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Sample records for air addition sosub

  1. Effects of SO/sub 2/ shielding gas additions on GTA weld shape

    SciTech Connect

    Heiple, C.R.; Burgardt, P.

    1985-06-01

    Substantial increases in GTA weld depth/width ratio resulted from small additions of sulfur dioxide (SO/sub 2/) to the torch shielding gas when welding two stainless steels. The improvement was demonstrated on both Types 304 and 21-6-9 austenitic stainless steels, but would be expected for iron-base alloys generally. The weld pool shape achieved was essentially independent of variations in both SO/sub 2/ content of the torch gas and base metal composition when SO/sub 2/ in the shielding gas was in the range of 500 to 1400 ppm. With 700 ppm SO/sub 2/ in the torch gas, less than 30 ppm sulfur was added to an autogenous weld bead. For alloys where this additional sulfur can be tolerated and appropriate measures can be taken to handle the toxic SO/sub 2/, this technique offers a promising way to improve GTA weld joint penetration while suppressing variable penetration.

  2. Hydrolyzed Portland cement clinker and air-cooled blast furnace slag SO{sub 2} sorbents

    SciTech Connect

    Hays, M.D.; Kenney, M.E.

    1999-07-01

    The preparation, morphologies, densities, mean particle sizes, surface areas, compositions, SO{sub 2}-uptakes, calcium utilizations and 100% SO{sub 2} capture times of SO{sub 2} flue gas sorbents derived by the hydrolysis of cement clinker and of air-cooled blast furnace slag are described and discussed. The hydrolyzed clinker sorbent is highly effective. While it is less effective, the slag sorbent, because it is so much cheaper, is the more attractive of the two.

  3. Conceptual HALT (Hydrate Addition at Low Temperature) scaleup design: Capital and operating costs: Part 5. [Hydrate addition at low temperature for the removal of SO/sub 2/

    SciTech Connect

    Babu, M.; Kerivan, D.; Hendrick, C.; Kosek, B.; Tackett, D.; Golightley, M.

    1988-12-01

    Hydrate addition at low temperature (or the HALT process) is a retrofit option for moderate SO/sub 2/ removal efficiency in coal burning utility plants. This dry FGD process involves injecting calcium based dry hydrate particles into flue gas ducting downstream of the air preheater where the flue gas temperature is typically in the range of 280-325/degree/F. This report is comprised of the conceptual scaleup design of the HALT process to a 180 MW and a 500 MW coal fired utility station followed by detailed capital and operating cost estimates. A cost sensitivity analysis of major process variables for the 500 MW unit is also included. 1 fig.

  4. High SO{sub 2} removal efficiency testing. Topical report - results of sodium formate additive tests at New York State Electric & Gas Corporation`s Kintigh Station

    SciTech Connect

    Murphy, J.

    1997-02-14

    Tests were conducted at New York State Gas & Electric`s (NYSEG`s) Kintigh Station to evaluate options for achieving high sulfur dioxide (SO{sub 2}) removal efficiency in the wet limestone flue gas desulfurization (FGD) system. This test program was one of six conducted by the U.S. Department of Energy to evaluate low-capital-cost upgrades to existing FGD systems as a means for utilities to comply with the requirements of the 1990 Clean Air Act Amendments. The upgrade option tested at Kintigh was sodium formate additive. Results from the tests were used to calibrate the Electric Power Research Institute`s (EPRI) FGD PRocess Integration and Simulation Model (FGDPRISM) to the Kintigh scrubber configuration. FGDPRISM was then used to predict system performance for evaluating conditions other than those tested. An economic evaluation was then done to determine the cost effectiveness of various high-efficiency upgrade options. These costs can be compared with the estimated market value of SO{sub 2} allowance or the expected costs of allowances generated by other means, such as fuel switching or new scrubbers, to arrive at the most cost-effective strategy for Clean Air Act compliance.

  5. 5-MW Toronto HALT (Hydrate Addition at Low Temperature) pilot plant testing: Appendices: Part 1-B. [Hydrate addition at low temperture for the removal of SO/sub 2/

    SciTech Connect

    Babu, M.; College, J.; Forsythe, R.; Lee, K.; Herbert, R.; Kanary, D.

    1988-12-01

    ''Hydrate Addition at Low Temperature'' or HALT is a dry calcium-based hydrate injection process for the removal of SO/sub 2/ from flue gases off a sulfur bearing fuel. In this process the hydrate is pneumatically conveyed and injected into the flue gas stream as a dry particulate. The flue gas is cooled downstream of the hydrate injection location by spraying the gas with a stream of finely atomized water droplets. The water is atomized into a fine spray mist by using air under pressure as the atomizing fluid. The waste product from this process is the dry disposable solids which differ considerably from the wet cake solids obtained from a wet FGD process. This report contains appendices of pilot plant testing in the following areas: (a) figures (data as collected at 10 minute intervals), and inlet SO/sub 2/, O/sub 2/, and gas temperature variations, (b) raw data (sample), (c) solids analysis (hydrate, baghouse solids, and ESP Solids), (d) selected analytical methods on (1) microtrac procedure, (2) BET surface area measurement, (3) DuPont photometric SO/sub 2/ analyzer, and (e) corrosion test data.

  6. An analysis of SO{sub 2} emission compliance under the 1990 Clean Air Act Amendments

    SciTech Connect

    Hanson, D.A.; Cilek, C.M.; Pandola, G.; Taxon, T.

    1992-07-01

    The effectiveness of SO{sub 2} emission allowance trading under Title 4 of the 1990 Amendments to the Clean Air Act (CAA) is of great interest due to the innovative nature of this market incentive approach. However, it may be a mistake to frame the compliance problem for a utility as a decision to trade or not. Trading of allowances should be the consequence, not the decision. The two meaningful decision variables for a utility are the control approaches chosen for its units and the amount of allowances to hold in its portfolio of assets for the future. The number allowances to be bought or sold (i.e. traded) is determined by the emission reduction and banking decisions. Our preferred approach is to think of the problem in terms of ABC`s of the 1990 CAA Amendments: abatement strategy, banking, and cost competitiveness. The implications of the general principles presented in this paper on least cost emission reductions and emissions banking to hedge against risk are being simulated with version 2 of the ARGUS model representing the electric utility sector and regional coal supplies and transportation rates. A rational expectations forecast for allowances prices is being computed. The computed allowance price path has the property that demand for allowances by electric utilities for current use or for banking must equal the supply of allowances issued by the federal government or provided as forward market contracts in private market transactions involving non-utility speculators. From this rational expectations equilibrium forecast, uncertainties are being explored using sensitivity tests. Some of the key issues are the amount of scrubbing and when it is economical to install it, the amount of coal switching and how much low sulfur coal premiums will be bid up; and the amount of emission trading within utilities and among different utilities.

  7. 5-MW Toronto HALT (Hydrate Addition at Low Temperature) pilot plant testing: Test results: Part 1-A. [Hydrate addition at low temperature for the removal of SO/sub 2/

    SciTech Connect

    Babu, M.; College, J.; Forsythe, R.; Kerivan, D.; Lee, K.; Herbert, R.; Kanary, D.

    1988-12-01

    ''Hydrate Addition at Low Temperature'' of HALT is a dry calcium- based hydrate injection process for the removal of SO/sub 2/ from flue gases off a sulfur bearing fuel. In this process the hydrate is pneumatically conveyed and injected into the flue gas stream as a dry particulate. The flue gas is cooled downstream of the hydrate injection location by spraying the gas with a stream finely atomized water droplets. The water is atomized into a fine spray mist by using air under pressure as the atomizing fluid. The spray nozzles are specially designed. A 5MW pilot HALT was designed, constructed and operated to demonstrate the viability of the HALT process. The unit was designed to use a baghouse for particulate removal. A rented ESP was used for a pre-scheduled test period for comparison with the baghouse. Tests were conducted to cover all of the following variables: humidification, stoichiometric ratio, approach temperature, flue gas velocity, inlet flue gas SO/sub 2/ concentration, and inlet flue gas temperature. Solids samples of hydrates disposal and ESP waste solids were chemically analyzed and are reported. Hydrate samples were analyzed for particle size distribution and surface area. A two month long duration test operating 24 hours/day was successfully concluded. EPA leachate tests were conducted on the solids waste. Corrosion tests were conducted on coupons installed in the baghouse. 79 figs., 5 tabs.

  8. Effect of Li{sub 2}SO{sub 4} addition on structure and ionic conductivity of lithium borosilicotitanate glasses

    SciTech Connect

    Satpute, N. S.; Deshpande, A. V.

    2014-04-24

    Lithium borosilicotitanate glasses containing Li{sub 2}SO{sub 4} were prepared by melt quenching technique. Electrical conductivity, density, molar volume and glass transition temperature T{sub g} for all the glass samples were measured. IR spectroscopy was used for structural studies of these glasses in the range from 400 to 2000 cm{sub −1}. The conductivity of the Li{sub 2}SO{sub 4} containing glasses was found to be half an order higher than the base glass. The electrical conductivity was interpreted from the point of view of glass structure which suggests that an enhancement in conductivity is due to the incorporation of Li{sub 2}SO{sub 4} in the macromolecular network. The molar volume and glass transition temperature T{sub g} results are found to be in good correlation with conductivity results.

  9. 1. 0 Million Btu combustor testing: Test results: Part 2. [Hydrate Addition at Low Temperature for the removal of SO/sub 2/

    SciTech Connect

    Babu, M.; College, J.; Forsythe, R.; Kanary, D.

    1988-12-01

    ''Hydrate Addition at Low Temperature'' or HALT is a dry calcium- based hydrate injection process for the removal of SO/sub 2/ from flue gases off a sulfur bearing fuel. In this process the hydrate is pneumatically conveyed and injected into the flue gas stream as a dry particulates. The flue gas is cooled downstream of the hydrate injection location by spraying the gas with a stream of finely atomized water droplets. The water is atomized into a fine spray mist by using air under pressure as the atomizing fluid. The waste product from this process is the dry disposable solids which differ considerably from the wet cake solids obtained from a wet FGD process. The HALT test program currently being conducted at Dravo Lime Company and Ohio Edison Company is to be carried out in two stages: (1) Parametric testing on a 1.0 MM BTU/hour combustor, and (2) Follow up long term testing (six months) on a 5 MW unit. The first stage of the program which involves the parametric testing is now completed. Results are presented. 9 refs., 18 figs.

  10. Multi-nozzle humidification tests: Test results: Part 4. [Hydrate addition at low temperature for the removal of SO/sub 2/

    SciTech Connect

    Stouffer, M.

    1988-12-01

    ''Hydrate Addition at Low Temperature'' or HALT is a dry calcium-based hydrate injection process for the removal of SO/sub 2/ from flue gases off a sulfur bearing fuel. In this process the hydrate is pneumatically conveyed and injected into the flue gas stream as a dry particulate. The flue gas is cooled downstream of the hydrate injection by spraying the gas with a stream of finely atomized water droplets. The water is atomized into a fine spray by using air under pressure as the atomizing fluid. The spray nozzles are specially designed. Results are presented on nozzle array field tests conducted using the Dravo HALT unit at Ohio Edison's Toronto station. A method for humidifier scale-up from single-nozzle pilot test data was demonstrated. The method uses arrays of nozzles, with each individual nozzle operated at fixed conditions determined as optimum in the single-nozzle tests. By applying this method, the Consol 8.3-inch pilot humidifier operation with a single Spraying Systems 1/8JJ-J12 nozzle was successfully scaled up to operation of the Dravo 31 x 31-inch humidifier with arrays of up to 46 J12 nozzles. The tests provided data on nozzle deposition and solids dropout that may be useful for large-scale humidifier design. 4 refs., 16 figs., 10 tabs.

  11. Absorption, electrodialysis and additional regeneration in two flue gas SO/sub 2//NO/sub x/ cleanup processes

    SciTech Connect

    Walker, R.J.; Pennline, H.W.

    1987-01-01

    Eleven potential adsorbents for use in the two processes were tested in a laboratory-scale bubble column. Best absorbent performance was obtained with iron EDTA in an ammonium sulfite/sulfate solution. Removals of greater than 95% were observed for SO/sub 2/, NO, and NO/sub 2/ from a simulated flue gas containing N/sub 2/, O/sub 2/, CO/sub 2/, SO/sub 2/, NO, and NO/sub 2/. Laboratory-scale electrodialysis tests of fresh scrubbing liquor revealed that iron EDTA tended to permeate through anion-selective membranes and thus deleteriously affected process performance. Screening tests with twelve types of anion-selective membranes showed that three had EDTA permeation rates that were acceptable for process operation. Two methods of regeneration with respect to the NO/sub x/-removal component were investigated. Thermal stripping did not appear successful for producing nitrogen oxides in the off-gas from the stripper. A thermal treatment of the spent liquor at 50/sup 0/C successfully regenerated iron EDTA. The mechanism is being investigated.

  12. Phytotoxicity of air pollutants: evidence for the photodetoxification of SO/sub 2/ but not O/sub 3/

    SciTech Connect

    Olszyk, D.M.; Tingey, D.T.

    1984-04-01

    Pisum sativum L. cv Alsweet (garden pea) and Lycopersicon esculentum flacca Mill. (tomato) were used to evaluate the phytotoxicity of SO/sub 2/ and O/sub 3/ in the light and dark. Plants were grown in controlled environment chambers and exposed to SO/sub 2/ or O/sub 3/ in the light or dark at the same environmental conditions at which they were grown. The pea plants were treated with fusicoccin to ensure open stomata in the dark; the stomata of the tomato mutant remained open in the dark. Both species exhibited 64% to 80% less foliar necrosis following exposure to SO/sub 2/ (0.5 to 1.0 microliter per liter for 2 hours) in the light than in the dark. The decrease in SO/sub 2/ injury for light versus dark exposed plants was greater in fully expanded than expanding leaves. Both species exhibited 30% greater foliar necrosis following exposure to O/sub 3/ (0.2 microliter per liter for 2 hours) in the light than dark. The increase in O/sub 3/ injury in the light versus dark was similar for leaves at all stages of expansion. Leaf conductance to water vapor was 7% to 11% and 23% higher in the light than dark for fusicoccin-treated peas and tomato plants, respectively, indicating greater foliar uptake of both pollutants in the light than dark. Thus, the decrease SO/sub 2/ toxicity in the light was not associated with pollutant uptake, but rather the metabolism of SO/sub 2/. In contrast, the increased toxicity of O/sub 3/ in the light was at least in part associated with increased uptake or could not be separated from it.

  13. Combined SO{sub 2}/NO{sub x} control using ferrous{center_dot}EDTA and a secondary additive in a lime-based aqueous scrubber system

    SciTech Connect

    Mendelsohn, M.H.; Livengood, C.D.; Harkness, J.B.L.

    1991-12-01

    Integration of NO{sub x} control into existing flue-gas desulfurization (FGD) systems addresses site-specific control requirements while minimizing retrofit difficulties. Argonne has studied the use of the metal-chelate additives, such as ferrous{center_dot}EDTA in various wet FGD chemistries, to promote combined SO{sub 2}/NO{sub x} scrubbing. A major process problem is oxidation of the iron to the ferric species, leading to a significant decrease in NO{sub x}-removal capability. Argonne discovered a class of organic compounds that, when used with ferrous{center_dot}EDTA in a sodium carbonate chemistry, could maintain high levels of NO{sub x} removal. However, those antioxidant/reducing agents are not effective in a lime-based chemistry, and a broader investigation of antioxidants was initiated. This paper discusses results of that investigation, which found a practical antioxidant/reducing agent capable of maintaining NO{sub x} removals of about 50% (compared with about 15% without the agent) in a lime-based FGD chemistry with FE(II){center_dot}EDTA. 5 refs., 10 figs.

  14. Fuel additives from SO/sub 2/ treated mixtures of amides and esters derived from vegetable oil, tall oil acid, or aralkyl acid

    SciTech Connect

    Efner, H. F.; Schiff, S.

    1985-03-12

    Vegetable oils, particularly soybean oil, tall oil acid, or aralkyl acids, particularly phenylstearic acid, are reacted with multiamines, particularly tetraethylenepentamine, to form a product mixture for subsequent reaction with SO/sub 2/ to produce a product mix that has good detergent properties in fuels.

  15. The geography of So{sub 2} emissions trading

    SciTech Connect

    Solomon, B.

    1995-12-01

    Interstate trading of SO{sub 2} emission allowances under the Clean Air Act Amendments of 1990 represents the largest-scale application of market principles to environmental protection. some opponents have hypothesized that high emitting electric power plants in the Midwestern states will buy additional allowances and thereby sustain SO{sub 2} emissions at unacceptable high levels. Much of these emissions would then continue to return downwind as sulfates in the Northeast, damaging critical ecosystems such as lakes and forests in the Adirondacks. A competing hypothesis is that in an increasingly competitive utility industry, a power plant will choose the least-cost compliance option for its SO{sub 2} emission requirements, which for many large and dirty Midwestern plants will be to retrofit with scrubbers. This paper will provide the first comprehensive empirical analysis of the geographic pattern of SO{sub 2} allowance trading for the first three years (early 1992 to early 1995) to determine the validity of the first hypothesis. It will be shown that with the exception of one electric utility in Illinois, the Midwestern states have not used allowance trading to sustain high emission levels. A Congressionally-mandated subsidy for scrubber retrofits at Phase I affected-units, however, has allowed two of these states (Ohio and Indiana) plus three additional Appalachian states (Tennessee, West Virginia and Pennsylvania) to acquire large quantities of bonus allowances. Most of these additional allowances may be banked for future use at other affected units by the acquiring utilities, since the newly scrubbed plants will have much lower SO{sub 2} emissions because of the scrubber retrofits. The good news is that the trading program is projected to save a lot of money, over $2 billion out of a possible $3 billion in annual compliance costs by the time of Phase II.

  16. Regional air quality: local and interstate impacts of NOx and SO{sub 2} emissions on ozone and fine particulate matter in the eastern United States

    SciTech Connect

    Michelle S. Bergin; Jhih-Shyang Shih; Alan J. Krupnick; James W. Boylan; James G. Wilkinson; M. Talat Odman; Armistead G. Russell

    2007-07-01

    While the U.S. air quality management system is largely designed and managed on a state level, many critical air quality problems are now recognized as regional. In particular, concentrations of two secondary pollutants, ozone and particulate matter, are often above regulated levels and can be dependent on emissions from upwind states. Here, impacts of statewide emissions on concentrations of local and downwind states' ozone and fine particulate matter are simulated for three seasonal periods in the eastern United States using a regional Eulerian photochemical model. Impacts of ground level NOx (e.g., mobile and area sources), elevated NOx (e.g., power plants and large industrial sources), and SO{sub 2} emissions are examined. An average of 77% of each state's ozone and PM2.5 concentrations that are sensitive to the emissions evaluated here are found to be caused by emissions from other states. Delaware, Maryland, New Jersey, Virginia, Kentucky, and West Virginia are shown to have high concentrations of ozone and PM2.5 caused by interstate emissions. When weighted by population, New York receives increased interstate contributions to these pollutants and contributions to ozone from local emissions are generally higher. When accounting for emission rates, combined states from the western side of the modeling domain and individual states such as Illinois, Tennessee, Indiana, Kentucky, and Georgia are major contributors to interstate ozone. Ohio, Indiana, Tennessee, Kentucky, and Illinois are the major contributors to interstate PM2.5. When accounting for an equivalent mass of emissions, Tennessee, Kentucky, West Virginia, Virginia, and Alabama contribute large fractions of these pollutants to other states. 46 refs., 9 figs.

  17. Metal-air cell with performance enhancing additive

    SciTech Connect

    Friesen, Cody A; Buttry, Daniel

    2015-11-10

    Systems and methods drawn to an electrochemical cell comprising a low temperature ionic liquid comprising positive ions and negative ions and a performance enhancing additive added to the low temperature ionic liquid. The additive dissolves in the ionic liquid to form cations, which are coordinated with one or more negative ions forming ion complexes. The electrochemical cell also includes an air electrode configured to absorb and reduce oxygen. The ion complexes improve oxygen reduction thermodynamics and/or kinetics relative to the ionic liquid without the additive.

  18. SO.sub.2 sensor

    DOEpatents

    Dalla Betta, Ralph A.; Sheridan, David R.

    1994-01-01

    This invention is a process for detecting low concentration levels of sulfur oxides (SO.sub.2) in a flowing gas stream (typically a combustion exhaust gas stream) and a catalytic SO.sub.2 sensor system which may be used in that process.

  19. High SO{sub 2} removal efficiency testing: Results of DBA and sodium formate additive tests at Southwestern Electric Power company`s Pirkey Station

    SciTech Connect

    1996-05-30

    Tests were conducted at Southwestern Electric Power Company`s (SWEPCo) Henry W. Pirkey Station wet limestone flue gas desulfurization (FGD) system to evaluate options for achieving high sulfur dioxide removal efficiency. The Pirkey FGD system includes four absorber modules, each with dual slurry recirculation loops and with a perforated plate tray in the upper loop. The options tested involved the use of dibasic acid (DBA) or sodium formate as a performance additive. The effectiveness of other potential options was simulated with the Electric Power Research Institute`s (EPRI) FGD PRocess Integration and Simulation Model (FGDPRISM) after it was calibrated to the system. An economic analysis was done to determine the cost effectiveness of the high-efficiency options. Results are-summarized below.

  20. Regenerable solid sorbents for Claus tailgas cleanup: A treatment process for the catalytic removal of SO{sub 2} and H{sub 2}S

    SciTech Connect

    Buchanan, J.S.; Stern, D.L.; Nariman, K.E.; Teitman, G.J.; Sodomin, J.F.; Johnson, D.L.

    1996-08-01

    Use of a regenerable solid sorbent can offer advantages over conventional wet scrubbing for Claus tailgas treatment. In this paper, the authors describe a novel process/catalyst combination for this service. The Mobil Oil SO{sub x} Treatment (MOST) process, demonstrated here on the laboratory scale, consists of first combusting the Claus tailgas with air, converting all sulfur species to SO{sub 2}/SO{sub 3}. The SO{sub x} is then sorbed onto a solid sorbent, and in a separate step, the sulfur is reductively desorbed as a concentrated stream of mainly SO{sub 2} and H{sub 2}S, which can then be recycled to the Claus plant for further processing. Catalyst screening for this application focused on examining alumina and magnesium aluminates, with oxidation promoters including ceria, vanadia, and platinum. The materials with the highest SO{sub x} uptake are a commercial FCC SO{sub x} transfer additive and a vanadia/ceria-promoted, magnesium aluminate (V/Ce/Mg{sub 2}Al{sub 2}O{sub 5}) spinel (54 and 46 wt % SO{sub x} uptake, respectively). During most of the adsorption period, the SO{sub 2} level in the effluent from the sorbent bed was below 1 ppmv. When the same base magnesium aluminate was examined with ceria but without vanadia, the SO{sub x} uptake was lower (25 wt %), while the base alone had fairly low uptake (5 wt %). Thus, effective SO{sub 2} oxidation promoters are necessary for this application. Oxidation of CO to CO{sub 2} was also demonstrated over these catalysts. All materials examined were found to be regenerable under hydrogen. The main products observed were SO{sub 2}, H{sub 2}O, and H{sub 2}S. The results indicate that a regenerable solid sorbent-based SO{sub x} abatement system can give lower emissions of sulfur species and of CO than current Claus treatment processes and may allow a capacity increase in a hydraulically limited Claus plant.

  1. SO{sub 2} control in low emissions boiler systems with the COBRA process

    SciTech Connect

    Breault, R.W.; Litka, A.F.; Beittel, R.

    1995-06-01

    The COBRA process is an advanced embodiment of the chemically well proven copper oxide process. COBRA stands for Copper Oxide Bed Regenerative Adsorber, a moving bed - cross flow configuration which is ideally suited for SO{sub 2} control and NO{sub x}, reduction through its SCR capabilities. The moving bed adsorber provides low sorbent attrition and allows the use of larger sorbent particle sizes for an overall more economical design. The location of the COBRA process between the economizer and the air heater enhances low temperature heat recovery by removing SO{sub 3} in addition to SO{sub 2}, thereby allowing for very low flue gas temperatures. This paper presents the results of a sensitivity analysis aimed at optimizing the design of a 400 Mw system and integration into a low emissions boiler system. It will identify the benefits of the technology, showing how it is possible to achieve a 99% reduction of SO{sub 2} with very low power consumption and produce a salable by-product - either sulfuric acid or elemental sulfur.

  2. Do-It-Yourself Additives Recharge Auto Air Conditioning

    NASA Technical Reports Server (NTRS)

    2010-01-01

    In planning for a return mission to the Moon, NASA aimed to improve the thermal control systems that keep astronauts comfortable and cool while inside a spacecraft. Goddard Space Flight Center awarded a Small Business Innovation Research (SBIR) contract to Mainstream Engineering Corporation, of Rockledge, Florida, to develop a chemical/mechanical heat pump. IDQ Inc., of Garland, Texas, exclusively licensed the technology and incorporates it into its line of Arctic Freeze products for automotive air conditioning applications. While working on the design, Mainstream Engineering came up with a unique liquid additive called QwikBoost to enhance the performance of the advanced heat pump design.

  3. Environmental effects of SO{sub 2} trading and banking

    SciTech Connect

    Burtraw, D.; Mansur, E.

    1999-10-15

    The widely acknowledged innovation of Title IV of the 1990 Clean Air Act Amendments is sulfur dioxide allowance trading, which is designed to encourage the electricity industry to minimize the cost of reducing emissions. Few studies have examined the environmental effects of trading, and none have explored the effects of banking. The authors used an integrated assessment computer model, the Tracking and Analysis Framework, to evaluate changes in emissions of SO{sub 2}, atmospheric concentrations of sulfates and deposition of sulfur, and public health benefits from reduced exposure to SO{sub 2} and particulate matter. They assessed geographic and temporal changes at the state level that result from trading and banking and compared them with estimated cost savings. The findings are not consistent with the feats of the program's critics. In the East and Northeast including New York State, an area of particular concern, the authors found that health benefits increase and sulfur deposition decrease slightly as a result of trading. Nationally, trading results in health-related benefits in addition to significant cost savings. Banking changes the timing of emissions, but the geographic consequence of banking is varied.

  4. Catalytic reduction of SO[sub x]-NO[sub x] in coal flue gas

    SciTech Connect

    Not Available

    1991-11-01

    Almost half of the coal purchased by the utilities that year was not Ohio coal. The 20-plus million tons/year of non-Ohio coal consumed by Ohio generators is an indication of the order of magnitude of the potential market incentive for Ohio to supply its power plants from its indigenous coal mine. The major reason for the drop in Ohio coal production rate is that the average content of Ohio coal is 3.5 weight percent, with a range of one to six percent. Use of high-sulfur coal introduces environmental problems due to the high SO[sub 2] emission rate in the boiler flue gas. Potential solutions include use of alternative low-sulfur non-Ohio coal and addition of SO[sub 2] (and NO[sub x]) removal facilities. The substitution of non-Ohio low-sulfur coal for Ohio coal is a strong negative for the state and its coal mining industry; it means further shrinkage of the state's coal industry accompanied by loss of Ohio jobs. The Parsons FGC process is a candidate for the alternative solution, i.e., to provide high efficiency post-combustion removal of SO[sub 2] (and NO[sub x]). The Phase 2 pilot plant test results have demonstrated that the Parsons FGC process is capable to remove 99-plus percent of SO[sub 2] and 95-plus percent of NO[sub x] from coal-fired boiler flue gas. The Parsons FGC process will permit Ohio coal fired power plants to burn high-sulfur Ohio coal and achieve conformance with provisions of the Clean Air Act Amendments of 1990. Because SO[sub 2] reduction using the Parsons FGC process will be greater than the amendment requirement, its use will provide the affected Ohio power plant with marketable net allowances having a definite economic value.

  5. Calculations from compliance emissions of long- and short-term SO/sub 2/ concentrations in the southwest Pennsylvania air quality control region. Final report 1979-80

    SciTech Connect

    Not Available

    1981-05-01

    This report describes the results of dispersion-model calculations of maximum annual, 24-hour and 3-hour average ground-level SO2 concentrations for selected areas in the Southwest Pennsylvania Air Quality Control Region (AQCR). The primary purpose of the model calculations was to assist EPA Region III and the Pennsylvania Department of Environmental Resources in determining the attainment or non-attainment of the National Ambient Air Quality Standards (NAAQS) for SO2 in the Beaver Valley and Monongahela Valley Air Basins exclusive of Allegheny County. All of the dispersion-model calculations were made using the LONGZ and SHORTZ dispersion models with 1980 compliance emissions inventories containing 492 major SO2 sources located within the Southwest Pennsylvania AQCR and in Ohio and West Virginia near the western border of the AQCR. The only calculated maximum that exceeds the NAAQS for SO2 is the maximum annual average concentration at an isolated grid point located on high terrain about 1 kilometer north of the Monessen Plant of Wheeling-Pittsburgh Steel. The model calculations also indicate contributions of major SO2 sources located along the Ohio River in Ohio and West Virginia to the air quality in the Southwest Pennsylvania AQCR.

  6. Calculations from compliance emissions of long and short term SO/sub 2/ concentrations in the southwest Pennsylvania air quality control region. Final report, 1979 - 1980

    SciTech Connect

    Not Available

    1981-05-01

    The results of dispersion model calculations of maximum annual, 24 hour and 3 hour average ground level SO2 concentrations for selected areas in the region (AQOR) is described. The primary purpose of the model calculations was to assist EPA Region III and the Pennsylvania Department of Environmental Resources in determining the attainment or nonattainment of the National Ambient Air Quality Standards (NAAQS) for SO2 in the Beaver Valley and Monongahela Valley Air Basins exclusive of Allegheny County. All of the dispersion model calculations were made using the LONGZ and SHORTZ dispersion models with 1980 compliance emissions inventories containing 492 major SO2 sources located within the AQOR and in Ohio and West Virginia near the western border of the AQOR.

  7. Bifunctional air electrodes containing elemental iron powder charging additive

    DOEpatents

    Liu, Chia-tsun; Demczyk, Brian G.; Gongaware, Paul R.

    1982-01-01

    A bifunctional air electrode for use in electrochemical energy cells is made, comprising a hydrophilic layer and a hydrophobic layer, where the hydrophilic layer essentially comprises a hydrophilic composite which includes: (i) carbon; (ii) elemental iron particles having a particle size of between about 25 microns and about 700 microns diameter; (iii) an oxygen evolution material; (iv) a nonwetting agent; and (v) a catalyst, where at least one current collector is formed into said composite.

  8. Comparison of orchid and OCD modeling SO{sub x} release in the Gulf of Mexico

    SciTech Connect

    Ferris, D.C.; Burns, D.S.; Steorts, W.L.

    1996-10-01

    Two atmospheric chemistry and transport models are used to investigate the atmospheric behavior of SO{sub x} in the Gulf of Mexico. SO{sub x} emissions from a location about 30 miles offshore in the Gulf of Mexico will be modeled with ENSCO`s Short-range Layered Atmospheric Model (SLAM) and the EPA and Material Management Service (MMS) sanctioned Offshore and Coastal Dispersion Model (OCD). The atmospheric chemistry associated with SLAM is modeled using ENSCO`s ORganic CHemistry Integrated Dispersion Model (ORCHID) and has been developed from the Carbon Bond Mechanism (CBM-IV) to characterize the behavior of SO{sub x} compounds in the environment. Model runs from both ORCHID and OCD will be presented and compared. Predicted SO{sub x} concentrations will be compared with actual data gathered from the MMS`s SO{sub x} air quality study in 1993.

  9. Kinetics of combined SO/sub 2//NO in flue gas clean-up

    SciTech Connect

    Chang, S.G.; Littlejohn, D.

    1985-03-01

    The kinetics of reactions involving SO/sub 2/, NO, and ferrous chelate additives in wet flue gas simultaneous desulfurization and denitrification scrubbers are discussed. The relative importance of these reactions are assessed. The relevance of these reactions to spray dryer processes for combined SO/sub 2//NO flue gas clean-up is addressed. 37 refs., 7 figs.

  10. SO{sub 3}'s impacts on plant O & M: part 1

    SciTech Connect

    Moser, R.E.

    2006-10-15

    The visible consequences of sulfuric acid aerosol emissions, opaque stack emissions called 'blue plumes', are merely the tip of an iceberg. In sufficient concentration, SO{sub 3} also can increase corrosion and fouling of equipment and components downstream of the furnace while decreasing their efficiency and penalizing overall plant heat rate. This article, the first in a three part series, details the negative impacts of SO{sub 3} on operations and maintenance of back-end plant equipment. These include: reduction of unit heat rate and increased corrosion of downstream equipment due to the raising of dew point by SO{sub 3}; fouling of air heaters and SCR catalysts due to the reaction of SO{sub 3} with ammonia and competition of SO{sub 3} with mercury for adsorption sites on carbon particles, reducing the effectiveness of mercury emissions control. Part II will explain and quantify the potential benefits of limiting the concentration of SO{sub 3} in flue gas to 3ppm at the entrance to the air heater. Part III will describe the characteristics of an optimal SO{sub 3} removal technology and present the technical details and operating experience of one patented process that has worked successfully at a half dozen plants for up to three years. 1 ref., 2 figs.

  11. HUMAN HEALTH DAMAGES FROM MOBILE SOURCE AIR POLLUTION: ADDITIONAL DELPHI DATA ANALYSIS. VOLUME II

    EPA Science Inventory

    The report contains the results of additional analyses of the data generated by a panel of medical experts for a study of Human Health Damages from Mobile Source Air Pollution (hereafter referred to as HHD) conducted by the California Air Resources Board in 1973-75 for the U.S. E...

  12. 77 FR 13384 - Additional Guidance on Airfare/Air Tour Price Advertisements; Correction

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-06

    ...The Department published a notice entitled ``Additional Guidance on Airfare/Air Tour Price Advertisements,'' in the Federal Register of February 27, 2012; the notice contained an incorrect address for the...

  13. High-efficiency SO{sub 2} removal in utility FGD systems

    SciTech Connect

    Phillips, J.L.; Gray, S.; Dekraker, D.

    1995-11-01

    The U.S. Department of Energy (DOE) and the Electric Power Research Institute (EPRI) have contracted with Radian Corporation to conduct full-scale testing, process modeling, and economic evaluations of six existing utility flue gas desulfurization (FGD) systems. The project objective is to evaluate low capital cost upgrades for achieving up to 98% sulfur dioxide (SO{sub 2}) removal efficiency in a variety of FGD system types. The systems include dual-loop, packed absorbers at Tampa Electric Company`s Big Bend Station; cocurrent, packed absorbers at Hoosier Energy`s Merom Station; dual-loop absorbers with perforated-plate trays at Southwestern Electric Power Company`s Pirkey Station; horizontal spray absorbers at PSI Energy`s Gibson Station; venturi scrubbers at Duquesne Light`s Elrama Station; and open stray absorbers at New york State Electric and Gas Corporations`s (NYSEG`s) Kintigh Station. All operate in an inhibited-oxidation mode except the system at Big Bend (forced oxidation), and all use limestone reagent except the Elrama system (Mg-lime). The program was conducted to demonstrate that upgrades such as performance additives and/or mechanical modifications can increase system SO{sub 2} removal at low cost. The cost effectiveness of each upgrade has been evaluated on the basis of test results and/or process model predictions for upgraded performance and utility-specific operating and maintenance costs. Results from this upgraded performance and utility-specific operating and maintenance costs. Results from this program may lead some utilities to use SO{sub 2} removal upgrades as an approach for compliance with phase 2 of Title IV of the Clean Air Act Amendments (CAAA) of 1990. This paper summarizes the results of testing, modeling, and economic evaluations that have been completed since July, 1994.

  14. Application of a new sorbent for combined SO{sub 2} and NO{sub x} removal. Final report

    SciTech Connect

    Nelson, S.G.

    1989-09-01

    The overall objective of this project was to further develop the application of a new class of dry, granular, SO{sub 2}/NO{sub x}-sorbent materials to bring them closer towards commercial usage in utility and industrial air-pollution control systems. The new sorbents are composite materials consisting of magnesium oxide (MgO) or calcium oxide (CaO) bonded to and reacted with vermiculite, a low-cost expanded silicate carrier. The sorbents possess some very unique and desirable properties. These properties include a higher-than-normal affinity for sulfur and nitrogen oxides in stack gases, excellent SO{sub 2}-removal efficiencies and attractive utilization rates at common stack gas temperatures, and the ability to be regenerated. The materials typically remove 99 percent of the SO{sub 2} and a significant percentage of the NO{sub x} in flue gases with high sorbent utilizations. Specific objectives of the project were to evaluate the performance of different continuous methods of employing the new sorbent materials in removing SO{sub 2} and NO{sub x} from a power plant flue gas, to examine the regeneration of one particularly promising sorbent composition: 45 wt % MgO-55 wt % Vermiculite, and to develop a sorption-regeneration system and cost estimates based on this material. The objectives were met in the project. The cost of the 15-month project was $229,717, of which OCDO provided $149,972 and Sanitech provided the remainder. In additions Sanitech and Ohio Edison made significant in-kind contributions to the project, in the form of existing facilities and equipment. The results of this project should help move the new technology forward toward commercialization. Required now are scale-ups of the new technology at more meaningful sizes.

  15. RETROFITTING AN AUTOMOTIVE AIR CONDITIONER WITH HFC-134A, ADDITIVE, AND MINERAL OIL

    EPA Science Inventory

    The paper gives results of an evaluation of a lubricant additive developed for use in retrofitting motor vehicle air conditioners. he additive was designed to enable HFC-134a to be used as a retrofit refrigerant with the existing mineral oil in CVC-12 systems. he goal of the proj...

  16. 48 CFR 1352.271-72 - Additional Item Requirements (AIR)-growth work

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 5 2011-10-01 2011-10-01 false Additional Item Requirements (AIR)-growth work 1352.271-72 Section 1352.271-72 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 1352.271-72 Additional Item...

  17. 48 CFR 1352.271-72 - Additional Item Requirements (AIR)-growth work

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 5 2013-10-01 2013-10-01 false Additional Item Requirements (AIR)-growth work 1352.271-72 Section 1352.271-72 Federal Acquisition Regulations System DEPARTMENT OF COMMERCE CLAUSES AND FORMS SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions and Clauses 1352.271-72 Additional Item...

  18. Regulation of adenosine 5'-phosphosulfate sulfotransferase activity by SO/sub 2/ in Rosa cells cultures

    SciTech Connect

    Brunold, C.; Suter, M.

    1986-04-01

    The effect of aeration with 5 ..mu..l l/sup -1/ SO/sub 2/ on extractable activity of adenosine 5'-phosphosulfate sulfotransferase (APSSTase) activity from dark grown suspension cultures of Paul's Scarlet rose (Rosa sp.) was studied. The enzyme activity was at 50% of that of controls after 24 h and at 20% after 48 h. This decrease was only detected, when the pH of the nutrient solution was below 5.8, indicating that SO/sub 2/ rather than SO/sub 3//sup 2 -/ was the active species. The growth rate of the cells was not affected. After omission of SO/sub 2/ APSSTase activity increased to the level of control cultures within 24h. NO/sub 2/ up to 10 ..mu..ll/sup -1/ and Na/sub 2/SO/sub 3/ up to 500 ..mu..M had no effect on APSSTase activity. Addition of ascorbic acid to the culture medium did not affect the decrease in APSSTase activity induced by SO/sub 2/. Their results indicate that the effect of SO/sub 2/ on APSSTase activity is a specific regulatory phenomenon.

  19. The importance of SO{sub 2} and SO{sub 3} for sulphation of gaseous KCl - An experimental investigation in a biomass fired CFB boiler

    SciTech Connect

    Kassman, Haakan; Baefver, Linda; Aamand, Lars-Erik

    2010-09-15

    This paper is based on results obtained during co-combustion of wood pellets and straw in a 12 MW circulating fluidised bed (CFB) boiler. Elemental sulphur (S) and ammonium sulphate ((NH{sub 4}){sub 2}SO{sub 4}) were used as additives to convert the alkali chlorides (mainly KCl) to less corrosive alkali sulphates. Their performance was then evaluated using several measurement tools including, IACM (on-line measurements of gaseous alkali chlorides), a low-pressure impactor (particle size distribution and chemical composition of extracted fly ash particles), and deposit probes (chemical composition in deposits collected). The importance of the presence of either SO{sub 2} or SO{sub 3} for gas phase sulphation of KCl is also discussed. Ammonium sulphate performed significantly better than elemental sulphur. A more efficient sulphation of gaseous KCl was achieved with (NH{sub 4}){sub 2}SO{sub 4} even when the S/Cl molar ratio was less than half compared to sulphur. Thus the presence of gaseous SO{sub 3} is of greater importance than that of SO{sub 2} for the sulphation of gaseous KCl. (author)

  20. Proof of concept testing of an integrated dry injection system for SO{sub 2}/NO{sub x} control. Final report

    SciTech Connect

    Helfritch, D.J.; Bortz, S.J.; Beittel, R.

    1994-03-01

    The integrated Dry Injection Process (IDIP) consists of combustion modification using low NO{sub x} burners to reduce NO{sub x} emissions, dry injection of hydrated line at economizer temperatures for primary capture of SO{sub 2}, dry injection of a commercial grade sodium bicarbonate at the air heater exit for additional SO{sub 2} and NO{sub x} removal, and humidification for precipitator conditioning. IDIP offers the potential for simultaneously achieving 90% SO{sub 2} removal, and 65% NO{sub x} removal from a high sulfur flue gas. The process is well suited for new or retrofit applications since it can be incorporated within existing economizer and downstream ductwork. Subscale tests were performed in order to identify the best calcium and sodium sorbents. These tests involved the injection of calcium hydroxide and sodium sorbents at various points of the flue gas system downstream of a 0.25 MM BTU/hr. coal fired combustor, and the gas residence times, cooling rates and temperatures were comparable to those found for full-scale utility boilers. These tests verified that a high surface area hydrated lime provides maximum sorbent utilization and identified an alcohol-water hydrated lime as yielding the highest surface area and the best SO{sub 2} removal capability. The tests also identified sodium bicarbonate to be somewhat more effective than sodium sesquicarbonate for SO{sub 2} removal. The proof of concept demonstration was conducted on the large combustor at the Riley Stoker Research Facility in Worcester, MA. When economically compared to conventional limestone slurry scrubbing on a 300 MW plant, the dry injection process shows lower capital cost but higher operating cost. Hydrated lime injection can be less costly than limestone scrubbing when two or more of the following conditions exist: plant is small (less than 100MW); yearly operating hours are small (less than 3000); and the remaining plant lifetime is small (less than 10 years).

  1. Water soluble graphene as electrolyte additive in magnesium-air battery system

    NASA Astrophysics Data System (ADS)

    Mayilvel Dinesh, M.; Saminathan, K.; Selvam, M.; Srither, S. R.; Rajendran, V.; Kaler, Karan V. I. S.

    2015-02-01

    Magnesium-air (Mg-air) batteries are an important energy source used to power electronic equipment and automobiles. Metal-air batteries give more energy density due to surplus air involved in reduction reaction at air cathode. In this study, the scope of improvements in the efficiency of Metal-air batteries is investigated through addition of water soluble graphene (WSG) as inhibitor in NaCl electrolyte. The discharge performance, corrosion behaviour and electrochemical impedance are studied for (i) the conventional Mg-air battery using 3.5% NaCl and (ii) Mg-air battery with WSG-based 3.5% NaCl electrolyte. X-ray diffraction analysis for WSG is carried out and it shows the crystalline nature of WSG by an intense sharp peak at 26.3°. Scanning electron microscope study is also performed and shows the flake-like structure of WSG denoted by thin layers of carbon. The immersion of WSG in 3.5% NaCl electrolyte increased the current density from 13.24 to 19.33 mA cm-2. Meanwhile, the WSG-based Mg-air battery was found to hold specific discharge capacity of 1030.71 mAh g-1, which was higher than that obtained in 3.5% NaCl electrolyte (i.e., 822.85 mAh g-1). The WSG-based Mg-air battery shows good self-discharge capacity and higher electrochemical activity during discharge.

  2. Water soluble graphene as electrolyte additive in magnesium-air battery system

    NASA Astrophysics Data System (ADS)

    Saminathan, K.; Mayilvel Dinesh, M.; Selvam, M.; Srither, S. R.; Rajendran, V.; Kaler, Karan V. I. S.

    2015-02-01

    Magnesium-air (Mg-air) batteries are an important energy source used to power electronic equipment and automobiles. Metal-air batteries give more energy density due to surplus air involved in reduction reaction at air cathode. In this study, the scope of improvements in the efficiency of Metal-air batteries is investigated through addition of water soluble graphene (WSG) as inhibitor in NaCl electrolyte. The discharge performance, corrosion behaviour and electrochemical impedance are studied for (i) the conventional Mg-air battery using 3.5% NaCl and (ii) Mg-air battery with WSG-based 3.5% NaCl electrolyte. X-ray diffraction analysis for WSG is carried out and it shows the crystalline nature of WSG by an intense sharp peak at 26.3°. Scanning electron microscope study is also performed and shows the flake-like structure of WSG denoted by thin layers of carbon. The immersion of WSG in 3.5% NaCl electrolyte increased the current density from 13.24 to 19.33 mA cm-2. Meanwhile, the WSG-based Mg-air battery was found to hold specific discharge capacity of 1030.71 mAh g-1, which was higher than that obtained in 3.5% NaCl electrolyte (i.e., 822.85 mAh g-1). The WSG-based Mg-air battery shows good self-discharge capacity and higher electrochemical activity during discharge.

  3. Predicting the effects of nanoscale cerium additives in diesel fuel on regional-scale air quality.

    PubMed

    Erdakos, Garnet B; Bhave, Prakash V; Pouliot, George A; Simon, Heather; Mathur, Rohit

    2014-11-01

    Diesel vehicles are a major source of air pollutant emissions. Fuel additives containing nanoparticulate cerium (nCe) are currently being used in some diesel vehicles to improve fuel efficiency. These fuel additives also reduce fine particulate matter (PM2.5) emissions and alter the emissions of carbon monoxide (CO), nitrogen oxides (NOx), and hydrocarbon (HC) species, including several hazardous air pollutants (HAPs). To predict their net effect on regional air quality, we review the emissions literature and develop a multipollutant inventory for a hypothetical scenario in which nCe additives are used in all on-road and nonroad diesel vehicles. We apply the Community Multiscale Air Quality (CMAQ) model to a domain covering the eastern U.S. for a summer and a winter period. Model calculations suggest modest decreases of average PM2.5 concentrations and relatively larger decreases in particulate elemental carbon. The nCe additives also have an effect on 8 h maximum ozone in summer. Variable effects on HAPs are predicted. The total U.S. emissions of fine-particulate cerium are estimated to increase 25-fold and result in elevated levels of airborne cerium (up to 22 ng/m3), which might adversely impact human health and the environment. PMID:25271762

  4. Metal-air cell comprising an electrolyte with a room temperature ionic liquid and hygroscopic additive

    DOEpatents

    Friesen, Cody A.; Krishnan, Ramkumar; Tang, Toni; Wolfe, Derek

    2014-08-19

    An electrochemical cell comprising an electrolyte comprising water and a hydrophobic ionic liquid comprising positive ions and negative ions. The electrochemical cell also includes an air electrode configured to absorb and reduce oxygen. A hydrophilic or hygroscopic additive modulates the hydrophobicity of the ionic liquid to maintain a concentration of the water in the electrolyte is between 0.001 mol % and 25 mol %.

  5. 48 CFR 1352.271-72 - Additional Item Requirements (AIR)-growth work

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... Clauses 1352.271-72 Additional Item Requirements (AIR)—growth work As prescribed in 48 CFR 1371.103... fees represent the Government's best estimate for growth that may be required throughout the contract..., Painting, Boilermaking, Pipe Fitting, Engineering (Production), Sheetmetal Work, Staging/Scaffolding,...

  6. 48 CFR 1352.271-72 - Additional Item Requirements (AIR)-growth work

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... Clauses 1352.271-72 Additional Item Requirements (AIR)—growth work As prescribed in 48 CFR 1371.103... fees represent the Government's best estimate for growth that may be required throughout the contract..., Painting, Boilermaking, Pipe Fitting, Engineering (Production), Sheetmetal Work, Staging/Scaffolding,...

  7. EVALUATION OF FULL SCALE ACTIVATED SLUDGE SYSTEMS UTILIZING POWDERED ACTIVATED CARBON ADDITION WITH WET AIR REGENERATION

    EPA Science Inventory

    The addition of powdered activated carbon (PAC) to activated sludge systems is a proven method of wastewater treatment. Of eleven POTWs in the U.S. that were designed for PAC use, ten included wet air regeneration (WAR) for the destruction of secondary sludge solids and recovery ...

  8. 48 CFR 1352.271-72 - Additional Item Requirements (AIR)-growth work

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Clauses 1352.271-72 Additional Item Requirements (AIR)—growth work As prescribed in 48 CFR 1371.103... requested by the Contracting Officer, material quotes shall be provided. (3) Subcontractor estimates, individually broken out and priced along with the actual subcontractor quotes. The requirement to...

  9. Catalytic cartridge SO.sub.3 decomposer

    DOEpatents

    Galloway, Terry R.

