean Bustard; Charles Lindsey; Paul Brignac; Travis Starns; Sharon Sjostrom; Trent Taylor; Cindy Larson

    2004-06-04

    With the Nation's coal-burning utilities facing the possibility of tighter controls on mercury pollutants, the U.S. Department of Energy is funding projects that could offer power plant operators better ways to reduce these emissions at much lower costs. Sorbent injection technology represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. It involves injecting a solid material such as powdered activated carbon into the flue gas. The gas-phase mercury in the flue gas contacts the sorbent and attaches to its surface. The sorbent with the mercury attached is then collected by the existing particle control device along with the other solid material, primarily fly ash. During 2001, ADA Environmental Solutions (ADA-ES) conducted a full-scale demonstration of sorbent-based mercury control technology at the Alabama Power E.C. Gaston Station (Wilsonville, Alabama). This unit burns a low-sulfur bituminous coal and uses a hot-side electrostatic precipitator (ESP) in combination with a Compact Hybrid Particulate Collector (COHPAC{reg_sign}) baghouse to collect fly ash. The majority of the fly ash is collected in the ESP with the residual being collected in the COHPAC{reg_sign} baghouse. Activated carbon was injected between the ESP and COHPAC{reg_sign} units to collect the mercury. Short-term mercury removal levels in excess of 90% were achieved using the COHPAC{reg_sign} unit. The test also showed that activated carbon was effective in removing both forms of mercury-elemental and oxidized. However, a great deal of additional testing is required to further characterize the capabilities and limitations of this technology relative to use with baghouse systems such as COHPAC{reg_sign}. It is important to determine performance over an extended period of time to fully assess all operational parameters. The project described in this report focuses on fully demonstrating sorbent injection technology at a coal-fired power

  3. Long-Term Carbon Injection Field Test for 90% Mercury Removal for a PRB Unit a Spray Dryer and Fabric Filter

    SciTech Connect

    Sjostrom, Sharon; Amrhein, Jerry

    2009-04-30

    The power industry in the U.S. is faced with meeting regulations to reduce the emissions of mercury compounds from coal-fired plants. Injecting a sorbent such as powdered activated carbon (PAC) into the flue gas represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. The purpose of this test program was to evaluate the long-term mercury removal capability, long-term mercury emissions variability, and operating and maintenance (O&M) costs associated with sorbent injection on a configuration being considered for many new plants. Testing was conducted by ADA Environmental Solutions (ADA) at Rocky Mountain Power’s (RMP) Hardin Station through funding provided by DOE/NETL, RMP, and other industry partners. The Hardin Station is a new plant rated at 121 MW gross that was first brought online in April of 2006. Hardin fires a Powder River Basin (PRB) coal and is configured with selective catalytic reduction (SCR) for NOx control, a spray dryer absorber (SDA) for SO2 control, and a fabric filter (FF) for particulate control. Based upon previous testing at PRB sites with SCRs, very little additional mercury oxidation from the SCR was expected at Hardin. In addition, based upon results from DOE/NETL Phase II Round I testing at Holcomb Station and results from similarly configured sites, low native mercury removal was expected across the SDA and FF. The main goal of this project was met—sorbent injection was used to economically and effectively achieve 90% mercury control as measured from the air heater (AH) outlet to the stack for a period of ten months. This goal was achieved with DARCO® Hg-LH, Calgon FLUEPAC®-MC PLUS and ADA Power PAC PREMIUM brominated activated carbons at nominal loadings of 1.5–2.5 lb/MMacf. An economic analysis determined the twenty-year levelized cost to be 0.87 mills/kW-hr, or $15,000/lb Hg removed. No detrimental effects on other equipment or plant operations were observed. The

  4. Simultaneous removal of acid green 25 and mercury ions from aqueous solutions using glutamine modified chitosan magnetic composite microspheres.

    PubMed

    Tao, Xue; Li, Kun; Yan, Han; Yang, Hu; Li, Aimin

    2016-02-01

    In this current work, the magnetic composite microsphere containing glutamine modified chitosan and silica coated Fe3O4 nanoparticles (CS-Gln-MCM) has been successfully prepared and extensively characterized, which is a kind of biodegradable materials. CS-Gln-MCM shows enhanced removal efficiency for both acid green 25 (AG25), an amphoteric dye, and mercury ions (Hg(2+)) from water in the respective while measured pH range compared with chitosan magnetic composite microsphere (CS-MCM) without modification. It is due to the fact that the grafted amino acid provides a variety of additional adsorption active sites and diverse adsorption mechanisms are involved. In AG25 and Hg(2+) aqueous mixture, the modified adsorbents bear preferential adsorption for AG25 over Hg(2+) in strong acidic solutions ascribed to multiple interactions between AG25 and CS-Gln-MCM, such as hydrogen bonding and electrostatic interactions. While, in weak acidic conditions, an efficient simultaneous removal is observed for different adsorption effects involved in aforementioned two pollutants. Besides, CS-Gln-MCM illuminates not only short equilibrium time for adsorption of each pollutant less than 20.0 min but also rapid magnetic separation from water and efficient regeneration after saturated adsorption. Therefore, CS-Gln-MCM bears great application potentials in water treatment. PMID:26618263

  5. Preparation of chitosan-graft-polyacrylamide magnetic composite microspheres for enhanced selective removal of mercury ions from water.

    PubMed

    Li, Kun; Wang, Yawen; Huang, Mu; Yan, Han; Yang, Hu; Xiao, Shoujun; Li, Aimin

    2015-10-01

    A novel magnetic composite microsphere based on polyacrylamide (PAM)-grafted chitosan and silica-coated Fe3O4 nanoparticles (CS-PAM-MCM) was successfully synthesized by a simple method. The molecular structure, surface morphology, and magnetic characteristics of the composite microsphere were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), vibrating-sample magnetometer (VSM), and scanning electron microscopy (SEM). The prepared CS-PAM-MCM was applied as an efficient adsorbent for the removal of copper(II), lead(II), and mercury(II) ions from aqueous solutions in respective single, binary, and ternary metal systems. Compared with chitosan magnetic composite microsphere (CS-MCM) without modification, CS-PAM-MCM showed improved adsorption capacity for each metal ion and highly selective adsorption for Hg from Pb and Cu. This improvement is attributed to the formation of stronger interactions between Hg and the amide groups of PAM branches for chelating effects. The adsorption isotherms of Hg/Cu and Hg/Pb binary metal systems onto CS-PAM-MCM are both well-described by extended and modified Langmuir models, indicating that the removal of the three aforementioned metal ions may follow a similar adsorption manner; that is, through a homogeneous monolayer chemisorption process. Furthermore, these magnetic adsorbents could be easily regenerated in EDTA aqueous solution and reused virtually without any adsorption capacity loss. PMID:26073848

  6. Novel Effective Catalyst for Elemental Mercury Removal from Coal-Fired Flue Gas and the Mechanism Investigation.

    PubMed

    Chen, Wanmiao; Pei, Yang; Huang, Wenjun; Qu, Zan; Hu, Xiaofang; Yan, Naiqiang

    2016-03-01

    Mercury pollution from coal-fired power plants has drawn attention worldwide. To achieve efficient catalytic oxidation of Hg(0) at both high and low temperatures, we prepared and tested novel IrO2 modified Ce-Zr solid solution catalysts under various conditions. It was found that the IrO2/Ce0.6Zr0.4O2 catalyst, which was prepared using the polyvinylpyrrolidone-assisted sol-gel method, displayed significantly higher catalytic activity for Hg(0) oxidation. The mechanism of Hg(0) removal over IrO2/Ce0.6Zr0.4O2 was studied using various methods, and the Hg(0) oxidation reaction was found to follow two possible pathways. For the new chemisorption-regeneration mechanism proposed in this study, the adsorbed Hg(0) was first oxidized with surface chemisorbed oxygen species to form HgO; the HgO could desorb from the surface of catalysts by itself or react with adsorbed HCl to be release in the form of gaseous HgCl2. O2 is indispensable for the chemisorption process, and the doping of IrO2 could facilitate the chemisorption process. In addition, the Deacon reaction mechanism was also feasible for Hg(0) oxidation: this reaction would involve first oxidizing the adsorbed HCl to active Cl species, after which the Hg(0) could react with Cl to form HgCl2. Additionally, doping IrO2 could significantly improve the Cl yield process. In summary, the novel IrO2 modified catalyst displayed excellent catalytic activity for elemental mercury oxidation, and the proposed reaction mechanisms were determined reasonably. PMID:26815147

  7. Mercury exposure aboard an ore boat.

    PubMed

    Roach, Richard R; Busch, Stephanie

    2004-06-01

    Two maritime academy interns (X and Y) were exposed to mercury vapor after spilling a bottle of mercury on the floor in an enclosed storeroom while doing inventory aboard an ore boat. During a 3-day period, intern Y suffered transient clinical intoxication that resolved after he was removed from the environment and he showered and discarded all clothing. His initial serum mercury level dropped from 4 ng/mL to < 0.05 ng/mL. Intern X had an initial level of 11 ng/mL, which continued to rise to a maximum of 188.8 ng/mL. He complained of tremulousness, insomnia, and mild agitation and was hospitalized. He had showered and discarded all clothing except his footwear earlier than intern Y. Intern X's continued exposure due to mercury in the contaminated boots during the 2 weeks before hospitalization was presumed to be the cause. Removing his footwear led to resolution of his toxic symptoms and correlated with subsequent lowered serum mercury levels. Chelation was initiated as recommended, despite its uncertain benefit for neurologic intoxication. Mercury is used in the merchant marine industry in ballast monitors called king gauges. New engineering is recommended for ballast monitoring to eliminate this hazard. PMID:15175181

  8. [Removal of gaseous elemental mercury over cerium doped low vanadium loading V2O5-WO3/TiO2 in simulated coal-fired flue gas].

    PubMed

    Wan, Qi; Duan, Lei; He, Ke-Bin; Chen, Liang; Li, Jun-Hua

    2011-09-01

    This paper discussed a recent study of mercury removal by gaseous hydrogen chloride over novel Ce doped low vanadium V2O5-WO3/TiO2 catalysts under a bench scale condition. The performances on Hg(0) removal over the catalyst were tested in simulated flue gas with 80-100 microg x m(-3) Hg(0), 8% O2, 10 x10(-6) HCl, 8% H2O, 800 x10(-6) SO2 and balanced with N2. Results showed that about 95% of Hg(0) could be removed. According to the characterization results, BET surface areas had not significant influence on catalytic performance. XPS results indicated that Ce4+ oxide was a mainly form in the catalysts surface, which was beneficial for Hg(0) removal reactions. Water vapor slightly inhibited Hg(0) removal efficiency, due to the competitive adsorption, however, SO2 promoted the oxidation reactions, resulting in higher removal efficiencies. PMID:22165254

  9. Synthesis and evaluation of different thio-modified cellulose resins for the removal of mercury (II) ion from highly acidic aqueous solutions.

    PubMed

    Takagai, Yoshitaka; Shibata, Atsushi; Kiyokawa, Shigemi; Takase, Tsugiko

    2011-01-15

    Seven different types of thio- and/or amine-modified cellulose resin materials were synthesized and their mercury (II) ion adsorption properties determined. All seven resins showed good mercury (II) adsorption capability in the more neutral pH regions. However, the o-benzenedithiol- and o-aminothiophenol-modified cellulosic resins were found to be very effective in removing mercury (II) ions from strongly acidic media. For example, 93.5-100% mercury (II) ion recoveries from very acid aqueous solutions (nitric acid concentration ranged from 0.1 to 2.0 mol/L) were obtained using the o-benzenedithiol-modified resin while recoveries ranged from ca. 50% to 60% for the o-aminothiophenol-modified resin. An adsorption capacity of 23 mg (as Hg atoms) per gram of resin was observed for the o-benzenedithiol-modified cellulose in the presence of 1.0 mol/L nitric acid. This same resin shows very good selectivity for mercury (II) as only ruthenium (II) also somewhat adsorbed onto it out of 14 other metal ions studied (Ag(+), Al(3+), As(3+), Co(2+), Cd(2+), Cr(3+), Cu(2+), Fe(3+), Mn(2+), Ni(2+), Pt(2+), Pb(2+), Ru(2+), and Zn(2+)). PMID:20974469

  10. Removal of mercury(II) from aqueous solutions and chlor-alkali industry wastewater using 2-mercaptobenzimidazole-clay.

    PubMed

    Manohar, D M; Krishnan, K Anoop; Anirudhan, T S

    2002-03-01

    The 2-mercaptobenzimidazole loaded natural clay was prepared for the removal of Hg(II) from aqueous media. Adsorption of the metal ions from aqueous solution as a function of solution concentration, agitation time, pH, temperature, ionic strength, particle size of the adsorbent and adsorbent dose was studied. The adsorption process follows a pseudo-second-order kinetics. The rate constants as a function of initial concentration and temperature were given. The adsorption of Hg(II) increased with increasing pH and reached a plateau value in the pH range 4.0-8.0. The removal of Hg(II) was found to be >99% at an initial concentration of 50 mg/l. Mercury(II) uptake was found to increase with ionic strength and temperature. Further, the adsorption of Hg(II) increased with increasing adsorbent dose and decrease with adsorbent particle size. Sorption data analysis was carried out using Langmuir and modified Langmuir isotherms for the uptake of metal ion in an initial concentration range of 50-1,000 mg/l. The significance of the two linear relationships obtained by plotting the data according to the conventional Langmuir equation is discussed in terms of the binding energies of the two population sites involved which have a widely differing affinity for Hg(II) ions. Thermodynamic parameters such as changes of free energy, enthalpy, and entropy were calculated to predict the nature of adsorption. It was found that the values of isosteric heat of adsorption were varied with surface loading. The chlor-alkali industry wastewater samples were treated by MBI-clay to demonstrate its efficiency in removing Hg(II) from wastewater. PMID:11996349

  11. Reactive iron sulfide (FeS)-supported ultrafiltration for removal of mercury (Hg(II)) from water.

    PubMed

    Han, Dong Suk; Orillano, Maria; Khodary, Ahmed; Duan, Yuhang; Batchelor, Bill; Abdel-Wahab, Ahmed

    2014-04-15

    This study investigated removal of Hg(II) from water using FeS(s) with batch and continuous contact filtration systems. For the batch system, kinetic experiments showed that removal of Hg(II) by FeS(s) was rapid at lower concentration (500 μM), but at higher concentration (1000 and 1250 μM), more time was required to achieve greater than 99% removal. The concentration of iron released to the solution remained relatively low, typically below 3 μM. This would theoretically present less than 1% of the Hg(II) removed. Thus, a simple exchange of Hg(II) for Fe(II) in the solid (FeS(s)) does not explain the results, but if the Fe(II) released could react to form another solids, low concentrations of Fe do not preclude a mechanism in which Hg(II) reacts to form HgS and release Fe(II). A continuous contact dead-end ultrafiltration (DE/UF) system was developed to treat water containing Hg(II) by applying a FeS(s) suspension with stirred or non-stirred modes. A major reason for applying stirring to the system was to investigate the role of "shear" flow in rejection of Hg(II)-contacted FeS(s) by a UF membrane and the stability of Hg on the FeS(s). The Hg(II)-contacted FeS(s) was completely rejected by the DE/UF system and mercury was strongly retained on the FeS(s) particles. Almost no release of Hg(II) (≈0 mM) from the FeS(s) solids was observed when they were contacted with 0.1M-thiosulfate, regardless of whether the system was operated in stirred or non-stirred mode. However, rapid oxidation of FeS(s) was observed in the stirred system but not in the non-stirred system. Determining the mechanism of oxidation requires further study, but it is important because oxidation reduces the ability of the solids to remove additional Hg(II). PMID:24530550

  12. Getting Mercury out of Schools.

    ERIC Educational Resources Information Center

    1999

    This guide was prepared while working with many Massachusetts schools to remove items that contain mercury and to find suitable alternatives. It contains fact sheets on: mercury in science laboratories and classrooms, mercury in school buildings and maintenance areas, mercury in the medical office and in medical technology classrooms in vocational…

  13. Mercury removal from contaminated groundwater: Performance and limitations of amalgamation through brass shavings.

    PubMed

    Richard, Jan-Helge; Biester, Harald

    2016-08-01

    Brass shavings have been proposed as a cost-effective filter material to remove Hg from contaminated groundwater. This method, which is based on the reduction of reactive Hg(II) and subsequent formation of amalgams, has been shown to be fast and effective in the short term. However, the effectiveness of brass filters and their stability over the long term, especially if used in passive filter systems such as permeable reactive barriers (PRB) under high flow conditions, is unknown. To evaluate the performance and limitations of brass shavings for Hg removal from contaminated groundwater, we performed long-term pilot scale filtration tests (6 and 28 months) at two former wood impregnation sites with severe groundwater contamination (up to 870 μg L(-1) Hg). The results showed that even under high flow conditions (>60 m d(-1)), 60-80% of the Hg was removed in the first 8 mm of the brass shavings filter bed. The kinetics of filtration, Hg total removal performance (>99.95%), and loading capacity (164 g L(-1)) surpassed those of a Hg-specific synthetic resin (LEWATIT(®)MonoPlus TP-214). However, under natural pH conditions (pH 6.4 and 6.7), Zn was leached from the brass and exceeded the threshold value (0.5 mg L(-1)) in the filter outflow by up to a factor of 40. Increasing pH (>8.5) decreased the Zn concentration (<0.05 mg L(-1)) but affected Hg removal due to the formation of Zn-hydroxide/carbonate coatings on the brass (up to 15% performance reduction). Thus, the use of brass shavings as an exclusive filter material in PRBs is restricted to aquifers with high pH. However, brass is ideal as a low-cost, thin-bed prefilter in onsite systems to remove the main Hg load from groundwater when Zn release is managed. PMID:27176550

  14. Magnetic self-assembled zeolite clusters for sensitive detection and rapid removal of mercury(II).

    PubMed

    Yin, Meili; Li, Zhenhua; Liu, Zhen; Yang, Xinjian; Ren, Jinsong

    2012-01-01

    We reported here the fabrication of a hierarchical mesoporous zeolite nanocomposite using 20 nm crystalline domins of zeolite L as building "bricks" by a simple and general one-step synthetic approach. By taking advantages of the large pore volumes, superparamagnetic iron oxide nanocrystals could be encapsulated into the nanocomposite conveniently for further facilitate separation and detection. In addition, by covalent coupling of fluorescent receptor (rhodamine-hydrazine), the combination of well-defined inorganic nanomaterials and organic receptors could be applied to selective detection of Hg(2+). Importantly, the unique adsorption capacity enabled by the hierarchical mesoporous zeolite and the efficient removal ability form complex multiphase systems by the magnetic characteristic made this multifunctional nanomaterial an excellent probe for detection, adsorption, and removal of Hg(2+) from waste aqueous solution. PMID:22126125

  15. Study on removal of elemental mercury from simulated flue gas over activated coke treated by acid

    NASA Astrophysics Data System (ADS)

    Ma, Jinfeng; Li, Caiting; Zhao, Lingkui; Zhang, Jie; Song, Jingke; Zeng, Guangming; Zhang, Xunan; Xie, Yine

    2015-02-01

    This work addressed the investigation of activated coke (AC) treated by acids. Effects of AC samples, modified by ether different acids (H2SO4, HNO3 and HClO4) or HClO4 of varied concentrations, on Hg0 removal were studied under simulated flue gas conditions. In addition, effects of reaction temperature and individual flue gas components including O2, NO, SO2 and H2O were discussed. In the experiments, Brunauer-Emmett-Teller (BET), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR) were applied to explore the surface properties of sorbents and possible mechanism of Hg0 oxidation. Results showed that AC sample treated by HClO4 of 4.5 mol/L exhibited maximum promotion of efficiency on Hg0 removal at 160 °C. NO was proved to be positive in the removal of Hg0. And SO2 displayed varied impact in capturing Hg0 due to the integrated reactions between SO2 and modified AC. The addition of O2 could improve the advancement further to some extent. Besides, the Hg0 removal capacity had a slight declination when H2O was added in gas flow. Based on the analysis of XPS and FTIR, the selected sample absorbed Hg0 mostly in chemical way. The reaction mechanism, deduced from results of characterization and performance of AC samples, indicated that Hg0 could firstly be absorbed on sorbent and then react with oxygen-containing (Csbnd O) or chlorine-containing groups (Csbnd Cl) on the surface of sorbent. And the products were mainly in forms of mercuric chloride (HgCl2) and mercuric oxide (HgO).

  16. Thermal removal of mercury in spent powdered activated carbon from TOXECON process

    SciTech Connect

    Okwadha, G.D.O.; Li, J.; Ramme, B.; Kollakowsky, D.; Michaud, D.

    2009-10-15

    This research developed and demonstrated a technology to liberate Hg adsorbed onto powdered activated carbon (PAC) by the TOXECON process using pilot-scale high temperature air slide (HTAS) and bench-scale thermogravimetric analyzer (TGA). The HTAS removed 65, 83, and 92% of Hg captured with PAC when ran at 900{sup o}F, 1,000{sup o}F, and 1,200 {sup o}F, respectively, while the TGA removed 46 and 100% of Hg at 800 {sup o}F and 900{sup o}F, respectively. However, addition of CuO-Fe{sub 2}O{sub 3} mixture and CuCl catalysts enhanced Hg removal and PAC regeneration at lower temperatures. CuO-Fe{sub 2}O{sub 3} mixture performed better than CuCl in PAC regeneration. Scanning electron microscopy images and energy dispersive X-ray analysis show no change in PAC particle aggregation or chemical composition. Thermally treated sorbents had higher surface area and pore volume than the untreated samples indicating regeneration. The optimum temperature for PAC regeneration in the HTAS was 1,000{sup o}F. At this temperature, the regenerated sorbent had sufficient adsorption capacity similar to its virgin counterpart at 33.9% loss on ignition. Consequently, the regenerated PAC may be recycled back into the system by blending it with virgin PAC.

  17. Development of silica/vanadia/titania catalysts for removal of elemental mercury from coal-combustion flue gas.

    PubMed

    Li, Ying; Murphy, Patrick D; Wu, Chang-Yu; Powers, Kevin W; Bonzongo, Jean-Claude J

    2008-07-15

    SiO2/V2O5/TiO2 catalysts were synthesized for removing elemental mercury (Hg0) from simulated coal-combustion flue gas. Experiments were carried out in fixed-bed reactors using both pellet and powder catalysts. In contrast to the SiO2-TiO2 composites developed in previous studies, the V2O5 based catalysts do not need ultraviolet light activation and have higher Hg0 oxidation efficiencies. For Hg0 removal by SiO2-V2O5 catalysts, the optimal V2O5 loading was found between 5 and 8%, which may correspond to a maximum coverage of polymeric vanadates on the catalyst surface. Hg0 oxidation follows an Eley-Rideal mechanism where HCI, NO, and NO2 are first adsorbed on the V2O5 active sites and then react with gas-phase Hg0. HCI, NO, and NO2 promote Hg oxidation, while SO2 has an insignificant effect and water vapor inhibits Hgo oxidation. The SiO2-TiO2-V2O5 catalysts exhibit greater Hg0 oxidation efficiencies than SiO2-V2O5, may be because the V-O-Ti bonds are more active than the V-O-Si bonds. This superior oxidation capability is advantageous to power plants equipped with wet-scrubbers where oxidized Hg can be easily captured. The findings in this work revealed the importance of optimizing the composition and microstructures of SCR (selective catalytic reduction) catalysts for Hg0 oxidation in coal-combustion flue gas. PMID:18754385

  18. Field Test Program for Long-Term Operation of a COHPAC System for Removing Mercury from Coal-Fired Flue Gas

    SciTech Connect

    C. Jean Bustard; Charles Lindsey; Paul Brignac

    2006-05-01

    This document provides a summary of the full-scale demonstration efforts involved in the project ''Field Test Program for Long-Term Operation of a COHPAC{reg_sign} System for Removing Mercury from Coal-Fired Flue Gas''. The project took place at Alabama Power's Plant Gaston Unit 3 and involved the injection of sorbent between an existing particulate collector (hot-side electrostatic precipitators) and a COHPAC{reg_sign} fabric filter (baghouse) downstream. Although the COHPAC{reg_sign} baghouse was designed originally for polishing the flue gas, when activated carbon injection was added, the test was actually evaluating the EPRI TOXECON{reg_sign} configuration. The results from the baseline tests with no carbon injection showed that the cleaning frequency in the COHPAC{reg_sign} unit was much higher than expected, and was above the target maximum cleaning frequency of 1.5 pulses/bag/hour (p/b/h), which was used during the Phase I test in 2001. There were times when the baghouse was cleaning continuously at 4.4 p/b/h. In the 2001 tests, there was virtually no mercury removal at baseline conditions. In this second round of tests, mercury removal varied between 0 and 90%, and was dependent on inlet mass loading. There was a much higher amount of ash exiting the electrostatic precipitators (ESP), creating an inlet loading greater than the design conditions for the COHPAC{reg_sign} baghouse. Tests were performed to try to determine the cause of the high ash loading. The LOI of the ash in the 2001 baseline tests was 11%, while the second baseline tests showed an LOI of 17.4%. The LOI is an indication of the carbon content in the ash, which can affect the native mercury uptake, and can also adversely affect the performance of ESPs, allowing more ash particles to escape the unit. To overcome this, an injection scheme was implemented that balanced the need to decrease carbon injection during times when inlet loading to the baghouse was high and increase carbon injection

  19. [Mercury in vaccines].

    PubMed

    Hessel, Luc

    2003-01-01

    Thiomersal, also called thimerosal, is an ethyl mercury derivative used as a preservative to prevent bacterial contamination of multidose vaccine vials after they have been opened. Exposure to low doses of thiomersal has essentially been associated with hypersensitivity reactions. Nevertheless there is no evidence that allergy to thiomersal could be induced by thiomersal-containing vaccines. Allergy to thiomersal is usually of delayed-hypersensitivity type, but its detection through cutaneous tests is not very reliable. Hypersensitivity to thiomersal is not considered as a contraindication to the use of thiomersal-containing vaccines. In 1999 in the USA, thiomersal was present in approximately 30 different childhood vaccines, whereas there were only 2 in France. Although there were no evidence of neurological toxicity in infants related to the use of thiomersal-containing vaccines, the FDA considered that the cumulative dose of mercury received by young infants following vaccination was high enough (although lower than the FDA threshold for methyl mercury) to request vaccine manufacturers to remove thiomersal from vaccine formulations. Since 2002, all childhood vaccines used in Europe and the USA are thiomersal-free or contain only minute amounts of thiomersal. Recently published studies have shown that the mercury levels in the blood, faeces and urine of children who had received thiomersal-containing vaccines were much lower than those accepted by the American Environmental Protection Agency. It has also been demonstrated that the elimination of mercury in children was much faster than what was expected on the basis of studies conducted with methyl mercury originating from food. Recently, the hypothesis that mercury contained in vaccines could be the cause of autism and other neurological developmental disorders created a new debate in the medical community and the general public. To date, none of the epidemiological studies conducted in Europe and elsewhere

  20. Influences of thermal decontamination on mercury removal, soil properties, and repartitioning of coexisting heavy metals.

    PubMed

    Huang, Yu-Tuan; Hseu, Zeng-Yei; Hsi, Hsing-Cheng

    2011-08-01

    Thermal treatment is a useful tool to remove Hg from contaminated soils. However, thermal treatment may greatly alter the soil properties and cause the coexisting contaminants, especially trace metals, to transform and repartition. The metal repartitioning may increase the difficulty in the subsequent process of a treatment train approach. In this study, three Hg-contaminated soils were thermally treated to evaluate the effects of treating temperature and duration on Hg removal. Thermogravimetric analysis was performed to project the suitable heating parameters for subsequent bench-scale fixed-bed operation. Results showed that thermal decontamination at temperature>400°C successfully lowered the Hg content to<20 mg kg(-1). The organic carbon content decreased by 0.06-0.11% and the change in soil particle size was less significant, even when the soils were thermally treated to 550°C. Soil clay minerals such as kaolinite were shown to be decomposed. Aggregates were observed on the surface of soil particles after the treatment. The heavy metals tended to transform into acid-extractable, organic-matter bound, and residual forms from the Fe/Mn oxide bound form. These results suggest that thermal treatment may markedly influence the effectiveness of subsequent decontamination methods, such as acid washing or solvent extraction. PMID:21624629

  1. Removal of antibiotics in wastewater by enzymatic treatment with fungal laccase - Degradation of compounds does not always eliminate toxicity.

    PubMed

    Becker, Dennis; Varela Della Giustina, Saulo; Rodriguez-Mozaz, Sara; Schoevaart, Rob; Barceló, Damià; de Cazes, Matthias; Belleville, Marie-Pierre; Sanchez-Marcano, José; de Gunzburg, Jean; Couillerot, Olivier; Völker, Johannes; Oehlmann, Jörg; Wagner, Martin

    2016-11-01

    In this study, the performance of immobilised laccase (Trametes versicolor) was investigated in combination with the mediator syringaldehyde (SYR) in removing a mixture of 38 antibiotics in an enzymatic membrane reactor (EMR). Antibiotics were spiked in osmosed water at concentrations of 10μg·L(-1) each. Laccase without mediator did not reduce the load of antibiotics significantly. The addition of SYR enhanced the removal: out of the 38 antibiotics, 32 were degraded by >50% after 24h. In addition to chemical analysis, the samples' toxicity was evaluated in two bioassays (a growth inhibition assay and the Microtox assay). Here, the addition of SYR resulted in a time-dependent increase of toxicity in both bioassays. In cooperation with SYR, laccase effectively removes a broad range of antibiotics. However, this enhanced degradation induces unspecific toxicity. If this issue is resolved, enzymatic treatment may be a valuable addition to existing water treatment technologies. PMID:27521787

  2. Enhanced Elemental Mercury Removal from Coal-fired Flue Gas by Sulfur-chlorine Compounds

    SciTech Connect

    Chang, Shih-Ger; Yan, Nai-Qiang; Qu, Zan; Chi, Yao; Qiao, Shao-Hua; Dod, Ray; Chang, Shih-Ger; Miller, Charles

    2008-07-02

    Oxidation of Hg0 with any oxidant or converting it to a particle-bound form can facilitate its removal. Two sulfur-chlorine compounds, sulfur dichloride (SCl2) and sulfur monochloride (S2Cl2), were investigated as oxidants for Hg0 by gas phase reaction and by surface-involved reactions in the presence of flyash or activated carbon. The gas phase reaction rate constants between Hg0 and the sulfur/chlorine compounds were determined, and the effects of temperature and the main components in flue gases were studied. The gas phase reaction between Hg0 and SCl2 is shown to be more rapid than the gas phase reaction with chlorine, and the second order rate constant was 9.1(+-0.5) x 10-18 mL-molecules-1cdots-1 at 373oK. Nitric oxide (NO) inhibited the gas phase reaction of Hg0 with sulfur-chlorine compounds. The presence of flyash or powdered activated carbon in flue gas can substantially accelerate the reaction. The predicted Hg0 removal is about 90percent with 5 ppm SCl2 or S2Cl2 and 40 g/m3 of flyash in flue gas. The combination of activated carbon and sulfur-chlorine compounds is an effective alternative. We estimate that co-injection of 3-5 ppm of SCl2 (or S2Cl2) with 2-3 Lb/MMacf of untreated Darco-KB is comparable in efficiency to the injection of 2-3 Lb/MMacf Darco-Hg-LH. Extrapolation of kinetic results also indicates that 90percent of Hg0 can be removed if 3 Lb/MMacf of Darco-KB pretreated with 3percent of SCl2 or S2Cl2 is used. Unlike gas phase reactions, NO exhibited little effect on Hg0 reactions with SCl2 or S2Cl2 on flyash or activated carbon. Mercuric sulfide was identified as one of the principal products of the Hg0/SCl2 or Hg0/S2Cl2 reactions. Additionally, about 8percent of SCl2 or S2Cl2 in aqueous solutions is converted to sulfide ions, which would precipitate mercuric ion from FGD solution.

  3. Enhanced elemental mercury removal from coal-fired flue gas by sulfur-chlorine compounds

    SciTech Connect

    Nai-Qiang Yan; Zan Qu; Yao Chi; Shao-Hua Qiao; Ray L. Dod; Shih-Ger Chang; Charles Miller

    2009-07-15

    Oxidation of Hg{sup 0} with any oxidant or converting it to a particle-bound form can facilitate its removal. Two sulfur-chlorine compounds, sulfur dichloride (SCl{sub 2}) and sulfur monochloride (S{sub 2}Cl{sub 2}), were investigated as oxidants for Hg{sup 0} by gas-phase reaction and by surface-involved reactions in the presence of flyash or activated carbon. The gas-phase reaction between Hg{sup 0} and SCl{sub 2} is shown to be more rapid than the gas-phase reaction with chlorine, and the second order rate constant was 9.1({+-}0.5) x 10{sup -18} mL-molecules{sup -1}.s{sup -1} at 373 K. The presence of flyash or powdered activated carbon in flue gas can substantially accelerate the reaction. The predicted Hg{sup 0} removal is about 90% with 5 ppm SCl {sub 2} or S{sub 2}Cl{sub 2} and 40 g/m{sup 3} of flyash in flue gas. The combination of activated carbon and sulfur-chlorine compounds is an effective alternative. We estimate that co-injection of 3-5 ppm of SCl{sub 2} (or S{sub 2}Cl{sub 2}) with 2-3 Lb/MMacf of untreated Darco-KB is comparable in efficiency to the injection of 2-3 Lb/MMacf Darco-Hg-LH. Extrapolation of kinetic results also indicates that 90% of Hg{sup 0} can be removed if 3 Lb/MMacf of Darco-KB pretreated with 3% of SCl{sub 2} or S{sub 2}Cl{sub 2} is used. Mercuric sulfide was identified as one of the principal products of the Hg{sup 0}/SCl{sub 2} or Hg{sup 0}/S{sub 2}Cl{sub 2} reactions. Additionally, about 8% of SCl{sub 2} or S{sub 2}Cl{sub 2} in aqueous solutions is converted to sulfide ions, which would precipitate mercuric ion from FGD solution. 14 refs., 5 figs., 1 tab.

  4. Study on the removal of elemental mercury from simulated flue gas by Fe₂O₃-CeO₂/AC at low temperature.

    PubMed

    Wang, Yan; Li, Caiting; Zhao, Lingkui; Xie, Yin'e; Zhang, Xunan; Zeng, Guangming; Wu, Huiyu; Zhang, Jie

    2016-03-01

    Fe2O3 and CeO2 modified activated coke (AC) synthesized by the equivalent-volume impregnation were employed to remove elemental mercury (Hg(0)) from simulated flue gas at a low temperature. Effects of the mass ratio of Fe2O3 and CeO2, reaction temperature, and individual flue gas components including O2, NO, SO2, and H2O (g) on Hg(0) removal efficiency of impregnated AC were investigated. The samples were characterized by Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). Results showed that with optimal mass percentage of 3 % Fe2O3 and 3 % CeO2 on Fe3Ce3/AC, the Hg(0) removal efficiency could reach an average of 88.29 % at 110 °C. Besides, it was observed that O2 and NO exhibited a promotional effect on Hg(0) removal, H2O (g) exerted a suppressive effect, and SO2 showed an insignificant inhibition without O2 to some extent. The analysis of XPS indicated that the main species of mercury on used Fe3Ce3/AC was HgO, which implied that adsorption and catalytic oxidation were both included in Hg(0) removal. Furthermore, the lattice oxygen, chemisorbed oxygen, and/or weakly bonded oxygen species made a contribution to Hg(0) oxidation. PMID:26552788

  5. Got Mercury?

    NASA Technical Reports Server (NTRS)

    Meyers, Valerie; James, John T.; McCoy, Torin; Garcia, Hector

    2010-01-01

    Many lamps used in various spacecraft contain elemental mercury, which is efficiently absorbed through the lungs as a vapor. The liquid metal vaporizes slowly at room temperature, but may be completely vaporized when lamps are operating. Because current spacecraft environmental control systems are unable to remove mercury vapors, we considered short-term and long-term exposures. Using an existing study, we estimated mercury vapor releases from lamps that are not in operation during missions lasting less than or equal to 30 days; whereas we conservatively assumed complete vaporization from lamps that are operating or being used during missions lasing more than 30 days. Based on mercury toxicity, the Johnson Space Center's Toxicology Group recommends stringent safety controls and verifications for any hardware containing elemental mercury that could yield airborne mercury vapor concentrations greater than 0.1 mg/m3 in the total spacecraft atmosphere for exposures lasting less than or equal to 30 days, or concentrations greater than 0.01 mg/m3 for exposures lasting more than 30 days.

  6. Investigating the Temporal Effects of Metal-Based Coagulants to Remove Mercury from Solution in the Presence of Dissolved Organic Matter.

    PubMed

    Henneberry, Yumiko; Kraus, Tamara E C; Krabbenhoft, David P; Horwath, William R

    2016-01-01

    The presence of mercury (Hg), particularly methylmercury (MeHg), is a concern for both human and ecological health as MeHg is a neurotoxin and can bioaccumulate to lethal levels in upper trophic level organisms. Recent research has demonstrated that coagulation with metal-based salts can effectively remove both inorganic mercury (IHg) and MeHg from solution through association with dissolved organic matter (DOM) and subsequent flocculation and precipitation. In this study, we sought to further examine interactions between Hg and DOM and the resulting organo-metallic precipitate (floc) to assess if (1) newly added IHg could be removed to the same extent as ambient IHg or whether the association between IHg and DOM requires time, and (2) once formed, if the floc has the capacity to remove additional Hg from solution. Agricultural drainage water samples containing ambient concentrations of both DOM and IHg were spiked with a traceable amount of isotopically enriched IHg and dosed with ferric sulfate after 0, 1, 5, and 30 days. Both ambient and newly added IHg were removed within hours, with 69-79 % removed. To a separate sample set, isotopically enriched IHg was added to solution after floc had formed. Under those conditions, 81-95 % of newly added Hg was removed even at Hg concentrations 1000-fold higher than ambient levels. Results of this study indicate coagulation with ferric sulfate effectively removes both ambient and newly added IHg entering a system and suggests rapid association between IHg and DOM. This work also provides new information regarding the ability of floc to remove additional Hg from solution even after it has formed. PMID:26330169

  7. Investigating the Temporal Effects of Metal-Based Coagulants to Remove Mercury from Solution in the Presence of Dissolved Organic Matter

    NASA Astrophysics Data System (ADS)

    Henneberry, Yumiko; Kraus, Tamara E. C.; Krabbenhoft, David P.; Horwath, William R.

    2016-01-01

    The presence of mercury (Hg), particularly methylmercury (MeHg), is a concern for both human and ecological health as MeHg is a neurotoxin and can bioaccumulate to lethal levels in upper trophic level organisms. Recent research has demonstrated that coagulation with metal-based salts can effectively remove both inorganic mercury (IHg) and MeHg from solution through association with dissolved organic matter (DOM) and subsequent flocculation and precipitation. In this study, we sought to further examine interactions between Hg and DOM and the resulting organo-metallic precipitate (floc) to assess if (1) newly added IHg could be removed to the same extent as ambient IHg or whether the association between IHg and DOM requires time, and (2) once formed, if the floc has the capacity to remove additional Hg from solution. Agricultural drainage water samples containing ambient concentrations of both DOM and IHg were spiked with a traceable amount of isotopically enriched IHg and dosed with ferric sulfate after 0, 1, 5, and 30 days. Both ambient and newly added IHg were removed within hours, with 69-79 % removed. To a separate sample set, isotopically enriched IHg was added to solution after floc had formed. Under those conditions, 81-95 % of newly added Hg was removed even at Hg concentrations 1000-fold higher than ambient levels. Results of this study indicate coagulation with ferric sulfate effectively removes both ambient and newly added IHg entering a system and suggests rapid association between IHg and DOM. This work also provides new information regarding the ability of floc to remove additional Hg from solution even after it has formed.

  8. Investigating the temporal effects of metal-based coagulants to remove mercury from solution in the presence of dissolved organic matter

    USGS Publications Warehouse

    Henneberry, Yumiko K.; Kraus, Tamara; Krabbenhoft, David P.; Horwath, William R.

    2015-01-01

    The presence of mercury (Hg), particularly methylmercury (MeHg), is a concern for both human and ecological health as MeHg is a neurotoxin and can bioaccumulate to lethal levels in upper trophic level organisms. Recent research has demonstrated that coagulation with metal-based salts can effectively remove both inorganic mercury (IHg) and MeHg from solution through association with dissolved organic matter (DOM) and subsequent flocculation and precipitation. In this study, we sought to further examine interactions between Hg and DOM and the resulting organo-metallic precipitate (floc) to assess if (1) newly added IHg could be removed to the same extent as ambient IHg or whether the association between IHg and DOM requires time, and (2) once formed, if the floc has the capacity to remove additional Hg from solution. Agricultural drainage water samples containing ambient concentrations of both DOM and IHg were spiked with a traceable amount of isotopically enriched IHg and dosed with ferric sulfate after 0, 1, 5, and 30 days. Both ambient and newly added IHg were removed within hours, with 69–79 % removed. To a separate sample set, isotopically enriched IHg was added to solution after floc had formed. Under those conditions, 81–95 % of newly added Hg was removed even at Hg concentrations 1000-fold higher than ambient levels. Results of this study indicate coagulation with ferric sulfate effectively removes both ambient and newly added IHg entering a system and suggests rapid association between IHg and DOM. This work also provides new information regarding the ability of floc to remove additional Hg from solution even after it has formed.

  9. The Use of Haz-Flote to Efficiently Remove Mercury from Contaminated Materials

    SciTech Connect

    Terry Brown

    2009-03-03

    There are thousands of known contaminated sites in the United Stated, including Superfund sites (1500 to 2100 sites), RCRA corrective action sites (1500 to 3500 sites), underground storage tanks (295,000 sites), U.S. Department of Defense sites (7300 sites), U.S. Department of Energy sites (4,000 sites), mining refuse piles, and numerous other hazardous metals and organic contamination sites. Only a small percentage of these sites has been cleaned up. The development of innovative technologies to handle the various clean-up problems on a national and international scale is commonplace. Many innovative technologies have been developed that can be used to effectively remediate contaminated materials. Unfortunately, many of these technologies are only effective for materials coarser than approximately 200 mesh. In addition, these technologies usually require considerable investment in equipment, and the clean-up costs of soil material are relatively high - in excess of $100 to $500 per yd{sup 3}. These costs result from the elaborate nature of the processes, the costs for power, and the chemical cost. The fine materials are disposed of or treated at considerable costs. As a result, the costs often associated with amelioration of contaminated sites are high. Western Research institute is in the process of developing an innovative soil washing technology that addresses the removal of contaminants from the fine size-fraction materials located at many of the contaminated sites. This technology has numerous advantages over the other ex-situ soil washing techniques. It requires a low capital investment, low operating costs and results in high levels of re-emplacement of the cleaned material on site. The process has the capability to clean the fine fraction (<200 mesh) of the soil resulting in a replacement of 95+% of the material back on-side, reducing the costs of disposal. The Haz-Flote{trademark} technology would expand the application of soil washing technology to heavy

  10. Development of silica/vanadia/titania catalysts for removal of elemental mercury from coal-combustion flue gas

    SciTech Connect

    Ying Li; Patrick D. Murphy; Chang-Yu Wu; Kevin W. Powers; Jean-Claude J. Bonzongo

    2008-07-15

    SiO{sub 2}/V{sub 2}O{sub 5}/TiO{sub 2} catalysts were synthesized for removing elemental mercury (Hg{sup 0}) from simulated coal-combustion flue gas. Experiments were carried out in fixed-bed reactors using both pellet and powder catalysts. In contrast to the SiO{sub 2}-TiO{sub 2} composites developed in previous studies, the V{sub 2}O{sub 5} based catalysts do not need ultraviolet light activation and have higher Hg{sup 0} oxidation efficiencies. For Hg{sup 0} removal by SiO{sub 2}-V{sub 2}O{sub 5} catalysts, the optimal V{sub 2}O{sub 5} loading was found between 5 and 8%, which may correspond to a maximum coverage of polymeric vanadates on the catalyst surface. Hg{sup 0} oxidation follows an Eley-Rideal mechanism where HCl, NO, and NO{sub 2} are first adsorbed on the V{sub 2}O{sub 5} active sites and then react with gas-phase Hg{sup 0}. HCl, NO, and NO{sub 2} promote Hg oxidation, while SO{sub 2} has an insignificant effect and water vapor inhibits Hg{sup 0} oxidation. The SiO{sub 2}-TiO{sub 2}-V{sub 2}O{sub 5} catalysts exhibit greater Hg{sup 0} oxidation efficiencies than SiO{sub 2}-V{sub 2}O{sub 5}, may be because the V-O-Ti bonds are more active than the V-O-Si bonds. This superior oxidation capability is advantageous to power plants equipped with wet-scrubbers where oxidized Hg can be easily captured. The findings in this work revealed the importance of optimizing the composition and microstructures of SCR (selective catalytic reduction) catalysts for Hg{sup 0} oxidation in coal-combustion flue gas. 33 refs., 5 figs., 2 tabs.

  11. Removal of mercury(II) ions in aqueous solution using the peel biomass of Pachira aquatica Aubl: kinetics and adsorption equilibrium studies.

    PubMed

    Santana, Andrea J; Dos Santos, Walter N L; Silva, Laiana O B; das Virgens, Cesário F

    2016-05-01

    Mercury is a highly toxic substance that is a health hazard to humans. This study aims to investigate powders obtained from the peel of the fruit of Pachira aquatica Aubl, in its in natura and/or acidified form, as an adsorbent for the removal of mercury ions in aqueous solution. The materials were characterized by Fourier transform infrared spectroscopy and thermogravimetric analysis. The infrared spectra showed bands corresponding to the axial deformation of carbonyls from carboxylic acids, the most important functional group responsible for fixing the metal species to the adsorbent material. The thermograms displayed mass losses related to the decomposition of three major components, i.e., hemicellulose, cellulose, and lignin. The adsorption process was evaluated using cold-vapor atomic fluorescence spectrometry (CV AFS) and cold-vapor atomic absorption spectrometry (CV AAS). Three isotherm models were employed. The adsorption isotherm model, Langmuir-Freundlich, best represented the adsorption process, and the maximum adsorption capacity was predicted to be 0.71 and 0.58 mg g(-1) at 25 °C in nature and acidified, respectively. Adsorption efficiencies were further tested on real aqueous wastewater samples, and removal of Hg(II) was recorded as 69.6 % for biomass acidified and 76.3 % for biomass in nature. Results obtained from sorption experiments on real aqueous wastewater samples revealed that recovery of the target metal ions was very satisfactory. The pseudo-second-order model showed the best correlation to the experimental data. The current findings showed that the investigated materials are potential adsorbents for mercury(II) ion removal in aqueous solution, with acidified P. aquatica Aubl being the most efficient adsorbent. PMID:27084802

  12. Facile synthesis of ternary Ag/AgBr-Ag2CO3 hybrids with enhanced photocatalytic removal of elemental mercury driven by visible light.

    PubMed

    Zhang, Anchao; Zhang, Lixiang; Lu, Hao; Chen, Guoyan; Liu, Zhichao; Xiang, Jun; Sun, Lushi

    2016-08-15

    A novel technique for photocatalytic removal of elemental mercury (Hg(0)) using visible-light-driven Ag/AgBr-Ag2CO3 hybrids was proposed. The ternary Ag/AgBr-Ag2CO3 hybrids were synthesized by a simple modified co-precipitation method and characterized by N2 adsorption-desorption, scanning electron microscope (SEM), X-ray diffraction (XRD), UV-vis diffused reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS) and electron spin resonance (ESR) techniques. The effects of AgBr content, fluorescent lamp (FSL) irradiation, solution temperature, SO2 and NO on Hg(0) removal were investigated in detail. Furthermore, a possible reaction mechanism for higher Hg(0) removal was proposed, and the simultaneous removal of Hg(0), SO2 and NO was studied. The results showed that a high efficiency of Hg(0) removal was obtained by using Ag/AgBr-Ag2CO3 hybrids under fluorescent lamp irradiation. The AgBr content, FSL irradiation, solution temperature, and SO2 all exhibited significant effects on Hg(0) removal, while NO had slight effect on Hg(0) removal. The addition of Ca(OH)2 demonstrated a little impact on Hg(0) removal and could significantly improve the SO2-resistance performance of Ag/AgBr(0.7)-Ag2CO3 hybrid. The characterization results exhibited that hydroxyl radical (OH), superoxide radical (O2(-)), hole (h(+)), and Br(0), were reactive species responsible for removing Hg(0), and the h(+) played a key role in Hg(0) removal. PMID:27135702

  13. Elimination of As, Hg and Zn from synthetic solutions and industrial effluents using modified bark

    SciTech Connect

    Gaballah, I.; Kilbertus, G.

    1995-08-01

    Elimination of arsenic, mercury and zinc from synthetic solutions containing H{sub 3}AsO{sub 4}, HgCl{sub 2} and ZnCl{sub 2} using modified barks was investigated. The pH range was varied from 1 to 10. The initial concentrations of individual element were 10, 100 and 1,000 ppm. More than 99% of mercury and 65% of zinc cations were removed by the modified bark. In this case, the modified bark reacts as a cation exchanger leading to the release of two protons for every Hg{sup II} or Zn{sup II} fixed by this material. About 30% of arsenic was eliminated from the solution. This low efficiency could be attributed to the presence of arsenic as anion. Decontamination of a treated industrial effluent containing 4 ppm of ion metals was performed on a pilot scale by the modified bark. More than 70% of these ion metals were eliminated.

  14. Getting rid of mercury

    SciTech Connect

    Reisch, M.S.

    2008-11-24

    Anticipating a US rule on mercury removal from coal flue gas, technology providers jockey for position. By 2013, if the federal rule imposing regulation of mercury emissions which have begun or are about to begin in 20 eastern states goes nationwide, mercury control will be big business. For the near term, utilities are adopting activated carbon to control mercury emissions. McIlvaine Co. projects the US market for activated carbon will jump from 10 million lb in 2010 to 350 million by 2013. Norit and Calgon Carbon are already increasing production of activated carbon (mainly from coal) and ADA Environmental Solutions (ADA-ES) is building a new plant. Albermarle is developing a process to treat activated carbon with bromine; Corning has developed a sulfur impregnated activated carbon filtration brick. New catalysts are being developed to improve the oxidation of mercury for removal from flue gas. 2 photos.

  15. Sources of Mercury to East Fork Poplar Creek Downstream from the Y-12 National Security Complex: Inventories and Export Rates

    SciTech Connect

    Southworth, George R; Greeley Jr, Mark Stephen; Peterson, Mark J; Lowe, Kenneth Alan; Ketelle, Richard H; Floyd, Stephanie B

    2010-02-01

    East Fork Poplar Creek (EFPC) in Oak Ridge, Tennessee, has been heavily contaminated with mercury (also referred to as Hg) since the 1950s as a result of historical activities at the U.S. Department of Energy (DOE) Y-12 National Security Complex (formerly the Oak Ridge Y-12 Plant and hereinafter referred to as Y-12). During the period from 1950 to 1963, spills and leaks of elemental mercury (Hg{sup 0}) contaminated soil, building foundations, and subsurface drainage pathways at the site, while intentional discharges of mercury-laden wastewater added 100 metric tons of mercury directly to the creek (Turner and Southworth 1999). The inventory of mercury estimated to be lost to soil and rock within the facility was 194 metric tons, with another estimated 70 metric tons deposited in floodplain soils along the 25 km length of EFPC (Turner and Southworth 1999). Remedial actions within the facility reduced mercury concentrations in EFPC water at the Y-12 boundary from > 2500 ng/L to about 600 ng/L by 1999 (Southworth et al. 2000). Further actions have reduced average total mercury concentration at that site to {approx}300 ng/L (2009 RER). Additional source control measures planned for future implementation within the facility include sediment/soil removal, storm drain relining, and restriction of rainfall infiltration within mercury-contaminated areas. Recent plans to demolish contaminated buildings within the former mercury-use areas provide an opportunity to reconstruct the storm drain system to prevent the entry of mercury-contaminated water into the flow of EFPC. Such actions have the potential to reduce mercury inputs from the industrial complex by perhaps as much as another 80%. The transformation and bioaccumulation of mercury in the EFPC ecosystem has been a perplexing subject since intensive investigation of the issue began in the mid 1980s. Although EFPC was highly contaminated with mercury (waterborne mercury exceeded background levels by 1000-fold, mercury in

  16. MODELING MERCURY CONTROL WITH POWDERED ACTIVATED CARBON

    EPA Science Inventory

    The paper presents a mathematical model of total mercury removed from the flue gas at coal-fired plants equipped with powdered activated carbon (PAC) injection for Mercury control. The developed algorithms account for mercury removal by both existing equipment and an added PAC in...

  17. Mercury capture in bench-scale absorbers

    SciTech Connect

    Livengood, C.D.; Huang, H.S.; Mendelsohn, M.H.; Wu, J.M.

    1994-08-01

    This paper gives,a brief overview of research being conducted at Argonne National Laboratory on the capture of mercury by both dry sorbents and wet scrubbers. The emphasis in the research is on development of a better understanding of the key factors that control the capture of mercury. Future work is expected to utilize that information for the development of new or modified process concepts featuring enhanced mercury capture capabilities. The results and conclusions to date from the Argonne -research on dry sorbents can be summarized as follows: lime hydrates, either regular or high-surface-area, are `not effective in removing mercury; mercury removals are enhanced by the addition of activated carbon; mercury removals with activated carbon decrease with increasing temperature, larger particle size, and decreasing mercury concentration in the gas; and chemical pretreatment (e.g., with sulfur or (CaCl{sub 2}) can greatly increase the removal capacity of activated carbon. Preliminary results from the wet scrubbing research include: no removal of elemental mercury is obtained under normal scrubber operating conditions; mercury removal is improved by the addition of packing or production of smaller gas bubbles to increase the gas-liquid contact area; polysulfide solutions do not appear promising for enhancing mercury removal in typical FGC systems; stainless steel packing appears to have beneficial properties for mercury removal and should be investigated further; and other chemical additives may offer greatly enhanced removals.

  18. Investigation of Elimination Rate, Persistent Subpopulation Removal, and Relapse Rates of Mycobacterium tuberculosis by Using Combinations of First-Line Drugs in a Modified Cornell Mouse Model.

    PubMed

    Hu, Yanmin; Pertinez, Henry; Ortega-Muro, Fatima; Alameda-Martin, Laura; Liu, Yingjun; Schipani, Alessandro; Davies, Geraint; Coates, Anthony

    2016-08-01

    Currently, the most effective tuberculosis control method involves case finding and 6 months of chemotherapy. There is a need to improve our understanding about drug interactions, combination activities, and the ability to remove persistent bacteria using the current regimens, particularly in relation to relapse. We aimed to investigate the therapeutic effects of three main components, rifampin (RMP), isoniazid (INH), and pyrazinamide (PZA), in current drug regimens using a modified version of the Cornell mouse model. We evaluated the posttreatment levels of persistent Mycobacterium tuberculosis in the organs of mice using culture filtrate derived from M. tuberculosis strain H37Rv. When RMP was combined with INH, PZA, or INH-PZA, significant additive activities were observed compared to each of the single-drug treatments. However, the combination of INH and PZA showed a less significant additive effect than either of the drugs used on their own. Apparent culture negativity of mouse organs was achieved at 14 weeks of treatment with RMP-INH, RMP-PZA, and RMP-INH-PZA, but not with INH-PZA, when conventional tests, namely, culture on solid agar and in liquid broth, indicated that the organs were negative for bacteria. The relapse rates for RMP-containing regimens were not significantly different from a 100% relapse rate at the numbers of mice examined in this study. In parallel, we examined the organs for the presence of culture filtrate-dependent persistent bacilli after 14 weeks of treatment. Culture filtrate treatment of the organs revealed persistent M. tuberculosis Modeling of mycobacterial elimination rates and evaluation of culture filtrate-dependent organisms showed promise as surrogate methods for efficient factorial evaluation of drug combinations in tuberculosis in mouse models and should be further evaluated against relapse. The presence of culture filtrate-dependent persistent M. tuberculosis is the likely cause of disease relapse in this modified Cornell

  19. Investigation of Elimination Rate, Persistent Subpopulation Removal, and Relapse Rates of Mycobacterium tuberculosis by Using Combinations of First-Line Drugs in a Modified Cornell Mouse Model

    PubMed Central

    Pertinez, Henry; Ortega-Muro, Fatima; Alameda-Martin, Laura; Liu, Yingjun; Schipani, Alessandro; Davies, Geraint; Coates, Anthony

    2016-01-01

    Currently, the most effective tuberculosis control method involves case finding and 6 months of chemotherapy. There is a need to improve our understanding about drug interactions, combination activities, and the ability to remove persistent bacteria using the current regimens, particularly in relation to relapse. We aimed to investigate the therapeutic effects of three main components, rifampin (RMP), isoniazid (INH), and pyrazinamide (PZA), in current drug regimens using a modified version of the Cornell mouse model. We evaluated the posttreatment levels of persistent Mycobacterium tuberculosis in the organs of mice using culture filtrate derived from M. tuberculosis strain H37Rv. When RMP was combined with INH, PZA, or INH-PZA, significant additive activities were observed compared to each of the single-drug treatments. However, the combination of INH and PZA showed a less significant additive effect than either of the drugs used on their own. Apparent culture negativity of mouse organs was achieved at 14 weeks of treatment with RMP-INH, RMP-PZA, and RMP-INH-PZA, but not with INH-PZA, when conventional tests, namely, culture on solid agar and in liquid broth, indicated that the organs were negative for bacteria. The relapse rates for RMP-containing regimens were not significantly different from a 100% relapse rate at the numbers of mice examined in this study. In parallel, we examined the organs for the presence of culture filtrate-dependent persistent bacilli after 14 weeks of treatment. Culture filtrate treatment of the organs revealed persistent M. tuberculosis. Modeling of mycobacterial elimination rates and evaluation of culture filtrate-dependent organisms showed promise as surrogate methods for efficient factorial evaluation of drug combinations in tuberculosis in mouse models and should be further evaluated against relapse. The presence of culture filtrate-dependent persistent M. tuberculosis is the likely cause of disease relapse in this modified Cornell

  20. Selective and Efficient Removal of Mercury from Aqueous Media with the Highly Flexible Arms of a BioMOF.

    PubMed

    Mon, Marta; Lloret, Francesc; Ferrando-Soria, Jesús; Martí-Gastaldo, Carlos; Armentano, Donatella; Pardo, Emilio

    2016-09-01

    A robust and water-stable metal-organic framework (MOF), featuring hexagonal channels decorated with methionine residues (1), selectively captures toxic species such as CH3 Hg(+) and Hg(2+) from water. 1 exhibits the largest Hg(2+) uptake capacity ever reported for a MOF, decreasing the [Hg(2+) ] and [CH3 Hg(+) ] concentrations in potable water from highly hazardous 10 ppm to the much safer values of 6 and 27 ppb, respectively. Just like with biological systems, the high-performance metal capture also involves a molecular recognition process. Both CH3 Hg(+) and Hg(2+) are efficiently immobilized by specific conformations adopted by the flexible thioether "claws" decorating the pores of 1. This leads to very stable structural conformations reminiscent of those responsible for the biological activity of the enzyme mercury reductase (MR). PMID:27529544

  1. Effective removal of mercury(II) ions from chlor-alkali industrial wastewater using 2-mercaptobenzamide modified itaconic acid-grafted-magnetite nanocellulose composite.

    PubMed

    Anirudhan, T S; Shainy, F

    2015-10-15

    A novel adsorbent, 2-mercaptobenzamide modified itaconic acid-grafted-magnetite nanocellulose composite [P(MB-IA)-g-MNCC] was synthesized for adsorbing mercury(II) [Hg(II)] ions selectively from aqueous solutions. Fourier transforms infrared spectroscopy, X-ray diffraction, scanning electron microscopy and thermogravimetric studies were performed to characterize the adsorbent. The optimum pH for Hg(II) adsorption was found to be 8.0, and the adsorption attained equilibrium within 60 min. The kinetic data were found to follow pseudo-second-order which assumes the ion exchange followed by complexation mechanism. The temperature dependence indicates an exothermic process. The well agreement of equilibrium data with Freundlich adsorption model confirms the multilayer coverage of Hg(II) onto P(MB-IA)-g-MNCC. The maximum adsorption capacity was found to be 240.0 mg/g. Complete removal of Hg(II) from aqueous solution was possible with an adsorbent dosage of 2.0 g/L. Spent adsorbent was effectively degenerated with 0.1M HCl. The present investigation shows that P(MB-IA)g-MNCC is a promising adsorbent for the removal and recovery of Hg(II) ions from aqueous solutions. PMID:26086434

  2. Studies on thio-substituted polyurethane foam (T-PUF) as a new efficient separation medium for the removal of inorganic/organic mercury from industrial effluents and solid wastes.

    PubMed

    Anjaneyulu, Y; Marayya, R; Rao, T H

    1993-01-01

    Novel thio-substituted flexible polyurethane foam (T-PUF) was synthesised by addition polymerisation of mercaptan with the precursors of an open-cell polyurethane foam, which can be used as a highly selective sorbent for inorganic and organic mercury from complex matrices. The percentage extraction of inorganic mercury was studied at different flow-rates, over a wide pH range at different concentrations ranging from 1 ppm, to 100 ppm. The break-through capacity and total capacity of unmodified and thio-foams were determined for inorganic and organic mercurials. The absorption efficiency of thio-foam was far superior to other sorbent media, such as activated carbon, polymeric ion-exchange resins and reagent-loaded polyurethane foams. It was observed that even at the 1000 ppm level, divalent ions like Cu, Mg, Ca, Zn do not appreciably influence the per cent extraction of inorganic mercury at the 10 ppm level. These matrix levels are the most concentrated ones which are likely to occur, both in local sewage and effluent waters. Further, the efficiency of this foam was sufficiently high at 10-100 ppm levels of Hg, even from 5-10 litres of effluent volumes using 50 g of thio-foam packed into different columns in series. Thio-foams were found to possess excellent abilities to remove and recover mercury even at low levels from industrial effluents and brine mud of chlor-alkali industry after pre-acid extraction. This makes it a highly efficient sorbent for possible application in effluent treatment. Model schemes for the removal and recovery of mercury from industrial effluents and municipal sewage (100-1000 litre) by a dynamic method are proposed and the costs incurred in a full-scale application method are indicated to show that the use of thio-foam could be commercially attractive. PMID:15091891

  3. Removal of elemental mercury by TiO2doped with WO3 and V2O5 for their photo- and thermo-catalytic removal mechanisms.

    PubMed

    Shen, Huazhen; Ie, Iau-Ren; Yuan, Chung-Shin; Hung, Chung-Hsuang; Chen, Wei-Hsiang

    2016-03-01

    The catalytic removal of Hg(0) was investigated to ascertain whether the catalysts could simultaneously possess both thermo- and photo-catalytic reactivity. The immobilized V2O5/TiO2 and WO3/TiO2 catalysts were synthesized by sol-gel method and then coated on the surface of glass beads for catalytic removal of Hg(0). They were also characterized by SEM, BET, XRD, UV-visible, and XPS analysis, and their catalytic reactivity was tested under 100-160 °C under the near-UV irradiation. The results indicated that V2O5/TiO2 solely possessed the thermo-catalytic reactivity while WO3/TiO2 only had photo-catalytic reactivity. Although the synthesis catalytic reactivity has not been found for these catalysts up to date, but compared with TiO2, the removal efficiencies of Hg(0) at 140 and 160 °C were enhanced; particularly, the efficiency was improved from 20 % at 160 °C by TiO2 to nearly 90 % by WO3/TiO2 under the same operating conditions. The effects of doping amount of V2O5 and WO3 were also investigated, and the results showed that 10 % V2O5 and 5 % WO3/TiO2 were the best immobilized catalysts for thermo- and photo-catalytic reactivity, respectively. The effect of different influent concentrations of Hg(0) was demonstrated that the highest concentration of Hg(0) led to the best removal efficiencies for V2O5/TiO2 and WO3/TiO2 at 140 and 160 °C, because high Hg(0) concentration increased the mass transfer rate of Hg(0) toward the surface of catalysts and drove the reaction to proceed. At last, the effect of single gas component on the removal of Hg(0) was also investigated. PMID:26590063

  4. Simultaneous removal of elemental mercury and NO from flue gas by V2O5-CeO2/TiO2 catalysts

    NASA Astrophysics Data System (ADS)

    Zhang, Xunan; Li, Caiting; Zhao, Lingkui; Zhang, Jie; Zeng, Guangming; Xie, Yin'e.; Yu, Ming'e.

    2015-08-01

    A series of Ce-doped V2O5/TiO2 catalysts synthesized by an ultrasound assisted impregnation method were employed to investigate simultaneous removal of elemental mercury (Hg0) and NO in lab-scale experiments. Scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), X-ray diffractogram (XRD), and X-ray photoelectron spectroscopy (XPS) analyses were used to characterize the samples. Compared to TiO2 support, the catalytic performance of CeO2 doped on both TiO2 and V2O5/TiO2 catalysts have been improved. Remarkably, 1%V2O5-10% CeO2/TiO2 (V1Ce10Ti) exhibited the highest Hg0 oxidation efficiency of 81.55% at 250 °C with a desired NO removal efficiency under the same condition. Both the NO conversion and Hg0 oxidation efficiency were enhanced in the presence of O2. The activity was inhibited by the injection of NH3 with the increase of NH3/NO. When in the presence of 400 ppm SO2, Hg0 oxidation was slightly affected. Furthermore, Hg0 removal behavior under both oxidation and selective catalytic reduction (SCR) condition over V1Ce10Ti were well investigated to further probe into the feasibility of one single unit for multi-pollutants control in industry application. The existence of the redox cycle of V4+ + Ce4+ ↔ V5+ + Ce3+ in V2O5-CeO2/TiO2 catalyst could not only greatly improve the NO conversion, but also promote the oxidation of Hg0.

  5. In situ stabilization of entrapped elemental mercury.

    PubMed

    Devasena, M; Nambi, Indumathi M

    2013-11-30

    Elemental mercury is a dense immiscible fluid which gets entrapped as residual mercury in the pore spaces of the subsurface during improper disposals and accidental spills. This paper investigates in situ stabilization of entrapped elemental mercury to mercury sulphide using aqueous sodium polysulphide solution. Batch experiments showed 100% conversion efficiency of elemental mercury to mercury sulphide in a period of 96 h with sodium polysulphide/elemental mercury molar ratio of 1. XRD analysis identified the precipitate formed as mercury sulphide. Micromodel experiments, with glass beads as porous media, further demonstrated in situ stabilization of entrapped mercury under different residual mercury saturations. It was found that in a period of 10 days, 10% of entrapped mercury was stabilized as mercury sulphide, 0.088% was removed as dissolved mercury and the remaining elemental mercury was retained in porous media encapsulated by the newly formed mercury sulphide precipitate. However, there was no leaching of mercury from the micromodel effluent once stabilization was achieved. PMID:24080327

  6. Study of the removal of mercury(II) and chromium(VI) from aqueous solutions by Moroccan stevensite.

    PubMed

    Benhammou, A; Yaacoubi, A; Nibou, L; Tanouti, B

    2005-01-31

    The objective of the present study was to investigate the adsorption of the heavy metals mercury(II) and chromium(VI), from aqueous solutions, onto Moroccan stevensite. A mineralogical and physicochemical characterization of natural stevensite was carried out. In order to improve the adsorption capacity of stevensite for Cr(VI), a preparation of stevensite was carried out. It consists in saturating the stevensite by ferrous iron Fe(II) and reducing the total Fe by Na(2)S(2)O(4). Then, the adsorption experiments were studied in batch reactors at 25+/-3 degrees C. The influence of the pH solution on the Cr(VI) and Hg(II) adsorption was studied in the pH range of 1.5-7.0. The optimum pH for the Cr(VI) adsorption is in the pH range of 2.0-5.0 while that of Hg(II) is at the pH values above 4.0. The adsorption kinetics were tested by a pseudo-second-order model. The adsorption rate of Hg(II) is 54.35 mmol kg(-1)min(-1) and that of Cr(VI) is 7.21 mmol kg(-1)min(-1). The adsorption equilibrium time for Hg(II) and Cr(VI) was reached within 2 and 12 h, respectively. The adsorption isotherms were described by the Dubinin-Radushkevich model. The maximal adsorption capacity for Cr(VI) increases from 13.7 (raw stevensite) to 48.86 mmol kg(-1) (modified stevensite) while that of Hg(II) decreases from 205.8 to 166.9 mmol kg(-1). The mechanism of Hg(II) and Cr(VI) adsorption was discussed. PMID:15629583

  7. Kinetics of mercury ions removal from synthetic aqueous solutions using by novel magnetic p(GMA-MMA-EGDMA) beads.

    PubMed

    Bayramoğlu, Gülay; Arica, M Yakup

    2007-06-01

    Poly(glycidylmethacrylate-methylmethacrylate), p(GMA-MMA-EGDMA), magnetic beads were prepared via suspension polymerization in the presence of ferric ions. The epoxy groups of the beads were converted into amino groups via ring opening reaction of the ammonia and, the aminated magnetic beads were used for the removal of Hg(II) ions from aqueous solution in a batch experiment and in a magnetically stabilized fluidized bed reactor (MFB). The magnetic p(GMA-MMA-EGDMA) beads were characterized with scanning electron microscope (SEM), FT-IR and ESR spectrophotometers. The optimum removal of Hg(II) ions was observed at pH 5.5. The maximum adsorption capacity of Hg(II) ions by using the magnetic beads was 124.8+/-2.1 mgg(-1) beads. In the continuous MFB reactor, Hg(II) ions adsorption capacity of the magnetic beads decreased with an increase in the flow-rate. The maximum adsorption capacity of the magnetic beads in the MFB reactor was 139.4+/-1.4 mgg(-1). The results indicate that the magnetic beads are promising for use in MFB for removal of Hg(II) ions from aqueous solution and/or waste water treatment. PMID:17118552

  8. Alkaline sorbent injection for mercury control

    DOEpatents

    Madden, Deborah A.; Holmes, Michael J.

    2002-01-01

    A mercury removal system for removing mercury from combustion flue gases is provided in which alkaline sorbents at generally extremely low stoichiometric molar ratios of alkaline earth or an alkali metal to sulfur of less than 1.0 are injected into a power plant system at one or more locations to remove at least between about 40% and 60% of the mercury content from combustion flue gases. Small amounts of alkaline sorbents are injected into the flue gas stream at a relatively low rate. A particulate filter is used to remove mercury-containing particles downstream of each injection point used in the power plant system.

  9. Alkaline sorbent injection for mercury control

    DOEpatents

    Madden, Deborah A.; Holmes, Michael J.

    2003-01-01

    A mercury removal system for removing mercury from combustion flue gases is provided in which alkaline sorbents at generally extremely low stoichiometric molar ratios of alkaline earth or an alkali metal to sulfur of less than 1.0 are injected into a power plant system at one or more locations to remove at least between about 40% and 60% of the mercury content from combustion flue gases. Small amounts of alkaline sorbents are injected into the flue gas stream at a relatively low rate. A particulate filter is used to remove mercury-containing particles downstream of each injection point used in the power plant system.

  10. Inorganic: the other mercury.

    PubMed

    Risher, John F; De Rosa, Christopher T

    2007-11-01

    There is a broad array of mercury species to which humans may be exposed. While exposure to methylmercury through fish consumption is widely recognized, the public is less aware of the sources and potential toxicity of inorganic forms of mercury. Some oral and laboratory thermometers, barometers, small batteries, thermostats, gas pressure regulators, light switches, dental amalgam fillings, cosmetic products, medications, cultural/religious practices, and gold mining all represent potential sources of exposure to inorganic forms of mercury. The route of exposure, the extent of absorption, the pharmacokinetics, and the effects all vary with the specific form of mercury and the magnitude and duration of exposure. If exposure is suspected, a number of tissue analyses can be conducted to confirm exposure or to determine whether an exposure might reasonably be expected to be biologically significant. By contrast with determination of exposure to methylmercury, for which hair and blood are credible indicators, urine is the preferred biological medium for the determination of exposure to inorganic mercury, including elemental mercury, with blood normally being of value only if exposure is ongoing. Although treatments are available to help rid the body of mercury in cases of extreme exposure, prevention of exposure will make such treatments unnecessary. Knowing the sources of mercury and avoiding unnecessary exposure are the prudent ways of preventing mercury intoxication. When exposure occurs, it should be kept in mind that not all unwanted exposures will result in adverse health consequences. In all cases, elimination of the source of exposure should be the first priority of public health officials. PMID:18044248

  11. Mercury Emission Measurement in Coal-Fired Boilers by Continuous Mercury Monitor and Ontario Hydro Method

    NASA Astrophysics Data System (ADS)

    Zhu, Yanqun; Zhou, Jinsong; He, Sheng; Cai, Xiaoshu; Hu, Changxin; Zheng, Jianming; Zhang, Le; Luo, Zhongyang; Cen, Kefa

    2007-06-01

    The mercury emission control approach attaches more importance. The accurate measurement of mercury speciation is a first step. Because OH method (accepted method) can't provide the real-time data and 2-week time for results attained, it's high time to seek on line mercury continuous emission monitors(Hg-CEM). Firstly, the gaseous elemental and oxidized mercury were conducted to measure using OH and CEM method under normal operation conditions of PC boiler after ESP, the results between two methods show good consistency. Secondly, through ESP, gaseous oxidized mercury decrease a little and particulate mercury reduce a little bit, but the elemental mercury is just the opposite. Besides, the WFGD system achieved to gaseous oxidized mercury removal of 53.4%, gaseous overall mercury and elemental mercury are 37.1% and 22.1%, respectively.

  12. Mercury and Your Health

    MedlinePlus

    ... the Risk of Exposure to Mercury Learn About Mercury What is Mercury What is Metallic mercury? Toxicological Profile ToxFAQs Mercury Resources CDC’s National Biomonitoring Program Factsheet on Mercury ...

  13. Planet Mercury

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Mariner 10's first image of Mercury acquired on March 24, 1974. During its flight, Mariner 10's trajectory brought it behind the lighted hemisphere of Mercury, where this image was taken, in order to acquire important measurements with other instruments.

    This picture was acquired from a distance of 3,340,000 miles (5,380,000 km) from the surface of Mercury. The diameter of Mercury (3,031 miles; 4,878 km) is about 1/3 that of Earth.

    Images of Mercury were acquired in two steps, an inbound leg (images acquired before passing into Mercury's shadow) and an outbound leg (after exiting from Mercury's shadow). More than 2300 useful images of Mercury were taken, both moderate resolution (3-20 km/pixel) color and high resolution (better than 1 km/pixel) black and white coverage.

  14. Planet Mercury

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Mariner 10's first image of Mercury acquired on March 24, 1974. During its flight, Mariner 10's trajectory brought it behind the lighted hemisphere of Mercury, where this image was taken, in order to acquire important measurements with other instruments. This picture was acquired from a distance of 3,340,000 miles (5,380,000 km) from the surface of Mercury. The diameter of Mercury (3,031 miles; 4,878 km) is about 1/3 that of Earth. Images of Mercury were acquired in two steps, an inbound leg (images acquired before passing into Mercury's shadow) and an outbound leg (after exiting from Mercury's shadow). More than 2300 useful images of Mercury were taken, both moderate resolution (3-20 km/pixel) color and high resolution (better than 1 km/pixel) black and white coverage.

  15. MULTIPOLLUTANT MERCURY AND ACID GASES CONTROL TECHNOLOGY

    EPA Science Inventory

    Plans are to continue testing for acid gas, mercury and NOx removal on baseline CFB operation with lime slurry, then use modified lime hydrates and slurries, and modified calcium silicates as additives for enhanced mercury and SO2 removal. Also, data from a coal-fired utility b...

  16. Advanced mercury removal from gold leachate solutions prior to gold and silver extraction: a field study from an active gold mine in Peru.

    PubMed

    Matlock, Matthew M; Howerton, Brock S; Van Aelstyn, Mike A; Nordstrom, Fredrik L; Atwood, David A

    2002-04-01

    Mercury contamination in the Gold-Cyanide Process (GCP) is a serious health and environmental problem. Following the heap leaching of gold and silver ores with NaCN solutions, portions of the mercury-cyano complexes often adhere to the activated carbon (AC) used to extract the gold. During the electrowinning and retorting steps, mercury can be (and often is) emitted to the air as a vapor. This poses a severe health hazard to plant workers and the local environment. Additional concerns relate to the safety of workers when handling the mercury-laden AC. Currently, mercury treatment from the heap leach solution is nonexistent. This is due to the fact that chelating ligands which can effectively work under the adverse pH conditions (as present in the heap leachate solutions) do not exist. In an effort to economically and effectively treat the leachate solution prior to passing over the AC, a dipotassium salt of 1,3-benzenediamidoethanethiol (BDET2-) has been developed to irreversibly bind and precipitate the mercury. The ligand has proven to be highly effective by selectively reducing mercury levels from average initial concentrations of 34.5 ppm (parts per million) to 0.014 ppm within 10 min and to 0.008 ppm within 15 min. X-ray powder diffraction (XRD), proton nuclear magnetic resonance (1H NMR), Raman, and infrared (IR) spectroscopy demonstrate the formation of a mercury-ligand compound, which remains insoluble over pH ranges of 0.0-14.0. Leachate samples from an active gold mine in Peru have been analyzed using cold vapor atomic fluorescence (CVAF) and inductively coupled plasma optical emission spectroscopy (ICP-OES) for metal concentrations before and after treatment with the BDET2- ligand. PMID:11999077

  17. Towards Elimination of the Dark-Rim Artifact in First-Pass Myocardial Perfusion MRI: Removing Gibbs Ringing Effects Using Optimized Radial Imaging

    PubMed Central

    Sharif, Behzad; Dharmakumar, Rohan; LaBounty, Troy; Arsanjani, Reza; Shufelt, Chrisandra; Thomson, Louise; Merz, C. Noel Bairey; Berman, Daniel S.; Li, Debiao

    2014-01-01

    Purpose Subendocardial dark-rim artifacts (DRAs) remain a major concern in first-pass perfusion (FPP) myocardial MRI and may lower the diagnostic accuracy for detection of ischemia. A major source of the DRA is known to be the “Gibbs ringing” effect. We propose an optimized radial acquisition strategy aimed at eliminating ringing-induced DRAs in FPP. Theory and Methods By studying the underlying point spread function (PSF), we show that optimized radial sampling with a simple reconstruction method can eliminate the oscillations in the PSF that cause ringing artifacts. We conduct realistic MRI phantom experiments and in-vivo studies (n=12 healthy humans) to study the artifact behavior of the proposed acquisition scheme in comparison to a conventional Cartesian protocol. Results Simulations and phantom experiments verify the theoretical expectations. Our in-vivo studies show that optimized radial imaging is capable of significantly reducing DRAs in the early myocardial enhancement phase (during which the ringing effect is most prominent and may obscure perfusion defects) while providing equivalent resolution and similar image quality as conventional Cartesian imaging. Conclusion The developed technical framework and results demonstrate that, compared to conventional Cartesian techniques, optimized radial imaging with the proposed optimizations significantly reduces the prevalence and spatial extent of DRAs in FPP imaging. PMID:24030840

  18. THE EFFECT OF MERCURY CONTROLS ON WALLBOARD MANUFACTURE

    SciTech Connect

    Sandra Meischen

    2004-07-01

    Pending EPA regulations may mandate 70 to 90% mercury removal efficiency from utility flue gas. A mercury control option is the trapping of oxidized mercury in wet flue gas desulfurization systems (FGD). The potential doubling of mercury in the FGD material and its effect on mercury volatility at temperatures common to wallboard manufacture is a concern that could limit the growing byproduct use of FGD material. Prediction of mercury fate is limited by lack of information on the mercury form in the FGD material. The parts per billion mercury concentrations prevent the identification of mercury compounds by common analytical methods. A sensitive analytical method, cold vapor atomic fluorescence, coupled with leaching and thermodecomposition methods were evaluated for their potential to identify mercury compounds in FGD material. The results of the study suggest that the mercury form is dominated by the calcium sulfate matrix and is probably associated with the sulfate form in the FGD material. Additionally, to determine the effect of high mercury concentration FGD material on wallboard manufacture, a laboratory FGD unit was built to trap the oxidized mercury generated in a simulated flue gas. Although the laboratory prepared FGD material did not contain the mercury concentrations anticipated, further thermal tests determined that mercury begins to evolve from FGD material at 380 to 390 F, consequently dropping the drying temperature should mitigate mercury evolution if necessary. Mercury evolution is also diminished as the weight of the wallboard sample increased. Consequently, mercury evolution may not be a significant problem in wallboard manufacture.

  19. Sulfur polymer stabilization/solidification (SPSS) treatment of mixed waste mercury recovered from environmental restoration activities at BNL

    SciTech Connect

    Kalb, P.; Adams, J.; Milian, L.

    2001-01-29

    Over 1,140 yd{sup 3} of radioactively contaminated soil containing toxic mercury (Hg) and several liters of mixed-waste elemental mercury were generated during a Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) removal action at Brookhaven National Laboratory (BNL). The US Department of Energy's (DOE) Office of Science and Technology Mixed Waste Focus Area (DOE MWFA) is sponsoring a comparison of several technologies that may be used to treat these wastes and similar wastes at BNL and other sites across the DOE complex. This report describes work conducted at BNL on the application and pilot-scale demonstration of the newly developed Sulfur Polymer Stabilization/Solidification (SPSS) process for treatment of contaminated mixed-waste soils containing high concentrations ({approximately} 5,000 mg/L) of mercury and liquid elemental mercury. BNL's SPSS (patent pending) process chemically stabilizes the mercury to reduce vapor pressure and leachability and physically encapsulates the waste in a solid matrix to eliminate dispersion and provide long-term durability. Two 55-gallon drums of mixed-waste soil containing high concentrations of mercury and about 62 kg of radioactive contaminated elemental mercury were successfully treated. Waste loadings of 60 wt% soil were achieved without resulting in any increase in waste volume, while elemental mercury was solidified at a waste loading of 33 wt% mercury. Toxicity Characteristic Leaching Procedure (TCLP) analyses indicate the final waste form products pass current Environmental Protection Agency (EPA) allowable TCLP concentrations as well as the more stringent proposed Universal Treatment Standards. Mass balance measurements show that 99.7% of the mercury treated was successfully retained within the waste form, while only 0.3% was captured in the off gas system.

  20. In-duct removal of mercury from coal-fired power plant flue gas by activated carbon: assessment of entrained flow versus wall surface contributions

    SciTech Connect

    Scala, F.; Chirone, R.; Lancia, A.

    2008-12-15

    In-duct mercury capture efficiency by activated carbon from coal-combustion flue gas was investigated. To this end, elemental mercury capture experiments were conducted at 100 C in a purposely designed 65-mm ID labscale pyrex apparatus operated as an entrained flow reactor. Gas residence times were varied between 0.7 and 2.0 s. Commercial-powdered activated carbon was continuously injected in the reactor and both mercury concentration and carbon elutriation rate were followed at the outlet. Transient mercury concentration profiles at the outlet showed that steady-state conditions were reached in a time interval of 15-20 min, much longer than the gas residence time in the reactor. Results indicate that the influence of the walls is non-negligible in determining the residence time of fine carbon particles in the adsorption zone, because of surface deposition and/or the establishment of a fluid-dynamic boundary layer near the walls. Total mercury capture efficiencies of 20-50% were obtained with carbon injection rates in the range 0.07-0.25 g/min. However, only a fraction of this capture was attributable to free-flowing carbon particles, a significant contribution coming from activated carbon staying near the reactor walls. Entrained bed experiments at lab-scale conditions are probably not properly representative of full-scale conditions, where the influence of wall interactions is lower. Moreover, previously reported entrained flow lab-scale mercury capture data should be reconsidered by taking into account the influence of particle-wall interactions.

  1. Mercury emissions control by wet FGD systems: EPRI pilot-scale results

    SciTech Connect

    Peterson, J.R.; Hargrove, O.W. Jr.; Seeger, D.M.

    1995-06-01

    This paper presents results from pilot-scale tests that investigated mercury removal across wet limestone flue gas desulfurization (FGD) systems. The program was conducted at EPRIs Environmental Control Technology Center, located in Barker, NY. The test results showed that mercuric chloride (HgCl{sub 2}) was efficiently removed across the FGD system, while elemental mercury was not collected. The practical implication of this study is that although FGD systems efficiently remove some forms of mercury from flue gas, the overall mercury removal efficiency, and therefore the total mercury emissions from a coal-fired power plant equipped with an FGD system, will depend on the chemical form of the mercury in the flue gas. Unfortunately, no validated gas sampling method is available for speciating the different forms of mercury in flue gas. It is, therefore, difficult to predict mercury removal across FGD systems and to interpret any mercury removal data that have been collected.

  2. Follow that mercury!

    SciTech Connect

    Linero, A.A.

    2008-07-01

    The article discusses one technology option for avoiding release of mercury captured by power plant pollution control equipment in order to render it usable in concrete. This is the use of selective catalytic reduction for NOx control and lime spray dryer absorbers (SDA) for SO{sub 2} control prior to particulate collection by fabric filters. In this scenario all mercury removed is trapped in the fabric filter baghouse. The US EPA did not establish mercury emission limits for existing cement plants in the latest regulation 40 CFR 63, Subpart LLL (December 2006) and was sued by the Portland Cement Association because of the Hg limits established for new kilns and by several states and environmental groups for the lack of limits on existing ones. A full version of this article is available on www.acaa-usa.org/AshatWork.htm. 2 figs.

  3. RECOVERY OF MERCURY FROM CONTAMINATED LIQUID WASTES

    SciTech Connect

    Robin M. Stewart

    1999-09-29

    Mercury was widely used in U.S. Department of Energy (DOE) weapons facilities, resulting in a broad range of mercury-contaminated wastes and wastewaters. Some of the mercury contamination has escaped to the local environment, particularly at the Y-12 Plant in Oak Ridge, Tennessee, where approximately 330 metric tons of mercury were discharged to the environment between 1953 and 1963 (TN & Associates, 1998). Effective removal of mercury contamination from water is a complex and difficult problem. In particular, mercury treatment of natural waters is difficult because of the low regulatory standards. For example, the Environmental Protection Agency has established a national ambient water quality standard of 12 parts-per-trillion (ppt), whereas the standard is 1.8 ppt in the Great Lakes Region. In addition, mercury in the environment is typically present in several different forms, but sorption processes are rarely effective with more than one or two of these forms. To meet the low regulatory discharge limits, an effective sorption process must be able to address all forms of mercury present in the water. One approach is to apply different sorbents in series depending on the mercury speciation and the regulatory discharge limits. ADA Technologies, Inc. has developed four new sorbents to address the variety of mercury species present in industrial discharges and natural waters. Three of these sorbents have been field tested on contaminated creek water at the Y-12 Plant. Two of these sorbents have been successfully demonstrated very high removal efficiencies for soluble mercury species, reducing mercury concentrations at the outlet of a pilot-scale system to less than 12 ppt for as long as six months. The other sorbent tested at the Y-12 Plant targeted colloidal mercury not removed by standard sorption or filtration processes. At the Y-12 Plant, colloidal mercury appears to be associated with iron, so a sorbent that removes mercury-iron complexes in the presence of a

  4. Efficiency of a cleanup technology to remove mercury from natural waters by means of rice husk biowaste: ecotoxicological and chemical approach.