    1982-01-01

    A catalytic cartridge surrounding a heat pipe driven by a heat source is utilized as a SO.sub.3 decomposer for thermochemical hydrogen production. The cartridge has two embodiments, a cross-flow cartridge and an axial flow cartridge. In the cross-flow cartridge, SO.sub.3 gas is flowed through a chamber and incident normally to a catalyst coated tube extending through the chamber, the catalyst coated tube surrounding the heat pipe. In the axial-flow cartridge, SO.sub.3 gas is flowed through the annular space between concentric inner and outer cylindrical walls, the inner cylindrical wall being coated by a catalyst and surrounding the heat pipe. The modular cartridge decomposer provides high thermal efficiency, high conversion efficiency, and increased safety.

  10. Catalytic cartridge SO.sub.3 decomposer

    DOEpatents

    Galloway, Terry R.

    1982-01-01

    A catalytic cartridge internally heated is utilized as a SO.sub.3 decomposer for thermochemical hydrogen production. The cartridge has two embodiments, a cross-flow cartridge and an axial flow cartridge. In the cross-flow cartridge, SO.sub.3 gas is flowed through a chamber and incident normally to a catalyst coated tube extending through the chamber, the catalyst coated tube being internally heated. In the axial-flow cartridge, SO.sub.3 gas is flowed through the annular space between concentric inner and outer cylindrical walls, the inner cylindrical wall being coated by a catalyst and being internally heated. The modular cartridge decomposer provides high thermal efficiency, high conversion efficiency, and increased safety.

  11. Catalytic cartridge SO/sub 3/ decomposer

    DOEpatents

    Galloway, T.R.

    1980-11-18

    A catalytic cartridge surrounding a heat pipe driven by a heat source is utilized as a SO/sub 3/ decomposer for thermochemical hydrogen production. The cartridge has two embodiments, a cross-flow cartridge and an axial flow cartridge. In the cross-flow cartridge, SO/sub 3/ gas is flowed through a chamber and incident normally to a catalyst coated tube extending through the chamber, the catalyst coated tube surrounding the heat pipe. In the axial-flow cartridge, SO/sub 3/ gas is flowed through the annular space between concentric inner and outer cylindrical walls, the inner cylindrical wall being coated by a catalyst and surrounding the heat pipe. The modular cartridge decomposer provides high thermal efficiency, high conversion efficiency, and increased safety. A fusion reactor may be used as the heat source.

  12. Additives

    NASA Technical Reports Server (NTRS)

    Smalheer, C. V.

    1973-01-01

    The chemistry of lubricant additives is discussed to show what the additives are chemically and what functions they perform in the lubrication of various kinds of equipment. Current theories regarding the mode of action of lubricant additives are presented. The additive groups discussed include the following: (1) detergents and dispersants, (2) corrosion inhibitors, (3) antioxidants, (4) viscosity index improvers, (5) pour point depressants, and (6) antifouling agents.

  13. Effects of air pollution on plant-insect interactions: increased susceptibility of greenhouse-grown soybeans to the Mexican bean beetle after plant exposure to SO/sub 2/

    SciTech Connect

    Hughes, P.R.; Potter, J.E.; Weinstein, L.H.

    1982-02-01

    Foliage from greenhouse-grown soybeans fumigated with 524 ..mu..g m/sup -3/ of SO/sub 2/ or from control plants held under the same conditions without fumigation was fed to Mexican bean beetle larvae and adults. The larvae developed faster and grew larger when fed on the fumigated leaves; larval mortality was consistently low and showed no apparent relationship to the type of leaves used as the food source. Adult females showed a significant feeding preference for discs cut from fumigated leaves and were more fecund when fed on the treated foliage than when fed on control leaves. A greater percentage of the females laid eggs, and the viability of the eggs was higher when the females were fed on fumigated leaves. These females produced more eggs per individual, with significant increases in both the number of eggs per mass and the number of masses per female. The longevity of egg-laying females did not differ significantly between the treatments.

  14. Effects of air pollution on plant-insect interactions: increased susceptibility of greenhouse-grown soybeans to the Mexican bean beetle after plant exposure to SO/sub 2/

    SciTech Connect

    Hughes, P.R.; Potter, J.E.; Weinstein, L.H.

    1982-02-15

    Foliage from greenhouse-grown soybeans fumigated with 524 ..mu..g.m/sup -3/ of SO/sub 2/ or from control plants held under the same conditions without fumigation was fed to Mexican bean beetle larvae and adults. The larvae developed faster and grew larger when fed on the fumigated leaves; larva mortality was consistently low and showed no apparent relationship to the type of leaves used as the food source. Adult females showed a significant feeding preference for discs cut from fumigated leaves and were more fecund when fed on the treated foliage than when fed on control leaves. A greater percentage of the females laid eggs, and the viability of the eggs was higher when the females were fed on fumigated leaves. These females produced more eggs per individual, with significant increases in both the number of eggs per mass and the number of masses per female. The longevity of egg-laying females did not differ significantly between the treatments.

  15. Effect of additives and steaming on quality of air dried noodles.

    PubMed

    Gatade, Abhijeet Arun; Sahoo, Akshaya Kumar

    2015-12-01

    Texture is the most important property for consumer acceptance in cooked noodles. The air dried noodles are known to have higher cooking loss and cooking time, to that of instant fried noodles. But the fat content of instant fried noodles is more. In the present work attempts were made to optimize the moisture content so as to obtain a smooth dough for extruded noodle preparation and develop air dried noodles of low fat content with lesser cooking loss and cooking time. To meet the objectives, the effect of various additives and steaming treatment on cooking quality, sensory attributes, textural properties and microstructure of noodles were studied. Dough prepared by addition of 40 ml water to 100 g flour resulted into formation of a soft dough, leading to production of noodles of improved surface smoothness and maximum yield. The use of additives (5 g oil, 0.2 g guar gum, 2 g gluten and 1 ml of 1 % kansui solution for 100 g of flour) and steaming treatment showed significant effect on noodles quality, with respect to cooking characteristics, sensory attributes and textural properties. The microstructure images justified the positive correlation between the effects of ingredients with steaming and quality parameters of noodles. Air dried noodles with reduced cooking loss (~50 % reduction) with marginal reduction in cooking time was developed, which were having similar characteristics to that of instant fried noodles. Compared to the instant fried noodle, the prepared air dried noodle was having substantially reduced fat content (~70 % reduction). Thus the present study will be useful for guiding extrusion processes for production of air dried noodles having less cooking time and low fat content. PMID:26604421

  16. 76 FR 14812 - Additional Air Quality Designations for the 2006 24-Hour Fine Particle National Ambient Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-18

    ... Particle National Ambient Air Quality Standards, 110(k)(6) Correction and Technical Correction Related to... the Annual Fine Particles National Ambient Air Quality Standards Correction In rule document...

  17. SO{sub 2} compliance Cumberland Fossil Plant. Final environmental assessment

    SciTech Connect

    Not Available

    1991-08-01

    The Clean Air Act Amendments (CAAA) of 1990 require a national reduction in SO{sub 2} emissions to control acid rain. This environmental assessment (EA) describes alternative considered (and the associated environmental consequences) for complying with SO{sub 2} reduction requirements of the amendments at Tennessee Valley Authority`s (TVA) Cumberland Fossil Plant (CUF). TVA proposes to reduce SO{sub 2} emissions at CUF to 1.2 lb/10{sub 6} Btu or less as part of its compliance with the CAAA requirements. The two most viable options to achieve this reduction are a switch to western low- sulfur coal and the installation of flue gas desulfurization (FGD), also called scrubbers.

  18. Flux of SO/sub 2/ into leaf cells and cellular acidification by SO/sub 2/

    SciTech Connect

    Pfanz, H.; Martinoia, E.; Lange, O.L.; Heber, U.

    1987-12-01

    A comparison of fluxes of SO/sub 2/ from the atmosphere into leaves with fluxes across biomembranes revealed that, apart from the cuticle, the main barrier to SO/sub 2/ entry into leaves are the stomates. SO/sub 2/ fluxes into leaves can be calculated with an accuracy sufficient for many purposes on the assumption that the intracellular SO/sub 2/ concentration is zero. SO/sub 2/ entering green leaf cells is trapped in the cytoplasm. In the light, the products formed in its reaction with water are processed particularly in the chloroplasts. Flux of SO/sub 2/ to the acidic central vacuole of leaf cells is insignificant. Intracellular acidification of barley mesophyll protoplasts by SO/sub 2/ was measured by the uptake of /sup 14/C-labeled 5,5-dimethyl-oxazolidine-2,4-dione. The measured acidification was similar to the acidification calculated from known buffer capacities and the rate of SO/sub 2/ influx when the H/sup +//SO/sub 2/ ratio was assumed to be 2. A comparison of photosynthesis inhibition by SO/sub 2/ with calculated acidification revealed different mechanisms of inhibition at low and at high concentrations of SO/sub 2/. At very low concentrations, inhibition by SO/sub 2/ was even smaller than expected from calculated acidification. The data suggest that, if acidification cannot be compensated by pH-stabilizing cellular mechanisms, it is a main factor of SO/sub 2/ toxicity at low SO/sub 2/ levels. At high levels of SO/sub 2/, anion toxicity and/or radical formation during oxidation of SO/sub 2/ to sulfate may play a large role in inhibition.

  19. Novel electrochemical behavior of zinc anodes in zinc/air batteries in the presence of additives

    NASA Astrophysics Data System (ADS)

    Lee, Chang Woo; Sathiyanarayanan, K.; Eom, Seung Wook; Kim, Hyun Soo; Yun, Mun Soo

    In our continued efforts to find an electrically rechargeable zn/air secondary battery, we report the unique behavior of a zinc oxide anode in the presence of additives such as phosphoric acid, tartaric acid, succinic acid and citric acid. These additives were added to the electrolyte, which is an 8.5 M KOH solution containing 25 g of ZnO and 3000 ppm of polyethylene glycol in 1 l of water. In zn/air systems there are two main problems namely the hydrogen overpotential and dendrite formation during recharging. Investigations have studied in detail both of the problems in order to overcome them. The results obtained in presence of additives are compared with the behavior of the electrolyte 8.5 M KOH in the absence of additives. It has been concluded that the hydrogen overpotential is raised enormously while dendrite formation is reduced to some extent. Out of the four acids studied, the order of increase in hydrogen overpotential is: tartaric acid > succinic acid > phosphoric acid > citric acid. The prevention of dendrite formation follows the order: citric acid > succinic acid > tartaric acid > phosphoric acid.

  20. High SO{sub 2} removal efficiency testing: PSI Energy`s Gibson Station High SO{sub 2} Removal Efficiency Test Program

    SciTech Connect

    1996-05-20

    A program was conducted at PSI Energy`s Gibson Generating Station to evaluate options for achieving high sulfur dioxide (SO{sub 2}) removal efficiency with the Unit 5 wet limestone flue gas desulfurization (FGD) system. This program was one of six conducted by the U.S. Department of Energy to evaluate low-capital-cost upgrades to existing FGD systems as a means for utilities to comply with the requirements of the 1990 Clean Air Act Amendments (CAAA). The Gibson FGD system employs four absorber modules of the Kellogg/Weir horizontal gas flow design and uses limestone reagent with two additives. Dolomitic lime is added to introduce magnesium to increase liquid-phase alkalinity, and sulfur is added to inhibit sulfite oxidation. The high-efficiency options tested involved using sodium formate or dibasic acid (DBA) as a performance additive, increasing the absorber liquid-to-gas ratio (L/G), and/or increasing the limestone reagent stoichiometry. The unit changed coal sources during the test program. However, the Electric Power Research Institute`s (EPRI) FGD PRocess Integration and Simulation Model (FGDPRISM) was calibrated to the system and used to compare options on a consistent basis. An economic analysis was then done to determine the cost-effectiveness of each high-efficiency option. The results from this program are summarized below.

  1. NO{sub 2} removal by hydrated lime with SO{sub 2} present

    SciTech Connect

    Nelli, C.H.; Rochelle, G.T.

    1995-06-01

    At conditions typical of a bag filter in a coal fired flue gas, nitrogen dioxide (NO{sub 2}) reacted readily with surface water and sulfite ion (SO{sub 3}{sup =}) on hydrated lime. The adsorption of water and the hydrolysis of SO{sub 2} on hydrated lime provided sufficient water and sulfite to react with NO{sub 2}. The presence of oxygen in the synthesized flue gas reduced NO{sub 2} removal via sulfite oxidation on the hydrated lime surface. In addition, the presence of NO{sub 2} in the system improved total SO{sub 2} removal. A mathematical model developed to predict rates of NO{sub 2} removal by the NO{sub 2}-water and NO{sub 2}-sulfite reactions successfully compared experimental and predicted rates. These results are relevant to technology for removal of NO{sub x} by addition of methanol to dry scrubbing systems for flue gas desulfurization.

  2. Effects of humidity and temperature on the conversion of SO/sub 2/ to particulate sulfate and sulfite. Final report

    SciTech Connect

    Freiberg, J.E.

    1983-11-01

    Effects of humidity and temperature on SO/sub 2/ conversion to particulate sulfate and sulfite in relation to heterogeneous conversion in droplets and on particle surfaces; homogeneous conversion in the gas phase; and gas-to-particle conversion are discussed. Theoretical quantitative expressions for some effects are derived and order-of-magnitude calculations are given. Detailed conclusions and comparisons regarding the effects of temperature and humidity on specific oxidation paths. Major conclusions documented are: rates of SO/sub 2/ to SO/sub 4//sup =/ converison in aqueous droplets are generally negatively correlated with temperature and positively correlated with relative humidity (particularly at high relative humidity); the rates of SO/sub 2/ to SO/sub 4//sup =/ conversion on reactive surfaces can be either positively correlated with relative humidity or unaffected by relative humidity, and can have a negative, a positive, or a zero correlation with temperture; the homogeneous photooxidation is considerably less sensitive to temperature than is the heterogeneous conversion. (The photooxidation of SO/sub 2/ is expected to be positively correlated with temperature, but the correlation will be weaker in clean air than in polluted air, the positive dependence of SO/sub 2/ photooxidation on humidity will be weaker in polluted air containing NMHC than in clean air); the specific conversion paths have rates with highly different sensitivities to relative humidity and temperature. Thus, a given conversion path can become more or less significant relative to other paths as relative humidity and temperature vary. This suggests that temperature and relative humidity variations can be major causes of the temporal and spatial variations in the rate and yield of conversion and in the type of sulfate produced, which in turn determine the extent of adverse environmental effects. 228 references, 1 figure, 28 tables.

  3. Additive-free harvesting of oleaginous phagotrophic microalga by oil and air flotation.

    PubMed

    Hosseini, Majid; Starvaggi, Haley A; Ju, Lu-Kwang

    2016-07-01

    A unique oleaginous phagotrophic microalga Ochromonas danica is poised for effective lipid production from waste. Cell harvesting and dewatering are major costs in making algae-based products. In this work an effective additive-free harvesting method was developed, taking advantage of O. danica's comparatively more hydrophobic surface and larger size. The algal cells' partitioning to oil/water interface was evaluated. Recovery by flotation with waste cooking oil was optimized using an L-9 Taguchi orthogonal-array design. Further, additive-free cell collection and concentrating by air flotation was studied for the effects of both physical factors (column dimension, air-stone pore size, sample-to-column volume ratio) and culture properties (pH, culture growth stage, cell concentration, and pure versus impure cultures). The optimized process consistently achieved >90 % recovery in a single stage. 98+ % recovery could be achieved when starting concentrations were >10(8) cells/ml, or potentially using a two- or multi-stage process for diluter cultures. PMID:27025209

  4. Direct observation of reversible and irreversible stomatal responses of attached sunflower leaves to SO/sub 2/

    SciTech Connect

    Omasa, K.; Hashimoto, Y.; Kramer, P.J.; Strain, B.R.; Aiga, I.; Kondo, J.

    1985-09-01

    The effects of SO/sub 2/ on stomatal aperture of attached sunflower leaves were observed with a remote-control light microscope system that permitted continuous observation of stomatal responses over periods of several hours. The relationship between actual stomatal aperture and stomatal conductance, measured with a porometer, also was examined on leaves before and after exposure to SO/sub 2/. A distinction between uninjured and injured regions was clearly visible on leaves after exposure to 1.5 microliters per liter SO/sub 2/ for less than an hour. During the exposure, the mean value of apertures for many stomata, which indicates stomatal conductance and transpiration rate, tended to decrease simultaneously in the uninjured and injured regions. There was a good correlation between pore width and stomatal conductance measured with a porometer before exposure to SO/sub 2/. This correlation continued in leaves exposed to SO/sub 2/ until visible, irreversible injury occurred, but then it disappeared. The results of these experiments indicate the necessity of continuous observation of individual stomata under the microscope to understand the effects of air pollutants such as SO/sub 2/ on stomatal behavior.

  5. Influence of propane additives on the detonation characteristics of H2-air mixtures

    NASA Astrophysics Data System (ADS)

    Cheng, Guanbing; Bauer, Pascal; Zitoun, Ratiba

    2014-03-01

    Hydrogen is more and more considered as a potential fuel for propulsion applications. However, due to its low ignition energy and wide flammability limits, H2-air mixtures raise a concern in terms of safety. This aspect can be partly solved by adding an alkane to these mixtures, which plays the role of an inhibitor. The present paper provides data on such binary fuel-air mixtures where various amounts of propane are added to hydrogen. The behavior of the corresponding mixtures, in terms of detonation characteristics and other fundamental properties, such as the cell size of the detonation front and induction delay, are presented and discussed for a series of equivalence ratios and propane addition. The experimental detonation velocity is in good agreement with calculated theoretical Chapman-Jouguet values. Based on soot tracks records, the cell size λ is measured, whereas the induction length L i is derived from data using a GRI-Mech kinetic mechanism. These data allow providing a value of the coefficient K = λ/L i .

  6. Turbulent Drag Reduction with Surfactant Additives — Basic Research and Application to an Air Conditioning System

    NASA Astrophysics Data System (ADS)

    Kawaguchi, Y.; Li, F. C.; Yu, B.; Wei, J. J.

    It is well known that a small amount of chemicals such as water-soluble polymers or surfactants dramatically suppresses turbulence when they are added to liquid flow at large Reynolds number. In the last two decades, the application of surfactants to heat transportation systems such as district heating and cooling systems has attracted much interest among researchers. It has been revealed that 70% of the pumping power used to drive hot water in primary pipelines or district heating systems was saved by adding only a few hundred ppm of surfactant into the circulating water. The technological achievement requires a new design strategy for pipeline networks and heat exchangers to handle the drag reducing liquid flow. In the case of a Newtonian fluid such as water or air, the knowledge for designing fluid systems has been accumulated and the accuracy of numerical prediction is sufficient. On the other hand, the design system for surfactant solutions is not mature because drag-reducing flow phenomena are much more complicated than for Newtonian flow, for example, the friction factor for a surfactant solution depends not only on Reynolds number but also pipe diameter. In order to provide a design strategy for heat transportation systems using surfactant additives, we are now carrying out both experimental and numerical studies for surfactant solutions. In this lecture, experimental and numerical studies on the turbulence structure in drag reducing flow will be introduced. The result of an application study relating to the air conditioning system will be also shown.

  7. Coal sulfur-premium models for SO{sub 2} allowance valuation

    SciTech Connect

    Henry, J.B. II; Radulski, D.R.; Ellingson, E.G.; Engels, J.P.

    1995-12-31

    Clean Air Capital Markets, an investment bank structuring SO{sub 2} Allowance transactions, has designed two allowance value models. The first forecasts an equilibrium allowance value based on coal supply and demand. The second estimates the sulfur premium of all reported coal deliveries to utilities. Both models demonstrate that the fundamental allowance value is approximately double current spot market prices for small volumes of off-system allowances.

  8. Effect of pressure on preparation of SO{sub 2} sorbent from leonardite and on SO{sub 2} adsorption by limestone and dolomite as determined from pressure thermogravimetric analysis

    SciTech Connect

    Timpe, R.C.; Kulas, R.W.; Young, B.C.

    1996-12-31

    Control of SO{sub 2} with limestone or dolomite is state-of-the-art at the present time, but activated carbon in the form of low-rank coal char also has some promise. A process for production of the sorbent includes selection of temperature regime, pressure, activation gas, residence time, and additive. The effect of pressure on the behavior of sorbent during SO{sub 2} removal from flue gas or during production of sorbent carbon is the parameter least found in the literature. Pressure thermogravimetric analysis (pTGA) provides a simple means of studying this effect. In this study, a fully calcined and a partially calcined dolomite and limestone were tested for SO{sub 2} sorbent characteristics under pTGA at 840{degrees}C at 160 psig. The stories were characterized by capacity and rate of sorption of SO{sub 2}. A leonardite was carbonized at 480{degrees}C and activated at 800{degrees}C under nitrogen at ambient, 150, 300, and 450 psig. Each char was then exposed to a flowing gas mixture containing argon and SO{sub 2}. The char produced at lower pressures adsorbed more SO{sub 2} than those produced at successively higher pressures as determined by TGA and confirmed by American Society for Testing and Materials (ASTM) total sulfur measurements.

  9. 76 FR 6056 - Additional Air Quality Designations for the 2006 24-Hour Fine Particle National Ambient Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-03

    ... Protection Agency FR Federal Register NAAQS National Ambient Air Quality Standards NTTAA National Technology... (74 FR 58688), EPA deferred designations for three areas to evaluate further the reason for their high... November 13, 2009 notice (74 FR 58688), we also announced that our review of 2006-2008 monitoring data...

  10. 77 FR 65310 - Additional Air Quality Designations for the 2006 24-Hour Fine Particle National Ambient Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-26

    ... the 2006 24-hour Fine Particle (PM 2.5 ) National Ambient Air Quality Standards,'' 74 FR 58688... Federal Regulations DC District of Columbia EO Executive Order EPA Environmental Protection Agency FR... EPA finalized designations for the 2006 24-hour PM 2.5 NAAQS (74 FR 58688, November 13, 2009), the...

  11. Suppression of methane/air explosion by ultrafine water mist containing sodium chloride additive.

    PubMed

    Cao, Xingyan; Ren, Jingjie; Zhou, Yihui; Wang, Qiuju; Gao, Xuliang; Bi, Mingshu

    2015-03-21

    The suppression effect of ultrafine mists on methane/air explosions with methane concentrations of 6.5%, 8%, 9.5%, 11%, and 13.5% were experimentally studied in a closed visual vessel. Ultrafine water/NaCl solution mist as well as pure water mist was adopted and the droplet sizes of mists were measured by phase doppler particle analyzer (PDPA). A high speed camera was used to record the flame evolution processes. In contrast to pure water mist, the flame propagation speed, the maximum explosion overpressure (ΔP(max)), and the maximum pressure rising rate ((dP/dt)max) decreased significantly, with the "tulip" flame disappearing and the flame getting brighter. The results show that the suppressing effect on methane explosion by ultrafine water/NaCl solution mist is influenced by the mist amount and methane concentration. With the increase of the mist amount, the pressure, and the flame speed both descended significantly. And when the mist amount reached 74.08 g/m(3) and 37.04 g/m(3), the flames of 6.5% and 13.5% methane explosions can be absolutely suppressed, respectively. All of results indicate that addition of NaCl can improve the suppression effect of ultrafine pure water mist on the methane explosions, and the suppression effect is considered due to the combination effect of physical and chemical inhibitions. PMID:25528229

  12. Removal of SO{sub 2} from simulated flue gases using non-thermal plasma-based microgap discharge

    SciTech Connect

    Zhitao Zhang; Mindong Bai; Mindi Bai; Xiyao Bai; Qiaoyuan Pan

    2006-06-15

    The removal of sulfur dioxide (SO{sub 2}) from simulated flue gases streams (N{sub 2}/O{sub 2}/H{sub 2}O/SO{sub 2}) was experimentally investigated using microgap discharge. In the experiment, the thinner dielectric layers of aluminum oxide (Al{sub 2}O{sub 3}) were used to form the microgap discharge. With this physical method, a high concentration of hydroxyl (OH) radicals were produced using the ionization of O{sub 2} and H{sub 2}O to further the conversion of SO{sub 2} into sulfuric acid (H{sub 2}SO{sub 4}) at 120{sup o}C in the absence of any catalysts and absorbents, which were captured with the electrostatic precipitator (ESP). As a result, the increase of discharge power and concentrations of O{sub 2} and H{sub 2}O increased the production of OH radicals resulting in enhanced removal of SO{sub 2} from gas streams. With the test and analysis, a number of H{sub 2}SO{sub 4} droplets were produced in experiment. Therefore, a new method for removal of SO{sub 2} in semidry method without ammonia (NH{sub 3}) additive was found. 24 refs., 8 figs., 2 tabs.

  13. Predicting the Effects of Nano-Scale Cerium Additives in Diesel Fuel on Regional-Scale Air Quality

    EPA Science Inventory

    Diesel vehicles are a major source of air pollutant emissions. Fuel additives containing nanoparticulate cerium (nCe) are currently being used in some diesel vehicles to improve fuel efficiency. These fuel additives also reduce fine particulate matter (PM2.5) emissio...

  14. 40 CFR 49.5 - Tribal requests for additional Clean Air Act provisions for which it is not appropriate to treat...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... TRIBAL CLEAN AIR ACT AUTHORITY Tribal Authority § 49.5 Tribal requests for additional Clean Air Act... request that the Administrator specify additional provisions of the Clean Air Act for which it would be... Air Act provisions for which it is not appropriate to treat tribes in the same manner as States....

  15. Complexation of n SO{sub 2} molecules (n = 1, 2, 3) with formaldehyde and thioformaldehyde

    SciTech Connect

    Azofra, Luis Miguel; Scheiner, Steve

    2014-01-21

    Ab initio and density functional theory calculations are used to examine complexes formed between H{sub 2}CO and H{sub 2}CS with 1, 2, and 3 molecules of SO{sub 2}. The nature of the interactions is probed by a variety of means, including electrostatic potentials, natural bond orbital, atoms in molecules, energy decomposition, and electron density redistribution maps. The dimers are relatively strongly bound, with interaction energies exceeding 5 kcal/mol. The structures are cyclic, containing both a O/S⋯S chalcogen bond and a CH⋯O H-bond. Addition of a second SO{sub 2} molecule leads to a variety of heterotrimer structures, most of which resemble the original dimer, where the second SO{sub 2} molecule engages in a chalcogen bond with the first SO{sub 2}, and a C⋯O attraction with the H{sub 2}CX. Some cooperativity is apparent in the trimers and tetramers, with an attractive three-body interaction energy and shortened intermolecular distances.

  16. SO{sub 3}'s impacts on plant O & M: part II

    SciTech Connect

    Moser, R.E.

    2007-02-15

    Part 1 of this three-part series (Power, October 2006, Coal Abstracts entry Jan 2007 00224) explored the negative impacts of sulfur trioxide (SO{sub 3}) on the operation and maintenance of back-end plant equipment. This article lists and quantifies the likely and potential benefits of limiting the concentration of SO{sub 3} in flue gas to 3 ppm at the entrance to the air heater. Benefits include: reduced acid dew point and back-end corrosion; reduced heat rate and fuel costs; reduced or eliminated ABS fouling of air heaters; reduced fireside corrosion; enabling the use of lower-oxidation catalysts; higher mercury removal efficiency; and lower temperature SCR operation. Part III, to appear in April 2007, will describe the characteristics of an optimal SO{sub 3} removal technology and present the technical details and operating experience of one patented process that has worked successfully at a half-dozen plants for up to three years. 1 ref., 5 figs.

  17. Combined SO{sub 2}/NO{sub x} reduction technology

    SciTech Connect

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

    1992-09-01

    Enactment of the Clean Air Act Amendments and passage of state legislation leading to more stringent nitrogen oxides (NO{sub x}) regulations have fueled research and development efforts on technologies for the combined control of sulfur dioxide (SO{sub 2}) and NO{sub x}. The integrated removal of both SO{sub 2} and NO{sub x}, in a single system can offer significant advantages over the use of several separate processes, including such factors as reduced system complexity, better operability, and lower costs. This paper reviews the status of a number of integrated flue-gas-cleanup (FGC) systems that have reached a significant stage of development, focusing on post-combustion processes that have been tested or are ready for testing at the pilot scale or larger. A brief process description, a summary of the development status and performance achieved to date, pending commercialization issues, and process economics (when available) are given for each technology.

  18. Is it time to rethink SO{sub 2} control technology selection?

    SciTech Connect

    Dickerman, J.; Swell, M.

    2007-11-15

    The article traces the history of flue gas desulfurization (FGD) systems in power plants in the USA following the 1990 Clean Air Act which divided boilers into Phase I (larger SO{sub 2} emitters) and Phase II units. The Clean Air Interstate Rule (CAIR) will soon require emission control on smaller boilers burning low and medium-sulfur coal. Today the systems of choice are dry FGD systems for low sulfur coals and greater than wet LSFO. (limestone forced oxidation systems) for coal with sulfur content about 2%. Demand for wet FGD coupled with tighter regulations has led to significant cost increases in LSFO. technology. 4 refs., 2 figs.

  19. Numerical analysis of volcanic SO{sub 2} plume transport

    SciTech Connect

    Uno, Itsushi

    1996-12-31

    Mt. Sakurajima volcano (1060m) located southern part of Kyushu island, Japan, emitted a huge amount of volcanic gas (e.g., 1000-2000 SO{sub 2}-ton/day) and has a strong impact in the environmental SO{sub 2} concentration. This volcanic SO{sub 2} plume transport process over the Kyushu island was simulated by a random walk model based on the wind and turbulence fields simulated by a mesoscale numerical model using four-dimensional data assimilation (FDDA). Continuous four days of numerical simulation was the period covering from May 7 to May 10, 1987. Grided global analysis by ECMWF and the special pilot-balloon observation data were used in the FDDA. Mesoscale numerical model with FDDA simulated well the general wind fields during the passage of high pressure system, and the complicated local wind circulation within the planetary boundary layer (PBL). Simulated surface wind variation was quantitatively compared with the observation data, and showed the good agreements. Numerical results of plume transport process were compared with SO{sub 2} surface and 3-D airborne measurements. It was revealed that simulated three-dimensional plume behavior explained well the observed SO{sub 2} variation, and the day-time development of PBL played an important role for the transport of the volcanic SO{sub 2} aloft to the surface level. Transformation rate from SO{sub 2} to sulfate was also determined from the trajectory by the random walk calculation.

  20. 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.

  1. SO{sub 2} effects on CO oxidation in a CO{sub 2} atmosphere, characteristic of oxy-fuel conditions

    SciTech Connect

    Gimenez-Lopez, J.; Martinez, M.; Millera, A.; Bilbao, R.; Alzueta, M.U.

    2011-01-15

    SO{sub 2} is an important pollutant formed during many combustion processes which may affect the oxidation of the fuel. The current work focuses on the evaluation of the effect of the presence of SO{sub 2} on CO oxidation in a CO{sub 2} atmosphere, found in oxy-fuel combustion, in comparison to a N{sub 2} dilution characteristic of air combustion. A flow reactor experimental and kinetic modeling study of the gas-phase interaction of SO{sub 2} with the radical pool during CO oxidation under CO{sub 2} and N{sub 2} diluted conditions has been carried out for different stoichiometries in the 800-1800 K temperature range. The presence of SO{sub 2} is seen to inhibit the oxidation of CO in both atmospheres for all the stoichiometries studied, although the inhibition is significantly higher as the stoichiometry becomes more reducing. The inhibiting effect of SO{sub 2} in the CO{sub 2} atmosphere is caused by similar radical recombination mechanisms than those occurring with N{sub 2}. Under fuel-rich conditions, the inhibition is governed by the SO{sub 2}/HOSO inter-conversion and is less pronounced as the CO{sub 2} concentration increases. However, as the conditions are more fuel-lean, the SO{sub 2} inhibiting effect is comparable in both atmospheres due to the higher importance of the SO{sub 2} + O recombination. As the SO{sub 2} concentration increases, its interaction with the radical pool is enhanced and the inhibition of CO oxidation is higher. An updated kinetic mechanism is used for calculations and provides a very good description of the experimental results for all the operating conditions analyzed. (author)

  2. Air

    MedlinePlus

    ... do to protect yourself from dirty air . Indoor air pollution and outdoor air pollution Air can be polluted indoors and it can ... this chart to see what things cause indoor air pollution and what things cause outdoor air pollution! Indoor ...

  3. Spray droplet sizes with additives discharged from an air-assisted variable-rate nozzle

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding droplet size distributions is essential to achieve constant spray quality for real-time variable-rate sprayers that synchronize spray outputs with canopy structures. Droplet sizes were measured for a custom-designed, air-assisted, five-port nozzle coupled with a pulse width modulated (...

  4. Responses of soybean leaf metabolism to SO/sub 2/ fumigation. [Glycine max

    SciTech Connect

    Macomber, M.A.; Hess, J.L.; Sheng, W.; Chevone, B.I.

    1987-04-01

    Response of glutathione, ascorbate, and H/sub 2/O/sub 2/ concentrations in leaves of higher plants exposed to low levels of O/sub 3/ and SO/sub 2/ was quantified. Glycine max L cv Dare and Williams were grown in a charcoal-filtered air glass house. Exposures to 0.7 ppm SO/sub 2/ for 2 h resulted in minimal effects on photosynthesis, however, at 2 ppm a reduction in photosynthesis was accompanied by a 75% decrease in glutamate and aspartate. Sulfate increased 50% and total free thiol (Ellman-positive material) increased 300%. No significant changes were observed in the total concentration of glutathione or cysteine. No changes were detected in the oxidized to reduced glutathione ratio, and ascorbate and H/sub 2/O/sub 2/ content remained constant. In contrast, fumigations with 0.8 ppm ozone for 2 h resulted in approximately a 30% increase in leaf hydrogen peroxide. No obvious change occurred in ascorbate or glutathione metabolism. Altered pseudocyclic electron flow to H/sub 2/O/sub 2/ may not occur in soybean leaf following exposure to SO/sub 2/.

  5. Advanced in-duct sorbent injection for SO{sub 2} control. Final technical report

    SciTech Connect

    Stouffer, M.R.; Withium, J.A.; Rosenhoover, W.A.; Maskew, J.T.

    1994-12-01

    The objective of this research project was to develop a second generation duct sorbent injection technology as a cost-effective compliance option for the 1990 Clean Air Act Amendments. Research and development work was focused on the Advanced Coolside process, which showed the potential for exceeding the original performance targets of 90% SO{sub 2} removal and 60% sorbent utilization. Process development was conducted in a 1000 acfm pilot plant. The pilot plant testing showed that the Advanced Coolside process can achieve 90% SO{sub 2} removal at sorbent utilizations up to 75%. The testing also showed that the process has the potential to achieve very high removal efficiency (90 to >99%). By conducting conceptual process design and economic evaluations periodically during the project, development work was focused on process design improvements which substantially lowered process capital and operating costs, A final process economic study projects capital costs less than one half of those for limestone forced oxidation wet FGD. Projected total SO{sub 2} control cost is about 25% lower than wet FGD for a 260 MWe plant burning a 2.5% sulfur coal. A waste management study showed the acceptability of landfill disposal; it also identified a potential avenue for by-product utilization which should be further investigated. Based on the pilot plant performance and on the above economic projections, future work to scale up the Advanced Coolside process is recommended.

  6. 40 CFR 49.5 - Tribal requests for additional Clean Air Act provisions for which it is not appropriate to treat...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... additional Clean Air Act provisions for which it is not appropriate to treat tribes in the same manner as States. Any tribe may request that the Administrator specify additional provisions of the Clean Air Act... Air Act provisions for which it is not appropriate to treat tribes in the same manner as States....

  7. 40 CFR 49.5 - Tribal requests for additional Clean Air Act provisions for which it is not appropriate to treat...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... additional Clean Air Act provisions for which it is not appropriate to treat tribes in the same manner as States. Any tribe may request that the Administrator specify additional provisions of the Clean Air Act... Air Act provisions for which it is not appropriate to treat tribes in the same manner as States....

  8. 40 CFR 49.5 - Tribal requests for additional Clean Air Act provisions for which it is not appropriate to treat...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... additional Clean Air Act provisions for which it is not appropriate to treat tribes in the same manner as States. Any tribe may request that the Administrator specify additional provisions of the Clean Air Act... Air Act provisions for which it is not appropriate to treat tribes in the same manner as States....

  9. 40 CFR 49.5 - Tribal requests for additional Clean Air Act provisions for which it is not appropriate to treat...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... additional Clean Air Act provisions for which it is not appropriate to treat tribes in the same manner as States. Any tribe may request that the Administrator specify additional provisions of the Clean Air Act... Air Act provisions for which it is not appropriate to treat tribes in the same manner as States....

  10. Effect of plasma suppression additives on electrodynamic characteristics of the torch discharge burning in the air

    NASA Astrophysics Data System (ADS)

    Vidyaev, D.; Lutsenko, Yu; Boretsky, E.

    2016-06-01

    The paper shows the results of measurements of wave number of electromagnetic wave, which supports burning of high-frequency torch discharge in the mixture of air with water vapor and carbon dioxide. The nonmonotonic dependence of attenuation factor of electromagnetic waves is set on a concentration of water vapor. It is shown that the attenuation degree of electromagnetic field in the plasma with water vapor significantly exceeds the attenuation degree of electromagnetic field in the plasma with carbon dioxide.

  11. Historical analysis of SO{sub 2} pollution control policies in China

    SciTech Connect

    Gao, C.L.; Yin, H.Q.; Ai, N.S.; Huang, Z.W.

    2009-03-15

    Coal is not only an important energy source in China but also a major source of air pollution. Because of this, China's national sulfur dioxide (SO{sub 2}) emissions have been the highest in the world for many years, and since the 1990s, the territory of China's south and southwest has become the third largest acid-rain-prone region in the world. In order to control SO{sub 2} emissions, the Chinese government has formulated and promulgated a series of policies and regulations, but it faces great difficulties in putting them into practice. In this retrospective look at the history of SO{sub 2} control in China, we found that Chinese SO{sub 2} control policies have become increasingly strict and rigid. We also found that the environmental policies and regulations are more effective when central officials consistently give environmental protection top priority. Achieving China's environmental goals, however, has been made difficult by China's economic growth. Part of this is due to the practice of environmental protection appearing in the form of an ideological 'campaign' or 'storm' that lacks effective economic measures. More recently, better enforcement of environmental laws and regulations has been achieved by adding environmental quality to the performance assessment metrics for leaders at all levels. To continue making advances, China needs to reinforce the economic and environmental assessments for pollution control projects and work harder to integrate economic measures into environmental protection. Nonetheless, China has a long way to go before economic growth and environmental protection are balanced.

  12. Elastic Properties and Structural Studies on Boro-Vanadate Glasses Containing Sulphate (SO{sub 4}{sup 2-}) Ions

    SciTech Connect

    Reddy, M. Sudhakar; Gowda, V. C. Veeranna; Reddy, C. Narayana

    2011-12-12

    Elastic properties of xLi{sub 2}SO{sub 4}-16 Li{sub 2}O-(84-x) [0.7 B{sub 2}O{sub 3}-0.3 V{sub 2}O{sub 5}] where (5{<=}x{>=}30) glasses have been prepared by melt quenching method and structural investigations were carried out using ultrasonic pulse echo overlap technique at a frequency of 10 MHz and at 300 K. The molar volume increases and the density decreases with the increase of Li{sub 2}SO{sub 4} concentration due to the incorporation of SO{sub 4}{sup 2-} ions into the modified macromolecular network. The addition of Li{sub 2}SO{sub 4} content leads to loose packing structure which is attributed to volume increasing effect and the reduction in the vibrations of borate and vanadate lattices. Increase in Li{sub 2}{sup SO}{sub 4} results in decreasing cross link density which in turn decreases elastic moduli. The results are discussed in view of its network structure. The structural groups [VOO{sub 3/2}]{sup 0} and [BO{sub 3/2}]{sup 0} modify preferentially. This preference in modification is decided by the electronegativity ({chi}) of the structural groups.

  13. Effect of pressure on preparation of SO{sub 2} sorbent from leonardite and on SO{sub 2} adsorption by limestone and dolomite as determined from pressure thermogravimetric analysis

    SciTech Connect

    Timpe, R.C.; Kulas, R.W.; Young, B.C.

    1996-10-01

    Control of SO{sub 2} with activated carbon in the form of low-rank coal char has some promise. A process for production of the sorbent includes selection of temperature regime, pressure, activation gas, residence time, and additive. The effect of pressure on the production of sorbent carbon is the parameter least found in the literature. Pressure thermogravimetric analysis (pTGA) provides a simple means of determining this effect. In this study, a leonardite was carbonized at 480{degrees}C and activated at 800{degrees}C under nitrogen at ambient, 150, 300, and 450 psig. Each char was then exposed to a flowing gas mixture containing argon and SO{sub 2}. The char produced at lower pressures adsorbed more SO{sub 2} than those produced at successively higher pressures as determined by TGA and confirmed by ASTM total sulfur measurements.

  14. Simultaneous removal of SO{sub 2}, NOx, and Hg from coal flue gas using a NaClO{sub 2}-enhanced wet scrubber

    SciTech Connect

    Hutson, N.D.; Krzyzynska, R.; Srivastava, R.K.

    2008-08-15

    A bench-scale study was conducted on the simultaneous removal Of SO{sub 2}, NOx, and mercury (both Hg{sup 0} and Hg{sup 2+}) from a simulated coal flue gas using a wet calcium carbonate scrubber. The multipollutant capacity of the scrubber was enhanced with the addition of the oxidizing salt, sodium chlorite. The results showed a maximum scrubbing of 100% for SO{sub 2} and Hg species and near complete NO oxidation with about 60% scrubbing of the resulting NOx species. The chlorite additive was less effective as an oxidant in the absence of SO{sub 2} and NO in the flue gas. Oxidation of NO and mercury were only about 50% and 80%, respectively, in the case of no SO{sub 2} in the simulated flue gas. The mercury oxidation was similarly affected by the absence of NO in the flue gas.

  15. At what cost do we reduce pollution Shadow prices of SO[sub 2] emissions

    SciTech Connect

    Swinton, J.R. )

    1998-01-01

    The US EPA's infant market for SO[sub 2] emissions has the potential for improving the cost effectiveness of reducing acid rain pollutants. If the market works as planned, over time one should see the cost of reducing additional amounts of sulfur dioxide converge across plants. The results of the study described here demonstrate that before the market opened marginal abatement costs varied wildly across plants. This work provides estimates of the shadow price of SO[sub 2] abatement using the output distance function approach for Illinois, Minnesota and Wisconsin coal-burning electric plants. The results demonstrate that the coal-burning electric plants with the highest emissions rates are also the plants with the lowest marginal abatement costs, a fact that may explain lower-than-expected prices in the new market for allowances. The data include information about plants with installed scrubber capital allowing for an investigation of the effect of scrubber capital on marginal abatement costs.

  16. On the effect of carbon monoxide addition on soot formation in a laminar ethylene/air coflow diffusion flame

    SciTech Connect

    Guo, Hongsheng; Thomson, Kevin A.; Smallwood, Gregory J.

    2009-06-15

    The effect of carbon monoxide addition on soot formation in an ethylene/air diffusion flame is investigated by experiment and detailed numerical simulation. The paper focuses on the chemical effect of carbon monoxide addition by comparing the results of carbon monoxide and nitrogen diluted flames. Both experiment and simulation show that although overall the addition of carbon monoxide monotonically reduces the formation of soot, the chemical effect promotes the formation of soot in an ethylene/air diffusion flame. The further analysis of the details of the numerical result suggests that the chemical effect of carbon monoxide addition may be caused by the modifications to the flame temperature, soot surface growth and oxidation reactions. Flame temperature increases relative to a nitrogen diluted flame, which results in a higher surface growth rate, when carbon monoxide is added. Furthermore, the addition of carbon monoxide increases the concentration of H radical owing to the intensified forward rate of the reaction CO + OH = CO{sub 2} + H and therefore increases the surface growth reaction rates. The addition of carbon monoxide also slows the oxidation rate of soot because the same reaction CO + OH = CO{sub 2} + H results in a lower concentration of OH. (author)

  17. A numerical study of the influence of ammonia addition on the auto-ignition limits of methane/air mixtures.

    PubMed

    Van den Schoor, F; Norman, F; Vandebroek, L; Verplaetsen, F; Berghmans, J

    2009-05-30

    In this study the auto-ignition limit of ammonia/methane/air mixtures is calculated based upon a perfectly stirred reactor model with convective heat transfer. The results of four different reaction mechanisms are compared with existing experimental data at an initial temperature of 723 K with ammonia concentrations of 0-20 mol.% and methane concentrations of 2.5-10 mol.%. It is found that the calculation of the auto-ignition limit pressure at constant temperature leads to larger relative deviations between calculated and experimental results than the calculation of the auto-ignition temperature at constant pressure. In addition to the calculations, a reaction path analysis is performed to explain the observed lowering of the auto-ignition limit of methane/air mixtures by ammonia addition. It is found that this decrease is caused by the formation of NO and NO(2), which enhance the oxidation of methane at low temperatures. PMID:18926632

  18. Addition of PM2.5 into the National Ambient Air Quality Standards of China and the Contribution to Air Pollution Control: The Case Study of Wuhan, China

    PubMed Central

    You, Mingqing

    2014-01-01

    PM2.5 has gradually become a major environmental problem of China with its rapid economic development, urbanization, and increasing of motor vehicles. Findings and awareness of serious PM2.5 pollution make the PM2.5 a new criterion pollutant of the Chinese National Ambient Air Quality Standard (NAAQS) revised in 2012. The 2012 NAAQS sets the PM2.5 concentrate limitation with the 24-hour average value and the annual mean value. Wuhan is quite typical among central and southern China in climate, economy, development level, and energy consumption. The data are cited from the official website of Wuhan Environmental Protection Bureau and cover the period from 1 January to 30 June 2013. The data definitely confirm the existence of serious PM2.5 pollution in Wuhan and indicate that the addition of PM2.5 as a criterion pollutant significantly brings down the attainment rate of air quality. The example of Wuhan reveals that local governments should take measures to reduce the emission of PM2.5 if it affects the attainment rate and the performance evaluation value of air quality. The main contribution of 2012 NAAQS is that it brings down the attainment rate of the air quality and forces local governmental officials to take the measures accordingly. PMID:24982994

  19. Olefin Metathesis Reaction in Water and in Air Improved by Supramolecular Additives.

    PubMed

    Tomasek, Jasmine; Seßler, Miriam; Gröger, Harald; Schatz, Jürgen

    2015-01-01

    A range of water-immiscible commercially available Grubbs-type precatalysts can be used in ring-closing olefin metathesis reaction in high yields. The synthetic transformation is possible in pure water under ambient conditions. Sulfocalixarenes can help to boost the reactivity of the metathesis reaction by catalyst activation, improved mass transfer, and solubility of reactants in the aqueous reaction media. Additionally, the use of supramolecular additives allows lower catalyst loadings, but still high activity in pure water under aerobic conditions. PMID:26506329

  20. Performance of AA5052 alloy anode in alkaline ethylene glycol electrolyte with dicarboxylic acids additives for aluminium-air batteries

    NASA Astrophysics Data System (ADS)

    Wang, DaPeng; Zhang, DaQuan; Lee, KangYong; Gao, LiXin

    2015-11-01

    Dicarboxylic acid compounds, i.e. succinic acid (SUA), adipic acid (ADA) and sebacic acid (SEA), are used as electrolyte additives in the alkaline ethylene glycol solution for AA5052 aluminium-air batteries. It shows that the addition of dicarboxylic acids lowers the hydrogen gas evolution rate of commercial AA5052 aluminium alloy anode. AA5052 aluminium alloy has wide potential window for electrochemical activity and better discharge performance in alkaline ethylene glycol solution containing dicarboxylic acid additives. ADA has the best inhibition effect for the self-corrosion of AA5052 anode among the three dicarboxylic acid additives. Fourier transform infrared spectroscopy (FT-IR) reveals that dicarboxylic acids and aluminium ions can form coordination complexes. Quantum chemical calculations shows that ADA has a smaller energy gap (ΔE, the energy difference between the lowest unoccupied orbital and the highest occupied orbital), indicating that ADA has the strongest interaction with aluminium ions.

  1. Simultaneous removal of SO{sub 2} and NO by highly reactive absorbent containing calcium hypochlorite

    SciTech Connect

    Zhao, Y.; Xu, P.Y.; Wang, L.D.

    2008-12-15

    Fly ash, industrial lime, and an additive (calcium hypochlorite )) were used to prepare a highly reactive absorbent. Simultaneous desulfurization and denitrification were carried out in a flue gas circulating fluidized bed (CFB). The effects of influencing factors on the removal efficiencies of SO{sub 2} and NO were also investigated. Removal efficiencies of 94.5% for SO{sub 2} and 65.5% for NO were obtained under the optimal experimental conditions. The component of the spent absorbent was analyzed with chemical analysis methods. The results indicated that more nitrogen than sulfur species appeared in the spent absorbent. A scanning electron microscope (SEM) and an accessory X-ray energy spectrometer (EDS) were used to observe the microproperties of the samples, including fly ash, highly reactive absorbent, and spent absorbent. The removal products of spent absorbent were analyzed using ion chromatography and chemical analysis. The simultaneous removal mechanism of SO{sub 2} and NO based on this absorbent was proposed according to the experimental results.