    PubMed

    Rocha, Luciana S; Lopes, I; Lopes, Cláudia B; Henriques, Bruno; Soares, Amadeu M V M; Duarte, Armando C; Pereira, Eduarda

    2014-01-01

    In the present work, the efficiency of rice husk to remove Hg(II) from river waters spiked with realistic environmental concentrations of this metal (μg L(-1) range) was evaluated. The residual levels of Hg(II) obtained after the remediation process were compared with the guideline values for effluents discharges and water for human consumption, and the ecotoxicological effects using organisms of different trophic levels were assessed. The rice husk sorbent proved to be useful in decreasing Hg(II) contamination in river waters, by reducing the levels of Hg(II) to values of ca. 8.0 and 34 μg L(-1), for an Hg(II) initial concentration of 50 and 500 μg L(-1), respectively. The remediation process with rice husk biowaste was extremely efficient in river waters spiked with lower levels of Hg(II), being able to eliminate the toxicity to the exposed organisms algae Pseudokirchneriella subcapitata and rotifer Brachionus calyciflorus and ensure the total survival of Daphnia magna species. For concentrations of Hg(II) tenfold higher (500 μg L(-1)), the remediation process was not adequate in the detoxification process, still, the rice husk material was able to reduce considerably the toxicity to the bacteria Vibrio fischeri, algae P. subcapitata and rotifer B. calyciflorus, whose responses where fully inhibited during its exposure to the non-remediated river water. The use of a battery of bioassays with organisms from different trophic levels and whose sensitivity revealed to be different and dependent on the levels of Hg(II) contamination proved to be much more accurate in predicting the ecotoxicological hazard assessment of the detoxification process by means of rice husk biowaste. PMID:24671395

  5. Method for mercury refinement

    DOEpatents

    Grossman, Mark W.; Speer, Richard; George, William A.

    1991-01-01

    The effluent from mercury collected during the photochemical separation of the .sup.196 Hg isotope is often contaminated with particulate mercurous chloride, Hg.sub.2 Cl.sub.2. The use of mechanical filtering via thin glass tubes, ultrasonic rinsing with acetone (dimethyl ketone) and a specially designed cold trap have been found effective in removing the particulate (i.e., solid) Hg.sub.2 Cl.sub.2 contaminant. The present invention is particularly directed to such filtering.

  6. Method for mercury refinement

    DOEpatents

    Grossman, M.W.; Speer, R.; George, W.A.

    1991-04-09

    The effluent from mercury collected during the photochemical separation of the [sup 196]Hg isotope is often contaminated with particulate mercurous chloride, Hg[sub 2]Cl[sub 2]. The use of mechanical filtering via thin glass tubes, ultrasonic rinsing with acetone (dimethyl ketone) and a specially designed cold trap have been found effective in removing the particulate (i.e., solid) Hg[sub 2]Cl[sub 2] contaminant. The present invention is particularly directed to such filtering. 5 figures.

  7. Apparatus for mercury refinement

    DOEpatents

    Grossman, Mark W.; Speer, Richard; George, William A.

    1991-01-01

    The effluent from mercury collected during the photochemical separation of the .sup.196 Hg isotope is often contaminated with particulate mercurous chloride, Hg.sub.2 Cl.sub.2. The use of mechanical filtering via thin glass tubes, ultrasonic rinsing with acetone (dimethyl ketone) and a specially designed cold trap have been found effective in removing the particulate (i.e., solid) Hg.sub.2 Cl.sub.2 contaminant. The present invention is particularly directed to such filtering.

  8. Apparatus for mercury refinement

    DOEpatents

    Grossman, M.W.; Speer, R.; George, W.A.

    1991-07-16

    The effluent from mercury collected during the photochemical separation of the [sup 196]Hg isotope is often contaminated with particulate mercurous chloride, Hg[sub 2]Cl[sub 2]. The use of mechanical filtering via thin glass tubes, ultrasonic rinsing with acetone (dimethyl ketone) and a specially designed cold trap have been found effective in removing the particulate (i.e., solid) Hg[sub 2]Cl[sub 2] contaminant. The present invention is particularly directed to such filtering. 5 figures.

  9. Method for scavenging mercury

    SciTech Connect

    Chang, Shih-ger; Liu, Shou-heng; Liu, Zhao-rong; Yan, Naiqiang

    2009-01-20

    Disclosed herein is a method for removing mercury from a gas stream comprising contacting the gas stream with a getter composition comprising bromine, bromochloride, sulphur bromide, sulphur dichloride or sulphur monochloride and mixtures thereof. In one preferred embodiment the getter composition is adsorbed onto a sorbent. The sorbent may be selected from the group consisting of flyash, limestone, lime, calcium sulphate, calcium sulfite, activated carbon, charcoal, silicate, alumina and mixtures thereof. Preferred is flyash, activated carbon and silica.

  10. Method for scavenging mercury

    SciTech Connect

    Chang, Shih-ger; Liu, Shou-heng; Liu, Zhao-rong; Yan, Naiqiang

    2010-07-13

    Disclosed herein is a method for removing mercury from a gas stream comprising contacting the gas stream with a getter composition comprising bromine, bromochloride, sulphur bromide, sulphur dichloride or sulphur monochloride and mixtures thereof. In one preferred embodiment the getter composition is adsorbed onto a sorbent. The sorbent may be selected from the group consisting flyash, limestone, lime, calcium sulphate, calcium sulfite, activated carbon, charcoal, silicate, alumina and mixtures thereof. Preferred is flyash, activated carbon and silica.

  11. Method for scavenging mercury

    DOEpatents

    Chang, Shih-Ger; Liu, Shou-Heng; Liu, Zhao-Rong; Yan, Naiqiang

    2011-08-30

    Disclosed herein is a method for removing mercury from a gas stream comprising contacting the gas stream with a getter composition comprising bromine, bromochloride, sulphur bromide, sulphur dichloride or sulphur monochloride and mixtures thereof. In one preferred embodiment the getter composition is adsorbed onto a sorbent. The sorbent may be selected from the group consisting of flyash, limestone, lime, calcium sulphate, calcium sulfite, activated carbon, charcoal, silicate, alumina and mixtures thereof. Preferred is flyash, activated carbon and silica.

  12. MERCURY STABILITY IN THE ENVIRONMENT

    SciTech Connect

    John H. Pavlish

    1999-07-01

    The 1990 Clean Air Act Amendments (CAAAs) require the U.S. Environmental Protection Agency (EPA) to determine whether the presence of mercury and 188 other trace substances, referred to as air toxics or hazardous air pollutants (HAPs), in the stack emissions from fossil fuel-fired electric utility power plants poses an unacceptable public health risk (1). The EPA's conclusions and recommendations were presented in two reports: Mercury Study Report to Congress and Study of Hazardous Air Pollutant Emissions from Electric Utility Steam Generating Units-Final Report to Congress. The first congressional report addressed both human health and the environmental effects of anthropogenic mercury emissions, while the second report addressed the risk to public health posed by emissions of HAPs from steam electricity-generating units. The National Institute of Environmental Health Sciences is also required by the CAAAs to investigate mercury and determine a safe threshold level of exposure. Recently the National Academy of Sciences has also been commissioned by Congress to complete a report, based the available scientific evidence, regarding safe threshold levels of mercury exposure. Although the EPA reports did not state that mercury controls on coal-fired electric power stations should be required given the current state of the art, they did indicate that EPA views mercury as a potential threat to human health. It is likely that major sources of mercury emissions, including fossil-fired combustion systems, will be controlled at some point. In fact, municipal waste combustion units are already regulated. In anticipation of additional control measures, much research has been done (and continues) regarding the development of control technologies for mercury emitted from stationary sources to the atmosphere. Most approaches taken to date involve sorbent injection technologies or improve upon removal of mercury using existing technologies such as flue gas desulfurization

  13. Control of mercury pollution.

    PubMed

    Noyes, O R; Hamdy, M K; Muse, L A

    1976-01-01

    When a 203Ng(NO3)2 solution was kept at 25 degrees C in glass or polypropylene containers, 50 and 80% of original radioactivity was adsorbed to the containers' walls after 1 and 4 days, respectively. However, no loss in radioactivity was observed if the solution was supplemented with HgCl as carrier (100 mug Hg2+/ml) and stored in either container for 13 days. When 203Hg2+ was dissolved in glucose basal salt broth with added carrier, levels of 203Hg2+ in solution (kept in glass) decreased to 80 and 70% of original after 1 and 5 days and decreased even more if stored in polypropylene (60 and 40% of original activity after 1 and 4 days, respectively). In the absence of carrier, decreases of 203Hg2+ activities in media stored in either container were more pronounced due to chemisorption (but) not diffusion. The following factors affecting the removal of mercurials from aqueous solution stored in glass were examined: type and concentration of adsorbent (fiber glass and rubber powder); pH; pretreatment of the rubber; and the form of mercury used. Rubber was equally effective in the adsorption of organic and inorganic mercury. The pH of the aqueous 203Hg2+ solution was not a critical factor in the rate of adsorption of mercury by the rubber. In addition, the effect of soaking the rubber in water for 18 hr did not show any statistical difference when compared with nontreated rubber. It can be concluded that rubber is a very effective adsorbent of mercury and, thus, can be used as a simple method for control of mercury pollution. PMID:1549

  14. SELECTIVE CATALYTIC REDUCTION MERCURY FIELD SAMPLING PROJECT

    EPA Science Inventory

    The report details an investigation on the effect of selective catalytic reduction (SCR), selective noncatalytic reduction (SNCR), and flue gas conditioning on the speciation and removal of mercury at power plants. If SCR and/or SNCR systems enhance mercury conversion/capture, t...

  15. Impact of Sulfur Oxides on Mercury Capture by Activated Carbon

    SciTech Connect

    Presto, A.A.; Granite, E.J.

    2007-09-15

    Recent field tests of mercury removal with activated carbon injection (ACI) have revealed that mercury capture is limited in flue gases containing high concentrations of sulfur oxides (SOx). In order to gain a more complete understanding of the impact of SOx on ACI, mercury capture was tested under varying conditions of SO2 and SO3 concentrations using a packed bed reactor and simulated flue gas (SFG). The final mercury content of the activated carbons is independent of the SO2 concentration in the SFG, but the presence of SO3 inhibits mercury capture even at the lowest concentration tested (20 ppm). The mercury removal capacity decreases as the sulfur content of the used activated carbons increases from 1 to 10%. In one extreme case, an activated carbon with 10% sulfur, prepared by H2SO4 impregnation, shows almost no mercury capacity. The results suggest that mercury and sulfur oxides are in competition for the same binding sites on the carbon surface.

  16. Method for high temperature mercury capture from gas streams

    DOEpatents

    Granite, Evan J.; Pennline, Henry W.

    2006-04-25

    A process to facilitate mercury extraction from high temperature flue/fuel gas via the use of metal sorbents which capture mercury at ambient and high temperatures. The spent sorbents can be regenerated after exposure to mercury. The metal sorbents can be used as pure metals (or combinations of metals) or dispersed on an inert support to increase surface area per gram of metal sorbent. Iridium and ruthenium are effective for mercury removal from flue and smelter gases. Palladium and platinum are effective for mercury removal from fuel gas (syngas). An iridium-platinum alloy is suitable for metal capture in many industrial effluent gas streams including highly corrosive gas streams.

  17. Mercury's sodium exosphere

    NASA Astrophysics Data System (ADS)

    Schmidt, Carl A.

    In this dissertation I examine the properties and origins of the most energetic component of Mercury's atmosphere and how it couples to the planet's magnetosphere and space environment. Mercury' s atmosphere consists of particles liberated from its surface that follow ballistic, collisionless trajectories under the influence of gravity and solar radiation pressure. This tenuous atmosphere can be classified as an exosphere where the exobase boundary is the planet's surface. To explain how this exosphere is sustained, a number of theories have been presented: (1) thermal evaporation from the hot surface; (2) photo-desorption of surface materials by UV solar radiation; (3) sputtering by plasma surface interactions; and (4) vaporization of the surface by micro-meteorite impacts. Using a 3-dimensional numerical model, I determine the role each source has in populating the exosphere. New observations of Mercury's escaping atmosphere are presented using novel imaging techniques in which sodium acts as a tracer to identify atmospheric sources. I discuss the implications of these measurements for our understanding of the physical processes at work in the exosphere, and provide a foundation for modeling such processes. For the first time, this work quantifies the variability in the loss of Mercury's sodium as a seasonal effect. My observations show that atmospheric escape can, at times, exceed 1024 Na atoms/s, nearly twice the highest rate previously reported. By forward modeling Mercury' s atmospheric escape, I place new constraints on the source properties and eliminate the prevailing theory that the escaping tail is sputtered from the surface by solar wind ions. The MESSENGER spacecraft has recently discovered that sodium is distributed unevenly over the surface and that the magnetosphere is offset from the planet's center. Using the first model to include these effects, I demonstrate the magnetosphere's influence upon exospheric sources by simulating asymmetries observed

  18. Development of New Optical Sensors for Measurements of Mercury Concentrations, Speciation, and Chemistry

    SciTech Connect

    Robert Lucht

    2008-09-28

    A diode-laser-based ultraviolet absorption sensor for elemental mercury was developed and applied for measurements in a high-temperature flow reactor and in the exhaust stream of a coal-fired combustor. The final version of the sensor incorporates a 375-nm single-mode laser and a 784-nm distributed feedback (DFB) laser. The output of these lasers is sum-frequency mixed in a non-linear beta-barium borate crystal to generate a 254-nm beam. By tuning the frequency of the DFB laser, the ultraviolet beam frequency is tuned across the transition frequency of mercury at 253.7-nm. The tuning range is large enough that an off-resonant baseline was clearly visible on both sides of the Hg transition. Because of this large tuning range, the effects of broadband absorption can be effectively eliminated during data analysis. Broadband absorption is a major concern for lamp-based mercury sensor, and the sample to be monitored must be chemically treated prior to analysis to remove species such as SO{sub 2} that absorb near 253.7 nm. No pretreatment is required when our diode-laser-based sensor is used for elemental mercury measurements. Our laser sensor measurements were compared to measurements from a commercial mercury analyzer (CMA), and were generally in good agreement except that the insitu diode-laser-based sensor measurements tended to give somewhat higher concentrations than the CMA measurements, presumably due to absorption of elemental mercury in the sampling lines needed for the CMA measurements. At Texas A&M University, the homogeneous oxidation of elemental mercury was studied using a high-temperature flow reactor.

  19. Identification of elemental mercury in the subsurface

    DOEpatents

    Jackson, Dennis G

    2015-01-06

    An apparatus and process is provided for detecting elemental mercury in soil. A sacrificial electrode of aluminum is inserted below ground to a desired location using direct-push/cone-penetrometer based equipment. The insertion process removes any oxides or previously found mercury from the electrode surface. Any mercury present adjacent the electrode can be detected using a voltmeter which indicates the presence or absence of mercury. Upon repositioning the electrode within the soil, a fresh surface of the aluminum electrode is created allowing additional new measurements.

  20. Mercury sorbent delivery system for flue gas

    DOEpatents

    Klunder; ,Edgar B.

    2009-02-24

    The invention presents a device for the removal of elemental mercury from flue gas streams utilizing a layer of activated carbon particles contained within the filter fabric of a filter bag for use in a flue gas scrubbing system.

  1. Analysis of Alternative Mercury Control Strategies

    EIA Publications

    2005-01-01

    This analysis responds to a September 14, 2004, request from Chairmen James M. Inhofe and George V. Voinovich asking the Energy Information Administration (EIA) to analyze the impacts of different approaches for removing mercury from coal-fired power plants.

  2. A microscaled mercury saturation assay for metallothionein in fish.

    PubMed

    Shaw-Allen, Patricia; Elliott, Muriel; Jagoe, Charles H

    2003-09-01

    A mercury (Hg) saturation assay for measuring metallothionein (MT) in fish liver was modified by optimizing binding conditions to minimize the mercury and tissue consumed. The revised method uses stable Hg at low concentrations instead of 203Hg. At the reduced Hg concentrations used, MT concentrations in livers homogenized in saline appeared to increase systematically with dilution in both bluegill sunfish (Lepomis macrochirus) and largemouth bass (Micropterus salmoides). This error suggested a binding limitation due to sulfhydryl oxidation or competition for and removal of mercury by non-MT proteins. Homogenizing tissues in trichloroacetic acid (TCA) eliminated the interference. To further evaluate the method, the protocol was tested in the laboratory and field. Metallothionein in bluegill injected with 0.6 mg/kg zinc chloride increased at a rate of 0.03 nmole MT/g liver/h (r2 = 0.53, p = 0.001). Linearity improved when data were corrected for protein content (r2 = 0.74, p < 0.0001). Metallothionein levels in bluegill from a coal ash-contaminated environment were significantly increased over that of hatchery-reared sunfish (F = 20.17, p = 0.0003). The microscaled procedure minimizes concerns related to radioisotope use and waste generation while retaining the high sensitivity of the 203Hg assay. PMID:12959524

  3. Mercury CEM Calibration

    SciTech Connect

    John Schabron; Joseph Rovani; Mark Sanderson

    2008-02-29

    outputs of mercury generators are compared to one another using a nesting procedure which allows direct comparison of one generator with another and eliminates analyzer variability effects. The qualification portion of the EPA interim traceability protocol requires the vendors to define generator performance as affected by variables such as pressure, temperature, line voltage, and shipping. WRI is focusing efforts to determine actual generator performance related to the variables defined in the qualification portion of the interim protocol. The protocol will then be further revised by EPA based on what can actually be achieved with the generators. Another focus of the study is to evaluate approaches for field verification of generator performance. Upcoming work includes evaluation of oxidized mercury calibration generators, for which a separate protocol will be prepared by EPA. In addition, the variability of the spectrometers/analyzers under various environmental conditions needs to be defined and understood better. A main objective of the current work is to provide data on the performance and capabilities of elemental mercury generator/calibration systems for the development of realistic NIST traceability protocols for mercury vapor standards for continuous emission CEM calibration. This work is providing a direct contribution to the enablement of continuous emissions monitoring at coal-fired power plants in conformance with the CAMR. EPA Specification 12 states that mercury CEMs must be calibrated with NIST-traceable standards (Federal Register 2005). The initial draft of an elemental mercury generator traceability protocol was circulated by EPA in May 2007 for comment, and an interim protocol was issued in August 2007 (EPA 2007). Initially it was assumed that the calibration and implementation of mercury CEMs would be relatively simple, and implementation would follow the implementation of the Clean Air Interstate Rule (CAIR) SO{sub 2} and NO{sub x} monitoring, and

  4. Mercury speciation during in situ thermal desorption in soil.

    PubMed

    Park, Chang Min; Katz, Lynn E; Liljestrand, Howard M

    2015-12-30

    Metallic mercury (Hg(0)) and its compounds are highly mobile and toxic environmental pollutants at trace level. In situ thermal desorption (ISTD) is one of the soil remediation processes applying heat and vacuum simultaneously. Knowledge of thermodynamic mercury speciation is imperative to understand the fate and transport of mercury during thermal remediation and operate the treatment processes in a cost-effective manner. Hence, speciation model for inorganic mercury was developed over a range of environmental conditions to identify distribution of dissolved mercury species and potential transformations of mercury at near source environment. Simulation of phase transitions for metallic mercury, mercury(II) chloride and mercury sulfide with temperature increase showed that complete vaporization of metallic mercury and mercury(II) chloride were achieved below the boiling point of water. The effect of soil compositions on mercury removal was also evaluated to better understand thermal remediation process. Higher vapor pressures expected both from soil pore water and inorganic carbonate minerals in soil as well as creation of permeability were significant for complete vaporization and removal of mercury. PMID:26275352

  5. Chemical oxygen demand analysis of wastewater using trivalent manganese oxidant with chloride removal by sodium bismuthate pretreatment.

    PubMed

    Miller, D G; Brayton, S V; Boyles, W T

    2001-01-01

    Current chemical oxygen demand (COD) analyses generate wastes containing hexavalent and trivalent chromium, mercury, and silver. Waste disposal is difficult, expensive, and poses environmental hazards. A new COD test is proposed that eliminates these metals and shortens analysis time, where trivalent manganese oxidant replaces hexavalent chromium (dichromate). A silver catalyst is not required. Optional pretreatment removes chloride via oxidation to chlorine using sodium bismuthate, eliminating the need for mercury. Sample aqueous and solid components are separated for chloride removal, then recombined for total COD measurement. Soluble and nonsoluble COD can be determined separately. Digestion at 150 degrees C is complete in 1 hour. Results are determined by titration or by spectrophotometric reading. Test wastes contain none of the metals regulated for disposal under the Resource Conservation and Recovery Act. Results are shown for selected organic compounds and various wastewaters. Statistical comparisons are made with dichromate COD and biochemical oxygen demand (BOD5) test values. PMID:11558305

  6. Absorption characteristics of elemental mercury in mercury chloride solutions.

    PubMed

    Ma, Yongpeng; Xu, Haomiao; Qu, Zan; Yan, Naiqiang; Wang, Wenhua

    2014-11-01

    Elemental mercury (Hg(0)) in flue gases can be efficiently captured by mercury chloride (HgCl2) solution. However, the absorption behaviors and the influencing effects are still poorly understood. The mechanism of Hg(0) absorption by HgCl2 and the factors that control the removal were studied in this paper. It was found that when the mole ratio of Cl(-) to HgCl2 is 10:1, the Hg(0) removal efficiency is the highest. Among the main mercury chloride species, HgCl3(-) is the most efficient ion for Hg(0) removal in the HgCl2 absorption system when moderate concentrations of chloride ions exist. The Hg(0) absorption reactions in the aqueous phase were investigated computationally using Moller-Plesset perturbation theory. The calculated Gibbs free energies and energy barriers are in excellent agreement with the results obtained from experiments. In the presence of SO3(2-) and SO2, Hg(2+) reduction occurred and Hg(0) removal efficiency decreased. The reduced Hg(0) removal can be controlled through increased chloride concentration to some degree. Low pH value in HgCl2 solution enhanced the Hg(0) removal efficiency, and the effect was more significant in dilute HgCl2 solutions. The presence of SO4(2-) and NO3(-) did not affect Hg(0) removal by HgCl2. PMID:25458680

  7. Mercury Control with Calcium-Based Sorbents and Oxidizing Agents

    SciTech Connect

    Thomas K. Gale

    2005-07-01

    This Final Report contains the test descriptions, results, analysis, correlations, theoretical descriptions, and model derivations produced from many different investigations performed on a project funded by the U.S. Department of Energy, to investigate calcium-based sorbents and injection of oxidizing agents for the removal of mercury. Among the technologies were (a) calcium-based sorbents in general, (b) oxidant-additive sorbents developed originally at the EPA, and (c) optimized calcium/carbon synergism for mercury-removal enhancement. In addition, (d) sodium-tetrasulfide injection was found to effectively capture both forms of mercury across baghouses and ESPs, and has since been demonstrated at a slipstream treating PRB coal. It has been shown that sodium-tetrasulfide had little impact on the foam index of PRB flyash, which may indicate that sodium-tetrasulfide injection could be used at power plants without affecting flyash sales. Another technology, (e) coal blending, was shown to be an effective means of increasing mercury removal, by optimizing the concentration of calcium and carbon in the flyash. In addition to the investigation and validation of multiple mercury-control technologies (a through e above), important fundamental mechanism governing mercury kinetics in flue gas were elucidated. For example, it was shown, for the range of chlorine and unburned-carbon (UBC) concentrations in coal-fired utilities, that chlorine has much less effect on mercury oxidation and removal than UBC in the flyash. Unburned carbon enhances mercury oxidation in the flue gas by reacting with HCl to form chlorinated-carbon sites, which then react with elemental mercury to form mercuric chloride, which subsequently desorbs back into the flue gas. Calcium was found to enhance mercury removal by stabilizing the oxidized mercury formed on carbon surfaces. Finally, a model was developed to describe these mercury adsorption, desorption, oxidation, and removal mechanisms, including

  8. Mercury concentration in coal - Unraveling the puzzle

    USGS Publications Warehouse

    Toole-O'Neil, B.; Tewalt, S.J.; Finkelman, R.B.; Akers, D.J.

    1999-01-01

    Based on data from the US Geological Survey's COALQUAL database, the mean concentration of mercury in coal is approximately 0.2 ??gg-1. Assuming the database reflects in-ground US coal resources, values for conterminous US coal areas range from 0.08 ??gg-1 for coal in the San Juan and Uinta regions to 0.22 ??gg-1 for the Gulf Coast lignites. Recalculating the COALQUAL data to an equal energy basis unadjusted for moisture differences, the Gulf Coast lignites have the highest values (36.4 lb of Hg/1012 Btu) and the Hams Fork region coal has the lowest value (4.8 lb of Hg/1012Btu). Strong indirect geochemical evidence indicates that a substantial proportion of the mercury in coal is associated with pyrite occurrence. This association of mercury and pyrite probably accounts for the removal of mercury with the pyrite by physical coal cleaning procedures. Data from the literature indicate that conventional coal cleaning removes approximately 37% of the mercury on an equal energy basis, with a range of 0% to 78%. When the average mercury reduction value is applied to in-ground mercury values from the COALQUAL database, the resulting 'cleaned' mercury values are very close to mercury in 'as-shipped' coal from the same coal bed in the same county. Applying the reduction fact or for coal cleaning to eastern US bituminous coal, reduces the mercury input load compared to lower-rank non-deaned western US coal. In the absence of analytical data on as-shipped coal, the mercury data in the COALQUAL database, adjusted for deanability where appropriate, may be used as an estimator of mercury contents of as-shipped coal. ?? 1998 Published by Elsevier Science Ltd. All rights reserved.

  9. Characteristics of mercury cycling in the cement production process.

    PubMed

    Wang, Fengyang; Wang, Shuxiao; Zhang, Lei; Yang, Hai; Wu, Qingru; Hao, Jiming

    2016-01-25

    The mercury cycling caused by dust shuttling significantly increases the atmospheric emissions from cement production. A comprehensive understanding of this mercury cycling can promote the development of mercury emission control technologies. In this study, the characteristics of mercury cycling in the cement production process were first investigated. Furthermore, the mercury enrichment and effects of dust treatment were evaluated based on the field tests conducted in two Chinese cement plants. The mercury cycling between the kiln system and the raw mill system was the most important aspect and contributed 57-73% to the total amount of mercury emitted from the kiln system. Mercury emitted from the kiln system with flue gas was enriched as high as 3.4-8.8 times in the two tested plants compared to the amount of mercury in the raw materials and coal due to mercury cycling. The mercury enrichment can be significantly affected by the proportion of mercury cycled back to the kiln system. The effects of dust treatment were evaluated, and dust treatment can efficiently reduce approximately 31-70% of atmospheric mercury emissions in the two plants. The reduction proportion approximately linearly decreased with the proportion of mercury removed from the collected dust. PMID:26448491

  10. Aqueous mercury adsorption by activated carbons.

    PubMed

    Hadi, Pejman; To, Ming-Ho; Hui, Chi-Wai; Lin, Carol Sze Ki; McKay, Gordon

    2015-04-15

    Due to serious public health threats resulting from mercury pollution and its rapid distribution in our food chain through the contamination of water bodies, stringent regulations have been enacted on mercury-laden wastewater discharge. Activated carbons have been widely used in the removal of mercuric ions from aqueous effluents. The surface and textural characteristics of activated carbons are the two decisive factors in their efficiency in mercury removal from wastewater. Herein, the structural properties and binding affinity of mercuric ions from effluents have been presented. Also, specific attention has been directed to the effect of sulfur-containing functional moieties on enhancing the mercury adsorption. It has been demonstrated that surface area, pore size, pore size distribution and surface functional groups should collectively be taken into consideration in designing the optimal mercury removal process. Moreover, the mercury adsorption mechanism has been addressed using equilibrium adsorption isotherm, thermodynamic and kinetic studies. Further recommendations have been proposed with the aim of increasing the mercury removal efficiency using carbon activation processes with lower energy input, while achieving similar or even higher efficiencies. PMID:25644627

  11. Phased array ghost elimination.

    PubMed

    Kellman, Peter; McVeigh, Elliot R

    2006-05-01

    Parallel imaging may be applied to cancel ghosts caused by a variety of distortion mechanisms, including distortions such as off-resonance or local flow, which are space variant. Phased array combining coefficients may be calculated that null ghost artifacts at known locations based on a constrained optimization, which optimizes SNR subject to the nulling constraint. The resultant phased array ghost elimination (PAGE) technique is similar to the method known as sensitivity encoding (SENSE) used for accelerated imaging; however, in this formulation is applied to full field-of-view (FOV) images. The phased array method for ghost elimination may result in greater flexibility in designing acquisition strategies. For example, in multi-shot EPI applications ghosts are typically mitigated by the use of an interleaved phase encode acquisition order. An alternative strategy is to use a sequential, non-interleaved phase encode order and cancel the resultant ghosts using PAGE parallel imaging. Cancellation of ghosts by means of phased array processing makes sequential, non-interleaved phase encode acquisition order practical, and permits a reduction in repetition time, TR, by eliminating the need for echo-shifting. Sequential, non-interleaved phase encode order has benefits of reduced distortion due to off-resonance, in-plane flow and EPI delay misalignment. Furthermore, the use of EPI with PAGE has inherent fat-water separation and has been used to provide off-resonance correction using a technique referred to as lipid elimination with an echo-shifting N/2-ghost acquisition (LEENA), and may further generalized using the multi-point Dixon method. Other applications of PAGE include cancelling ghosts which arise due to amplitude or phase variation during the approach to steady state. Parallel imaging requires estimates of the complex coil sensitivities. In vivo estimates may be derived by temporally varying the phase encode ordering to obtain a full k-space dataset in a scheme

  12. NOVEL MERCURY OXIDANT AND SORBENT FOR MERCURY EMISSIONS CONTROL FROM COAL-FIRED POWER PLANTS

    EPA Science Inventory

    The authors have successfully developed novel efficient and cost-effective sorbent and oxidant for removing mercury from power plant flue gases. These sorbent and oxidant offer great promise for controlling mercury emissions from coal-fired power plants burning a wide range of c...

  13. Mercury emissions from municipal solid waste combustors

    SciTech Connect

    Not Available

    1993-05-01

    This report examines emissions of mercury (Hg) from municipal solid waste (MSW) combustion in the United States (US). It is projected that total annual nationwide MSW combustor emissions of mercury could decrease from about 97 tonnes (1989 baseline uncontrolled emissions) to less than about 4 tonnes in the year 2000. This represents approximately a 95 percent reduction in the amount of mercury emitted from combusted MSW compared to the 1989 mercury emissions baseline. The likelihood that routinely achievable mercury emissions removal efficiencies of about 80 percent or more can be assured; it is estimated that MSW combustors in the US could prove to be a comparatively minor source of mercury emissions after about 1995. This forecast assumes that diligent measures to control mercury emissions, such as via use of supplemental control technologies (e.g., carbon adsorption), are generally employed at that time. However, no present consensus was found that such emissions control measures can be implemented industry-wide in the US within this time frame. Although the availability of technology is apparently not a limiting factor, practical implementation of necessary control technology may be limited by administrative constraints and other considerations (e.g., planning, budgeting, regulatory compliance requirements, etc.). These projections assume that: (a) about 80 percent mercury emissions reduction control efficiency is achieved with air pollution control equipment likely to be employed by that time; (b) most cylinder-shaped mercury-zinc (CSMZ) batteries used in hospital applications can be prevented from being disposed into the MSW stream or are replaced with alternative batteries that do not contain mercury; and (c) either the amount of mercury used in fluorescent lamps is decreased to an industry-wide average of about 27 milligrams of mercury per lamp or extensive diversion from the MSW stream of fluorescent lamps that contain mercury is accomplished.

  14. Activated carbon injection - a mercury control success story

    SciTech Connect

    2008-07-01

    Almost 100 full-scale activated carbon injection (ACI) systems have been ordered by US electric utilities. These systems have the potential to remove over 90% of the mercury in flue, at a cost below $10,000 per pound of mercury removal. Field trials of ACI systems arm outlined. 1 fig.

  15. The control of mercury vapor using biotrickling filters.

    PubMed

    Philip, Ligy; Deshusses, Marc A

    2008-01-01

    The feasibility of using biotrickling filters for the removal of mercury vapor from simulated flue gases was evaluated. The experiments were carried out in laboratory-scale biotrickling filters with various mixed cultures naturally attached on a polyurethane foam packing. Sulfur oxidizing bacteria, toluene degraders and denitrifiers were used and compared for their ability to remove Hg 0 vapor. In particular, the biotrickling filters with sulfur oxidizing bacteria were able to remove 100% of mercury vapor, with an inlet concentration of 300-650 microg m(-3), at a gas contact time as low as six seconds. 87-92% of the removed mercury was fixed in or onto the microbial cells while the remaining left the system with the trickling liquid. The removal of mercury vapors in a biotrickling filter with dead cells was almost equivalent to this in biotrickling filters with live cells, indicating that significant abiotic removal mechanisms existed. Sulfur oxidizing bacteria biotrickling filters were the most effective in controlling mercury vapors, suggesting that sulfur played a key role. Identification of the location of metal deposition and of the form of metal was conducted using TEM, energy dispersive X-ray analysis (EDAX) and mercury elution analyses. The results suggested that mercury removal was through a series of complex mechanisms, probably both biotic and abiotic, including sorption in and onto cellular material and possible biotransformations. Overall, the study demonstrates that biotrickling filters appear to be a promising alternative for mercury vapor removal from flue gases. PMID:17692357

  16. A simple mercury vapor detector for geochemical prospecting

    USGS Publications Warehouse

    Vaughn, William W.

    1967-01-01

    The detector utilizes a large-volume atomic-absorption technique for quantitative determinations of mercury vapor thermally released from crushed rock. A quartz-enclosed noble-metal amalgamative stage, which is temperature controlled and is actuated by a radio-frequency induction heater, selectively traps the mercury and eliminates low-level contamination. As little as 1 part per billion of mercury can be detected in a 1-gram sample in a 1-minute analytical period.

  17. Mercury Contamination

    PubMed Central

    Thompson, Marcella R.

    2013-01-01

    IN BRIEF A residential elemental mercury contamination incident in Rhode Island resulted in the evacuation of an entire apartment complex. To develop recommendations for improved response, all response-related documents were examined; personnel involved in the response were interviewed; policies and procedures were reviewed; and environmental monitoring data were compiled from specific phases of the response for analysis of effect. A significant challenge of responding to residential elemental mercury contamination lies in communicating risk to residents affected py a HazMat spill. An ongoing, open and honest dialogue is emphasized where concerns of the public are heard and addressed, particularly when establishing and/or modifying policies and procedures for responding to residential elemental mercury contamination. PMID:23436951

  18. THE IMPORTANCE OF EMISSIONS SPECIATION TO THE ATMOSPHERIC TRANSPORT AND DEPOSITION OF MERCURY

    EPA Science Inventory

    The atmospheric pathway of the global mercury cycle is believed to be the main source of mercury contamination to aquatic eco-systems throughout the United States and in most other nations where direct disposal of mercury to water has been largely eliminated. Although the spatia...

  19. Investigation of mercury thruster isolators

    NASA Technical Reports Server (NTRS)

    Mantenieks, M. A.

    1973-01-01

    Mercury ion thruster isolator lifetime tests were performed using different isolator materials and geometries. Tests were performed with and without the flow of mercury through the isolators in an oil diffusion pumped vacuum facility and cryogenically pumped bell jar. The onset of leakage current in isolators occurred in time intervals ranging from a few hours to many hundreds of hours. In all cases, surface contamination was responsible for the onset of leakage current and subsequent isolator failure. Rate of increase of leakage current and the leakage current level increased approximately exponentially with isolator temperature. Careful attention to shielding techniques and the elimination of sources of metal oxides appear to have eliminated isolator failures as a thruster life limiting mechanism.

  20. Accumulation of mercury in selected plant species grown in soils contaminated with different mercury compounds

    SciTech Connect

    Su, Yi; Han, Fengxiang; Shiyab, Safwan; Chen, Jian; Monts, David L.

    2007-07-01

    The objective of our research is to screen and search for suitable plant species for phyto-remediation of mercury-contaminated soil. Currently our effort is specifically focused on mercury removal from the U.S. Department of Energy (DOE) sites, where mercury contamination is a major concern. In order to cost effectively implement mercury remediation efforts, it is necessary now to obtain an improved understanding of biological means of removing mercury and mercury compounds.. Phyto-remediation is a technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. In particular, phyto-extraction is the uptake of contaminants by plant roots and translocation within the plants to shoots or leaves. Contaminants are generally removed by harvesting the plants. We have investigated phyto-extraction of mercury from contaminated soil by using some of the known metal-accumulating plants since no natural plant species with mercury hyper-accumulating properties has yet been identified. Different natural plant species have been studied for mercury uptake, accumulation, toxicity and overall mercury removal efficiency. Various mercury compounds, such as HgS, HgCl{sub 2}, and Hg(NO{sub 3}){sub 2}, were used as contaminant sources. Different types of soil were examined and chosen for phyto-remediation experiments. We have applied microscopy and diffuse reflectance spectrometry as well as conventional analytical chemistry to monitor the phyto-remediation processes of mercury uptake, translocation and accumulation, and the physiological impact of mercury contaminants on selected plant species. Our results indicate that certain plant species, such as beard grass (Polypogon monospeliensis), accumulated a very limited amount of mercury in the shoots (<65 mg/kg), even though root mercury accumulation is significant (maximum 2298 mg/kg). Consequently, this plant species may not be suitable for mercury phyto-remediation. Other plant species

  1. Advanced Gasification Mercury/Trace Metal Control with Monolith Traps

    SciTech Connect

    Michael L. Swanson; Grant E. Dunham; Mark A. Musich

    2007-02-01

    Three potential additives for controlling mercury emissions from syngas at temperatures ranging from 350 to 500 F (177 to 260 C) were developed. Current efforts are being directed at increasing the effective working temperature for these sorbents and also being able to either eliminate any potential mercury desorption or trying to engineer a trace metal removal system that can utilize the observed desorption process to repeatedly regenerate the same sorbent monolith for extended use. Project results also indicate that one of these same sorbents can also successfully be utilized for arsenic removal. Capture of the hydrogen selenide in the passivated tubing at elevated temperatures has resulted in limited results on the effective control of hydrogen selenide with these current sorbents, although lower-temperature results are promising. Preliminary economic analysis suggests that these Corning monoliths potentially could be more cost-effective than the conventional cold-gas (presulfided activated carbon beds) technology currently being utilized. Recent Hg-loading results might suggest that the annualized costs might be as high as 2.5 times the cost of the conventional technology. However, this annualized cost does not take into account the significantly improved thermal efficiency of any plant utilizing the warm-gas monolith technology currently being developed.

  2. Increased Mercury Bioaccumulation Follows Water Quality Improvement

    SciTech Connect

    Bogle, M.A.; Peterson, M.J.; Smith, J.G.; Southworth, G.R.

    1999-09-15

    Changes in physical and chemical characteristics of aquatic habitats made to reduce or eliminate ecological risks can sometimes have unforeseen consequences. Environmental management activities on the U.S. Dept. of Energy reservation in Oak Ridge, Tennessee,have succeeded in improving water quality in streams impacted by discharges fi-om industrial facilities and waste disposal sites. The diversity and abundance of pollution-sensitive components of the benthic macroinvertebrate communities of three streams improved after new waste treatment systems or remedial actions reduced inputs of various toxic chemicals. Two of the streams were known to be mercury-contaminated from historical spills and waste disposal practices. Waterborne mercury concentrations in the third were typical of uncontaminated systems. In each case, concentrations of mercury in fish, or the apparent biological availability of mercury increased over the period during which ecological metrics indicated improved water quality. In the system where waterborne mercury concentrations were at background levels, increased mercury bioaccumulation was probably a result of reduced aqueous selenium concentrations; however, the mechanisms for increased mercury accumulation in the other two streams remain under investigation. In each of the three systems, reduced inputs of metals and inorganic anions was followed by improvements in the health of aquatic invertebrate communities. However, this reduction in risk to aquatic invertebrates was accompanied by increased risk to humans and piscivorous wildlife related to increased mercury concentrations in fish.

  3. Formic Acid Free Flowsheet Development To Eliminate Catalytic Hydrogen Generation In The Defense Waste Processing

    SciTech Connect

    Lambert, Dan P.; Stone, Michael E.; Newell, J. David; Fellinger, Terri L.; Bricker, Jonathan M.

    2012-09-14

    The Defense Waste Processing Facility (DWPF) processes legacy nuclear waste generated at the Savannah River Site (SRS) during production of plutonium and tritium demanded by the Cold War. The nuclear waste is first treated via a complex sequence of controlled chemical reactions and then vitrified into a borosilicate glass form and poured into stainless steel canisters. Converting the nuclear waste into borosilicate glass canisters is a safe, effective way to reduce the volume of the waste and stabilize the radionuclides. Testing was initiated to determine whether the elimination of formic acid from the DWPF's chemical processing flowsheet would eliminate catalytic hydrogen generation. Historically, hydrogen is generated in chemical processing of alkaline High Level Waste sludge in DWPF. In current processing, sludge is combined with nitric and formic acid to neutralize the waste, reduce mercury and manganese, destroy nitrite, and modify (thin) the slurry rheology. The noble metal catalyzed formic acid decomposition produces hydrogen and carbon dioxide. Elimination of formic acid by replacement with glycolic acid has the potential to eliminate the production of catalytic hydrogen. Flowsheet testing was performed to develop the nitric-glycolic acid flowsheet as an alternative to the nitric-formic flowsheet currently being processed at the DWPF. This new flowsheet has shown that mercury can be reduced and removed by steam stripping in DWPF with no catalytic hydrogen generation. All processing objectives were also met, including greatly reducing the Slurry Mix Evaporator (SME) product yield stress as compared to the baseline nitric/formic flowsheet. Ten DWPF tests were performed with nonradioactive simulants designed to cover a broad compositional range. No hydrogen was generated in testing without formic acid.

  4. Mercury, elemental

    Integrated Risk Information System (IRIS)

    Mercury , elemental ; CASRN 7439 - 97 - 6 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcinoge

  5. Mercury's Messenger

    ERIC Educational Resources Information Center

    Chapman, Clark R.

    2004-01-01

    Forty years after Mariner 2, planetary exploration has still only just begun, and many more missions are on drawing boards, nearing the launch pad, or even en route across interplanetary space to their targets. One of the most challenging missions that will be conducted this decade is sending the MESSENGER spacecraft to orbit the planet Mercury.…

  6. Trophic transfer efficiency of mercury to lake whitefish Coregonus clupeaformis from its prey

    USGS Publications Warehouse

    Madenjian, C.P.; O'Connor, D.V.

    2008-01-01

    In the laboratory, net trophic transfer efficiency of mercury to lake whitefish Coregonus clupeaformis from its prey was estimated to be 63.5%. Assuming that gross trophic transfer efficiency of mercury to lake whitefish from its prey was equal to 80%, we estimated that the rate at which lake whitefish eliminated mercury was 0.000730 day-1. Our laboratory estimate of mercury elimination rate was 2.4 times lower than the value predicted by a published regression equation developed from previous studies on mercury elimination rates for fish. Thus, our results suggested that mercury elimination rates for fish have been overestimated in previous studies. ?? 2008 Springer Science+Business Media, LLC.

  7. Revealing Mercury

    NASA Astrophysics Data System (ADS)

    Prockter, L. M.; Solomon, S. C.; Head, J. W.; Watters, T. R.; Murchie, S. L.; Robinson, M. S.; Chapman, C. R.; McNutt, R. L.

    2009-04-01

    The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, developed under NASA's Discovery Program, launched in August 2004. En route to insertion into orbit about Mercury in 2011, MESSENGER flies by Mercury three times. The first and second of these encounters were accomplished in January and October of 2008. These flybys viewed portions of Mercury's surface that were not observed by Mariner 10 during its reconnaissance of somewhat less than half of the planet in 1974-1975. All MESSENGER instruments operated during each flyby and returned a wealth of new data. Many of the new observations were focused on the planet's geology, including monochrome imaging at resolutions as high as 100 m/pixel, multispectral imaging in 11 filters at resolutions as high as 500 m/pixel, laser altimetry tracks extending over several thousands of kilometers, and high-resolution spectral measurements of several types of terrain. Here we present an overview of the first inferences on the global geology of Mercury from the MESSENGER observations. Whereas evidence for volcanism was equivocal from Mariner 10 data, the new MESSENGER images and altimetry provide compelling evidence that volcanism was widespread and protracted on Mercury. Color imaging reveals three common spectral units on the surface: a higher-reflectance, relatively red material occurring as a distinct class of smooth plains, typically with distinct embayment relationships interpreted to indicate volcanic emplacement; a lower-reflectance, relatively blue material typically excavated by impact craters and therefore inferred to be more common at depth; and a spectrally intermediate terrain that constitutes much of the uppermost crust. Three more minor spectral units are also seen: fresh crater ejecta, reddish material associated with rimless depressions interpreted to be volcanic centers, and high-reflectance deposits seen in some crater floors. Preliminary measurements of crater size

  8. RECOVERY OF MERCURY FROM CONTAMINATED PRIMARY AND SECONDARY WASTES

    SciTech Connect

    A. Faucette; J. Bognar; T. Broderick; T. Battaglia

    2000-01-13

    Effective removal of mercury contamination from water is a complex and difficult problem. In particular, mercury treatment of natural waters is difficult because of the low regulatory standards. For example, the Environmental Protection Agency has established a national ambient water quality standard of 12 parts-per-trillion (ppt), whereas the standard is 1.8 ppt in the Great Lakes Region. In addition, mercury is typically present in several different forms, but sorption processes are rarely effective with more than one or two of these forms. To meet the low regulatory discharge limits, a sorption process must be able to address all forms of mercury present in the water. One approach is to apply different sorbents in series depending on the mercury speciation and the regulatory discharge limits. Four new sorbents have been developed to address the variety of mercury species present in industrial discharges and natural waters. Three of these sorbents have been field tested on contaminated creek water at the Y-12 Plant. Two of these sorbents have demonstrated very high removal efficiencies for soluble mercury species, with mercury concentrations at the outlet of a pilot-scale system less than 12 ppt for as long as six months. The other sorbent tested at the Y-12 Plant is targeted at colloidal mercury that is not removed by standard sorption or filtration processes. At the Y-12 Plant, colloidal mercury appears to be associated with iron, so a sorbent that removes mercury-iron complexes in the presence of a magnetic field was evaluated. Field results indicate good removal of this mercury fraction from the Y-12 waters. In addition, this sorbent is easily regenerated by simply removing the magnetic field and flushing the columns with water. The fourth sorbent is still undergoing laboratory development, but results to date indicate exceptionally high mercury sorption capacity. The sorbent is capable of removing all forms of mercury typically present in natural and

  9. Preparation of hybrid organic-inorganic mesoporous silicas applied to mercury removal from aqueous media: Influence of the synthesis route on adsorption capacity and efficiency.

    PubMed

    Pérez-Quintanilla, Damián; Sánchez, Alfredo; Sierra, Isabel

    2016-06-15

    New hybrid organic-inorganic mesoporous silicas were prepared by employing three different synthesis routes and mercury adsorption studies were done in aqueous media using the batch technique. The organic ligands employed for the functionalization were derivatives of 2-mercaptopyrimidine or 2-mercaptothiazoline, and the synthesis pathways used were post-synthesis, post-synthesis with surface ion-imprinting and co-condensation with ion-imprinting. The incorporation of functional groups and the presence of ordered mesopores in the organosilicas was confirmed by XRD, TEM and SEM, nitrogen adsorption-desorption isotherms, (13)C MAS-NMR, (29)Si MAS-NMR, elemental and thermogravimetric analysis. The highest adsorption capacity and selectivity observed was for the material functionalized with 2-mercaptothiazoline ligand by means the co-condensation with ion-imprinting route (1.03mmolg(-1) at pH 6). The prepared material could be potential sorbent for the extraction of this heavy metal from environmental and drinking waters. PMID:27023632

  10. Mercury(II) removal from aqueous solutions and wastewaters using a novel cation exchanger derived from coconut coir pith and its recovery.

    PubMed

    Anirudhan, T S; Divya, L; Ramachandran, M

    2008-09-15

    A new adsorbent (PGCP-COOH) having carboxylate functional group at the chain end was synthesized by grafting poly(hydroxyethylmethacrylate) onto coconut coir pith, CP (a coir industry-based lignocellulosic residue), using potassium peroxydisulphate as an initiator and in the presence of N,N'-methylenebisacrylamide as a cross-linking agent. The adsorbent was characterized with the help of infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy, and potentiometric titrations. The ability of PGCP-COOH to remove Hg(II) from aqueous solutions was assessed using batch adsorption technique under kinetic and equilibrium conditions. Adsorbent exhibits very high adsorption potential for Hg(II) and more than 99.0% removal was achieved in the pH range 5.5-8.0. Adsorption process was found to follow first-order-reversible kinetics. An increase of ionic strength of the medium caused a decrease in metal removal, indicating the occurrence of outer-sphere surface complex mechanism. The equilibrium data were fitted well by the Freundlich isotherm model (R(2)=0.99; chi(2)=1.81). The removal efficiency was tested using chlor-alkali industry wastewater. Adsorption isotherm experiments were also conducted for comparison using a commercial carboxylate-functionalized ion exchanger, Ceralite IRC-50. Regeneration experiments were tried for four cycles and results indicate a capacity loss of <9.0%. PMID:18313209

  11. Mercury's South Polar Region

    NASA Video Gallery

    This animation shows 89 wide-angle camera (WAC) images of Mercury’s south polar region acquired by the Mercury Dual Imaging System (MDIS) over one complete Mercury solar day (176 Earth days). Thi...

  12. MERCURY IN TREE RINGS

    EPA Science Inventory

    Contamination caused by release of mercury into the environment is a growing concern. This release occurs due to a variety of anthropogenic activities and natural sources. After release, mercury undergoes complicated chemical transformations. The inorganic forms of mercury releas...

  13. Assessing sorbent injection mercury control effectiveness in flue gas streams

    USGS Publications Warehouse

    Carey, T.R.; Richardson, C.F.; Chang, R.; Meserole, F.B.; Rostam-Abadi, M.; Chen, S.

    2000-01-01

    One promising approach for removing mercury from coal-fired, utility flue gas involves the direct injection of mercury sorbents. Although this method has been effective at removing mercury in municipal waste incinerators, tests conducted to date on utility coal-fired boilers show that mercury removal is much more difficult in utility flue gas. EPRI is conducting research to investigate mercury removal using sorbents in this application. Bench-scale, pilot-scale, and field tests have been conducted to determine the ability of different sorbents to remove mercury in simulated and actual flue gas streams. This paper focuses on recent bench-scale and field test results evaluating the adsorption characteristics of activated carbon and fly ash and the use of these results to develop a predictive mercury removal model. Field tests with activated carbon show that adsorption characteristics measured in the lab agree reasonably well with characteristics measured in the field. However, more laboratory and field data will be needed to identify other gas phase components which may impact performance. This will allow laboratory tests to better simulate field conditions and provide improved estimates of sorbent performance for specific sites. In addition to activated carbon results, bench-scale and modeling results using fly ash are presented which suggest that certain fly ashes are capable of adsorbing mercury.

  14. Mercury Continuous Emmission Monitor Calibration

    SciTech Connect

    John Schabron; Eric Kalberer; Ryan Boysen; William Schuster; Joseph Rovani

    2009-03-12

    /mass spectrometry (ID/ICP/MS) performed by NIST in Gaithersburg, MD. The outputs of mercury calibrators are compared to one another using a nesting procedure which allows direct comparison of one calibrator with another at specific concentrations and eliminates analyzer variability effects. The qualification portion of the EPA interim traceability protocol requires the vendors to define calibrator performance as affected by variables such as pressure, temperature, line voltage, and shipping. In 2007 WRI developed and conducted a series of simplified qualification experiments to determine actual calibrator performance related to the variables defined in the qualification portion of the interim protocol.

  15. America's top fifty power plant mercury pollutants

    SciTech Connect

    2008-11-15

    The fifty most-polluting coal-burning power plants in the United States emitted twenty tons of mercury into the air in 2007. Of the ten highest-emitting plants, all but one reported an increase as compared to 2006. Coal-fired power plants are the single largest source of mercury air pollution in the U.S., accounting for roughly 40 per cent of all mercury emissions. This report rates the power plants both in terms of sheer mercury pollution and mercury pollution adjusted per kilowatt hour. It also outlines the ways in which mercury removal is achievable with existing technology. Activated carbon injection, which is commercially available and has been tested, can achieve mercury reductions of 90 per cent (and better when coupled with a fabric filter for particulate control) on both bituminous and sub-bituminous coals. In addition, mercury can be significantly reduced as a 'co-benefit' of controls for other pollutants, such as fabric filters, flue gas desulphurization, and selective catalytic reduction. 3 tabs.

  16. Mercury uptake and accumulation by four species of aquatic plants.

    PubMed

    Skinner, Kathleen; Wright, Nicole; Porter-Goff, Emily

    2007-01-01

    The effectiveness of four aquatic plants including water hyacinth (Eichornia crassipes), water lettuce (Pistia stratiotes), zebra rush (Scirpus tabernaemontani) and taro (Colocasia esculenta) were evaluated for their capabilities in removing mercury from water. The plants were exposed to concentrations of 0 mg/L, 0.5 mg/L or 2 mg/L of mercury for 30 days. Assays were conducted using both Microtox (water) and cold vapor Atomic Absorption Spectroscopy (AAS) (roots and water). The Microtox results indicated that the mercury induced acute toxicity had been removed from the water. AAS confirmed an increase of mercury within the plant root tissue and a corresponding decrease of mercury in the water. All species of plants appeared to reduce mercury concentrations in the water via root uptake and accumulation. Water lettuce and water hyacinth appeared to be the most effective, followed by taro and zebra rush, respectively. PMID:16781033

  17. Mercury's Magnetosphere

    NASA Technical Reports Server (NTRS)

    Slavin, J. A.

    1999-01-01

    Among the major discoveries made by the Mariner 10 mission to the inner planets was the existence of an intrinsic magnetic field at Mercury with a dipole moment of approx. 300 nT R(sup 3, sub M). This magnetic field is sufficient to stand off the solar wind at an altitude of about 1 R(sub M) (i.e. approx. 2439 km). Hence, Mercury possesses a 'magnetosphere' from which the so]ar wind plasma is largely excluded and within which the motion of charged particles is controlled by the planetary magnetic field. Despite its small size relative to the magnetospheres of the other planets, a Mercury orbiter mission is a high priority for the space physics community. The primary reason for this great interest is that Mercury unlike all the other planets visited thus far, lacks a significant atmosphere; only a vestigial exosphere is present. This results in a unique situation where the magnetosphere interacts directly with the outer layer of the planetary crust (i.e. the regolith). At all of the other planets the topmost regions of their atmospheres become ionized by solar radiation to form ionospheres. These planetary ionospheres then couple to electrodynamically to their magnetospheres or, in the case of the weakly magnetized Venus and Mars, directly to the solar wind. This magnetosphere-ionosphere coupling is mediated largely through field-aligned currents (FACs) flowing along the magnetic field lines linking the magnetosphere and the high-latitude ionosphere. Mercury is unique in that it is expected that FACS will be very short lived due to the low electrical conductivity of the regolith. Furthermore, at the earth it has been shown that the outflow of neutral atmospheric species to great altitudes is an important source of magnetospheric plasma (following ionization) whose composition may influence subsequent magnetotail dynamics. However, the dominant source of plasma for most of the terrestrial magnetosphere is the 'leakage'of solar wind across the magnetopause and more

  18. Experimental evaluation of sorbents for the capture of mercury in flue gases

    SciTech Connect

    Livengood, C.D.; Huang, H.S.; Wu, J.M.

    1994-06-01

    The results and conclusions to date from the Argonne research program on air toxics (mercury) control can be summarized as follows: (1) Mercury emissions from coal-fired combustors are generally in the range of 10--70 {mu}g/m{sup 3} and are highly variable. (2) Existing FGC technologies are only partially effective in controlling mercury emissions. (3) Lime hydrates, either regular or high-surface-area, are not effective in removing mercury. (4) Mercury removals are enhanced by the addition of activated carbon. (5) Mercury removals with activated carbon decrease with increasing temperature, larger particle size, and decreasing mercury concentration in the gas. (6) Chemical pretreatment (with sulfur or CaCl{sub 2}) can greatly increase the removal capacity of activated carbon.

  19. Development of dry control technology for emissions of mercury in flue gas

    SciTech Connect

    Huang, Hann S.; Wu, Jiann M.; Livengood, C.D.

    1995-06-01

    In flue gases from coal-combustion systems, mercury in either the elemental state or its chloride form (HgCl{sub 2}) can be predominant among all the possible mercury species present; this predominance largely depends on the chlorine-to-mercury ratio in the coal feeds. Conventional flue-gas cleanup technologies are moderately effective in controlling HgCl{sub 2} but are very poor at controlling elemental mercury. Experiments were conducted on the removal of elemental mercury vapor by means of a number of different types of sorbents, using a fixed-bed adsorption system. Of the four commercial activated carbons evaluated, the sulfur-treated carbon sample gives the best removal performance, with good mercury-sorption capacities. Promising removal results also have been obtained with low-cost minerals after chemical treatments. These inorganic sorbents could potentially be developed into a cost-effective alternative to activated carbons for mercury removal.

  20. A Safe Protocol for Amalgam Removal

    PubMed Central

    Colson, Dana G.

    2012-01-01

    Today's environment has different impacts on our body than previous generations. Heavy metals are a growing concern in medicine. Doctors and individuals request the removal of their amalgam (silver mercury) restorations due to the high mercury content. A safe protocol to replace the silver mercury filling will ensure that there is minimal if any absorption of materials while being removed. Strong alternative white composite and lab-processed materials are available today to create a healthy and functioning mouth. Preparation of the patient prior to the procedure and after treatment is vital to establish the excretion of the mercury from the body. PMID:22315627

  1. Thief carbon catalyst for oxidation of mercury in effluent stream

    DOEpatents

    Granite, Evan J.; Pennline, Henry W.

    2011-12-06

    A catalyst for the oxidation of heavy metal contaminants, especially mercury (Hg), in an effluent stream is presented. The catalyst facilitates removal of mercury through the oxidation of elemental Hg into mercury (II) moieties. The active component of the catalyst is partially combusted coal, or "Thief" carbon, which can be pre-treated with a halogen. An untreated Thief carbon catalyst can be self-promoting in the presence of an effluent gas streams entrained with a halogen.

  2. MERCURY RESEARCH STRATEGY.

    EPA Science Inventory

    The USEPA's ORD is pleased to announce the availability of its Mercury Research Strategy. This strategy guides ORD's mercury research program and covers the FY2001-2005 time frame. ORD will use it to prepare a multi-year mercury research implementation plan in 2001. The Mercury R...

  3. Oxidation of Mercury in Products of Coal Combustion

    SciTech Connect

    Peter Walsh; Giang Tong; Neeles Bhopatkar; Thomas Gale; George Blankenship; Conrad Ingram; Selasi Blavo Tesfamariam Mehreteab; Victor Banjoko; Yohannes Ghirmazion; Heng Ban; April Sibley

    2009-09-14

    Laboratory measurements of mercury oxidation during selective catalytic reduction (SCR) of nitric oxide, simulation of pilot-scale measurements of mercury oxidation and adsorption by unburned carbon and fly ash, and synthesis of new materials for simultaneous oxidation and adsorption of mercury, were performed in support of the development of technology for control of mercury emissions from coal-fired boilers and furnaces. Conversion of gas-phase mercury from the elemental state to water-soluble oxidized form (HgCl{sub 2}) enables removal of mercury during wet flue gas desulfurization. The increase in mercury oxidation in a monolithic V{sub 2}O{sub 5}-WO{sub 3}/TiO{sub 2} SCR catalyst with increasing HCl at low levels of HCl (< 10 ppmv) and decrease in mercury oxidation with increasing NH{sub 3}/NO ratio during SCR were consistent with results of previous work by others. The most significant finding of the present work was the inhibition of mercury oxidation in the presence of CO during SCR of NO at low levels of HCl. In the presence of 2 ppmv HCl, expected in combustion products from some Powder River Basin coals, an increase in CO from 0 to 50 ppmv reduced the extent of mercury oxidation from 24 {+-} 3 to 1 {+-} 4%. Further increase in CO to 100 ppmv completely suppressed mercury oxidation. In the presence of 11-12 ppmv HCl, increasing CO from 0 to {approx}120 ppmv reduced mercury oxidation from {approx}70% to 50%. Conversion of SO{sub 2} to sulfate also decreased with increasing NH{sub 3}/NO ratio, but the effects of HCl and CO in flue gas on SO{sub 2} oxidation were unclear. Oxidation and adsorption of mercury by unburned carbon and fly ash enables mercury removal in a particulate control device. A chemical kinetic mechanism consisting of nine homogeneous and heterogeneous reactions for mercury oxidation and removal was developed to interpret pilot-scale measurements of mercury oxidation and adsorption by unburned carbon and fly ash in experiments at pilot

  4. Anthropogenic mercury emissions in China

    NASA Astrophysics Data System (ADS)

    Streets, David G.; Hao, Jiming; Wu, Ye; Jiang, Jingkun; Chan, Melissa; Tian, Hezhong; Feng, Xinbin

    An inventory of mercury emissions from anthropogenic activities in China is compiled for the year 1999 from official statistical data. We estimate that China's emissions were 536 (±236) t of total mercury. This value includes open biomass burning, but does not include natural sources or re-emission of previously deposited mercury. Approximately 45% of the Hg comes from non-ferrous metals smelting, 38% from coal combustion, and 17% from miscellaneous activities, of which battery and fluorescent lamp production and cement production are the largest. Emissions are heaviest in Liaoning and Guangdong Provinces, where extensive smelting occurs, and in Guizhou Province, where there is much small-scale combustion of high-Hg coal without emission control devices. Emissions are gridded at 30×30 min spatial resolution. We estimate that 56% of the Hg in China is released as Hg 0, 32% as Hg 2+, and 12% as Hg p. Particulate mercury emissions are high in China due to heavy burning of coal in residential and small industrial settings without PM controls. Emissions of Hg 2+ from coal-fired power plants are high due to the absence of flue-gas desulfurization units, which tend to dissolve the soluble divalent mercury. Metals smelting operations favor the production of elemental mercury. Much of the Hg is released from small-scale activities in rather remote areas, and therefore the activity levels are quite uncertain. Also, emissions test data for Chinese sources are lacking, causing uncertainties in Hg emission factors and removal efficiencies. Overall, we calculate an uncertainty level of ±44% (95% confidence interval) in the estimate of total emissions. We recommend field testing of coal combustors and smelters in China to improve the accuracy of these estimates.

  5. ELEMENTAL MERCURY ADSORPTION BY ACTIVATED CARBON TREATED WITH SULFURIC ACID

    EPA Science Inventory

    The paper gives results of a study of the adsorption of elemental mercury at 125 C by a sulfuric-acid (H2S04, 50% w/w/ solution)-treated carbon for the removal of mercury from flue gas. The pore structure of the sample was characterized by nitrogen (N2) at -196 C and the t-plot m...

  6. Demonstration of An Integrated Approach to Mercury Control at Lee Station

    SciTech Connect

    Vitali Lissianski; Pete Maly

    2007-12-31

    General Electric (GE) has developed an approach whereby native mercury reduction on fly ash can be improved by optimizing the combustion system. This approach eliminates carbon-rich areas in the combustion zone, making the combustion process more uniform, and allows increasing carbon content in fly ash without significant increase in CO emissions. Since boiler excess O{sub 2} can be also reduced as a result of optimized combustion, this process reduces NO{sub x} emissions. Because combustion optimization improves native mercury reduction on fly ash, it can reduce requirements for activated carbon injection (ACI) when integrated with sorbent injection for more efficient mercury control. The approach can be tailored to specific unit configurations and coal types for optimal performance. This report describes results of a U.S. DOE sponsored project designed to evaluate the effect of combustion conditions on 'native' mercury capture on fly ash and integrate combustion optimization for improved mercury and NO{sub x} reduction with ACI. The technology evaluation took place in Lee Station Unit 3 located in Goldsboro, NC and operated by Progress Energy. Unit 3 burns a low-sulfur Eastern bituminous coal and is a 250 MW opposed-wall fired unit equipped with an ESP with a specific collection area of 249 ft{sup 2}/kacfm. Unit 3 is equipped with SO{sub 3} injection for ESP conditioning. The technical goal of the project was to evaluate the technology's ability to achieve 70% mercury reduction below the baseline emission value of 2.9 lb/TBtu, which was equivalent to 80% mercury reduction relative to the mercury concentration in the coal. The strategy to achieve the 70% incremental improvement in mercury removal in Unit 3 was (1) to enhance 'naturally' occurring fly ash mercury capture by optimizing the combustion process and using duct humidification to reduce flue gas temperatures at the ESP inlet, and (2) to use ACI in front of the ESP to further reduce mercury emissions. The

  7. Slanted baffle mist eliminator

    DOEpatents

    Vance, Richard F.

    1995-01-01

    An apparatus for the elimination of mist from off-gas during vitrification f nuclear waste, where baffles are installed on a slant toward the flow of the off-gasses eliminating the need to expand the cross-sectional area of the duct size.

  8. Slanted baffle mist eliminator

    DOEpatents

    Vance, Richard F.

    1995-11-07

    An apparatus for the elimination of mist from off-gas during vitrification f nuclear waste, where baffles are installed on a slant toward the flow of the off-gasses eliminating the need to expand the cross-sectional area of the duct size.

  9. Formation of Mercury Sulfide from Hg(II)-Thiolate Complexes in Natural Organic Matter.

    PubMed

    Manceau, Alain; Lemouchi, Cyprien; Enescu, Mironel; Gaillot, Anne-Claire; Lanson, Martine; Magnin, Valérie; Glatzel, Pieter; Poulin, Brett A; Ryan, Joseph N; Aiken, George R; Gautier-Luneau, Isabelle; Nagy, Kathryn L

    2015-08-18

    Methylmercury is the environmental form of neurotoxic mercury that is biomagnified in the food chain. Methylation rates are reduced when the metal is sequestered in crystalline mercury sulfides or bound to thiol groups in macromolecular natural organic matter. Mercury sulfide minerals are known to nucleate in anoxic zones, by reaction of the thiol-bound mercury with biogenic sulfide, but not in oxic environments. We present experimental evidence that mercury sulfide forms from thiol-bound mercury alone in aqueous dark systems in contact with air. The maximum amount of nanoparticulate mercury sulfide relative to thiol-bound mercury obtained by reacting dissolved mercury and soil organic matter matches that detected in the organic horizon of a contaminated soil situated downstream from Oak Ridge, TN, in the United States. The nearly identical ratios of the two forms of mercury in field and experimental systems suggest a common reaction mechanism for nucleating the mineral. We identified a chemical reaction mechanism that is thermodynamically favorable in which thiol-bound mercury polymerizes to mercury-sulfur clusters. The clusters form by elimination of sulfur from the thiol complexes via breaking of mercury-sulfur bonds as in an alkylation reaction. Addition of sulfide is not required. This nucleation mechanism provides one explanation for how mercury may be immobilized, and eventually sequestered, in oxygenated surface environments. PMID:26168020

  10. Mercury Quick Facts: Health Effects of Mercury Exposure

    MedlinePlus

    Mercury Quick Facts Health Effects of Mercury Exposure What is Elemental Mercury? Elemental (metallic) mercury is the shiny, silver-gray metal found in thermometers, barometers, and thermostats and other ...

  11. Investigations of photochemical transformations of aqueous mercury: implications for water effluent treatment technologies.

    PubMed

    Byrne, Heather E; Borello, Amy; Bonzongo, Jean-Claude; Mazyck, David W

    2009-09-01

    Photochemical transformations of mercury were studied to determine its potential as a treatment mechanism to reduce mercury laden waters to trace concentrations. In this study, aqueous solutions of mercury nitrate in deionized water were exposed to UV irradiation and a gas purge. The impacts of purge gas (including rate and bubble size), UV irradiation wavelength, initial mercury concentration and time on mercury removal have been studied. Nitrogen purge with 254 nm UV irradiation resulted in the greatest net production of elemental mercury for all initial concentrations. These conditions followed pseudo first order kinetics and achieved the highest rate constant of 0.18s(-1). As oxygen was introduced into the solution, the quantity of elemental mercury volatilized decreased but still resulted in significant mercury losses through volatilization up to 90% in 60 min. Overriding, the loss of elemental mercury from the solution is dependent upon the gas purge rate and bubble size. PMID:19595425

  12. Combined tween 20-stabilized gold nanoparticles and reduced graphite oxide-Fe3O4 nanoparticle composites for rapid and efficient removal of mercury species from a complex matrix.

    PubMed

    Shih, Ya-Chen; Ke, Chen-Yi; Yu, Cheng-Ju; Lu, Chi-Yu; Tseng, Wei-Lung

    2014-10-22

    This study describes a simple method for removing mercuric ions (Hg(2+)) from a high-salt matrix based on the use of Tween-20-stabilized gold nanoparticles (Tween 20-Au NPs) as Hg(2+) adsorbents and composites of reduced graphite oxide and Fe3O4 NPs as NP collectors. Citrate ions adsorbed on the surface of the Tween 20-Au NPs reduced Hg(2+) to Hg(0), resulting in the deposition of Hg(0) on the surface of the NPs. To circumvent time-consuming centrifugation and transfer steps, the Hg(0)-containing gold NPs were collected using reduced graphite oxide-Fe3O4 NP composites. Compared with the reported NP-based methods for removing Hg(2+), Tween 20-Au NPs offered the rapid (within 30 min), efficient (>99% elimination efficiency), durable (>10 cycles), and selective removal of Hg(2+), CH3Hg(+), and C2H5Hg(+) in a high-salt matrix without the interference of other metal ions. This was attributed to the fact that the dispersed Tween 20-Au NPs exhibited large surface-area-to-volume ratio to bind Hg(2+) through Hg(2+)-Au(+) metallophilic interactions in a high-salt matrix. The formation of graphite oxide sheets and reduced graphite oxide-Fe3O4 NP composites was demonstrated using X-ray diffraction, X-ray photoelectron spectroscopy, Raman spectroscopy, Fourier transform infrared spectrometry, and transmission electron microscopy. The mechanism of interaction between Tween 20-Au NPs and Hg(2+) was studied using visible spectroscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. PMID:25238563

  13. Mercury Bioaccumulation Potential from Wastewater Treatment Plants in Receiving Waters

    NASA Astrophysics Data System (ADS)

    Dean, J. D.; Mason, R. P.

    2008-12-01

    In early 2007, the Water Environment Research Foundation (WERF) mercury bioavailability project was initiated in response to the establishment of mercury Total Maximum Daily Load (TMDL) criteria around the country. While many TMDLs recognize that point sources typically constitute a small fraction of the mercury load to a water body, the question was raised concerning the relative bioavailablity of mercury coming from various sources. For instance, is the mercury discharged from a wastewater treatment plant more or less bioavailable than mercury contributed from other sources? This talk will focus on the results of a study investigating approaches to the estimation of bioavailability and potential bioaccumulation of mercury from wastewater treatment plants and other sources in receiving waters. From the outset, a working definition of bioavailability was developed which included not only methylmercury, the form that readily bioaccumulates in aquatic food chains, but also bioavailable inorganic mercury species that could be converted to methylmercury within a scientifically reasonable time frame. Factors that enhance or mitigate the transformation of inorganic mercury to methylmercury and its subsequent bioaccumulation were identified. Profiles were developed for various sources of mercury in watersheds, including wastewater treatment plants, with regard to methylmercury and inorganic bioavailable mercury, and the key factors that enhance or mitigate mercury bioavailability. Technologies that remove mercury from wastewater were reviewed and evaluated for their effect on bioavailability. A screening procedure was developed for making preliminary estimates of bioavailable mercury concentrations and fluxes in wastewater effluents and in fresh, estuarine and marine receiving waters. The procedure was validated using several diverse river and reservoir data sets. A "Bioavailability Tool" was developed which allows a user to estimate the bioavailability of an effluent and

  14. In situ remediation technologies for mercury-contaminated soil

    DOE PAGESBeta

    He, Feng; Gao, Jie; Pierce, Eric; Strong, P. J.; Wang, Hailong; Liang, Liyuan

    2015-04-09

    A pollutant that poses significant risks to humans and the environment is mercury from anthropogenic activities. In soils, mercury remediation can be technically challenging and costly, depending on the subsurface mercury distribution, the types of mercury species, and the regulatory requirements. Our paper introduces the chemistry of mercury and its implications for in situ mercury remediation, which is followed by a detailed discussion of several in situ Hg remediation technologies in terms of applicability, cost, advantages, and disadvantages. The effect of Hg speciation on remediation performance, as well as Hg transformation during different remediation processes, was detailed. Thermal desorption, electrokinetic,more » and soil flushing/washing treatments are removal technologies that mobilize and capture insoluble Hg species, while containment, solidification/stabilization, and vitrification immobilize Hg by converting it to less soluble forms. We also discussed two emerging technologies, phytoremediation and nanotechnology, in this review.« less

  15. In situ remediation technologies for mercury-contaminated soil.

    PubMed

    He, Feng; Gao, Jie; Pierce, Eric; Strong, P J; Wang, Hailong; Liang, Liyuan

    2015-06-01

    Mercury from anthropogenic activities is a pollutant that poses significant risks to humans and the environment. In soils, mercury remediation can be technically challenging and costly, depending on the subsurface mercury distribution, the types of mercury species, and the regulatory requirements. This paper introduces the chemistry of mercury and its implications for in situ mercury remediation, which is followed by a detailed discussion of several in situ Hg remediation technologies in terms of applicability, cost, advantages, and disadvantages. The effect of Hg speciation on remediation performance, as well as Hg transformation during different remediation processes, was detailed. Thermal desorption, electrokinetic, and soil flushing/washing treatments are removal technologies that mobilize and capture insoluble Hg species, while containment, solidification/stabilization, and vitrification immobilize Hg by converting it to less soluble forms. Two emerging technologies, phytoremediation and nanotechnology, are also discussed in this review. PMID:25850737

  16. In situ remediation technologies for mercury-contaminated soil

    SciTech Connect

    He, Feng; Gao, Jie; Pierce, Eric; Strong, P. J.; Wang, Hailong; Liang, Liyuan

    2015-04-09

    A pollutant that poses significant risks to humans and the environment is mercury from anthropogenic activities. In soils, mercury remediation can be technically challenging and costly, depending on the subsurface mercury distribution, the types of mercury species, and the regulatory requirements. Our paper introduces the chemistry of mercury and its implications for in situ mercury remediation, which is followed by a detailed discussion of several in situ Hg remediation technologies in terms of applicability, cost, advantages, and disadvantages. The effect of Hg speciation on remediation performance, as well as Hg transformation during different remediation processes, was detailed. Thermal desorption, electrokinetic, and soil flushing/washing treatments are removal technologies that mobilize and capture insoluble Hg species, while containment, solidification/stabilization, and vitrification immobilize Hg by converting it to less soluble forms. We also discussed two emerging technologies, phytoremediation and nanotechnology, in this review.

  17. MERCURY CONTROL WITH CALCIUM-BASED SORBENTS AND OXIDIZING AGENTS

    SciTech Connect

    Thomas K. Gale

    2002-06-01

    The initial tasks of this DOE funded project to investigate mercury removal by calcium-based sorbents have been completed, and initial testing results have been obtained. Mercury monitoring capabilities have been obtained and validated. An approximately 1MW (3.4 Mbtu/hr) Combustion Research Facility at Southern Research Institute was used to perform pilot-scale investigations of mercury sorbents, under conditions representative of full-scale boilers. The initial results of ARCADIS G&M proprietary sorbents, showed ineffective removal of either elemental or oxidized mercury. Benchscale tests are currently underway to ascertain the importance of differences between benchscale and pilot-scale experiments. An investigation of mercury-capture temperature dependence using common sorbents has also begun. Ordinary hydrated lime removed 80 to 90% of the mercury from the flue gas, regardless of the temperature of injection. High temperature injection of hydrated lime simultaneously captured SO{sub 2} at high temperatures and Hg at low temperatures, without any deleterious effects on mercury speciation. Future work will explore alternative methods of oxidizing elemental mercury.

  18. Implications of mercury interactions with band-gap semiconductor oxides

    SciTech Connect

    Granite, E.J.; King, W.P.; Stanko, D.C.; Pennline, H.W.

    2008-09-01

    Titanium dioxide is a well-known photooxidation catalyst. It will oxidize mercury in the presence of ultraviolet light from the sun and oxygen and/or moisture to form mercuric oxide. Several companies manufacture self-cleaning windows. These windows have a transparent coating of titanium dioxide. The titanium dioxide is capable of destroying organic contaminants in air in the presence of ultraviolet light from the sun, thereby keeping the windows clean. The commercially available self-cleaning windows were used to sequester mercury from oxygen–nitrogen mixtures. Samples of the self-cleaning glass were placed into specially designed photo-reactors in order to study the removal of elemental mercury from oxygen–nitrogen mixtures resembling air. The possibility of removing mercury from ambient air with a self-cleaning glass apparatus is examined. The intensity of 365-nm ultraviolet light was similar to the natural intensity from sunlight in the Pittsburgh region. Passive removal of mercury from the air may represent an option in lieu of, or in addition to, point source clean-up at combustion facilities. There are several common band-gap semiconductor oxide photocatalysts. Sunlight (both the ultraviolet and visible light components) and band-gap semiconductor particles may have a small impact on the global cycle of mercury in the environment. The potential environmental consequences of mercury interactions with band-gap semiconductor oxides are discussed. Heterogeneous photooxidation might impact the global transport of elemental mercury emanating from flue gases.

  19. Evaluation of Sorbent Injection for Mercury Control

    SciTech Connect

    Sharon Sjostrom

    2005-12-30

    The power industry in the U.S. is faced with meeting new regulations to reduce the emissions of mercury compounds from coal-fired plants. These regulations are directed at the existing fleet of nearly 1,100 boilers. These plants are relatively old with an average age of over 40 years. Although most of these units are capable of operating for many additional years, there is a desire to minimize large capital expenditures because of the reduced (and unknown) remaining life of the plant to amortize the project. Injecting a sorbent such as powdered activated carbon into the flue gas represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. This is the final site report for tests conducted at Laramie River Station Unit 3, one of five sites evaluated in this DOE/NETL program. The overall objective of the test program is to evaluate the capabilities of activated carbon injection at five plants: Sunflower Electric's Holcomb Station Unit 1, AmerenUE's Meramec Station Unit 2, Missouri Basin Power Project's Laramie River Station Unit 3, Detroit Edison's Monroe Power Plant Unit 4, and AEP's Conesville Station Unit 6. These plants have configurations that together represent 78% of the existing coal-fired generation plants. The goals for the program established by DOE/NETL are to reduce the uncontrolled mercury emissions by 50 to 70% at a cost 25 to 50% lower than the benchmark established by DOE of $60,000/lb mercury removed. The goals of the program were exceeded at Laramie River Station by achieving over 90% mercury removal at a sorbent cost of $3,980/lb ($660/oz) mercury removed for a coal mercury content of 7.9 lb/TBtu.

  20. Global Trends in Mercury Management

    PubMed Central

    Choi, Kyunghee

    2012-01-01

    The United Nations Environmental Program Governing Council has regulated mercury as a global pollutant since 2001 and has been preparing the mercury convention, which will have a strongly binding force through Global Mercury Assessment, Global Mercury Partnership Activities, and establishment of the Open-Ended Working Group on Mercury. The European Union maintains an inclusive strategy on risks and contamination of mercury, and has executed the Mercury Export Ban Act since December in 2010. The US Environmental Protection Agency established the Mercury Action Plan (1998) and the Mercury Roadmap (2006) and has proposed systematic mercury management methods to reduce the health risks posed by mercury exposure. Japan, which experienced Minamata disease, aims vigorously at perfection in mercury management in several ways. In Korea, the Ministry of Environment established the Comprehensive Plan and Countermeasures for Mercury Management to prepare for the mercury convention and to reduce risks of mercury to protect public health. PMID:23230466

  1. Dynamics of mercury in blood and feathers of great skuas

    SciTech Connect

    Bearhop, S.; Ruxton, G.D.; Furness, R.W.

    2000-06-01

    Mercury dynamics in the blood and feathers of captive great skuas, Catharacta skua, were monitored over 56 weeks. Prior to the onset of molt, mercury intake was solely from their maintenance ration of sprats, Sprattus sprattus. For the first half of molt, in addition to mercury intake from sprats, birds were fed different doses of methylmercuric chloride weekly for 20 weeks. During the second half of molt, dosing was stopped and mercury intake was solely from sprats. Blood was sampled throughout the study and feather growth was monitored. Prior to the onset of molt, mercury concentrations increased over the first 51 to 71 d and appeared to level off after this period. Repeated dosing models based on mammalian pharmacokinetics were, in general, too simplistic to be applicable to the birds in the study. During molt, the elimination of mercury from the blood is probably best described by a three-compartment model. Mercury concentrations in feathers were significantly correlated with those in blood at the time of their growth, suggesting that blood and feathers reflect mercury intake over the same time period. Individuals varied in their ability to excrete ingested mercury into the feathers.

  2. New Jersey mercury regulations

    SciTech Connect

    Elias, D.F.; Corbin, W.E.

    1996-12-31

    Mercury, or quicksilver, and its major ore cinnabar (HgS) have been known for thousands of years. Health effects from mercury such as dementia were known as early as the late 19th century ({open_quotes}mad as a hatter{close_quotes}). In the 1960`s and 1970`s, reported levels of mercury in tuna reawakened public awareness of mercury pollution. In the 1970`s, major epidemics of acute mercury poisoning were reported in Japan and Iraq. These incidents highlighted the extreme health risks, such as kidney damage, birth defects, and death, associated with severe mercury poisoning. Fetuses and young children are particularly vulnerable since mercury poisoning can damage growing neural tissues. Recently, the perception of mercury as a dangerous pollutant has been on the rise. Advisories warning the public to avoid or reduce the consumption of freshwater fish caught in specific waterbodies due to mercury contamination have been issued in numerous states. The discovery of mercury in {open_quotes}pristine{close_quotes} lakes in the United States, Canada, and Scandinavia, remote from industry and any known mercury sources, has focused attention on atmospheric emissions of mercury as potential significant sources of mercury.

  3. Mercury control challenge for industrial boiler MACT affected facilities

    SciTech Connect

    2009-09-15

    An industrial coal-fired boiler facility conducted a test program to evaluate the effectiveness of sorbent injection on mercury removal ahead of a fabric filter with an inlet flue gas temperature of 375{sup o}F. The results of the sorbent injection testing are essentially inconclusive relative to providing the facility with enough data upon which to base the design and implementation of permanent sorbent injection system(s). The mercury removal performance of the sorbents was significantly less than expected. The data suggests that 50 percent mercury removal across a baghouse with flue gas temperatures at or above 375{sup o}F and containing moderate levels of SO{sub 3} may be very difficult to achieve with activated carbon sorbent injection alone. The challenge many coal-fired industrial facilities may face is the implementation of additional measures beyond sorbent injection to achieve high levels of mercury removal that will likely be required by the upcoming new Industrial Boiler MACT rule. To counter the negative effects of high flue gas temperature on mercury removal with sorbents, it may be necessary to retrofit additional boiler heat transfer surface or spray cooling of the flue gas upstream of the baghouse. Furthermore, to counter the negative effect of moderate or high SO{sub 3} levels in the flue gas on mercury removal, it may be necessary to also inject sorbents, such as trona or hydrated lime, to reduce the SO{sub 3} concentrations in the flue gas. 2 refs., 1 tab.

  4. Comparative effects of chelating agents on distribution, excretion, and renal toxicity of inorganic mercury in rats

    SciTech Connect

    Kojima, S.; Shimada, H.; Kiyozumi, M. )

    1989-06-01

    The effects of three chelating agents, sodium N-benzyl-D-glucamine dithiocarbamate(NBG-DTC), 2,3-dimercaptopropanol(BAL), and D-penicillamine(D-PEN), on the distribution, excretion, and renal toxicity of inorganic mercury were compared in rats exposed to HgCl2. Rats were injected i.p. with 203HgCl2 (300 micrograms of Hg and 2 microCi of 203Hg/kg) and 30 min or 24 h later they were injected with a chelating agent (a quarter of an LD50). The injection of the chelating agents significantly enhanced the biliary and urinary excretions of mercury. BAL was the most effective for removal of mercury from the body at 30 min after mercury treatment. The extent of enhancing effect of the chelating agents for removal of mercury at 24 h after mercury was in the order NBG-DTC = BAL greater than D-PEN. The injection of BAL at 24 h after mercury treatment caused the redistribution of mercury to the heart and lung. NBG-DTC did not result in the redistribution of mercury to the heart, lung, and brain. Urinary excretion of protein and AST significantly increased 24-48 h after mercury treatment and decreased to the control values 72 h after mercury. The injection of the chelating agents at 30 min after mercury treatment significantly decreased the urinary excretion of protein and AST. In rats pretreated with mercury 24 h earlier, the chelating agents significantly decreased the urinary protein at 48 h after mercury treatment, but did not decrease the urinary AST. The results of this study indicate that the chelating agents are effective in removing mercury from the body, resulting in the protective effect against the mercury-induced renal damage.

  5. Development of mercury control technology for coal-fired systems

    SciTech Connect

    Livengood, D.C.; Huang, H.S.; Mendelsohn, M.H.; Wu, Jiann M.