  2. Experimental evaluation of water mist with metal chloride additives for suppressing CH4/air cup-burner flames

    NASA Astrophysics Data System (ADS)

    Liu, Jianghong; Cong, Beihua

    2013-06-01

    In order to investigate the fire suppression effectiveness of water mist with metal chloride additives, ultrafine water mists of these salts with diameters about 10μm were introduced into CH4/air non-premixed flame in the cup burner. Results showed that these droplets hard to make itself to the flame front under the cup burner flow conditions functioned as a carrier of the vaporized solid particles or its decomposed materials. The metal chloride improved fire suppression efficacy of water mist which were affected by the type and concentration of metal chloride. On a mass basis, there is a fire suppression effectiveness relationship of MgCl2additive limits exist due to the associated limiting vapour pressure of the additive.

  3. SO/sub 2/ (G) to sulfate conversion rate in an oil-fired power plant plume in a fog bank

    SciTech Connect

    Eatough, D.J.; Arthur, R.J.; Cooper, J.A.; Eatough, N.J.; Hansen, L.D.; Hill, M.W.; Mangelson, N.F.; Richter, B.E.

    1983-06-01

    High acidity in rain fall cloud droplets and fog droplets in areas influenced by anthropogenic sources of SO/sub 2/ (g) and NO /SUB x/ (g) has been attributed to the formation of both H/sub 2/SO/sub 4/ and HNO/sub 3/. It has been suggested based on the analysis of field data, that rapid conversion of SO/sub 2/(g) to sulfate must occure in cloud or fog droplets. Data on the conversion of SO/sub 2/(g) to sulfate in water droplets is largely confined to the results of laboratory studies. Hegg and Hobbs have reported on the production of sulfate in wave clouds based on the measurement of particulate matter sulfate concentrations before and after passage of an air mass through the cloud. Because of major uncertainties in the measurement of the residence (and hence reaction) time of the air mass in the cloud, their results have large uncertainties. However, the oxidation rate in the more acidic clouds (pH of cloud droplets<5) was 20 + or - 33% SO/sub 2/(g) hr/sup -1/

  4. Effects of gas stream temperature on homogeneous SO{sub 2} to SO{sub 3} conversion via natural gas reburning

    SciTech Connect

    Bayless, D.J.; Khan, A.R.

    1998-07-01

    Because SO{sub 3} is more reactive than SO{sub 2}, applications for localized increases of SO{sub 3} concentrations in coal-fired power generation include lowering fly ash resistivity and improved performance of dry scrubbing systems to removal sulfur gas. Homogeneous superequilibrium of SO{sub 3} forms when SO{sub 2} passes through a flame in the presence of excess O{sub 2}. While this superequilibrium condition has been studied, little data exist about the effects of free stream gas temperature (as opposed to flame temperature) on this process. A pre-mixed methane flame was used to promote the conversion of SO{sub 2} to SO{sub 3} in a drop tube furnace with free stream gas temperatures from 450--1,000K. Experimental results form solid sampling and SO{sub 2}/SO{sub 3} measurements via wet chemistry coupled with numeric modeling of reactions and species concentrations indicate that a lower free stream temperature reduces the maximum conversion of SO{sub 2} to SO{sub 3} and considerably extends the duration of the super-equilibrium state. Results also indicate that the homogeneous enhancement of sulfur reactivity and increased duration of superequilibrium may increase sulfur capture by dry sorbents.

  5. Numerical study on the influence of hydrogen addition on soot formation in a laminar ethylene-air diffusion flame

    SciTech Connect

    Guo, Hongsheng; Liu, Fengshan; Smallwood, Gregory J.; Guelder, OEmer L.

    2006-04-15

    The influence of hydrogen addition to the fuel of an atmosphere pressure coflow laminar ethylene-air diffusion flame on soot formation was studied by numerical simulation. A detailed gas-phase reaction mechanism, which includes aromatic chemistry up to four rings, and complex thermal and transport properties were used. The fully coupled elliptic governing equations were solved. The interactions between soot and gas-phase chemistry were taken into account. Radiation heat transfer from CO{sub 2}, CO, H{sub 2}O, and soot was calculated using the discrete-ordinates method coupled to a statistical narrow-band-correlated K-based wide-band model. The predicted results were compared with the available experimental data and analyzed. It is indicated that the addition of hydrogen to the fuel in an ethylene-air diffusion flame suppresses soot formation through the effects of dilution and chemistry. This result is in agreement with available experiments. The simulations further suggest that the chemically inhibiting effect of hydrogen addition on soot formation is due to the decrease of hydrogen atom concentration in soot surface growth regions and higher concentration of molecular hydrogen in the lower flame region. (author)

  6. Effect of additional heat treatment of 2024-T3 on the growth of fatigue crack in air and in vacuum

    NASA Technical Reports Server (NTRS)

    Louwaard, E. P.

    1986-01-01

    In order to determine the influence of ductility on the fatigue crack growth rate of aluminum alloys, fatigue tests were carried out on central notched specimens of 2024-T3 and 2024-T8 sheet material. The 2024-T8 material was obtained by an additional heat treatment applied on 2024-T3 (18 hours at 192 C), which increased the static yield strength from 43.6 to 48.9 kgf/sq mm. A change in the ultimate strength was not observed. Fatigue tests were carried out on both materials in humid air and in high vacuum. According to a new crack propagation model, crack extension is supported to be caused by a slip-related process and debonding triggered by the environment. This model predicts an effect of the ductility on the crack growth rate which should be smaller in vacuum than in humid air; however, this was not confirmed. In humid air the crack-growth rate in 2024-T8 was about 2 times faster than in 2024-T3, while in vacuum the ratio was about 2.5. Crack closure measurements gave no indications that crack closure played a significant role in both materials. Some speculative explanations are briefly discussed.

  7. Task 2.0 -- Air quality assessment, control, and analytical methods: Subtask 2.11 -- Lactic acid FGD additives from sugar beet wastewater. Final report

    SciTech Connect

    Olson, E.S.

    1998-06-01

    Organic buffers maintain the pH of the scrubber slurry in flue gas desulfurization as the SO{sub 2} dissolves at the air-liquid interface. Inexpensive acids with an appropriate pKa are required for this application. The pKa of lactic acid (3.86) is between that of the interface and the recirculating slurry and will make soluble calcium ions available in large amounts. Currently lactic acid is somewhat expensive for this, but the project work will lead to development of a new source of inexpensive lactate. Microbial action during the storage and processing of sugar beets forms lactic acid in concentrations as high as 14 g/L in the processing water. The concentrations are lower than those occurring in conventional fermentation production of lactic acids, but since a considerable amount of water is involved in the processing of sugar beets in the Red River Valley, a substantial amount of lactic acid or calcium lactate could be recovered as a byproduct for use in flue gas desulfurization (FGD) and other applications. The feasibility of two novel lactate recovery schemes applicable to dilute streams was evaluated in the project.

  8. Introducing deep eutectic solvents to polar organometallic chemistry: chemoselective addition of organolithium and Grignard reagents to ketones in air.

    PubMed

    Vidal, Cristian; García-Álvarez, Joaquín; Hernán-Gómez, Alberto; Kennedy, Alan R; Hevia, Eva

    2014-06-01

    Despite their enormous synthetic relevance, the use of polar organolithium and Grignard reagents is greatly limited by their requirements of low temperatures in order to control their reactivity as well as the need of dry organic solvents and inert atmosphere protocols to avoid their fast decomposition. Breaking new ground on the applications of these commodity organometallics in synthesis under more environmentally friendly conditions, this work introduces deep eutetic solvents (DESs) as a green alternative media to carry out chemoselective additions of ketones in air at room temperature. Comparing their reactivities in DES with those observed in pure water suggest that a kinetic activation of the alkylating reagents is taking place, favoring nucleophilic addition over the competitive hydrolysis, which can be rationalized through formation of halide-rich magnesiate or lithiate species. PMID:24771680

  9. Studies of SO/sub 2/ impact on lichens

    SciTech Connect

    Fields, R.D.

    1983-01-01

    On the basis of sensitivity, cost, portability and time, the membrane permeability test was determined to be the most effective method for assessing SO/sub 2/ impact on lichens. After 4 hours exposure to 2 ppm SO/sub 2/ the only method which was significantly more sensitive than the others was potassium efflux. However, following exposure for 8 and 12 hours all four methods differed significantly with potassium efflux being most sensitive, followed by total conductivity, photosynthesis and respiration. The amount of change detected by each method was not influenced by species. The effects of 1 and 2 ppm gaseous SO/sub 2/ at 4, 8 and 12 hours of exposure on photosynthesis and carbohydrate transfer in the lichens Parmelia chlorochroa and Collema polycarpon were examined. Photosynthesis in both species was initially stimulated following exposure to SO/sub 2/ but prolonged exposure resulted in depression of photosynthesis. Carbohydrate transfer decreased in both species but increased significantly after 12 hours exposure in C. polycarpon.

  10. Acid rain program emissions scorecard 1997. SO[sub 2], NO[sub x], heat input, and CO[sub 2] emission trends in the electric utility industry

    SciTech Connect

    Not Available

    1999-01-01

    Established under Title IV of the Clean Air Act Amendments of 1990, the Acid Rain Program requires the electric utility industry to reduce emissions of sulfur dioxide (SO[sub 2]) and nitrogen oxides (NO[sub x]), the pollutants that cause acid rain. To ensure that the desired emission reductions are achieved, the program implements an innovative market-based regulatory approach with utilities having flexible compliance options. After each calendar year, EPA determines the compliance of each facility relating to its SO[sub 2] and NO[sub x] emissions requirements and publishes a report documenting the results.

  11. A PRINCIPAL COMPONENT ANALYSIS OF THE CLEAN AIR STATUS AND TRENDS NETWORK (CASTNET) AIR CONCENTRATION DATA

    EPA Science Inventory

    The spatial and temporal variability of ambient air concentrations of SO>2, SO>42-, NO3, HNO3, and NH4+ obtained from EPA's CASTNet was examined using an objective, statistically based technique...

  12. Results of SO{sub 2}, NO{sub x}, and CO monitoring at McMurdo Station, Antarctica

    SciTech Connect

    Lugar, R.M.

    1993-05-01

    This report presents the results of ambient air monitoring of carbon monoxide (CO), sulfur dioxide (SO{sub 2}), nitric oxide (NO), nitrogen dioxide (NO{sub 2}), and total oxides of nitrogen (NO{sub x}) performed during the final weeks of the 1992-1993 austral summer in the vicinity of McMurdo Station, Antarctica. Commercially available, high sensitivity ambient air gas analyzers were used to continuously measure gas concentrations at two locations over a two and a three week time period respectively. Sampling site selection, sampling procedures and quality assurance procedures used for this effort were consistent with U.S. Environmental Protection Agency guidelines for local ambient air quality networks. CO, SO{sub 2}, and NO{sub 2} concentrations measured were below the associated U.S. National Ambient Air Quality Standards. Carbon monoxide levels measured at both locations were near or below the instrument detection limit of 0.1 part per million (ppm). Hourly average SO{sub 2} concentrations ranged from below the detection limit of 1 part per billion (ppb) to a single maximum hourly average value of 60 ppb. Hourly average NO{sub 2} concentrations ranged from below the detection limit of 1 ppb to a single maximum hourly average value of 26 ppb. The impact on local air quality of ships docked at an ice pier was observed and quantified. The initial baseline effort demonstrated that site selection and sampling equipment performance were satisfactory, and provided useful data for assessing the impact of McMurdo operations on the local ambient air quality.

  13. Why are allowance prices so low? An analysis of the SO{sub 2} emissions trading program

    SciTech Connect

    Ellerman, A.D.; Montero, J.P.

    1997-12-31

    This paper presents an analysis of the reduction in SO{sub 2} emissions by electric utilities between 1985 and 1993. We find that, as of 1993, emissions had been reduced for reasons largely unrelated to the emission reduction mandate incorporated in Title IV of the 1990 Clean Air Act Amendments. The principal reason appears to be the change in the economics of coal choice that resulted from the remarkable decline in rail rates for low sulfur western coal delivered to higher sulfur coal-fired plants in the Midwest. Consequently, one of the reasons that allowance prices are lower than expected is that less sulfur need be removed to meet the Title IV caps on aggregate SO{sub x} emissions.

  14. Status of flue-gas treatment technologies for combined SO[sub 2]/NO[sub x] reduction

    SciTech Connect

    Livengood, C.D. . Energy Systems Div.); Markussen, J.M. )

    1993-01-01

    Enactment of the Clean Air Act Amendments and passage of state legislation leading to more stringent nitrogen oxides (NO.) regulations have fueled research and development efforts on the technologies for the combined control of sulfur dioxide (SO[sub 2]) and NO[sub x]. The integrated removal of both SO[sub 2] and NO[sub x] in a single system can offer significant advantages over the use of several separate processes, including such factors as reduced system complexity, better operability, and lower costs. This paper reviews the status of a number of integrated flue-gas-cleanup systems that have reached a significant stage of development, focusing on post-combustion processes that have been tested or are ready for testing at the pilot scale or larger. A brief process description, a summary of the development status and performance achieved to date, pending commercialization issues, and process economics (when available) are given for each technology.

  15. CHEMISTRY OF SO{sub 2} ON MODEL METAL AND OXIDE CATALYSTS: PHOTOEMISSION AND XANES STUDIES

    SciTech Connect

    RODRIGUEZ,J.A.; JIRSAK,T.; CHATURVEDI,S.; HRBEK,J.; FREITAG,A.; LARESE,J.Z.

    2000-07-09

    High-resolution synchrotron based photoemission and x-ray absorption spectroscopy have been used to study the interaction of SO{sub 2} with a series of metals and oxides. The chemistry of SO{sub 2} on metal surfaces is rich. At low coverages, the molecule fully decomposes into atomic S and O. At large coverages, the formation of SO{sub 3} and SO{sub 4} takes place. The following sequence was found for the reactivity of the metals towards SO{sub 2}: Pt {approx} Rh < Ru < Mo << Zn, Sn, Cs. Alloying can be useful for reducing the chemical affinity of a metal for SO{sub 2} and controlling S poisoning. Pd atoms bonded to Rh and Pt atoms bonded to Sn interact weakly with SO{sub 2}. In general, SO{sub 2} mainly reacts with the O centers of metal oxides. SO{sub 4} is formed on CeO{sub 2} and SO{sub 3} on ZnO. On these systems there is no decomposition of SO{sub 2}. Dissociation of the molecule is observed after introducing a large amount of Ce{sup 3+} sites in ceria, or after depositing Cu or alkali metals on the oxide surfaces. These promote the catalytic activity of the oxides during the destruction of SO{sub 2}.

  16. Separability of SO[sub 2] from SO[sub 2]/N[sub 2] mixture through sulfoxide-modified poly(vinyl alcohol) and cellulose membranes

    SciTech Connect

    Imai, Kiyokazu; Shiomi, Tomoo; Tezuka, Yasuyuki; Itamochi, Hiroko; Miya, Masamitsu )

    1993-06-05

    Separability of SO[sub 2] from mixtures of SO[sub 2] and N[sub 2] gases was studied for membranes of poly(vinyl alcohol) (PVA) and cellulose modified with methyl, ethyl, t-butyl, and phenyl vinyl sulfoxides. Of these sulfoxide-modified polymers, the phenyl vinyl sulfoxide-modified PVA membranes were found to give the best separation of SO[sub 2]. In the phenyl vinyl sulfoxide-modified PVA membranes, the permeability coefficient of SO[sub 2] increased with sulfoxide content while separability of SO[sub 2] was maximum at a sulfoxide content of 23.5 mol %; the separation factor of SO[sub 2] was about 170 at this sulfoxide content.

  17. High SO{sub 2} removal efficiency testing: Evaluation of high efficiency test results at Hoosier Energy`s Merom Station

    SciTech Connect

    1996-04-22

    Tests were conducted at Hoosier Energy`s Merom Station 535-MW Units 1 and 2 wet limestone flue gas desulfurization (FGD) systems to evaluate options for achieving high SO{sub 2} removal efficiency. The options tested included use of dibasic acid (DBA) and sodium formate additives as well as operation at higher reagent ratios (higher pH set points). In addition to the tested options, the effectiveness of other potential options was simulated using the Electric Power Research Institute`s FGD Process Integration and Simulation Model (FGDPRISM) after it was calibrated to the system. An economic analysis was done to determine the cost effectiveness of each option. A summary of results is given on the following: SO{sub 2} removal performance; additive consumption; and SO{sub 2} removal upgrade economics.

  18. Duct injection for SO{sub 2} control, Design Handbook, Volume 1, Process design and engineering guidelines

    SciTech Connect

    1995-09-01

    PETC developed a comprehensive program of coal-related, acid-rain research and development with a major activity area centering on flue gas cleanup and control of SO{sub 2} emissions. Particular emphasis was placed on the retrofit measures for older coal-fired power plants which predate the 1971 New Source Performance Standards. Candidate emission control technologies fall into three categories, depending upon their point of application along the fuel path (i.e., pre, during, or post combustion). The post-combustion, in-duct injection of a calcium-based chemical reagent seemed promising. Preliminary studies showed that reagent injection between the existing air heater and electrostatic precipitator (ESP) could remove between 50-60% of the SO{sub 2} and produce an environmentally safe, dry, solid waste that is easily disposed. Although SO{sub 2} removal efficiencies were less, the estimated capital costs for duct injection technology were low making the economics of duct injection systems seem favorable when compared to conventional wet slurry scrubbers under certain circumstances. With the promulgation of the Clean Air Act Amendments of 1990 came more incentive for the development of low capital cost flue gas desulfurization (FGD) processes. A number of technical problems had to be resolved, however, before duct injection technology could be brought to a state of commercial readiness. The Duct Injection Technology Development Program was launched as a comprehensive, four-year research effort undertaken by PETC to develop this new technology. Completed in 1992, this Duct Injection Design Handbook and the three-dimensional predictive mathematical model constitute two primary end products from this development program. The aim of this design handbook and the accompanying math model is to provide utility personnel with sufficient information to evaluate duct injection technology against competing SO{sub 2} emissions reduction strategies for an existing plant.

  19. Superposition-additive approach: thermodynamic parameters of clusterization of monosubstituted alkanes at the air/water interface.

    PubMed

    Vysotsky, Yu B; Belyaeva, E A; Fomina, E S; Fainerman, V B; Aksenenko, E V; Vollhardt, D; Miller, R

    2011-12-21

    The applicability of the superposition-additive approach for the calculation of the thermodynamic parameters of formation and atomization of conjugate systems, their dipole electric polarisabilities, molecular diamagnetic susceptibilities, π-electron circular currents, as well as for the estimation of the thermodynamic parameters of substituted alkanes, was demonstrated earlier. Now the applicability of the superposition-additive approach for the description of clusterization of fatty alcohols, thioalcohols, amines, carboxylic acids at the air/water interface is studied. Two superposition-additive schemes are used that ensure the maximum superimposition of the graphs of the considered molecular structures including the intermolecular CH-HC interactions within the clusters. The thermodynamic parameters of clusterization are calculated for dimers, trimers and tetramers. The calculations are based on the values of enthalpy, entropy and Gibbs' energy of clusterization calculated earlier using the semiempirical quantum chemical PM3 method. It is shown that the proposed approach is capable of the reproduction with sufficiently enough accuracy of the values calculated previously. PMID:22042000

  20. Effect of SO>2 on oxidation of metallic materials in CO2/H2O-rich gases relevant to oxyfuel environments

    SciTech Connect

    Huczkowski, P.; Olszewski, T.; Schiek, M.; Lutz, B.; Holcomb, G.; Shemet, V.; Meier, G. H.; Singheiser, L.; Quadakkers, W. J.

    2012-09-19

    This report is a description of research performed by the Jülich Research Centre. Their conclusions outline the effects of SO>2 additions on oxide formations and the interaction of other gases in oxvyfuel environments.

  1. Development of the advanced coolside sorbent injection process for SO{sub 2}

    SciTech Connect

    Withum, J.A.; Maskew, J.T.; Rosenhoover, W.A.

    1995-11-01

    The goal of this work was to develop a low-capital-cost process capable of over 90% SO{sub 2} removal as an economically attractive option for compliance with the Clean Air Act. The Advanced Coolside Process uses a contactor to simultaneously remove fly ash and saturate the flue gas with water, followed by sorbent injection into the highly humid flue gas and collection of the sorbent by the existing particulate collector High sorbent utilization is achieved by sorbent recycle. The original performance targets of 90% SO{sub 2} removal and 60% sorbent utilization were exceeded in 1000 acfm pilot plant operations using commercial hydrated lime as the only sorbent. Process optimization simplified the process equipment, resulting in significant cost reduction. Recent accomplishments include completion of equipment testing and sorbent optimization, a waste management study, and a long-term performance test. An economic evaluation for the optimized process projects capital costs 55% to 60 % less than those of limestone forced oxidation wet FGD. The projected levelized control cost is 15% to 35% lower than wet FGD (25% lower for a 260 MWe plant burning a 2.5% sulfur coal), depending on plant size and coal sulfur content.

  2. SO[sub 2]: Apoplastic peroxidase is more sensitive than photosynthesis

    SciTech Connect

    Pfanz, H.; Schults, G.; Oppmann, B. )

    1993-05-01

    Leaves of barley (Hordeum vulgare L.) were fumigated for 24h (-48h) measurements of maximum photosynthetic capacity were carried out. In parallel, intercellular washing fluids (IWF) from the leaves were collected and examined for their ability to peroxidatively oxidize sulfite. Although the leaves had taken up the SO[sub 2], as evidenced by an increase in total sulfur (as well as in the sulfate content) no reduction was found in the maximum ability to photoreduce CO[sub 2] under all conditions applied. On the other hand, there was marked increase in the activity of the IWF to oxidize sulfite to sulfate. Within 5 hours after the start of the fumigation, a distinct and significant rise in the sulfite-oxidizing activity was found. After one day, sulfite-oxidation rates of the cell wall extracts had more than doubled, in comparison to unfumigated controls. In extracts of leaves from fumigated plants, the increase of the sulfite oxidizing activity was negligible during the time of the experiment. Only extracts isolated from the leaf cell walls showed an enhanced activity. Unfumigated control plants never revealed a change in activity, neither in the leaf homogenate, nor in the IWF. These findings suggest that mechanisms in the cell walls of leaves are much more sensitive to (and possibly triggered by) air pollutants like SO[sub 2], than reactions of the protoplast. The sulfite oxidation in the apoplast can be regarded as a forward defense mechanism to protect symplastic reactions.

  3. Economics of pollution trading for SO{sub 2} and NOx

    SciTech Connect

    Dallas Burtraw; David A. Evans; Alan Krupnick; Karen Palmer; Russell Toth

    2005-03-15

    For years economists have urged policymakers to use market-based approaches such as cap-and-trade programs or emission taxes to control pollution. The sulphur dioxide (SO{sub 2}) allowance market created by Title IV of the 1990 US Clean Air Act Amendments represents the first real test of the wisdom of economists' advice. Subsequent urban and regional applications of NOx emission allowance trading took shape in the 1990s in the United States, culminating in a second large experiment in emission trading in the eastern United States that began in 2003. This paper provides an overview of the economic rationale for emission trading and a description of the major US programs for SO{sub 2} and nitrogen oxides. These programs are evaluated along measures of performance including cost savings, environmental integrity, and incentives for technological innovation. The authors offer lessons for the design of future programs including, most importantly, those reducing carbon dioxide. 128 refs., 1 fig., 1 tab.

  4. Strain-induced extinction of hydrogen-air counterflow diffusion flames - Effects of steam, CO2, N2, and O2 additives to air

    NASA Technical Reports Server (NTRS)

    Pellett, G. L.; Northam, G. B.; Wilson, L. G.

    1992-01-01

    A fundamental study was performed using axisymmetric nozzle and tubular opposed jet burners to measure the effects of laminar plug flow and parabolic input velocity profiles on the extinction limits of H2-air counterflow diffusion flames. Extinction limits were quantified by 'flame strength', (average axial air jet velocity) at blowoff of the central flame. The effects of key air contaminants, on the extinction limits, are characterized and analyzed relative to utilization of combustion contaminated vitiated air in high enthalpy supersonic test facilities.

  5. Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report, No. 14, June 1, 1994--August 31, 1994

    SciTech Connect

    1997-01-01

    The objective of the NOXSO Demonstration Project (NDP), with cost-shared funding support from DOE, is to design, construct, and operate a commercial-scale flue gas cleanup system utilizing the NOXSO process. The NDP consists of the NOXSO plant and sulfur recovery unit, designed to remove SO{sub 2} and NO{sub x} from flue gas and produce elemental sulfur by-product, and the liquid SO{sub 2} plant and air separation unit, designed to process the elemental sulfur into liquid SO{sub 2}. The NOXSO plant and sulfur recovery unit will be constructed at ALCOA Generating Corporation`s (AGC) Warrick Power Plant near Evansville, Indiana, and will treat all of the flue gas from the 150-MW Unit 2 boiler. The elemental sulfur produced will be shipped to the Olin Charleston Plant in Charleston, Tennessee, for conversion into liquid SO{sub 2}.

  6. From SO{sub 2} to greenhouse gases: trends and events shaping future emissions trading programs in the United States

    SciTech Connect

    Joseph Kruger

    2005-06-15

    Cap-and-trade programs have become widely accepted for the control of conventional air pollution in the United States. However, there is still no political consensus to use these programs to address greenhouse gases. Meanwhile, in the wake of the success of the US SO{sub 2} and NOx trading programs, private companies, state governments, and the European Union are developing new trading programs or other initiatives that may set precedents for a future national US greenhouse gas trading scheme. This paper summarizes the literature on the 'lessons learned' from the SO{sub 2} trading program for greenhouse gas trading, including lessons about the potential differences in design that may be necessary because of the different sources, science, mitigation options, and economics inherent in greenhouse gases. The paper discusses how the programs and initiatives mentioned above have been shaped by lessons from past trading programs and whether they are making changes to the SO{sub 2} model to address greenhouse gases. It concludes with an assessment of the implications of these initiatives for a future US national greenhouse gas trading program. 91 refs., 2 tabs.

  7. Making appropriate comparisons of estimated and actual costs of reducing SO{sub 2} emissions under Title IV

    SciTech Connect

    Smith, A.E.

    1998-12-31

    A current sentiment within some parts of the environmental policy community is that market-based regulatory approaches such as emissions trading have proven so effective that actual costs will be only a small fraction of what ex ante cost estimation procedures would project. With this line of reasoning, some have dismissed available cost estimates for major proposed new regulations, such as the new PM and ozone NAAQS, as not meaningful for policy decisions. The most commonly used evidence in support of this position is the experience with SO{sub 2} reductions under Title IV of the 1990 Clean Air Act Amendments. In Title IV, a market for emissions allowances has been used to achieve reductions in sulfur dioxides (SO{sub 2}) to ameliorate acid rain. It is commonly asserted today that the cost of achieving the SO{sub 2} emissions reductions has been only one-tenth or less of what Title IV was originally expected to cost. This paper demonstrates that, to the contrary, actual costs for SO{sub 2} reductions remain roughly in line with original estimates associated with Title IV. Erroneous conclusions about Title IV`s costs are due to inappropriate comparisons of a variety of different measures that appear to be comparable only because they are all stated in dollars per ton. Program cost estimates include the total costs of a fully-implemented regulatory program. The very low costs of Title IV that are commonly cited today are neither directly reflective of a fully implemented Title IV, (which is still many years away) nor reflective of all the costs already incurred. Further, a careful review of history finds that the initial cost estimates that many cite were never associated with Title IV. Technically speaking, people are comparing the estimated control costs for the most-costly power plant associated with earlier acid rain regulatory proposals with prices from a market that do not directly reflect total costs.

  8. Claus catalysis. 3. An FTIR study on the sequential adsorption of SO/sub 2/ and H/sub 2/S on the alumina catalyst

    SciTech Connect

    Datta, A.; Cavell, R.G.

    1985-01-31

    The sequential adsorption of H/sub 2/S and SO/sub 2/ on ..gamma..-alumina catalyst activated at 400/sup 0/C has been studied by Fourier transform infrared (FTIR) spectroscopy. When incremental amounts of H/sub 2/S were added to a sample of alumina upon which SO/sub 2/ had been preadsorbed, the Claus reaction took place but the species responsible for the band at 1055 cm-/sup 1/ (characteristic of SO/sub 2/ adsorbed on alumina) showed very low reactivity toward H/sub 2/S. No infrared bands due to adsorbed H/sub 2/S were observed, but this cannot be taken as conclusive evidence for the absence of adsorbed H/sub 2/O. On addition of SO/sub 2/ to an alumina sample on which H/sub 2/S had been preadsorbed, the Claus reaction also proceeded but to a much lesser extent probably because of the dissociative adsorption of part of the preadsorbed H/sub 2/S. Also, in this case bands due to adsorbed SO/sub 2/ were observed throughout the reaction. The dependence of the rate of the Claus reaction on the activation temperature of the catalyst, the nature and mechanism of catalyst poisoning, and an alternative approach for carrying out the Claus reaction are also discussed. 13 refs., 5 figs.

  9. LIFAC flue gas desulfurization process an alternative SO{sub 2} control strategy

    SciTech Connect

    Patel, J.G.; Vilala, J.

    1995-12-01

    This paper discusses the results from two recently completed LIFAC flue gas desulfurization plants - 300 MW Shand lignite powered station owned by Saskatchewan Power Corporation and 60 MW Whitewater Valley high sulfur coal fired station owned by Richmond Powerand Light. LIFACis a dry FGD process in which limestone is injected into the upper regions of the boiler furnace and an activation reactor is used to humidify the unreacted limestone to achieve additional sulfur capture. The performance in both plants indicates that 70 to 80% sulfur is removed at a Ca/S ratio of 2. Cost performance data from these plants has shown that LI FAC both on construction cost and $/ton SO{sub 2} removed basis is very cost competitive compared to other SO{sub 2} control technologies. The Richmond plant has been realized under the auspices of the U.S. Department of Energy`s Clean Coal Technology program. The Shand plant is the first commercial installation in North America. The paper also discusses highlights of operating and maintenance experience, availability and handling of the solid waste product.

  10. Effects of inhaled sulfur dioxide (SO/sub 2/) on pulmonary function in healthy adolescents: exposure to SO/sub 2/ alone or SO/sub 2/ + sodium chloride droplet aerosol during rest and exercise

    SciTech Connect

    Koenig, J.Q.; Pierson, W.E.; Horike, M.; Frank, R.

    1982-01-01

    Statistically significant changes in pulmonary functional measurements in asthmatic adolescents exposed to sulfur dioxide (SO/sub 2/) at reset and during exercise were recently reported. To determine whether those results were due to the subjects' adolescence or to their asthma, the identical exposures were repeated in healthy adolescents. The healthy subjects showed small, statistically significant changes after exposure to SO/sub 2/, but these changes were slight compared to those seen in the asthmatic adolescents. It was concluded that asthmatic adolescents are much more sensitive to the effects of inhaled SO/sub 2/ than are healthy adolescents. (JMT)

  11. Process for removing SO/sub x/ and NO/sub x/ compounds from gas streams

    SciTech Connect

    Hass, R.H.

    1989-02-14

    A process is described for removing SO/sub x/ compounds from a feed gas stream and producing a purified gas stream of reduced SO/sub x/ content, which process comprises: contacting a feed gas stream containing SO/sub x/ compounds; withdrawing from step (1) a liquid stream of spent absorbent containing the absorbed SO/sub x/ compounds; regenerating the spent absorbent back to a form active for absorbing SO/sub x/ compounds; separating the products of step (3) into a liquid stream containing a regenerated absorbent and a product gas stream containing H/sub 2/S; recycling at least some of the liquid stream containing regenerated absorbent; and recovering the purified gas stream of reduced SO/sub x/ content and the product gas stream containing H/sub 2/S.

  12. Apparatus and method for improving electrostatic precipitator performance by plasma reactor conversion of SO.sub.2 to SO.sub.3

    DOEpatents

    Huang, Hann-Sheng; Gorski, Anthony J.

    1999-01-01

    An apparatus and process that utilize a low temperature nonequilibrium plasma reactor, for improving the particulate removal efficiency of an electrostatic precipitator (ESP) are disclosed. A portion of the flue gas, that contains a low level of SO.sub.2 O.sub.2 H.sub.2 O, and particulate matter, is passed through a low temperature plasma reactor, which defines a plasma volume, thereby oxidizing a portion of the SO.sub.2 present in the flue gas into SO.sub.3. An SO.sub.2 rich flue gas is thereby generated. The SO.sub.3 rich flue gas is then returned to the primary flow of the flue gas in the exhaust treatment system prior to the ESP. This allows the SO.sub.3 to react with water to form H.sub.2 SO.sub.4 that is in turn is absorbed by fly ash in the gas stream in order to improve the removal efficiency of the EPS.

  13. Additional double-wall roof in single-wall, closed, convective incubators: Impact on body heat loss from premature infants and optimal adjustment of the incubator air temperature.

    PubMed

    Delanaud, Stéphane; Decima, Pauline; Pelletier, Amandine; Libert, Jean-Pierre; Stephan-Blanchard, Erwan; Bach, Véronique; Tourneux, Pierre

    2016-09-01

    Radiant heat loss is high in low-birth-weight (LBW) neonates. Double-wall or single-wall incubators with an additional double-wall roof panel that can be removed during phototherapy are used to reduce Radiant heat loss. There are no data on how the incubators should be used when this second roof panel is removed. The aim of the study was to assess the heat exchanges in LBW neonates in a single-wall incubator with and without an additional roof panel. To determine the optimal thermoneutral incubator air temperature. Influence of the additional double-wall roof was assessed by using a thermal mannequin simulating a LBW neonate. Then, we calculated the optimal incubator air temperature from a cohort of human LBW neonate in the absence of the additional roof panel. Twenty-three LBW neonates (birth weight: 750-1800g; gestational age: 28-32 weeks) were included. With the additional roof panel, R was lower but convective and evaporative skin heat losses were greater. This difference can be overcome by increasing the incubator air temperature by 0.15-0.20°C. The benefit of an additional roof panel was cancelled out by greater body heat losses through other routes. Understanding the heat transfers between the neonate and the environment is essential for optimizing incubators. PMID:27387899

  14. Boundary lubrication of formulated C-ether in air to 300 deg C. 1: Phosphorus ester additives

    NASA Technical Reports Server (NTRS)

    Jones, W. R., Jr.; Hady, W. F.

    1972-01-01

    Friction and wear measurements were made on CVM M-50 steel lubricated with three C-ether (modified polyphenyl ether) formulations in dry and wet air. Results were compared to those obtained with a formulated Type 2 ester and the C-ether base fluid. A ball-on-disk sliding friction apparatus was used. Experimental conditions were a 1-kilogram load, a 17-meter-perminute (100-rpm) surface speed, and a 25 to 300 C (77 to 572 F) disk temperature range. The C-ether base fluid and the three formulated C-ether fluids yielded lower wear than the Type 2 ester over the entire temperature range. All C-ether fluids exhibited slightly higher friction coefficients than the ester from 150 to 300 C (302 to 572 F) and similar values from 25 to 150 C (77 to 302 F). In general, lower wear rates were observed with the C-ethers when tested in wet air as compared to a dry air atmosphere.

  15. Effectiveness of calcium magnesium acetate as an SO[sub x] sorbent in coal combustion

    SciTech Connect

    Levendis, Y.A.; Zhu, W.; Wise, D.L. ); Simons, G.A. )

    1993-05-01

    A fundamental study was conducted on the effectiveness of the chemical calcium magnesium acetate (CMA) as a sulfur capture agent during combustion of pulverized coal. It was based on high-temperature laboratory-bench experiments with the scope of exploring the use of CMA as a dry scrubbing'' medium for in-boiler injection. Two methods of CMA introduction in the furnace were considered: dry-spraying fine powders of the chemical and wet-spraying aqueous solutions to generate fine aerosols. It considered conditions pertinent to post-flame in-boiler injection of CMA to identify optimum temperatures and residence times. In addition to the versatility of the water-soluble CMA to enable spray drying injection and therefore eliminate grinding costs, there are other attractive features. Mainly, its ability to form highly cenospheric, popcorn''-like, oxide particles on heating to high temperatures. These cenospheres possess thin, porous walls with blowholes that enable penetration of the SO[sub 2] in the interior of the particle which promotes high sorbent utilization. SO[sub 2] captures in the order of 90% were achieved with dry-injection of the chemical at furnace gas temperatures of about 1,000[degree]C, a Ca/S ratio of 2, and particle size of [approximately] 50[mu]m. Moreover, CMA was superior (by over 40%) to either CaCO[sub 3] or Ca(OH)[sub 2] in sulfur capture effectiveness per unit mass of calcium. This commercially obtained CMA was even superior to reagent-grade calcium acetate (by as much as 30%), again per unit mass of calcium. The utilization of CMA and calcium acetate depended on the cenosphere wall thickness, rather than the particle size and, thus, outperformed other sorbents regardless of the size of the resulting oxide particles.

  16. Evaluation of air pollution abatement systems for multiple-hearth sewage sludge incinerators

    SciTech Connect

    Annamraju, G.; Gerstle, R.W.; Shah, Y.M.; Arora, M.L.

    1986-09-01

    Capital and annual costs were calculated for the application of six different air-pollution-control system options to municipal sewage-sludge incinerators that were using multiple-hearth furnaces. The systems involved three principal types of air-pollution equipment - wet scrubbers, fabric filters, and electrostatic precipitators - applied to three different plant sizes (plants incinerating 36, 72, and 300 tons of dry sludge per day in one, two, and eight multiple-hearth furnaces, respectively). The six options were: (1) venturi/tray scrubber with a 40-inch pressure drop, (2) fabric filter system operating at 500 deg and equipped with an upstream temperature control, (3) fabric filter system operating at 500 deg and equipped with a heat exchanger and a scrubber for SO/sub 2/ reduction, (4) electrostatic precipitator (ESP) with upstream limited temperature and humidity control, (5) same as Option 4 but with an additional downstream wet scrubber for SO/sub 2/ reduction, and (6) ESP with upstream temperature control and an SO/sub 2/ scrubber. Technical feasibility studies indicated that all three types of controls could achieve a total particulate removal efficiency of 99 percent. The venturi/tray scrubber option entailed the lowest capital cost, but annual operating costs were highest because of the high pressure drops and increased energy use.

  17. A reversible zwitterionic SO>2-binding organic liquid

    SciTech Connect

    Heldebrant, David J; Koech, Phillip K; Yonker, Clement R

    2010-01-05

    As fossil fuel consumption continues, there is much attention being focused on capturing acid gas emissions from power plants. We have recently investigated SO>2-binding organic liquids (SO>2BOLs) as means to reversibly capture and release SO>2 selectively over CO2.1 SO>2BOLs are mixtures of tertiary amines and alcohols, which bind SO>2 as liquid ammonium alkylsulfite salts. Tertiary amines selectively bind SO>2 over CO2 because tertiary amines are basic enough to accept a proton from sulfurous and alkylsulfurous acids but not carbonic or alkylcarbonic acids. This is in contrast to other groups who absorb SO>2 physically in ionic liquids2-4 or chemically absorb SO>2 in organic systems5-7 or as irreversible aqueous bisulfite or sulfite salts.8-11 Our dual component SO>2BOL ionic liquids can contain up to 47% SO>2 by mass, have low specific heats, and can be desulfoxylated by heating to 90ºC.1 We believed that a bifunctional tertiary alkanol amine would be able to capture SO>2 comparable to our binary SO>2BOL system. We present here the first reversible zwitterionic liquid produced from the reaction of SO>2 with N,N-dibutylundecanolamine (DBUA). The SO>2 is chemically bound through the alcohol moiety as an alkylsulfite, which we believe is stabilized by hydrogen bonding through the protonated amine portion of the molecule. Our recent interest in SO>2BOLs led us to explore the possible reaction of aprotic alkanolamines with SO>2 to form single-component SO>2BOLs. A symbiotic pairing of the base and the alcohol on one molecule allows for a simple unimolecular system compared to the binary SO>2BOL system. The bifunctional molecule also would have reduced volatility compared to tertiary amines due to increased hydrogen bonding from the alcohol moiety. To our knowledge

  18. Enhanced anthocyanin production from grape callus in an air-lift type bioreactor using a viscous additive-supplemented medium.

    PubMed

    Honda, Hiroyuki; Hiraoka, Kousuke; Nagamori, Eiji; Omote, Mariko; Kato, Yoshihito; Hiraoka, Setsuro; Kobayashi, Takeshi

    2002-01-01

    An N-medium containing carboxymethyl cellulose (CMC) was applied to an air-lift type bioreactor culture of grape (Vitis vinifera cv. Bailey alicant A.) callus, and anthocyanin production was investigated. Grape callus grew well at an air flow rate of 80 ml/min and anthocyanin production was significantly increased in the N-medium, reaching 17 mg/l after 7 d of culture. The anthocyanin content of the N-medium was about two times higher than that of the conventional medium without CMC. The effect of air flow rate was also investigated within the range from 40 to 160 ml/min. A twofold increase in anthocyanin content was obtained at all the air flow rates tested in the N-medium. The distribution of grape callus size obtained after 7 d of the bioreactor culture was investigated. The average callus size was 490 mum which was 1.6 times larger than that obtained in the conventional medium. It was found that large calli with a relatively high anthocyanin pigment content were formed in the bioreactor culture using the N-medium. The fluid dynamics in the bioreactor was also investigated at three points (top, middle and bottom) in the bioreactor by laser doppler velocimetry. The average axial velocity of the circulated medium was 0.4 times lower than that of the conventional medium while their average radial velocities were almost the same (zero). The standard deviation of radial velocity fluctuation in the N-medium was also 0.4 times less than that in the conventional medium. These results suggest that turbulent flow occurred in the bioreactor culture using the conventional medium and the degree of turbulent flow decreased significantly when 0.8% CMC was added to the medium to prepare the N-medium. A change of the flow pattern is considered to be the cause of the decrease in hydrodynamic stress, resulting in enhanced pigment production due to the enlargement of the callus. PMID:16233283

  19. Establishment of urban air quality prediction system

    SciTech Connect

    Ben-Jei Tsuang; Jime-Ming Huang

    1996-12-31

    By using the data of Taipei metropolitan and Taichung city, it was found that the concentrations of the PM{sub 10} and SO{sub 2} were strongly associated with wind speed, rain, surface layer stability and their initial concentrations. Among these factors, stability in the atmospheric surface layer was not fully addressed in traditional box model. A new box model formula was derived to include the stability parameter. After analysis of exchange/removal mechanisms operating in the PBL by using this new model, we find that the near ground pollutant concentration after reaching steady state is dose to q{sub 0}l/2ul{sub e} under stable, low wind speed and rainless day, where q{sub 0} is emission rate, 1 length of a city, u wind speed and l{sub e} stability scale length. Under calm wind speed in addition to the aforementioned conditions, the air quality became most deteriorated and close to q{sub 0}/V{sub d}, where V{sub d} is dry deposition rate. This formula works well in simulating PM{sub 10} and SO{sub 2} concentration of Pancho and Taichung city. In addition, this formula also can handle most of the deteriorated days.

  20. The increased concentration of SO{sub 2} and threat to the largest mangrove forest of the world - the Sundarbans

    SciTech Connect

    Ahmad, J.U.; Ullah, S.S.; Carmichael, G.R.; Haque, R.

    1996-12-31

    The atmospheric concentration of SO{sub 2} was monitored in two different sites, Khulna and Savar in Bangladesh as a part of Rains Asia Atmos Module, Phase I Project. The results show that the winter concentration of SO{sub 2} in Khulna is 3 to 4 times higher than the summer concentrations, which is also higher compared to measurements at Savar which is adjacent to Dhaka city. Based on these facts and seasonal wind pattern, trans-boundary air pollution has been suggested. Khulna is in the southwestern part of Bangladesh and this area harbors the largest mangrove forest of the world, the Sundarbans. Sundari trees are the main trees of the Sundarban ecosystem. During the last few years, many of the Sundari trees, which are quite susceptible to pH stress, are dying from the top. The unusual winter increase of atmospheric sulphurdioxide has been assigned to be one of the reasons for the top dying. Other factors might be the increase of salinity and diminished flow of water.

  1. Emerging flue-gas cleanup technologies for combined control of SO{sub 2} and NO{sub x}

    SciTech Connect

    Livengood, C.D.; Markussen, J.M.

    1994-06-01

    Enactment of the 1990 Clean Air Act Amendments, as well as passage of legislation at the state level has raised the prospect of more stringent nitrogen oxides (NO{sub x}) emission regulations and has fueled research and development efforts on a number technologies for the combined control of sulfur dioxide (SO{sub 2}) and NO{sub x}. The integrated removal of both SO{sub 2} and NO{sub x} in a single system can offer significant advantages over the use of several separate processes, including such factors as reduced system complexity, better operability, and lower costs. This paper reviews the status of a number of integrated flue-gas-cleanup systems that have reached a significant stage of development, focusing on post-combustion processes that have been tested or are ready for testing at the pilot scale or larger. A brief process description, a summary of the development status and performance achieved to date, pending commercialization issues, and process economics (when available) are given for each technology.

  2. SO{sub 2} and NO{sub x} control technologies - developments at Penn State`s Combustion Laboratory

    SciTech Connect

    Pisupati, S.V.

    1996-12-31

    The majority of pollution from coal combustion is from the emission of sulfur and nitrogen oxides. The Clean Air Act Amendments of 1990 established the Acid Rain Program under Title IV to achieve significant environmental and public health benefits through reductions in electric utility emissions of SO{sub 2} and NO{sub x}. The Act calls for significant reduction in NO{sub x} emissions by year 2000. The data obtained by EPA showed that 1995 SO{sub 2} emissions declined sharply by approximately 5 million tons below 1980 levels at the 445 Phase I affected electric utilities. The data also indicated that the boilers involved in the first stage of the NO{sub x} reduction program met Phase I emission standards of 0.5 lbs/MMBtu for dry bottom, wall fired units, and 0.45 lbs/MMBtu for tangentially fired boilers. Fluidized bed combustors, due to inherently low operating temperatures, produce less thermal NO{sub x} than pulverized coal units. However, with Ozone Transport Commission`s deliberations, it is expected that NO{sub x} emission limits could be lowered even further up to 0.15 lb/MMBtu for the fluidized bed combustion Units. Therefore, NO{sub x} reduction is important not only from an acid rain point of view but also from ozone formation at lower altitudes.

  3. Effect of SO/sub 2/ on light modulation of plant metabolism. Progress report

    SciTech Connect

    Anderson, L.E.

    1985-01-01

    This progress report briefly notes conclusions of work done on SO/sub 2/ effect on light modulation of plant metabolism. Conclusions include: effect of light activation on kinetic parameters of fructosebisphosphatase - for this enzyme K/sub m/ decreases and V/sub max/ increases as a result of light activation; and the effect of sulfite and arsenite on light activation in 2 Pisum cultivars - the differences in sensitivity to SO/sub 2/ is directly reflected in differences in a thylakoid bound factor (LEM) to SO/sub 2/.

  4. SO{sub 2} trading program as a metaphor for a competitive electric industry

    SciTech Connect

    O`Connor, P.R.

    1996-12-31

    This very brief presentation focuses on the competitive market impacts of sulfur dioxide SO{sub 2} emissions trading. Key points of the presentation are highlighted in four tables. The main principles and results of the emissions trading program are outlined, and the implications of SO{sub 2} trading for the electric industry are listed. Parallels between SO{sub 2} trading and electric utility restructing identified include no market distortion by avoiding serious disadvantages to competitors, and avoidance of stranded costs through compliance flexibility. 4 tabs.

  5. Ambient air monitoring plan for Ciudad Acuna and Piedra Negras, Coahuila, Mexico. Final report

    SciTech Connect

    Winberry, J.; Henning, L.; Crume, R.

    1998-01-01

    The Cities of Ciudad Acuna and Piedras Negras and the State of Coahuila in Mexico are interested in improving ambient air quality monitoring capabilities in the two cities through the establishment of a network of ambient air monitors. The purpose of the network is to characterize population exposure to potentially harmful air contaminants, possibly including sulfur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), ozone (O{sub 3}), carbon monoxide (CO), total suspended particulate matter (TSP), particulate matter with aerodynamic diameter less than 100 micrometers PM-10, and lead. This report presents the results of an evaluation of existing air quality monitoring equipment and facilities in Ciudad Acuna and Piedras Negras. Additionally, the report presents recommendations for developing an air quality monitoring network for PM-10, SO{sub 2}, lead, and ozone in these cities, using a combination of both new and existing equipment. The human resources currently available and ultimately needed to operate and maintain the network are also discussed.

  6. Use of pyrolyzed carbon black as an additive (part 3. Air-cooled furnace slag). Final report

    SciTech Connect

    Lee, K.H.; Lovell, C.W.; Salgado, R.

    1996-11-20

    Scrap tires, generated at the rate of over 242 million each year in the United States, are recognized as one of the most significant environmental problems. Most of these scrap tires have been disposed of in landfills, stockpiles, and illegal dumps (EPA 1991). There is a need to find more useful, environmentally friendly applications for these tires. Extensive researches have been conducted in the past years on the utilization of the scrap tires. The use of scrap tires for asphalt pavement, which is complicated by the complex behavior of asphalt, has received major attention. This research aims to describe the performance of mixtures of asphalt using pyrolyzed carbon black as an additive.