    1995-08-01

    The emission of hazardous air pollutants (air toxics) from various industrial processes has emerged as a major environmental issue that was singled out for particular attention in the Clean Air Act Amendments of 1990. In particular, mercury emissions are the subject of several current EPA studies because of concerns over possible serious effects on human health. Some of those emissions originate in the combustion of coal, which contains trace amounts of mercury, and are likely to be the subject of control requirements in the relatively near future. Data collected by the Department of Energy (DOE) and the Electric Power Research Institute (EPRI) at operating electric-power plants have shown that conventional flue-gas cleanup (FGC) technologies are not very effective in controlling emissions of mercury in general, and are particularly poor at controlling emissions of elemental mercury. This paper gives an overview of research being conducted at Argonne National Laboratory on improving the capture of mercury in flue gas through the use of dry sorbents and/or wet scrubbers. The results and conclusions to date from the Argonne research on dry sorbents can be summarized as follows: lime hydrates, either regular or high-surface-area, are not effective in removing elemental mercury; mercury removals are enhanced by the addition of activated carbon; mercury removals with activated carbon decrease with increasing temperature, larger particle size, and decreasing mercury concentration in the gas; chemical pretreatment (e.g., with sulfur or CaCl{sub 2}) can greatly increase the removal capacity of activated carbon; chemically treated mineral substrates have the potential to be developed into effective and economical mercury sorbents; sorbents treated with different chemicals respond in significantly different ways to changes in flue-gas temperature.

  6. The Plasma Environment at Mercury

    NASA Technical Reports Server (NTRS)

    Raines, James M.; Gershman, Daniel J.; Zurbuchen, Thomas H.; Gloeckler, George; Slavin, James A.; Anderson, Brian J.; Korth, Haje; Krimigis, Stamatios M.; Killen, Rosemary M.; Sarantos, Menalos; Sprague, Anne L.; McNutt, Ralph L., Jr.

    2011-01-01

    Mercury is the least explored terrestrial planet, and the one subjected to the highest flux of solar radiation in the heliosphere. Its highly dynamic, miniature magnetosphere contains ions from the exosphere and solar wind, and at times may allow solar wind ions to directly impact the planet's surface. Together these features create a plasma environment that shares many features with, but is nonetheless very different from, that of Earth. The first in situ measurements of plasma ions in the Mercury space environment were made only recently, by the Fast Imaging Plasma Spectrometer (FIPS) during the MESSENGER spacecraft's three flybys of the planet in 2008-2009 as the probe was en route to insertion into orbit about Mercury earlier this year. Here. we present analysis of flyby and early orbital mission data with novel techniques that address the particular challenges inherent in these measurements. First. spacecraft structures and sensor orientation limit the FIPS field of view and allow only partial sampling of velocity distribution functions. We use a software model of FIPS sampling in velocity space to explore these effects and recover bulk parameters under certain assumptions. Second, the low densities found in the Mercury magnetosphere result in a relatively low signal-to-noise ratio for many ions. To address this issue, we apply a kernel density spread function to guide removal of background counts according to a background-signature probability map. We then assign individual counts to particular ion species with a time-of-flight forward model, taking into account energy losses in the carbon foil and other physical behavior of ions within the instrument. Using these methods, we have derived bulk plasma properties and heavy ion composition and evaluated them in the context of the Mercury magnetosphere.

  7. Interim Results from a Study of the Impacts of Tin (II) Based Mercury Treatment in a Small Stream Ecosystem: Tims Branch, Savannah River Site

    SciTech Connect

    Looney, Brian; BryanJr., Larry; Mathews, Teresa J; Peterson, Mark J; Roy, W Kelly; Jett, Robert T; Smith, John G

    2012-03-01

    A research team is assessing the impacts of an innovative mercury treatment system in Tims Branch, a small southeastern stream. The treatment system, installed in 2007, reduces and removes inorganic mercury from water using tin(II) (stannous) chloride addition followed by air stripping. The system results in discharge of inorganic tin to the ecosystem. This screening study is based on historical information combined with measurements of contaminant concentrations in water, fish, sediment, biofilms and invertebrates. Initial mercury data indicate that first few years of mercury treatment resulted in a significant decrease in mercury concentration in an upper trophic level fish, redfin pickerel, at all sampling locations in the impacted reach. For example, the whole body mercury concentration in redfin pickerel collected from the most impacted pond decreased approximately 72% between 2006 (pre-treatment) and 2010 (post-treatment). Over this same period, mercury concentrations in the fillet of redfin pickerel in this pond were estimated to have decreased from approximately 1.45 {micro}g/g (wet weight basis) to 0.45 {micro}g/g - a decrease from 4.8x to 1.5x the current EPA guideline concentration for mercury in fillet (0.3 {micro}g/g). Thermodynamic modeling, scanning electron microscopy, and other sampling data for tin suggest that particulate tin (IV) oxides are a significant geochemical species entering the ecosystem with elevated levels of tin measured in surficial sediments and biofilms. Detectable increases in tin in sediments and biofilms extended approximately 3km from the discharge location. Tin oxides are recalcitrant solids that are relatively non-toxic and resistant to dissolution. Work continues to develop and validate methods to analyze total tin in the collected biota samples. In general, the interim results of this screening study suggest that the treatment process has performed as predicted and that the concentration of mercury in upper trophic level

  8. Changing patterns in the use, recycling, and material substitution of mercury in the United States

    USGS Publications Warehouse

    Wilburn, David R.

    2013-01-01

    Environmental concerns have led to numerous regulations that have dramatically decreased the reported production and use of mercury in the United States since the 1980s. Government legislation and subsequent industry actions have led to increased collection of mercury-containing materials and the recovery of mercury through recycling. Mercury emissions have been reduced and effective alternatives to mercury products have been developed for many applications. This study updates and quantifies the changes in demand, supply, use, and material flow for mercury in various sectors in the United States that have taken place since 1996. Nearly all primary mercury produced in the United States is derived as a byproduct of processing of gold and silver ore in Nevada. Since 2001, annual production of mercury from gold and silver mining in Nevada has decreased by 22 percent overall because ore from greater depths containing low grade mercury is recovered, and mercury emissions from this source have decreased by 95 percent as a result of increased regulation and improved collection and suppression technology. The distribution of consumption of mercury in the United States has changed as a result of regulation (elimination of large-scale mercury use in the paint and battery sectors), reduction by consumers (decommissioning of mercury-cell chloralkali manufacturing capacity), and technological advances (improvements in dental, lighting, and wiring sectors). Mercury use in the chloralkali sector, the leading end-use sector in the United States in 1996, has declined by 98 percent from 136 metric tons (t) in 1996 to about 0.3 t in 2010 because of increased processing and recycling efficiencies and plant closures or conversion to other technologies. As plants were closed, mercury recovered from the infrastructure of decommissioned plants has been exported, making the United States a net exporter of mercury, even though no mercury has been produced as the primary product from mines in

  9. Geochemical, Genetic, and Community Controls on Mercury

    SciTech Connect

    Wall, Judy D.

    2014-11-10

    The sulfate-reducing bacteria (SRB) are soil bacteria that share two common characteristics, strict anaerobiosis and the ability to respire sulfate. The metabolic activities of these bacteria play significant roles in the global sulfur cycle, anaerobic degradation of biomass, biological metal corrosion in the environment and, recently, degradation of toxic compounds. The accumulation of evidence suggests these bacteria are also key to the production of the neurotoxin methylmercury in environmental settings. We propose to use our experience with the development of genetics in sulfate-reducing bacteria of the genus Desulfovibrio to create mutations that will eliminate the methylation of mercury, thereby identifying the genes essential for this process. This information may allow the environmental monitoring of the mercury methylation potential to learn the location and quantity of the production this toxin. From these data, more accurate predictive models of mercury cycling can be generated.

  10. SELECTIVE CATALYTIC REDUCTION MERCURY FIELD SAMPLING PROJECT

    EPA Science Inventory

    A lack of data still exists as to the effect of selective catalytic reduction (SCR), selective noncatalytic reduction (SNCR), and flue gas conditioning on the speciation and removal of mercury (Hg) at power plants. This project investigates the impact that SCR, SNCR, and flue gas...

  11. Amended Silicated for Mercury Control

    SciTech Connect

    James Butz; Thomas Broderick; Craig Turchi

    2006-12-31

    Amended Silicates{trademark}, a powdered, noncarbon mercury-control sorbent, was tested at Duke Energy's Miami Fort Station, Unit 6 during the first quarter of 2006. Unit 6 is a 175-MW boiler with a cold-side electrostatic precipitator (ESP). The plant burns run-of-the-river eastern bituminous coal with typical ash contents ranging from 8-15% and sulfur contents from 1.6-2.6% on an as-received basis. The performance of the Amended Silicates sorbent was compared with that for powdered activated carbon (PAC). The trial began with a period of baseline monitoring during which no sorbent was injected. Sampling during this and subsequent periods indicated mercury capture by the native fly ash was less than 10%. After the baseline period, Amended Silicates sorbent was injected at several different ratios, followed by a 30-day trial at a fixed injection ratio of 5-6 lb/MMACF. After this period, PAC was injected to provide a comparison. Approximately 40% mercury control was achieved for both the Amended Silicates sorbent and PAC at injection ratios of 5-6 lbs/MMACF. Higher injection ratios did not achieve significantly increased removal. Similar removal efficiencies have been reported for PAC injection trials at other plants with cold-side ESPs, most notably for plants using medium to high sulfur coal. Sorbent injection did not detrimentally impact plant operations and testing confirmed that the use of Amended Silicates sorbent does not degrade fly ash quality (unlike PAC). The cost for mercury control using either PAC or Amended Silicates sorbent was estimated to be equivalent if fly ash sales are not a consideration. However, if the plant did sell fly ash, the effective cost for mercury control could more than double if those sales were no longer possible, due to lost by-product sales and additional cost for waste disposal. Accordingly, the use of Amended Silicates sorbent could reduce the overall cost of mercury control by 50% or more versus PAC for locations where fly

  12. MERCURY(II) ADSORPTION FROM WASTEWATERS USING A THIOL FUNCTIONAL ADSORBENT

    EPA Science Inventory

    The removal of mercury(II) from wastewaters (coal-fired utility plant scrubber solutions) using a thiol functional organoceramic composite (SOL-AD-IV) is investigated. A simulant is employed as a surrogate to demonstrate the removal of mercury from real waste solutions. Equilibri...

  13. Mercury Surveillance Program

    NASA Technical Reports Server (NTRS)

    1993-01-01

    Background on mercury exposure is presented including forms, sources, permissible exposure limits, and physiological effects. The purpose of the Mercury Surveillance Program at LeRC is outlined, and the specifics of the Medical Surveillance Program for Mercury Exposure at LeRC are discussed.

  14. MERCURY IN THE ENVIRONMENT

    EPA Science Inventory

    Mercury is released from a variety of sources and exhibits a complicated chemistry. According to the Mercury Study Report to Congress, mercury fluxes and budgets in water, soil, and other media have increased by a factor of two to five over pre-industrial levels. The primary expo...

  15. Mercury in the environment

    NASA Technical Reports Server (NTRS)

    Fulkerson, W.; Lyon, W. S.; Shults, W. D.; Wallace, R. A.

    1972-01-01

    Problems in assessing mercury concentrations in environmental materials are discussed. Data for situations involving air, water, rocks, soils, sediments, sludges, fossil fuels, plants, animals, foods, and man are drawn together and briefly evaluated. Details are provided regarding the toxicity of mercury along with tentative standards and guidelines for mercury in air, drinking water, and food.

  16. Enhanced Control of Mercury and other HAP by Innovative Modifications to Wet FGD Processes

    SciTech Connect

    Hargrove, O. W.; Carey, T. R.; Richardson, C. F.; Skarupa, R. C.; Meserole, F. B.; Rhudy, R. G.; Brown, Thomas D.

    1997-07-01

    The overall objective of this project was to learn more about controlling emissions of hazardous air pollutants (HAPs) from coal-fired power plants that are equipped with wet flue gas desulfurization (FGD) systems. The project was included by FETC as a Phase I project in its Mega-PRDA program. Phase I of this project focused on three research areas. These areas in order of priority were: (1) Catalytic oxidation of vapor-phase elemental mercury; (2) Enhanced particulate-phase HAPs removal by electrostatic charging of liquid droplets; and (3) Enhanced mercury removal by addition of additives to FGD process liquor. Mercury can exist in two forms in utility flue gas--as elemental mercury and as oxidized mercury (predominant form believed to be HgCl{sub 2}). Previous test results have shown that wet scrubbers effectively remove the oxidized mercury from the gas but are ineffective in removing elemental mercury. Recent improvements in mercury speciation techniques confirm this finding. Catalytic oxidation of vapor-phase elemental mercury is of interest in cases where a wet scrubber exists or is planned for SO{sub 2} control. If a low-cost process could be developed to oxidize all of the elemental mercury in the flue gas, then the maximum achievable mercury removal across the existing or planned wet scrubber would increase. Other approaches for improving control of HAPs included a method for improving particulate removal across the FGD process and the use of additives to increase mercury solubility. This paper discusses results related only to catalytic oxidation of elemental mercury.

  17. Field Demonstration of Enhanced Sorbent Injection for Mercury Control

    SciTech Connect

    Shin Kang; Robert Schrecengost

    2009-01-07

    Alstom Power Inc. has conducted a DOE/NETL-sponsored program (under DOE Cooperative Agreement No. DE-FC26-04NT42306) to demonstrate Mer-Cure{trademark}, one of Alstom's mercury control technologies for coal-fired boilers. Mer-Cure{trademark} utilizes a small amount of Mer-Clean{trademark} sorbent that is injected into the flue gas stream for oxidation and adsorption of gaseous mercury. Mer-Clean{trademark} sorbents are carbon-based and prepared with chemical additives that promote oxidation and capture of mercury. Mer-Cure{trademark} is unique in that the sorbent is injected into an environment where the mercury capture kinetics is accelerated. This full-scale demonstration program was comprised of three seven-week long test campaigns at three host sites including PacifiCorp's 240-MW{sub e} Dave Johnston Unit No.3 burning a Powder River Basin (PRB) coal, Basin Electric's 220-MW{sub e} Leland Olds Unit No.1 burning a North Dakota lignite, and Reliant Energy's 170-MW{sub e} Portland Unit No.1 burning an Eastern bituminous coal. All three boilers are equipped with electrostatic precipitators. The goals for this Round 2 program, established by DOE/NETL under the original solicitation, were to reduce the uncontrolled mercury emissions by 50 to 70% at a cost 25 to 50% lower than the previous target of $60,000/lb mercury removed. The results for all three host sites indicated that Mer-Cure{trademark} technology could achieve mercury removal of 90%. The estimated mercury removal costs were 25-92% lower than the benchmark of $60,000/lb mercury removed. The estimated costs for control, at sorbent cost of $1.25 to $2.00/lb respectively, are as follows: (1) Dave Johnston Unit No.3--$2,650 to $4,328/lb Hg removed (92.8% less than $60k/lb); (2) Leland Olds Unit No.1--$8,680 to $13,860/lb Hg removed (76.7% less than $60k/lb); and (3) Portland Unit No.1--$28,540 to $45,065/lb Hg removed (24.9% less than $60k/lb). In summary, the results from demonstration testing at all three host

  18. Phyto extraction and accumulation of mercury in selected plant species grown in soil contaminated with different mercury compounds

    SciTech Connect

    Su, Y.; Han, F.; Shiyab, S.; Monts, D.L.

    2007-07-01

    The objective of our research is to screen and search for suitable plant species for phyto-remediation of mercury-contaminated soil. Currently our effort is specifically focused on mercury removal from the U.S. Department of Energy's (DOE) Oak Ridge Site, where mercury contamination is a major concern in the Y-12 Watershed area. In order to cost effectively implement those remediation efforts currently planned for FY09, it is necessary now to obtain an improved understanding of biological means of removing mercury and mercury compounds from the Oak Ridge ecosystem. Phyto-remediation is a technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. In particular, phyto-extraction is the uptake of contaminants by plant roots and translocation within the plants to shoots or leaves. Contaminants are generally removed by harvesting the plants. We have investigated phyto-extraction of mercury from contaminated soil by using some of the known metal accumulating wild plants since no natural plant species with mercury hyper-accumulating properties has yet been identified. Different natural plant species have been studied for mercury uptake, accumulation, toxicity and overall mercury removal efficiency. Various mercury compounds, such as HgS, HgCl{sub 2} and Hg(NO{sub 3}){sub 2}, were used as contaminant sources. Different types of soil were examined and chosen for phyto-remediation experiments. We have applied microscopy and diffuse reflectance spectrometry as well as conventional analytical chemistry to monitor the phyto-remediation processes of mercury uptake, translocation and accumulation; and the physiological impact of mercury contaminants on selected plant species. Our results indicate that certain plant species, such as beard grass (Polypogon monospeliensis), accumulated a very limited amount of mercury in the shoots (<65 mg/kg), even though root mercury accumulation is significant (maximum 2298 mg

  19. Prospects for tuberculosis elimination.

    PubMed

    Dye, Christopher; Glaziou, Philippe; Floyd, Katherine; Raviglione, Mario

    2013-01-01

    The target for TB elimination is to reduce annual incidence to less than one case per million population by 2050. Meeting that target requires a 1,000-fold reduction in incidence in little more than 35 years. This can be achieved only by combining the effective treatment of active TB-early case detection and high cure rates to interrupt transmission-with methods to prevent new infections and to neutralize existing latent infections. Vigorous implementation of the WHO Stop TB Strategy is needed to achieve the former, facilitated by the effective supply of, and demand for, health services. The latter calls for new technology, including biomarkers of TB risk, diagnostics, drugs, and vaccines. An important milestone en route to elimination will be reached when there is less than 1 TB death per 100,000 population, marking entry into the elimination phase. This landmark can be reached by many countries within 1-2 decades. PMID:23244049

  20. Gas-phase mercury reduction to measure total mercury in the flue gas of a coal-fired boiler.

    PubMed

    Meischen, Sandra J; Van Pelt, Vincent J; Zarate, Eugene A; Stephens, Edward A

    2004-01-01

    Gaseous elemental and total (elemental + oxidized) mercury (Hg) in the flue gas from a coal-fired boiler was measured by a modified ultraviolet (UV) spectrometer. Challenges to Hg measurement were the spectral interferences from other flue gas components and that UV measures only elemental Hg. To eliminate interference from flue gas components, a cartridge filled with gold-coated sand removed elemental Hg from a flue gas sample. The Hg-free flue gas was the reference gas, eliminating the spectral interferences. To measure total Hg by UV, oxidized Hg underwent a gas-phase, thermal-reduction in a quartz cell heated to 750 degrees C. Simultaneously, hydrogen was added to flash react with the oxygen present forming water vapor and preventing Hg re-oxidation as it exits the cell. Hg concentration results are in parts per billion by volume Hg at the flue gas oxygen concentration. The modified Hg analyzer and the Ontario Hydro method concurrently measured Hg at a field test site. Measurements were made at a 700-MW steam turbine plant with scrubber units and selective catalytic reduction. The flue gas sampled downstream of the selective catalytic reduction contained 2100 ppm SO2 and 75 ppm NOx. Total Hg measured by the Hg analyzer was within 20% of the Ontario Hydro results. PMID:14871013

  1. Rescheduling the process of nanoparticle removal used for water mercury remediation can increase the risk to aquatic organism: evidence of innate immune functions modulation in European eel (Anguilla anguilla L.).

    PubMed

    Costa, Leonor C; Mohmood, Iram; Trindade, Tito; Saleem, Mohammad; Duarte, Armando C; Pereira, Eduarda; Ahmad, Iqbal

    2015-12-01

    This study aimed to assess the mechanisms of innate immune function responses to silica-coated iron oxide nanoparticle functionalized with dithiocarbamate groups (IONP) exposure alone and its associated mercury (Hg) in European eel (Anguilla anguilla L.) phagocytes isolated from peritoneum (P-phagocytes), gill (G-phagocytes), head kidney (HK-phagocytes) and spleen (S-phagocytes). The study evaluated viability, phagocytosis, oxidative burst activity (OBA) and lipid peroxidation (LPO). Four groups were made: (1) 2 × 10(6) phagocytes + RPMI-1640 (control), (2) 2 × 10(6) phagocytes + IONP (2.5 mg L(-1)), (3) 2 × 10(6) phagocytes + Hg (50 μg L(-1)) and (4) 2 × 10(6) phagocytes + IONP + Hg. Samplings were performed at 0, 2, 4, 8, 16, 24, 48 and 72 h of exposure. A. anguilla P-, G-, HK- and S-phagocytes in vitro exposure to IONP alone revealed either increased (except HK-phagocytes at 16 h) or no change in viability, suggesting that the cells are metabolically active and resistant to IONP exposure alone. In terms of phagocytes overactivation and reactive oxygen species (ROS) production as an indirect mechanism of immunotoxicity, the phagocytes responded in the following manner: P- > S- > HK- = G-phagocytes for IONP exposure alone, S- > HK- > P- = G-phagocytes for Hg exposure alone and HK- > G- = S- > P-phagocytes for concomitant exposure. Overall, considering Hg as a surrogate for metals and its association with IONP, as well as the likelihood that it could pose a serious threat to aquatic organisms by modulating their immune defense mechanisms if accidentally discharged into the aquatic environment, current results suggest that the step of IONP-metal complex removal must not be underrated and should be processed without any more ado. PMID:26396010

  2. Investigation of mercury thruster isolators. [service life

    NASA Technical Reports Server (NTRS)

    Mantenieks, M. A.

    1973-01-01

    Mercury ion thruster isolator lifetime tests were performed using different isolator materials and geometries. Tests were performed with and without the flow of mercury through the isolators in an oil diffusion pumped vacuum facility and cryogenically pumped bell jar. The onset of leakage current in isolators tested occurred in time intervals ranging from a few hours to many hundreds of hours. In all cases, surface contamination was responsible for the onset of leakage current and subsequent isolator failure. Rate of increase of leakage current and the leakage current level increased approximately exponentially with isolator temperature. Careful attention to shielding techniques and the elimination of sources of metal oxides appear to have eliminated isolator failures as a thruster life limiting mechanism.

  3. Elimination of Social Rules.

    ERIC Educational Resources Information Center

    O'Toole, Teddy

    The thesis of this document is that arbitrary social rules must be eliminated. Chapters cover: (1) what it is like to be a student whose personal activities are controlled; (2) the necessity of environmental freedom as a prerequisite to successful educational reform; (3) the question of environmental control; (4) the legal history of environmental…

  4. Minding Rachlin's Eliminative Materialism

    ERIC Educational Resources Information Center

    McDowell, J. J.

    2012-01-01

    Rachlin's teleological behaviorism eliminates the first-person ontology of conscious experience by identifying mental states with extended patterns of behavior, and thereby maintains the materialist ontology of science. An alternate view, informed by brain-based and externalist philosophies of mind, is shown also to maintain the materialist…

  5. Impact of sulfur oxides on mercury capture by activated carbon.

    PubMed

    Presto, Albert A; Granite, Evan J

    2007-09-15

    Recent field tests of mercury removal with activated carbon injection (ACI) have revealed that mercury capture is limited in flue gases containing high concentrations of sulfur oxides (SOx). In order to gain a more complete understanding of the impact of SOx on ACl, mercury capture was tested under varying conditions of SO2 and SO3 concentrations using a packed bed reactor and simulated flue gas (SFG). The final mercury content of the activated carbons is independent of the SO2 concentration in the SFG, but the presence of SO3 inhibits mercury capture even at the lowest concentration tested (20 ppm). The mercury removal capacity decreases as the sulfur content of the used activated carbons increases from 1 to 10%. In one extreme case, an activated carbon with 10% sulfur, prepared by H2SO4 impregnation, shows almost no mercury capacity. The results suggest that mercury and sulfur oxides are in competition for the same binding sites on the carbon surface. PMID:17948811

  6. The capture of oxidized mercury from simulated desulphurization aqueous solutions.

    PubMed

    Ochoa-González, Raquel; Díaz-Somoano, Mercedes; Martínez-Tarazona, M Rosa

    2013-05-15

    Elemental mercury in flue gases from coal combustion is difficult to control. However, oxidized mercury species are soluble in water and can be removed with a high degree of efficiency in wet flue gas desulphurization (WFGD) systems operating in coal combustion plants, provided that no re-emissions occur. In this article the mechanisms affecting the re-emission of oxidized mercury species in WFGD conditions via sulphite ions are discussed. The parameters studied include the operating temperature, the pH, the redox potential, the concentrations of mercury and oxygen in the flue gas and the concentration of reductive ions in the solution. The results show that temperature, pH and the concentration of mercury at the inlet of the WFGD systems are the most important factors affecting oxidized mercury removal. The results indicate that sulphite ions, not only contribute to the reduction of Hg(2+), but that they may also stabilize the mercury in the liquid fraction of the WFGD limestone slurry. Consequently, factors that increase the sulphite content in the slurry such as a low oxygen concentration promote the co-capture of mercury with sulphur. PMID:23500649

  7. Impact of sulfur oxides on mercury capture by activated carbon

    SciTech Connect

    Albert A. Presto; Evan J. Granite

    2007-09-15

    Recent field tests of mercury removal with activated carbon injection (ACI) have revealed that mercury capture is limited in flue gases containing high concentrations of sulfur oxides (SOx). In order to gain a more complete understanding of the impact of SOx on ACI, mercury capture was tested under varying conditions of SO{sub 2} and SO{sub 3} concentrations using a packed bed reactor and simulated flue gas (SFG). The final mercury content of the activated carbons is independent of the SO{sub 2} concentration in the SFG, but the presence of SO{sub 3} inhibits mercury capture even at the lowest concentration tested (20 ppm). The mercury removal capacity decreases as the sulfur content of the used activated carbons increases from 1 to 10%. In one extreme case, an activated carbon with 10% sulfur, prepared by H{sub 2}SO{sub 4} impregnation, shows almost no mercury capacity. The results suggest that mercury and sulfur oxides are in competition for the same binding sites on the carbon surface. 30 refs., 3 figs., 2 tabs.

  8. In situ mercury stabilization

    SciTech Connect

    Fuhrmann, M.; Kalb, P.; Adams, J.

    2004-09-01

    BNL Royalty Project Internal Status Report. The funds from the allotment of royalty income were used to experimentally explore feasibility of related, potential new techniques based on the Environmental Sciences Department successful technology licensed for the ex situ treatment of mercury. Specifically, this work is exploring the concept of using Sulfur Polymer Cement (SPC) in an in situ application to stabilize and/or remove mercury (Hg) from surficial soil. Patent disclosure forms have been filed for this process. Soil was artificially spiked with 500 ppm Hg and a series of experiments were set up in which SPC rods were placed in the center of a mass of this soil. Some experiments were conducted at 20 C and others at 50 C. After times ranging from 11 to 24 days, these experiments were opened, photographed and the soil was sampled from discrete locations in the containers. The soil and SPC samples were analyzed for Fe and Hg by x-ray fluorescence. The Hg profile in the soil was significantly altered, with concentrations along the outer edge of the soil reduced by as much as 80% from the starting concentration. Conversely, closer to the treatment rod containing SPC, concentrations of Hg were significantly increased over the original concentration. Preliminary results for elevated temperature sample are shown graphically in Figure 2. Apparently the Hg had migrated toward the SPC and reacted with sulfur to form Hg S. This appears to be a reaction between gaseous phases of both S and Hg, with Hg having a greater vapor pressure. The concentration of low solubility HgS (i.e., low leaching properties) developed within 11 days at 50 C and 21 days at 20 C, confirming the potential of this concept.

  9. Emissions of airborne toxics from coal-fired boilers: Mercury

    SciTech Connect

    Huang, H.S.; Livengood, C.D.; Zaromb, S.

    1991-09-01

    Concerns over emissions of hazardous air Pollutants (air toxics) have emerged as a major environmental issue, and the authority of the US Environmental Protection Agency to regulate such pollutants was greatly expanded through the Clean Air Act Amendments of 1990. Mercury has been singled out for particular attention because of concerns over possible effects of emissions on human health. This report evaluates available published information on the mercury content of coals mined in the United States, on mercury emitted in coal combustion, and on the efficacy of various environmental control technologies for controlling airborne emissions. Anthracite and bituminous coals have the highest mean-mercury concentrations, with subbituminous coals having the lowest. However, all coal types show very significant variations in mercury concentrations. Mercury emissions from coal combustion are not well-characterized, particularly with regard to determination of specific mercury compounds. Variations in emission rates of more than an order of magnitude have been reported for some boiler types. Data on the capture of mercury by environmental control technologies are available primarily for systems with electrostatic precipitators, where removals of approximately 20% to over 50% have been reported. Reported removals for wet flue-gas-desulfurization systems range between 35 and 95%, while spray-dryer/fabric-filter systems have given removals of 75 to 99% on municipal incinerators. In all cases, better data are needed before any definitive judgments can be made. This report briefly reviews several areas of research that may lead to improvements in mercury control for existing flue-gas-clean-up technologies and summarizes the status of techniques for measuring mercury emissions from combustion sources.

  10. Phytoremediation of Ionic and Methyl Mercury P

    SciTech Connect

    Meagher, Richard B.

    1999-06-01

    transgenic plants expressing the bacterial merB and merA genes will (a) remove mercury from polluted soil and water and (b) prevent methylmercury from entering the food chain. Our specific aims center on understanding the mechanisms by which plants process the various forms of mercury and volatilize or transpire mercury vapor. This information will allow us to improve the design of our current phytoremediation strategies. As an alternative to volatilizing mercury, we are using several new genes to construct plants that will hyperaccumulate mercury in above-ground tissues for later harvest. The Department of Energy's Oak Ridge National Laboratory and Brookhaven National Laboratory have sites with significant levels of mercury contamination that could be cleaned by applying the scientific discoveries and new phytoremediation technologies described in this proposal. The knowledge and expertise gained by engineering plants to hyperaccumulate mercury can be applied to the remediation of other heavy metals pollutants (e.g., arsenic, cesium, cadmium, chromium, lead, strontium, technetium, uranium) found at several DOE facilities.

  11. Demonstration of Mer-Cure Technology for Enhanced Mercury Control

    SciTech Connect

    John Marion; Dave O'Neill; Kevin Taugher; Shin Kang; Mark Johnson; Gerald Pargac; Jane Luedecke; Randy Gardiner; Mike Silvertooth; Jim Hicks; Carl Edberg; Ray Cournoyer; Stanley Bohdanowicz; Ken Peterson; Kurt Johnson; Steve Benson; Richard Schulz; Don McCollor; Mike Wuitshick

    2008-06-01

    Alstom Power Inc. has completed a DOE/NETL-sponsored program (under DOE Cooperative Agreement No. De-FC26-07NT42776) to demonstrate Mer-Cure{trademark}, one of Alstom's mercury control technologies for coal-fired boilers. The Mer-Cure{trademark}system utilizes a small amount of Mer-Clean{trademark} sorbent that is injected into the flue gas stream for oxidation and adsorption of gaseous mercury. Mer-Clean{trademark} sorbents are carbon-based and prepared with chemical additives that promote oxidation and capture of mercury. The Mer-Cure{trademark} system is unique in that the sorbent is injected into an environment where the mercury capture kinetics is accelerated. The full-scale demonstration program originally included test campaigns at two host sites: LCRA's 480-MW{sub e} Fayette Unit No.3 and Reliant Energy's 190-MW{sub e} Shawville Unit No.3. The only demonstration tests actually done were the short-term tests at LCRA due to budget constraints. This report gives a summary of the demonstration testing at Fayette Unit No.3. The goals for this Mercury Round 3 program, established by DOE/NETL under the original solicitation, were to reduce the uncontrolled mercury emissions by 90% at a cost significantly less than 50% of the previous target of $60,000/lb mercury removed. The results indicated that Mer-Cure{trademark} technology could achieve mercury removal of 90% based on uncontrolled stack emissions. The estimated costs for 90% mercury control, at a sorbent cost of $0.75 to $2.00/lb respectively, were $13,400 to $18,700/lb Hg removed. In summary, the results from demonstration testing show that the goals established by DOE/NETL were met during this test program. The goal of 90% mercury reduction was achieved. Estimated mercury removal costs were 69-78% lower than the benchmark of $60,000/lb mercury removed, significantly less than 50% of the baseline removal cost.

  12. Antarctic winter mercury and ozone depletion events over sea ice

    NASA Astrophysics Data System (ADS)

    Nerentorp Mastromonaco, M.; Gårdfeldt, K.; Jourdain, B.; Abrahamsson, K.; Granfors, A.; Ahnoff, M.; Dommergue, A.; Méjean, G.; Jacobi, H.-W.

    2016-03-01

    During atmospheric mercury and ozone depletion events in the springtime in polar regions gaseous elemental mercury and ozone undergo rapid declines. Mercury is quickly transformed into oxidation products, which are subsequently removed by deposition. Here we show that such events also occur during Antarctic winter over sea ice areas, leading to additional deposition of mercury. Over four months in the Weddell Sea we measured gaseous elemental, oxidized, and particulate-bound mercury, as well as ozone in the troposphere and total and elemental mercury concentrations in snow, demonstrating a series of depletion and deposition events between July and September. The winter depletions in July were characterized by stronger correlations between mercury and ozone and larger formation of particulate-bound mercury in air compared to later spring events. It appears that light at large solar zenith angles is sufficient to initiate the photolytic formation of halogen radicals. We also propose a dark mechanism that could explain observed events in air masses coming from dark regions. Br2 that could be the main actor in dark conditions was possibly formed in high concentrations in the marine boundary layer in the dark. These high concentrations may also have caused the formation of high concentrations of CHBr3 and CH2I2 in the top layers of the Antarctic sea ice observed during winter. These new findings show that the extent of depletion events is larger than previously believed and that winter depletions result in additional deposition of mercury that could be transferred to marine and terrestrial ecosystems.

  13. Mercury in pheasant (Phasianus colchicus) organs in Podravina, Croatia.

    PubMed

    Spirić, Zdravko; Srebočan, Emil; Crnić, Andreja Prevendar

    2013-01-01

    Since 1995 the concentrations of total mercury were analyzed in the pheasant organs (liver, kidney, brain and muscle) that live freely in an area that was exposed to elevated levels of mercury as a result of industrial activity (mercury contaminated natural gas production and processing which began in 1980). The range of the median mercury concentration values (wet weight) in pheasant organs in Podravina, Croatia were 0.0004-0.024, 0.0001-0.034, 0.0002-0.016 and 0.0001-0.025 μg/g for liver, kidney, brain, and muscle, respectively. Results of these studies confirms that in the study area in the observed period there was no significant mercury contamination which can be linked to anthropogenic activities (hydrocarbon production)‥ On the contrary, systematic measurements demonstrate a small but constant (barely noticeable) decline in mercury concentrations in pheasant's organs. Primarily, this is the result of the significant improvement in the technological process which involves the removal of mercury from the natural gas that was designed and implemented in 1993. However, due to the need for reliable control of mercury contaminated natural gas production and the importance for better understanding of long-term exposure to low levels of mercury, and assessment of their possible harmful effects on the environment, human and animal health, research will be continued. PMID:23379943

  14. The release, tissue distribution and excretion of mercury from experimental amalgam tattoos.

    PubMed Central

    Cox, S. W.; Eley, B. M.

    1986-01-01

    Following the subcutaneous implantation of powdered dental amalgam in guinea pigs, there was an initial extrusion of material from the healing implantation wounds. Longer-term release of mercury from the lesions was demonstrated by linear regression analysis of the mercury contents of implant sites removed after time periods of up to 2 years. Raised mercury levels were detected in the blood, bile, kidneys, liver, spleen and lungs of implanted animals; by far the highest concentrations were found in the renal cortex. Mercury was excreted with the urine and, to a lesser extent, the faeces. The pattern of mercury redistribution resembled that seen following chronic exposure to mercuric compounds. PMID:3801303

  15. Demystifying the selection of mist eliminators

    SciTech Connect

    Fabian, P.; Cusack, R.; Hennessey, P.; Neuman, M. )

    1993-11-01

    In any process where gases and liquids come in intimate contact, mists are generated by the entrainment of liquid droplets into the gas streams. The formation of such mists often results in process inefficiencies and product loss in evaporators, knockout drums, distillation columns, and environmental scrubbers. Besides, these mists can cause serious damage to rotating equipment. hence the need to know how best to remove the liquid droplets from a misty gas stream. Today, one can select from many classes of equipment, known as mist eliminators or entrainment separators, designed to remove the liquid droplets along with any solid particles from the gas stream. Before arriving at a selection, one must weigh several important factors: The sizes of droplets that the separator must remove; The pressure drop that can be tolerated in achieving the required level of mist removal; Susceptibility of the separator to plugging by solids, if solids are present; Liquid handling capability of the separator; Whether the mist eliminator can be installed inside existing equipment, or if it requires a stand alone vessel instead; The availability of the materials of construction that are compatible with the process; and Costs of the mists eliminator itself and other required vessels, piping, instrumentation, and utilities.

  16. Process for removal of hazardous air pollutants from coal

    DOEpatents

    Akers, David J.; Ekechukwu, Kenneth N.; Aluko, Mobolaji E.; Lebowitz, Howard E.

    2000-01-01

    An improved process for removing mercury and other trace elements from coal containing pyrite by forming a slurry of finely divided coal in a liquid solvent capable of forming ions or radicals having a tendency to react with constituents of pyrite or to attack the bond between pyrite and coal and/or to react with mercury to form mercury vapors, and heating the slurry in a closed container to a temperature of at least about 50.degree. C. to produce vapors of the solvent and withdrawing vapors including solvent and mercury-containing vapors from the closed container, then separating mercury from the vapors withdrawn.

  17. Marine biogeochemistry of mercury

    SciTech Connect

    Gill, G.A.

    1986-01-01

    Noncontaminating sample collection and handling procedures and accurate and sensitive analysis methods were developed to measure sub-picomolar Hg concentrations in seawater. Reliable and diagnostic oceanographic Hg distributions were obtained, permitting major processes governing the marine biogeochemistry of Hg to be identified. Mercury concentrations in the northwest Atlantic, central Pacific, southeast Pacific, and Tasman Sea ranged from 0.5 to 12 pM. Vertical Hg distributions often exhibited a maximum within or near the main thermocline. At similar depths, Hg concentrations in the northwest Atlantic Ocean were elevated compared to the N. Pacific Ocean. This pattern appears to result from a combination of enhanced supply of Hg to the northwest Atlantic by rainfall and scavenging removal along deep water circulation pathways. These observations are supported by geochemical steady-state box modelling which predicts a relatively short mean residence time for Hg in the oceans; demonstrating the reactive nature of Hg in seawater and precluding significant involvement in nutrient-type recyclic. Evidence for the rapid removal of Hg from seawater was obtained at two locations. Surface seawater Hg measurements along 160/sup 0/ W (20/sup 0/N to 20/sup 0/S) showed a depression in the equatorial upwelling area which correlated well with the transect region exhibiting low /sup 234/Th//sup 238/U activity ratios. This relationship implies that Hg will be scavenged and removed from surface seawater in biologically productive oceanic zones. Further, a broad minimum in the vertical distribution of Hg was observed to coincide with the intense oxygen minimum zone in the water column in coastal waters off Peru.

  18. Fate and aqueous transport of mercury in light of the Clean Air Mercury Rule for coal-fired electric power plants

    NASA Astrophysics Data System (ADS)

    Arzuman, Anry

    Mercury is a hazardous air pollutant emitted to the atmosphere in large amounts. Mercury emissions from electric power generation sources were estimated to be 48 metric tons/year, constituting the single largest anthropogenic source of mercury in the U.S. Settled mercury species are highly toxic contaminants of the environment. The newly issued Federal Clean Air Mercury Rule requires that the electric power plants firing coal meet the new Maximum Achievable Mercury Control Technology limit by 2018. This signifies that all of the air-phase mercury will be concentrated in solid phase which, based on the current state of the Air Pollution Control Technology, will be fly ash. Fly ash is utilized by different industries including construction industry in concrete, its products, road bases, structural fills, monifills, for solidification, stabilization, etc. Since the increase in coal combustion in the U.S. (1.6 percent/year) is much higher than the fly ash demand, large amounts of fly ash containing mercury and other trace elements are expected to accumulate in the next decades. The amount of mercury transferred from one phase to another is not a linear function of coal combustion or ash production, depends on the future states of technology, and is unknown. The amount of aqueous mercury as a function of the future removal, mercury speciation, and coal and aquifer characteristics is also unknown. This paper makes a first attempt to relate mercury concentrations in coal, flue gas, fly ash, and fly ash leachate using a single algorithm. Mercury concentrations in all phases were examined and phase transformation algorithms were derived in a form suitable for probabilistic analyses. Such important parameters used in the transformation algorithms as Soil Cation Exchange Capacity for mercury, soil mercury selectivity sequence, mercury activity coefficient, mercury retardation factor, mercury species soil adsorption ratio, and mercury Freundlich soil adsorption isotherm

  19. Mercury Report-Children's exposure to elemental mercury

    MedlinePlus

    ... PDF - 781KB] En Español [PDF - 6.6MB] What did ATSDR find? For children, most elemental mercury exposures ... that exposed children to elemental mercury. The report did not include a review of mercury exposures from ...

  20. Minding Rachlin's eliminative materialism.

    PubMed

    McDowell, J J

    2012-01-01

    Rachlin's teleological behaviorism eliminates the first-person ontology of conscious experience by identifying mental states with extended patterns of behavior, and thereby maintains the materialist ontology of science. An alternate view, informed by brain-based and externalist philosophies of mind, is shown also to maintain the materialist ontology of science, but without eliminating the phenomenology of consciousness. This view implies that to be judged human, machines not only must exhibit complicated temporally structured patterns of behavior, but also must have first-person conscious experience. Although confirming machine sentience is likely to be problematic, extended contact with a machine that results in a person interacting with it as if it were conscious could reasonably lead to the conclusion that for all intents and purposes it is. PMID:22942531

  1. Minding Rachlin's Eliminative Materialism

    PubMed Central

    McDowell, J.J

    2012-01-01

    Rachlin's teleological behaviorism eliminates the first-person ontology of conscious experience by identifying mental states with extended patterns of behavior, and thereby maintains the materialist ontology of science. An alternate view, informed by brain-based and externalist philosophies of mind, is shown also to maintain the materialist ontology of science, but without eliminating the phenomenology of consciousness. This view implies that to be judged human, machines not only must exhibit complicated temporally structured patterns of behavior, but also must have first-person conscious experience. Although confirming machine sentience is likely to be problematic, extended contact with a machine that results in a person interacting with it as if it were conscious could reasonably lead to the conclusion that for all intents and purposes it is. PMID:22942531

  2. Mercury Calibration System

    SciTech Connect

    John Schabron; Eric Kalberer; Joseph Rovani; Mark Sanderson; Ryan Boysen; William Schuster

    2009-03-11

    U.S. Environmental Protection Agency (EPA) Performance Specification 12 in the Clean Air Mercury Rule (CAMR) states that a mercury CEM must be calibrated with National Institute for Standards and Technology (NIST)-traceable standards. In early 2009, a NIST traceable standard for elemental mercury CEM calibration still does not exist. Despite the vacature of CAMR by a Federal appeals court in early 2008, a NIST traceable standard is still needed for whatever regulation is implemented in the future. Thermo Fisher is a major vendor providing complete integrated mercury continuous emissions monitoring (CEM) systems to the industry. WRI is participating with EPA, EPRI, NIST, and Thermo Fisher towards the development of the criteria that will be used in the traceability protocols to be issued by EPA. An initial draft of an elemental mercury calibration traceability protocol was distributed for comment to the participating research groups and vendors on a limited basis in early May 2007. In August 2007, EPA issued an interim traceability protocol for elemental mercury calibrators. Various working drafts of the new interim traceability protocols were distributed in late 2008 and early 2009 to participants in the Mercury Standards Working Committee project. The protocols include sections on qualification and certification. The qualification section describes in general terms tests that must be conducted by the calibrator vendors to demonstrate that their calibration equipment meets the minimum requirements to be established by EPA for use in CAMR monitoring. Variables to be examined include linearity, ambient temperature, back pressure, ambient pressure, line voltage, and effects of shipping. None of the procedures were described in detail in the draft interim documents; however they describe what EPA would like to eventually develop. WRI is providing the data and results to EPA for use in developing revised experimental procedures and realistic acceptance criteria based on

  3. Mercury: The World Closest to the Sun.

    ERIC Educational Resources Information Center

    Cordell, Bruce M.

    1984-01-01

    Discusses various topics related to the geology of Mercury including the origin of Mercury's magnetism, Mercury's motions, volcanism, scarps, and Mercury's violent birth and early life. Includes a table comparing Mercury's orbital and physical data to that of earth's. (JN)

  4. Preconceptional monitoring of mercury levels in hair and blood as a tool for minimizing associated reproductive risks.

    PubMed

    Neuman, Gal; Gareri, Joey; Koren, Gideon

    2014-12-01

    We describe the case of a 41-year-old woman, planning a pregnancy, who had a spontaneous abortion and subsequently was found to have high blood mercury levels. The source of high mercury was in her diet that contained fish as her main source of protein. Serial measurements of mercury in hair and blood allowed the team to determine the exact time when safe levels of mercury were reached, to eliminate elevated mercury levels as a potential cause of spontaneous abortion and to use preconception counseling to minimize the risk for adverse pregnancy outcome. PMID:24831651

  5. Task 2.8 - Mercury Speciation and Capture in Scubber Solutions

    SciTech Connect

    Sumitra R. Ness

    1997-08-01

    U.S. Environmental Protection Agency (EPA) investigation into health risks associated with mercury emissions from utility steam generators, municipal waste combustion units, and other sources was mandated by the Clean Air Act Amendments (CAAA) of 1990. In anticipation of mercury emission regulation, attention has been focused on quantification of mercury emissions, which require verifiable sampling and analytical techniques. Several sampling and analytical methods are currently under the final stages of development as well as a variety of emission control methods. In particular, wet scrubber systems designed for S2 control in coal-fired utilities have been targeted for mercury control. Conventional wet-scrubbers remove mercury in a variety of soluble oxidized forms. Oxidized mercury is highly water-soluble and can be removed by scrubber slurry, theoretically limited only by gas-film mass transfer. However, since some oxidized mercury forms such as HgClz are borh soluble and volatile, the final fate of mercury trapped in scrubber solutions is unclear. Elemental mercury is not water-soluble, remaining in the vapor state at temperatures through pollution control devices and exiting the stack into the environment. However, notable exceptions to this rule exist. Depending on the type of mercury-sampling method used, an increase ofs 10% in elemental mercury concentrations across wet scrubbers has been metiured but is yet unconllrmed. Also, significant amounts of elemental mercury (metallic form) have been removed during wet scrubber maintenance. In addition, questions concerning 1) the initial speciation between oxidized and elemental forms of mercury in flue gas from coal- fired boilers and 2) the effects of scrubber slurry composition and pH on the mercury species have been raised.

  6. Update of mercury emissions from China's primary zinc, lead and copper smelters, 2000-2010

    NASA Astrophysics Data System (ADS)

    Wu, Q. R.; Wang, S. X.; Zhang, L.; Song, J. X.; Yang, H.; Meng, Y.

    2012-07-01

    China is the largest anthropogenic mercury emitter in the world, where primary nonferrous metal smelting process is regarded as one of the most significant emission sources. In this study, atmospheric mercury emissions from primary zinc, lead and copper smelters in China during 2000-2010 were estimated using a technology-based methodology with comprehensive consideration of mercury concentration in concentrates, smelting process, mercury removal efficiencies of air pollution control devices (APCDs) and installation rate of a certain type of APCD combination. Our study indicated that atmospheric mercury emission from nonferrous metal smelters in 2000, 2003, 2005, 2007 and 2010 was 67.6, 100.1 86.7 80.6 and 72.5 t, respectively. In 2010, the mercury in metal concentrates consumed by primary zinc, lead and copper smelters were 543 t. The mercury emitted into atmosphere, fly ash, other solids, waste water and acid was 72.5, 61.5, 2.0, 3774 and 27.2 t, respectively. Mercury retrieved directly from flue gas as byproduct of nonferrous metal smelting was about 2.4 t. The amounts of mercury emitted into atmosphere were 39.4, 30.6 and 2.5 t from primary zinc, lead and copper smelters, respectively. The largest amount of mercury was emitted from Gansu province, followed by Henan, Yunnan, Hunan, Inner Mongolia and Shaanxi provinces. The average mercury removal efficiency was 90.5%, 71.2% and 91.8% in zinc, lead, and copper smelters, respectively.

  7. Mercury transformation and speciation in flue gases from anthropogenic emission sources: a critical review

    NASA Astrophysics Data System (ADS)

    Zhang, L.; Wang, S. X.; Wu, Q. R.; Wang, F. Y.; Lin, C.-J.; Zhang, L. M.; Hui, M. L.; Hao, J. M.

    2015-11-01

    Mercury transformation mechanisms and speciation profiles are reviewed for mercury formed in and released from flue gases of coal-fired boilers, non-ferrous metal smelters, cement plants, iron and steel plants, municipal solid waste incinerators, and biomass burning. Mercury in coal, ores and other raw materials is released to flue gases in the form of Hg0 during combustion or smelting in boilers, kilns or furnaces. Decreasing temperature from over 800 °C to below 300 °C in flue gases leaving boilers, kilns or furnaces promotes homogeneous and heterogeneous oxidation of gaseous elemental mercury (Hg0) to gaseous divalent mercury (Hg2+), with a portion of Hg2+ adsorbed onto fly ash to form particulate-bound mercury (Hgp). Halogen is the primary oxidizer for Hg0 in flue gases, and active components (e.g.,TiO2, Fe2O3, etc.) on fly ash promote heterogeneous oxidation and adsorption processes. In addition to mercury removal, mercury transformation also occurs when passing through air pollution control devices (APCDs), affecting the mercury speciation in flue gases. In coal-fired power plants, selective catalytic reduction (SCR) system promotes mercury oxidation by 34-85 %, electrostatic precipitator (ESP) and fabric filter (FF) remove over 99 % of Hgp, and wet flue gas desulfurization system (WFGD) captures 60-95 % of Hg2+. In non-ferrous metal smelters, most Hg0 is converted to Hg2+ and removed in acid plants (APs). For cement clinker production, mercury cycling and operational conditions promote heterogeneous mercury oxidation and adsorption. The mercury speciation profiles in flue gases emitted to the atmosphere are determined by transformation mechanisms and mercury removal efficiencies by various APCDs. For all the sectors reviewed in this study, Hgp accounts for less than 5 % in flue gases. In China, mercury emission has a higher fraction (66-82 % of total mercury) in flue gases from coal combustion, in contrast to a greater Hg2+ fraction (29-90 %) from non

  8. Mercury emission and speciation of coal-fired power plants in China

    NASA Astrophysics Data System (ADS)

    Wang, S. X.; Zhang, L.; Li, G. H.; Wu, Y.; Hao, J. M.; Pirrone, N.; Sprovieri, F.; Ancora, M. P.

    2010-02-01

    Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of Selective Catalytic Reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92-27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66-94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.

  9. Mercury emission and speciation of coal-fired power plants in China

    NASA Astrophysics Data System (ADS)

    Wang, S.; Zhang, L.; Li, G.; Wu, Y.; Hao, J.; Pirrone, N.; Sprovieri, F.; Ancora, M. P.

    2009-11-01

    Comprehensive field measurements are needed to understand the mercury emissions from Chinese power plants and to improve the accuracy of emission inventories. Characterization of mercury emissions and their behavior were measured in six typical coal-fired power plants in China. During the tests, the flue gas was sampled simultaneously at inlet and outlet of selective catalyst reduction (SCR), electrostatic precipitators (ESP), and flue gas desulfurization (FGD) using the Ontario Hydro Method (OHM). The pulverized coal, bottom ash, fly ash and gypsum were also sampled in the field. Mercury concentrations in coal burned in the measured power plants ranged from 17 to 385 μg/kg. The mercury mass balances for the six power plants varied from 87 to 116% of the input coal mercury for the whole system. The total mercury concentrations in the flue gas from boilers were at the range of 1.92-27.15 μg/m3, which were significantly related to the mercury contents in burned coal. The mercury speciation in flue gas right after the boiler is influenced by the contents of halogen, mercury, and ash in the burned coal. The average mercury removal efficiencies of ESP, ESP plus wet FGD, and ESP plus dry FGD-FF systems were 24%, 73% and 66%, respectively, which were similar to the average removal efficiencies of pollution control device systems in other countries such as US, Japan and South Korea. The SCR system oxidized 16% elemental mercury and reduced about 32% of total mercury. Elemental mercury, accounting for 66-94% of total mercury, was the dominant species emitted to the atmosphere. The mercury emission factor was also calculated for each power plant.

  10. Adsorbents for capturing mercury in coal-fired boiler flue gas.

    PubMed

    Yang, Hongqun; Xu, Zhenghe; Fan, Maohong; Bland, Alan E; Judkins, Roddie R

    2007-07-19

    This paper reviews recent advances in the research and development of sorbents used to capture mercury from coal-fired utility boiler flue gas. Mercury emissions are the source of serious health concerns. Worldwide mercury emissions from human activities are estimated to be 1000 to 6000 t/annum. Mercury emissions from coal-fired power plants are believed to be the largest source of anthropogenic mercury emissions. Mercury emissions from coal-fired utility boilers vary in total amount and speciation, depending on coal types, boiler operating conditions, and configurations of air pollution control devices (APCDs). The APCDs, such as fabric filter (FF) bag house, electrostatic precipitator (ESP), and wet flue gas desulfurization (FGD), can remove some particulate-bound and oxidized forms of mercury. Elemental mercury often escapes from these devices. Activated carbon injection upstream of a particulate control device has been shown to have the best potential to remove both elemental and oxidized mercury from the flue gas. For this paper, NORIT FGD activated carbon was extensively studied for its mercury adsorption behavior. Results from bench-, pilot- and field-scale studies, mercury adsorption by coal chars, and a case of lignite-burned mercury control were reviewed. Studies of brominated carbon, sulfur-impregnated carbon and chloride-impregnated carbon were also reviewed. Carbon substitutes, such as calcium sorbents, petroleum coke, zeolites and fly ash were analyzed for their mercury-adsorption performance. At this time, brominated activated carbon appears to be the best-performing mercury sorbent. A non-injection regenerable sorbent technology is briefly introduced herein, and the issue of mercury leachability is briefly covered. Future research directions are suggested. PMID:17544578

  11. Modeling dynamic exchange of gaseous elemental mercury at polar sunrise.

    PubMed

    Dastoor, Ashu P; Davignon, Didier; Theys, Nicolas; Van Roozendael, Michel; Steffen, Alexandra; Ariya, Parisa A

    2008-07-15

    At polar sunrise, gaseous elemental mercury (GEM) undergoes an exceptional dynamic exchange in the air and at the snow surface during which GEM can be rapidly removed from the atmosphere (the so-called atmospheric mercury depletion events (AMDEs)) as well as re-emitted from the snow within a few hours to days in the Polar Regions. Although high concentrations of total mercury in snow following AMDEs is well documented, there is very little data available on the redox transformation processes of mercury in the snow and the fluxes of mercury at the air/snow interface. Therefore, the net gain of mercury in the Polar Regions as a result of AMDEs is still an open question. We developed a new version of the global mercury model, GRAHM, which includes for the first time bidirectional surface exchange of GEM in Polar Regions in spring and summer by developing schemes for mercury halogen oxidation, deposition, and re-emission. Also for the first time, GOME satellite data-derived boundary layer concentrations of BrO have been used in a global mercury model for representation of halogen mercury chemistry. Comparison of model simulated and measured atmospheric concentrations of GEM at Alert, Canada, for 3 years (2002-2004) shows the model's capability in simulating the rapid cycling of mercury during and after AMDEs. Brooks et al. (1) measured mercury deposition, reemission, and net surface gain fluxes of mercury at Barrow, AK, during an intensive measurement campaign for a 2 week period in spring (March 25 to April 7, 2003). They reported 1.7, 1.0 +/- 0.2, and 0.7 +/- 0.2 microg m(-2) deposition, re-emission, and net surface gain, respectively. Using the optimal configuration of the model, we estimated 1.8 microg m(-2) deposition, 1.0 microg m(-2) re-emission, and 0.8 microg m(-2) net surface gain of mercury for the same time period at Barrow. The estimated net annual accumulation of mercury within the Arctic Circle north of 66.5 degrees is approximately 174 t with +/-7 t of

  12. Substorms on Mercury?

    NASA Technical Reports Server (NTRS)

    Siscoe, G. L.; Ness, N. F.; Yeates, C. M.

    1974-01-01

    Qualitative similarities between some of the variations in the Mercury encounter data and variations in the corresponding regions of the earth's magnetosphere during substorms are pointed out. The Mariner 10 data on Mercury show a strong interaction between the solar wind and the plant similar to a scaled down version of that for the earth's magnetosphere. Some of the features observed in the night side Mercury magnetosphere suggest time dependent processes occurring there.

  13. Phytoremediation of ionic and methyl mercury pollution

    SciTech Connect

    Meagher, R.B.

    1998-06-01

    'The long-term objective of the research is to manipulate single-gene traits into plants, enabling them to process heavy metals and remediate heavy-metal pollution by resistance, sequestration, removal, and management of these contaminants. The authors are focused on mercury pollution as a case study of this plant genetic engineering approach. The working hypothesis behind this proposal was that transgenic plants expressing both the bacterial organo mercury lyase (merB) and the mercuric ion reductase gene (merA) will: (A) remove the mercury from polluted sites and (B) prevent methyl mercury from entering the food chain. The results from the research are so positive that the technology will undoubtedly be applied in the very near future to cleaning large mercury contaminates sites. Many such sites were not remediable previously due to the excessive costs and the negative environmental impact of conventional mechanical-chemical technologies. At the time this grant was awarded 20 months ago, the authors had successfully engineered a small model plant, Arabidopsis thaliana, to use a highly modified bacterial mercuric ion reductase gene, merA9, to detoxify ionic mercury (Hg(II)), reducing it to much less toxic and volatile metallic Hg(0) (Rugh et al., 1996). Seeds from these plants germinate, grow, and set seed at normal growth rates on levels of Hg(II) that are lethal to normal plants. In assays on transgenic seedlings suspended in a solution of Hg(II), 10 ng of Hg(0) was evolved per min per mg wet weight of plant tissue. At that time, the authors had no information on expression of merA in any other plant species, nor had the authors tested merB in any plant. However, the results were so startlingly positive and well received that they clearly presaged a paradigm shift in the field of environmental remediation.'

  14. Mercury - the hollow planet

    NASA Astrophysics Data System (ADS)

    Rothery, D. A.

    2012-04-01

    Mercury is turning out to be a planet characterized by various kinds of endogenous hole (discounting impact craters), which are compared here. These include volcanic vents and collapse features on horizontal scales of tens of km, and smaller scale depressions ('hollows') associated with bright crater-floor deposits (BCFD). The BCFD hollows are tens of metres deep and kilometres or less across and are characteristically flat-floored, with steep, scalloped walls. Their form suggests that they most likely result from removal of surface material by some kind of mass-wasting process, probably associated with volume-loss caused by removal (via sublimation?) of a volatile component. These do not appear to be primarily a result of undermining. Determining the composition of the high-albedo bluish surface coating in BCFDs will be a key goal for BepiColombo instruments such as MIXS (Mercury Imaging Xray Spectrometer). In contrast, collapse features are non-circular rimless pits, typically on crater floors (pit-floor craters), whose morphology suggests collapse into void spaces left by magma withdrawal. This could be by drainage of either erupted lava (or impact melt) or of shallowly-intruded magma. Unlike the much smaller-scale BCFD hollows, these 'collapse pit' features tend to lack extensive flat floors and instead tend to be close to triangular in cross-section with inward slopes near to the critical angle of repose. The different scale and morphology of BCFD hollows and collapse pits argues for quite different modes of origin. However, BCFD hollows adjacent to and within the collapse pit inside Scarlatti crater suggest that the volatile material whose loss was responsible for the growth of the hollows may have been emplaced in association with the magma whose drainage caused the main collapse. Another kind of volcanic collapse can be seen within a 25 km-wide volcanic vent outside the southern rim of the Caloris basin (22.5° N, 146.1° E), on a 28 m/pixel MDIS NAC image

  15. Poultry manure as raw material for mercury adsorbents in gas applications

    SciTech Connect

    Klasson, K.T.; Lima, I.M.; Boihem, L.L.

    2009-09-30

    The quantity of poultry manure generated each year is large, and technologies that take advantage of the material should be explored. At the same time, increased emphasis on the reduction of mercury emissions from coal-fired electric power plants has resulted in environmental regulations that may, in the future, require application of activated carbons as mercury sorbents. The sorbents could be injected into the flue gas stream, where they could adsorb the mercury. The sorbents (now containing mercury) would be removed via filtration or other means from the flue gas. Our preliminary work has demonstrated that activated carbon made from poultry manure can adsorb mercury from air with good efficiency. In laboratory experiments, an activated carbon made from turkey cake manure removed the majority of elemental mercury from a hot air stream. Other activated carbons made from chicken and turkey litter manure were also efficient. In general, unwashed activated carbons made from poultry manure were more efficient in removing mercury than their acid-washed counterparts. The results suggest that the adsorption of mercury was mainly due to chemisorption on the surface of the carbon. Other potential uses for the activated carbons are the removal of mercury from air and natural gas.

  16. Eliminate the "Bounce"!

    ERIC Educational Resources Information Center

    Leigh, Susan

    2016-01-01

    The "bounce" (coined by students at Susan Leigh's last campus) refers to the amount of time students spent chasing signatures and removing often-unnecessary registration "holds" in order to attend their classes. Leigh explains that all this chaos from complex, separately housed transactional business processes has led to the…

  17. Peru Mercury Inventory 2006

    USGS Publications Warehouse

    Brooks, William E.; Sandoval, Esteban; Yepez, Miguel A.; Howard, Howell

    2007-01-01

    In 2004, a specific need for data on mercury use in South America was indicated by the United Nations Environmental Programme-Chemicals (UNEP-Chemicals) at a workshop on regional mercury pollution that took place in Buenos Aires, Argentina. Mercury has long been mined and used in South America for artisanal gold mining and imported for chlor-alkali production, dental amalgam, and other uses. The U.S. Geological Survey (USGS) provides information on domestic and international mercury production, trade, prices, sources, and recycling in its annual Minerals Yearbook mercury chapter. Therefore, in response to UNEP-Chemicals, the USGS, in collaboration with the Economic Section of the U.S. Embassy, Lima, has herein compiled data on Peru's exports, imports, and byproduct production of mercury. Peru was selected for this inventory because it has a 2000-year history of mercury production and use, and continues today as an important source of mercury for the global market, as a byproduct from its gold mines. Peru is a regional distributor of imported mercury and user of mercury for artisanal gold mining and chlor-alkali production. Peruvian customs data showed that 22 metric tons (t) of byproduct mercury was exported to the United States in 2006. Transshipped mercury was exported to Brazil (1 t), Colombia (1 t), and Guyana (1 t). Mercury was imported from the United States (54 t), Spain (19 t), and Kyrgyzstan (8 t) in 2006 and was used for artisanal gold mining, chlor-alkali production, dental amalgam, or transshipment to other countries in the region. Site visits and interviews provided information on the use and disposition of mercury for artisanal gold mining and other uses. Peru also imports mercury-containing batteries, electronics and computers, fluorescent lamps, and thermometers. In 2006, Peru imported approximately 1,900 t of a wide variety of fluorescent lamps; however, the mercury contained in these lamps, a minimum of approximately 76 kilograms (kg), and in

  18. Glutathione enzyme and selenoprotein polymorphisms associate with mercury biomarker levels in Michigan dental professionals.

    PubMed

    Goodrich, Jaclyn M; Wang, Yi; Gillespie, Brenda; Werner, Robert; Franzblau, Alfred; Basu, Niladri

    2011-12-01

    Mercury is a potent toxicant of concern to both the general public and occupationally exposed workers (e.g., dentists). Recent studies suggest that several genes mediating the toxicokinetics of mercury are polymorphic in humans and may influence inter-individual variability in mercury accumulation. This work hypothesizes that polymorphisms in key glutathione synthesizing enzyme, glutathione S-transferase, and selenoprotein genes underlie inter-individual differences in mercury body burden as assessed by analytical mercury measurement in urine and hair, biomarkers of elemental mercury and methylmercury, respectively. Urine and hair samples were collected from a population of dental professionals (n=515), and total mercury content was measured. Average urine (1.06±1.24 microg/L) and hair mercury levels (0.49±0.63 microg/g) were similar to national U.S. population averages. Taqman assays were used to genotype DNA from buccal swab samples at 15 polymorphic sites in genes implicated in mercury metabolism. Linear regression modeling assessed the ability of polymorphisms to modify the relationship between mercury biomarker levels and exposure sources (e.g., amalgams, fish consumption). Five polymorphisms were significantly associated with urine mercury levels (GSTT1 deletion), hair mercury levels (GSTP1-105, GSTP1-114, GSS 5'), or both (SEPP1 3'UTR). Overall, this study suggests that polymorphisms in selenoproteins and glutathione-related genes may influence elimination of mercury in the urine and hair or mercury retention following exposures to elemental mercury (via dental amalgams) and methylmercury (via fish consumption). PMID:21967774

  19. Evaluation of a sequential extraction process used for determining mercury binding mechanisms to coal combustion byproducts

    SciTech Connect

    James D. Noel; Pratim Biswas; Daniel E. Giammar

    2007-07-15

    This study evaluated the selectivity and effectiveness of a sequential extraction process used to determine mercury binding mechanisms to various materials that are present in coal combustion byproducts. A six-step sequential extraction process was applied to laboratory-synthesized materials with known mercury concentrations and binding mechanisms. These materials were calcite, hematite, goethite, and titanium dioxide. Fly ash from a full-scale coal-fired power plant was also investigated. The concentrations of mercury were measured using inductively coupled plasma (ICP) mass spectrometry, whereas the major elements were measured by ICP atomic emission spectrometry. The materials were characterized by X-ray powder diffraction and scanning electron microscopy with energy dispersive spectroscopy. The sequential extraction procedure provided information about the solid phases with which mercury was associated in the solid sample. The procedure effectively extracted mercury from the target phases. The procedure was generally selective in extracting mercury. However, some steps in the procedure extracted mercury from nontarget phases, and others resulted in mercury redistribution. Iron from hematite and goethite was only leached in the reducible and residual extraction steps. Some mercury associated with goethite was extracted in the ion exchangeable step, whereas mercury associated with hematite was extracted almost entirely in the residual step. Calcium in calcite and mercury associated with calcite were primarily removed in the acidsoluble extraction step. Titanium in titanium dioxide and mercury adsorbed onto titanium dioxide were extracted almost entirely in the residual step. 42 refs., 13 figs., 2 tabs.

  20. Rate of mercury loss from contaminated estuarine sediments

    USGS Publications Warehouse

    Bothner, Michael H.; Jahnke, R.A.; Peterson, M.L.; Carpenter, R.

    1980-01-01

    The concentration of mercury in contaminated estuarine sediments of Bellingham Bay, Washington was found to decrease with a half-time of about 1.3 yr after the primary anthropogenic source of mercury was removed. In situ measurements of the mercury flux from sediments, in both dissolved and volatile forms, could not account for this decrease. This result suggests that the removal of mercury is associated with sediment particles transported out of the study area. This decrease was modeled using a steady-state mixing model. Mercury concentrations in anoxic interstitial waters reached 3.5 ??g/l, 126 times higher than observed in the overlying seawater. Mercury fluxes from these sediments ranged from 1.2 to 2.8 ?? 10-5 ng/cm2/sec, all in a soluble form. In general, higher Hg fluxes were associated with low oxygen or reducing conditions in the overlying seawater. In contrast, no flux was measurable from oxidizing interstitial water having mercury concentrations of 0.01-0.06 ??/l. ?? 1980.

  1. Mercury binding sites in thiol-functionalized mesostructured silica.

    PubMed

    Billinge, Simon J L; McKimmy, Emily J; Shatnawi, Mouath; Kim, HyunJeong; Petkov, Valeri; Wermeille, Didier; Pinnavaia, Thomas J

    2005-06-15

    Thiol-functionalized mesostructured silica with anhydrous compositions of (SiO(2))(1)(-)(x)()(LSiO(1.5))(x)(), where L is a mercaptopropyl group and x is the fraction of functionalized framework silicon centers, are effective trapping agents for the removal of mercuric(II) ions from water. In the present work, we investigate the mercury-binding mechanism for representative thiol-functionalized mesostructures by atomic pair distribution function (PDF) analysis of synchrotron X-ray powder diffraction data and by Raman spectroscopy. The mesostructures with wormhole framework structures and compositions corresponding to x = 0.30 and 0.50 were prepared by direct assembly methods in the presence of a structure-directing amine porogen. PDF analyses of five mercury-loaded compositions with Hg/S ratios of 0.50-1.30 provided evidence for the bridging of thiolate sulfur atoms to two metal ion centers and the formation of chain structures on the pore surfaces. We find no evidence for Hg-O bonds and can rule out oxygen coordination of the mercury at greater than the 10% level. The relative intensities of the PDF peaks corresponding to Hg-S and Hg-Hg atomic pairs indicate that the mercury centers cluster on the functionalized surfaces by virtue of thiolate bridging, regardless of the overall mercury loading. However, the Raman results indicate that the complexation of mercury centers by thiolate depends on the mercury loading. At low mercury loadings (Hg/S < or = 0.5), the dominant species is an electrically neutral complex in which mercury most likely is tetrahedrally coordinated to bridging thiolate ligands, as in Hg(SBu(t))(2). At higher loadings (Hg/S 1.0-1.3), mercury complex cations predominate, as evidenced by the presence of charge-balancing anions (nitrate) on the surface. This cationic form of bound mercury is assigned a linear coordination to two bridging thiolate ligands. PMID:15941284

  2. Advanced Utility Mercury-Sorbent Field-Testing Program

    SciTech Connect

    Ronald Landreth

    2007-12-31

    This report summarizes the work conducted from September 1, 2003 through December 31, 2007 on the project entitled Advanced Utility Mercury-Sorbent Field-Testing Program. The project covers the testing at the Detroit Edison St. Clair Plant and the Duke Power Cliffside and Buck Stations. The St. Clair Plant used a blend of subbituminous and bituminous coal and controlled the particulate emissions by means of a cold-side ESP. The Duke Power Stations used bituminous coals and controlled their particulate emissions by means of hot-side ESPs. The testing at the Detroit Edison St. Clair Plant demonstrated that mercury sorbents could be used to achieve high mercury removal rates with low injection rates at facilities that burn subbituminous coal. A mercury removal rate of 94% was achieved at an injection rate of 3 lb/MMacf over the thirty day long-term test. Prior to this test, it was believed that the mercury in flue gas of this type would be the most difficult to capture. This is not the case. The testing at the two Duke Power Stations proved that carbon- based mercury sorbents can be used to control the mercury emissions from boilers with hot-side ESPs. It was known that plain PACs did not have any mercury capacity at elevated temperatures but that brominated B-PAC did. The mercury removal rate varies with the operation but it appears that mercury removal rates equal to or greater than 50% are achievable in facilities equipped with hot-side ESPs. As part of the program, both sorbent injection equipment and sorbent production equipment was acquired and operated. This equipment performed very well during this program. In addition, mercury instruments were acquired for this program. These instruments worked well in the flue gas at the St. Clair Plant but not as well in the flue gas at the Duke Power Stations. It is believed that the difference in the amount of oxidized mercury, more at Duke Power, was the difference in instrument performance. Much of the equipment was

  3. SO{sub 3} effect on mercury control

    SciTech Connect

    Jarvis, J.; Meserole, F.

    2008-01-15

    Utilities are counting on their flue gas desulfurization (FGD) scrubbers and selective catalytic reduction (SCR) systems to control mercury as well as pollutants such as SO{sub 2} and NOx. As more stringent emission limits are phased in, utilities will likely need supplemental measures such as activated carbon injection (ACI) to further reduce emissions. However, SO{sub 3} could foul this strategy and potentially jeopardize the ability of some coal-fired power plants to meet future mercury emission limits. A growing consensus exists among emissions control engineers and researchers that the presence of SO{sub 3} in the flue gas from coal-fired boilers reduces the capacity of fly ash and/or activated carbon to adsorb gaseous mercury species. The impact of SO{sub 3}, which is actually a combination of SO{sub 3} and H{sub 2}SO{sub 4} vapor, has been investigated on a fundamental level using approaches such as fixed-bed reactors and activated carbons. Pilot testing has provided mercury removal efficiency data on actual flue gas over a wide range of SO{sub 3} concentrations. If SO{sub 3} threatens the feasibility of low capital-cost approaches involving activated carbon, utilities will be forced to explore other more costly options. One example is the use of mercury catalytic oxidation to boost mercury removal efficiencies in wet scrubbers. However, catalytic oxidation of mercury using SCR catalysts may have unintended consequences. A better alternative may be to remove the SO{sub 3} so it does not interfere with the removal of mercury via the fly ash and/or activated carbon for example using sodium sorbents. The article outlines research projects on alternatives. 4 figs.

  4. Electrolytic recovery of mercury enriched in isotopic abundance

    DOEpatents

    Grossman, Mark W.

    1991-01-01

    The present invention is directed to a method of electrolytically extracting liquid mercury from HgO or Hg.sub.2 Cl.sub.2. Additionally there are disclosed two related techniques associated with the present invention, namely (1) a technique for selectively removing product from different regions of a long photochemical reactor (photoreactor) and (2) a method of accurately measuring the total quantity of mercury formed as either HgO or Hg.sub.2 Cl.sub.2.

  5. Retention of elemental mercury in fly ashes in different atmospheres

    SciTech Connect

    M.A. Lopez-Anton; M. Diaz-Somoano; M.R. Martinez-Tarazona

    2007-01-15

    Mercury is an extremely volatile element, which is emitted from coal combustion to the environment mostly in the vapor phase. To avoid the environmental problems that the toxic species of this element may cause, control technologies for the removal of mercury are necessary. Recent research has shown that certain fly ash materials have an affinity for mercury. Moreover, it has been observed that fly ashes may catalyze the oxidation of elemental mercury and facilitate its capture. However, the exact nature of Hg-fly ash interactions is still unknown, and mercury oxidation through fly ash needs to be investigated more thoroughly. In this work, the influence of a gas atmosphere on the retention of elemental mercury on fly ashes of different characteristics was evaluated. The retention capacity was estimated comparatively in inert and two gas atmospheres containing species present in coal gasification and coal combustion. Fly ashes produced in two pulverized coal combustion (PCC) plants, produced from coals of different rank (CTA and CTSR), and a fly ash (CTP) produced in a fluidized bed combustion (FBC) plant were used as raw materials. The mercury retention capacity of these fly ashes was compared to the retention obtained in different activated carbons. Although the capture of mercury is very similar in the gasification atmosphere and N{sub 2}, it is much more efficient in a coal combustion retention, being greater in fly ashes from PCC than those from FBC plants. 22 refs., 6 figs., 3 tabs.

  6. Mixed Waste Focus Area mercury contamination product line: An integrated approach to mercury waste treatment and disposal

    SciTech Connect

    Hulet, G.A.; Conley, T.B.; Morris, M.I.

    1998-07-01

    The US Department of Energy (DOE) Mixed Waste Focus Area (MWFA) is tasked with ensuring that solutions are available for the mixed waste treatment problems of the DOE complex. During the MWFA`s initial technical baseline development process, three of the top four technology deficiencies identified were related to the need for amalgamation, stabilization, and separation/removal technologies for the treatment of mercury and mercury-contaminated mixed waste. The focus area grouped mercury-waste-treatment activities into the mercury contamination product line under which development, demonstration, and deployment efforts are coordinated to provide tested technologies to meet the site needs. The Mercury Working Group (HgWG), a selected group of representatives from DOE sites with significant mercury waste inventories, is assisting the MWFA in soliciting, identifying, initiating, and managing efforts to address these areas. Based on the scope and magnitude of the mercury mixed waste problem, as defined by HgWG, solicitations and contract awards have been made to the private sector to demonstrate amalgamation and stabilization processes using actual mixed wastes. Development efforts are currently being funded under the product line that will address DOE`s needs for separation/removal processes. This paper discusses the technology selection process, development activities, and the accomplishments of the MWFA to date through these various activities.

  7. Conceptual studies for a mercury target circuit

    SciTech Connect

    Sigg, B.

    1996-06-01

    For the now favored target design of the European Spallation Source project, i.e. the version using mercury as target material, a basic concept of the primary system has been worked out. It does not include a detailed design of the various components of the target circuit, but tries to outline a feasible solution for the system. Besides the removal of the thermal power of about 3MW produced in the target by the proton beam, the primary system has to satisfy a number of other requirements related to processing, safety, and operation. The basic proposal uses an electromagnetic pump and a mercury-water intermediate heat excanger, but other alternatives are also being discussed. Basic safety requirements, i.e. protection against radiation and toxic mercury vapours, are satisfied by a design using an air-tight primary system containment, double-walled tubes in the intermediate heat exchanger, a fail-safe system for decay heat removal, and a remote handling facility for the active part of the system. Much engineering work has still to be done, because many details of the design of the mercury and gas processing systems remain to be clarified, the thermal-hydraulic components need further optimisation, the system for control and instrumentation is only known in outline and a through safety analysis will be required.

  8. Evaluation of Sorbent Injection for Mercury Control

    SciTech Connect

    Sharon Sjostrom

    2008-06-30

    ADA-ES, Inc., with support from DOE/NETL, EPRI, and industry partners, studied mercury control options at six coal-fired power plants. The overall objective of the this test program was to evaluate the capabilities of activated carbon injection at six plants: Sunflower Electric's Holcomb Station Unit 1, AmerenUE's Meramec Station Unit 2, Missouri Basin Power Project's Laramie River Station Unit 3, Detroit Edison's Monroe Power Plant Unit 4, American Electric Power's Conesville Station Unit 6, and Labadie Power Plant Unit 2. These plants have configurations that together represent 78% of the existing coal-fired generation plants. The financial goals for the program established by DOE/NETL were to reduce the uncontrolled mercury emissions by 50 to 70% at a cost 25 to 50% lower than the target established by DOE of $60,000 per pound of mercury removed. Results from testing at Holcomb, Laramie, Meramec, Labadie, and Monroe indicate the DOE goal was successfully achieved. However, further improvements for plants with conditions similar to Conesville are recommended that would improve both mercury removal performance and economics.

  9. Modeling Mercury in Proteins.

    PubMed

    Parks, J M; Smith, J C

    2016-01-01

    Mercury (Hg) is a naturally occurring element that is released into the biosphere both by natural processes and anthropogenic activities. Although its reduced, elemental form Hg(0) is relatively nontoxic, other forms such as Hg(2+) and, in particular, its methylated form, methylmercury, are toxic, with deleterious effects on both ecosystems and humans. Microorganisms play important roles in the transformation of mercury in the environment. Inorganic Hg(2+) can be methylated by certain bacteria and archaea to form methylmercury. Conversely, bacteria also demethylate methylmercury and reduce Hg(2+) to relatively inert Hg(0). Transformations and toxicity occur as a result of mercury interacting with various proteins. Clearly, then, understanding the toxic effects of mercury and its cycling in the environment requires characterization of these interactions. Computational approaches are ideally suited to studies of mercury in proteins because they can provide a detailed molecular picture and circumvent issues associated with toxicity. Here, we describe computational methods for investigating and characterizing how mercury binds to proteins, how inter- and intraprotein transfer of mercury is orchestrated in biological systems, and how chemical reactions in proteins transform the metal. We describe quantum chemical analyses of aqueous Hg(II), which reveal critical factors that determine ligand-binding propensities. We then provide a perspective on how we used chemical reasoning to discover how microorganisms methylate mercury. We also highlight our combined computational and experimental studies of the proteins and enzymes of the mer operon, a suite of genes that confer mercury resistance in many bacteria. Lastly, we place work on mercury in proteins in the context of what is needed for a comprehensive multiscale model of environmental mercury cycling. PMID:27497164

  10. Prolonged retention of methyl mercury by mallard drakes

    USGS Publications Warehouse

    Stickel, L.F.; Stickel, W.H.; McLane, M.A.R.; Bruns, M.

    1977-01-01

    Mallard drakes accumulated mercury rapidly from dietary dosage of methylmercury dicyandiamide and eliminated it slowly, retaining approximately one half at the end of 84 days; no measurable loss occurred between the end of the 7th and 56th days, but loss resumed concurrently with new feather growth, and continued through the 112th day, the close of the study.

  11. MODIFIED VALVE SEAT FOR THE STATIC MERCURY DROP ELECTRODE

    EPA Science Inventory

    A modification in the design of the valve seat of the static mercury drop electrode is presented. The creation of a 'four-point' seal within the modified valve seat prevents the capillary 'O' ring seal from becoming flattened and distorted. The design has eliminated air leakage i...

  12. Mercury transformation and speciation in flue gases from anthropogenic emission sources: a critical review

    NASA Astrophysics Data System (ADS)

    Zhang, Lei; Wang, Shuxiao; Wu, Qingru; Wang, Fengyang; Lin, Che-Jen; Zhang, Leiming; Hui, Mulin; Yang, Mei; Su, Haitao; Hao, Jiming

    2016-02-01

    Mercury transformation mechanisms and speciation profiles are reviewed for mercury formed in and released from flue gases of coal-fired boilers, non-ferrous metal smelters, cement plants, iron and steel plants, waste incinerators, biomass burning and so on. Mercury in coal, ores, and other raw materials is released to flue gases in the form of Hg0 during combustion or smelting in boilers, kilns or furnaces. Decreasing temperature from over 800 °C to below 300 °C in flue gases leaving boilers, kilns or furnaces promotes homogeneous and heterogeneous oxidation of Hg0 to gaseous divalent mercury (Hg2+), with a portion of Hg2+ adsorbed onto fly ash to form particulate-bound mercury (Hgp). Halogen is the primary oxidizer for Hg0 in flue gases, and active components (e.g., TiO2, Fe2O3, etc.) on fly ash promote heterogeneous oxidation and adsorption processes. In addition to mercury removal, mercury transformation also occurs when passing through air pollution control devices (APCDs), affecting the mercury speciation in flue gases. In coal-fired power plants, selective catalytic reduction (SCR) system promotes mercury oxidation by 34-85 %, electrostatic precipitator (ESP) and fabric filter (FF) remove over 99 % of Hgp, and wet flue gas desulfurization system (WFGD) captures 60-95 % of Hg2+. In non-ferrous metal smelters, most Hg0 is converted to Hg2+ and removed in acid plants (APs). For cement clinker production, mercury cycling and operational conditions promote heterogeneous mercury oxidation and adsorption. The mercury speciation profiles in flue gases emitted to the atmosphere are determined by transformation mechanisms and mercury removal efficiencies by various APCDs. For all the sectors reviewed in this study, Hgp accounts for less than 5 % in flue gases. In China, mercury emission has a higher Hg0 fraction (66-82 % of total mercury) in flue gases from coal combustion, in contrast to a greater Hg2+ fraction (29-90 %) from non-ferrous metal smelting, cement and

  13. Atmospheric Mercury Transfer to Peat Bogs Dominated by Gaseous Elemental Mercury Dry Deposition.

    PubMed

    Enrico, Maxime; Roux, Gaël Le; Marusczak, Nicolas; Heimbürger, Lars-Eric; Claustres, Adrien; Fu, Xuewu; Sun, Ruoyu; Sonke, Jeroen E

    2016-03-01

    Gaseous elemental mercury (GEM) is the dominant form of mercury in the atmosphere. Its conversion into oxidized gaseous and particulate forms is thought to drive atmospheric mercury wet deposition to terrestrial and aquatic ecosystems, where it can be subsequently transformed into toxic methylmercury. The contribution of mercury dry deposition is however largely unconstrained. Here we examine mercury mass balance and mercury stable isotope composition in a peat bog ecosystem. We find that isotope signatures of living sphagnum moss (Δ(199)Hg = -0.11 ± 0.09‰, Δ(200)Hg = 0.03 ± 0.02‰, 1σ) and recently accumulated peat (Δ(199)Hg = -0.22 ± 0.06‰, Δ(200)Hg = 0.00 ± 0.04‰, 1σ) are characteristic of GEM (Δ(199)Hg = -0.17 ± 0.07‰, Δ(200)Hg = -0.05 ± 0.02‰, 1σ), and differs from wet deposition (Δ(199)Hg = 0.73 ± 0.15‰, Δ(200)Hg = 0.21 ± 0.04‰, 1σ). Sphagnum covered during three years by transparent and opaque surfaces, which eliminate wet deposition, continue to accumulate Hg. Sphagnum Hg isotope signatures indicate accumulation to take place by GEM dry deposition, and indicate little photochemical re-emission. We estimate that atmospheric mercury deposition to the peat bog surface is dominated by GEM dry deposition (79%) rather than wet deposition (21%). Consequently, peat deposits are potential records of past atmospheric GEM concentrations and isotopic composition. PMID:26849121

  14. Controlling mercury emissions from coal-fired power plants

    SciTech Connect

    Chang, R.

    2009-07-15

    Increasingly stringent US federal and state limits on mercury emissions form coal-fired power plants demand optimal mercury control technologies. This article summarises the successful removal of mercury emissions achieved with activated carbon injection and boiler bromide addition, technologies nearing commercial readiness, as well as several novel control concepts currently under development. It also discusses some of the issues standing in the way of confident performance and cost predictions. In testing conducted on western coal-fired units with fabric filters or TOXECON to date, ACI has generally achieved mercury removal rates > 90%. At units with ESPs, similar performance requires brominated ACI. Alternatively, units firing western coals can use boiler bromide addition to increase flue gas mercury oxidation and downstream capture in a wet scrubber, or to enhance mercury removal by ACI. At eastern bituminous fired units with ESPs, ACI is not as effective, largely due to SO{sub 3} resulting from the high sulfur content of the coal or the use of SO{sub 3} flue gas conditioning to improve ESP performance. 7 refs., 3 figs.

  15. Single elimination competition

    NASA Astrophysics Data System (ADS)

    Fink, T. M. A.; Coe, J. B.; Ahnert, S. E.

    2008-09-01

    We study a simple model of competition in which each player has a fixed strength: randomly selected pairs of players compete, the stronger one wins and the loser is eliminated. We show that the best indicator of future success is not the number of wins but a player's wealth: the accumulated wealth of all defeated players. We calculate the distributions of strength and wealth for two versions of the problem: in the first, the loser is replaced; in the second, the loser is not. The probability of attaining a given wealth is shown to be path-independent. We illustrate our model with the popular game of conkers and discuss an extension to round-robin sports competition.

  16. Tissue content of mercury in rats given methylmercuric chloride orally: influence of intestinal flora

    SciTech Connect

    Rowland, I.R.; Davies, M.J.; Evans, J.G.

    1980-05-01

    The effect of intestinal flora on the absorption and disposition of mercury in tissues was investigated using conventional rats, and rats treated with antibiotics to eliminate their gut flora. Antibiotic-treated rats given (/sup 203/Hg) -labeled methylmercuric chloride orally had significantly more mercury in their tissues, especially in kidney, brain, lung, blood, and skeletal muscle, and also excreted less mercury in the feces than conventional rats. Furthermore, in the kidneys of the antibiotic-treated rats, the proportion of mercury present as organic mercury was greater than in the kidneys of the conventional rats. The results support the hypothesis that the metabolism of methylmercuric chloride by the gut flora reduces the tissue content of mercury. When rats were administered 10 mg methylmercuric chloride/Kg.day for 6 days, four or five of those given antibiotics developed neurological symptoms of toxicity, whereas only one of five conventional rats given methylmercuric chloride was affected.