  7. High SO{sub 2} removal efficiency testing. Technical progress report, [1 April--30 June 1993

    SciTech Connect

    Blythe, G.

    1993-07-15

    On the base program, testing was completed at the Tampa Electric Big Bend Station in November, 1992. The upgrade option tested was DBA additive. Project efforts primarily consisted of project management activities and reporting. Review comments were received for the draft Technical Note that was submitted last quarter. A paper was prepared summarizing results from this site for presentation at the 1993 SO{sub 2} Control Symposium which is planned for August. For Option 1, at the Hoosier Energy Merom Station, results from another program co-funded by the Electric Power Research Institute (EPRI) and the National Rural Electric Cooperative Association are being combined with results from DOE-funded testing. Three upgrade options have been tested: DBA additive, sodium formate additive, and high pH set point operation. All testing was completed by November, 1992. Project efforts during the current quarter were primarily in data reduction and reporting. The draft Technical Note for the Merom site was submitted in early April, and review comments were received in late May and early June. Option 2 involves testing at the Southwestern Electric Power Company Pirkey Station. For this option, baseline testing was conducted in February. The upgrade option scheduled to be tested at this site was sodium formate additive. However, based on interim results from other sites and feedback from the Technology Working Group for this project, it was decided to test both sodium formate and DBA additive at Pirkey. Parametric testing with DBA additive was conducted in March, and parametric testing with sodium formate was conducted in April. Based on the initial results from the parametric test series, DBA appeared to be the more attractive upgrade option for this site. Consequently, a DBA additive consumption test was conducted in May. Option 3 and 4 are discussed briefly.

  8. Advanced in-duct sorbent injection for SO{sub 2} control. Topical report No. 2, Subtask 2.2: Design optimization

    SciTech Connect

    Rosenhoover, W.A.; Stouffer, M.R.; Withum, J.A.

    1994-12-01

    The objective of this research project is to develop second-generation duct injection technology as a cost-effective SO{sub 2} control option for the 1990 Clean Air Act Amendments. Research is focused on the Advanced Coolside process, which has shown the potential for achieving the performance targets of 90% SO{sub 2} removal and 60% sorbent utilization. In Subtask 2.2, Design Optimization, process improvement was sought by optimizing sorbent recycle and by optimizing process equipment for reduced cost. The pilot plant recycle testing showed that 90% SO{sub 2} removal could be achieved at sorbent utilizations up to 75%. This testing also showed that the Advanced Coolside process has the potential to achieve very high removal efficiency (90 to greater than 99%). Two alternative contactor designs were developed, tested and optimized through pilot plant testing; the improved designs will reduce process costs significantly, while maintaining operability and performance essential to the process. Also, sorbent recycle handling equipment was optimized to reduce cost.

  9. High SO{sub 2} removal efficiency testing. Technical progress report

    SciTech Connect

    Blythe, G.

    1994-04-28

    The project involves testing at six full-scale utility flue gas desulfurization (FGD) systems, to evaluate low capital cost upgrades that may allow these systems to achieve up to 98% SO{sub 2} removal efficiency. The upgrades to be evaluated mostly involve using additives in the FGD systems. On the base program, testing was completed at the Tampa Electric Big Bend Station in November 1992. The upgrade option tested was DBA additive. For Option 1, at the Hoosier Energy Merom Station, three upgrade options have been tested: DBA additive, sodium formate additive, and high pH set point operation. Option 2 has involved testing at the Southwestern Electric Power Company Pirkey Station. Both sodium formate and DBA additives were tested as potential upgrade options at Pirkey. On Option 3, for testing at the PSI Energy Gibson Station, a DBA additive performance and consumption test was conducted in late February through mid-March 1994. Preliminary results from these tests are discussed in Section 3 of this progress report. Option 4 is for testing at the Duquesne Light Elrama Station. The FGD system employs magnesium-enhanced lime reagent and venturi absorber modules. An EPRI-funded model evaluation of potential upgrade options for this FGD system, along with a preliminary economic evaluation, determined that the most attractive upgrade options for this site were to increase thiosulfate ion concentrations in the FGD system liquor to lower oxidation percentages and increase liquid-phase sulfite alkalinity, and to increase the venturi absorber pressure drop to improve gas/liquid contacting. Parametric testing of these upgrade options was conducted in late March 1994. Preliminary results from these tests are also discussed in Section 3 of this progress report.

  10. Effect of fly ash addition on the removal of hydrogen sulfide from biogas and air on sewage sludge-based composite adsorbents.

    PubMed

    Seredych, Mykola; Strydom, Christien; Bandosz, Teresa J

    2008-01-01

    Desulfurization adsorbents were prepared from the mixtures of various compositions of New York City sewage sludge and fly ashes from SASOL, South Africa, by pyrolysis at 950 degrees C. The resulting materials were used as adsorbents of hydrogen sulfide from simulated dry digester gas mixture or moist air. The adsorbents before and after H(2)S removal were characterized using adsorption of nitrogen, elemental analysis, pH measurements, XRF, XRD, and thermal analysis. It was found that the addition of fly ash decreases the desulfurization capacity in comparison with the sewage sludge-based materials. The extent of this decrease depends on the type of ash, its content and the composition of challenging gas. Although the presence of CO(2) deactivates some adsorption sites to various degrees depending on the sample composition, the addition of ashes has a more detrimental effect when the adsorbents are used to remove hydrogen sulfide from air. This is likely the result of hydrophobicity of ashes since the H(2)S removal capacity was found to be strongly dependent on the reactivity towards water/water adsorption. On the other hand, the addition of ashes strongly decreases the porosity of materials where sulfur, as a product of hydrogen sulfide oxidation, can be stored. PMID:17935967

  11. Fog chamber studies of soot-catalyzed SO/sub 2/ oxidation

    SciTech Connect

    Benner, W.H.; Brodzinsky, R.; Novakov, T.

    1980-11-01

    The oxidation of SO/sub 2/ by wet soot particles has been suggested as an important reaction pathway for the production of particulate sulfate in the ambient atmosphere. We studied this reaction in two systems. The first consisted of a flask-type reaction study. H/sub 2/SO/sub 3/ (diluted final concentration between 7 x 10/sup -8/ M and 1 x 10/sup -3/ M) was added to a flask containing several hundred milliliters of a constantly stirred aqueous suspension of Nuchar-SN in which the soot particle concentration was between 0.002 and 0.32% w/v carbon. For H/sub 2/SO/sub 3/ concentrations less than 10/sup -4/ M, sulfite and sulfate were determined by ion chromatography. Above 10/sup -4/ M H/sub 2/SO/sub 3/, sulfite concentration was determined by iodometric titrations while sulfate was measured turbidometrically only in selected runs. The pH of a soot suspension was controlled by the buffering capacity of the SO/sub 2/.H/sub 2/O, HSO/sub 3//sup -/, SO/sub 3//sup =/ system.

  12. Statistical time-series analysis of emission and deposition of SO{sub 2} and NO{sub x} in northeastern North America

    SciTech Connect

    Mariam, Y.K.G.; Barre, M.

    1997-12-31

    Trend analysis and forecasting of time series data on air-pollutants is important to design effective measures to minimize damages to ecosystems and human health. In this study, autoregressive, moving average, autoregressive-moving average and autoregressive integrated moving average processes of different order were implemented to examine patterns of depositions and emissions. Analysis was undertaken to examine stationary of the series or to design a method to create stationary series. The model that satisfied selected statistical criteria was chosen to make forecasts. Forecasts of depositions were compared with critical loads by watersheds. The findings of this study indicated that both wet depositions and emissions of SO{sub 2} and NO{sub x} data exhibited non-stationary. After removing non-stationary, a suitable time-series model was selected for short-run forecasting. The resulting depositions and emissions data were examined with respect to their long-run movement and critical deposition loadings. The analysis showed that excess wet depositions of SO{sub 2} and NO{sub 3} would be major problems at least for ten years. Most of these problems are observed in Atlantic Canada and few watersheds in Quebec and Ontario. Although emissions of SO{sub 2} have declined, emissions of NO{sub x} remained unchanged or increased compared to the 1980 level. Considering the fact that these pollutants contribute to acidification, eutrophication and formation of secondary particulates that are hazardous to human health, it is necessary to find ways of further reducing emissions and depositions of these pollutants. While substantial progress has been made with respect to reduction of SO{sub 2} emissions (especially in Canada), the analysis presented in this study indicated that there must be substantially more reductions to ensure the protection of sensitive ecosystems.

  13. Crystal structure and properties of [OsO{sub 2}(NH{sub 3}){sub 4}]SO{sub 4} . H{sub 2}O

    SciTech Connect

    Burvikova, J. N. Lin'ko, I. V.; Venskovskiy, N. U.; Rybakov, V. B.

    2007-03-15

    The structure of a single crystal of tetraammindioxoosmium(VI) sulfate [OsO{sub 2}(NH{sub 3}){sub 4}]SO{sub 4} . H{sub 2}O, which is synthesized by the reaction of K{sub 2}[OsO{sub 2}(OH){sub 4}] with (NH{sub 4}){sub 2}SO{sub 4} in an aqueous solution, is investigated using X-ray diffraction analysis. The compound crystallizes in the monoclinic crystal system, space group P2{sub 1}/c, a = 13.102(2) A, b = 6.158(3) A, c = 11.866(2) A, {beta} = 98.13(2) deg., and Z = 4. The [OsO{sub 2}(NH{sub 3}){sub 4}]SO{sub 4} . H{sub 2}O compound has an island structure. Two crystallographically independent osmium atoms are situated at the centers of symmetry, and their octahedral coordination includes two oxygen atoms and four nitrogen atoms of the ammonia molecules. In both octahedra, the osmyl group is linear. The Os-O distances in the octahedra are identical within the standard deviations [Os(1)-O, 1.762(2) A; Os(2)-O, 1.769(2) A]. The Os-N bond lengths vary from 2.082(3) to 2.101(3) A. The cationic complexes, SO{sub 4} groups, and water molecules are linked via the system of hydrogen bonds. The assignment of the absorption bands in the IR spectrum of the compound synthesized is performed, and its thermal behavior in air is studied.

  14. Evaluation of AA5052 alloy anode in alkaline electrolyte with organic rare-earth complex additives for aluminium-air batteries

    NASA Astrophysics Data System (ADS)

    Wang, Dapeng; Li, Heshun; Liu, Jie; Zhang, Daquan; Gao, Lixin; Tong, Lin

    2015-10-01

    Behaviours of the AA5052 aluminium alloy anode of the alkaline aluminium-air battery are studied by the hydrogen evolution test, the electrochemical measurements and the surface analysis method. The combination of amino-acid and rare earth as electrolyte additives effectively retards the self-corrosion of AA5052 aluminium alloy in 4 M NaOH solution. It shows that the combination of L-cysteine and cerium nitrate has a synergistic effect owing to the formation of a complex film on AA5052 alloy surface. The organic rare-earth complex can decrease the anodic polarisation, suppress the hydrogen evolution and increase the anodic utilization rate.

  15. Simultaneous removal of SO{sub 2} and NO from flue gas using 'oxygen-enriched' highly reactive absorbent

    SciTech Connect

    Zhao, Y.; Sun, X.J.; Fang, H.; Liu, F.

    2007-04-15

    Fly ash, industry-grade lime, and an additive, MnO{sub 2} (M), were used to prepare an 'oxygen-enriched' highly reactive absorbent. Experiments of simultaneous desulfurization and denitrification were carried in a flue gas circulating fluidized bed (CFB). The effects of influencing factors were also investigated on the removal efficiencies of desulfurization and denitrification. Removal efficiencies of 95.5% for SO{sub 2} and 64.8% for NO were obtained respectively under the optimal experimental conditions. The component of the spent absorbent was analyzed with chemical analysis methods. The results indicated that more nitrogen species appeared in the spent absorbent except sulfur species. A scanning electron microscope (SEM) and an accessory X-ray energy spectrometer (EDS) were used to observe microproperties of the samples, including fly ash, oxidizing highly reactive absorbent, and spent absorbent. The simultaneous removal mechanism of SO{sub 2} and NO based on this absorbent was proposed according to the experimental results.

  16. Simultaneous removal of NO and SO{sub 2} by high-temperature fluidized zero-valent iron processes

    SciTech Connect

    Shiao-Shing Chen; Chih-Yu Cheng; Chung-Cheng Wei; Chao-Heng Tseng

    2007-03-15

    A new approach to simultaneously remove nitrogen monoxide (NO) and sulfur dioxide (SO{sub 2}) by zero valent iron (ZVI) was investigated. Three different parameters, temperature, flux, and ZVI dosage, were tested in fluidized ZVI column studies containing 500 ppmv of NO and SO{sub 2}, respectively. Under the ZVI dosage of 0.5 g at flux of 0.6 L/cm{sub 2} min for temperature 573 K, there is neither NO nor SO{sub 2} reduction. For 623 K and 673 K, complete removal for NO and 90% removal for SO{sub 2} were achieved. For temperatures of 723 K and 773 K, 100% removal was achieved for both NO and SO{sub 2}. The amounts of NO or SO{sub 2} reduction increased as temperature increased, and linearities were observed with both correlation coefficients 0.97. Compared with NO, SO{sub 2} had earlier breakthrough because of a slower diffusion rate and less reactivity but higher mass reduction because of a higher molecular weight for SO{sub 2}. At the same temperature, both NO and SO{sub 2} reductions were constant regardless of either flux or ZVI dosage variation, but breakthrough time was affected by both flux and ZVI dosage. A parameter weight of ZVI/flux (W/F) was developed to represent these two parameters and assess the breakthrough time of NO and SO{sub 2}. Higher breakthrough time was achieved for higher W/F value. Longer breakthrough time and more NO and SO{sub 2} mass reduction were achieved for combined NO and SO{sub 2} than individual NO or SO{sub 2} treated by ZVI, and both oxidation and reduction reactions occurred. 15 refs., 8 figs., 1 tab.

  17. Estimation of the CO{sub 2} absorption capacities in aqueous 2-(2-aminoethylamino)ethanol and its blends with MDEA and TEA in the presence of SO{sub 2}

    SciTech Connect

    Bonenfant, D.; Minleault, M.; Hausler, R.

    2007-12-15

    A study of carbon dioxide (CO{sub 2}) and sulfur dioxide (SO{sub 2})/CO{sub 2} mixtures absorption has been carried out in aqueous 2-(2-aminoethylamino)ethanol (AEE) solution and its blends with N-methyldiethanolamine (MDEA) and triethanolamine (TEA) to estimate the influence of SO{sub 2}, MDEA, and TEA on the CO{sub 2} absorption capacity of the AEE. The CO{sub 2} absorption loading has been estimated in 15 wt % AEE alone and in the presence of either 5 and 10 wt % MDEA or 5 and 10 wt % TEA solutions with 100 vol % CO{sub 2} and 5.03 and 15.02 vol % SO{sub 2}/CO{sub 2} mixtures at a starting temperature of 296 K and flow rates of 3.067, 3.229, and 3.605 L/min, respectively. The results revealed that the presence of SO{sub 2} in the gas decreases the CO{sub 2} absorption rate and loading in the AEE solution as a function of the concentration of SO{sub 2}. The additions of 5 and 10 wt % of MDEA and TEA do not seem to influence the CO{sub 2} absorption rate in the AEE solution. Moreover, the addition of MDEA increases slightly the CO{sub 2} absorption capacity of AEE, while TEA decreases the absorption capacity of AEE in the absence and presence Of SO{sub 2}. These effects were enhanced with increases of MDEA and TEA. Altogether, the results indicated that the blend of 15 wt % AEE + 10 wt % MDEA represents an interesting solvent which could be used as absorbent for the removal of CO{sub 2} from emission into the atmosphere by industries.

  18. The crystal structure of Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O and its decomposition product, {beta}-Yb{sub 2}(SO{sub 4}){sub 3}

    SciTech Connect

    Mills, Stuart J.; Petricek, Vaclav; Kampf, Anthony R.; Herbst-Imer, Regine; Raudsepp, Mati

    2011-09-15

    Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O, synthesised by hydrothermal methods at 220(2) deg. C, has been investigated by single crystal X-ray diffraction. Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O crystallises in space group Cmc2{sub 1} and is isostructural with Lu{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O. The crystal structure has been refined to R{sub 1}=0.0145 for 3412 reflections [F{sub o}>3{sigma}(F)], and 0.0150 for all 3472 reflections. The structure of Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O is a complex framework of YbO{sub 6} octahedra, YbO{sub 8} and YbO{sub 5}(H{sub 2}O){sub 3} polyhedra and SO{sub 4} tetrahedra. Thermal data shows that Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O decomposes between 120 and 190 deg. C to form {beta}-Yb{sub 2}(SO{sub 4}){sub 3}. The structure of a twinned crystal of {beta}-Yb{sub 2}(SO{sub 4}){sub 3} was solved and refined using an amplimode refinement in R3c with an R{sub 1}=0.0755 for 8944 reflections [F{sub o}>3{sigma}(F)], and 0.1483 for all 16,361 reflections. {beta}-Yb{sub 2}(SO{sub 4}){sub 3} has a unique structural topology based on a 3D network of pinwheels. - Graphical abstract: Octahedral-tetrahedral linkages found in Y{sub 2}(SO{sub 4}){sub 3} [and Er{sub 2}(SO{sub 4}){sub 3}] and ss-Yb{sub 2}(SO{sub 4}){sub 3}. Highlights: > The crystal structure and decomposition reactions of Yb{sub 2}(SO{sub 4}){sub 3}.3H{sub 2}O. > The crystal structure of a twinned crystal of {beta}-Yb{sub 2}(SO{sub 4}){sub 3}. > Comparison of the structures of {beta}-Yb{sub 2}(SO{sub 4}){sub 3} and Y{sub 2}(SO{sub 4}){sub 3}.

  19. Effects of O{sub 2} and SO{sub 2} on the Capture Capacity of a Primary-Amine Based Polymeric CO{sub 2} Sorbent

    SciTech Connect

    Hallenbeck, Alexander P; Kitchin, John R

    2013-08-01

    Post combustion CO{sub 2} capture is most commonly carried out using an amine solution that results in a high parasitic energy cost in the stripper unit due to the need to heat the water which comprises a majority of the amine solution. It is also well known that amine solvents suffer from stability issues due to amine leaching and poisoning by flue gas impurities. Solid sorbents provide an alternative to solvent systems that would potentially reduce the energy penalty of carbon capture. However, the cost of using a particular sorbent is greatly affected by the usable lifetime of the sorbent. This work investigated the stability of a primary amine-functionalized ion exchange resin in the presence of O{sub 2} and SO{sub 2}, both of which are constituents of flue gas that have been shown to cause degradation of various amines in solvent processes. The CO{sub 2} capture capacity was measured over multiple capture cycles under continuous exposure to two simulated flue gas streams, one containing 12 vol% CO{sub 2}, 4% O{sub 2}, 84% N{sub 2}, and the other containing 12.5 vol% CO{sub 2}, 4% O{sub 2}, 431 ppm SO{sub 2}, balance N{sub 2} using a custom-built packed bed reactor. The resin maintained its CO{sub 2} capture capacity of 1.31 mol/kg over 17 capture cycles in the presence of O{sub 2} without SO{sub 2}. However, the CO{sub 2} capture capacity of the resin decreased rapidly under exposure to SO{sub 2} by an amount of 1.3 mol/kg over 9 capture cycles. Elemental analysis revealed the resin adsorbed 1.0 mol/kg of SO{sub 2}. Thermal regeneration was determined to not be possible. The poisoned resin was, however, partially regenerated with exposure to 1.5M NaOH for 3 days resulting in a 43% removal of sulfur, determined through elemental analysis, and a 35% recovery of CO{sub 2} capture capacity. Evidence was also found for amine loss upon prolonged (7 days) continuous exposure to high temperatures (120 C) in air. It is concluded that desulfurization of the flue gas

  20. A facile preparation and the luminescent properties of Eu{sup 3+}-doped Y{sub 2}O{sub 2}SO{sub 4} nanopieces

    SciTech Connect

    Song, Lixin; Shao, Xiaoli; Du, Pingfan; Cao, Houbao; Hui, Quan; Xing, Tonghai; Xiong, Jie

    2013-11-15

    Graphical abstract: - Highlights: • Y{sub 2}O{sub 2}SO{sub 4}:Eu{sup 3+} nanopieces were prepared via electrospinning followed by calcination. • The photoluminescence of Y{sub 2}O{sub 2}SO{sub 4}:Eu{sup 3+} nanopieces were investigated. • The Y{sub 2}O{sub 2}SO{sub 4}:Eu{sup 3+} was compared to nanoribbons and commercial Y{sub 2}O{sub 3}:Eu{sup 3+}. • The potential applications of the nanopieces and the facile method are suggested. - Abstract: The europium(III)-doped yttrium oxysulfate (Y{sub 2}O{sub 2}SO{sub 4}:Eu{sup 3+}) nanopieces have been prepared via electrospinning followed by calcination at 1000 °C in mixed gas of sulfur dioxide and air. Based on the experimental results, a possible formation mechanism for the nanopieces is that the nanopieces are determined by the directing template of electrospun nanoribbons and the multilayer crystal structure of Y{sub 2}O{sub 2}SO{sub 4}. Besides, the nanopieces show excellent luminescent properties with emissions at 581, 589, 597, 653, 619, and 697 nm resulting from the {sup 5}D{sub 0} → {sup 7}F{sub J} (J = 0, 1, 2, 3, 4) transition of Eu{sup 3+}. The peaks of charge transfer and {sup 5}D{sub 0} → {sup 7}F{sub 2} transition of Eu{sup 3+} obviously have red shifts comparing to those of both Y{sub 2}O{sub 3}:Eu{sup 3+} nanoribbons and commercial Y{sub 2}O{sub 3}:Eu{sup 3+}. Moreover, the nanopieces exhibit stronger intensities than the Y{sub 2}O{sub 3}:Eu{sup 3+} in excitation and emission spectra. Concentration quenching in the nanopieces occurs when Eu{sup 3+} concentration is 11 mol%, indicating that the nanopieces have an optimum luminescent intensity under this doping concentration.

  1. Effect of controlled low levels of SO/sub 2/ on grasshopper densities on a northern mixed-grass prairie

    SciTech Connect

    McNary, T.J.; Milchunas, D.G.; Leetham, J.W.; Lauenroth, W.K.; Dodd, J.L.

    1981-02-01

    A northern mixed-grass prairie was exposed to monthly median SO/sub 2/ concentrations of 73, 134, and 228 ..mu..g/m/sup 3/. Total grasshopper density and the density of Melanoplus sanguinipes (F.) were significantly (P < 0.01) reduced by SO/sub 2/ treatment on late-growing-season dates within each year of SO/sub 2/ exposure. Grasshopper density tended to decrease with increasing SO/sub 2/ concentration. Sulfur dioxide did not alter the relative proportions of M. sanguinipes in the total population. 14 references, 1 figure.

  2. Recent trends in SO{sub 2} allowance marketplace

    SciTech Connect

    Bartels, C.W.

    1997-12-31

    The author reviews the development of the marketplace for tradable allowances created under Title IV of the Clean Air Act Amendments (CAAA) of 1990. The major characteristics exhibited by today`s market are traced to the key factors affecting market development. The author concludes that the market has finally reached a level of early maturity, implying a more systematic approach to trading.

  3. Influence of operation conditions and additives on the development of producer gas and tar reduction in air gasification of construction woody wastes using a two-stage gasifier.

    PubMed

    Mun, Tae-Young; Kim, Jin-O; Kim, Jin-Won; Kim, Joo-Sik

    2011-07-01

    Air gasification was conducted with fractions of construction woody wastes in a two-stage gasifier, consisting of a fluidized bed zone and a tar cracking zone. The aim of this work is to investigate the influence of reaction conditions and additives on the composition of producer gas and tar content in producer gas. A producer gas obtained with activated carbon of 540 g at an ER of 0.26 was mainly composed of H(2) (25 vol.%), CO (22 vol.%) and CH(4) (5 vol.%). Regarding tar removal efficiency, activated carbon was better than olivine. The tar removal rate with virgin activated carbon reached up to 80%. The reuse of spent activated carbon caused an efficiency loss in tar removal to some extent. Overall, it seems that the strong need for intensive downstream tar removal measurements can be removed with the use of a two-stage gasifier and the application of activated carbon. PMID:21565495

  4. Addition of equilibrium air to an upwind Navier-Stokes code and other first steps toward a more generalized flow solver

    NASA Technical Reports Server (NTRS)

    Rosen, Bruce S.

    1991-01-01

    An upwind three-dimensional volume Navier-Stokes code is modified to facilitate modeling of complex geometries and flow fields represented by proposed National Aerospace Plane concepts. Code enhancements include an equilibrium air model, a generalized equilibrium gas model and several schemes to simplify treatment of complex geometric configurations. The code is also restructured for inclusion of an arbitrary number of independent and dependent variables. This latter capability is intended for eventual use to incorporate nonequilibrium/chemistry gas models, more sophisticated turbulence and transition models, or other physical phenomena which will require inclusion of additional variables and/or governing equations. Comparisons of computed results with experimental data and results obtained using other methods are presented for code validation purposes. Good correlation is obtained for all of the test cases considered, indicating the success of the current effort.

  5. DOE seeks low-cost, retrofit SO/sub 2/ control method

    SciTech Connect

    Not Available

    1985-10-01

    DOE is funding the development by four companies of a low-cost way to lower sulfur dioxide SO/sub 2/ emissions from power plants to be ready in case emission controls are required. The program seeks methods for removing 50-70% of SO/sub 2/ for less than $500 per ton. Conventional scrubbers remove 90% at $800-$2000 per ton. The approach is to inject reagents into the flue gas stream behind the boiler. One approach, the HALT method, adds hydrated lime at low temperature and collects solid calcium sulfate in the precipitator with the fly ash. With a goal of 80% removal, HALT is ready for demonstration. Other efforts include lime injection and in-duct spray drying techniques using atomized lime slurries. The TUNG process produces salable liquid SO/sub 2/, sulfuric acid, or elemental sulfur and reduces steam costs, but requires a separate scrubbing vessel.

  6. SO/sub 2/ dose-response sensitivity classification data for crops and natural vegetation species

    SciTech Connect

    Irving, P.M.; Ballou, S.W.

    1980-09-01

    Over the past several years studies have been made on the interaction of sulfur dioxide (SO/sub 2/) and vegetation by performing field research and by developing analytical procedures for applying field observation data to energy impact assessments. As a result of this work, numerous reports have been prepared on crop-pollutant interactions, such as dose-response data; on the applications of such data to screening approaches for identifying crops at risk; and on models that predict crop yield reductions from point source emissions of SO/sub 2/. Data that were used for these studies, such as the crop-at-risk screening procedure, are presented in this report. Maps are also presented that show the national distribution of SO/sub 2/-sensitive crops and natural vegetation.

  7. High temperature membranes for H[sub 2]S and SO[sub 2] separations

    SciTech Connect

    Winnick, J.

    1992-01-01

    High temperature membrane separation techniques have been applied to gas mixtures involved in coal utilization. For coal gasification, H[sub 2]S has been removed from the syn-gas stream, split into hydrogen which enriches the syn-gas, and sulfur which can be condensed from an inert gas sweep stream. For coal combustion, SO[sub 2] has been separated from the flue gas, with concentrated SO[sub 3] produced as a by-product. Both processes appear economically viable but each requires fundamental improvements: both the H[sub 2]S cell and the SO[sub 2] cell require more efficient membranes and the H[sub 2]S cell needs a more efficient anode. Membranes will be fabricated by either hot-pressing, impregnation of sintered bodies, or tape casting. Research conducted during the present quarter is highlighted, with an emphasis on progress towards these goals.

  8. Lessons learned from the use of portable samplers in an air quality monitoring network within a developing country

    SciTech Connect

    Baldauf, R.W.; Bareta, M.J.; Sithole, J.

    1997-12-31

    International monetary institutions and government environmental agencies increasingly require the collection of ambient air quality data in developing countries. These data may be used to evaluate the construction of new or modified industrial facilities, determine long-term air pollution trends in urbanized areas, or analyze the effectiveness of air pollution control programs for stationary and mobile sources. Several factors can inhibit or prevent the efficient collection of air pollution data including the high initial cost and long lead times required to install air monitoring systems, the availability of trained personnel to operate and maintain the equipment, the availability of established laboratory facilities for conducting the chemical and gravimetric analyses, and the accessibility of a reliable power source at the monitoring site(s). An air quality monitoring network using portable samplers was established in the vicinity of a coal fired power plant in Zimbabwe to measure inhalable particulate matter (PM{sub 10}), nitrogen oxide (NO{sub x}), and sulfur dioxide (SO{sub 2}) pollutant concentrations. These samplers included battery-operated monitors for PM{sub 10} measurements and passive sampling devices for NO{sub x} and SO{sub 2} measurements. Portable samplers were chosen over traditional, continuous ambient air quality analyzers based on lower capital, operational, and maintenance costs; the minimal technical expertise required to operate and maintain the equipment; and the siting flexibility associated with no requirement for an external source of power. In addition, the use of portable air samplers allowed for a rapid deployment of the monitoring network due to the short procurement and installation times required. This paper discusses the benefits, limitations, and obstacles experienced during the use of portable air quality samplers for one year of ambient air quality monitoring in Zimbabwe.

  9. Volcanic output of SO/sub 2/ and trace metals: a new approach

    SciTech Connect

    Lambert, G.; le Cloarec, M.; Pennisi, M.

    1988-01-01

    Owing to a model of volcanic emission of gases and volatiles, it was possible to normalize to /sup 210/Po the volcanic output of SO/sub 2/, Pb, Bi and other trace as well as major metals. It appears that the results concerning SO/sub 2/, Pb and Bi agree with previous estimates derived on a very different basis. The evaluation was extended to Cd, Cu, Zn, Al, Mg, Na and K. Moreover, it was observed that, even for poorly volatile major metals, the part of volcanic aerosols produced by evaporation is at least comparable to that which results from spattering.

  10. 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.

  11. FY 1994 ambient air monitoring report for McMurdo Station, Antarctica

    SciTech Connect

    Lugar, R.M.

    1994-12-01

    This report presents the results of ambient air monitoring performed during the 1994 fiscal year (FY 1994) in the vicinity of McMurdo Station, Antarctica. Routine monitoring was performed during the 1993-1994 austral summer at three locations for airborne particulate matter less than 10 micrometers (PM-10) and at two locations for carbon monoxide (CO), sulfur dioxide (SO{sub 2}), and nitrogen oxides (NO, NO{sub 2}, and NO{sub x}). Selected PM-10 filters were analyzed for arsenic, beryllium, cadmium, chromium, lead, mercury, and nickel. Additional air samples were collected at three McMurdo area locations and at Black Island for determination of the airborne concentration of polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). Sampling site selection, sampling procedures, and quality assurance procedures used were consistent with US Environmental Protection Agency guidance for local ambient air quality networks.

  12. The effect of palladium additions on the solidus/liquidus temperatures and wetting properties of Ag-CuO based air brazes

    SciTech Connect

    Darsell, Jens T.; Weil, K. Scott

    2007-01-01

    A new ceramic brazing technique referred to as reactive air brazing (RAB) has recently been developed for potential applications in high temperature devices such as gas concentrators, solid oxide fuel cells, gas turbines, and combustion engines. At present, the technique utilizing a silver-copper oxide system is of great interest. The maximum operating temperature of this system is limited by its eutectic temperature of ~945°C, although in practice the operating temperature will need to be lower. An obvious strategy that can be employed to increase the maximum operating temperature of the braze material is to add a higher melting noble alloying element. In this paper, we report the effects of palladium addition on the melting characteristics of the Ag-CuO system and on the wetting properties of the resulting braze with respect to alumina. It was found that the addition of Pd will cause an increase in the melting temperature of the Ag-CuO braze but possibly at a sacrifice of wetting properties depending on composition.

  13. Thermal decomposition behavior of the rare-earth ammonium sulfate R{sub 2}(SO{sub 4}){sub 3}.(NH{sub 4}){sub 2}SO{sub 4}

    SciTech Connect

    Nagai, Tsukasa; Tamura, Shinji; Imanaka, Nobuhito

    2010-07-15

    Rare-earth ammonium sulfate octahydrates of R{sub 2}(SO{sub 4}){sub 3}.(NH{sub 4}){sub 2}SO{sub 4}.8H{sub 2}O (R=Pr, Nd, Sm, and Eu) were synthesized by a wet process, and the stable temperature region for the anhydrous R{sub 2}(SO{sub 4}){sub 3}.(NH{sub 4}){sub 2}SO{sub 4} form was clarified by thermogravimetry/differential thermal analysis, infrared, Raman, and electrical conductivity measurements. Detailed characterization of these double salts demonstrated that the thermal stability of anhydrous R{sub 2}(SO{sub 4}){sub 3}.(NH{sub 4}){sub 2}SO{sub 4} is different between the Pr, Nd salts and the Sm, Eu salts, and the thermal decomposition behavior of these salts was quite different from the previous reports. - Graphical abstract: Stable temperature range of anhydrous rare-earth ammonium sulfate R{sub 2}(SO{sub 4}){sub 3}.(NH{sub 4}){sub 2}SO{sub 4} was clarified by thermogravimetry/differential thermal analysis, infrared, Raman, and electrical conductivity measurements. Since the previous reports were based only on thermal analysis, the present work has more accurately determined the exact thermal stability of rare-earth ammonium sulfate solids.

  14. Modeling the effects of changes in New Source Review on national SO{sub 2} and NOx emissions from electricity-generating units

    SciTech Connect

    David A. Evans; Benjamin F. Hobbs; Craig Oren; Karen L. Palmer

    2007-03-15

    The Clean Air Act establishes New Source Review (NSR) programs that apply to the construction or modification of major stationary emissions sources. In 2002 and 2003, the U.S. Environmental Protection Agency revised its rules to narrow the applicability of NSR to facility renovations. Congress then mandated a National Research Council study of the effects of the rules. An electricity-sector model - the Integrated Planning Model (IPM) - was used to explore the possible effects of the equipment replacement provision (ERP), the principal NSR change that was to affect the power-generation industry. The studies focused in particular on coal-fired electricity generating units, EGUs, for two reasons. First, coal-fired EGUs are important contributors of these pollutants, accounting for approximately 70 and 20% of nations SO{sub 2} and NOx emissions in 2004, respectively. Second, the shares of total capacity of large coal-fired EGUs that lack flue-gas desulfurization to control SO{sub 2} and selective catalytic reduction to reduce NOx emissions are 62 and 63% respectively. Although the analysis cannot predict effects on local emissions, assuming that the Clean Air Interstate Rule (CAIR) is implemented, we find that stringent enforcement of the previous NSR rules would likely lead to no or limited decreases in national emissions compared to policies such as ERP. Our results indicate that tighter emissions caps could achieve further decreases in national emissions more cost-effectively than NSR programs. 15 refs., 3 figs., 1 tab.

  15. Synthesis and optical properties of (Gd{sub 1-x},Eu{sub x}){sub 2}O{sub 2}SO{sub 4} nano-phosphors by a novel co-precipitation method

    SciTech Connect

    Lian Jingbao; Sun Xudong; Liu Zhigang; Yu Jingyuan; Li Xiaodong

    2009-09-15

    (Gd{sub 1-x},Eu{sub x}){sub 2}O{sub 2}SO{sub 4} nano-phosphors were synthesized by a novel co-precipitation method from commercially available Gd{sub 2}O{sub 3}, Eu{sub 2}O{sub 3}, H{sub 2}SO{sub 4} and NaOH starting materials. Composition of the precursor is greatly influenced by the molar ratio of NaOH to (Gd{sub 1-x},Eu{sub x}){sub 2}(SO{sub 4}){sub 3} (the m value), and the optimal m value was found to be 4. Fourier transform infrared spectrum (FT-IR) and thermal analysis show that the precursor (m = 4) can be transformed into pure (Gd{sub 1-x},Eu{sub x}){sub 2}O{sub 2}SO{sub 4} nano-phosphor by calcining at 900 deg. C for 2 h in air. Transmission electron microscope (TEM) observation shows that the Gd{sub 2}O{sub 2}SO{sub 4} phosphor particles (m = 4) are quasi-spherical in shape and well dispersed, with a mean particle size of about 30-50 nm. Photoluminescence (PL) spectroscopy reveals that the strongest emission peak is located at 617 nm under 271 nm light excitation, which corresponds to the {sup 5}D{sub 0} {yields} {sup 7}F{sub 2} transition of Eu{sup 3+} ions. The quenching concentration of Eu{sup 3+} ions is 10 mol% and the concentration quenching mechanism is exchange interaction among the Eu{sup 3+} ions. Decay study reveals that the {sup 5}D{sub 0} {yields} {sup 7}F{sub 2} transition of Eu{sup 3+} ions has a single exponential decay behavior.

  16. Effect on SO/sub 2/ light modulation of plant metabolism. Final progress report, June 1, 1983-May 31, 1985

    SciTech Connect

    Anderson, L.E.

    1985-01-01

    The effect of sulfite and arsenite on light activation in two pisum cultivars was examined. The experiments indicate that the difference in sensitivity to SO/sub 2/ is directly reflected in sensitivity of a thylakoid bound factor to SO/sub 2/. 2 figs. (DT)

  17. OH-Radical Specific Addition to Glutathione S-Atom at the Air-Water Interface: Relevance to the Redox Balance of the Lung Epithelial Lining Fluid.

    PubMed

    Enami, Shinichi; Hoffmann, Michael R; Colussi, Agustín J

    2015-10-01

    Antioxidants in epithelial lining fluids (ELF) prevent inhaled air pollutants from reaching lung tissue. This process, however, may upset ELF's redox balance, which is deemed to be expressed by the ratio of the major antioxidant glutathione (GSH) to its putative oxidation product GSSG. Previously, we found that at physiological pH O3(g) rapidly oxidizes GS(2-)(aq) (but not GSH(-)) to GSO3(-) rather than GSSG. Here, we report that in moderately acidic pH ≤ 5 media ·OH(g) oxidizes GSH(-)(aq) to sulfenic GSOH(-), sulfinic GSO2(-), and sulfonic GSO3(-) acids via ·OH specific additions to reduced S-atoms. The remarkable specificity of ·OH on water versus its lack of selectivity in bulk water implicates an unprecedented steering process during [OH···GSH] interfacial encounters. Thus, both O3 and ·OH oxidize GSH to GSOH(-) under most conditions, and since GSOH(-) is reduced back to GSH in vivo by NADPH, redox balance may be in fact signaled by GSH/GSOH ratios. PMID:26722895

  18. Application of the deletion/substitution/addition algorithm to selecting land use regression models for interpolating air pollution measurements in California

    NASA Astrophysics Data System (ADS)

    Beckerman, Bernardo S.; Jerrett, Michael; Martin, Randall V.; van Donkelaar, Aaron; Ross, Zev; Burnett, Richard T.

    2013-10-01

    Land use regression (LUR) models are widely employed in health studies to characterize chronic exposure to air pollution. The LUR is essentially an interpolation technique that employs the pollutant of interest as the dependent variable with proximate land use, traffic, and physical environmental variables used as independent predictors. Two major limitations with this method have not been addressed: (1) variable selection in the model building process, and (2) dealing with unbalanced repeated measures. In this paper, we address these issues with a modeling framework that implements the deletion/substitution/addition (DSA) machine learning algorithm that uses a generalized linear model to average over unbalanced temporal observations. Models were derived for fine particulate matter with aerodynamic diameter of 2.5 microns or less (PM2.5) and nitrogen dioxide (NO2) using monthly observations. We used 4119 observations at 108 sites and 15,301 observations at 138 sites for PM2.5 and NO2, respectively. We derived models with good predictive capacity (cross-validated-R2 values were 0.65 and 0.71 for PM2.5 and NO2, respectively). By addressing these two shortcomings in current approaches to LUR modeling, we have developed a framework that minimizes arbitrary decisions during the model selection process. We have also demonstrated how to integrate temporally unbalanced data in a theoretically sound manner. These developments could have widespread applicability for future LUR modeling efforts.

  19. Associations between criteria air pollutants and asthma

    SciTech Connect

    Koren, H.S.

    1995-09-01

    The evidence that asthma is increasing in prevalence is becoming increasingly compelling. This trend has been demonstrated in the United States, the United Kingdom, New Zealand, Australia, and several other Western countries. In the US, the increase is largest in the group under 18 years of age. There is mounting evidence that certain environmental air pollutants are involved in exacerbating asthma. This is based primarily on epidemiologic studies and more recent clinical studies. The U.S. Clean Air Act of 1970 provides special consideration to the class of outdoor air pollutants referred to as criteria pollutants, including O{sub 3}, sulfur dioxide (SO{sub 2}), particulate matter (PM), NO{sub x}, CO, and Pb. Standards for these pollutants are set by the US EPA with particular concern for populations at risk. Current evidence suggests that asthmatics are more sensitive to the effects of O{sub 3}, SO{sub 2} PM, and NO{sub 2}, and are therefore at risk. High SO{sub 2} and particulate concentrations have been associated with short-term increases in morbidity and mortality in the general population during dramatic air pollution episodes in the past. Controlled exposure studies have clearly shown that asthmatics are sensitive to low levels of SO{sub 2}. Exercising asthmatics exposed to SO{sub 2} develop bronchoconstriction within minutes, even at levels of 0.25 ppm. Responses are modified by air temperature, humidity, and exercise level. Recent epidemiologic studies have suggested that exposure to Pm is strongly associated with morbidity and mortality in the general population and that hospital admissions for bronchitis and asthma were associated with PM{sub 10} levels. In controlled clinical studies, asthmatics appear to be no more reactive to aerosols than healthy subjects. Consequently, it is difficult to attribute the increased mortality observed in epidemiologic studies to specific effects demonstrated in controlled human studies. 106 refs., 1 fig., 1 tab.

  20. Direct effects of energy-related air pollutants on plant sexual reproduction

    SciTech Connect

    Ragsdale, H.L.; Murdy, W.H.

    1987-12-08

    Our completed research program concentrated on the direct in vivo effects of energy-related air pollutants on plant sexual reproduction. Direct air pollution effects on plant sexual reproduction have been studied for SO{sub 2} and NO{sub 2}, two of the three major air pollutants.

  1. Effect of addition of planetary milled Gd-211 on the microstructures and superconducting properties of air-processed single grain Gd-Ba-Cu-O/Ag bulk superconductors

    NASA Astrophysics Data System (ADS)

    Iida, K.; Nenkov, K.; Fuchs, G.; Krabbes, G.; Holzapfel, B.; Büchner, B.; Schultz, L.

    2010-11-01

    Planetary milling technique has been a very promising way to obtain bulk superconductors with very high critical current density, Jc, albeit a detail characterisation of milled secondary phase precursor powders in particular has not been reported to date. Hence we report systematic studies of the effect of addition of planetary milled Gd2BaCuO5 (Gd-211) on the final microstructures and superconducting properties of air-processed Gd-Ba-Cu-O/Ag bulk samples. Average size of Gd-211 precursor particles, which were planetary milled with 1.0 mm ZrO2 beads, has been observed to decrease significantly from 1.03 μm to 0.52 μm with increasing milling duration. Besides the size distribution of milled Gd-211 was narrow compared to that of the reference powder. A small amount of Zr was detected, however, in the milled Gd-211 powder by the inductively coupled plasma-optical emission spectroscopy (ICP-OES) and its content was increased with increasing milling period, which led to an inhomogeneous bulk microstructure. Significantly, the average size of Gd-211 particles milled for 45 min has been observed to decrease from 0.73 μm to 0.48 μm without severe contamination of Zr when the diameter of the beads were reduced from 1.0 mm to 0.3 mm. Trapped magnetic field of single grain Gd-Ba-Cu-O/Ag bulk sample with 32 mm in diameter prepared from almost Zr free Gd-211 fine particles recorded over 1.5 T at 77 K, which was almost 1.3 times greater than that of the reference sample. Nevertheless the repulsive force of both bulk samples showed around 57 N at a gap of zero between the sample surface and SmCo5 permanent magnet.

  2. Determining the CH{sub 3}SO{sub 2}{yields}CH{sub 3}+SO{sub 2} barrier from methylsulfonyl chloride photodissociation at 193 nm using velocity map imaging

    SciTech Connect

    Ratliff, Britni J.; Tang Xiaonan; Butler, Laurie J.; Szpunar, David E.; Lau, Kai-Chung

    2009-07-28

    These imaging experiments study the formation of the methylsulfonyl radical, CH{sub 3}SO{sub 2}, from the photodissociation of CH{sub 3}SO{sub 2}Cl at 193 nm and determine the energetic barrier for the radical's subsequent dissociation to CH{sub 3}+SO{sub 2}. We first state-selectively detect the angular and recoil velocity distributions of the Cl({sup 2}P{sub 3/2}) and Cl({sup 2}P{sub 1/2}) atoms to further refine the distribution of internal energy partitioned to the momentum-matched CH{sub 3}SO{sub 2} radicals. The internal energy distribution of the radicals is bimodal, indicating that CH{sub 3}SO{sub 2} is formed in both the ground state and low-lying excited electronic states. All electronically excited CH{sub 3}SO{sub 2} radicals dissociate, while those formed in the ground electronic state have an internal energy distribution which spans the dissociation barrier to CH{sub 3}+SO{sub 2}. We detect the recoil velocities of the energetically stable methylsulfonyl radicals with 118 nm photoionization. Comparison of the total recoil translational energy distribution for all radicals to the distribution obtained from the detection of stable radicals yields an onset for dissociation at a translational energy of 70{+-}2 kcal/mol. This onset allows us to derive a CH{sub 3}SO{sub 2}{yields}CH{sub 3}+SO{sub 2} barrier height of 14{+-}2 kcal/mol; this determination relies on the S-Cl bond dissociation energy, taken here as the CCSD(T) predicted energy of 65.6 kcal/mol. With 118 nm photoionization, we also detect the velocity distribution of the CH{sub 3} radicals produced in this experiment. Using the velocity distributions of the SO{sub 2} products from the dissociation of CH{sub 3}SO{sub 2} to CH{sub 3}+SO{sub 2} presented in the following paper, we show that our fastest detected methyl radicals are not from these radical dissociation channels, but rather from a primary S-CH{sub 3} bond photofission channel in CH{sub 3}SO{sub 2}Cl. We also present critical points on

  3. Development of advanced, dry, SO{sub x}/NO{sub x} emission control technologies for high-sulfur coal. Final report, April 1, 1993--December 31, 1994

    SciTech Connect

    Amrhein, G.T.

    1994-12-23

    Dry Scrubbing is a common commercial process that has been limited to low- and medium-sulfur coal applications because high-sulfur coal requires more reagent than can be efficiently injected into the process. Babcock & Wilcox has made several advances that extend dry scrubbing technologies to higher sulfur coals by allowing deposit-free operation at low scrubber exit temperatures. This not only increases the amount of reagent that can be injected into the scrubber, but also increases SO{sub 2} removal efficiency and sorbent utilization. The objectives of this project were to demonstrate, at pilot scale, that advanced, dry-scrubbing-based technologies can attain the performance levels specified by the 1990 Clean Air Act Amendments for SO{sub 2} and NO{sub x} emissions while burning high-sulfur coal, and that these technologies are economically competitive with wet scrubber systems. The use of these technologies by utilities in and around Ohio, on new or retrofit applications, will ensure the future of markets for high-sulfur coal by creating cost effective options to coal switching.

  4. Control of coal combustion SO{sub 2} and NO{sub x} emissions by in-boiler injection of CMA. Final project report, July 1, 1992--December 31, 1994

    SciTech Connect

    Levendis, Y.A.

    1995-04-01

    A study was conducted to determine the efficacy of carboxylic calcium and magnesium salts (e.g., calcium magnesium acetate or CMA, CaMg{sub 2}(CH{sub 2}COOH){sub 6}) for the simultaneous removal of SO{sub 2} and NO{sub x} in oxygen-lean atmospheres. Experiments were performed in a high-temperature furnace that simulated the post-flame environment of a coal-fired boiler by providing similar temperatures and partial pressures of SO{sub 2}, NO{sub x} CO{sub 2} and O{sub 2}. When injected into a hot environment, the salts calcined and formed highly porous {open_quotes}popcorn{close_quotes}-like cenospheres. Residual MgO and/or CaCO{sub 3} and CaO reacted heterogeneously with SO{sub 2} to form MgSO{sub 4} and/or CaCO{sub 4}. The organic components - which can be manufactured from wastes such as sewage sludge - gasified and reduced NO{sub x }to N{sub 2} efficiently if the atmosphere was moderately fuel-rich. Dry-injected CMA particles at a Ca/S ratio of 2, residence time of 1 second and bulk equivalence ratio of 1.3 removed over 90% of SO{sub 2} and NO{sub x} at gas temperatures {>=} 950{degrees}C. When the furnace isothermal zone was {<=} 950{degrees}C, Ca was essentially inert in the furnace quenching zone, while Mg continued to sorb SO{sub 2} as the gas temperature cooled at a rate of -130{degrees}C/sec. Hence, the removal of SO{sub 2} by CMA could continue for nearly the entire residence time of emissions in the exhaust stream of a power plant. Additional research is needed to improve the efficiency and reduce the cost of the relatively expensive carboxylic acid salts as dual SO{sub 2}-NO{sub x} reduction agents. For example, wet injection of the salts could be combined with less expensive hydrocarbons such as lignite or even polymers such as poly(ethylene) that could be extracted from the municipal waste stream.