  17. Elimination of frequency noise from groundwater measurements

    SciTech Connect

    Chien, Y.M.; Bryce, R.W.; Strait, S.R.; Yeatman, R.A.

    1986-04-01

    Groundwater response to atmospheric fluctuation can be effectively removed from downhole-pressure records using the systematic approach. The technique is not as successful for removal of earth tides, due to a probable discrepancy between the actual earth tide and the theoretical earth tide. The advantage of the systematic technique is that a causative relationship is established for each component of the pressure response removed. This concept of data reduction is easily understood and well accepted. The disadvantage is that a record of the stress causing the pressure fluctuation must be obtained. This may be done by monitoring or synthesizing the stress. Frequency analysis offers a simpler way to eliminate the undesirable hydrologic fluctuations from the downhole pressure. Frequency analysis may prove to be impractical if the fluctuations being removed have broadband characteristics. A combination of the two techniques, such as eliminating the atmospheric effect with the systematic method and the earth-tide fluctuations with the frequency method, is the most effective and efficient approach.

  18. Mercury in the environment

    SciTech Connect

    Idaho National Laboratory - Mike Abbott

    2008-08-06

    Abbott works for Idaho National Laboratory as an environmental scientist. Using state-of-thescienceequipment, he continuously samples the air, looking for mercury. In turn, he'll analyzethis long-term data and try to figure out the mercury's point of or

  19. Mercury and Pregnancy

    MedlinePlus

    ... made when mercury in the air gets into water. The mercury in the air comes from natural sources (such as volcanoes) and man-made sources (such as burning coal and other pollution). You can get methylmercury in your body by ...

  20. Mercury in the environment

    ScienceCinema

    Idaho National Laboratory - Mike Abbott

    2010-01-08

    Abbott works for Idaho National Laboratory as an environmental scientist. Using state-of-thescienceequipment, he continuously samples the air, looking for mercury. In turn, he'll analyzethis long-term data and try to figure out the mercury's point of or

  1. MESSENGER: Exploring Mercury's Magnetosphere

    NASA Technical Reports Server (NTRS)

    Slavin, James A.

    2008-01-01

    The MESSENGER mission to Mercury offers our first opportunity to explore this planet's miniature magnetosphere since Mariner 10's brief fly-bys in 1974-5. Mercury's magnetosphere is unique in many respects. The magnetosphere of Mercury is the smallest in the solar system with its magnetic field typically standing off the solar wind only - 1000 to 2000 km above the surface. For this reason there are no closed dri-fi paths for energetic particles and, hence, no radiation belts; the characteristic time scales for wave propagation and convective transport are short possibly coupling kinetic and fluid modes; magnetic reconnection at the dayside magnetopause may erode the subsolar magnetosphere allowing solar wind ions to directly impact the dayside regolith; inductive currents in Mercury's interior should act to modify the solar In addition, Mercury's magnetosphere is the only one with its defining magnetic flux tubes rooted in a planetary regolith as opposed to an atmosphere with a conductive ionosphere. This lack of an ionosphere is thought to be the underlying reason for the brevity of the very intense, but short lived, approx. 1-2 min, substorm-like energetic particle events observed by Mariner 10 in Mercury's magnetic tail. In this seminar, we review what we think we know about Mercury's magnetosphere and describe the MESSENGER science team's strategy for obtaining answers to the outstanding science questions surrounding the interaction of the solar wind with Mercury and its small, but dynamic magnetosphere.

  2. Blood Mercury Level

    EPA Science Inventory

    This indicator describes the presence of mercury in the blood of segments of the U.S. population from 1999 to 2008. Mercury can cause developmental and neurological problems, especially in children. This indicator shows how exposure to this environmental contaminant has change...

  3. MERCURY RESEARCH STRATEGY

    EPA Science Inventory

    The U.S. Environmental Protection Agency's (EPA's) Office of Research and Development (ORD) is pleased to announce the availability of its Mercury Research Strategy. This strategy guides ORD's mercury research program and covers the FY2001 2005 time frame. ORD will use it to ...

  4. Mercury On Deck

    NASA Technical Reports Server (NTRS)

    1963-01-01

    The crew of the U.S.S. Kearsarge spell out the words 'Mercury 9' on the ship's flight deck while on the way to the recovery area where astronaut Gordon Cooper is expected to splash down in his 'Faith 7' Mercury space capsule.

  5. Atmospheric Deposition of Mercury

    EPA Science Inventory

    With the advent of the industrial era, the amount of mercury entering the global environment increased dramatically. Releases of mercury in its elemental form from gold mines and chlor-alkali plants, as sulfides such as mercaptans and agricultural chemicals, and as volatile emiss...

  6. MODELING THE IMPACT OF ELEVATED MERCURY IN DEFENSE WASTE PROCESSING FACILITY MELTER FEED ON THE MELTER OFF-GAS SYSTEM - PRELIMINARY REPORT

    SciTech Connect

    Zamecnik, J.; Choi, A.

    2009-03-25

    The Defense Waste Processing Facility (DWPF) is currently evaluating an alternative Chemical Process Cell (CPC) flowsheet to increase throughput. It includes removal of the steam-stripping step, which would significantly reduce the CPC processing time and lessen the sampling needs. However, its downside would be to send 100% of the mercury that come in with the sludge straight to the melter. For example, the new mercury content in the Sludge Batch 5 (SB5) melter feed is projected to be 25 times higher than that in the SB4 with nominal steam stripping of mercury. This task was initiated to study the impact of the worst-case scenario of zero-mercury-removal in the CPC on the DWPF melter off-gas system. It is stressed that this study is intended to be scoping in nature, so the results presented in this report are preliminary. In order to study the impact of elevated mercury levels in the feed, it is necessary to be able to predict how mercury would speciate in the melter exhaust under varying melter operating conditions. A homogeneous gas-phase oxidation model of mercury by chloride was developed to do just that. The model contains two critical parameters pertaining to the partitioning of chloride among HCl, Cl, Cl{sub 2}, and chloride salts in the melter vapor space. The values for these parameters were determined at two different melter vapor space temperatures by matching the calculated molar ratio of HgCl (or Hg{sub 2}Cl{sub 2}) to HgCl{sub 2} with those measured during the Experimental-Scale Ceramic Melter (ESCM) tests run at the Pacific Northwest National Laboratory (PNNL). The calibrated model was then applied to the SB5 simulant used in the earlier flowsheet study with an assumed mercury stripping efficiency of zero; the molar ratio of Cl-to-Hg in the resulting melter feed was only 0.4, compared to 12 for the ESCM feeds. The results of the model run at the indicated melter vapor space temperature of 650 C (TI4085D) showed that due to excessive shortage of

  7. MODELING THE IMPACT OF ELEVATED MERCURY IN DEFENSE WASTE PROCESSING FACILITY MELTER FEED ON THE MELTER OFF-GAS SYSTEM-PRELIMINARY REPORT

    SciTech Connect

    Zamecnik, J.; Choi, A.

    2010-08-18

    The Defense Waste Processing Facility (DWPF) is currently evaluating an alternative Chemical Process Cell (CPC) flowsheet to increase throughput. It includes removal of the steam-stripping step, which would significantly reduce the CPC processing time and lessen the sampling needs. However, its downside would be to send 100% of the mercury that comes in with the sludge straight to the melter. For example, the new mercury content in the Sludge Batch 5 (SB5) melter feed is projected to be 25 times higher than that in the SB4 with nominal steam stripping of mercury. This task was initiated to study the impact of the worst-case scenario of zero-mercury-removal in the CPC on the DWPF melter offgas system. It is stressed that this study is intended to be scoping in nature, so the results presented in this report are preliminary. In order to study the impact of elevated mercury levels in the feed, it is necessary to be able to predict how mercury would speciate in the melter exhaust under varying melter operating conditions. A homogeneous gas-phase oxidation model of mercury by chloride was developed to do just that. The model contains two critical parameters pertaining to the partitioning of chloride among HCl, Cl, Cl{sub 2}, and chloride salts in the melter vapor space. The values for these parameters were determined at two different melter vapor space temperatures by matching the calculated molar ratio of HgCl (or Hg{sub 2}Cl{sub 2}) to HgCl{sub 2} with those measured during the Experimental-Scale Ceramic Melter (ESCM) tests run at the Pacific Northwest National Laboratory (PNNL). The calibrated model was then applied to the SB5 simulant used in the earlier flowsheet study with an assumed mercury stripping efficiency of zero; the molar ratio of Cl-to-Hg in the resulting melter feed was only 0.4, compared to 12 for the ESCM feeds. The results of the model run at the indicated melter vapor space temperature of 650 C (TI4085D) showed that due to excessive shortage of

  8. Further Investigation of the Impact of Sulfur Oxides on Mercury Capture by Activated Carbon

    SciTech Connect

    Presto, A.A.; Granite, E.J.; Karash, A.

    2007-11-21

    To gain a more complete understanding of the impact of sulfur oxides on mercury capture by activated carbon, continuous mercury concentration measurements were made downstream of a packed sorbent bed. Previous research from this laboratory, which is presented in a companion study, indicated that the mercury capacity of activated carbon during a 6 h exposure to mercury-laden simulated flue gas was inversely proportional to the S6+ content of the carbon. The results presented here indicate that high S6+ content limits both the 6-h capacity of activated carbon and the initial mercury removal efficiency. The observed reduction in initial mercury removal efficiency verifies the assumption that the 6-h mercury capacity is indicative of in-flight mercury capture efficiency during activated carbon injection. The activated carbon sample with the highest sulfur content tested here captured a minimal amount of mercury; however, this sample oxidized ~30% of the incident Hg0 at 100% breakthrough. This finding suggests that there are multiple available sites for mercury interaction with the sorbent surface, and that capture and oxidation occur at different surface sites.

  9. MERCURY MULTI-YEAR PLAN

    EPA Science Inventory

    A 1997 EPA Mercury Study Report to Congress discussed the magnitude of mercury emissions in the United States, and concluded that a plausible link exists between human activities that release mercury from industrial and combustion sources in the United States and methyl mercury c...

  10. Nanofiber Filters Eliminate Contaminants

    NASA Technical Reports Server (NTRS)

    2009-01-01

    With support from Phase I and II SBIR funding from Johnson Space Center, Argonide Corporation of Sanford, Florida tested and developed its proprietary nanofiber water filter media. Capable of removing more than 99.99 percent of dangerous particles like bacteria, viruses, and parasites, the media was incorporated into the company's commercial NanoCeram water filter, an inductee into the Space Foundation's Space Technology Hall of Fame. In addition to its drinking water filters, Argonide now produces large-scale nanofiber filters used as part of the reverse osmosis process for industrial water purification.

  11. Evaluation of Sorbent Injection for Mercury Control

    SciTech Connect

    Sharon Sjostrom

    2006-04-30

    The power industry in the U.S. is faced with meeting new regulations to reduce the emissions of mercury compounds from coal-fired plants. These regulations are directed at the existing fleet of nearly 1,100 boilers. These plants are relatively old with an average age of over 40 years. Although most of these units are capable of operating for many additional years, there is a desire to minimize large capital expenditures because of the reduced (and unknown) remaining life of the plant to amortize the project. Injecting a sorbent such as powdered activated carbon into the flue gas represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. This is the final site report for tests conducted at DTE Energy's Monroe Power Plant, one of five sites evaluated in this DOE/NETL program. The overall objective of the test program was to evaluate the capabilities of activated carbon injection at five plants: Sunflower Electric's Holcomb Station Unit 1, AmerenUE's Meramec Station Unit 2, Missouri Basin Power Project's Laramie River Station Unit 3, Detroit Edison's Monroe Power Plant Unit 4, and AEP's Conesville Station Unit 6. These plants have configurations that together represent 78% of the existing coal-fired generation plants. The goals for the program established by DOE/NETL were to reduce the uncontrolled mercury emissions by 50 to 70% at a cost 25 to 50% lower than the target established by DOE of $60,000/lb mercury removed. The results from Monroe indicate that using DARCO{reg_sign} Hg would result in higher mercury removal (80%) at a sorbent cost of $18,000/lb mercury, or 70% lower than the benchmark. These results demonstrate that the goals established by DOE/NETL were exceeded during this test program. The increase in mercury removal over baseline conditions is defined for this program as a comparison in the outlet emissions measured using the Ontario Hydro method during the baseline and long-term test periods

  12. Task 2.8 -- Mercury speciation and capture in scrubber solutions. Semi-annual report, July 1--December 31, 1996

    SciTech Connect

    Ness, S.R.

    1997-08-01

    Investigations into mercury control across conventional scrubber systems have precipitated questions concerning (1) the initial speciation between oxidized and elemental forms of mercury in flue gas from coal-fired boilers and, subsequently, (2) the effects of scrubber slurry composition and pH on the mercury forms. Mercury capture in scrubber slurry is highly dependent on its form. Oxidized mercury is highly water-soluble and can be removed by scrubber slurry, whereas elemental mercury is not and passes through the scrubber to the stack. The objectives of this project are to determine whether scrubber solutions convert either form of mercury to another and whether mercury capture is affected by pH.

  13. EVALUATION OF THE IMPACT OF CHLORINE ON MERCURY OXIDATION IN A PILOT-SCALE COAL COMBUSTION--THE EFFECT OF COAL BLENDING

    EPA Science Inventory

    Coal-fired power plants are a major source of mercury (Hg) released into the environment and the utility industry is currently investigating options to reduce Hg emissions. The EPA Clean Air Mercury Rule (CAMR) depends heavily on the co-benefit of mercury removal by existing and ...

  14. Evaluation of a sequential extraction process used for determining mercury binding mechanisms to coal combustion byproducts.

    PubMed

    Noel, James D; Biswas, Pratim; Giammar, Daniel E

    2007-07-01

    Leaching of mercury from coal combustion byproducts is a concern because of the toxicity of mercury. Leachability of mercury can be assessed by using sequential extraction procedures. Sequential extraction procedures are commonly used to determine the speciation and mobility of trace metals in solid samples and are designed to differentiate among metals bound by different mechanisms and to different solid phases. This study evaluated the selectivity and effectiveness of a sequential extraction process used to determine mercury binding mechanisms to various materials. A six-step sequential extraction process was applied to laboratory-synthesized materials with known mercury concentrations and binding mechanisms. These materials were calcite, hematite, goethite, and titanium dioxide. Fly ash from a full-scale power plant was also investigated. The concentrations of mercury were measured using inductively coupled plasma (ICP) mass spectrometry, whereas the major elements were measured by ICP atomic emission spectrometry. The materials were characterized by X-ray powder diffraction and scanning electron microscopy with energy dispersive spectroscopy. The sequential extraction procedure provided information about the solid phases with which mercury was associated in the solid sample. The procedure effectively extracted mercury from the target phases. The procedure was generally selective in extracting mercury. However, some steps in the procedure extracted mercury from nontarget phases, and others resulted in mercury redistribution. Iron from hematite and goethite was only leached in the reducible and residual extraction steps. Some mercury associated with goethite was extracted in the ion exchangeable step, whereas mercury associated with hematite was extracted almost entirely in the residual step. Calcium in calcite and mercury associated with calcite were primarily removed in the acid-soluble extraction step. Titanium in titanium dioxide and mercury adsorbed onto

  15. The materials flow of mercury in the economies of the United States and the world

    USGS Publications Warehouse

    Sznopek, John L.; Goonan, Thomas G.

    2000-01-01

    Although natural sources of mercury exist in the environment, measured data and modeling results indicate that the amount of mercury released into the biosphere has increased since the beginning of the industrial age. Mercury is naturally distributed in the air, water, and soil in minute amounts, and can be mobile within and between these media. Because of these properties and the subsequent impacts on human health, mercury was selected for an initial materials flow study, focusing on the United States in 1990. This study was initiated to provide a current domestic and international analysis. As part of an increased emphasis on materials flow, this report researched changes and identified the associated trends in mercury flows; it also updates statistics through 1996. In addition to domestic flows, the report includes an international section, because all primary mercury-producing mines are currently foreign, 86 percent of the mercury cell sector of the worldwide chlor-alkali industry is outside the United States, there is a large international mercury trade (1,395 t 1 in 1996), and environmental regulations are not uniform or similarly enforced from country to country. Environmental concerns have brought about numerous regulations that have dramatically decreased both the use and the production of mercury since the late 1980?s. Our study indicates that this trend is likely to continue into the future, as the world eliminates the large mercury inventories that have been stockpiled to support prior industrial processes and products.

  16. Final report for the Central Mercury Treatment System in Building 9623 at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    SciTech Connect

    1997-02-01

    This document discusses the construction of the Central Mercury Treatment System (CMTS) in Building 9623 at the Y-12 Plant, the remediation activities involved, waste generated from the project, and the monitoring schedule of the CMTS. As part of the Reduction of Mercury in Plant Effluent Program, the project treats groundwater contaminated with mercury from Buildings 9201-4, 9201-5, and 9204-4 at the Y-12 Plant to meet National Pollutant Discharge Elimination System (NPDES) Permit limits for discharge to East Fork Poplar Creek. The CMTS, located in Building 9623, will treat water from the sumps of buildings in which mercury was used in operations and which have been shown to be significant contributors to the overall levels of mercury in plant effluents. This project was anticipated when the NPDES Permit was issued, and the contamination limits and frequency of monitoring for the system discharge are detailed in the permit as Outfall 551. This project was performed as an Incentive Task Order and included the advance procurement of the carbon columns, removal of existing equipment in Building 9623, and system installation and checkout. Construction activities for installing the system started in January 1996 after the area in Building 9623 had been cleared of existing, obsolete equipment. The CMTS became operational on November 26, 1996, well ahead of the permit start date of January 1, 1998. The early completion date allows Hg concentrations in EFPC to be evaluated to determine whether further actions are required to meet NPDES permit limits for reduced Hg loading to the creek.

  17. Anthropogenic mercury emission inventory with emission factors and total emission in Korea

    NASA Astrophysics Data System (ADS)

    Kim, Jeong-Hun; Park, Jung-Min; Lee, Sang-Bo; Pudasainee, Deepak; Seo, Yong-Chil

    2010-07-01

    Mercury emissions concentrations, emission factors, and the total national emission from major anthropogenic sources in Korea for the year 2007 were estimated. Uncontrolled and controlled mercury emission factors and the total emission from each source types are presented. The annual national mercury emission from major anthropogenic sources for the year 2007, on average was 12.8 ton which ranged from 6.5 to 20.2 ton. Averaged emissions of elemental, oxidized, and particulate mercury were estimated at 8.25 ton, 3.69 ton, and 0.87 ton, respectively. Due to the removal of a major portion of particulate and oxidized mercury species, elemental mercury was dominant in stack emission. About 54.8% of mercury emission was contributed by industrial sources, 45.0% by stationary combustion sources and 0.02% by mobile sources. Thermal power plants, oil refineries, cement kilns and incinerators (municipal, industrial, medical, sewage sludge) were the major mercury emitters, contributing about 26%, 25%, 21% and 20%, respectively to the total mercury emission. Other sources (crematory, pulp and paper manufacturing, nonferrous metals manufacturing, glass manufacturing) contributed about 8% of the total emission. Priority should be given in controlling mercury emissions from coal-fired power plants, oil refineries, cement kilns and waste incinerators. More measurements including natural and re-emission sources are to be carried out in the future in order to have a clear scenario of mercury emission from the country and to apply effective control measures.

  18. Biochemical Removal of HAP Precursors from Coal

    SciTech Connect

    Olson, Gregory J

    1997-05-12

    Column biooxidation tests with Kentucky coal confirmed results of earlier shake flask tests showing significant removal from the coal of arsenic, selenium, cobalt, manganese, nickel and cadmium. Rates of pyrite biooxidation in Kentucky coal were only slightly more than half the rates found previously for Indiana and Pittsburgh coals. Removal of pyrite from Pittsburgh coal by ferric ion oxidation slows markedly as ferrous ions accumulate in solution, requiring maintenance of high redox potentials in processes designed for removal of pyrite and hazardous air pollutant (HAP) precursors by circulation of ferric solutions through coal. The pyrite oxidation rates obtained in these tests were used by Unifield Engineering to support the conceptual designs for alternative pyrite and HAP precursor bioleaching processes for the phase 2 pilot plant. Thermophilic microorganisms were tested to determine if mercury could be mobilized from coal under elevated growth temperatures. There was no evidence for mercury removal from coal under these conditions. However, the activity of the organisms may have liberated mercury physically. It is also possible that the organisms dissolved mercury and it readsorbed to the clay preferentially. Both of these possibilities are undergoing further testing. The Idaho National Engineering and Environmental Laboratory's (INEEL) slurry column reactor was operated and several batches of feed coal, product coal, waste solids and leach solutions were submitted to LBL for HAP precursor analysis. Results to date indicate significant removal of mercury, arsenic and other HAP precursors in the combined physical-biological process.

  19. Mercury's Dynamic Magnetic Tail

    NASA Technical Reports Server (NTRS)

    Slavin, James A.

    2010-01-01

    The Mariner 10 and MESSENGER flybys of Mercury have revealed a magnetosphere that is likely the most responsive to upstream interplanetary conditions of any in the solar system. The source of the great dynamic variability observed during these brief passages is due to Mercury's proximity to the Sun and the inverse proportionality between reconnection rate and solar wind Alfven Mach number. However, this planet's lack of an ionosphere and its small physical dimensions also contribute to Mercury's very brief Dungey cycle, approx. 2 min, which governs the time scale for internal plasma circulation. Current observations and understanding of the structure and dynamics of Mercury's magnetotail are summarized and discussed. Special emphasis will be placed upon such questions as: 1) How much access does the solar wind have to this small magnetosphere as a function of upstream conditions? 2) What roles do heavy planetary ions play? 3) Do Earth-like substorms take place at Mercury? 4) How does Mercury's tail respond to extreme solar wind events such coronal mass ejections? Prospects for progress due to advances in the global magnetohydrodynamic and hybrid simulation modeling and the measurements to be taken by MESSENGER after it enters Mercury orbit on March 18, 2011 will be discussed.

  20. Mercury in the ecosystem

    SciTech Connect

    Mitra, S.

    1986-01-01

    This treatise on the environmental dispersion of mercury emphasizes the importance of ''mercury-consciousness'' in the present-day world, where rapidly expanding metallurgical, chemical, and other industrial developments are causing widespread contamination of the atmosphere, soil, and water by this metal and its toxic organic derivatives. Concepts concerning the mechanism of mercury dispersion and methyl-mercury formation in the physico-biological ecosystem are discussed in detail and a substantial body of data on the degree and nature of the mercury contamination of various plants, fish, and land animals by industrial and urban effluents is presented. Various analytical methods for the estimation of mercury in inorganic and organic samples are presented. These serve as a ready guide to the selection of the correct method for analyzing environmental samples. This book is reference work in mercury-related studies. It is written to influence industrial policies of governments in their formulation of control measures to avoid the recurrence of human tragedies such as the well-known Minamata case in Japan, and the lesser known cases in Iraq, Pakistan, and Guatamala.

  1. Mercury Metadata Toolset

    Energy Science and Technology Software Center (ESTSC)

    2009-09-08

    Mercury is a federated metadata harvesting, search and retrieval tool based on both open source software and software developed at Oak Ridge National Laboratory. It was originally developed for NASA, and the Mercury development consortium now includes funding from NASA, USGS, and DOE. A major new version of Mercury (version 3.0) was developed during 2007 and released in early 2008. This Mercury 3.0 version provides orders of magnitude improvements in search speed, support for additionalmore » metadata formats, integration with Google Maps for spatial queries, facetted type search, support for RSS delivery of search results, and ready customization to meet the needs of the multiple projects which use Mercury. For the end users, Mercury provides a single portal to very quickly search for data and information contained in disparate data management systems. It collects metadata and key data from contributing project servers distributed around the world and builds a centralized index. The Mercury search interfaces then allow the users to perform simple, fielded, spatial, and temporal searches across these metadata sources. This centralized repository of metadata with distributed data sources provides extremely fast search results to the user, while allowing data providers to advertise the availability of their data and maintain complete control and ownership of that data.« less

  2. Mercury Metadata Toolset

    SciTech Connect

    2009-09-08

    Mercury is a federated metadata harvesting, search and retrieval tool based on both open source software and software developed at Oak Ridge National Laboratory. It was originally developed for NASA, and the Mercury development consortium now includes funding from NASA, USGS, and DOE. A major new version of Mercury (version 3.0) was developed during 2007 and released in early 2008. This Mercury 3.0 version provides orders of magnitude improvements in search speed, support for additional metadata formats, integration with Google Maps for spatial queries, facetted type search, support for RSS delivery of search results, and ready customization to meet the needs of the multiple projects which use Mercury. For the end users, Mercury provides a single portal to very quickly search for data and information contained in disparate data management systems. It collects metadata and key data from contributing project servers distributed around the world and builds a centralized index. The Mercury search interfaces then allow the users to perform simple, fielded, spatial, and temporal searches across these metadata sources. This centralized repository of metadata with distributed data sources provides extremely fast search results to the user, while allowing data providers to advertise the availability of their data and maintain complete control and ownership of that data.

  3. Mercury Emission Control Technologies for PPL Montana-Colstrip Testing

    SciTech Connect

    John P. Kay; Michael L. Jones; Steven A. Benson

    2007-04-01

    The Energy & Environmental Research Center (EERC) was asked by PPL Montana LLC (PPL) to provide assistance and develop an approach to identify cost-effective options for mercury control at its coal-fired power plants. The work conducted focused on baseline mercury level and speciation measurement, short-term parametric testing, and week long testing of mercury control technology at Colstrip Unit 3. Three techniques and various combinations of these techniques were identified as viable options for mercury control. The options included oxidizing agents or sorbent enhancement additives (SEAs) such as chlorine-based SEA1 and an EERC proprietary SEA2 with and without activated carbon injection. Baseline mercury emissions from Colstrip Unit 3 are comparatively low relative to other Powder River Basin (PRB) coal-fired systems and were found to range from 5 to 6.5 g/Nm3 (2.9 to 3.8 lb/TBtu), with a rough value of approximately 80% being elemental upstream of the scrubber and higher than 95% being elemental at the outlet. Levels in the stack were also greater than 95% elemental. Baseline mercury removal across the scrubber is fairly variable but generally tends to be about 5% to 10%. Parametric results of carbon injection alone yielded minimal reduction in Hg emissions. SEA1 injection resulted in 20% additional reduction over baseline with the maximum rate of 400 ppm (3 gal/min). Week long testing was conducted with the combination of SEA2 and carbon, with injection rates of 75 ppm (10.3 lb/hr) and 1.5 lb/MMacf (40 lb/hr), respectively. Reduction was found to be an additional 30% and, overall during the testing period, was measured to be 38% across the scrubber. The novel additive injection method, known as novel SEA2, is several orders of magnitude safer and less expensive than current SEA2 injection methods. However, used in conjunction with this plant configuration, the technology did not demonstrate a significant level of mercury reduction. Near-future use of this

  4. USA supports measles elimination.

    PubMed

    1996-06-01

    The United States, through the United States Agency for International Development (USAID), has approved an $8 million grant in support of the Pan American Health Organization (PAHO) goal to eliminate measles in the Americas by the year 2000. From 1996 to 2001, the grant will complement regional efforts to stop the disease. Mrs. Hillary Clinton had pledged the support on World Health Day 1995. Although record low levels of measles cases were reported in 1995 for the region, the virus could be imported from elsewhere in the world. A major obstacle is the accumulation of susceptible preschool-aged children. As the proportion of susceptibles expands, the risk of a measles outbreak increases, if the virus is reintroduced. To prevent this, follow-up campaigns are being conducted throughout the region, focusing on all children aged 1-4 years, regardless of previous vaccination or disease history. PAHO recommends follow-up whenever the number of susceptible preschool children approaches the size of an average birth cohort. The interval between these campaigns and the specific age group targeted will depend on the vaccination coverage obtained through routine services since the last campaign. Follow-up campaigns were conducted in Cuba in 1993; in Belize, Brazil, Columbia, and Jamaica in 1995; and in Chile and the countries of Central America during April 1996. 19 million children were reached. Follow-up campaigns are planned for the remaining countries of the English-speaking Caribbean later in 1996. USAID played a key role in the successful completion of the 1994 poliomyelitis eradication initiative; the agency contributed approximately 60% of the external costs associated with the hemispheric campaign. PMID:12347182

  5. Global change and mercury

    USGS Publications Warehouse

    Krabbenhoft, David P.; Sunderland, Elsie M.

    2013-01-01

    More than 140 nations recently agreed to a legally binding treaty on reductions in human uses and releases of mercury that will be signed in October of this year. This follows the 2011 rule in the United States that for the first time regulates mercury emissions from electricity-generating utilities. Several decades of scientific research preceded these important regulations. However, the impacts of global change on environmental mercury concentrations and human exposures remain a major uncertainty affecting the potential effectiveness of regulatory activities.

  6. Missions to Mercury

    NASA Astrophysics Data System (ADS)

    Grard, Réjean; Laakso, Harry; Svedhem, Håkan

    2002-10-01

    Mercury is a poorly known planet. It is difficult to observe from Earth and to explore with spacecraft, due to its proximity to the Sun. Only the NASA probe Mariner 10 caught a few glimpses of Mercury during three flybys, more than 27 years ago. Still, this planet is an interesting and important object because it belongs, like our own Earth, to the family of the terrestrial planets. After reviewing what we know about Mercury and recapitulating the major findings of Mariner 10, we present the two missions, Messenger and BepiColombo, which will perform the first systematic exploration of this forgotten planet in 2009 and 2014, respectively.

  7. Measuring lead, mercury, and uranium by in vivo X-ray fluorescence

    NASA Astrophysics Data System (ADS)

    O'Meara, Joanne Michelle

    X-ray fluorescence (XRF) has been demonstrated to be a useful technique for measuring trace quantities of heavy metals in various tissues within the body. This thesis investigates a means of improving the measurement of lead in bone, as well as increasing the existing sensitivity of measuring kidney mercury content. The XRF measurement of uranium is also explored. This work assesses the feasibility of a normalisation method for the 57Co/90° system, in relating detected signal to the lead content of the sample. The feasibility of normalisation has been shown, which reduces subject dose and improves system transportability, as well as removes subjectivity, by eliminating the need for acquiring planar x-ray images of the measurement site. In the measurement of renal mercury concentrations, a gain in sensitivity increasing the x-ray tube operating voltage of the current system is investigated. It found that 250 kV, rather than 175 kV, and a titanium rather than uranium filter, results in a 2.5 +/- 0.2 times gain in sensitivity. This potential improvement could have profound clinical implications for the accuracy of occupational monitoring, and for assessing whether there is a quantitative relationship between biological fluid levels and mercury content in this critical organ. The XRF measurement of bone uranium content is also explored. Both source-excited and polarised systems have been developed, however, the sensitivity is currently beyond that which is useful for occupational monitoring of exposure to this toxin. The particular case of measuring uranium in survivors of "Friendly Fire" incidents (from Operation Desert Storm) is investigated, and the first detectable quantity of uranium has been observed in a member of this cohort, with the XRF system designed and built during the course of this work.

  8. Recovery from Mercury Contamination in the Second Songhua River, China

    PubMed Central

    Zhang, Z. S.; Sun, X. J.; Wang, Q. C.; Zheng, D. M.; Zheng, N.

    2009-01-01

    Mercury pollution in the Second Songhua River (SSR) was serious in the last century due to effluent from a chemical corporation. Effects of riverine self-purification on mercury removal were studied by comparing monitoring data of mercury concentrations varieties in water, sediment, and fish in the past, about 30 years. The present work suggested that a river of such a size like the SSR possessed the potential ability to recover from mercury pollution under the condition that mercury sources were cut off, though it needs a very long time, which might be several decades or even a century of years. During the 30 years with no effluent containing mercury input, total mercury (T-Hg) of water and sediment in some typical segments, mostly near the past effluent outlet, had decreased radically but still higher than the background values, though the decrease amplitudes were over 90% compared with that in 1975. T-Hg had decreased by more than 90% in most fishes, but some were still not suitable for consumption. Methylmercury concentrations (MeHg) of water, sediment, and fish were higher or close to the background levels in 2004. In the coming decades, the purification processes in the SSR would be steady and slow for a long period. PMID:20835296

  9. Remediation Technologies Eliminate Contaminants

    NASA Technical Reports Server (NTRS)

    2012-01-01

    groundwater tainted by chlorinated solvents once used to clean rocket engine components. The award-winning innovation (Spinoff 2010) is now NASA s most licensed technology to date. PCBs in paint presented a new challenge. Removing the launch stand for recycling proved a difficult operation; the toxic paint had to be fully stripped from the steel structure, a lengthy and costly process that required the stripped paint to be treated before disposal. Noting the lack of efficient, environmentally friendly options for dealing with PCBs, Quinn and her colleagues developed the Activated Metal Treatment System (AMTS). AMTS is a paste consisting of a solvent solution containing microscale particles of activated zero-valent metal. When applied to a painted surface, the paste extracts and degrades the PCBs into benign byproducts while leaving the paint on the structure. This provides a superior alternative to other methods for PCB remediation, such as stripping the paint or incinerating the structure, which prevents reuse and can release volatized PCBs into the air. Since its development, AMTS has proven to be a valuable solution for removing PCBs from paint, caulking, and various insulation and filler materials in older buildings, naval ships, and former munitions facilities where the presence of PCBs interferes with methods for removing trace explosive materials. Miles of potentially toxic caulking join sections of runways at airports. Any of these materials installed before 1979 potentially contain PCBs, Quinn says. "This is not just a NASA problem," she says. "It s a global problem."

  10. Mercury free microscopy: an opportunity for core facility directors.

    PubMed

    Baird, T Regan; Kaufman, Daniel; Brown, Claire M

    2014-07-01

    Mercury Free Microscopy (MFM) is a new movement that encourages microscope owners to choose modern mercury free light sources to replace more traditional mercury based arc lamps. Microscope performance is enhanced with new solid state technologies because they offer a more stable light intensity output and have a more uniform light output across the visible spectrum. Solid state sources not only eliminate mercury but also eliminate the cost of consumable bulbs (lifetime ∼200 hours), use less energy, reduce the instrument down time when bulbs fail and reduce the staff time required to replace and align bulbs. With lifetimes on the order of tens of thousands of hours, solid state replacements can pay for themselves over their lifetime with the omission of consumable, staff (no need to replace and align bulbs) and energy costs. Solid state sources are also sustainable and comply with institutional and government body mandates to reduce energy consumption, carbon footprints and hazardous waste. MFM can be used as a mechanism to access institutional financial resources for sustainable technology through a variety of stakeholders to defray the cost to microscope owners for the initial purchase of solid state sources or the replacement cost of mercury based sources. Core facility managers can take a lead in this area as "green" ambassadors for their institution by championing a local MFM program that will save their institution money and energy and eliminate mercury from the waste stream. Managers can leverage MFM to increase the visibility of their facility, their impact within the institution, and as a vital educational resource for scientific and administrative consultation. PMID:24982596

  11. Mercury Free Microscopy: An Opportunity for Core Facility Directors

    PubMed Central

    Baird, T. Regan; Kaufman, Daniel; Brown, Claire M.

    2014-01-01

    Mercury Free Microscopy (MFM) is a new movement that encourages microscope owners to choose modern mercury free light sources to replace more traditional mercury based arc lamps. Microscope performance is enhanced with new solid state technologies because they offer a more stable light intensity output and have a more uniform light output across the visible spectrum. Solid state sources not only eliminate mercury but also eliminate the cost of consumable bulbs (lifetime ∼200 hours), use less energy, reduce the instrument down time when bulbs fail and reduce the staff time required to replace and align bulbs. With lifetimes on the order of tens of thousands of hours, solid state replacements can pay for themselves over their lifetime with the omission of consumable, staff (no need to replace and align bulbs) and energy costs. Solid state sources are also sustainable and comply with institutional and government body mandates to reduce energy consumption, carbon footprints and hazardous waste. MFM can be used as a mechanism to access institutional financial resources for sustainable technology through a variety of stakeholders to defray the cost to microscope owners for the initial purchase of solid state sources or the replacement cost of mercury based sources. Core facility managers can take a lead in this area as “green” ambassadors for their institution by championing a local MFM program that will save their institution money and energy and eliminate mercury from the waste stream. Managers can leverage MFM to increase the visibility of their facility, their impact within the institution, and as a vital educational resource for scientific and administrative consultation. PMID:24982596

  12. EVALUATION OF MERCURY EMISSIONS FROM COAL-FIRED FACILITIES WITH SCR AND FGD SYSTEMS

    SciTech Connect

    J.A. Withum; S.C. Tseng; J.E. Locke

    2005-11-01

    CONSOL Energy Inc., Research & Development (CONSOL), with support from the U.S. Department of Energy, National Energy Technology Laboratory (DOE) and the Electric Power Research Institute (EPRI), is evaluating the effects of selective catalytic reduction (SCR) on mercury (Hg) capture in coal-fired plants equipped with an electrostatic precipitator (ESP)--wet flue gas desulfurization (FGD) combination or a spray dryer absorber--fabric filter (SDA-FF) combination. In this program CONSOL is determining mercury speciation and removal at 10 coal-fired facilities. The objectives are (1) to evaluate the effect of SCR on mercury capture in the ESP-FGD and SDA-FF combinations at coal-fired power plants, (2) evaluate the effect of catalyst degradation on mercury capture; (3) evaluate the effect of low load operation on mercury capture in an SCR-FGD system, and (4) collect data that could provide the basis for fundamental scientific insights into the nature of mercury chemistry in flue gas, the catalytic effect of SCR systems on mercury speciation and the efficacy of different FGD technologies for mercury capture. This document, the seventh in a series of topical reports, describes the results and analysis of mercury sampling performed on a 1,300 MW unit burning a bituminous coal containing three percent sulfur. The unit was equipped with an ESP and a limestone-based wet FGD to control particulate and SO2 emissions, respectively. At the time of sampling an SCR was not installed on this unit. Four sampling tests were performed in September 2003. Flue gas mercury speciation and concentrations were determined at the ESP outlet (FGD inlet), and at the stack (FGD outlet) using the Ontario Hydro method. Process stream samples for a mercury balance were collected to coincide with the flue gas measurements. The results show that the FGD inlet flue gas oxidized:elemental mercury ratio was roughly 2:1, with 66% oxidized mercury and 34% elemental mercury. Mercury removal, on a coal

  13. Investigation and Demonstration of Dry Carbon-Based Sorbent Injection for Mercury Control

    SciTech Connect

    Jim Butz; Terry Hunt

    2005-11-01

    Public Service Company of Colorado and ADA Technologies, Inc. have performed a study of the injection of activated carbon for the removal of vapor-phase mercury from coal-fired flue gas streams. The project was completed under contract to the US Department of Energy's National Energy Technology Laboratory, with contributions from EPRI and Public Service Company. The prime contractor for the project was Public Service Company, with ADA Technologies as the major subcontractor providing technical support to all aspects of the project. The research and development effort was conducted in two phases. In Phase I a pilot facility was fabricated and tests were performed using dry carbon-based sorbent injection for mercury control on a coal-fired flue gas slipstream extracted from an operating power plant. Phase II was designed to move carbon injection technology towards commercial application on coal-fired power plants by addressing key reliability and operability concerns. Phase II field work included further development work with the Phase I pilot and mercury measurements on several of PSCo's coal-fired generating units. In addition, tests were run on collected sorbent plus fly ash to evaluate the impact of the activated carbon sorbent on the disposal of fly ash. An economic analysis was performed where pilot plant test data was used to develop a model to predict estimated costs of mercury removal from plants burning western coals. Testing in the pilot plant was undertaken to quantify the effects of plant configuration, flue gas temperature, and activated carbon injection rate on mercury removal. All three variables were found to significantly impact the mercury removal efficiency in the pilot. The trends were clear: mercury removal rates increased with decreasing flue gas temperature and with increasing carbon injection rates. Mercury removal was much more efficient with reverse-gas and pulse-jet baghouse configurations than with an ESP as the particulate control device

  14. Recovery of mercury from mercury compounds via electrolytic methods

    DOEpatents

    Grossman, M.W.; George, W.A.

    1989-11-07

    A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg[sub 2]Cl[sub 2] employing as the electrolyte solution a mixture of HCl and H[sub 2]O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H[sub 2]O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds. 3 figs.

  15. Recovery of mercury from mercury compounds via electrolytic methods

    DOEpatents

    Grossman, Mark W.; George, William A.

    1989-01-01

    A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg.sub.2 Cl.sub.2 employing as the electrolyte solution a mixture of HCl and H.sub.2 O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H.sub.2 O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds.

  16. Recovery of mercury from mercury compounds via electrolytic methods

    DOEpatents

    Grossman, M.W.; George, W.A.

    1991-06-18

    A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg[sub 2]Cl[sub 2] employing as the electrolyte solution a mixture of HCl and H[sub 2]O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H[sub 2]O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds. 3 figures.

  17. Recovery of mercury from mercury compounds via electrolytic methods

    DOEpatents

    Grossman, Mark W.; George, William A.

    1991-01-01

    A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg.sub.2 Cl.sub.2 employing as the electrolyte solution a mixture of HCl and H.sub.2 O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H.sub.2 O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds.

  18. Recovery of mercury from mercury compounds via electrolytic methods

    DOEpatents

    Grossman, Mark W.; George, William A.

    1988-01-01

    A process for electrolytically recovering mercury from mercury compounds is provided. In one embodiment, Hg is recovered from Hg.sub.2 Cl.sub.2 employing as the electrolyte solution a mixture of HCl and H.sub.2 O. In another embodiment, Hg is electrolytically recovered from HgO wherein the electrolyte solution is comprised of glacial acetic acid and H.sub.2 O. Also provided is an apparatus for producing isotopically enriched mercury compounds in a reactor and then transporting the dissolved compounds into an electrolytic cell where mercury ions are electrolytically reduced and elemental mercury recovered from the mercury compounds.

  19. SiO2/TiO2 Composite for Removing Hg from Combustion Exhaust

    NASA Technical Reports Server (NTRS)

    Mazyck, David; Londeree, Danielle; Wu, Chang-Yu; Powers, Kevin; Pitoniak, Erik

    2008-01-01

    Pellets made of a high-surface-area composite of silica and titania have shown promise as means of removing elemental mercury from flue gases. With further technical development and commercialization, this material could become economically attractive as a more effective, less-expensive alternative to activated carbons for removing mercury from exhaust streams of coal-burning power plants, which are the sources of more than 90 percent of all anthropogenic airborne mercury.

  20. NOBLE GAS PRODUCTION FROM MERCURY SPALLATION AT SNS

    SciTech Connect

    DeVore, Joe R; Lu, Wei; Schwahn, Scott O

    2013-01-01

    Calculations for predicting the distribution of the products of spallation reactions between high energy protons and target materials are well developed and are used for design and operational applications in many projects both within DOE and in other arenas. These calculations are based on theory and limited experimental data that verifies rates of production of some spallation products exist. At the Spallation Neutron Source, a helium stream from the mercury target flows through a system to remove radioactivity from this mercury target offgas. The operation of this system offers a window through which the production of noble gases from mercury spallation by protons may be observed. This paper describes studies designed to measure the production rates of twelve noble gas isotopes within the Spallation Neutron Source mercury target.

  1. A screening-level mercury deposition model for wetland ecosystems

    SciTech Connect

    Fink, L.E.