  5. A simultaneous SO{sub x} and NO{sub x} removal system for burning all grades of coal

    SciTech Connect

    Frank, N.W.; Maezawa, A.

    1995-12-31

    Burning coal for cooking, heating, industrial uses and for electricity generation is nothing new and has been around for centuries. With the recent advent of global environmental awareness the method of burning and cleaning up the gases from boilers has come under scrutiny by regulatory agencies and even the general public. Throughout history basically premium coals were used for combustion, but as regulations got more strict, the work premium has constantly changed. There was a time when soot was the most common complaint about coal combustion, but as devices such as cyclones, electrostatic precipitators and baghouses appeared, that problem was solved. However, the unseen elements in gases were being studied and identified and regulations began to appear for SO{sub 2}, NO{sub X} and other air toxins. Unfortunately mother nature did not give us only one grade of coal which is perfect, so mankind had to look for ways to improve the burning and cleanup so that the earths most economical and abundant fuel supply could be used with efficiency and cleanliness.

  6. Application of calcium chloride as an additive for secondary refrigerant in the air conditioning system type chiller to minimized energy consumption

    NASA Astrophysics Data System (ADS)

    Suwono, A.; Indartono, Y. S.; Irsyad, M.; Al-Afkar, I. C.

    2015-09-01

    One way to resolve the energy problem is to increase the efficiency of energy use. Air conditioning system is one of the equipment that needs to be considered, because it is the biggest energy user in commercial building sector. Research currently developing is the use of phase change materials (PCM) as thermal energy storage (TES) in the air conditioning system to reduce energy consumption. Salt hydrates have been great potential to be developed because they have been high latent heat and thermal conductivity. This study has used a salt hydrate from calcium chloride to be tested in air conditioning systems type chiller. Thermal characteristics were examined using temperature history (T-history) test and differential scanning calorimetry (DSC). The test results showed that the thermal characteristics of the salt hydrate has been a high latent heat and in accordance with the evaporator temperature. The use of salt hydrates in air conditioning system type chiller can reduce energy consumption by 51.5%.

  7. Superposition-additive approach in the description of thermodynamic parameters of formation and clusterization of substituted alkanes at the air/water interface.

    PubMed

    Vysotsky, Yu B; Belyaeva, E A; Fomina, E S; Vasylyev, A O; Vollhardt, D; Fainerman, V B; Aksenenko, E V; Miller, R

    2012-12-01

    The superposition-additive approach developed previously was shown to be applicable for the calculations of the thermodynamic parameters of formation and atomization of conjugate systems, their dipole polarizability, molecular diamagnetic susceptibility, π-electronic ring currents, etc. In the present work, the applicability of this approach for the calculation of the thermodynamic parameters of formation and clusterization at the water/air interface of alkanes, fatty alcohols, thioalcohols, amines, nitriles, fatty acids (C(n)H(2n+1)X, X is the functional group) and cis-unsaturated carboxylic acids (C(n)H(2n-1)COOH) is studied. Using the proposed approach the thermodynamic quantities determined agree well with the available data, either calculated using the semiempirical (PM3) quantum chemical method, or obtained in experiments. In particular, for enthalpy and Gibbs' energy of the formation of substituted alkane monomers from the elementary substances, and their absolute entropy, the standard deviations of the values calculated according to the superposition-additive scheme with the mutual superimposition domain C(n-2)H(2n-4) (n is the number of carbon atoms in the alkyl chain) from the results of PM3 calculations for alkanes, alcohols, thioalcohols, amines, fatty acids, nitriles and cis-unsaturated carboxylic acids are respectively: 0.05, 0.004, 2.87, 0.02, 0.01, 0.77, and 0.01 kJ/mol for enthalpy; 2.32, 5.26, 4.49, 0.53, 1.22, 1.02, 5.30 J/(molK) for absolute entropy; 0.69, 1.56, 3.82, 0.15, 0.37, 0.69, 1.58 kJ/mol for Gibbs' energy, whereas the deviations from the experimental data are: 0.52, 5.75, 1.40, 1.00, 4.86 kJ/mol; 0.52, 0.63, 1.40, 6.11, 2.21 J/(molK); 2.52, 5.76, 1.58, 1.78, 4.86 kJ/mol, respectively (for nitriles and cis-unsaturated carboxylic acids experimental data are not available). The proposed approach provides also quite accurate estimates of enthalpy, entropy and Gibbs' energy of boiling and melting, critical temperatures and standard heat

  8. Catalysts for the reduction of SO{sub 2} to elemental sulfur

    SciTech Connect

    Jin, Y.; Yu, Q.Q.; Chang, S.G.

    1995-11-01

    Catalysts have been prepared for the reduction of SO{sub 2} to elemental sulfur by synthesis gas. A catalyst allows to obtain more than 97% yield of elemental sulfur with a single-stage reactor at 540{degrees}C. A lifetime test has been successfully performed. The mass balance of sulfur and carbon has been checked. The effect of H{sub 2}S, COS, and H{sub 2}O has been studied.

  9. Hollow fiber contractors for simultaneous SO{sub x}/NO{sub x} removal

    SciTech Connect

    Bhown, A.S.; Pakala, N.R.; Riggs, T.

    1995-11-01

    Control of SO{sub x} and NO{sub x} emissions from coal-fired utility and industrial boilers is a topic of growing national and international importance. Whereas a host of commercial and semicommercial processes exist, increasingly stringent emission standards mandate that processes be low cost, highly efficient, and, ideally, produce marketable byproducts. Although a wide range of site-specific economic factors dictate the best choice of SO{sub x} and NO{sub x} control, removal of SO{sub 2} by wet limestone scrubbing and removal of NO{sub x} by selective catalytic reduction (SCR) are regarded as the best commercialized technologies for this application. A typical wet limestone plant requires approximately $100 to $120 of capital investment per kilowatt of electric power generating capacity and has power and miscellaneous operating costs in the range of 5 to 6 mils per kilowatt hour (kWh). The SCR process requires approximately $70 to $100 of capital investment per kilowatt of electric power generating capacity. Its operating costs, including ammonia consumption, is in the range of 1.8 to 2.2 mils per kWh. These costs can add approximately 20% to the final cost of generated electricity, a significant burden on rate payers.

  10. New form of calcium carbonate improves SO{sub 2} removal from boilers

    SciTech Connect

    1996-11-01

    As acid rain control regulations take effect, some utility companies are considering or have installed flue gas desulfurization (FGD) systems using lime-based sorbents. With one type of FGD system, called furnace sorbent injection (FSI), sorbents are injected directly into the combustion chamber of a coal-fired boiler. Such systems have proven effective at reducing sulfur dioxide (SO{sub 2}) emissions from some types of boilers, especially those that operate at relatively low temperatures. However, FSI systems have generally not performed well with most types of conventional boilers. A New York company has patented a new FGD sorbent called thermally active marble (TAM). TAMs tend to fracture and expose new reaction surfaces - much like ice cubes in hot water. This enables such materials to neutralize SO{sub 2} more efficiently and at much higher temperatures than limestone. In fact, TAMs have shown the ability to neutralize SO{sub 2} even when injected into the hottest portion of many conventional boilers. TAMs have also been shown to reduce nitrogen oxide (NO{sub x}) formation and improve boiler efficiency by promoting more complete carbon combustion. Pilot- and full-scale tests of TAMs in several types of boilers are described in this paper. 3 refs., 1 fig., 1 tab.

  11. Catalytic reduction of SO{sub 2} with methane over molybdenum catalyst. Quarterly report, 1 December 1994--28 February 1995

    SciTech Connect

    Wiltowski, T.

    1995-12-31

    One of the primary concerns in coal utilization is the emission of sulfur compounds, especially SO{sub 2}. This project deals with catalytic reduction of SO{sub 2} with methane using molybdenum sulfide catalyst supported on different activated carbons: Darco TRS, Norit ROZ-3, and an activated carbon prepared from Illinois coal IBC-110. The work conducted during this quarter has concentrated on continuation of the synthesis of activated carbon derived from Illinois coal IBC-110, modification and improvement of the apparatus for the catalyst testing, ESCA (XPS) analysis of the catalyst (10% MoS{sub 2} on Darco TRS activated carbon), and experiments in the temperature range of 450{degree}C--600{degree}C for the S0{sub 2}:CH{sub 4} ratio equal 1:1. XPS study confirmed that Mo is present in the form of Mo+4 and S in the form of S-2. The catalytic experiments of SO{sub 2} reduction with CH{sub 4} showed that for both Darco TRS and ROZ-3 supports, S0{sub 2} conversion increases with the temperature. Also, the catalyst having 20% loading of MoS{sub 2} on Darco TRS support shows the highest S0{sub 2} conversion over 10% or 15% loadings on Darco TRS. In contrast, for the ROZ-3 support, the catalyst having a 15% loading shows the highest activity. Additionally, it was observed that conversions of S0{sub 2} at 600{degree}C for both supports are comparable to each other when catalysts with 20% loadings are used; at lower temperatures, the activities are quite different with the conversions being higher for Darco TRS support.

  12. Effects of SO/sub 2/ on growth and yield of winter crops grown in California. Research report (Final) November 1983-February 1985

    SciTech Connect

    Thompson, C.R.

    1985-09-01

    The objective of the study was to ascertain the sensitivity of wheat and lettuce to SO/sub 2/ or ambient oxidants when plants are exposed under California winter conditions, the season when these crops are normally grown in California. The study was conducted in open top field chambers at the University of California, Riverside. Wheat was exposed to SO/sub 2/ or ambient oxidants for 118 days. Lettuce was exposed to SO/sub 2/ or ambient oxidants for 47 days. SO/sub 2/ at 183 and 393 micrograms/m/sup 3/ produced chlorotic injury on wheat leaves and increased total leaf sulfur. At 79 micrograms/m/sup 3/, SO/sub 2/ reduced wheat leaf buffering capacity. SO/sub 2/ at 393 micrograms/m/sup 3/ reduced total wheat seed weight by 31%. Lettuce showed no detrimental effect from SO/sub 2/.

  13. Effect of SO/sub 2/ on the clearance of Listeria monocytogenes from the lungs of emphysematous hamsters

    SciTech Connect

    Trimpe, K.L.; Weiss, H.; Zwilling, B.S.

    1986-10-01

    The effect of sulfur dioxide on the clearance of Listeria monocytogenes from normal and emphysematous hamsters was assessed by measuring the number of colony forming units recovered from whole lung homogenates. Continuous exposure to SO/sub 2/ after intratracheal instillation of Listeria significantly altered the clearance of viable bacteria from the lungs of emphysematous but not normal hamsters. Pre-exposure of hamsters to SO/sub 2/ for 2 weeks prior to respiratory infection had similar effects. The emphysematous hamsters exposed to SO/sub 2/ had a lower average number of Listeria in the lungs after the first week of infection than control groups. This effect appears to result from the combined influence of the SO/sub 2/, the Listeria infection, and the emphysematous condition within the lungs.

  14. Process for simultaneous removal of SO[sub 2] and NO[sub x] from gas streams

    DOEpatents

    Rosenberg, H.S.

    1987-02-03

    A process is described for simultaneous removal of SO[sub 2] and NO[sub x] from a gas stream that includes flowing the gas stream to a spray dryer and absorbing a portion of the SO[sub 2] content of the gas stream and a portion of the NO[sub x] content of the gas stream with ZnO by contacting the gas stream with a spray of an aqueous ZnO slurry; controlling the gas outlet temperature of the spray dryer to within the range of about a 0 to 125 F approach to the adiabatic saturation temperature; flowing the gas, unreacted ZnO and absorbed SO[sub 2] and NO[sub x] from the spray dryer to a fabric filter and collecting any solids therein and absorbing a portion of the SO[sub 2] remaining in the gas stream and a portion of the NO[sub x] remaining in the gas stream with ZnO; and controlling the ZnO content of the aqueous slurry so that sufficient unreacted ZnO is present in the solids collected in the fabric filter to react with SO[sub 2] and NO[sub x] as the gas passes through the fabric filter whereby the overall feed ratio of ZnO to SO[sub 2] plus NO[sub x] is about 1.0 to 4.0 moles of ZnO per of SO[sub 2] and about 0.5 to 2.0 moles of ZnO per mole of NO[sub x]. Particulates may be removed from the gas stream prior to treatment in the spray dryer. The process further allows regeneration of ZnO that has reacted to absorb SO[sub 2] and NO[sub x] from the gas stream and acid recovery. 4 figs.

  15. Process for simultaneous removal of SO.sub.2 and NO.sub.x from gas streams

    DOEpatents

    Rosenberg, Harvey S.

    1987-01-01

    A process for simultaneous removal of SO.sub.2 and NO.sub.x from a gas stream that includes flowing the gas stream to a spray dryer and absorbing a portion of the SO.sub.2 content of the gas stream and a portion of the NO.sub.x content of the gas stream with ZnO by contacting the gas stream with a spray of an aqueous ZnO slurry; controlling the gas outlet temperature of the spray dryer to within the range of about a 0.degree. to 125.degree. F. approach to the adiabatic saturation temperature; flowing the gas, unreacted ZnO and absorbed SO.sub.2 and NO.sub.x from the spray dryer to a fabric filter and collecting any solids therein and absorbing a portion of the SO.sub.2 remaining in the gas stream and a portion of the NO.sub.x remaining in the gas stream with ZnO; and controlling the ZnO content of the aqueous slurry so that sufficient unreacted ZnO is present in the solids collected in the fabric filter to react with SO.sub.2 and NO.sub.x as the gas passes through the fabric filter whereby the overall feed ratio of ZnO to SO.sub.2 plus NO.sub.x is about 1.0 to 4.0 moles of ZnO per of SO.sub.2 and about 0.5 to 2.0 moles of ZnO per mole of NO.sub.x. Particulates may be removed from the gas stream prior to treatment in the spray dryer. The process further allows regeneration of ZnO that has reacted to absorb SO.sub.2 and NO.sub.x from the gas stream and acid recovery.

  16. Control of coal combustion SO{sub 2} and NO{sub x} emissions by in-boiler injection of CMA. Second quarterly project status report, 1 April 1993--30 June 1993

    SciTech Connect

    Levendis, Y.A.; Wise, D.L.

    1993-09-01

    Objectives of the proposed research are two-fold: (A) To understand the mechanism and assess the effectiveness of sulfur capture by the chemical calcium magnesium acetate (CMA); and (B) To evaluate the NO{sub x} reduction capabilities of CMA by pyrolyzing the organic constituents of the chemical (the acetate) and reducing NO to stable N{sub 2}. The optimum conditions and the location of CMA introduction in the furnace will be identified. Water solutions of CMA or dry powders of CMA will be injected into hot air or gases simulating the furnace exhaust (containing CO{sub 2}, SO{sub x} NO{sub x} H{sub 2}O, O{sub 2} etc.) and the composition of gaseous and solid products of the reaction will be monitored. The processes of burning the organic acetate as well as the calcination, sintering and sulfation of the remaining solid will be studied. The effectiveness of ``homemade`` CMAs containing various amounts of calcium and magnesium will be investigated to explore the role of the two chemicals in the NO{sub x} and mainly the SO{sub 2} capture processes. CMA will be introduced in the matrix of coal particles by an ion exchange technique. Upon subsequent combustion, the SO{sub 2}-NO{sub x} emissions will be monitored and compared to those from burning untreated coal. The composition and physical structure of the ash residues will also be examined.

  17. Control of coal combustion SO[sub 2] and NO[sub x] emissions by in-boiler injection of CMA

    SciTech Connect

    Levendis, Y.A.; Wise, D.L.

    1992-01-01

    The principal objectives of the proposed research are two-fold: (A) To understand the mechanism and assess the effectiveness of sulfur capture by the chemical calcium magnesium acetate (CMA). And (B) To evaluate the NO[sub x] reduction capabilities of CMA by burning the organic constituents of the chemical (the acetate) and reducing NO to stable N[sub 2] The optimum conditions and the location of CMA introduction in the furnace will be identified. To achieve these goals water solutions of CMA or dry powders of CMA will be injected into hot air or gases simulating the furnace exhaust (containing CO[sub 2], SO[sub x] NO[sub x], H[sub 2]O, O[sub 2] etc.) and the composition of gaseous and solid products of the reaction will be monitored. The processes of burning the organic acetate as well as the calcination, sintering and sulfation of the remaining solid will be studied in detail.

  18. Microbial reduction of SO{sub 2} and NO{sub x} as a means of by-product recovery/disposal from regenerable processes for the desulfurization of flue gas. Technical progress report, September 11, 1992--December 11, 1992

    SciTech Connect

    Sublette, K.L.

    1992-12-31

    With the continual increase in the utilization of high sulfur and high nitrogen containing fossil fuels, the release of airborne pollutants into the environment has become a critical problem. The fuel sulfur is converted to SO{sub 2} during combustion. Fuel nitrogen and a fraction of the nitrogen from the combustion air are converted to nitric oxide and nitrogen dioxide, NO{sub x}. For the past five years Combustion Engineering (now Asea Brown Boveri or ABB) and, since 1986, the University of Tulsa (TU) have been investigating the oxidation of H{sub 2}S by the facultatively anaerobic and autotrophic bacterium Thiobacillus denitrificans and have developed a process, concept for the microbial removal of H{sub 2}S from a gas stream the simultaneous removal of SO{sub 2} and NO by D. desulfuricans and T. denitrificans co-cultures and cultures-in-series was demonstrated. These systems could not be sustained due to NO inhibition of D. desulfuricans. However, a preliminary economic analysis has shown that microbial reduction of SO{sub 2} to H{sub 2}S with subsequent conversion to elemental sulfur by the Claus process is both technically and economically feasible if a less expensive carbon and/or energy source can be found. It has also been demonstrated that T. denitrificans can be grown anaerobically on NO(g) as a terminal electron acceptor with reduction to elemental nitrogen. Microbial reduction of NO{sub x} is a viable process concept for the disposal of concentrated streams of NO{sub x} as may be produced by certain regenerable processes for the removal of SO{sub 2} and NO{sub x} from flue gas.

  19. Regional emissions of air pollutants in China.

    SciTech Connect

    Streets, D. G.

    1998-10-05

    As part of the China-MAP program, sponsored by the US National Aeronautics and Space Administration, regional inventories of air pollutants emitted in China are being characterized, in order that the atmospheric chemistry over China can be more fully understood and the resulting ambient concentrations in Chinese cities and the deposition levels to Chinese ecosystems be determined with better confidence. In addition, the contributions of greenhouse gases from China and of acidic aerosols that counteract global warming are being quantified. This paper presents preliminary estimates of the emissions of some of the major air pollutants in China: sulfur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}), carbon monoxide (CO), and black carbon (C). Emissions are estimated for each of the 27 regions of China included in the RAINS-Asia simulation model and are subsequently distributed to a 1{degree} x 1{degree} grid using appropriate disaggregation factors. Emissions from all sectors of the Chinese economy are considered, including the combustion of biofuels in rural homes. Emissions from larger power plants are calculated individually and allocated to the grid accordingly. Data for the period 1990-1995 are being developed, as well as projections for the future under alternative assumptions about economic growth and environmental control.

  20. Direct effects of energy-related air pollutants on plant sexual reproduction. Final report, February 1, 1979--January 31, 1982

    SciTech Connect

    Ragsdale, H.L.; Murdy, W.H.

    1987-12-08

    Our completed research program concentrated on the direct in vivo effects of energy-related air pollutants on plant sexual reproduction. Direct air pollution effects on plant sexual reproduction have been studied for SO{sub 2} and NO{sub 2}, two of the three major air pollutants.

  1. Process for the combined removal of SO.sub.2 and NO.sub.x from flue gas

    DOEpatents

    Chang, Shih-Ger; Liu, David K.; Griffiths, Elizabeth A.; Littlejohn, David

    1988-01-01

    The present invention in one aspect relates to a process for the simultaneous removal of NO.sub.x and SO.sub.2 from a fluid stream comprising mixtures thereof and in another aspect relates to the separation, use and/or regeneration of various chemicals contaminated or spent in the process and which includes the steps of: (A) contacting the fluid stream at a temperature of between about 105.degree. and 180.degree. C. with a liquid aqueous slurry or solution comprising an effective amount of an iron chelate of an amino acid moiety having at least one --SH group; (B) separating the fluid stream from the particulates formed in step (A) comprising the chelate of the amino acid moiety and fly ash; (C) washing and separating the particulates of step (B) with an aqueous solution having a pH value of between about 5 to 8; (D) subsequently washing and separating the particulates of step (C) with a strongly acidic aqueous solution having a pH value of between about 1 to 3; (E) washing and separating the particulates of step (D) with an basic aqueous solution having a pH value of between about 9 to 12; (F) optionally adding additional amino acid moiety, iron (II) and alkali to the aqueous liquid from step (D) to produce an aqueous solution or slurry similar to that in step (A) having a pH value of between about 4 to 12; and (G) recycling the aqueous slurry of step (F) to the contacting zone of step (A). Steps (D) and (E) can be carried out in the reverse sequence, however the preferred order is (D) and then (E). In another preferred embodiment the present invention provides a process for the removal of NO.sub.x, SO.sub.2 and particulates from a fluid stream which includes the steps of (A) injecting into a reaction zone an aqueous solution itself comprising (i) an amino acid moiety selected from those described above; (ii) iron (II) ion; and (iii) an alkali, wherein the aqueous solution has a pH of between about 4 and 11; followed by solids separation and washing as is

  2. Interactions Between Energy Efficiency and Emission Trading Under the 1990 Clean Air Act Amendments

    SciTech Connect

    Hillsman, E L

    1994-01-01

    Title IV of the 1990 Clean Air Act Amendments (P.L. 101-549) requires electric utilities to reduce emissions of precursors of acid precipitation, specifically sulfur dioxide (SO{sub 2}) and oxides of nitrogen (NO{sub x}), starting at 261 generating units in 1995 and covering most fossil-fired units in 2000. The Amendments take a conventional command-and-control approach to reducing NO{sub x}, but they established a market-based regulatory system to reduce SO{sub 2}. Under this system, utilities that own fossil-fired power plants in the conterminous 48 states and the District of Columbia are granted the right, in the form of allowances, to emit a specified number of tons of SO{sub 2}. A utility that wants to do so may reduce emissions more than required by the number of allowances it receives and then either sell its excess allowances to other utilities or bank them for future use. Alternatively, it can buy additional allowances from other utilities who may wish to sell, and emit more than its original allocation would have permitted, provided that it holds enough allowances from some source to cover emissions. The research described here attempts to estimate how large these interacting effects might be and how they might affect the choices that utilities make when complying with Title IV of the Amendments. They do so using a model that was designed to estimate what options electric utilities might choose in complying with Title IV, and what effects compliance would have on electricity costs. The model assumes that the allowance trading system would work as smoothly as the economic theory on which the system is based. Actual compliance decisions announced to date have been somewhat different from what theory and the model project. They discuss some of the reasons for these differences and the likely effects these differences may have on the interaction between allowance trading and energy efficiency.

  3. Behavior of oxide scales on 2. 25Cr-1Mo steel during thermal cycling. I. Scales formed in oxygen and air

    SciTech Connect

    Christl, W.; Rahmel, A.; Schuetze, M.

    1989-02-01

    The acoustic-emission (AE) technique has been applied to study scale-damage processes during thermal cycling of a tube, preferentially between 600 and 300/degree/C in air, oxygen, and air + 0.5% SO/sub 2/. The AE measurements were accompanied by optical and electron-optical investigations on tube rings exposed to the same cycling conditions. During the first period of cycling, a scale rich in hematite is formed. It suffers compressive stresses during cooling. The result is a buckled multilayered scale with separated lamellae. The scaling rate is lower than under isothermal conditions. AE signals start after 175/degree/C cooling. After longer exposure times, the scale contains an increasing amount of magnetite and becomes more compact. The scaling rate increases and is comparable to that under isothermal conditions. AE signals are already observed after 50/degree/C cooling and are correlated with crack formation in the magnetite caused by tensile stresses there. The addition of SO/sub 2/ to air enhances the crack-healing process due to higher Fe diffusion in FeS. The scale is more compact.

  4. SOXAL combined SO{sub x}/NO{sub x} flue gas control demonstration. Quarterly report, October--December 1992

    SciTech Connect

    1993-02-16

    AQUATECH Systems a business unit of Allied-Signal Inc., proposes to demonstrate the technical viability and cost effectiveness of the SOXAL process a combined SO{sub x}/NO{sub x} control process on a 2--3 MW equivalent flue gas slip stream from Niagara Mohawk Power Corporation, Dunkirk Steam Station Boiler {number_sign}4, a coal fired boiler. The SOXAL process combines 90+% sulfur dioxide removal from the flue gas using a sodium based scrubbing solution and regeneration of the spent scrubbing liquor using AQUATECH Systems` proprietary bipolar membrane technology. This regeneration step recovers a stream of sulfur dioxide suitable for subsequent processing to salable sulfur or sulfuric acid. Additionally 90+% control of NO{sub x} gases can be achieved in combination with conventional urea/methanol injection of NO{sub 2} gas into the duct. The SOXAL process is applicable to both utility and industrial scale boilers using either high or low sulfur coal. The SOXAL Demonstration Program began September 10, 1991 and is approximately 22 months in duration.

  5. Catalytic reduction of SO{sub 2} with methane over molybdenum catalyst. Technical report, March 1--May 31, 1995

    SciTech Connect

    Wiltowski, T.

    1995-12-31

    One of the primary concerns in coal utilization is the emission of sulfur compounds, especially SO{sub 2}. This project deals with catalytic reduction of SO{sub 2} with methane using molybdenum sulfide catalyst supported on different activated carbons: Darco TRS, ROZ-3, and an activated carbon prepared from Illinois coal IBC-110. The work conducted during this quarter included preparation of activated carbons from Illinois coal, preparation of the catalysts on these supports, and experiments on SO{sub 2} reduction with methane at different feed ratio SO{sub 2}: CH{sub 4}. It was found that at the feed ratio 1:1, 10% MoS{sub 2} supported on Darco TRS catalyst has highest activity at low temperatures; at higher temperatures, the catalysts 15% and 20% MoS{sub 2} supported on Darco TRS exhibit high activity in both SO{sub 2} conversion (> 90%) and yield of elemental sulfur (97.4% for 20% MoS{sub 2} at 600 C). For catalyst supported on ROZ-3, this having 10% of MOS{sub 2} showed high activity in the reaction. To determine the effect of feed ratio on the reaction, the catalysts with 15% loading of MoS{sub 2} supported on Darco TRS and ROZ-3 were used. For catalyst supported on ROZ-3 activated carbon, the effect of feed ratio is dramatic, especially at the higher temperatures at which the conversion of SO{sub 2} increases more than twice when the feed contains excess of methane. For catalyst supported on Darco TRS activated carbons, there is practically no difference in SO{sub 2} conversion for feed ratios 1:1 and 1:2 (with respect for methane).

  6. Combined SO{sub 2} and NO{sub x} scrubbing process

    SciTech Connect

    Breault, R.W.; Bittenson, S.; Lani, B.

    1998-04-01

    A new wet scrubber process has been developed and undergone preliminary testing to verify the viability of a zero discharge system for SO{sub 2} and NO{sub x} removal. The process combines the Dravo ThioClear{reg_sign} process with Tecogen`s TecoLytic{trademark} process. The integration of these two technologies results a system that removes both SO{sub 2} and NO{sub x} while producing only salable byproducts. These by-products are wall board grade gypsum, magnesium hydroxide and up to 60 weight percent fertilizer grade calcium nitrate solution. Hence, a zero waste, zero discharge wet scrubber system is being demonstrated. The core of the integrated technology consists of two parts. The first part is the ThioClear process. In this process, a highly alkaline magnesium sulfite solution is used to capture the SO{sub 2} in a high velocity (greater than 15 ft/s with a nominal design of 25 ft/s) horizontal scrubber. Once captured, the sulfites are oxidized to sulfates in an oxidizing vessel. The effluent from the oxidizer is reacted with a magnesium-enhanced lime slurry to raise the pH to about 10.5. At this higher pH, 6 to Mg magnesium hydroxide precipitates and 80g or larger gypsum precipitates are formed. Subsequent product purification produces salable gypsum and magnesium hydroxide. The flue gas continues through the high velocity horizontal scrubber passing through the TecoLytic {trademark} section. In this section, high voltage is applied to produce highly reactive excited species. These species interact with the water vapor present to produce hydroxyl radicals while simultaneously oxidizing the NO to NO{sub 2}. The hydroxyl radicals rapidly oxidize the NO{sub 2} to nitric acid which is scrubbed in the second stage of the horizontal scrubber with a calcium nitrate - lime solution.

  7. Developments in SO{sub 3} decomposition for nuclear hydrogen production

    SciTech Connect

    Suppiah, Sam; Tan, G.; Deschenes, L.

    2007-07-01

    The Sulphur-Iodine (S-I) Cycle is considered to be one of the best thermochemical hydrogen production processes currently under development in many countries. While the Very High Temperature Reactors (VHTRs) are capable of satisfying the high temperature requirements of all the steps of this process, Canada's Supercritical Water Reactor (SCWR) can satisfy the temperature requirements of all but the catalytic SO{sub 3} decomposition step. However, AECL's direct electrically heated catalytic structures may be used for the decomposition with only a marginal lowering of the overall efficiency of the S-I process. An externally heated reactor system with a 25-mm diameter by 100-mm long section for catalyst loading has been set-up and a few blank tests (without any catalyst) have been conducted. Pt-TiO{sub 2} and Fe{sub 2}O{sub 3} catalysts on ceramic rings were tested to provide base-case results for comparison with catalysts to be tested with electro-resistive heating. The H{sub 2}SO{sub 4} thermal decomposition was carried out at around 475 deg. C and SO{sub 3} decomposition rates were determined over the range of 500 to 900 deg. C. While both catalysts were very active for the decomposition reaction at the higher end of the range, the Pt-TiO{sub 2} catalyst was active even at the 500 deg. C region with the Fe{sub 2}O{sub 3} catalyst being active only above 600 deg. C. (authors)

  8. DETECTING PLANETARY GEOCHEMICAL CYCLES ON EXOPLANETS: ATMOSPHERIC SIGNATURES AND THE CASE OF SO{sub 2}

    SciTech Connect

    Kaltenegger, L.; Sasselov, D.

    2010-01-10

    We study the spectrum of a planetary atmosphere to derive detectable features in low resolution of different global geochemical cycles on exoplanets-using the sulfur cycle as our example. We derive low-resolution detectable features for first generation space- and ground-based telescopes as a first step in comparative planetology. We assume that the surfaces and atmospheres of terrestrial exoplanets (Earth-like and super-Earths) will most often be dominated by a specific geochemical cycle. Here we concentrate on the sulfur cycle driven by outgassing of SO{sub 2} and H{sub 2}S followed by their transformation to other sulfur-bearing species, which is clearly distinguishable from the carbon cycle, which is driven by outgassing of CO{sub 2}. Due to increased volcanism, the sulfur cycle is potentially the dominant global geochemical cycle on dry super-Earths with active tectonics. We calculate planetary emission, reflection, and transmission spectrum from 0.4 mum to 40 mum with high and low resolution to assess detectable features using current and Archean Earth models with varying SO{sub 2} and H{sub 2}S concentrations to explore reducing and oxidizing habitable environments on rocky planets. We find specific spectral signatures that are observable with low resolution in a planetary atmosphere with high SO{sub 2} and H{sub 2}S concentration. Therefore, first generation space- and ground-based telescopes can test our understanding of geochemical cycles on rocky planets and potentially distinguish planetary environments dominated by the carbon and sulfur cycles.

  9. The synthesis and characterization of neptunium hydroxysulfate, Np(OH)/sub 2/SO/sub 4/

    SciTech Connect

    Wester, D.W.; Mulak, J.; Banks, R.; Carnall, W.T.

    1982-11-15

    Neptunium (IV) hydroxysulfate, Np(OH)/sub 2/SO/sub 4/, was synthesized using hydrothermal techniques. The X-ray powder diffraction pattern indicates that the compound is isomorphous with the Th(IV) and U(IV) analogs. Cell constants for the three compounds clearly show the effects of the actinide contraction. Visible and near-ir spectra are consistent with the presence of Np(IV) and are compared to spectra of Np(IV) in acidic solution. The ir spectrum contains bands which are assigned to the hydroxy and sulfate groups.

  10. Adsorption of H{sub 2}S and SO{sub 2} and Bigadic clinoptilolite

    SciTech Connect

    Sirkecioglu, A.; Altav, Y.; Erdem-Senatalar, A.

    1995-07-01

    H{sub 2}S and SO{sub 2} adsorption isotherms of Bigadic clinoptilolite and its Na-, K-, Ca- and H-enriched forms were determined in the 0 to 100 kPa range at 25{degrees}C by using a constant volume adsorption system. Langmuir, Freundlich, Dubinin-Radushkevich (D-R), and Dubinin-Astakhov (D-A) models were applied to the isotherm data. Higher adsorption capacities and a larger increase in the amount adsorbed at higher pressures were observed for SO{sub 2}, in agreement with its higher permanent dipole moment, resulting in stronger ion-dipole and dipole-dipole interactions for this molecule. The Ca-form exhibited a molecular sieving behavior for both gases, originating from the channel blockage caused by the cation locations in the sample. The highest capacities for both gases were obtained with the sample in its H-form, followed by the Na- and K-forms for SO{sub 2}, parallel to the decrease in the electronegativity and ionic potential and the increase in the polarizability of the cation. In the case of H{sub 2}S, the H-form was followed by the K-form, but the Na-form yielded very low adsorption capacities. Initial dissociative adsorption of H{sub 2}S on certain Na sites to yield SH and OH species is thought to contribute to a more effective blocking of the channels, which were already partially blocked in this sample. Of the isotherm models tested, the D-A model explained the variations in the data better than either the Freundlich or D-R models. For the cation-gas combinations with a lower extent of channel blockage though, the Langmuir model was somewhat more representative. Lower E and n values were obtained from the D-A model for H{sub 2}S on the Na-form, which may be related to the lower extent of micropore adsorption and to the presence of blocked, almost dead-end shorter channel segments in the sample. Pore volumes close to the theoretical value were estimated from the D-A parameters for SO{sub 2} adsorption.

  11. Bringing down the cost of SO{sub 2} and NOx removal

    SciTech Connect

    Kohan, S.M.; Rettig, T.W.; Torbov, T.S.; Gale, T.K.

    2008-10-15

    A twist of an old technique, flue gas recirculating, helps prevent slagging in the upper furnace and convective pass, according to pilot testing recently completed by APTECH CST and the South Research Institute. The technology, along with a companion technology for furnace sorbent and urea injection for SO{sub 2} and NOx control, could help owner/operators of smaller, older coal-fired plants meet emissions limits at a reasonable cost. The article reviews the details and results of initial pilot-scale testing. Results met all the company's expectations when testing Powder River Basin and Galatia coals. A full-scale project is planned for operation in 2009. 7 figs.

  12. SNRB{trademark} air toxics monitoring. Final report

    SciTech Connect

    Not Available

    1994-01-01

    Babcock & Wilcox (B&W) is currently conducting a project under the DOE`s Clean Coal Technology (CCT II) Program to demonstrate its SO{sub x}NO{sub x}-Rox Box{trademark} (SNRB{trademark}) process in a 5 MWe Field Demonstration Unit at Ohio Edison`s R. E. Burger Plant near Shadyside, Ohio. The objective of the SNRB{trademark} Air Toxics Monitoring Project was to provide data on SNRB{trademark} air toxics emissions control performance to B&W and to add to the DOE/EPRI/EPA data base by quantifying the flow rates of selected hazardous substances (or air toxics) in all of the major input and output streams of the SNRB{trademark} process as well as the power plant. Work under the project included the collection and analysis of representative samples of all major input and output streams of the SNRB{trademark} demonstration unit and the power plant, and the subsequent laboratory analysis of these samples to determine the partitioning of the hazardous substances between the various process streams. Material balances for selected air toxics were subsequently calculated around the SNRB{trademark} and host boiler systems, including the removal efficiencies across each of the major air pollution control devices. This report presents results of the SNRB{trademark} Air Toxics Monitoring Project. In addition to the Introduction, a brief description of the test site, including the Boiler No. 8 and the SNRB{trademark} process, is included in Section H. The concentrations of air toxic emissions are presented in Section II according to compound class. Material balances are included in Section IV for three major systems: boiler, electrostatic precipitator, and SNRB{trademark}. Emission factors and removal efficiencies are also presented according to compound class in Sections V and VI, respectively. A data evaluation is provided in Section VII.

  13. Effect of air annealing on the color center in Yb:Y3Al5O12 transparent ceramics with MgO as sintering additive

    NASA Astrophysics Data System (ADS)

    Lu, Zhongwen; Lu, Tiecheng; Wei, Nian; Zhang, Wei; Ma, Benyuan; Qi, Jianqi; Guan, Yongbing; Chen, Xingtao; Wu, Huajun; Zhao, Yu

    2015-09-01

    High quality Yb:Y3Al5O12 (YAG) transparent ceramics were fabricated by vacuum sintering with MgO as sintering aids. The Yb:YAG samples were annealed at 1250-1450 °C for 20 h in air. The experimental results showed that the transparency of Yb:YAG samples declined markedly with the annealing temperatures of 1250-1450 °C. The samples became increasingly orange-yellow in color with the increase of annealing temperature. The potential reasons of discoloration were discussed for the first time. It was attributed to the complex color center [Mg2+F+] formed during the annealing, which was evidenced by optical absorption in the range of 300-500 nm wavelength and the presence of an electron spin resonance (ESR) line at g = 1.9806. The formation mechanism of the complex color center was explained in detail. The complex color center can be eliminated after post-HIP (hot isostatic pressing). And by air annealing and post-HIP, the transmittance of the samples increased from 80.3% to 83.4%.

  14. The addition of ortho-hexagon nano spinel Co3O4 to improve the performance of activated carbon air cathode microbial fuel cell.

    PubMed

    Ge, Baochao; Li, Kexun; Fu, Zhou; Pu, Liangtao; Zhang, Xi

    2015-11-01

    Commercial Co3O4 and ortho-hexagon spinel nano-Co3O4 (OHSNC) were doped in the AC at a different percentage (5%, 10% and 15%) to enhance the performance of microbial fuel cell (MFC). The maximum power density of MFC with 10% OHSNC doped cathode was 1500±14 mW m(-2), which was 97.36% and 41.24% higher than that with the bare AC air cathode and commercial Co3O4 respectively. The electrocatalytic behavior for their better performance was discussed in detail with the help of various structural and electrochemical techniques. The OHSNC was characterized via X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM). The results showed that the improved performance owed to the enhancement of both kinetics activity and the number of electron transfer in the ORR, and the internal resistance was largely reduced. Therefore, OHSNC was proved to be an excellent cathodic catalyst in AC air cathode MFC. PMID:26112347

  15. Neural network modeling of the kinetics of SO{sub 2} removal by fly ash-based sorbent

    SciTech Connect

    Raymond-Ooi, E.H.; Lee, K.T.; Mohamed, A.R.; Chu, K.H.

    2006-02-15

    The mechanistic modeling of the sulfation reaction between fly ash-based sorbent and SO 2 is a challenging task due to a variety reasons including the complexity of the reaction itself and the inability to measure some of the key parameters of the reaction. In this work, the possibility of modeling the sulfation reaction kinetics using a purely data-driven neural network was investigated. Experiments on SO{sub 2} removal by a sorbent prepared from coal fly ash/CaO/CaSO{sub 4} were conducted using a fixed bed reactor to generate a database to train and validate the neural network model. Extensive SO{sub 2} removal data points were obtained by varying three process variables, namely, SO{sub 2} inlet concentration (500-2000 mg/L), reaction temperature (60-80{sup o}C), and relative humidity (50-70%), as a function of reaction time (0-60 min). Modeling results show that the neural network can provide excellent fits to the SO{sub 2} removal data after considerable training and can be successfully used to predict the extent of SO{sub 2} removal as a function of time even when the process variables are outside the training domain. From a modeling standpoint, the suitably trained and validated neural network with excellent interpolation and extrapolation properties could have immediate practical benefits in the absence of a theoretical model.

  16. Acidification of rain by the oxidation of dissolved SO/sub 2/ and the absorption of HNO/sub 3/

    SciTech Connect

    Durham, J.L.; Barnes, H.M.; Overton, J.H. Jr.

    1984-01-01

    Most O3alculations have been performed for sub-cloud acidification of rain. The roles of chemical oxidation kinetics, mass transport rates for gas scavenging, and the raindrop size distribution have been examined. H/sub 2/O/sub 2/ (10 ppb) greatly dominates O/sub 3/ and Mn(+2) in oxidizing dissolved SO/sub 2/ to form H(-1) and SO/sub 4/(-2). HNO/sub 3/ is important for acidification of rain and it also slightly inhibits SO/sub 4/(-2) formation. Sub-cloud scavenging of H/sub 2/O/sub 2/ and HNO/sub 3/ is mass transport limited, thus causing the acidification of rain to be mass-transported limited. The Marshall-Palmer distribution results in greater predictions of acidity, SO/sub 4/(-2), and NO/sub 3/(-1) than the best distribution for raindrops larger than 0.2 mm. Sub-cloud acidification of rain is strongly dependent on: (a) the concentrations of SO/sub 2/, H/sub 2/O/sub 2/, and HNO/sub 3/, (b) the sub-cloud fall distance, and (c) the raindrop size distribution.

  17. SO/sub 2/ concentration estimates for New York City, 1880-1980. Final report

    SciTech Connect

    Husar, R.B.; Patterson, D.E.

    1985-04-01

    The purpose of this investigation was to estimate the yearly ambient concentration of SO/sub 2/ and SO/sub 4/ wet deposition from 1880 to 1980 for the greater New York City area. This information was used to reconstruct ambient concentrations at two New York Veterans Administration cemeteries, Cypress Hills and Long Island, for studying marble deterioration. This study which involved a determination of marble loss rate as a function of SO2 concentrations is the subject of another report. The methodology for developing the retrospective model to estimate yearly ambient concentrations since the turn of the century for the greater New York City area is presented in this report. The retrospective estimation of sulfur concentration and deposition required estimation of both local and regional emission trends since the turn of the century, along with suitable choice of a local and a regional dispersion model to relate emissions to ambient concentrations and deposition. The retrospective estimates are compared to observed SO2 concentrations. It needs no elaboration that the estimation of local and regional emissions pertinent to a given receptor, the quantification of the local and regional contributions to SO2 and to the wet deposition, and reconciliation with existing observations is a formidable task. Lacking data for the historical trends, many of the assumptions are based on best available science, and they should be revised with the availability of new knowledge.

  18. High SO{sub 2} removal duct injection: A low-cost FGD alternative

    SciTech Connect

    Nelson, S.G.

    1995-12-01

    Sorbent Technologies Corporation, of the United States, is currently developing and demonstrating a new waste free, retrofitable, high-SO{sub 2} removal duct-injection process. Up to 85 percent SO{sub 2} removal is achieved by simply injecting a new dry lime-based sorbent into the flue-gas duct, collecting the sorbent downstream in a particulate collector, and then recycling the sorbent. By avoiding large, expensive components, the process can have low capital costs, making it especially appropriate for smaller, older, less-utilized plants. The key to the new technology is the use of sorbent supports. Supported sorbents are produced by coating hydrated lime onto inexpensive mineral supports, such as exfoliated vermiculite or perlite. Consequently, there are no liquid, sludge, or solid wastes with the new technology. Once saturated with SO{sub 2}, the spent sorbent can be easily pelletized into a valuable soil-conditioning agricultural by-product, for the sustainable development that the future requires. This paper describes Sorbent Technologies` pilot demonstration of supported sorbent injection at the Ohio Edison Company`s R.E. Burger station. The Burger effort is also the first demonstration of the Electric Power Research Institute`s new {open_quotes}COHPAC{close_quotes} baghouse technology in a sorbent-injection desulfurization application.

  19. Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report No. 10, June 1--August 31, 1993

    SciTech Connect

    1993-12-31

    The NOXSO process is a dry, post-combustion flue gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from the flue gas of a coal-fired utility boiler. In the process, the SO{sub 2} is reduced to sulfur by-product (elemental sulfur, sulfuric acid, or liquid SO{sub 2}) and the NO{sub x} is reduced to nitrogen and oxygen. It is predicted that the process can economically remove 90% of the acid rain precursor gases from the flue gas stream in a retrofit or new facility. The objective of the NOXSO Demonstration Project is to design, construct, and operate a flue gas treatment system utilizing the NOXSO process at Ohio Edison`s Niles Plant Unit {number_sign}1. The effectiveness of the process will be demonstrated by achieving significant reductions in emissions of sulfur and nitrogen oxides. In addition, sufficient operating data will be obtained to confirm the process economics and provide a basis to guarantee performance on a commercial scale. The project is presently in the project definition and preliminary design phase. Data obtained during pilot plant testing which was completed on July 30, 1993 is being incorporated in the design of the commercial size plant. A suitable host site to demonstrate the NOXSO process on a commercial scale is presently being sought.

  20. Characterisation of Ba(OH){sub 2}–Na{sub 2}SO{sub 4}–blast furnace slag cement-like composites for the immobilisation of sulfate bearing nuclear wastes

    SciTech Connect

    Mobasher, Neda; Bernal, Susan A.; Hussain, Oday H.; Apperley, David C.; Kinoshita, Hajime; Provis, John L.

    2014-12-15

    Soluble sulfate ions in nuclear waste can have detrimental effects on cementitious wasteforms and disposal facilities based on Portland cement. As an alternative, Ba(OH){sub 2}–Na{sub 2}SO{sub 4}–blast furnace slag composites are studied for immobilisation of sulfate-bearing nuclear wastes. Calcium aluminosilicate hydrate (C–A–S–H) with some barium substitution is the main binder phase, with barium also present in the low solubility salts BaSO{sub 4} and BaCO{sub 3}, along with Ba-substituted calcium sulfoaluminate hydrates, and a hydrotalcite-type layered double hydroxide. This reaction product assemblage indicates that Ba(OH){sub 2} and Na{sub 2}SO{sub 4} act as alkaline activators and control the reaction of the slag in addition to forming insoluble BaSO{sub 4}, and this restricts sulfate availability for further reaction as long as sufficient Ba(OH){sub 2} is added. An increased content of Ba(OH){sub 2} promotes a higher degree of reaction, and the formation of a highly cross-linked C–A–S–H gel. These Ba(OH){sub 2}–Na{sub 2}SO{sub 4}–blast furnace slag composite binders could be effective in the immobilisation of sulfate-bearing nuclear wastes.

  1. Influence of air pollution on extrinsic childhood asthma

    SciTech Connect

    Berciano, F.A.; Dominguez, J.; Alvarez, F.V.

    1989-02-01

    A crossed comparative study was done with 248 extrinsic asthmatic children living either in polluted or non-polluted areas (mean emission per year of sedimentary material greater than or less than 300 mg/m2/day, respectively) to establish the influence of air pollution on childhood extrinsic asthma. The mean number of wheezing crises per year was significantly higher for the children living in polluted areas (10.4 versus 7.69). In addition, incidence of severe asthma (types II, III, and IV) in children living in polluted areas was markedly increased whereas the slight form of asthma (type I) was more frequent in children living in non-polluted areas. No correlation, however, between the wheezing episodes and levels of atmospheric contaminants (fumes and SO/sub 2/) was detected when a group of 84 extrinsic asthmatic children living in polluted areas was studied longitudinally for a year. The data indicate that air pollution, as an isolated agent, plays a transient role in the appearance of wheezing episodes in subjects with extrinsic asthma. Results also suggest that the air pollution may potentiate wheezing episodes via alternative mechanisms.

  2. Modelling of air pollution impacts from power stations in Kuwait

    SciTech Connect

    Al-Ajmi, D.N.; Abdal, Y. )

    1987-01-01

    Kuwait is undergoing rapid development with fast growth of both urban and industrial areas. The environmental impact of such activities is already noticeable. Conditions are therefore favorable for the use of air pollution models to supply adequate tools for effective air quality management in Kuwait. The Industrial Source Complex Long Term (ISCLT) dispersion model was developed by the U.S. Environmental Protection Agency in response to the need for comprehensive analytical techniques that can be used to evaluate the air quality impact of emissions from industrial sources. This model was used to predict the air quality impact of SO{sub 2} emissions from the Doha East and West Power Stations in Kuwait. The meteorological and emissions data and the seasonal and annual SO{sub 2} concentrations emitted from the power stations are described.

  3. SO>2-Resistant Immobilized Amine Sorbents for CO2 Capture

    SciTech Connect

    Tumuluri, Uma

    2014-01-01

    The solid amine sorbent for CO2 capture process has advantages of simplicity and low operating cost compared to the MEA (monoethanolamine) process. Solid amine sorbents reported so far suffered from either low CO2 capture capacity or low stability in the flue gas environment. This project is aimed at developing a SO>2-resistant solid amine sorbent for capturing CO2 from coal–fired power plants with SCR/FGD which emits SO>2ranging from 15 to 30 ppm and NO ranging from 5 to 10 ppm. The amine sorbent we developed in a previous project degraded rapidly with 65% decrease in the initial capture capacity in presence of 1% SO>2. This amine sorbent was further modified by coating with polyethyleneglycol (PEG) to increase the SO>2-resistance. Polyethylene glycol (PEG) was found to decrease the SO>2-amine interaction, resulting in the decrease in the maximum SO desorption temperature (Tmax ) of amine sorbent. The PEG-coated amine sorbent exhibited higher stability with only 40% decrease in the initial capture capacity compared to un-coated amine sorbents. The cost of the solid amine sorbent developed in this project is estimated to be less than $7.00/lb; the sorbent exhibited CO2 capture capacity more than 2.3 mmol/g. The results of this study provided the scientific basis for further development of SO>2-resistant sorbents.

  4. The role of SO{sub 4}{sup 2−} surface distribution in arsenic removal by iron oxy-hydroxides

    SciTech Connect

    Tresintsi, S.; Simeonidis, K.; Pliatsikas, N.; Vourlias, G.; Patsalas, P.; Mitrakas, M.

    2014-05-01

    This study investigates the contribution of chemisorbed SO{sub 4}{sup 2−} in improving arsenic removal properties of iron oxy-hydroxides through an ion-exchange mechanism. An analytical methodology was developed for the accurate quantification of sulfate ion (SO{sub 4}{sup 2−}) distribution onto the surface and structural compartments of iron oxy-hydroxides synthesized by FeSO{sub 4} precipitation. The procedure is based on the sequential determination of SO{sub 4}{sup 2−} presence in the diffuse and Stern layers, and the structure of these materials as defined by the sulfate-rich environments during the reaction and the variation in acidity (pH 3–12). Physically sorbed SO{sub 4}{sup 2−}, extracted in distilled water, and physically/chemically adsorbed ions on the oxy-hydroxide's surface leached by a 5 mM NaOH solution, were determined using ion chromatography. Total sulfate content was gravimetrically measured by precipitation as BaSO{sub 4}. To validate the suggested method, results were verified by X-ray photoelectron and Fourier-transformed infrared spectroscopy. Results showed that low precipitation pH-values favor the incorporation of sulfate ions into the structure and the inner double layer, while under alkaline conditions ions shift to the diffuse layer. - Graphical abstract: An analytical methodology for the accurate quantification of sulfate ions (SO{sub 4}{sup 2−}) distribution onto the diffuse layer, the Stern layer and the structure of iron oxy-hydroxides used as arsenic removal agents. - Highlights: • Quantification of sulfate ions presence in FeOOH surface compartments. • Preparation pH defines the distribution of sulfates. • XPS and FTIR verify the presence of SO{sub 4}{sup 2−} in the structure, the Stern layer the diffuse layer of FeOOH. • Chemically adsorbed sulfates control the arsenic removal efficiency of iron oxyhydroxides.

  5. Task 2.0 - Air Quality Assessment, Control, and Analytical Methods Subtask 2.11 - Lactic Acid FGD Additives From Sugar Beet Wastewater

    SciTech Connect

    Olson, Edwin S

    1998-02-01

    Organic buffers maintain the pH of the scrubber slurry in flue gas desulfurization (FGD) as the SO2 dissolves at the air-liquid interface. Inexpensive acids with an appropriate pKa are required for this application. The pKa of lactic acid (3.86) is between that of the interface and the recirculating slurry and will make soluble calcium ion available in large amounts. Currently lactic acid is somewhat expensive for this use, but this project will develop a new source of inexpensive lactate. Microbial action during the storage and processing of sugar beets forms lactic acid in concentrations as high 14 g/L in the processing water. The concentrations are lower than those occurring in conventional fermentation production of lactic acids, but since a considerable amount of water is involved in the processing of sugar beets in the Red River Valley (1 million gallons/day), a substantial amount of lactic acid or calcium lactate could be recovered as a by- product for use in FGD and other applications.

  6. Surface Structure Dependence of SO>2 Interaction with Ceria Nanocrystals with Well-defined Surface Facets

    SciTech Connect

    Tumuluri, Uma; Li, Meijun; Cook, Brandon G.; Sumpter, Bobby G.; Dai, Sheng; Wu, Zili

    2015-12-02

    The effects of the surface structure of ceria (CeO2) on the nature, strength, and amount of species resulting from SO>2 adsorption were studied using in situ IR and Raman spectroscopies coupled with mass spectrometry, along with first-principles calculations based on density functional theory (DFT). CeO2 nanocrystals with different morphologies, namely, rods (representing a defective structure), cubes (100 facet), and octahedra (111 facet), were used to represent different CeO2 surface structures. IR and Raman spectroscopic studies showed that the structure and binding strength of adsorbed species from SO>2 depend on the shape of the CeO2 nanocrystals. SO>2 adsorbs mainly as surface sulfites and sulfates at room temperature on CeO2 rods, cubes, and octahedra that were either oxidatively or reductively pretreated. The formation of sulfites is more evident on CeO2 octahedra, whereas surface sulfates are more prominent on CeO2 rods and cubes. This is explained by the increasing reducibility of the surface oxygen in the order octahedra < cubes < rods. Bulk sulfites are also formed during SO>2 adsorption on reduced CeO2 rods. The formation of surface sulfites and sulfates on CeO2 cubes is in good agreement with our DFT results of SO>2 interactions with the CeO2(100) surface. CeO2 rods desorb SO2 at higher temperatures than cubes and octahedra nanocrystals, but bulk sulfates are formed on CeO2 rods and cubes after high-temperature desorption whereas only some surface sulfates/sulfites are left on octahedra. This difference is rationalized by the fact that CeO2 rods have the highest surface basicity and largest amount of defects among the three nanocrystals, so they bind and react with SO>2 strongly and are the most degraded after SO>2 adsorption cycles. The

  7. Technical and economic evaluation of dry sorbent injection for SO/sub 2/ control using sodium compounds

    SciTech Connect

    Green, G.P.; Carr, R.C.; Hooper, R.G.

    1984-01-01

    Public Service Company of Colorado (PSCC) has committed to all-dry sorbent injection for SO/sub 2/ control on a new 500 MW coal-fired boiler, Pawnee Unit 2. Although no commitment has been made for construction of Pawnee 2, for engineering and planning purposes it is scheduled to begin service in 1990 burning western, low-sulfur, subbituminous coal. PSCC is currently the only electric utility to announce firm plans to employ this control technology. The purpose of this paper is to present the reasons for this commitment. It is hoped that this discussion will be of benefit to other electric utilities considering SO/sub 2/ control options.

  8. Impact of ethylene carbonate on ion transport characteristics of PVdF-AgCF{sub 3}SO{sub 3} polymer electrolyte system

    SciTech Connect

    Austin Suthanthiraraj, S.; Joice Sheeba, D.; Joseph Paul, B.

    2009-07-01

    The ionic transport in thin film plasticized polymer electrolytes based on polyvinylidene fluoride (PVdF) as the polymer host, silver triflate (AgCF{sub 3}SO{sub 3}) as salt and ethylene carbonate (EC) as plasticizer prepared by solution casting technique has been reported. Addition of silver triflate has resulted in an increase in the room temperature (298 K) electrical conductivity of the polymer from 10{sup -6} to 10{sup -5} S cm{sup -1} whereas incorporation of EC as the plasticizer has further enhanced the conductivity value by an order of magnitude to 10{sup -4} S cm{sup -1} owing to the possible decrease in crystallinity of the polymer matrix as revealed by the detailed temperature-dependent complex impedance, silver ionic transference number, Fourier transform infrared and X-ray diffraction measurements.

  9. A combined SO{sub 2} and NO{sub x} scrubbing process

    SciTech Connect

    Breault, R.W.; Bittenson, S.; Lani, B.

    1998-07-01

    A new wet scrubber process has been developed and undergone preliminary testing to verify the viability of a zero discharge system for SO{sub 2} and NO{sub x} removal. The process combines the Dravo ThioClear{reg{underscore}sign} process with Tecogen's TecoLytic{trademark} process. The integration of these two technologies results a system that removes both SO{sub 2} and NO{sub x} while producing only salable byproducts. These by-products are wall board grade gypsum, magnesium hydroxide and up to 60 weight percent fertilizer grade calcium nitrate solution. Hence, a zero waste, zero discharge wet scrubber system is being demonstrated. The core of the integrated technology consists of two parts. The first part is the ThioClear process. In this process, a highly alkaline magnesium sulfite solution is used to capture the SO{sub 2} in a high velocity (greater than 15 ft/s with a nominal design of 25 ft/s) horizontal scrubber. Once captured, the sulfites are oxidized to sulfates in an oxidizing vessel. The effluent from the oxidizer is reacted with a magnesium-enhanced lime slurry to raise the pH to about 10.5. At this higher pH, 6 to 10{micro} magnesium hydroxide precipitates and 80{micro} or larger gypsum precipitates are formed. Subsequent product purification produces salable gypsum and magnesium hydroxide. The flue gas continues through the high velocity horizontal scrubber passing through the TecoLytic{trademark} section. In this section, high voltage is applied to produce highly reactive excited species. These species interact with the water vapor present to produce hydroxyl radicals while simultaneously oxidizing the NO to NO{sub 2}. The hydroxyl radicals rapidly oxidize the NO{sub 2} to nitric acid which is scrubbed in the second stage of the horizontal scrubber with a calcium nitrate--lime solution. Bench scale tests have shown high potential. A pilot plant facility has been installed at Cincinnati Gas and Electric Company's Miami Fort facility. Pilot tests at

  10. Air pollution and plant life

    SciTech Connect

    Treshow, M.

    1984-01-01

    The publication of this volume could hardly have been more timely, for concern about the damage to plants from air pollution has grown rapidly in the last few years. The book comprises eighteen chapters by contributors of high repute. Three early chapters deal with Dispersion and Fate of Atmospheric Pollutants, Long Range Transport and Monitoring Levels and Effects of Air Pollutants. They provide essential reading for those working on effects in the field, and they set the scene for a contribution from the Volume Editor on the problems of diagnosis. The central chapters (7 to 11) provide, in considerable depth, a summary of the knowledge of the mechanism of action of pollutants on plants, in terms of physiology, biochemistry, and ultrastructure. Particularly valuable is the essay entitled Impact of Air Pollutant Combinations on Plants, which concludes that even though few generalizations are possible, there is now sufficient evidence to suggest that interactions between some pollutants (e.g. SO/sub 2/ and O/sub 3/, SO/sub 2/ and NO/sub 2/) may seriously damage some plants.

  11. Analysis of the Clean Air Act Amendments of 1990: A forecast of the electric utility industry response to Title IV, Acid Deposition Control

    SciTech Connect

    Molburg, J.C.; Fox, J.A.; Pandola, G.; Cilek, C.M.

    1991-10-01

    The Clean Air Act Amendments of 1990 incorporate, for the first time, provisions aimed specifically at the control of acid rain. These provisions restrict emissions of sulfur dioxide (SO{sub 2}) and oxides of nitrogen (NO{sub x}) from electric power generating stations. The restrictions on SO{sub 2} take the form of an overall cap on the aggregate emissions from major generating plants, allowing substantial flexibility in the industry`s response to those restrictions. This report discusses one response scenario through the year 2030 that was examined through a simulation of the utility industry based on assumptions consistent with characterizations used in the National Energy Strategy reference case. It also makes projections of emissions that would result from the use of existing and new capacity and of the associated additional costs of meeting demand subject to the emission limitations imposed by the Clean Air Act. Fuel-use effects, including coal-market shifts, consistent with the response scenario are also described. These results, while dependent on specific assumptions for this scenario, provide insight into the general character of the likely utility industry response to Title IV.

  12. Analysis of the Clean Air Act Amendments of 1990: A forecast of the electric utility industry response to Title IV, Acid Deposition Control

    SciTech Connect

    Molburg, J.C.; Fox, J.A.; Pandola, G.; Cilek, C.M.

    1991-10-01

    The Clean Air Act Amendments of 1990 incorporate, for the first time, provisions aimed specifically at the control of acid rain. These provisions restrict emissions of sulfur dioxide (SO[sub 2]) and oxides of nitrogen (NO[sub x]) from electric power generating stations. The restrictions on SO[sub 2] take the form of an overall cap on the aggregate emissions from major generating plants, allowing substantial flexibility in the industry's response to those restrictions. This report discusses one response scenario through the year 2030 that was examined through a simulation of the utility industry based on assumptions consistent with characterizations used in the National Energy Strategy reference case. It also makes projections of emissions that would result from the use of existing and new capacity and of the associated additional costs of meeting demand subject to the emission limitations imposed by the Clean Air Act. Fuel-use effects, including coal-market shifts, consistent with the response scenario are also described. These results, while dependent on specific assumptions for this scenario, provide insight into the general character of the likely utility industry response to Title IV.

  13. Improved emission calculations for PM{sub 10}, SO{sub 2} and H{sub 2}S from coke oven battery fugitive sources

    SciTech Connect

    Bhattacharyya, A.; McCollum, H.R.

    1995-12-01

    National Ambient Air Quality Standards (NAAQS) specify the allowable limit of particulate matter in ambient air. Particulate Matter, under 10 micron size (PM{sub 10}), is the inhalable part of total suspended particulate in air with direct adverse impact on human health and environment. To have a better understanding of fugitive emissions from coke oven doors, lids, offtakes, pushing, hot car travel and quenching, EPA has conducted studies and published factors for emissions from most of those sources. Unfortunately, many of those field tests were performed in the 70`s and 80`s, and the developed emission factors may no longer be valid for present day coke plant operation. To identify the sources of PM{sub 10}, H{sub 2}S and SO{sub 2} and to account for their loading in ambient air samplers, fugitive emission estimation from Clairton Works battery sources, such as decarbonization, soaking, guide machine leaks during pushing and hot car travel were included in the emissions inventory. With the idea of developing accurate emissions rates from those sources, Clairton personnel took a different approach. They went to the basics of coal carbonization. The authors of the paper gathered operating data regarding average flue temperature in batteries, tons of coal charged, coking time, decarbonization and soaking time in all the batteries of Clairton for a month and estimated the fugitive emissions from soaking, decarbonization, pushing, hot car travel and quenching. They used information from published literature to calculate these emissions. This paper includes all of the calculations and assumptions used in these estimates. The references are also included. This study is a demonstration of a pilot effort to consider a new approach for estimating fugitive emissions from coke battery sources. The authors acknowledge that further effort from agencies and industry is required to fine tune this approach.

  14. Method of using a nuclear magnetic resonance spectroscopy standard. [SO/sub 2/ in gases by fluorescence

    DOEpatents

    Spicer, L.D.; Bennett, D.W.; Davis, J.F.

    1983-05-09

    (CH/sub 3/)/sub 3/SiNSO is produced by the reaction of ((CH/sub 3/)/sub 3/SI)/sub 2/NH with SO/sub 2/. Also produced in the reaction are ((CH/sub 3/)/sub 3/Si)/sub 2/O and a new solid compound (NH/sub 4/)((CH/sub 3/)/sub 3/SiOSO/sub 2/). Both (CH/sub 3/)/sub 3/SiNSO and (NH/sub 4/)((CH/sub 3/)/sub 3/SiOSO/sub 2/) have fluorescent properties. The reaction of the subject invention is used in a method of measuring the concentration of SO/sub 2/ pollutants in gases. By the method, a sample of gas is bubbled through a solution of ((CH/sub 3/)/sub 3/Si)/sub 2/NH, whereby any SO/sub 2/ present in the gas will react to produce the two fluorescent products. The measured fluorescence of these products can then be used to calculate the concentration of SO/sub 2/ in the original gas sample. The solid product (NH/sub 4/)((CH/sub 3/)/sub 3/SiOSO/sub 2/) may be used as a standard in solid state NMR spectroscopy, wherein the resonance peaks of either /sup 1/H, /sup 13/C, /sup 15/N, or /sup 29/Si may be used as a reference.

  15. SO/sub 2/(g)-to-sulfate conversion rate in an oil-fired-power-plant plume in a fog bank

    SciTech Connect

    Eatough, D.J.; Arthur, R.J.; Eatough, N.L.; Hill, M.W.; Mangelson, N.F.; Richter, B.E.; Hansen, L.D.; Cooper, J.A.

    1983-01-01

    High acidity in rainfall, cloud droplets and fog droplets in areas influenced by anthropogenic sources of SO/sub 2/(g) and NO/sub x/(g) has been attributed to the formation of both H/sub 2/SO/sub 4/ and HNO/sub 3/. It has been suggested, based on the analysis of field data, that rapid conversion of SO/sub 2/(g) to sulfate must occur in cloud or fog droplets. Direct measurements of the rate of SO/sub 2/(g) to sulfate conversion in an oil-fired power plant plume as it passes through a fog bank are reported here. A conversion rate of 30+-4% SO/sub 2/(g) h/sup -1/ was found in the fog bank.

  16. Infrared absorption of C{sub 6}H{sub 5}SO{sub 2} detected with time-resolved Fourier-transform spectroscopy

    SciTech Connect

    Chu, L.-K.; Lee, Y.-P.

    2007-04-07

    C{sub 6}H{sub 5}SO{sub 2} radicals were produced upon irradiation of three flowing mixtures: C{sub 6}H{sub 5}SO{sub 2}Cl in N{sub 2}, C{sub 6}H{sub 5}Cl and SO{sub 2} in CO{sub 2}, and C{sub 6}H{sub 5}Br and SO{sub 2} in CO{sub 2}, with a KrF excimer laser at 248 nm. A step-scan Fourier-transform spectrometer coupled with a multipass absorption cell was employed to record the time-resolved infrared (IR) absorption spectra of reaction intermediates. Two transient bands with origins at 1087.7 and 1278.2 cm{sup -1} are assigned to the SO{sub 2}-symmetric and SO{sub 2}-antisymmetric stretching modes, respectively, of C{sub 6}H{sub 5}SO{sub 2}. Calculations with density-functional theory (B3LYP/aug-cc-pVTZ and B3P86/aug-cc-pVTZ) predict the geometry and vibrational wave numbers of C{sub 6}H{sub 5}SO{sub 2} and C{sub 6}H{sub 5}OSO. The vibrational wave numbers and IR intensities of C{sub 6}H{sub 5}SO{sub 2} agree satisfactorily with the observed new features. Rotational contours of IR spectra of C{sub 6}H{sub 5}SO{sub 2} simulated based on predicted molecular parameters agree satisfactorily with experimental results for both bands. The SO{sub 2}-symmetric stretching band is dominated by a- and c-type rotational structures and the SO{sub 2}-antisymmetric stretching band is dominated by a b-type rotational structure. When C{sub 6}H{sub 5}SO{sub 2}Cl was used as a precursor of C{sub 6}H{sub 5}SO{sub 2}, C{sub 6}H{sub 5}SO{sub 2}Cl was slowly reproduced at the expense of C{sub 6}H{sub 5}SO{sub 2}, indicating that the reaction Cl+C{sub 6}H{sub 5}SO{sub 2} takes place. When C{sub 6}H{sub 5}Br/SO{sub 2}/CO{sub 2} was used as a precursor of C{sub 6}H{sub 5}SO{sub 2}, features at 1186 and 1396 cm{sup -1} ascribable to C{sub 6}H{sub 5}SO{sub 2}Br were observed at a later period due to secondary reaction of C{sub 6}H{sub 5}SO{sub 2} with Br. Corresponding kinetics based on temporal profiles of observed IR absorption are discussed.

  17. EXPLORING IO'S ATMOSPHERIC COMPOSITION WITH APEX: FIRST MEASUREMENT OF {sup 34}SO{sub 2} AND TENTATIVE DETECTION OF KCl

    SciTech Connect

    Moullet, A.; Lellouch, E.; Moreno, R.; Gurwell, M.; Black, J. H; Butler, B.

    2013-10-10

    The composition of Io's tenuous atmosphere is poorly constrained. Only the major species SO{sub 2} and a handful of minor species have been positively identified, but a variety of other molecular species should be present, based on thermochemical equilibrium models of volcanic gas chemistry and the composition of Io's environment. This paper focuses on the spectral search for expected yet undetected molecular species (KCl, SiO, S{sub 2}O) and isotopes ({sup 34}SO{sub 2}). We analyze a disk-averaged spectrum of a potentially line-rich spectral window around 345 GHz, obtained in 2010 at the APEX 12 m antenna. Using different models assuming either extended atmospheric distributions or a purely volcanically sustained atmosphere, we tentatively measure the KCl relative abundance with respect to SO{sub 2} and derive a range of 4 × 10{sup –4}-8 × 10{sup –3}. We do not detect SiO or S{sub 2}O and present new upper limits on their abundances. We also present the first measurement of the {sup 34}S/{sup 32}S isotopic ratio in gas phase on Io, which appears to be twice as high as the Earth and interstellar medium reference values. Strong lines of SO{sub 2} and SO are also analyzed to check for longitudinal variations of column density and relative abundance. Our models show that, based on their predicted relative abundance with respect to SO{sub 2} in volcanic plumes, both the tentative KCl detection and SiO upper limit are compatible with a purely volcanic origin for these species.

  18. Food additives

    MedlinePlus

    Food additives are substances that become part of a food product when they are added during the processing or making of that food. "Direct" food additives are often added during processing to: Add nutrients ...

  19. Human health benefits of ambient sulfate aerosol reductions under Title IV of the 1990 Clean Air Act amendments

    SciTech Connect

    Chestnut, L.G.; Watkins, A.M.

    1997-12-31

    The Acid Rain Provisions (Title IV) of the Clean Air Act Amendments of 1990 call for about a 10 million ton reduction in annual SO{sub 2} emissions in the United States by the year 2010. Although the provisions apply nationwide, most of the reduction will take place in the eastern half of the United States, where use of high sulfur coal for electricity generation is most common. One potentially large benefit of Title IV is the expected reduction in adverse human health effects associated with exposure to ambient sulfate aerosols, a secondary pollutant formed in the atmosphere when SO{sub 2} is present. Sulfate aerosols are a significant constituent of fine particulate (PM{sub 2.5}). This paper combines available epidemiologic evidence of health effects associated with sulfate aerosols and economic estimates of willingness to pay for reductions in risks or incidence of health effects with available estimates of the difference between expected ambient sulfate concentrations in the eastern United States and southeastern Canada with and without Title IV to estimate the expected health benefits of Title IV. The results suggest a mean annual benefit in the eastern United States of $10.6 billion (in 1994 dollars) in 1997 and $40.0 billion in 2010, with an additional $1 billion benefit each year in Ontario and Quebec provinces.

  20. Food additives

    PubMed Central

    Spencer, Michael

    1974-01-01

    Food additives are discussed from the food technology point of view. The reasons for their use are summarized: (1) to protect food from chemical and microbiological attack; (2) to even out seasonal supplies; (3) to improve their eating quality; (4) to improve their nutritional value. The various types of food additives are considered, e.g. colours, flavours, emulsifiers, bread and flour additives, preservatives, and nutritional additives. The paper concludes with consideration of those circumstances in which the use of additives is (a) justified and (b) unjustified. PMID:4467857

  1. Vinyl capped addition polyimides

    NASA Technical Reports Server (NTRS)

    Vannucci, Raymond D. (Inventor); Malarik, Diane C. (Inventor); Delvigs, Peter (Inventor)

    1991-01-01

    Polyimide resins (PMR) are generally useful where high strength and temperature capabilities are required (at temperatures up to about 700 F). Polyimide resins are particularly useful in applications such as jet engine compressor components, for example, blades, vanes, air seals, air splitters, and engine casing parts. Aromatic vinyl capped addition polyimides are obtained by reacting a diamine, an ester of tetracarboxylic acid, and an aromatic vinyl compound. Low void materials with improved oxidative stability when exposed to 700 F air may be fabricated as fiber reinforced high molecular weight capped polyimide composites. The aromatic vinyl capped polyimides are provided with a more aromatic nature and are more thermally stable than highly aliphatic, norbornenyl-type end-capped polyimides employed in PMR resins. The substitution of aromatic vinyl end-caps for norbornenyl end-caps in addition polyimides results in polymers with improved oxidative stability.

  2. Stomatal response and leaf injury of Pisum sativum L. with SO/sub 2/ and O/sub 3/ exposures. I. Influence of pollutant level and leaf maturity

    SciTech Connect

    Olszyk, D.M.; Tibbitts, T.W.

    1981-03-01

    Plants of Pisum sativum L. Alsweet were grown under a controlled environment and exposed to SO/sub 2/ and O/sub 3/ to determine whether changes in stomatal aperture during exposure were related to subsequent leaf injury. Stomata consistently closed with injurious levels of SO/sub 2/ and O/sub 3/. Measurements with diffusion porometers demonstrated approx. = 75 and 25% lower conductance with SO/sub 2/ and O/sub 3/ exposures, respectively, compared to the conductance of control plants. Stomata also showed a closing response with noninjurious levels of SO/sub 2/ but an opening response with noninjurious levels of O/sub 3/. Stomata closed to the same degree with combinations of SO/sub 2/ plus O/sub 3/ as with SO/sub 2/ alone. Stomata of expanding leaves closed more during pollutant exposures than stomata of expanded leaves. The abaxial and adaxial stomata both exhibited closure with SO/sub 2/ and combinations of SO/sub 2/ plus O/sub 3/, but abaxial stomata tended to close and adaxial stomata tended to open with exposure to O/sub 3/ alone. The changes in stomatal aperture were not closely correlated with the amount of leaf injury produced by different pollutant levels. Stomata closed, not only with exposure to pollutant levels that caused severe necrosis, but also with levels that caused only a trace of injury. There was no evidence of a reduced amount of closure or even stomatal opening with combinations of SO/sub 2/ and O/sub 3/ compared to plants exposed to the pollutants alone to explain the large amount of injury to plants exposed to pollutant combinations.

  3. Direct effects of energy-related air pollutants on plant sexual reproduction. Progress report, February 1, 1981-January 31, 1982

    SciTech Connect

    Ragsdale, H.L.; Murdy, W.H.

    1982-10-07

    Direct effects of SO/sub 2/ and NO/sub 2/ on plant sexual reproduction were studied including essential botanical research into modes of anthesis, pollination, pollen germination and pollen tube growth. Much of the present scientific knowledge of the direct in vivo effects of the major air pollutants, SO/sub 2/ and NO/sub 2/, on plant sexual reproduction is a direct result of studies accomplished under this DOE contract. It is our intention to carry this research forward to include similar assessment of a third major air pollutant, ozone.

  4. Sorbent preparation/modification/additives. Final report, September 1, 1992--November 30, 1993

    SciTech Connect

    Prudich, M.E.; Venkataramakrishnan, R.

    1994-02-01

    Sorbent preparation techniques used today have generally been adapted from techniques traditionally used by the lime industry. Traditional dry hydration and slaking processes have been optimized to produce materials intended for use in the building industry. These preparation techniques should be examined with an eye to optimization of properties important to the SO{sub 2} capture process. The study of calcium-based sorbents for sulfur dioxide capture is complicated by two factors: (1) little is known about the chemical mechanisms by which the standard sorbent preparation and enhancement techniques work, and (2) a sorbent preparation technique that produces a calcium-based sorbent that enjoys enhanced calcium utilization in one regime of operation [flame zone (>2400 F), in-furnace (1600--2400 F), economizer (800--1100 F), after air preheater (<350 F)] may not produce a sorbent that enjoys enhanced calcium utilization in the other reaction zones. Again, an in-depth understanding of the mechanism of sorbent enhancement is necessary if a systematic approach to sorbent development is to be used. As a long-term goal, an experimental program is being carried out for the purpose of (1) defining the effects of slaking conditions on the properties of calcium-based sorbents, (2) determining how the parent limestone properties of calcium-based sorbents, and (3) elucidating the mechanism(s) relating to the activity of various dry sorbent additives. An appendix contains a one-dimensional duct injection model with modifications to handle the sodium additives.

  5. Anthropogenic SO{sub 2}/NO{sub x} committee--current status

    SciTech Connect

    Benkovitz, C.M.

    1993-04-01

    Current activities of the Anthropogenic SO{sub 2}/NO{sub x} Committee center around the compilation of Version 1 of the GEIA inventories. These inventories will be based on the GEIA-specified 1{degrees} by 1{degrees} grid (lower left corner at 180{degrees}W/90{degrees}S, west to east and south to north), reflect 1985 emissions and consist of two data sets: Version 1A inventories with annual emissions at one level and Version 1B inventories with seasonal emissions, two vertical levels (defined at 100 m) and sectoral split information. The basic information used for both versions of the GEIA inventories will be identical; i.e., emissions totals across both inventories will be the same. Work is being carried out in two complementary working groups; Carmen Benkovitz, Brookhaven National Laboratory, Upton, NY, USA heads the work on the annual inventory, Eva Voldner, Atmospheric Environment Services, Canada and Trevor Scholtz, ORTECH International, Canada, head the work on the seasonal inventory.

  6. High temperature membranes for H[sub 2]S and SO[sub 2] separations

    SciTech Connect

    Winnick, J.

    1992-01-01

    Successful removal of SO[sub x] from flue gas depends on the development of a membrane able to achieve a current density of 50 mA/cm[sup 2] at a total voltage of approximately 1V. Flooding of electrode hasbeen identified as a problem, leading to increasing polarization over time. The resulting reduction of surface area also tends to limit the mass transfer flux, reducing the efficiency of the cell. To reduce flooding, new materials and techniques of manufacture will be investigated, in the attempt to produce a ceramic membrane of approximately 50% theoretical density. This membrane must have proper pore size distribution to ensure sufficient capillary force to prevent impregnated electrolyte from flooding electrodes, and subsequently drying the ceramic membrane. Various methods of matrix production were studied this quarter: tape casting, pressing and sintering, and slip casting. Each will be discussed in turn. Electrolyte introduction to the cell is a continuing problem. The development of a method is still being investigated. Ideally, the electrolyte would be introduced as powder with binder in a green body. This binder would burn away at temperatures of approximately 300[degrees]C, leaving pure electrolyte to melt and complete the ionic path necessary for the electrochemical cell. The electrolyte used this quarter was, exclusively, a 90 wt % K[sub 2]S[sub 2]O[sub 7]/10 wt % V[sub 2]O[sub 5] mixture.

  7. TVA`s Cumberland Units 1&2 SO{sub 2} removal system - an update

    SciTech Connect

    Buckner, J.H.; Brodsky, I.S.; Muraskin, D.J.

    1995-06-01

    Tennessee Valley Authority`s Cumberland Fossil Plant (CUF) is a Phase I facility listed under the 1990 CAA Amendments. Units 1 & 2 are two 1300 MWe coal fired units which presently bum an eastern bituminous coal containing approximately 2.8% sulfur. The Flue Gas Desulfurization (FGD) system reduces sulfur dioxide (SO{sub 2}) emissions from Units 1 and 2 by means of wet limestone - forced oxidation scrubbing. The absorber modules were provided by ABB Environmental Systems (ABBES) with balance of plant engineering, construction management, and startup provided by Raytheon Engineers and Constructors (RE&C) under a partnership arrangement with TVA. The FGD systems for Unit 1 & 2 were brought on-line October 12, 1994 and December 14, 1994, respectively. This paper will present a brief description of the overall project, the design basis, challenging problems and solutions during construction and initial startup. Specific topics will include: (1) Optimization studies underway; (2) Unique design aspects of the facility; (3) A description of the absorber and supporting systems including the limestone barge unloader, ball mill system for reagent preparation, and draft system upgrades; and (4) Experience gained in management of a large project under the unique partnership agreement.

  8. Climate regulation by marine phytoplankton. : A test by anthropogenic SO/sub 2/ emissions

    SciTech Connect

    Schwartz, S.E.

    1989-05-01

    The potential sensitivity of global mean albedo and temperature to N prompted a novel suggestion consistent with the Gaia hypothesis for regulation of global climate by marine phytoplankton. Certain species of coccolithophores excrete dimethylsulfide (DMS), and this DMS is arguably the principal source of reduced sulfur gases in the global atmosphere and, in the absence of anthropogenic SO/sub 2/, the principal source of atmospheric gaseous sulfur species. Such gaseous sulfur species are oxidized in the atmosphere to form sulfuric acid, which rapidly forms an aerosol. Since sulfate-containing AP are highly efficient CCN, it is argued that an increase in DMS production by marine phytoplankton would yield increased concentrations of CCN, resulting in increased cloud albedo, decreased surface insolation, and decreased planetary temperature. It is further hypothesized that such decreased insolation or temperature might result in decreased production of DMS by marine phytoplankton, i.e., that the process might constitute a negative feedback loop for regulation of planetary climate by marine microorganisms. 18 refs., 3 figs., 1 tab.

  9. Regional air quality in the four corners studys region: modeling approach

    SciTech Connect

    Nochumson, D.

    1982-01-01

    A two-dimensional Eulerian air pollutant transport model was used in an air quality study of the Four Corners region conducted for the National Commission on Air Quality. The regional modeling methodology and some sample results from the regional air quality analysis are presented. One major advantage of the regional transport model that was employed is that its solution involves the calculation of transfer coefficients that relate emissions to ambient concentrations and deposition and which can be used repeatedly to evaluate alternative scenarios and regulatory policies which represent different emission source configurations. The regional transport model was used in the calculation of the concentration and deposition of SO/sub 2/, SO/sub 4/, and primary fine particulates; and these estimates were used as inputs to regional atmospheric visibility and mass budget calculations. Previous studies have shown that the methods used in the regional air quality analysis give good agreement when comparing observed and estimated values.

  10. Conductivity and optical band gaps of polyethylene oxide doped with Li{sub 2}SO{sub 4} salt

    SciTech Connect

    Chapi, Sharanappa Raghu, S. Subramanya, K. Archana, K. Mini, V. Devendrappa, H.

    2014-04-24

    The conductivity and optical properties of Li{sub 2}SO{sub 4} doped polyethylene oxide (PEO) films were studied. The polymer electrolyte films are prepared using solution casting technique. The material phase change was confirmed by X-ray diffraction (XRD) technique. Optical absorption study was conducted using UV- Vis. Spectroscopy in the wavelength range 190–1100nm on pure and doped PEO films. The direct and indirect optical band gaps were found decreased from 5.81–4.51eV and 4.84–3.43eV respectively with increasing the Li{sub 2}SO{sub 4}. The conductivity found to increases with increasing the dopant concentration due to strong hopping mechanism at room temperature.

  11. Technical status report development of lime based in-duct scrubbing - A cost effective SO/sub 2/ control technology

    SciTech Connect

    Shilling, N.Z.; Samuel, E.A.; Pennline, H.

    1986-04-01

    Lime Based In-Duct Scrubbing (LIBIDS) was one of the candidate technologies receiving contract awards for pilot demonstration by the U.S. Department of Energy under the Acid Rain Precurser program. The concept as developed by General Electric utilizes rotary atomization of lime slurry directly within flue gas carrying ductwork to remove SO/sub 2/. This promises to be a very low capital cost method of SO/sub 2/ control with capital plus levelized operating cost estimated to be $364/KW. Several significant technical milestones have been passed relative to proof of principle and ultimate commercialization. Based on positive results from a laboratory and supporting analytical work, a detailed engineering design has begun for a pilot plant.

  12. Measurement of the deposition and fate of {sup 35}SO{sub 2} in a pine plantation

    SciTech Connect

    Gay, D.W.; Murphy, C.E. Jr.

    1988-12-31

    An experiment was carried out to determine the uptake rate and fate of SO{sub 2} absorbed by the forest canopy. The radioactive tracer, {sup 35}S was used. Branches of loblolly pine were exposed to {sup 35}SO{sub 2} in the field with a portable chamber. The exposed branches were excised and a sample of needles was immediately washed with distilled water. The needles and water collected in the field was analyzed for {sup 35}S content. The results indicated that a portion of the {sup 35}S could be washed from the needles and another portion was not removed with a water rinse. The portion that could not be removed by rinsing was absorbed at a rate, and followed patterns of absorption, that suggested that absorption was controlled by stomatal diffusion, and thus was internal. The {sup 35}S that could be removed by rinsing appeared to be surface absorption.

  13. Influence of calcium content of biomass-based materials on simultaneous NOx and SO{sub 2} reduction

    SciTech Connect

    Sarma V. Pisupati; Sumeet Bhalla

    2008-04-01

    Pyrolysis products of biomass (bio-oils) have been shown to cause a reduction in NOx emissions when used as reburn fuels in combustion systems. When these bio-oils are processed with lime, calcium is ion-exchanged and the product is called BioLime. BioLime, when introduced into a combustion chamber, pyrolyzes and produces volatile products that reduce NOx emissions through reburn mechanisms. Simultaneously, calcium reacts with SO{sub 2} to form calcium sulfate and thus reduces SO{sub 2} emissions. This paper reports the characterization of composition and pyrolysis behavior of two BioLime products and the influence of feedstock on pyrolysis products. Thermogravimetric analysis (TGA) and {sup 13}C-CP/MAS NMR techniques were used to study the composition of two biomass-based materials. The composition of the pyrolysis products of BioLime was determined in a laboratory scale flow reactor. The effect of BioLime composition on NOx and SO{sub 2} reduction performance was evaluated in a 146.5 kW pilot-scale, down fired combustor (DFC). The effect of pyrolysis gas composition on NOx reduction is discussed. The TGA weight loss curves of BioLime samples in an inert atmosphere showed two distinct peaks corresponding to the decomposition of light and heavy components of the BioLime and a third distinct peak corresponding to secondary thermal decomposition of char. The study also showed that BioLime sample with lower content of residual lignin derivatives and lower calcium content produced more volatile compounds upon pyrolysis in the combustor and achieved higher NOx reduction (15%). Higher yields of pyrolysis gases increased the NO reduction potential of BioLime through homogeneous gas phase reactions. Calcium in BioLime samples effectively reduced SO{sub 2} emissions (60-85%). 36 refs., 6 figs., 3 tabs.

  14. Low temperature SO{sub 2} removal with solid sorbents in a circulating fluidized bed absorber. Final report

    SciTech Connect

    Lee, S.K.; Keener, T.C.

    1994-10-10

    A novel flue gas desulfurization technology has been developed at the University of Cincinnati incorporating a circulating fluidized bed absorber (CFBA) reactor with dry sorbent. The main features of CFBA are high sorbent/gas mixing ratios, excellent heat and mass transfer characteristics, and the ability to recycle partially utilized sorbent. Subsequently, higher SO{sub 2} removal efficiencies with higher overall sorbent utilization can be realized compared with other dry sorbent injection scrubber systems.

  15. Food additives.

    PubMed

    Berglund, F

    1978-01-01

    The use of additives to food fulfils many purposes, as shown by the index issued by the Codex Committee on Food Additives: Acids, bases and salts; Preservatives, Antioxidants and antioxidant synergists; Anticaking agents; Colours; Emulfifiers; Thickening agents; Flour-treatment agents; Extraction solvents; Carrier solvents; Flavours (synthetic); Flavour enhancers; Non-nutritive sweeteners; Processing aids; Enzyme preparations. Many additives occur naturally in foods, but this does not exclude toxicity at higher levels. Some food additives are nutrients, or even essential nutritents, e.g. NaCl. Examples are known of food additives causing toxicity in man even when used according to regulations, e.g. cobalt in beer. In other instances, poisoning has been due to carry-over, e.g. by nitrate in cheese whey - when used for artificial feed for infants. Poisonings also occur as the result of the permitted substance being added at too high levels, by accident or carelessness, e.g. nitrite in fish. Finally, there are examples of hypersensitivity to food additives, e.g. to tartrazine and other food colours. The toxicological evaluation, based on animal feeding studies, may be complicated by impurities, e.g. orthotoluene-sulfonamide in saccharin; by transformation or disappearance of the additive in food processing in storage, e.g. bisulfite in raisins; by reaction products with food constituents, e.g. formation of ethylurethane from diethyl pyrocarbonate; by metabolic transformation products, e.g. formation in the gut of cyclohexylamine from cyclamate. Metabolic end products may differ in experimental animals and in man: guanylic acid and inosinic acid are metabolized to allantoin in the rat but to uric acid in man. The magnitude of the safety margin in man of the Acceptable Daily Intake (ADI) is not identical to the "safety factor" used when calculating the ADI. The symptoms of Chinese Restaurant Syndrome, although not hazardous, furthermore illustrate that the whole ADI

  16. Synergistic effect of flyash and SO{sub 2} on development of cucumber (Cucumis sativus L.) leaf injury

    SciTech Connect

    Tung, G.; McIlveen, W.D.; Jones, R.D.

    1995-10-01

    In a two-factorial experiment, sulfur dioxide alone at concentration of 131 {micro}g/m{sup 3} over long exposures or flyash for either coal or oil combustion alone applied onto cucumber (Cucumis sativus L.) foliage causes no visible injury. However, if both flyash and sulfur dioxide were presented simultaneously, a specific mosaic-chlorosis symptom developed on leaves. A synergistic effect was thus demonstrated. Histopathology of the mosaic-chlorosis symptom was studied. An unusual pattern of tissue abnormally initiated from the collapse of the anticlinal cell walls of the upper epidermal cells and progressed along cell walls into mesophyll tissues. Cellular injury at the lower spongy tissues typical of that caused by SO{sub 2} was also observed. A significant elevation of sulfate-sulfur in the leaves treated with a combination of SO{sub 2} and flyash was demonstrated. Significant interactions between the two factors were found for both injury and sulfur chemistry. This suggests that flyash deposits on the leaf surface play a catalytic role in oxidizing atmospheric sulfur dioxide continuously to form sulfuric acid (H{sub 2}SO{sub 4}) in situ. This acid could infiltrate into mesophyll damage cells and tissues en route.

  17. High-temperature phase transformation and topochemical nature in ferroelastic (NH{sub 4}){sub 2}SO{sub 4}

    SciTech Connect

    Lee, Kwang-Sei; Oh, In-Hwan; Ko, Jae-Hyeon

    2014-04-01

    The electrical conductivity of ferroelastic ammonium sulfate (NH{sub 4}){sub 2}SO{sub 4} revealed an anomaly at around 130 °C (=403 K, T{sub P}) on heating with large and irreversible thermal hysteresis through thermal cycle. Ferroelastic domain walls and surface morphology of (NH{sub 4}){sub 2}SO{sub 4} were investigated by hot-stage polarizing microscopy. Structural phase transition from an orthorhombic ferroelastic phase to a hexagonal paraelastic phase was not identified at T{sub P} upon heating. On further heating above T{sub P}, microscopic spots appeared and grew on the crystal surface, suggesting that the high-temperature anomaly at T{sub P} was an indication of an onset of thermal decomposition controlled by topochemical factors. The increase of electrical conductivity above T{sub P} was attributed to proton migration. - Graphical abstract: Surface morphology of the (100) face of (NH{sub 4}){sub 2}SO{sub 4} on heating, showing chemical reaction at the surface. - Highlights: • We investigate the high-temperature phase transformation of ammonium sulfate. • The increasing conductivity upon heating is attributed to proton migration. • Structural phase transition from orthorhombic to hexagonal phase is not confirmed. • High-temperature anomaly is related to an onset of thermal decomposition. • The nature of the high-temperature anomaly is topochemical controlled by defects.

  18. Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report No. 11, September 1--November 30, 1993

    SciTech Connect

    1993-12-31

    The NOXSO process is a dry, post-combustion flue gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from the flue gas of a coal-fired utility boiler. In the process, the SO{sub 2} is reduced to sulfur by-product and the NO{sub x} is reduced to nitrogen and oxygen. It is predicted that the process can economically remove 90% of the acid rain precursor gases from the flue gas stream in a retrofit or new facility. The objective of the NOXSO Demonstration Project is to design, construct, and operate a flue gas treatment system utilizing the NOXSO process. The effectiveness of the process will be demonstrated by achieving significant reductions in emissions of sulfur and nitrogen oxides. In addition, sufficient operating data will be obtained to confirm the process economics and provide a basis to guarantee performance on a commercial scale. The project is presently in the project definition and preliminary design phase. Data obtained during pilot plant testing which was completed on July 30, 1993 is being incorporated in the design of the commercial size plant. A suitable host site to demonstrate the NOXSO process on a commercial scale is presently being sought. Preliminary engineering studies provided information to decide on the basic plant arrangement. A scaled up POC design was selected as the general arrangement of choice based on a cost versus technical risk assessment. The first step in developing an adsorber computer simulation was completed. Several processes for producing liquid SO{sub 2} from the regenerator offgas were developed and evaluated. It was concluded that the Claus and burn process which involves making elemental sulfur as an intermediate product was the best choice. The NOXSO process computer simulation was updated to include semi-plug solids flow through the fluidized beds of the sorbent heater and cooler. Heat loss calculations were also added.

  19. Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report No. 12, December 1, 1993--February 28, 1994

    SciTech Connect

    1994-12-31

    The NOXSO process is a dry, post-combustion flue gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from the flue gas of a coal-fired utility boiler. In the process, the SO{sub 2} is reduced to sulfur by-product and the NO{sub x} is reduced to nitrogen and oxygen. It is predicted that the process can economically remove 90% of the acid rain precursor gases from the flue gas stream in a retrofit or new facility. The objective of the NOXSO Demonstration Project is to design, construct, and operate a flue gas treatment system utilizing the NOXSO process. The effectiveness of the process will be demonstrated by achieving significant reductions in emissions of sulfur and nitrogen oxides. In addition, sufficient operating data will be obtained to confirm the process economics and provide a basis to guarantee performance on a commercial scale. The project is presently in the project definition and preliminary design phase. Data obtained during pilot plant testing which was completed on July 30, 1993 is being incorporated in the design of the commercial size plant. A suitable host site to demonstrate the NOXSO process on a commercial scale is presently being sought. The plant general arrangement has been revised to incorporate principles used in the design of fluidized catalytic cracking (FCC) plants. A NOXSO plant availability analysis was prepared using operating experience from the recently completed pilot plant as a basis. The impact of water desorption in the sorbent heater and water adsorption in the sorbent cooler has been quantified and incorporated into the NOXSO process simulator. NOXSO process economics has been updated based on the present design. Capital cost for a 500 MW plant designed to remove 98% of the SO{sub 2} and 85% of the NO{sub x} is estimated at $247/kW.

  20. Tear pH, air pollution, and contact lenses

    SciTech Connect

    Andres, S.; Garcia, M.L.; Espina, M.; Valero, J.; Valls, O.

    1988-08-01

    We analyzed the tear pH of a random sample of 100 subjects, divided into 3 groups according to the stability of their precorneal tear film (normal eyes, borderline; and dry eyes). The average pH value obtained was 7.52. The pH for borderline and dry eyes was higher than for normal eyes. The purpose of this study was to determine the influence of air pollution, specifically sulfur dioxide (SO/sub 2/), on the tear pH. We found that air pollution affected the lacrimal pH, which decreased when the atmospheric SO/sub 2/ increased. Finally, we studied the effect of soft contact lens wear on tear pH after 7 days of contact lens adaptation by assessing the tear pH decrease. We took into account the influence of the sex and age of subjects on the results obtained.

  1. Performance Boosting Additive

    NASA Technical Reports Server (NTRS)

    1999-01-01

    Mainstream Engineering Corporation was awarded Phase I and Phase II contracts from Goddard Space Flight Center's Small Business Innovation Research (SBIR) program in early 1990. With support from the SBIR program, Mainstream Engineering Corporation has developed a unique low cost additive, QwikBoost (TM), that increases the performance of air conditioners, heat pumps, refrigerators, and freezers. Because of the energy and environmental benefits of QwikBoost, Mainstream received the Tibbetts Award at a White House Ceremony on October 16, 1997. QwikBoost was introduced at the 1998 International Air Conditioning, Heating, and Refrigeration Exposition. QwikBoost is packaged in a handy 3-ounce can (pressurized with R-134a) and will be available for automotive air conditioning systems in summer 1998.

  2. Adipic gets the acid test as flue gas scrubber additive

    SciTech Connect

    Miller, I.R.

    1980-02-11

    The first full-scale demonstration of adipic acid for such use, to be conducted early in the summer of 1980 in a 200 MW power plant burning high-sulfur coal, is designed to clarify the costs and show how to reduce losses of adipic acid via degradation. Adipic acid improves SO/sub 2/ removal by acting as a buffer to limit the pH drop normally occurring at the gas-liquid interface so that the higher SO/sub 2/ concentration in the surface film improves liquid-phase mass transfer; it also promotes higher limestone utilization. Prepared by the Tennessee Valley Authority, a preliminary economic analysis for a 500 MW plant burning 4% sulfur coal indicates that the addition of 1500 ppM of adipic acid (limestone at $7/ton and the acid at $840/ton) would raise SO/sub 2/ removal from 90 to 95%, reduce the total capital investment from $41.5 to $39.5 million, and have a first year revenue requirement of $19.9 million vs. $20.9 million without the acid. The large-scale trial will also help clarify concern over unpleasant odors that have been reported at test sites of the limestone/adipic system; valeric acid has been identified as the cause.

  3. Estimating the hydrogen ion concentration in concentrated NaCl and Na{sub 2}SO{sub 4} electrolytes

    SciTech Connect

    Rai, D.; Felmy, A.R.; Juracich, S.P.; Rao, F.