    1995-12-31

    A highly aggregated, three-compartment, carbon cycling model was constructed for a screening-level simulation of net carbon, phosphorus, and mercury deposition in the Everglades Nutrient Removal Project, a 3,742-acre constructed wetland in South Florida. The model was initialized using ENR or Everglades values for model variables. The model was calibrated to calculate biomass turnover, decomposition, and release rates that reproduced the observed apparent phosphorus settling rate constant and the observed organic and inorganic carbon and total phosphorus concentrations in surface sediments. The mercury deposition rate was calculated by partitioning water column mercuric ion onto settling organic and inorganic carbon particles using site-specific or literature values for partition coefficients. From the annual mass balance budget for total mercury calculated with site-specific or literature values, the phosphorus-calibrated model reproduced the observed total mercury concentrations in surface sediments from a typical Everglades marsh within screening-level tolerances.

  2. Characterizing dry deposition of mercury in urban runoff

    USGS Publications Warehouse

    Fulkerson, M.; Nnadi, F.N.; Chasar, L.S.

    2007-01-01

    Stormwater runoff from urban surfaces often contains elevated levels of toxic metals. When discharged directly into water bodies, these pollutants degrade water quality and impact aquatic life and human health. In this study, the composition of impervious surface runoff and associated rainfall was investigated for several storm events at an urban site in Orlando, Florida. Total mercury in runoff consisted of 58% particulate and 42% filtered forms. Concentration comparisons at the start and end of runoff events indicate that about 85% of particulate total mercury and 93% of particulate methylmercury were removed from the surface before runoff ended. Filtered mercury concentrations showed less than 50% reduction of both total and methylmercury from first flush to final flush. Direct comparison between rainfall and runoff at this urban site indicates dry deposition accounted for 22% of total inorganic mercury in runoff. ?? 2007 Springer Science+Business Media B.V.

  3. Mercury cycling in terrestrial watersheds

    USGS Publications Warehouse

    Shanley, James B.; Bishop, Kevin

    2012-01-01

    This chapter discusses mercury cycling in the terrestrial landscape, including inputs from the atmosphere, accumulation in soils and vegetation, outputs in streamflow and volatilization, and effects of land disturbance. Mercury mobility in the terrestrial landscape is strongly controlled by organic matter. About 90% of the atmospheric mercury input is retained in vegetation and organic matter in soils, causing a buildup of legacy mercury. Some mercury is volatilized back to the atmosphere, but most export of mercury from watersheds occurs by streamflow. Stream mercury export is episodic, in association with dissolved and particulate organic carbon, as stormflow and snowmelt flush organic-rich shallow soil horizons. The terrestrial landscape is thus a major source of mercury to downstream aquatic environments, where mercury is methylated and enters the aquatic food web. With ample organic matter and sulfur, methylmercury forms in uplands as well—in wetlands, riparian zones, and other anoxic sites. Watershed features (topography, land cover type, and soil drainage class) are often more important than atmospheric mercury deposition in controlling the amount of stream mercury and methylmercury export. While reductions in atmospheric mercury deposition may rapidly benefit lakes, the terrestrial landscape will respond only over decades, because of the large stock and slow turnover of legacy mercury. We conclude with a discussion of future scenarios and the challenge of managing terrestrial mercury.

  4. Method of controlling the mercury vapor pressure in a photo-chemical lamp or vapor filter used for Hg.sup.196 enrichment

    DOEpatents

    Grossman, Mark W.

    1993-01-01

    The present invention is directed to a method of eliminating the cold spot zones presently used on Hg.sup.196 isotope separation lamps and filters by the use of a mercury amalgams, preferably mercury - indium amalgams. The use of an amalgam affords optimization of the mercury density in the lamp and filter of a mercury enrichment reactor, particularly multilamp enrichment reactors. Moreover, the use of an amalgam in such lamps and/or filters affords the ability to control the spectral line width of radiation emitted from lamps, a requirement for mercury enrichment.

  5. Method of controlling the mercury vapor pressure in a photo-chemical lamp or vapor filter used for Hg[sup 196] enrichment

    DOEpatents

    Grossman, M.W.

    1993-02-16

    The present invention is directed to a method of eliminating the cold spot zones presently used on Hg[sup 196] isotope separation lamps and filters by the use of a mercury amalgams, preferably mercury - indium amalgams. The use of an amalgam affords optimization of the mercury density in the lamp and filter of a mercury enrichment reactor, particularly multilamp enrichment reactors. Moreover, the use of an amalgam in such lamps and/or filters affords the ability to control the spectral line width of radiation emitted from lamps, a requirement for mercury enrichment.

  6. Potassium permanganate for mercury vapor environmental control

    NASA Technical Reports Server (NTRS)

    Kuivinen, D. E.

    1972-01-01

    Potassium permanganate (KMnO4) was evaluated for application in removing mercury vapor from exhaust air systems. The KMnO4 may be used in water solution with a liquid spray scrubber system or as a solid adsorber bed material when impregnated onto a zeolite. Air samples contaminated with as much as 112 mg/cu m of mercury were scrubbed to 0.06mg/cum with the KMnO4-impregnated zeolite (molecular sieve material). The water spray solution of permanganate was also found to be as effective as the impregnated zeolite. The KMnO4-impregnated zeolite was applied as a solid adsorber material to (1) a hardware decontamination system, (2) a model incinerator, and (3) a high vacuum chamber for ion engine testing with mercury as the propellant. A liquid scrubber system was also applied in an incinerator system. Based on the results of these experiments, it is concluded that the use of KMnO4 can be an effective method for controlling noxious mercury vapor.

  7. ULF Waves at Mercury

    NASA Astrophysics Data System (ADS)

    Kim, E.-H.; Boardsen, S. A.; Johnson, J. R.; Slavin, J. A.

    2016-02-01

    This chapter provides a brief overview of the observed characteristics of ultra-low-frequency (ULF) waves at Mercury. It shows how field-aligned propagating ULF waves at Mercury can be generated by externally driven fast compressional waves (FWs) via mode conversion at the ion-ion hybrid resonance. Then, the chapter reviews the interpretation that the strong magnetic compressional waves near and its harmonics observed with 20 of Mercury's magnetic equator could be the ion Bernstein wave (IBW) mode. A recent statistical study of ULF waves at Mercury based on MESSENGER data reported the occurrence and polarization of the detected waves. The chapter further introduces the field line resonance and the electromagnetic ion Bernstein waves to explain such waves, and shows that both theories can partially explain the observations.

  8. Mercury's Caloris Basin

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Mercury: Computer Photomosaic of the Caloris Basin

    The largest basin on Mercury (1300 km or 800 miles across) was named Caloris (Greek for 'hot') because it is one of the two areas on the planet that face the Sun at perihelion.

    The Image Processing Lab at NASA's Jet Propulsion Laboratory produced this photomosaic using computer software and techniques developed for use in processing planetary data. The Mariner 10 spacecraft imaged the region during its initial flyby of the planet.

    The Mariner 10 spacecraft was launched in 1974. The spacecraft took images of Venus in February 1974 on the way to three encounters with Mercury in March and September 1974 and March 1975. The spacecraft took more than 7,000 images of Mercury, Venus, the Earth and the Moon during its mission.

    The Mariner 10 Mission was managed by the Jet Propulsion Laboratory for NASA's Office of Space Science in Washington, D.C.

  9. FDA: Anti-Aging, Skin-Lightening Products May Contain Mercury

    MedlinePlus

    ... medlineplus.gov/news/fullstory_160237.html FDA: Anti-Aging, Skin-Lightening Products May Contain Mercury How you ... is often found in cosmetics marketed as "anti-aging" or "skin lightening" that claim to remove age ...

  10. Mercury regulation, fate, transport, transformation, and abatement within cement manufacturing facilities: review.

    PubMed

    Sikkema, Joel K; Alleman, James E; Ong, Say Kee; Wheelock, Thomas D

    2011-09-15

    The USEPA's 2010 mercury rule, which would reduce emissions from non-hazardous waste burning cement manufacturing facilities by an estimated 94%, represents a substantial regulatory challenge for the industry. These regulations, based on the performance of facilities that benefit from low concentrations of mercury in their feedstock and fuel inputs (e.g., limestone concentration was less than 25 ppb at each facility), will require non-compliant facilities to develop innovative controls. Control development is difficult because each facility's emissions must be assessed and simple correlation to mercury concentrations in limestone or an assumption of 'typically observed' mercury concentrations in inputs are unsupported by available data. Furthermore, atmospheric emissions are highly variable due to an internal control mechanism that captures and loops mercury between the high-temperature kiln and low-temperature raw materials mill. Two models have been reported to predict emissions; however, they have not been benchmarked against data from the internal components that capture mercury and do not distinguish between mercury species, which have different sorption and desorption properties. Control strategies include technologies applied from other industries and technologies developed specifically for cement facilities. Reported technologies, listed from highest to lowest anticipated mercury removal, include purge of collected dust or raw meal, changes in feedstocks and fuels, wet scrubbing, cleaning of mercury enriched dust, dry sorbent injection, and dry and semi-dry scrubbing. The effectiveness of these technologies is limited by an inadequate understanding of sorption, desorption, and mercury species involved in internal loop mercury control. To comply with the mercury rule and to improve current mercury control technologies and practices, research is needed to advance fundamental knowledge regarding mercury species sorption and desorption dynamics on materials

  11. Mercury CEM Calibration

    SciTech Connect

    John F. Schabron; Joseph F. Rovani; Susan S. Sorini

    2007-03-31

    The Clean Air Mercury Rule (CAMR) which was published in the Federal Register on May 18, 2005, requires that calibration of mercury continuous emissions monitors (CEMs) be performed with NIST-traceable standards. Western Research Institute (WRI) is working closely with the Electric Power Research Institute (EPRI), the National Institute of Standards and Technology (NIST), and the Environmental Protection Agency (EPA) to facilitate the development of the experimental criteria for a NIST traceability protocol for dynamic elemental mercury vapor generators. The traceability protocol will be written by EPA. Traceability will be based on the actual analysis of the output of each calibration unit at several concentration levels ranging from about 2-40 ug/m{sup 3}, and this analysis will be directly traceable to analyses by NIST using isotope dilution inductively coupled plasma/mass spectrometry (ID ICP/MS) through a chain of analyses linking the calibration unit in the power plant to the NIST ID ICP/MS. Prior to this project, NIST did not provide a recommended mercury vapor pressure equation or list mercury vapor pressure in its vapor pressure database. The NIST Physical and Chemical Properties Division in Boulder, Colorado was subcontracted under this project to study the issue in detail and to recommend a mercury vapor pressure equation that the vendors of mercury vapor pressure calibration units can use to calculate the elemental mercury vapor concentration in an equilibrium chamber at a particular temperature. As part of this study, a preliminary evaluation of calibration units from five vendors was made. The work was performed by NIST in Gaithersburg, MD and Joe Rovani from WRI who traveled to NIST as a Visiting Scientist.

  12. Mercury iodide crystal growth

    NASA Technical Reports Server (NTRS)

    Cadoret, R.

    1982-01-01

    The purpose of the Mercury Iodide Crystal Growth (MICG) experiment is the growth of near-perfect single crystals of mercury Iodide (HgI2) in a microgravity environment which will decrease the convection effects on crystal growth. Evaporation and condensation are the only transformations involved in this experiment. To accomplish these objectives, a two-zone furnace will be used in which two sensors collect the temperature data (one in each zone).

  13. To Mercury dynamics

    NASA Astrophysics Data System (ADS)

    Barkin, Yu. V.; Ferrandiz, J. M.

    Present significance of the study of rotation of Mercury considered as a core-mantle system arises from planned Mercury missions. New high accurate data on Mercury's structure and its physical fields are expected from BepiColombo mission (Anselmi et al., 2001). Investigation of resonant rotation of Mercury, begun by Colombo G. (1966), will play here main part. New approaches to the study of Mercury dynamics and the construction of analytical theory of its resonant rotation are suggested. Within these approaches Mercury is considered as a system of two non-spherical interacting bodies: a core and a mantle. The mantle of Mercury is considered as non-spherical, rigid (or elastic) layer. Inner shell is a liquid core, which occupies a large ellipsoidal cavity of Mercury. This Mercury system moves in the gravitational field of the Sun in resonant traslatory-rotary regime of the resonance 3:2. We take into account only the second harmonic of the force function of the Sun and Mercury. For the study of Mercury rotation we have been used specially designed canonical equations of motion in Andoyer and Poincare variables (Barkin, Ferrandiz, 2001), more convenient for the application of mentioned methods. Approximate observational and some theoretical evaluations of the two main coefficients of Mercury gravitational field J_2 and C22 are known. From observational data of Mariner-10 mission were obtained some first evaluations of these coefficients: J_2 =(8± 6)\\cdot 10-5(Esposito et al., 1977); J_2 =(6± 2)\\cdot 10-5and C22 =(1.0± 0.5)\\cdot 10-5(Anderson et al., 1987). Some theoretical evaluation of ratio of these coefficients has been obtained on the base of study of periodic motions of the system of two non-spherical gravitating bodies (Barkin, 1976). Corresponding values of coefficients consist: J_2 =8\\cdot 10-5and C22 =0.33\\cdot 10-5. We have no data about non-sphericity of inner core of Mercury. Planned missions to Mercury (BepiColombo and Messenger) promise to

  14. Progress and Future Plans for Mercury Remediation at the Y-12 National Security Complex, Oak Ridge, Tennessee - 13059

    SciTech Connect

    Wilkerson, Laura O.; DePaoli, Susan M.; Turner, Ralph

    2013-07-01

    The U.S. Department of Energy (DOE), along with the Tennessee Department of Environment and Conservation (TDEC) and the U.S. Environmental Protection Agency (EPA), has identified mercury contamination at the Y-12 National Security Complex (Y-12) as the highest priority cleanup risk on the Oak Ridge Reservation (ORR). The historic loss of mercury to the environment dwarfs any other contaminant release on the ORR. Efforts over the last 20 years to reduce mercury levels leaving the site in the surface waters of Upper East Fork Poplar Creek (UEFPC) have not resulted in a corresponding decrease in mercury concentrations in fish. Further reductions in mercury surface water concentrations are needed. Recent stimulus funding through the American Recovery and Reinvestment Act of 2009 (ARRA) has supported several major efforts involving mercury cleanup at Y-12. Near-term implementation activities are being pursued with remaining funds and include design of a centrally located mercury treatment facility for waterborne mercury, treatability studies on mercury-contaminated soils, and free mercury removal from storm drains. Out-year source removal will entail demolition/disposal of several massive uranium processing facilities along with removal and disposal of underlying contaminated soil. As a National Priorities List (NPL) site, cleanup is implemented under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) and directed by the Federal Facility Agreement (FFA) between DOE, EPA, and TDEC. The CERCLA process is followed to plan, reach approval, implement, and monitor the cleanup. (authors)

  15. Low-Cost Options for Moderate Levels of Mercury Control

    SciTech Connect

    Sharon Sjostrom

    2006-03-31

    On March 15, 2005, EPA issued the Clean Air Mercury Rule, requiring phased-in reductions of mercury emissions from electric power generators. ADA-ES, Inc., with support from DOE/NETL and industry partners, is conducting evaluations of EPRI's TOXECON II{trademark} process and of high-temperature reagents and sorbents to determine the capabilities of sorbent/reagent injection, including activated carbon, for mercury control on different coals and air emissions control equipment configurations. DOE/NETL targets for total mercury removal are {ge}55% (lignite), {ge}65% (subbituminous), and {ge}80% (bituminous). Based on work done to date at various scales, meeting the removal targets appears feasible. However, work needs to progress to more thoroughly document and test these promising technologies at full scale. This is the final site report for tests conducted at MidAmerican's Louisa Station, one of three sites evaluated in this DOE/NETL program. The other two sites in the program are MidAmerican's Council Bluff Station and Entergy's Independence Station. MidAmerican's Louisa Station burns Powder River Basin (PRB) coal and employs hot-side electrostatic precipitators with flue gas conditioning for particulate control. This part of the testing program evaluated the effect of reagents used in the existing flue gas conditioning on mercury removal.

  16. FGD Additives to Segregate and Sequester Mercury in Solid Byproducts - Final Report

    SciTech Connect

    Searcy, K; Bltyhe, G M; Steen, W A

    2012-02-28

    Many mercury control strategies for U.S. coal-fired power generating plants involve co-benefit capture of oxidized mercury from flue gases treated by wet flue gas desulfurization (FGD) systems. For these processes to be effective at overall mercury control, the captured mercury must not be re-emitted to the atmosphere or into surface or ground water. The project sought to identify scrubber additives and FGD operating conditions under which mercury re-emissions would decrease and mercury would remain in the liquor and be blown down from the system in the chloride purge stream. After exiting the FGD system, mercury would react with precipitating agents to form stable solid byproducts and would be removed in a dewatering step. The FGD gypsum solids, free of most of the mercury, could then be disposed or processed for reuse as wallboard or in other beneficial reuse. The project comprised extensive bench-scale FGD scrubber tests in Phases I and II. During Phase II, the approaches developed at the bench scale were tested at the pilot scale. Laboratory wastewater treatment tests measured the performance of precipitating agents in removing mercury from the chloride purge stream. Finally, the economic viability of the approaches tested was evaluated.

  17. Method and apparatus for monitoring mercury emissions

    DOEpatents

    Durham, Michael D.; Schlager, Richard J.; Sappey, Andrew D.; Sagan, Francis J.; Marmaro, Roger W.; Wilson, Kevin G.

    1997-01-01

    A mercury monitoring device that continuously monitors the total mercury concentration in a gas. The device uses the same chamber for converting speciated mercury into elemental mercury and for measurement of the mercury in the chamber by radiation absorption techniques. The interior of the chamber is resistant to the absorption of speciated and elemental mercury at the operating temperature of the chamber.

  18. Method and apparatus for monitoring mercury emissions

    DOEpatents

    Durham, M.D.; Schlager, R.J.; Sappey, A.D.; Sagan, F.J.; Marmaro, R.W.; Wilson, K.G.

    1997-10-21

    A mercury monitoring device that continuously monitors the total mercury concentration in a gas. The device uses the same chamber for converting speciated mercury into elemental mercury and for measurement of the mercury in the chamber by radiation absorption techniques. The interior of the chamber is resistant to the absorption of speciated and elemental mercury at the operating temperature of the chamber. 15 figs.

  19. Demonstration Results on the Effects of Mercury Speciation on the Stabilization of Wastes

    SciTech Connect

    Conley, T.B.; Hulet, G.A.; Morris, M.I.; Osborne-Lee, I.W.

    1999-06-01

    Mercury-contaminated wastes are currently being stored at approximately 19 Department of Energy sites, the volume of which is estimated to be about 16m(sup)3. These wastes exist in various forms including soil, sludges, and debris, which present a particular challenge regarding possible mercury stabilization methods. This reports provides the test results of three vendors, Allied Technology Group, IT Corporation, and Nuclear Fuel Services, Inc., that demonstrate the effects of mercury speciation on the stabilization of the mercury wastes. Mercury present in concentrations that exceed 260 parts per million must be removed by extraction methods and requires stabilization to ensure that the final wasteforms leach less than 0.2mg/L of mercury by the Toxicity Characteristic Leaching Procedure or 0.025 mg/L using the Universal Treatment Standard.

  20. Komatiites as Mercury surface analogues: Spectral measurements at PEL

    NASA Astrophysics Data System (ADS)

    Maturilli, Alessandro; Helbert, Jörn; St. John, James M.; Head, James W.; Vaughan, William M.; D'Amore, Mario; Gottschalk, Matthias; Ferrari, Sabrina

    2014-07-01

    The elemental composition of Mercury's surface, which has been recently measured by the NASA MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft, suggests a mineralogy dominated by magnesium-rich orthopyroxene and feldspar. The most magnesium-rich and aluminium-poor regions of Mercury's surface (which are presumably orthopyroxene-rich) have compositions, and possibly mineralogies, analogous to terrestrial boninites and basaltic komatiites. Unfortunately, little is known about the spectral properties of komatiites, especially at the high surface temperatures of Mercury. We therefore have collected three terrestrial komatiites with different compositions plus a synthetic komatiitic sample, and measured their reflectances in the visible and thermal infrared spectral ranges. Samples divided into four grain size ranges (when enough material was available) were measured fresh and after thermal processing in vacuum (10 Pa) at 500 °C, comparable to Mercury peak surface temperatures. Our measurements show that spectral changes between fresh and thermally processed samples occur in both spectral channels, but are stronger in the visible range, with reddening affecting all the samples, while darkening is more selective. It is important to note that darkening and reddening after thermally processing the samples are independent of the komatiites ferrous iron content. In fact the synthetic sample which is nearly iron-free is most strongly affected. From our study it turns out that thermally processing the samples in vacuum at Mercury surface temperature produces the removal of samples' colour centres. The results of our study show also that the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) instrument on MESSENGER orbiting Mercury currently cannot distinguish between different compositions of komatiites, while the future MErcury Radiometer and Thermal infrared Imaging Spectrometer (MERTIS) on the upcoming ESA Bepi

  1. GEOCHEMICAL FACTORS GOVERNING METHYL MERCURY PRODUCTION IN MERCURY CONTAMINATED SEDIMENTS

    EPA Science Inventory

    Bench scale experiments were conducted to improve our understanding of aquatic mercury transformation processes (biotic and abiotic), specifically those factors which govern the production of methyl mercury (MeHg) in sedimentary environments. The greatest cause for concern regar...

  2. Multidrug Efflux Transporters Limit Accumulation of Inorganic, but Not Organic, Mercury in Sea Urchin Embryos

    PubMed Central

    Bošnjak, Ivana; Uhlinger, Kevin R.; Heim, Wesley; Smital, Tvrtko; Franekić-Čolić, Jasna; Coale, Kenneth; Epel, David; Hamdoun, Amro

    2011-01-01

    Mercuric compounds are persistent global pollutants that accumulate in marine organisms and in humans who consume them. While the chemical cycles and speciation of mercury in the oceans are relatively well described, the cellular mechanisms that govern which forms of mercury accumulate in cells and why they persist are less understood. In this study we examined the role of multidrug efflux transport in the differential accumulation of inorganic (HgCl2) and organic (CH3HgCl) mercury in sea urchin (Strongylocentrotus purpuratus) embryos. We found that inhibition of MRP/ABCC-type transporters increases intracellular accumulation of inorganic mercury but had no effect on accumulation of organic mercury. Similarly, pharmacological inhibition of metal conjugating enzymes by ligands GST/GSH significantly increases this antimitotic potency of inorganic mercury, but had no effect on the potency of organic mercury. Our results point to MRP-mediated elimination of inorganic mercury conjugates as a cellular basis for differences in the accumulation and potency of the two major forms of mercury found in marine environments. PMID:19924972

  3. Mercury pollution in Malaysia.

    PubMed

    Hajeb, Parvaneh; Jinap, S; Ismail, Ahmad; Mahyudin, Nor Ainy

    2012-01-01

    Although several studies have been published on levels of mercury contamination of the environment, and of food and human tissues in Peninsular Malaysia, there is a serious dearth of research that has been performed in East Malaysia (Sabah and Sarawak). Industry is rapidly developing in East Malaysia, and, hence, there is a need for establishing baseline levels of mercury contamination in environmental media in that part of the country by performing monitoring studies. Residues of total mercury and inorganic in food samples have been determined in nearly all previous studies that have been conducted; however, few researchers have analyzed samples for the presence of methlymercury residues. Because methylmercury is the most toxic form of mercury, and because there is a growing public awareness of the risk posed by methylmercury exposure that is associated with fish and seafood consumption, further monitoring studies on methylmercury in food are also essential. From the results of previous studies, it is obvious that the economic development in Malaysia, in recent years, has affected the aquatic environment of the country. Primary areas of environmental concern are centered on the rivers of the west Peninsular Malaysian coast, and the coastal waters of the Straits of Malacca, wherein industrial activities are rapidly expanding. The sources of existing mercury input to both of these areas of Malaysia should be studied and identified. Considering the high levels of mercury that now exists in human tissues, efforts should be continued, and accelerated in the future, if possible, to monitor mercury contamination levels in the coastal states, and particularly along the west Peninsular Malaysian coast. Most studies that have been carried out on mercury residues in environmental samples are dated, having been conducted 20-30 years ago; therefore, the need to collect much more and more current data is urgent. Furthermore, establishing baseline levels of mercury exposure to

  4. Determination of dry carbon-based sorbent injection for mercury control in utility ESP and baghouses

    SciTech Connect

    Broderick, T.; Haythornthwaite, S.; Bell, W.; Selegue, T.; Perry, M.

    1998-12-31

    Domestic coal-fired power plants emit approximately 40 to 80 metric tons of mercury to the atmosphere annually. The mercury concentration in utility flue gas is in the dilute range of 0.1 to 1 parts per billion. The EPA is assessing whether such low concentrations of mercury emissions from coal-fired utilities pose any significant health risk and whether mercury regulations would be necessary or appropriate. In anticipation of possible mercury control regulations, ADA Technologies (ADA) and TDA Research, Inc (TDA) were funded by the Department of Energy (DOE) to evaluate carbon-based sorbents for mercury control at utility coal-fired power plants. Past investigations of the use of dry carbon-based sorbent injection for mercury control on pilot-scale utility flue gas applications have shown that these sorbents are capable of removing gas-phase mercury. ADA Technologies field-tested the mercury removal capability of several carbon-based sorbents manufactured by TDA. The test facility was a DOE-owned test facility built and operated by ADA at the Public Service Company of Colorado`s Comanche Station in Pueblo, Colorado. The pilot-scale test fixture is a 600-acfm particulate control module that can be configured as an electrostatic precipitator, a pulse-jet baghouse, or a reverse-gas baghouse. It extracts a slipstream of flue gas from a coal-fired utility boiler. Sorbent is injected into the flue gas slipstream upstream of the particulate control module and is removed by the module. ADA evaluated the mercury capture efficiency of the sorbents over a range of flue gas temperatures and injection rates. In addition, the effect of flyash on mercury capture was also investigated. The test facility is configured to take flue gas from either upstream or downstream of Comanche Station`s full-scale reverse-gas baghouse, allowing tests to be conducted with normal-ash or low-ash flue gas.

  5. Catalysts for oxidation of mercury in flue gas

    DOEpatents

    Granite, Evan J.; Pennline, Henry W.

    2010-08-17

    Two new classes of catalysts for the removal of heavy metal contaminants, especially mercury (Hg) from effluent gases. Both of these classes of catalysts are excellent absorbers of HCl and Cl.sub.2 present in effluent gases. This adsorption of oxidizing agents aids in the oxidation of heavy metal contaminants. The catalysts remove mercury by oxidizing the Hg into mercury (II) moieties. For one class of catalysts, the active component is selected from the group consisting of iridium (Ir) and iridum-platinum (Ir/Pt) alloys. The Ir and Ir/Pt alloy catalysts are especially corrosion resistant. For the other class of catalyst, the active component is partially combusted coal or "Thief" carbon impregnated with Cl.sub.2. Untreated Thief carbon catalyst can be self-activating in the presence of effluent gas streams. The Thief carbon catalyst is disposable by means of capture from the effluent gas stream in a particulate collection device (PCD).

  6. Thermal evolution of Mercury: Effects of volcanic heat-piping

    NASA Astrophysics Data System (ADS)

    Multhaup, K.

    2009-09-01

    A 1D thermal evolution model of Mercury is presented. It accounts for stagnant lid convection, mantle differentiation and inner core growth. Early MESSENGER results indicate that—contrary to prior conclusions drawn from Mariner 10 imagery—volcanism has indeed played a significant role in Mercury's past. To study the effects of mantle heat bypassing the stagnant lid by means of volcanic heat-piping, contrasting end-member models are considered. Results show how break-down of mantle convection and onset of inner core growth are influenced by the mode of heat removal. Structural models of present day Mercury are presented. Their dependence on the core sulphur contents predominates that on the choice of mantle heat removal. However, the latter clearly controls the timing of thermal history events.

  7. Mercury contamination from artisanal gold mining in Antioquia, Colombia: The world's highest per capita mercury pollution.

    PubMed

    Cordy, Paul; Veiga, Marcello M; Salih, Ibrahim; Al-Saadi, Sari; Console, Stephanie; Garcia, Oseas; Mesa, Luis Alberto; Velásquez-López, Patricio C; Roeser, Monika

    2011-12-01

    The artisanal gold mining sector in Colombia has 200,000 miners officially producing 30tonnes Au/a. In the Northeast of the Department of Antioquia, there are 17 mining towns and between 15,000 and 30,000 artisanal gold miners. Guerrillas and paramilitary activities in the rural areas of Antioquia pushed miners to bring their gold ores to the towns to be processed in Processing Centers or entables. These Centers operate in the urban areas amalgamating the whole ore, i.e. without previous concentration, and later burn gold amalgam without any filtering/condensing system. Based on mercury mass balance in 15 entables, 50% of the mercury added to small ball mills (cocos) is lost: 46% with tailings and 4% when amalgam is burned. In just 5 cities of Antioquia, with a total of 150,000 inhabitants: Segovia, Remedios, Zaragoza, El Bagre, and Nechí, there are 323 entables producing 10-20tonnes Au/a. Considering the average levels of mercury consumption estimated by mass balance and interviews of entables owners, the mercury consumed (and lost) in these 5 municipalities must be around 93tonnes/a. Urban air mercury levels range from 300ng Hg/m(3) (background) to 1million ng Hg/m(3) (inside gold shops) with 10,000ng Hg/m(3) being common in residential areas. The WHO limit for public exposure is 1000ng/m(3). The total mercury release/emissions to the Colombian environment can be as high as 150tonnes/a giving this country the shameful first position as the world's largest mercury polluter per capita from artisanal gold mining. One necessary government intervention is to cut the supply of mercury to the entables. In 2009, eleven companies in Colombia legally imported 130tonnes of metallic mercury, much of it flowing to artisanal gold mines. Entables must be removed from urban centers and technical assistance is badly needed to improve their technology and reduce emissions. PMID:22000915

  8. MRP2 involvement in renal proximal tubular elimination of methylmercury mediated by DMPS or DMSA

    SciTech Connect

    Zalups, Rudolfs K. Bridges, Christy C.

    2009-02-15

    2, 3-Dimercaptopropane-1-sulfonic acid (DMPS) and meso-2, 3-Dimercaptosuccinic acid (DMSA) are dithiols used to treat humans exposed to methylmercury (CH{sub 3}Hg{sup +}). After treatment, significant amounts of mercury are eliminated rapidly from the kidneys and are excreted in urine. In the present study, we extended our previous studies by testing the hypothesis that MRP2 mediates the secretion of DMPS or DMSA S-conjugates of CH{sub 3}Hg{sup +}. To test this hypothesis, the disposition of mercury was assessed in control and Mrp2-deficient (TR{sup -}) rats exposed intravenously to a 5.0-mg/kg dose of CH{sub 3}HgCl. Twenty-four and 28 h after exposure, groups of four control and four TR{sup -} rats were injected with saline, DMPS, or DMSA. Tissues were harvested 48 h later. Renal and hepatic contents of mercury were greater in saline-injected TR{sup -} rats than in controls. In contrast, the amounts of mercury excreted in urine and feces by TR{sup -} rats were less than those by controls. DMPS and DMSA significantly reduced the renal and hepatic content of mercury in both groups of rats, with the greatest reduction in controls. A significant increase in urinary and fecal excretion of mercury (which was greater in the controls) was also observed. Our findings in inside-out membrane vesicles prepared from hMRP2-transfected Sf9 cells show that uptake of DMPS and DMSA S-conjugates of CH{sub 3}Hg{sup +} was greater in the vesicles containing hMRP2 than in control vesicles. Overall, these dispositional findings indicate that MRP2 does play a role in DMPS- and DMSA-mediated elimination of mercury from the kidney.

  9. MESSENGER: Exploring Mercury's Magnetosphere

    NASA Technical Reports Server (NTRS)

    Slavin, James A.; Krimigis, Stamatios M.; Acuna, Mario H.; Anderson, Brian J.; Baker, Daniel N.; Koehn, Patrick L.; Korth, Haje; Levi, Stefano; Mauk, Barry H.; Solomon, Sean C.; Zurbuchen, Thomas H.

    2005-01-01

    The MESSENGER mission to Mercury offers our first opportunity to explore this planet s miniature magnetosphere since the brief flybys of Mariner 10. Mercury s magnetosphere is unique in many respects. The magnetosphere of Mercury is among the smallest in the solar system; its magnetic field typically stands off the solar wind only - 1000 to 2000 km above the surface. For this reason there are no closed drift paths for energetic particles and, hence, no radiation belts. The characteristic time scales for wave propagation and convective transport are short and kinetic and fluid modes may be coupled. Magnetic reconnection at the dayside magnetopause may erode the subsolar magnetosphere allowing solar wind ions to impact directly the regolith. Inductive currents in Mercury s interior may act to modify the solar wind interaction by resisting changes due to solar wind pressure variations. Indeed, observations of these induction effects may be an important source of information on the state of Mercury s interior. In addition, Mercury s magnetosphere is the only one with its defining magnetic flux tubes rooted in a planetary regolith as opposed to an atmosphere with a conductive ionospheric layer. This lack of an ionosphere is probably the underlying reason for the brevity of the very intense, but short-lived, - 1-2 min, substorm-like energetic particle events observed by Mariner 10 during its first traversal of Mercury s magnetic tail. Because of Mercury s proximity to the sun, 0.3 - 0.5 AU, this magnetosphere experiences the most extreme driving forces in the solar system. All of these factors are expected to produce complicated interactions involving the exchange and re-cycling of neutrals and ions between the solar wind, magnetosphere, and regolith. The electrodynamics of Mercury s magnetosphere are expected to be equally complex, with strong forcing by the solar wind, magnetic reconnection at the magnetopause and in the tail, and the pick-up of planetary ions all

  10. Determination of mercurous chloride and total mercury in mercury ores

    USGS Publications Warehouse

    Fahey, J.J.

    1937-01-01

    A method for the determination of mercurous chloride and total mercury on the same sample is described. The mercury minerals are volatilized in a glass tube and brought into intimate contact with granulated sodium carbonate. The chlorine is fixed as sodium chloride, determined with silver nitrate, and computed to mercurous chloride. The mercury is collected on a previously weighed gold coil and weighed.

  11. Nutrient Removal in Wastewater Treatment

    ERIC Educational Resources Information Center

    Shah, Kanti L.

    1973-01-01

    Discusses the sources and effects of nutrients in wastewater, and the methods of their removal in wastewater treatment. In order to conserve water resources and eliminate the cost of nutrient removal, treated effluent should be used wherever possible for irrigation, since it contains all the ingredients for proper plant growth. (JR)

  12. Treatment of Mercury Contaminated Oil from Sandia National Laboratory

    SciTech Connect

    Klasson, KT

    2002-05-28

    First Article Tests of a stabilization method for greater than 260 mg mercury/kg oil were performed under a treatability study. This alternative treatment technology will address treatment of U.S. Department of Energy (DOE) organics (mainly used pump oil) contaminated with mercury and other heavy metals. Some of the oil is also co-contaminated with tritium, other radionuclides, and hazardous materials. The technology is based on contacting the oil with a sorbent powder (Self-Assembled Mercaptan on Mesoporous Support, SAMMS), proven to adsorb heavy metals, followed by stabilization of the oil/powder mixture using a stabilization agent (Nochar N990). Two variations of the treatment technology were included in the treatability study. The SAMMS (Self-Assembled Mercaptan on Mesoporous Silica) technology was developed by the Pacific Northwest National Laboratory for removal and stabilization of RCRA metals (i.e., lead, mercury, cadmium, silver, etc.) and for removal of mercury from organic solvents [1]. The SAMMS material is based on self-assembly of functionalized monolayers on mesoporous oxide surfaces. The unique mesoporous oxide supports provide a high surface area, thereby enhancing the metal-loading capacity. SAMMS material has high flexibility in that it binds with different forms of mercury, including metallic, inorganic, organic, charged, and neutral compounds [1] The material removes mercury from both organic wastes, such as pump oils, and from aqueous wastes. Mercury-loaded SAMMS not only passes TCLP tests, but also has good long-term durability as a waste form because: (1) the covalent binding between mercury and SAMMS has good resistance in ion-exchange, oxidation, and hydrolysis over a wide pH range and (2) the uniform and small pore size of the mesoporous silica prevents bacteria from solubilizing the bound mercury. Nochar's N990 Petrobond (Nochar, Inc., Indianapolis, IN) is an oil stabilization agent, specifically formulated for stabilizing vacuum pump

  13. Biogeochemistry: Better living through mercury

    NASA Astrophysics Data System (ADS)

    Schaefer, Jeffra K.

    2016-02-01

    Mercury is a toxic element with no known biological function. Laboratory studies demonstrate that mercury can be beneficial to microbial growth by acting as an electron acceptor during photosynthesis.

  14. Mercury speciation and distribution in a 660-megawatt utility boiler in Taiwan firing bituminous coals.

    PubMed

    Hsi, Hsing-Cheng; Lee, Hsiu-Hsia; Hwang, Jyh-Feng; Chen, Wang

    2010-05-01

    Mercury speciation and distribution in a 660-MW tangential-fired utility boiler in Taiwan burning Australian and Chinese bituminous coal blends was investigated. Flue gases were simultaneously sampled at the selective catalytic reduction (SCR) inlet, the SCR outlet, the electrostatic precipitator (ESP) outlet, and the stack. Samplings of coal, lime, bottom ash/slag, fly ash, and gypsum slurry were also conducted. Results indicated that flue gases at the inlet to SCR contained a great potion of particle-bound mercury (Hg(p)), 59-92% of the total mercury. Removal of mercury was not observed for the SCR system. However, repartitioning of mercury species across the SCR occurred that significantly increased the portion of elemental mercury (Hg0) to up to 29% and oxidized mercury (Hg2+) to up to 33% in the SCR outlet gas. Overreporting of Hg(p) at the inlet of SCR may cause the observed repartitioning; the high ammonia/nitric oxide circumstance in the SCR unit was also speculated to cause the mercury desorption from ash particles and subsequent reentrance into the gas phase. ESP can remove up to 99% of Hg(p), and wet flue gas desulfurization (FGD) can remove up to 84% of Hg2+. Mercury mass balances were calculated to range between 81 and 127.4%, with an average of 95.7% wherein 56-82% was in ESP fly ash, 8.7-18.6% was retained in the FGD gypsum, and 6.2-26.1% was emitted from the stack. Data presented here suggest that mercury removal can be largely enhanced by increasing the conversion of Hg0 into Hg(p) and Hg2+. PMID:20480850

  15. Distribution of mercury in the soft tissues of the Blue Tilapia Oreochromis aureus (Steindachner) after acute exposure to mercury (II) chloride

    SciTech Connect

    Allen, P.

    1994-11-01

    Mercury has no known biological functions in the animal body and is described as an ultratrace element. Consequently, there is no well defined regulatory mechanism present in the animal body and it tends to accumulate readily if available in an animal's environment. Sources of mercury include the chloroalkali industry, the manufacture of electrical equipment, paint, fungicides and dentistry. The use of mercury in the gold mining industry has caused extensive pollution in the Amazon Basin. Whether fish take up organic or inorganic mercury, most of it accumulates in the tissues in the organic form. Most cases of mercury poisoning arising from fish consumption are due to methylmercury because mercury entering the aquatic system rapidly becomes methylated. Minamata disease in humans was first reported in 1956 due to consumption of contaminated fish and shellfish from Minamata Bay. Therefore it is important to monitor the mercury content of fish which are caught or farmed for human consumption. Since many commercial animal feeds contain a fish meal component, monitoring is important from the aspect of contamination of farm animals intended for human consumption. Oreochromis aureus (Steindachner) is a species of tilapia often cultured in ponds and also in cages in North and Latin America. Therefore, it is a suitable model to use for studying the effects of mercury exposure on the distribution of mercury in different tissues of fish. Distribution is important, because different cultures consume different fish organs, not just the muscle portion alone. The tissues which have a high content of mercury will be most dangerous from a toxicological viewpoint. Removal of the tissues known to contain the highest concentrations of mercury would reduce the mercury content of fish meal. Since fish are often species-specific in their responses to heavy metals, it is important to study a species which is actually farmed and cultured as a food fish. 20 refs., 2 tabs.

  16. Evaluation of Mercury Emissions from Coal-Fired Facilities with SCR and FGD Systems

    SciTech Connect

    J. A. Withum; S. C. Tseng; J. E. Locke

    2006-01-31

    CONSOL Energy Inc., Research & Development (CONSOL), with support from the U.S. Department of Energy, National Energy Technology Laboratory (DOE) and the Electric Power Research Institute (EPRI), is evaluating the effects of selective catalytic reduction (SCR) on mercury (Hg) capture in coal-fired plants equipped with an electrostatic precipitator (ESP)--wet flue gas desulfurization (FGD) combination or a spray dyer absorber--fabric filter (SDA-FF) combination. In this program CONSOL is determining mercury speciation and removal at 10 coal-fired facilities. The principal purpose of this work is to develop a better understanding of the potential mercury removal ''co-benefits'' achieved by NO{sub x}, and SO{sub 2} control technologies. It is expected that these data will provide the basis for fundamental scientific insights into the nature of mercury chemistry in flue gas, the catalytic effect of SCR systems on mercury speciation and the efficacy of different FGD technologies for mercury capture. Ultimately, this insight could help to design and operate SCR and FGD systems to maximize mercury removal. The objectives are (1) to evaluate the effect of SCR on mercury capture in the ESP-FGD and SDA-FF combinations at coal-fired power plants, (2) evaluate the effect of SCR catalyst degradation on mercury capture; (3) evaluate the effect of low load operation on mercury capture in an SCR-FGD system, and (4) collect data that could provide the basis for fundamental scientific insights into the nature of mercury chemistry in flue gas, the catalytic effect of SCR systems on mercury speciation and the efficacy of different FGD technologies for mercury capture. This document, the ninth in a series of topical reports, describes the results and analysis of mercury sampling performed on Unit 1 at Plant 7, a 566 MW unit burning a bituminous coal containing 3.6% sulfur. The unit is equipped with a SCR, ESP, and wet FGD to control NO{sub x}, particulate, and SO{sub 2} emissions

  17. NOVEL OXIDANT FOR ELEMENTAL MERCURY CONTROL FROM FLUE GAS

    EPA Science Inventory

    The primary objective of this study is to develop and test advanced noncarbonaceous solid sorbent materials suitable for removing the elemental form of mercury from power plant emissions. An efficient and cost-effective novel Hg(0) oxidant was evaluated in a lab-scale fixed-bed ...

  18. Student Exposure to Mercury Vapors.

    ERIC Educational Resources Information Center

    Weber, Joyce

    1986-01-01

    Discusses the problem of mercury vapors caused by spills in high school and college laboratories. Describes a study which compared the mercury vapor levels of laboratories in both an older and a newer building. Concludes that the mercurial contamination of chemistry laboratories presents minimal risks to the students. (TW)

  19. ATMOSPHERIC MERCURY TRANSPORT AND DEPOSITION

    EPA Science Inventory

    The current state of our scientific understanding the mercury cycle tells us that most of the mercury getting into fish comes from atmospheric deposition, but methylation of that mercury in aquatic systems is required for the concentrations in fish to reach harmful levels. We st...

  20. MERCURY IN MARINE LIFE DATABASE

    EPA Science Inventory

    The purpose of the Mercury in Marine Life Project is to organize information on estuarine and marine species so that EPA can better understand both the extent of monitoring for mercury and level of mercury contamination in the biota of coastal environments. This report follows a ...