    1995-06-01

    Combination glass electrodes were tested for determining H{sup +} concentrations in concentrated pure and mixed NaCl and Na{sub 2}SO{sub 4} solutions, as well as natural brine systems. NaCl, Na{sub 2}SO{sub 4}, and mixtures of NaCl and Na{sub 2}SO{sub 4} solutions were analyzed. Correction factors for estimating pC{sub H}{sup +} (negative logarithm of H{sup +} concentration) were determined from measured/observed pH values. Required Gran-type titrations were done with HCl and/or NaOH. The titration method is described and a step-by-step procedure provided; it has been used previously for determining pC{sub H}{sup +} values of synthetic chloride-dominated brines. Precautions are required to determine correction factors for electrolytes that react with H{sup +} or OH{sup {minus}} [sulfate brines for titration with acid; magnesium brines for titration with base because of precipitation of Mg(OH)2]. Correction factors A (pC{sub H}{sup +} = pH{sub ob} + A) from HCl titrations were similar to those from NaOH titrations where the concentration of free H{sup +} was calculated using a thermodynamic model. These values should be applicable to solns with a very large range in measured pH values (2 to 12). Because a large number of solns were titrated with HCl and the A values are similar for HCl and NaOH titrations, the A values for NaCl and Na2SO4 solns were fit as a function of molality to allow extrapolation. For NaCl solns 0 to 6.0 M, A can be obtained by multiplying the molality by 0.159. For Na2SO4 solns 0 to 2.0 M, the values of A can be obtained from (0.221 {minus} 0.549X + 0.201X{sup 2}), where X is the molality of Na{sub 2}SO{sub 4}. Orion-Ross electrode evaluations indicated that the A values did not differ significantly for different electrodes. Results suggest that the data in this report can be used to estimate A values for different NaCl and Na{sub 2}SO{sub 4} solns even for noncalibrated electrodes.

  4. Health effects of air pollution due to coal combustion in the Chestnut Ridge region of Pennsylvania

    SciTech Connect

    Batterman, S.; Golomb, D.

    1985-08-01

    This study used the seventeen monitor air quality network in the Chestnut Ridge region of Pennsylvania to evaluate the effect of pollutant trends and representations on measures of exposure. Data consisted of four and five years of SO/sub 2/ and TSP measurements, respectively, and were considered in deriving exposure models. A cross-sectional study of 4071 children aged 6 to 11 years of age was conducted in the spring of 1979. Standardized children's questionnaires were distributed to the parents and returned by the children to school, where spirometry was performed. The region was divided into low, moderate and high pollution areas on the basis of the 1974-1978, 3 h, 24 h, and annual averages for SO/sub 2/. After adjusting the respiratory symptom response outcomes and the pulmonary function levels for known predictors, no significant association was noted for level of SO/sub 2/. 65 refs., 16 figs., 19 tabs.

  5. Implications of the Clean Air Act acid rain title on industrial boilers

    SciTech Connect

    Maibodi, M. )

    1991-11-01

    This paper discusses the impacts of the 1990 Clean Air Act Amendments related to acid rain controls, as they apply to industrial boilers. Emphasis is placed on explaining the Title IV provisions of the Amendments that permit nonutility sources to participate in the SO{sub 2} allowance system. The allowance system, as it pertains to industrial boiler operators, is described, and the opportunities for operators to trade and/or sell SO{sub 2} emission credits is discussed. The paper also reviews flue gas desulfurization system technologies available for industrial boiler operators who may choose to participate in the system. Furnace sorbent injection, advanced silicate process, lime spray drying, dry sorbent injection, and limestone scrubbing are described, including statements of their SO{sub 2} removing capability, commercial status, and costs. Capital costs, levelized costs and cost-effectiveness are presented for these technologies.

  6. Potlining Additives

    SciTech Connect

    Rudolf Keller

    2004-08-10

    In this project, a concept to improve the performance of aluminum production cells by introducing potlining additives was examined and tested. Boron oxide was added to cathode blocks, and titanium was dissolved in the metal pool; this resulted in the formation of titanium diboride and caused the molten aluminum to wet the carbonaceous cathode surface. Such wetting reportedly leads to operational improvements and extended cell life. In addition, boron oxide suppresses cyanide formation. This final report presents and discusses the results of this project. Substantial economic benefits for the practical implementation of the technology are projected, especially for modern cells with graphitized blocks. For example, with an energy savings of about 5% and an increase in pot life from 1500 to 2500 days, a cost savings of $ 0.023 per pound of aluminum produced is projected for a 200 kA pot.

  7. Phosphazene additives

    SciTech Connect

    Harrup, Mason K; Rollins, Harry W

    2013-11-26

    An additive comprising a phosphazene compound that has at least two reactive functional groups and at least one capping functional group bonded to phosphorus atoms of the phosphazene compound. One of the at least two reactive functional groups is configured to react with cellulose and the other of the at least two reactive functional groups is configured to react with a resin, such as an amine resin of a polycarboxylic acid resin. The at least one capping functional group is selected from the group consisting of a short chain ether group, an alkoxy group, or an aryloxy group. Also disclosed are an additive-resin admixture, a method of treating a wood product, and a wood product.

  8. Control of coal combustion SO{sub 2} and NO{sub x} emissions by in-boiler injection of CMA. First quarterly project status report, 1 October 1992--31 December 1992

    SciTech Connect

    Levendis, Y.A.; Wise, D.L.

    1992-12-31

    The principal objectives of the proposed research are two-fold: (A) To understand the mechanism and assess the effectiveness of sulfur capture by the chemical calcium magnesium acetate (CMA). And (B) To evaluate the NO{sub x} reduction capabilities of CMA by burning the organic constituents of the chemical (the acetate) and reducing NO to stable N{sub 2} The optimum conditions and the location of CMA introduction in the furnace will be identified. To achieve these goals water solutions of CMA or dry powders of CMA will be injected into hot air or gases simulating the furnace exhaust (containing CO{sub 2}, SO{sub x} NO{sub x}, H{sub 2}O, O{sub 2} etc.) and the composition of gaseous and solid products of the reaction will be monitored. The processes of burning the organic acetate as well as the calcination, sintering and sulfation of the remaining solid will be studied in detail.

  9. Mechanism of Preferential Adsorption of SO>2 into Two Microporous Paddle Wheel Frameworks M(bdc)(ted)0.5

    SciTech Connect

    Tan, Kui; Canepa, Pieremanuele; Gong, Qihan; Liu, Jian; Johnson, Daniel H.; Dyevoich, Allison A.; Thallapally, Praveen K.; Thonhauser, Timo; Li, Jing; Chabal, Y. J.

    2013-12-02

    The adsorption of a corrosive gas, SO>2, into microporous pillared paddle-wheel frameworks M(bdc)(ted)0.5 [M = Ni, , Zn; bdc = 1,4-benzenedicarboxylate; ted=triethylenediamine] is studied by volumetric adsorption measurements and a combination of in-situ infrared spectroscopy and ab initio density functional theory (DFT) calculations. The uptake of SO>2 in M(bdc)(ted)0.5 at room temperature is quite significant, 9.966 mol kg-1(63.8%) at room temperature/1.132 bar, which represents the highest SO>2 uptake so far observed. Two different adsorption species are identified by infrared spectroscopy: one is typical physisorbed SO>2 species, characterized by a modest red shift of S-O stretching bands (36 cm-1 for νas and 7 cm-1 for νs); the other characterized by adsorption bands at 1242 and 1105cm-1 and by a much higher (~150°C) temperature to completely remove. Theoretical calculations including van der Waals interactions (based on vdW-DF) indicate that the adsorption geometry of SO>2 involves one molecule bonding of its sulfur atom to the oxygen atom of the paddle-wheel building unit and its two oxygen atoms to the C-H groups of the organic linkers by formation of hydrogen bonds. Such a configuration results in a large distortion of benzene rings, which is consistent with the experimentally observed shift of the ring deformation mode. The simulated frequency shift of the SO>2 stretching bands by vdW-DF is in excellent agreement with spectroscopically measured value of physisorbed SO>2. The IR absorptions at 1242 and 1105 cm-1 also suggest a stronger adsorption configuration, previously observed in SO>4-like species involving two oxygen atoms of the paddle wheel building units. The adsorption configurations of SO>2 into M(bdc)(ted)0.5 derived by infrared spectroscopy and vdW-DF calculations

  10. Oxidation chemistry of chloric acid in NOx/SOx and air toxic metal removal from gas streams

    SciTech Connect

    Kaczur, J.J.

    1996-12-31

    Chloric acid, HClO{sub 3}, is a new oxidizer which has recently been shown to be an effective agent in the simultaneous removal of NOx and/or SOx from combustion flue gases and various chemical processes, including nitrations and metal pickling. Aqueous chloric acid readily reacts with NO and SO{sub 2} even in dilute solutions at ambient temperatures. Chlorine dioxide, ClO{sub 2}, is formed as a chemical intermediate in the solution phase oxidation reactions. The oxidation by-products of NO include NO{sub 2} and nitric acid. The ClO{sub 2} generated from the solution phase reactions also participates in gas phase oxidation reactions with NO and NO{sub 2}. The combined solution phase and fast gas phase reaction chemistries provide the means for creating a new type of high performance NOx/SOx removal process. Wet scrubber based pilot plant tests have demonstrated up to 99% removal of NO. Additional recent research work has shown that chloric acid is an effective reagent for the removal of air toxic metals, such as elemental mercury, which are present in the waste gas output streams from incinerators, hydrogen from mercury cell chlor-alkali plants, and flue gases of coal-fired power plants. Work in this area is being conducted by Argonne National Laboratories and Olin. This paper discusses the oxidation chemistry of chloric acid and its unique solution and gas phase reactions with NO, SO{sub 2}, and air toxics in wet scrubber type process equipment. 32 refs., 16 figs., 5 tabs.

  11. Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report No. 9, March 1--May 31, 1993

    SciTech Connect

    1993-12-31

    The NOXSO process is a dry, post-combustion flue gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from the flue gas of a coal-fired utility boiler. In the process, the SO{sub 2} is reduced to elemental sulfur and the NO{sub x} is reduced to nitrogen and oxygen. It is predicted that the process can economically remove 90% of the acid rain precursor gases from the flue gas stream in a retrofit or new facility. The objective of the NOXSO Demonstration Project is to design, construct, and operate a flue gas treatment system utilizing the NOXSO process at Ohio Edison`s Niles Plant Unit {number_sign}1. The effectiveness of the process will be demonstrated by achieving significant reductions in emissions of sulfur and nitrogen oxides. In addition, sufficient operating data will be obtained to confirm the process economics and provide a basis to guarantee performance on a commercial scale. Ohio Edison`s Niles Plant Unit {number_sign}1 generates 115 MW of electricity and 275,000 scfm of flue gas while burning 3.5% sulfur coal. The project is presently in the project definition and preliminary design phase. This phase was included in the project to allow completion of process studies and preliminary activities which could be conducted in parallel with NOXSO`s pilot plant project being conducted at Ohio Edison`s Toronto Power Plant.

  12. Studies on the effect of acid treated TiO{sub 2} on the electrical and tensile properties of hexanoyl chitosan-polystyrene-LiCF{sub 3}SO{sub 3} composite polymer electrolytes

    SciTech Connect

    Hanif, Nur Shazlinda Muhammad; Shahril, Nur Syuhada Mohd; Azmar, Amisha; Winie, Tan

    2015-08-28

    Composite polymer electrolytes (CPEs) comprised of hexanoyl chitosan:polystyrene (90:10) blend, lithium triflouromethanesulfonate (LiCF{sub 3}SO{sub 3}) salt and titanium oxide (TiO{sub 2}) filler were prepared by solution casting technique. The TiO{sub 2} fillers were treated with 2% sulphuric acid (H{sub 2}SO{sub 4}) aqueous solution. The effect of acid treated TiO{sub 2} on the electrical and tensile properties of the electrolytes were investigated. Acid treated TiO{sub 2} decreased the electrolyte conductivity. Both the dielectric constant and dielectric loss decrease with increasing frequency and increases with increasing temperature. Relaxation times for ionic carriers were extracted from the loss tangent maximum peak at various temperatures. A distribution of relaxation time implied the non-Debye response. At all frequencies, ac conductivity increases with increasing temperature. An enhancement in the Young’s modulus was observed with the addition of TiO{sub 2}. The Young’s modulus increases with increasing TiO{sub 2} content. This is discussed using the percolation concept.

  13. PHOTOCHEMISTRY IN TERRESTRIAL EXOPLANET ATMOSPHERES. II. H{sub 2}S AND SO{sub 2} PHOTOCHEMISTRY IN ANOXIC ATMOSPHERES

    SciTech Connect

    Hu Renyu; Seager, Sara; Bains, William

    2013-05-20

    Sulfur gases are common components in the volcanic and biological emission on Earth, and are expected to be important input gases for atmospheres on terrestrial exoplanets. We study the atmospheric composition and the spectra of terrestrial exoplanets with sulfur compounds (i.e., H{sub 2}S and SO{sub 2}) emitted from their surfaces. We use a comprehensive one-dimensional photochemistry model and radiative transfer model to investigate the sulfur chemistry in atmospheres ranging from reducing to oxidizing. The most important finding is that both H{sub 2}S and SO{sub 2} are chemically short-lived in virtually all types of atmospheres on terrestrial exoplanets, based on models of H{sub 2}, N{sub 2}, and CO{sub 2} atmospheres. This implies that direct detection of surface sulfur emission is unlikely, as their surface emission rates need to be extremely high (>1000 times Earth's volcanic sulfur emission) for these gases to build up to a detectable level. We also find that sulfur compounds emitted from the surface lead to photochemical formation of elemental sulfur and sulfuric acid in the atmosphere, which would condense to form aerosols if saturated. For terrestrial exoplanets in the habitable zone of Sun-like stars or M stars, Earth-like sulfur emission rates result in optically thick haze composed of elemental sulfur in reducing H{sub 2}-dominated atmospheres for a wide range of particle diameters (0.1-1 {mu}m), which is assumed as a free parameter in our simulations. In oxidized atmospheres composed of N{sub 2} and CO{sub 2}, optically thick haze, composed of elemental sulfur aerosols (S{sub 8}) or sulfuric acid aerosols (H{sub 2}SO{sub 4}), will form if the surface sulfur emission is two orders of magnitude more than the volcanic sulfur emission of Earth. Although direct detection of H{sub 2}S and SO{sub 2} by their spectral features is unlikely, their emission might be inferred by observing aerosol-related features in reflected light with future generation space

  14. Measurement of formaldehyde in clean air

    SciTech Connect

    Neitzert, V.; Seiler, W.

    1981-01-01

    A method for the measurement of small amounts of formaldehyde in air has been developed. The method is based on the derivatization of HCHO with 2.4-Denetrophenylhydragine, forming 2.4-Dentrophylhydragine, measured with GC-ECD-technique. HCHO is preconcentrated using a cryogenic sampling technique. The detection limit is 0.05 ppbv for a sampling volume of 200 liter. The method has been applied for measurements in continental and marine air masses showing HCHO mixing ratios of 0.4--5.0 ppbv and 0.2--1.0 ppbv, respectively. HCHO mixing ratios show diurnal variations with maximum values during the early afternoon and minimum values during the early morning. In continental air, HCHO mixing ratios are positively correlated with CO and SO/sub 2/, indicating anthropogenic HCHO sources which are estimated to be 6--11 x 10/sup 12/g/year/sup -1/ on a global scale.

  15. Scavenging ratios based on inflow air concentrations

    SciTech Connect

    Davis, W.E.; Dana, M.T.; Lee, R.N.; Slinn, W.G.N.; Thorp, J.M.

    1991-07-01

    Scavenging ratios were calculated from field measurements made during April 1985. Event precipitation samples were collected at the surface, but air chemistry measurements in the air mass feeding the precipitation were made from an aircraft. In contrast, ratios calculated in previous studies have used air concentration and precipitation chemistry data from only surface measurements. Average scavenging ratios were calculated for SO{sub 4}{sup 2{minus}}, NO{sub 3}{sup {minus}}, NH{sub 4}{sup +}, total sulfate, total nitrate, and total ammonium for 5 events; the geometric mean of these scavenging ratios were 8.5 {times} 10{sup 5}, 5.6 {times} 10{sup 6}, 4.3 {times} 10{sup 5}, 3.4 {times} 10{sup 5}, 2.4 {times} 10{sup 6}, and 9.7 {times} 10{sup 4}, respectively. These means are similar to but less variable than previous ratios formed using only surface data.

  16. Investigation of SO>3 absorption line for in situ gas detection inside combustion plants using a 4-μm-band laser source.

    PubMed

    Tokura, A; Tadanaga, O; Nishimiya, T; Muta, K; Kamiyama, N; Yonemura, M; Fujii, S; Tsumura, Y; Abe, M; Takenouchi, H; Kenmotsu, K; Sakai, Y

    2016-09-01

    We have investigated 4-μm-band SO>3 absorption lines for in situSO3 detection using a mid-infrared laser source based on difference frequency generation in a quasi-phase-matched LiNbO3 waveguide. In the wavelength range of 4.09400-4.10600 μm, there were strong SO>3 absorption lines. The maximum absorption coefficient at a concentration of 170 ppmv was estimated to be about 3.2×10-5  cm-1 at a gas temperature of 190°C. In coexistence with H2O, the reduction of the SO>3 absorption peak height was observed, which was caused by sulfuric acid formation. We discuss a method of using an SO>3 equilibrium curve to derive the total SO>3 molecule concentration. PMID:27607263

  17. Microbial reduction of SO{sub 2} and NO{sub x} as a means of by-product recovery/disposal from regenerable processes for the desulfurization of flue gas. Technical progress report, March 11, 1993--June 11, 1993

    SciTech Connect

    Sublette, K.L.

    1993-11-01

    There are two basic approaches to addressing the problem of SO{sub 2} and NO{sub x} emissions: (1) desulfurize (and denitrogenate) the feedstock prior to or during combustion; or (2) scrub the resultant SO{sub 2} and oxides of nitrogen from the boiler flue gases. The flue gas processing alternative has been addressed in this project via microbial reduction of SO{sub 2} and NO{sub x} by sulfate-reducing bacteria

  18. Air modeling of industrial area in India

    SciTech Connect

    Kumar, A.

    1996-12-31

    With privatization of power sector to fulfill power demand in India, fossil based power projects are proposed at different locations by Indian and foreign companies. As power industry occupies key role in the economic liberalization, the siting and technology for power plant are relevant in the Indian context, and modeling exercise is wanted for the design of stacks and pollution control measures. A case history is included to demonstrate the use of air quality modeling in prediction, and to delineate mitigation measures. Study has been conducted with Gaussian dispersion model to assess the incremental 24 hour maximum Ground Level Concentrations (GLCs) of SO{sub 2}, NO{sub x}, SPM due to proposed power plant. Stack and emission data, wind velocity, wind direction, temperature, mixing height, and stability classes are used as input parameters to the dispersion model. Maximum 24 hour GLCs of SO{sub 2}, NO{sub x}, and SPM are 30, 53, 2.5 {mu}g/m at 2 km east as down wind direction is from west (35%), south-southwest (25%), and west-northwest (15%). Northeast is the most affected quadrant during summer. Plume loopings are assessed from southeast to northeast directions, with maximum concentration in the east with respect to the site. First plume loop is assessed at 2 km distance, and subsequent loops are assessed with less pollutants concentration under atmospheric stability classes (B-E). High concentration of NO{sub x} has been assessed, which may cause hazardous effect like dense fog, particulate droplets, whereas SO{sub 2} concentration may cause acid raining, acid deposition to the surrounding. Proper air pollution control measures are required to minimize NO{sub x} levels.

  19. Improving urban air quality in China: Beijing case study

    SciTech Connect

    Jiming Hao; Litao Wang

    2005-09-01

    China is undergoing rapid urbanization because of unprecedented economic growth. As a result, many cities suffer from air pollution. Two-thirds of China's cities have not attained the ambient air quality standards applicable to urban residential areas (Grade II). Particulate matter (PM), rather than sulfur dioxide (SO{sub 2}), is the major pollutant reflecting the shift from coal burning to mixed source pollution. In 2002, 63.2 and 22.4% of the monitored cities have PM and SO{sub 2} concentrations exceeding the Grade II standard, respectively. Nitrogen oxides (NOx) concentration kept a relatively stable level near the Grade II standard in the last decade and had an increasing potential in recent years because of the rapid motorization. In general, the air pollutants emission did not increase as quickly as the economic growth and energy consumption, and air quality in Chinese cities has improved to some extent. Beijing, a typical representative of rapidly developing cities, is an example to illustrate the possible options for urban air pollution control. Beijing's case provides hope that the challenges associated with improving air quality can be met during a period of explosive development and motorization. 21 refs., 19 figs., 6 tabs.

  20. Comparative study of the reactions of metal oxides with H{sub 2}S and SO{sub 2}

    SciTech Connect

    Sotirchos, S.V.

    1992-12-31

    Primary objective was to investigate the effects of pore structure on capacity of porous metal oxides for removal of SO{sub 2} from power plant fuel gas and H{sub 2}S from hot coal gas. During this period, a comparative study was carried out on the direct reaction with H{sub 2}S and SO{sub 2} of the three limestones used as CaO precursors: Greer limestone, Georgia marble, and Iceland spar calcite. Sulfation was carried out at 750 and 850 C in a thermogravimetric analysis system under simulated high pressure (enough CO{sub 2} to prevent decomposition of CaCO{sub 3}). Results are presented as conversion vs time graphs. Mercury penetration and gas adsorption were used to analyze the structure. Activation energies and effective diffusivities were determined. A variable diffusivity shrinking-core model was used to analyze the data. In the future, this limestone study will be completed, and a study on supported CuO sorbent will be started.

  1. Comparative study of the reactions of metal oxides with H[sub 2]S and SO[sub 2

    SciTech Connect

    Sotirchos, S.V.

    1992-01-01

    Primary objective was to investigate the effects of pore structure on capacity of porous metal oxides for removal of SO[sub 2] from power plant fuel gas and H[sub 2]S from hot coal gas. During this period, a comparative study was carried out on the direct reaction with H[sub 2]S and SO[sub 2] of the three limestones used as CaO precursors: Greer limestone, Georgia marble, and Iceland spar calcite. Sulfation was carried out at 750 and 850 C in a thermogravimetric analysis system under simulated high pressure (enough CO[sub 2] to prevent decomposition of CaCO[sub 3]). Results are presented as conversion vs time graphs. Mercury penetration and gas adsorption were used to analyze the structure. Activation energies and effective diffusivities were determined. A variable diffusivity shrinking-core model was used to analyze the data. In the future, this limestone study will be completed, and a study on supported CuO sorbent will be started.

  2. Nanocrystalline K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3}: Eu for proton beam dosimetry

    SciTech Connect

    Bahl, Shaila; Lochab, S. P.; Pandey, A.; Aleynikov, V. E.; Molokanov, A.; Kumar, Pratik

    2012-06-05

    This paper investigates the Thermoluminescent response of nanocrystalline K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3}: Eu, prepared by Co-precipitation technique to 150 MeV proton beam. The particle size was calculated to be 45 nm by the broadening of the XRD peaks using Scherrer's formula. Samples in the form of pellets were irradiated by 150 MeV proton beam with dose range of 0.1 Gy to 325 Gy. Thermoluminescence (TL) glow curves of the irradiated samples were recorded and studied. It has been found that the phosphor shows a characteristic single peak at around 420 K. The TL response is linear in the range upto 200 Gy and then saturates for higher doses. The wider linear TL response of nanocrystalline K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3}: Eu and low fading makes it a superior candidate as a dosimeter to be used for detecting the doses of protons beams for its various applications in the field of space, therapy and research.

  3. Magmatic gas source for the stratospheric SO[sub 2] cloud from the June 15, 1991, eruption of Mount Pinatubo

    SciTech Connect

    Westrich, H.R. ); Gerlach, T.M. )

    1992-10-01

    A water-rich magmatic gas phase escaped explosively from Mount Pinatubo on June 15, 1991, taking with it a load of crystalline and molten material sufficient to form pumice and tephra deposits with an estimated total dense-rock-equivalent volume of 3-5 km[sup 3], and carrying in it enough sulfur to form a 20 Mt SO[sub 2] cloud in the stratosphere. Application of the petrologic method for estimating sulfur degassing during the climatic event from the sulfur content of trapped glass inclusions and matrix glasses in the pumice deposits requires an unacceptably large volume of erupted magma to account for SO[sub 2] in the stratospheric cloud. The ubiquitous presence of primary vapor bubbles in glass inclusions and unaltered anhydrite phenocrysts in the pumice suggest that sulfur was present in a separate H[sub 2]O-rich gas phase of the Pinatubo magma before eruption. Thus, for this eruption, and perhaps others, the petrologic method for estimating sulfur degassing is prone to substantial underestimation of sulfur release and the potential climatic impact of past explosive eruptions.

  4. Method for sequestering CO.sub.2 and SO.sub.2 utilizing a plurality of waste streams

    DOEpatents

    Soong, Yee; Allen, Douglas E.; Zhu, Chen

    2011-04-12

    A neutralization/sequestration process is provided for concomitantly addressing capture and sequestration of both CO.sub.2 and SO.sub.2 from industrial gas byproduct streams. The invented process concomitantly treats and minimizes bauxite residues from aluminum production processes and brine wastewater from oil/gas production processes. The benefits of this integrated approach to coincidental treatment of multiple industrial waste byproduct streams include neutralization of caustic byproduct such as bauxite residue, thereby decreasing the risk associated with the long-term storage and potential environmental of storing caustic materials, decreasing or obviating the need for costly treatment of byproduct brines, thereby eliminating the need to purchase CaO or similar scrubber reagents typically required for SO.sub.2 treatment of such gasses, and directly using CO.sub.2 from flue gas to neutralize bauxite residue/brine mixtures, without the need for costly separation of CO.sub.2 from the industrial byproduct gas stream by processes such as liquid amine-based scrubbers.

  5. [Surface studies of absorbents for the removal of SO[sub x] and NO[sub x

    SciTech Connect

    Cooper, B.R.; Montano, P.A.

    1989-01-01

    During this quarter, we continued to study the X-ray absorption spectra of copper compounds. Here we report measurements of the high resolution XANES and EXAFS spectra at the sulfur K-edge (E=2472 eV). Using these results together with the information from other investigations, we attempted to gain a better understanding of the complicated chemical adsorption process taking place on the CuO/Al[sub 2]O[sub 3] surface. In the modeling work we have made a major modification of our methodology that will enable us to treat the adsorption of the SO[sub 2] molecule on the CuO/Al[sub 2]O[sub 3] surface. This involves adoption of a hybrid technique in which we use our previously developed two-dimensional periodic FLMTO technique to model a clean surface, and then use a molecular cluster model to represent the local environment giving changes with the SO[sub 2] adsorption. Experimental Work: The XANES and EXAFS measurements at the sulfur K-edge were carried out on beamline X-19A of the National Synchrotron Light Source (NSLS).

  6. Portland cement for SO/sub 2/ control in coal-fired power plants

    DOEpatents

    Steinberg, M.

    1984-10-17

    A method is described for removing oxides of sulfur from the emissions of fossil fuel combustion by injecting portland cement into the boiler with the fuel, the combustion air, or downstream with the combustion gases. The cement products that result from this method is also described. 1 tab.

  7. Portland cement for SO.sub.2 control in coal-fired power plants

    DOEpatents

    Steinberg, Meyer

    1985-01-01

    There is described a method of removing oxides of sulfur from the emissions of fossil fuel combustion by injecting portland cement into the boiler with the fuel, the combustion air, or downstream with the combustion gases. There is also described the cement products that result from this method.

  8. Catalytic reduction of SO{sub 2} with methane over molybdenum catalyst. Quarterly technical report, September 1, 1994--November 30, 1994

    SciTech Connect

    Wiltowski, T.

    1995-03-01

    One of the primary concerns in coal utilization is the emission of sulfur compounds, especially SO{sub 2}. This project deals with catalytic reduction of SO{sub 2} with methane using molybdenum sulfide catalyst supported on different activated carbons: Darco TRS, Norit ROZ-3, and an activated carbon prepared from Illinois coal IBC-110. The work conducted during this quarter has concentrated on catalyst preparation and characterization along with synthesis of activated carbon from IBC-110 coal, as well as, construction of the apparatus for catalytic tests of SO{sub 2} reduction with methane. It was found that Darco TRS supported catalysts have larger surface area than the pure activated carbon, whereas the impregnation of Norit ROZ-3 did not significantly change the BET surface area. Also, the synthesis of activated carbon support from IBC-110 is in progress.

  9. High temperature membranes for H{sub 2}S and SO{sub 2} separations. Quarterly progress report, July 1, 1993--September 30, 1993

    SciTech Connect

    Winnick, J.

    1993-12-31

    High temperature membrane separation techniques have been applied to gas mixtures involved in coal utilization. For coal gasification, H{sub 2}S has been removed from the syn-gas stream, split into hydrogen which enriches the syn-gas,and sulfur which can be condensed from an inert gas sweep stream. For coal combustion, SO{sub 2} has been separated from the flue gas, with concentrated SO{sub 3} produced as a by-product. Both processes appear economically viable, but each requires fundamental improvements: both the H{sub 2}S and SO{sub 2} cells require more efficient membranes and the H{sub 2}S cell needs a more efficient anode. Membranes will be fabricated by either hot-pressing, impregnation of sintered bodies, or tape casting. Research conducted during the present quarter is highlighted, with an emphasis on progress toward these goals.

  10. Aqueous absorbents and membranes for a new flue gas SO/sub 2/ and NO/sub x/ removal process using electrodialysis for regeneration

    SciTech Connect

    Walker, R.J.; Drummond, C.J.

    1986-01-01

    A proposed process is described for removing SO/sub 2/ and NO/sub x/ simultaneously from power-plant flue gas by passing the gas through a wet scrubber, followed by electrodialysis to remove sulfite and sulfate ions from the scrubbing liquor and thermal stripping to remove NO/sub x/. The sulfite and sulfate ions are used to produce sulfuric acid, while the stripped NO/sub x/ is reburned in the boiler. Preliminary tests of a bench-scale electrodialysis stack are described. Absorption and stripping tests of various aqueous absorbents in a one-meter column are also described; the tests were conducted to screen the absorbents for NO/sub x/ and SO/sub 2/ removal ability. Emphasis was on metal-chelate solutions. The best absorbent tested removed 98% of the NO and 99% of the SO/sub 2/ from simulated flue gas containing 5.9% oxygen.

  11. Combined removal of SO{sub x} and NO{sub x} from flue gas using non-thermal plasma. [Quarterly] technical report, September 1--November 30, 1994

    SciTech Connect

    Dhali, S.K.

    1994-12-31

    The SO{sub 2} removal efficiency was studied for concentration in the range of 333--3000 ppM (parts per million). Since the sulfur content of Illinois coal is high, the SO{sub 2} concentration in typical flue gas is in the high end of the range shown above. With high concentration of SO{sub 2} the removal efficiency decreases. However, the removal scales well with applied voltage, electrode length, and supply frequency. In this period the modeling of the process was also accomplished. The results show that a Townsend-type discharge is more efficient than a streamer type discharge in producing OH and 0 radicals. This explains why UV-irradiation helps the removal efficiency. The details are discussed in the report.

  12. Effects of SO/sub 2/ and/or NO/sub 2/ on native plants of the Mojave Desert and the eastern Mojave-Colorado Desert

    SciTech Connect

    Thompson, C.R.; Kats, G.; Lennox, R.W.

    1980-12-01

    Effects of sulfur dioxide and nitrogen dioxide on plant species taken from the Mojave Desert area were studied. Plants were exposed to the gases at the following concentrations: SO/sub 2/ 2.0, 0.67, and 0.22 ppm/ and NO/sub 2/, 1.0, 0.33, and 0.11 ppm. Fumigation of perennial plants at concentrations of 2.0 ppm SO/sub 2/ and 1.0 ppm NO/sub 2/ caused extensive leaf injury. Although the 2.0 ppm SO/sub 2/ level was more injurious to annual plants, the annuals were not as severely affected by the 1.0 ppm NO/sub 2/ level.

  13. High temperature membranes for H{sub 2}S and SO{sub 2} separations. Quarterly progress report, July 1, 1992--September 30, 1992

    SciTech Connect

    Winnick, J.

    1992-12-31

    High temperature membrane separation techniques have been applied to gas mixtures involved in coal utilization. For coal gasification, H{sub 2}S has been removed from the syn-gas stream, split into hydrogen which enriches the syn-gas, and sulfur which can be condensed from an inert gas sweep stream. For coal combustion, SO{sub 2} has been separated from the flue gas, with concentrated SO{sub 3} produced as a by-product. Both processes appear economically viable but each requires fundamental improvements: both the H{sub 2}S cell and the SO{sub 2} cell require more efficient membranes and the H{sub 2}S cell needs a more efficient anode. Membranes will be fabricated by either hot-pressing, impregnation of sintered bodies, or tape casting. Research conducted during the present quarter is highlighted, with an emphasis on progress towards these goals.

  14. Does weather confound or modify the association of particulate air pollution with mortality? An analysis of the Philadelphia data, 1973--1980

    SciTech Connect

    Samet, J.; Zeger, S.; Kelsall, J.; Xu, J.; Kalkstein, L.

    1998-04-01

    This report considers the consequences of using alternative approaches to controlling for weather and explores modification of air pollution effects by weather, as weather patterns could plausibly alter air pollution`s effect on health. The authors analyzed 1973--1980 total mortality data for Philadelphia using four weather models and compared estimates of the effects of TSP and SO{sub 2} on mortality using a Poisson regression model. Two synoptic categories developed by Kalkstein were selected--The Temporal Synoptic Index (TSI) and the Spatial Synoptic Classification (SSC)--and compared with (1) descriptive models developed by Schwartz and Dockery (S-D); and (2) LOESS, a nonparametric function of the previous day`s temperature and dew point. The authors considered model fit using Akaike`s Information Criterion (AIC) and changes in the estimated effects of TSP and SO{sub 2}. In the full-year analysis, S-D is better than LOESS at predicting mortality, and S-D and LOESS are better than TSI, as measured by AIC. When TSP or SO{sub 2} was fit alone, the results were qualitatively similar, regardless of how weather was controlled; when TSP and SO{sub 2} were fit simultaneously, the S-D and LOESS models give qualitatively different results than TSI, which attributes more of the pollution effect to SO{sub 2} than to TSP. Model fit is substantially poorer with TSI.

  15. Analysis of SO{sub 2} sorption capacity of rice husk ash (RHA)/CaO/NaOH sorbents using response surface methodology (RSM): untreated and pretreated RHA

    SciTech Connect

    Irvan Dahlan; Keat Teong Lee; Azlina Harun Kamaruddin; Abdul Rahman Mohamed

    2008-03-01

    The SO{sub 2} sorption capacity (SSC) of sorbents prepared from rice husk ash (RHA) with NaOH as additive was studied in a fixed-bed reactor. Rice husk ash is produced by burning rice husks at about 300{sup o}C and was chosen as a source of siliceous material, abundantly available in Malaysia. The sorbents were prepared using a water hydration method by slurrying RHA, CaO, and NaOH. Response surface methodology (RSM) based on four-variable central composite face centered design (CCFCD) was employed in the synthesis of the sorbents. The correlation between the sorbent SSC (as response) with four independent sorbent preparation variables, i.e. hydration period, RHA/CaO ratio, NaOH amount, and drying temperature, were presented as empirical mathematical models. Among all the variables studied, the amount of NaOH used was found to be the most significant variable affecting the SSC of the sorbents prepared. The SSC for sorbent prepared with the addition of NaOH was found to be significantly higher than sorbents prepared without NaOH. This is probably because NaOH is a deliquescent material, and its existence increases the amount of water collected on the surface of the sorbent, a condition required for sorbent-SO{sub 2} reaction to occur at low temperature. The effect of further treatment of RHA at 600{sup o}C was also investigated. Although pretreated RHA sorbents demonstrated higher SSC as compared to untreated RHA sorbents, nevertheless, at optimum conditions, sorbents prepared from untreated RHA was found to be more favorable due to practical and economic concerns. 33 refs., 3 figs., 1 tab.

  16. /Air Atmospheres

    NASA Astrophysics Data System (ADS)

    Emami, Samar; Sohn, Hong Yong; Kim, Hang Goo

    2014-08-01

    Molten magnesium oxidizes rapidly when exposed to air causing melt loss and handling difficulties. The use of certain additive gases such as SF6, SO2, and CO2 to form a protective MgO layer over a magnesium melt has been proposed. The oxidation behavior of molten magnesium in air containing various concentrations of SF6 was investigated. Measurements of the kinetics of the oxide layer growth at various SF6 concentrations in air and temperatures were made. Experiments were performed using a thermogravimetric analysis unit in the temperature range of 943 K to 1043 K (670 °C to 770 °C). Results showed that a thin, coherent, and protective MgF2 layer was formed under SF6/Air mixtures, with a thickness ranging from 300 nm to 3 μm depending on SF6 concentration, temperature, and exposure time. Rate parameters were calculated and a model for the process was developed. The morphology and composition of the surface films were studied using scanning electron microscope and energy-dispersive spectroscope.

  17. 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.

  18. Corrosion behavior of carbon steel in the monoethanolamine-H{sub 2}O-CO{sub 2}-O{sub 2}-SO{sub 2} system

    SciTech Connect

    Kladkaew, N.; Idem, R.; Tontiwachwuthikul, P.; Saiwan, C.

    2009-10-15

    The effects of operating parameters on the corrosion of carbon steel in the monoethanolamine (MEA)-H{sub 2}O-CO{sub 2}-O{sub 2}-SO{sub 2} system were investigated using two different corrosion measurement techniques. The corrosion studies were conducted using a 273A potentiostat using MEA, O{sub 2}, and SO{sub 2} concentrations and CO{sub 2} loading in the ranges of 1-7 kmol/m{sup 3}, 0-100%, 0-204 ppm, and 0-0.5 mol CO{sub 2}/mol MEA, respectively, at corrosion temperatures in the range of 303-353 K. The experimental results showed, for the first time, that a higher concentration of SO{sub 2} in a simulated flue gas stream induces a higher corrosion rate essentially because of the increase in the hydrogen ion concentration generated by reactions of SO{sub 2} and H{sub 2}O as well as SO{sub 2}, O{sub 2}, and H{sub 2}O. Also, an increase in oxygen concentration in the simulated flue gas stream causes a higher corrosion rate due to the increasing solubility of oxygen and, in turn, a higher amount of dissolved oxygen in the liquid phase. The results further show that an increase in the concentrations of MEA, O{sub 2}, and SO{sub 2} as well as CO{sub 2} loading will cause the generation of higher amounts of hydrogen or hydronium ions, as well as carbonic acid and bicarbonate ions, and this is what leads to a higher corrosion rate.

  19. Air Pollution

    MedlinePlus

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, dust, ... a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

  20. Air Pollution

    MedlinePlus

    Air pollution is a mixture of solid particles and gases in the air. Car emissions, chemicals from factories, ... Ozone, a gas, is a major part of air pollution in cities. When ozone forms air pollution, it's ...

  1. Evaluation of official air sampling methodologies in Ukraine

    SciTech Connect

    Nakonechniy, J.J.; Wadden, R.A.; Scheff, P.A.; Suero, M.

    1997-12-31

    In conjunction with an environmental epidemiology study of the health of Ukrainian children, a significant amount of air pollution measurement data was gathered from government agencies. The areas of interest were the industrial city of Dneprodzherzhinsk; and the Dniprovsky region of Kyiv. The data were for 1993 and, for some of the monitoring stations, 1994. The pollutants reported included dust (approximately equivalent to TSP, total suspended particulate matter), SO{sub 2}, CO, NO{sub 2}, NO, H{sub 2}S, phenol, HCl, NH{sub 3}, formaldehyde, BaP, and lead. The ultimate goal was to evaluate whether existing historical data are appropriate for developing measures of human exposure. In order to evaluate the data it was necessary to understand the sampling and analytical methodologies which were used. Small sample volumes coupled with dated analytical procedures resulted in very poor precision and detection limits for most of the measured pollutants. The measurement of particulate matter is a good example of the limits imposed by the sampling methodology. The short sample time (20 min), small sample volume (150 lpm), and limited analytical balances (0.5 mg resolution) result in a minimum lower limit of detection of 0.25 mg/m{sup 3}. For example at Kyiv Station 3 in 1993, only one of 545 measurements exceeded 0.2 mg/m{sup 3}. This minimum detectable quantity is over three times the former US annual TSP standard. In addition, even when operated on a 24-hour basis in the US, it has been shown that the sampling method only collected approximately 34% of that collected by a co-located hi-vol sampler. Consequently, official air pollution data for suspended dust are likely to severely under-represent actual ambient concentrations. Data for other pollutants are presented and sampling and analytical methods are similarly compared with Western methods in common use.

  2. Influence of self heating and Li{sub 2}SO{sub 4} addition on the microstructural development of calcium aluminate cement

    SciTech Connect

    Gosselin, Christophe Gallucci, Emmanuel; Scrivener, Karen

    2010-10-15

    Hydrated Calcium Aluminate Cement (CAC) is known to have a complex microstructure involving different phase assemblages strongly dependant on the temperature. This work presents an experimental approach to study the microstructure of CAC pastes from the first minute of hydration with controlled time-temperature histories up to several months of curing. The self heating usually occurring in the CAC concrete is considered and its influence on the growth and assemblage of the hydration products and subsequent space filling is shown. Quantification of the degree of CA hydration by BSE image analysis is used to understand the evolution of phases throughout the hydration process. Lithium sulphate is commonly used to control the setting time of CAC based materials. It is shown that this promotes the formation of more stable hydrates, but slightly reduces the extent of CA hydration.

  3. Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report No. 13, March 1, 1994--May 31, 1994

    SciTech Connect

    1994-12-31

    The NOXSO process is a dry, post-combustion flue gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from the flue gas of a coal-fired utility boiler. In the process, the SO{sub 2} is converted to a sulfur by-product and the NO{sub x} is converted to nitrogen and oxygen. It is predicted that the process can economically remove 90% of the acid rain precursor gases from the flue gas stream in a retrofit or new facility. The objective of the NOXSO Demonstration Project is to design, construct, and operate a flue gas treatment system utilizing the NOXSO process. The effectiveness of the process will be demonstrated by achieving significant reductions in emissions of sulfur and nitrogen oxides. In addition, sufficient operating data will be obtained to confirm the process economics and provide a basis to guarantee performance on a commercial scale. The project is presently in the project definition and preliminary design phase. Data obtained during pilot plant testing which was completed on July 30, 1993 is being incorporated in the design of the commercial size plant. A suitable host site to demonstrate the NOXSO process on a commercial scale is presently being sought. Preliminary engineering activities involved evaluating various design options for the major process vessels with the principal focus being on the sorbent heater vessel, which is operated at the highest temperature. Additionally, the impact of the NOXSO system on power plant particulate emissions and opacity was estimated. It is predicted that particulate emissions will decrease slightly while opacity will increase slightly. Neither change will be significant enough to have an impact on emissions compliance. Advertised performance of the proposed adsorber separator is being verified by laboratory testing. Process studies activities included POC equipment inspection and materials evaluations.

  4. Syntheses, crystal structures and optical spectroscopy of Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) and Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O

    SciTech Connect

    Kazmierczak, Karolina; Hoeppe, Henning A.

    2011-05-15

    The lanthanide sulphate octahydrates Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) and the respective tetrahydrate Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O were obtained by evaporation of aqueous reaction mixtures of trivalent rare earth oxides and sulphuric acid at 300 K. Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) crystallise in space group C2/c (Z=4, a{sub Ho}=13.4421(4) A, b{sub Ho}=6.6745(2) A, c{sub Ho}=18.1642(5) A, {beta}{sub Ho}=102.006(1) A{sup 3} and a{sub Tm}=13.4118(14) A, b{sub Tm}=6.6402(6) A, c{sub Tm}=18.1040(16) A, {beta}{sub Tm}=101.980(8) A{sup 3}), Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O adopts space group P2{sub 1}/n (a=13.051(3) A, b=7.2047(14) A, c=13.316(3) A, {beta}=92.55(3) A{sup 3}). The vibrational and optical spectra of Ho{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O and Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O are also reported. -- Graphical abstract: In the lanthanide sulphate octahydrates the cations form slightly undulated layers. Between the layers are voids in which sulphate tetrahedra and water molecules are located. The holmium compound exhibits an Alexandrite effect. Display Omitted Highlights: {yields} Determination of the optimum conditions for the growth of single-crystals of Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) and Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O. {yields} Single-crystal structure elucidation of Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) including hydrogen bonds. {yields} Single-crystal structure determination of Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O including hydrogen bonds. {yields} UV-vis spectra of Ho{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O and Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O recorded and interpreted: Assignation of bands and clarification of the Alexandrite effect of the Ho compound. {yields} IR and Raman spectra of Ln{sub 2}(SO{sub 4}){sub 3}.8H{sub 2}O (Ln=Ho, Tm) and Pr{sub 2}(SO{sub 4}){sub 3}.4H{sub 2}O recorded and interpreted.

  5. Method for simultaneously removing SO.sub.2 and NO.sub.X pollutants from exhaust of a combustion system

    DOEpatents

    Levendis, Yiannis A.; Wise, Donald L.

    1994-05-17

    A method is disclosed for removing pollutants from the exhaust of combustion systems burning fuels containing substantial amounts of sulfur and nitrogen. An exemplary method of the invention involves the formation and reaction of a sorbent comprising calcium magnesium acetate (CMA). The CMA is either dry-sprayed (in the form of a fine powder) or wet-sprayed in an aqueous solution in a high temperature environment such as a combustion chamber. The latter technique is feasible since CMA is a uniquely water-soluble form of calcium and magnesium. When the dispersed particles of CMA are heated to a high temperature, fine calcium and magnesium oxide particles, which are hollow with thin and highly porous walls are formed, affording optimum external and internal accessibility for reacting with toxic gaseous emissions such as SO.sub.2. Further, the combustion of the organic acetate portion of the sorbent results in the conversion of NO.sub.x to N.sub.2.

  6. Studies on the effect of Li{sub 2}SO{sub 4} on the structure of lithium borate glasses

    SciTech Connect

    Ganguli, M.; Rao, K.J.

    1999-02-11

    Thermal and spectroscopic investigations have been carried out on a number of glasses with a wide range of compositions in the pseudoternary glass system, Li{sub 2}SO{sub 4}-Li{sub 2}O-B{sub 2}O{sub 3}, to understand the role of sulfate ions in modifying the borate glass structure. Both nuclear magnetic resonance (NMR) and infrared (IR) spectroscopic results indicate that four-coordinate boron atoms are retained in the glass structure to a greater extent in sulfate-containing glasses than in pure lithium borate glasses. There seems to be some evidence for the existence of sulfoborate-type units in Raman spectra in the region of 800--960 cm{sup {minus}1}. These conclusions are supported by the observed behavior of glass transition temperatures and molar volumes. The possibility of formation of sulfoborate-type units is discussed from bonding and thermodynamic points of view.

  7. SO{sub 2} and NOx trading markets: providing flexibility and results

    SciTech Connect

    Sam Napolitano; Melanie LaCount; Daniel Chartier

    2007-06-15

    Experience with the Acid Rain and NOx Budget Trading Programs demonstrates that cap-and-trade programs are an effective means of achieving broad improvements in air quality. Results demonstrate that the combination of mandatory emissions caps, a viable allowance trading market, rigorous emissions monitoring and reporting protocols, and automatic enforcement provide accountability and ensure results in a cost-effective manner. The market developments discussed in this article demonstrate a successful environmental partnership. With a government focused on results and a private sector motivated to innovate, cap-and trade systems deliver environmental results as efficiently and effectively as possible. 3 refs., 4 figs,

  8. Assessing the air pollution carrying capacity of the northern Puget Sound region: an application of TAPAS

    SciTech Connect

    Wood, M.C.; Childs J.E.; Marlatt, W.E.

    1980-09-01

    The technique discussed, the Topographic Air Pollution Analysis System (TAPAS), was developed to provide valid information on the dispersion capability of the lower atmosphere in areas characterized by complex terrain features. A study was undertaken to assess the air quality (SO/sub 2/) impacts associated with energy development in the region and to determine the constraints on energy development due to regulated limitations on the amount of air quality degradation allowable in the area. The emission constraint analysis for the northern Puget Sound region indicated that total SO/sub 2/ emissions in the core area (on an annual basis) are less than half of the amount that could be tolerated in the entire core region while maintaining ambient concentrations within state and federal annual average limitations. However, comparison of source characteristics with source location and grid cell emission restrictions indicated that localized areas adjacent to the major point sources are already far in excess of the SO/sub 2/ carrying capacity. This conclusion is supported by air quality monitoring data that indicate state standard violations at several receptor locations within the study area. The annual maps of wind patterns and PI-Matrix values show areas of both good and poor dispersion characteristics under the most prevalent flow conditions.

  9. Evaluation of the Community Multiscale Air Quality (CMAQ) modeling system against size-resolved measurements of inorganic particle composition across sites in North America

    EPA Science Inventory

    This work evaluates particle size-composition distributions simulated by the Community Multiscale Air Quality (CMAQ) model using Micro-Orifice Uniform Deposit Impactor (MOUDI) measurements at 18 sites across North America. Size-resolved measurements of particulate SO>4<...

  10. Design and development of a self-regenerative contained-liquid membrane process for combined SO{sub x} and NO{sub x} removal. Final report

    SciTech Connect

    Varanasi, S.; LeBlanc, S.E.

    1992-11-01

    The lack of an efficient, cost effective process for the removal of sulfur compounds from gas streams (either gasified coal or flue gases resulting from coal combustion) is a major obstacle to the economic utilization of high sulfur Ohio coal. The most economically favorable processes for the desulfurization of flue gases are the regenerable processes as opposed to the `throwaway` processes. In addition, recovery of sulfur from these gases in the form of elemental sulfur or H{sub 2}SO{sub 4} does seem to be an essential step in the economic utilization of high sulfur coal. n light of these observations, a recently proposed FGD process which regenerates the scrubbing liquor ``in-situ`` as well as recovering a concentrated S0{sub 2} stream for use in sulfuric acid production, is quite promising. Conventional processes, presently in operation, employ large packed tower scrubbers for S0{sub 2} absorption which results in very high capital expenditures and operating costs. Recent developments in membrane technology can now provide us with an alternative to these large packed towers for stack gas cleanup. In this research we have investigated the use of novel membrane contactors for replacing more conventional packed absorbers. Contained-liquid membranes, exploiting carrier mediated transpose, enable the scrubbing liquid to be regenerated ``in-site,`` in a single process unit. Microporous single-ply polymeric membranes have recently been used in gas-liquid and liquid-liquid contactors. These membranes are fashioned into a tubular shape (i.e. long, thin fibers) for use in mass transfer contactors.

  11. Thermodynamic Model for the Solubility of Ba(SeO4, SO>4) Precipitates

    SciTech Connect

    Rai, D.; Felmy, Andrew R.; Moore, Dean A.; Kitamura, Akira; Yoshikawa, Hideki; Doi, Reisuke; Yoshida, Yasushi

    2014-08-15

    The solubility of Ba(SeO4, SO>4) precipitates was determined as a function of the BaSeO4 mole fractions, ranging from 0.0015 to 0.3830, and time with an equilibration period extending to as long as 302 days. Equilibrium/steady state conditions in this system are reached in ≤ 65 days. Pitzer’s ion interaction model was used to calculate solid and aqueous phase activity coefficients. Thermodynamic analyses showed that the data do not satisfy Gibbs-Duhem equation, thereby demonstrating that a single-solid solution phase does not control both the selenate and sulfate concentrations. Our extensive data with log 10 [Ba] ranging from -3.6 to -5.9 mol kg-1, log 10 [SeO4] rangingfrom-3.6 to -5.2 mol kg-1, and log 10 [SO>4] ranging from-4.0 to -5.3 mol kg-1 can be explained with the formation of an ideal BaSeO4 solid solution phase that controls the selenium concentrations and a slightly disordered/less-crystalline BaSO4(s) (log 10Κ°sp = -9.5 instead of -10.05 for barite) that controls the sulfate concentrations. In these experiments the BaSO4 component of the solid solution phase never reaches thermodynamic equilibrium with the aqueous phase. Thermodynamic interpretations of the data show that both the ideal BaSeO4 solid solution phase and less-crystalline BaSO4 (s) phase are in equilibrium with each other in the entire range of BaSeO4 mole fractions investigated in this study.

  12. The effect of additives on lime dissolution rates. Final report

    SciTech Connect

    Khang, S.J.

    1996-07-31

    Based on the previous years` studies concerning the efficiency of SO{sub 2} removal by spray dryers with high sulfur coal flue gas, the work for year five included investigations of lime dissolution rates at different slaking conditions and with the effect of additives. The prominent additives that have significant effects on lime dissolution rates were tested with the mini pilot spray drying absorber to see their effects on spray drying desulfurization applications. The mechanisms of these additive effects along with the properties of hygroscopic additives have been discussed and incorporated into the spray drying desulfurization model ``SPRAYMOD-M.`` Slaking conditions are very important factors in producing high quality lime slurry in spray drying desulfurization processes. At optimal slaking conditions, the slaked lime particles are very fine (3-5{mu}m) and the slaked lime has high BET surface areas which are beneficial to the desulfurization. The slaked lime dissolution rate experiments in our study are designed to determine how much lime can dissolve in a unit time if the initial lime surface area is kept constant. The purpose of the dissolution rate study for different additives is to find those effective additives that can enhance lime dissolution rates and to investigate the mechanisms of the dissolution rate enhancement properties for these additives. The applications of these additives on spray drying desulfurization are to further verify the theory that dissolution rate is a rate limiting step in the whole spray drying desulfurization process as well as to test the feasibility of these additives on enhancing SO{sub 2} removal in spray dryers.

  13. Complex peroxyuranates. Synthesis and structural assessment of alkali-metal and ammonium dioxoperoxy(sulfato)aquouranates(VI), A/sub 2/(UO/sub 2/(O/sub 2/)SO/sub 4/(H/sub 2/O)) (A = NH/sub 4/, Na), and alkali-metal and ammonium dioxoperoxy(oxalato)uranate(VI) hydrates, A/sub 2/(UO/sub 2/(O/sub 2/)C/sub 2/O/sub 4/). H/sub 2/O

    SciTech Connect

    Bhattacharjee, M.; Chaudhuri, M.K.; Purkayastha, R.N.D.

    1986-07-02

    Yellow microcrystalline alkali-metal and ammonium dioxoperoxy(sulfato)aquouranates(VI), A/sub 2/(UO/sub 2/(O/sub 2/)SO/sub 4/(H/sub 2/O)) (A = NH/sub 4/, Na), and alkali-metal and ammonium dioxoperoxy(oxalato)uranate(VI) hydrates, A/sub 2/(UO/sub 2/(O/sub 2/)C/sub 2/O/sub 4/).H/sub 2/O (A = NH/sub 4/, Na, K), have been synthesized from the reaction of the product obtained by treating an aqueous solution of UO/sub 2/(NO/sub 3/)/sub 2/.6H/sub 2/O with alkali-metal or ammonium hydroxide, AOH, with 30% H/sub 2/O/sub 2/ and aqueous sulfuric acid and oxalic acid solution, respectively, in the mole ratio UO/sub 2/(NO/sub 3/)/sub 2/.6H/sub 2/O:H/sub 2/O/sub 2/:SO/sub 4//sup 2 -/ or C/sub 2/O/sub 4//sup 2 -/ of 1:111:5 or 1, at pH 6 maintained by the addition of the corresponding alkali-metal or ammonium hydroxide. Precipitation was completed by the addition of ethanol. IR and laser Raman spectra suggest that the O/sub 2//sup 2 -/ and SO/sub 4//sup 2 -/ ions in (UO/sub 2/(O/sub 2/)SO/sub 4/(H/sub 2/O))/sup 2 -/ are bonded to the UO/sub 2//sup 2 +/ center in a bridging and in a monodentate manner, respectively, while both the O/sub 2//sup 2 -/ and C/sub 2/O/sub 4//sup 2 -/ ions in (UO/sub 2/(O/sub 2/)C/sub 2/O/sub 4/)/sup 2 -/ bind the uranyl center in bidentate chelated fashion. The complex peroxyuranates are diamagnetic and insoluble. The A/sub 2/(UO/sub 2/(O/sub 2/)SO/sub 4/(H/sub 2/O)) compounds, unlike A/sub 2/(UO/sub 2/(O/sub 2/)C/sub 2/O/sub 4/).H/sub 2/O, are stable up to 110 /sup 0/C. Whereas H/sub 2/O in A/sub 2/(UO/sub 2/(O/sub 2/SO/sub 4/(H/sub 2/O)) is coordinated to the UO/sub 2//sup 2 +/ center, it occurs as a water of crystallization in the corresponding peroxy oxalato compounds. 20 references, 3 tables.

  14. Multi-heat addition turbine engine

    NASA Technical Reports Server (NTRS)

    Franciscus, Leo C. (Inventor); Brabbs, Theodore A. (Inventor)

    1993-01-01

    A multi-heat addition turbine engine (MHATE) incorporates a plurality of heat addition devices to transfer energy to air and a plurality of turbines to extract energy from the air while converting it to work. The MHATE provides dry power and lower fuel consumption or lower combustor exit temperatures.

  15. CRADA Final Report For CRADA NO. CR-12-006 [Operation and Testing of an SO{sub 2}-depolarized Electrolyzer (SDE) for the Purpose of Hydrogen and Sulfuric Acid Production

    SciTech Connect

    Summers, W. A.; Colon-Mercado, H. R.; Steimke, J. L.; Zahn, Steffen

    2014-02-24

    Over the past several years, Savannah River National Laboratory (SRNL) has led a team of collaborators under the Department of Energy’s (DOE) nuclear hydrogen production program to develop the Hybrid Sulfur (HyS) Process. HyS is a 2-step water-splitting process consisting of high temperature decomposition of sulfuric acid to generate SO{sub 2}, followed by the electrolysis of aqueous SO{sub 2} to generate hydrogen and sulfuric acid. The latter is fed back into the high temperature reactor. SRNL designed and built an SO{sub 2}-depolarized electrolyzer (SDE) and a test facility. Over 40 SDE’s were tested using different catalysts, membranes and other components. SRNL demonstrated that an SDE could be operated continuously for approximately 200 hours under certain conditions without buildup of sulfur at the SDE’s cathode, thus solving a key technical problem with SDE technology. Air Products and Chemicals, Inc. (APCI) is a major supplier of hydrogen production systems, and they have proprietary technology that could benefit from the SDE developed by SRNS, or some improved version thereof. However, to demonstrate that SRNL’s SDE is a truly viable approach to the electrolyzer design, continuous operation for far greater periods of time than 200 hours must be demonstrated, and the electrolyzer must be scaled up to greater hydrogen production capacities. SRNL and Air Products entered into a Cooperative Research and Development Agreement with the objective of demonstrating the effectiveness of the SDE for hydrogen and sulfuric acid production and to demonstrate long-term continuous operation so as to dramatically increase the confidence in the SDE design for commercial operation. SRNL prepared a detailed technical report documenting previous SDE development, including the current SDE design and operating conditions that led to the 200-hour sulfurfree testing. SRNL refurbished its single cell SDE test facility and qualified the equipment for continuous operation. A

  16. Cross-flow, filter-sorbent-catalyst for particulate, SO{sub 2} and NO{sub x} control. Final report

    SciTech Connect

    Benedek, K.; Flytzani-Stephanopoulos, M.

    1994-05-01

    This report describes work performed on a new concept for integrated pollutant control: An active filter comprised of layered, gas permeable membranes that act as a particle filter, an SO{sub 2} sorbent, and a NO{sub x}, reduction catalyst. The focus of the research program documented in this final report is the development of the sorbent/catalyst materials that are the basis of such an emission control system. The device investigated in this program will simultaneously remove particulates, SO{sub 2} and NO{sub x}, from combustion exhaust gases. Sulfur dioxide capture and nitrogen oxide reduction are achieved with a reg le, mixed-metal oxide sorbent-catalyst. The device is a filter with layered walls: A small-pore layer is a barrier to particles, and a macroporus active layer is a SO{sub 2} sorbent and a catalyst for the selective catalytic reduction of NO{sub x}. The small-pore layer could be an inert ceramic that provides structural strength to the unit and protects the active (sorbent-catalyst) material from abrasion or contamination from fly ash particles. We have found that 95--100% removal efficiency of SO{sub 2} and 60--90% removal of NO{sub x}, is achievable with the use of mixed-metal oxide sorbent-catalysts in the device. The ceramic filters are barriers to particles and typically have removal efficiencies of 99.9%.

  17. Pilot-scale testing of a new sorbent for combined SO{sub 2}/NO{sub x} removal. Final report

    SciTech Connect

    Nelson, S. Jr.

    1994-06-01

    A new regenerable sorbent concept for SO{sub 2} and NOx removal was pilot-tested at Ohio Edison`s Edgewater generating station at a 1.5 to 2-MW(e) level. A radial panel-bed filter of a new dry, granular sorbent was exposed to flue gas and regenerated in an experimental proof-of-concept program. The project was successful in demonstrating the new sorbent`s ability to achieve 90% SO{sub 2} removal, 30% NOx removal, and over 80% removal of residual particulates with realistic approach temperatures and low pressure drops. Based on the results of this project, the retrofit cost of this technology is expected to be on the order of $400 per ton of SO{sub 2} and $900 per ton of NOx removed. This assumes that gas distribution is even and methane regeneration is used for a 30% average utilization. For a 2.5%-sulfur Ohio coal, this translates to a cost of approximately $17 per ton of coal. Two by-product streams were generated in the process that was tested: a solid, spent-sorbent stream and a highly-concentrated SO{sub 2} or elemental-sulfur stream. While not within the scope of the project, it was found possible to process these streams into useful products. The spent sorbent materials were shown to be excellent substrates for soil amendments; the elemental sulfur produced is innocuous and eminently marketable.

  18. Effects of exposure to NO{sub 2} or SO{sub 2} on bronchopulmonary reaction induced by Candida albicans in guinea pigs

    SciTech Connect

    Kitabatake, Masayoshi; Yamamoto, Hidetaka; Yuan, Piao Feng

    1995-09-01

    The effects of NO{sub 2} or SO{sub 2} on the bronchopulmonary reactions induced by Candida albicans in guinea pigs were evaluated. Thirty-six guinea pigs (3 groups of 12 animals each) were sensitized with intraperitoneal injection of 10 mg of C. albicans, given twice. Two groups of animals were exposed to about 5 ppm of NO{sub 2} or SO{sub 2} for 4 h/d, 5 d/wk; this exposure was conducted a total of 30 times during the study. The third group served as the control and was not exposed to these pollutants. Two weeks after the second sensitization, all the animals were subjected to inhalation exposure to C. albicans. For 42 h after the antigen challenge, the respiratory rates and expiration/inspiration ratios of the animals were automatically monitored. The number of animals showing tachypnea was significantly higher in the NO{sub 2} exposure group than in the control from 15 h after antigen challenge. In the SO{sub 2} exposure group, the number of animals showing prolonged expiration or prolonged inspiration, or both, was significantly higher than that in the control group, and the symptoms were observed from approximately 15 h after antigen challenge. These findings showed that delayed-type dyspneic symptoms in guinea pigs were increased by exposure to NO{sub 2} or SO{sub 2}, although the symptoms and degree of dyspnea were different for the two gases. 29 refs., 2 figs., 2 tabs.

  19. Phase transformation of Ca{sub 4}[Al{sub 6}O{sub 12}]SO{sub 4} and its disordered crystal structure at 1073 K

    SciTech Connect

    Kurokawa, Daisuke; Takeda, Seiya; Colas, Maggy; Asaka, Toru; Thomas, Philippe; Fukuda, Koichiro

    2014-07-01

    The phase transformation of Ca{sub 4}[Al{sub 6}O{sub 12}]SO{sub 4} and the crystal structure of its high-temperature phase were investigated by differential thermal analysis, temperature-dependent Raman spectroscopy and high-temperature X-ray powder diffraction (CuKα{sub 1}). We determined the starting temperature of the orthorhombic-to-cubic transformation during heating (=711 K) and that of the reverse transformation during cooling (=742 K). The thermal hysteresis was negative (=−31 K), suggesting the thermoelasticity of the transformation. The space group of the high temperature phase is I4{sup ¯}3m with the unit-cell dimensions of a=0.92426(2) nm and V=0.78955(2) nm{sup 3} (Z=2) at 1073 K. The initial structural model was derived by the direct methods and further refined by the Rietveld method. The final structural model showed the orientational disordering of SO{sub 4} tetrahedra. The maximum-entropy method-based pattern fitting method was used to confirm the validity of the split-atom model, in which conventional structure bias caused by assuming intensity partitioning was minimized. At around the transformation temperature during heating, the vibrational spectra, corresponding to the Raman-active SO{sub 4} internal stretching mode, showed the continuous and gradual change in the slope of full width at half maximum versus temperature curve. This strongly suggests that the orthorhombic-to-cubic phase transformation would be principally accompanied by the statistical disordering in orientation of the SO{sub 4} tetrahedra, without distinct dynamical reorientation. - Graphical abstract: (Left) Three-dimensional electron-density distributions of the SO{sub 4} tetrahedron with the split-atom model, and (right) a bird's eye view of electron densities on the plane parallel to (111). - Highlights: • Crystal structure of Ca{sub 4}[Al{sub 6}O{sub 12}]SO{sub 4} at 1073 K is determined by powder XRD. • The atom arrangements are represented by the split-atom model

  20. Environmental performance of air staged combustor with flue gas recirculation to burn coal/biomass

    SciTech Connect

    Anuar, S.H.; Keener, H.M.

    1995-12-31

    The environmental and thermal performance of a 1.07 m diameter, 440 kW atmospheric fluidized bed combustor operated at 700{degrees}C-920{degrees}C and burning coal was studied. Flue gas recirculation was incorporated to enhance the thermal performance and air staging was used to control emissions of SO{sub 2}, CO, NO{sub x} and N{sub 2}O. Studies focused on the effect of excess air, firing rate, and use of sorbent on system performance. The recirculation-staging mode with limestone had the highest thermal efficiency (0.67) using the firing equation. Emission data showed that flue gas recirculation (ratio of 0.7) significantly reduced NO{sub x} emissions; and that use of limestone sorbent at a Ca/S ratio of 3 reduced SO{sub 2} emissions by 64% to approximately 0.310 g/MJ.

  1. The price of pollution: A dual approach to valuing SO{sub 2} allowances

    SciTech Connect

    Coggins, J.S.; Swinton, J.R.

    1996-01-01

    Beginning in 1995, Title IV of the 1990 Clean Air Act Amendments dramatically reduces emissions of sulfur dioxide from US coal burning electric utilities. To achieve this reduction at the lowest possible cost, the law also creates a national market for sulfur dioxide allowances. This paper introduces into the sulfur dioxide compliance literature a method developed by Fare and Gorsskopf for use in deducing the price of a pollutant from plant-level data on the underlying technical relationship between inputs and multiple outputs. An estimate of the average shadow price of sulfur dioxide abatement for Wisconsin coal-burning electric plants is also provided, and this price could be interpreted as the value of an allowance to the plants in the study.

  2. Modeling of SO/sub 2/ oxidation in smog. Final report

    SciTech Connect

    Miller, D.F.

    1981-06-01

    Smog chamber experiments were conducted to investigate the (1) kinetics of free radical reactions of SO2 in smog and (2) SO2 transformation to sulfate for atmospheric simulations. Rate constants were derived for the following reactions: SO2+HO+M yields sulfate (60), SO2+HO2 yields sulfate (61), SO2+CH3O2 yields sulfate (64); k(60) = 1600 k(61 less than 0.2, k(64) less than 0.8 ppm min. Oxidation of SO2 by HO led exclusively to particulate sulfate. Even under favorable NOx conditions, particulate nitrate was not a product. Hydrocarbon mixtures typical of urban environments promoted SO2 oxidation faster than hydrocarbons selected to represent rural conditions. Maximum rates of SO2 oxidation occurred during periods of peak NO2 formation. SO2 oxidation rates for aged smog were 25-35% of the maximum values. Model calculations indicated that reaction 60 dominates sulfate production from SO2 in polluted air. Models that adequately estimate (HO) in smog should suffice to approximate the conversion rates. The model used in this study indicated that SO2 oxidation depends strongly on solar radiation intensity and pollutant conditions. For clear-sky and a variety of HC-NOx conditions, maximum SO2 conversion rates ranged from 3.7-7.4%/hr. Models used to simulate reactions in power plant plumes showed that SO2 oxidation is strongly dependent on plume dispersion rates coupled to the same parameters governing SO2 oxidation in ambient air. Generally the rates of SO2 oxidation in plumes are bound by the ambient rates, although exceptions will occur for certain HC-NOx conditions.

  3. Kinetics of the reaction of iron blast furnace slag/hydrated lime sorbents with SO{sub 2} at low temperatures: effects of the presence of CO{sub 2}, O{sub 2}, and NOx

    SciTech Connect

    Liu, C.F.; Shih, S.M.

    2009-09-15

    The effects of the presence of CO{sub 2}, O{sub 2}, and NOx in the flue gas on the kinetics of the sulfation of blast furnace slag/hydrated lime sorbents at low temperatures were studied using a differential fixed-bed reactor. When O{sub 2} and NOx were not present simultaneously, the reaction kinetics was about the same as that under the gas mixtures containing SO{sub 2}, H{sub 2}O, and N{sub 2} only, being affected mainly by the relative humidity. The sulfation of sorbents can be described by the surface coverage model and the model equations derived for the latter case. When both O{sub 2} and NOx, were present, the sulfation of sorbents was greatly enhanced, forming a great amount of sulfate in addition to sulfite. The surface coverage model is still valid in this case, but the model equations obtained show a more marked effect of relative humidity and negligible effects of SO{sub 2} concentration and temperature on the reaction. The effect of sorbent composition on the reaction kinetics was entirely represented by the effects of the initial specific surface area (S{sub g0}) and the Ca molar content (M{sup -1}) of sorbent. The initial conversion rate of sorbent increased linearly with increasing S{sub g0}, and the ultimate conversion increased linearly with increasing S{sub g0}M{sup -1}. The model equations obtained in this work are applicable to describe the kinetics of the sulfation of the sorbents in the low-temperature dry and semidry fine gas desulfurization processes either with an upstream NOx, removal unit or without.111

  4. Update on performance tests from the COBRA Process, a combined SO{sub 2} and NO{sub x} removal system[Copper Oxide Bed Regenerable Adsorber

    SciTech Connect

    Breault, R.W.; Litka, T.

    1999-07-01

    The Low Emission Boiler System (LEBS) Program of the US Department of Energy (DOE) is developing advanced power systems to accelerate the commercialization of affordable, highly efficient, and low-emission pulverized coal-fueled electric generating technologies. DB Riley Inc.'s concept for LEBS includes a dry, regenerable flue gas desulfurization and denitrification process. The COBRA (Copper Oxide Bed Regenerable Adsorber) Process can efficiently remove sulfur dioxide (SO{sub 2}) and sulfur trioxide (SO{sub 3}) and reduce nitrogen oxides (NO{sub x}) from flue gas with no solid or liquid byproducts and at a competitive cost. The sulfur laden flue gas is contacted with copper oxide impregnated alumina substrate in a cross flow moving bed reactor operating at 700 F. Sulfur dioxide reacts with the copper to form copper sulfate and the copper oxide/copper sulfate bed acts as a selective catalyst for NO{sub x} reduction. The sulfated sorbent is transported from the bottom of the moving bed reactors to the regenerator vessels where methane is used to reduce the copper sulfate to copper and SO{sub 2}. The concentrated SO{sub 2} stream resulting from regeneration may be oxidized to SO{sub 3} and condensed to sulfuric acid or can be converted to elemental sulfur in a Claus Plant or scrubbed with ammonia to form an ammonium sulfate. This paper will present the results of performance testing conducted on a 1 MW Pilot Scale Facility located at the Illinois Coal Development Park. This facility was designed and built to demonstrate at a reasonable scale the component configurations to be utilized in a full-scale system and to verify and optimize the operation of the integrated system. The ability of laboratory tests, when combined with a model of the moving bed adsorber, to predict the performance of the pilot system will be shown.

  5. The Effects of Lithium Triflate (LiCF{sub 3}SO{sub 3}) on the PMMA-based Solid Polymer Electrolytes

    SciTech Connect

    Chew, K. W.; Chen, S. S.; Pang, W. L.; Tan, C. G.; Osman, Z.

    2010-03-11

    The effects of Lithium triflate salt (LiCF{sub 3}SO{sub 3}), on the poly (methyl methacrylate)(PMMA)-based solid polymer electrolytes plasticized with propylene carbonate (PC) solvated in Tetrahydrofuran (THF) have been studied through a.c impedance spectroscopy and infrared spectroscopy. Lithium triflate was incorporated into the predetermined PMMA/PC system that has the highest value of ionic conductivity. In current investigations, four combination systems: Pure PMMA, (PMMA+PC) systems, (PMMA+LiCF{sub 3}SO{sub 3}) and (PMMA+PC+LiCF{sub 3}SO{sub 3}) systems were prepared using the solution cast method. Solutions were stirred for numerous hours to obtain a homogenous solution before it is poured into the petri dishes under ambient temperature to form the solid electrolyte thin film. The films were then removed from petri discs and transferred into the dessicator for further drying prior to the different tests. From the characterization done through the a.c impedance spectroscopy, the highest room temperature ionic conductivity in the pure PMMA sample, (PMMA+PC) system and (PMMA+LiCF{sub 3}SO{sub 3}) system is 2.83x10{sup -12} Scm{sup -1}, 4.39x10{sup -11} Scm{sup -1} and 3.93x10{sup -6} Scm{sup -1} respectively. The conductivity for (PMMA+PC+LiCF{sub 3}SO{sub 3}) system was obtained with the 30 wt% of lithium triflate, which is 2.48x10{sup -5} Scm{sup -1}. Infrared spectroscopy shows that complexation occurred between the polymer and the plasticizer, and the polymer and plasticizer and salt. The interactions have been studied in the C=O band, C-O-C band and the O-CH{sub 3} band.

  6. Effects of H{sub 2}O, SO{sub 2}, and NO on homogeneous Hg oxidation by Cl{sub 2}

    SciTech Connect

    Hans Agarwal; Harvey G. Stenger; Song Wu; Zhen Fan

    2006-05-15

    Several researchers have determined that water (H{sub 2}O) and sulfur dioxide (SO{sub 2}) in a flue gas stream have an impact on the amount of elemental mercury (Hg{sup 0}) that is homogeneously oxidized by a chlorine-containing species. Generally, it is concluded that H{sub 2}O inhibits Hg oxidation by chlorine (Cl{sub 2}). However, doubt remains as to whether SO{sub 2} promotes or inhibits Hg oxidation. Further, most published results seem to indicate that nitric oxide (NO) does not have a significant impact on Hg oxidation. This paper will present data taken in a laboratory-scale apparatus designed to test these observations. In this work, Cl{sub 2} is intentionally added to a synthetic flue gas stream containing known amounts of elemental mercury. This gas blend is similar to a flue gas obtained by burning Powder River Basin coal in a pulverized coal fired power plant and is subject to a time-temperature profile similar to a power plant. The results obtained show that H{sub 2}O, SO{sub 2}, and NO all have an inhibitory effect on the homogeneous oxidation of Hg by Cl{sub 2}. Further, the presence of H{sub 2}O increases the inhibitory effect of SO{sub 2} and NO. Two new reactions are proposed to explain these results, in which SO{sub 2} and NO react with Cl{sub 2}. The consequences of these reactions are a reduction in the oxidative interactions that take place between Hg and Cl{sub 2}, thus decreasing the amount of Hg oxidation that occurs. 10 refs., 6 figs., 5 tabs.

  7. Automatic electrochemical ambient air monitor for chloride and chlorine

    DOEpatents

    Mueller, Theodore R.

    1976-07-13

    An electrochemical monitoring system has been provided for determining chloride and chlorine in air at levels of from about 10-1000 parts per billion. The chloride is determined by oxidation to chlorine followed by reduction to chloride in a closed system. Chlorine is determined by direct reduction at a platinum electrode in 6 M H.sub.2 SO.sub.4 electrolyte. A fully automated system is utilized to (1) acquire and store a value corresponding to electrolyte-containing impurities, (2) subtract this value from that obtained in the presence of air, (3) generate coulometrically a standard sample of chlorine mixed with air sample, and determine it as chlorine and/or chloride, and (4) calculate, display, and store for permanent record the ratio of the signal obtained from the air sample and that obtained with the standard.

  8. Air Abrasion

    MedlinePlus

    ... delivered directly to your desktop! more... What Is Air Abrasion? Article Chapters What Is Air Abrasion? What Happens? The Pros and Cons Will I Feel Anything? Is Air Abrasion for Everyone? print full article print this ...

  9. Measuring the benefits from air pollution abatement on human health and welfare: a case study of Jacksonville, Florida

    SciTech Connect

    Erfani-Ezati, G.

    1984-01-01

    The purpose of this study was to test benefit measures of air pollution to human health and welfare. Two market approaches, labor market (wage rate) and housing market (property value), were employed to estimate benefits from improvements in air quality. Indices of air pollution used in this study were sulfur dioxide (SO/sub 2/) and total suspended particulate matter (TSP). Using the labor market approach as a measure of benefits from improved air quality, a Mortality Effect Model (MEM) was developed. Then, the model was utilized to quantify the estimates of the pollution mortality relationship for the city of Jacksonville. The resulting pollution related mortality function was then monetized by applying estimates of individual's willingness to pay for mortality reductions. The MEM was estimated using multiple regression analysis. TSP showed no statistically significant association with mortality rates. The significance of the estimated coefficient for the pollution variable SO/sub 2/ supported the contention that some form of air pollution bears a positive and significant relationship to mortality rates. By utilizing a willingness to pay estimate for mortality reductions, it was concluded that individuals in Jacksonville would be willing to pay a minimum of $10 million annually, in order to maintain SO/sub 2/ concentrations at a level of 1% below the average for 1972.

  10. Regeneration process for spent SO/sub 2/-NO/sub x/ sorbents

    SciTech Connect

    Nelson, B.W.; Nelson, S.G.

    1989-05-09

    A regeneration process is described for MgO-vermiculite and MgO-perlite sorbents employed to remove nitrogen and sulfur oxides from a flue gas comprising the following steps: (a) Heating the spent sorbents in air to a temperature in the range of 100/sup 0/ to 350/sup 0/C to drive off substantially all free and chemically attached water; (b) Further heating the spent sorbents in an atmosphere containing a reducing gas selected from the group consisting of carbon monoxide, methane and hydrogen to a temperature in the range of 350/sup 0/ to 450/sup 0/C to drive off sorbed nitrogen oxides; (c) Further heating the spent sorbents in the same atmosphere containing a reducing gas to a temperature in the range of 450/sup 0/ to 700/sup 0/C to drive off approximately 90 percent of the sorbed sulfur in the form of sulfur oxides and elemental sulfur and to destroy substantially all nitrogen oxides present in the exit gases; (d) Cooling the sorbents to a temperature below 200/sup 0/C for reuse.

  11. Implications of a stochastic approach to air-quality regulations

    SciTech Connect

    Witten, A.J.; Kornegay, F.C.; Hunsaker, D.B. Jr.; Long, E.C. Jr.; Sharp, R.D.; Walsh, P.J.; Zeighami, E.A.; Gordon, J.S.; Lin, W.L.

    1982-09-01

    This study explores the viability of a stochastic approach to air quality regulations. The stochastic approach considered here is one which incorporates the variability which exists in sulfur dioxide (SO/sub 2/) emissions from coal-fired power plants. Emission variability arises from a combination of many factors including variability in the composition of as-received coal such as sulfur content, moisture content, ash content, and heating value, as well as variability which is introduced in power plant operations. The stochastic approach as conceived in this study addresses variability by taking the SO/sub 2/ emission rate to be a random variable with specified statistics. Given the statistical description of the emission rate and known meteorological conditions, it is possible to predict the probability of a facility exceeding a specified emission limit or violating an established air quality standard. This study also investigates the implications of accounting for emissions variability by allowing compliance to be interpreted as an allowable probability of occurrence of given events. For example, compliance with an emission limit could be defined as the probability of exceeding a specified emission value, such as 1.2 lbs SO/sub 2//MMBtu, being less than 1%. In contrast, compliance is currently taken to mean that this limit shall never be exceeded, i.e., no exceedance probability is allowed. The focus of this study is on the economic benefits offered to facilities through the greater flexibility of the stochastic approach as compared with possible changes in air quality and health effects which could result.

  12. Cooling of Gas Turbines I - Effects of Addition of Fins to Blade Tips and Rotor, Admission of Cooling Air Through Part of Nozzles, and Change in Thermal Conductivity of Turbine Components

    NASA Technical Reports Server (NTRS)

    Brown, Byron

    1947-01-01

    An analysis was developed for calculating the radial temperature distribution in a gas turbine with only the temperatures of the gas and the cooling air and the surface heat-transfer coefficient known. This analysis was applied to determine the temperatures of a complete wheel of a conventional single-stage impulse exhaust-gas turbine. The temperatures were first calculated for the case of the turbine operating at design conditions of speed, gas flow, etc. and with only the customary cooling arising from exposure of the outer blade flange and one face of the rotor to the air. Calculations were next made for the case of fins applied to the outer blade flange and the rotor. Finally the effects of using part of the nozzles (from 0 to 40 percent) for supplying cooling air and the effects of varying the metal thermal conductivity from 12 to 260 Btu per hour per foot per degree Farenheit on the wheel temperatures were determined. The gas temperatures at the nozzle box used in the calculations ranged from 1600F to 2000F. The results showed that if more than a few hundred degrees of cooling of turbine blades are required other means than indirect cooling with fins on the rotor and outer blade flange would be necessary. The amount of cooling indicated for the type of finning used could produce some improvement in efficiency and a large increase in durability of the wheel. The results also showed that if a large difference is to exist between the effective temperature of the exhaust gas and that of the blade material, as must be the case with present turbine materials and the high exhaust-gas temperatures desired (2000F and above), two alternatives are suggested: (a) If metal with a thermal conductivity comparable with copper is used, then the blade temperature can be reduced by strong cooling at both the blade tip and root. The center of the blade will be less than 2000F hotter than the ends; (b) With low conductivity materials some method of direct cooling other than

  13. Anthropogenic SO{sub 2}/NO{sub x} committee summary of current status--annual inventory

    SciTech Connect

    Benkovitz, C.M.

    1992-06-01

    At the First GEIA Workshop on Global Emissions Inventories, held in Baltimore, MD on December 1--2, 1991, data on anthropogenic emissions of sulfur and nitrogen developed by Dignon (1992) were selected to form the basis for the GEIA SO{sub 2} and NO{sub x} annual inventories. The Dignon data include emissions from fuel combustion only and currently extend to 1980. The methodology used was detailed in Dignon and Hameed (1985) and consists of statistical regression models based on available emissions data from the U.S and some other member countries of the Organization of Economic Cooperation and Development (OECD), which includes Australia, Canada, Japan and western European countries. Control regulations are incorporated via the use of different statistical parameter The grid definition from these inventories was also adopted for the GEIA grid: origin at 180{degree}W, 90{degree}S, 1{degree} {times} 1{degree} resolution (i.e., 360 cells in the longitude direction, 180 cells in the latitude direction). To upgrade the basic GEIA inventories, data for the different geographic regions being solicited from researchers located within these areas. This paper contains the upgrades which have been accomplished to date.

  14. Simultaneous SO{sub 2}/NO{sub x} removal testing and toxics characterization. Milestone report, phase 1

    SciTech Connect

    Whitcomb, J.; Tseng, Shiaw; Lani, B.W.

    1996-09-01

    This report describes the work completed in the first phase of the Simultaneous SO{sub 2}/NO{sub x} Removal Testing and Toxics Characterization test program. Tasks covered in this report as specified in the Statement of Work included: Task 1.2.0 Equipment Modification and Reagents Procurement; Task 1.3.0 Testing at the 5 kW Scale; Task 1.3.1 Temperature Enhanced Fe(III)EDTA Reduction; Task 1.3.2 Electrolytic Cell Fe(III) EDTA Reduction; Task 1.3.3 Chemical Regeneration Agents Testing; Task 1.3.4 Combination of Strategies; Task 1.4.0 Data Analysis and Phase I Report. Proposed in Task 1.3.4 are combinations of regeneration methods (based on data generated in Tasks 1.3.1 to 1.3.3) that gave the best results at the lowest possible cost. The Test Plan approval (Task 1.1.0) was previously submitted under separate cover.

  15. Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system

    SciTech Connect

    Renk, J.B. III

    1995-06-01

    This environmental assessment (EA) was prepared to evaluate the potential impacts of a proposed demonstration project to be cost-shared by DOE and NOXSO Corporation under the terms of Clean Coal Technology (CCT) Demonstration Program. The project would demonstrate the NOXSO flue gas treatment technology, which is designed to reduce sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) emissions from existing coal-fired electric generating units. Its objective is to introduce advanced, efficient, reliable, and environmentally improved coal utilization technologies to the U.S. energy marketplace, in order to reduce or eliminate economic and environmental barriers to the continued use of coal as an energy source. This EA represents the third level of DOE`s NEPA strategy: the preparation and public distribution of NEPA documents for each project selected for financial assistance under the PON. It contains a site-specific environmental impact analysis of the proposed federal action, and will result in either a Finding of No Significant Impact, or a determination that significant impacts may occur, in which case an Environmental Impact Statement must be prepared. The sources of information for this EA include the technical proposal for the project submitted by NOXSO in response to the CCT Round III PON; discussions with NOXSO and their consultants; discussions with federal, state and local agencies; the April 1995 NOXSO Environmental Information Volume provided to DOE for the project; and visits to the proposed project sites.

  16. Hydrothermal Formation Of Hemi-hydrate Calcium Sulfate Whiskers In The Presence Of Additives

    SciTech Connect

    Luo, K. B.; Li, C. M.; Li, H. P.; Ning, P.; Xiang, L.

    2010-11-24

    The influence of addictives on the hydrothermal formation of hemi-hydrate calcium sulfate (CaSO{sub 4{center_dot}}0.5H{sub 2}O) whiskers were discussed in this paper, using CaCl{sub 2} and Na{sub 2}SO{sub 4} as the reactants. The presence of NaCl, CaCl{sub 2} or Na{sub 2}SO{sub 4} increased the concentrations of Ca{sup 2+} and SO{sub 4}{sup 2-}, leading to the formation of CaSO{sub 4{center_dot}}0.5H{sub 2}O whiskers with aspect ratio lower than 50. The one dimensional growth of CaSO{sub 4{center_dot}}0.5H{sub 2}O whiskers was enhanced in water with no additives owing to the low super-saturation, leading to the formation of uniform whiskers with a length of 200-2000 {mu}m and an aspect ratio higher than 100.

  17. Effect of swift heavy ion irradiation on conductivity and relaxation time in PVA-PEO-EC-LiCF{sub 3}SO{sub 3} blends

    SciTech Connect

    Joge, Prajakta; Kanchan, D. K.; Sharma, Poonam; Jayswal, Manish; Gondaliya, Nirali; Awasthi, D. K.

    2013-02-05

    In the present work, the PVA-PEO-EC-LiCF{sub 3}SO{sub 3} blend specimens complexed with 3 wt%LiCF{sub 3}SO{sub 3} salt have been irradiated, using swift heavy O{sup 7+} ion irradiation of 80MeV. These blend films have been irradiated with four different fluences ranging from 1 Multiplication-Sign 10{sup 11} to 3 Multiplication-Sign 10{sup 12} ions/cm{sup 2}. Effect of radiations on conductivity, power law exponent and relaxation time of the films has been investigated in the present study. Conductivity is observed to enhance on increasing the fluence upto 3 Multiplication-Sign 10{sup 11} ions/cm{sup 2} and drops with further increment of fluence. However, all the irradiated blend specimens show higher conductivity as compared to pristine blend specimen.

  18. Electron transfer from indoles, phenol, and sulfite (SO/sub 3//sup 2 -/) to chlorine dioxide (ClO/sub 2//sup. /)

    SciTech Connect

    Merenyi, G.; Lind, J.; Shen, X.

    1988-01-14

    With the ClO/sub 2//ClO/sub 2//sup -/ couple as reference the one-electron-reduction potentials have been determined for four methylated indolyl radical cations. Their E/sup 0/ values are 1.23 V (N-Me), 1.10 V (2-Me), 1.07 V (3-Me), and 0.93 V (2,3-diMe). E/sup 0/ values were also measured for the following: tryptophylH/sup .+//trypH 1.24 V, SO/sub 3//sup .-//SO/sub 3//sup 2 -/ 0.76 V, and phenoxy/sup .//phenolate 0.80 V. The redox potentials were obtained from purely kinetic data (for tryptophan and 2-,3-, and N-methylindole) or from combined kinetic and thermodynamic measurements.

  19. Conductivity enhancement in PVA−PEO−EC−LiCF−{sub 3}SO{sub 3} blends upon swift heavy O{sup 7+} ion irradiation

    SciTech Connect

    Joge, Prajakta Kanchan, D. K. Sharma, Poonam Jayswal, Manish; Awasthi, D. K.

    2014-04-24

    In the present study, the PVA−PEO−EC−LiCF−{sub 3}SO{sub 3} blend system was prepared using solution cast technique. The system was prepared by taking 5 different concentrations LiCF{sub 3}SO{sub 3} in the range of 3wt% to 11 wt%, at a fixed proportion of the rest of the constituents. These blend films had been exposed to O{sup 7+} radiations of 80 MeV at a current of 1pnA at a fluence of 1×10{sup 12} ions/cm{sup 2}. The conductivity variation of the specimens is investigated using impedance spectroscopy wherein; the conductivity enhances drastically upon irradiation at all the concentrations of salt. The thermal characteristics of the blend films are being studied using Differential Scanning Calorimetry.

  20. Dry desulfurization of simulated flue gas in a fluidized-bed reactor for a broad range of SO{sub 2} concentration and temperature: A comparison of models

    SciTech Connect

    Suyadal, Y.; Oguz, H.

    1999-08-01

    In this work, dry desulfurization of simulated flue gas was investigated in a batchwise operated laboratory-scale stainless steel fluidized-bed reactor (46 x 500 mm{sup 2}) by using calcium-containing local Turkish limestone (Karaagach/MUS) which was calcined at 900 C with 5% H{sub 2}O vapor. The sulfation reaction was carried out in a broad range of temperature (200 {le} T({degree}C) {le} 900) and SO{sub 2} feedstock concentration (1000 {le} C(ppm SO{sub 2}) {le} 6000). The experimental sulfation conversion-time data were tested according to unreacted shrinking core model (SCM), changing the grain size model (GM) and random pore model (RPM). It was found that the random pore model with control of product layer (CaSO{sub 3}/CaSO{sub 4}) diffusion described the experimental data best.

  1. Kentucky Department for Natural Resources and Environmental Protection permit application for air contaminant source: SRC-I demonstration plant, Newman, Kentucky. Supplement I. [Additional information on 38 items requested by KY/DNREP

    SciTech Connect

    Pearson, Jr., John F.

    1981-02-13

    In response to a letter from KY/DNREP, January 19, 1981, ICRC and DOE have prepared the enclosed supplement to the Kentucky Department for Natural Resources and Environmental Protection Permit Application for Air Contaminant Source for the SRC-I Demonstration Plant. Each of the 38 comments contained in the letter has been addressed in accordance with the discussions held in Frankfort on January 28, 1981, among representatives of KY/DNREP, EPA Region IV, US DOE, and ICRC. The questions raised involve requests for detailed information on the performance and reliability of proprietary equipment, back-up methods, monitoring plans for various pollutants, composition of wastes to flares, emissions estimates from particular operations, origin of baseline information, mathematical models, storage tanks, dusts, etc. (LTN)

  2. Response of sulfate concentration and isotope composition in Icelandic rivers to the decline in global atmospheric SO{sub 2} emissions into the North Atlantic region

    SciTech Connect

    Sigurdur Reynir Gislason; Peter Torssander

    2006-02-01

    This study presents the changes in dissolved sulfate concentration and isotope composition of Icelandic river waters between the peak of SO{sub 2} emissions in the United States and Europe and the present. Chloride concentration in Icelandic rivers has not changed much since 1972. The overall average change from 1972-1973 to 1996-2004 was -3%, indicating insignificant sea-salt contribution changes. More than 99% of the river-dissolved sulfur was in the form of sulfate. There are three main sources for dissolved sulfate in the rivers: rocks, sea-salts, and anthropogenic. Total dissolved sulfate, {sub td}SO{sub 4}{sup 2-}, and non-sea-salt sulfate, {sub nss}SO{sub 4}{sup 2-}, decreased in all of the rivers from the early 1970s to 1996-2004. The percentage decrease varies from 13% to 65%. The decrease is smallest in rivers were there is considerable rock-derived dissolved SO{sub 4}{sup 2-}. The overall average decrease was 39% for {sub td}SO{sub 4}{sup 2-} and 46% for {sub nss}SO{sub 4}{sup 2-}. The anthropogenic sulfate fraction has declined making most of the river waters {delta}{sup 34}S values of sulfate higher through time. The overall decline in river sulfate and increase in {delta}{sup 34}S, while SO{sub 2} emissions from Iceland has been increasing, demonstrates the response of river chemistry in the remote North Atlantic to the decline in man-made emissions of SO{sub 2} in North America and Europe. 43 refs., 8 figs., 1 tab.

  3. SILVA: a model for forecasting the effects of SO/sub 2/ pollution on growth and succession in a western coniferous forest

    SciTech Connect

    Kercher, J.R.; Axelrod, M.C.

    1981-02-26

    A forest succession simulator, SILVA, has been developed for the mixed conifer forest type of the Sierra Nevada, California (seven major species), to simulate the effects of SO/sub 2/ on forest dynamics. SILVA was developed by extensively modifying a northeastern US simulator. The model simulates growth and includes the development in time of tree diameter, tree height, leaf area index, and available light for each tree. Recruitment and mortality are modeled stochastically. Modifications include the introduction of fire ecology and the use of temporal seed-crop patterns and seedling survival factors unique to Sierra Nevada forests. Probability of mortality is determined by height of crown scorch (which is a function of fire intensity), dbh, and bark thickness. Pollutant impacts are modeled as an effect on tree growth. Dose-response functions relating change in tree growth to increases in pollutant loads were developed using published data. The model simulates community dynamical and structural response to many factors quite well. For 500-year simulations from clearcut, the ratios of the time-averaged basal area fraction of Pinus ponderosa to Abies concolor were 5.2:1 and 1:16 for elevations of 1524 m and 1829 m, respectively. At 1524 m, the ratio of P. ponderosa to A. concolor decreased 59% with the introduction of fire suppression. To investigate effects of low-level chronic SO/sub 2/ fumigation in sample runs, the pollutant level is set to cause these annual reductions in growth: P. ponderosa, 10%; Pseudotsuga menziesii, 18%; and SO/sub 2/-tolerant species such as A. concolor, 1 to 2%. Time-averaged P. ponderosa basal area fraction decreased 28% and A. concolor (SO/sub 2/ tolerant) increased by 260% at 1524 m elevation. Three scenarios of pollutant time histories are investigated: rising levels, constant levels, and rising and falling levels. We also calculate the sensitivities of the model parameters to determine relative importance for model behavior.

  4. Comparative study of the reactions of metal oxides with H{sub 2}S and SO{sub 2}. Technical progress report, July--September 1991

    SciTech Connect

    Sotirchos, S.V.

    1991-10-01

    The primary objective of this project is the investigation of the effects of pore structure on the capacity of porous metal oxides for removal of gaseous pollutants from flue gases of power plants (SO{sub 2}) and hot coal gas (primarily H{sub 2}S). Specifically, we intend to appropriately exploit the differences of the sulfidation and sulfation reactions (for instance, different molar volumes of solid products) to elucidate the dependence of the sorptive capacity of a porous sorbent on its physical microstructure. The following tasks have been identified in the proposed project: (1) Literature survey and identification of solids to be used in experimental studies. (2) Experimental study of the reaction of the chosen solids with SO{sub 2} and/or H{sub 2}S. (3) Experimental study of the evolution of the structure of the solids during reaction with SO{sub 2} and/or H{sub 2}S using pore structure analysis and effective diffusivity measurements. (4) Model testing and validation using the obtained experimental data.

  5. A study of the chemical composition of the passive film on a Ti-Mo alloy in HCl and H{sub 2}SO{sub 4}

    SciTech Connect

    Wang, G.; Wang, H.; Liu, X.

    1997-04-01

    The composition of the passive film on Ti-15Mo alloy, formed in 1 mol/L and 4 mol/L HCl and 2 mol/L H{sub 2}SO{sub 4} solutions at 70 C (160 F) under anodic polarization is investigated by XPS and electrochemical techniques. Anodic polarization potential is found to have an obvious influence on the content of Mo in the film. At lower anodic polarization potentials, the surface of the passive film is enriched in Mo. However, at higher anodic polarization potentials, the surface is diluted in Mo. The anions of the electrolytes influence the composition of the passive film. In HCl solution, chloride ions are incorporated with the passive film during its formation. The passive film consists of a compound containing chloride and oxide ions. While in H{sub 2}SO{sub 4} solution, the passive film only consists of titanium-molybdenum oxide. Sulfide ions and other sulfur are not incorporated. Ti-Mo alloys have a better passivity than pure Ti in HCl and H{sub 2}SO{sub 4} solutions. This passivity is related to the enrichment of Mo in the surface of the passive film.

  6. Potential impact of combined NO[sub x] and SO[sub x] emissions from future high speed civil transport aircraft on stratospheric aerosols and ozone

    SciTech Connect

    Bekki, S.; Pyle, J.A.

    1993-02-01

    A two-dimensional sulfate aerosol model is used to assess the impact of combined NO[sub x] and SO[sub x] emissions from future High Speed Civil Transports on stratospheric aerosols and ozone. The model predicts that SO[sub x] emitted by this fleet of supersonics may double the aerosol surface area and the number of optically active particles below 20 km in the northern lower stratosphere. When the heterogeneous conversion of N[sub 2]O[sub 5] to HNO[sub 3] on sulfate aerosols is taken into account, the predicted ozone changes due to future HSCTs emissions are smaller than those calculated when SO[sub x] and the subsequent increase in aerosol loading are neglected. It is worth noting that the doubling of the aerosol surface area may lead not only to a reduction in predicted ozone sensitivity to NO[sub x], but also to an enhancement in ozone sensitivity to chlorine in the lower stratosphere. 23 refs., 3 figs.

  7. Development and testing of a PEM SO>2-depolarized electrolyzer and an operating method that prevents sulfur accumulation

    SciTech Connect

    Steimke, John L.; Steeper, Timothy J.; Colon-Mercado, Hector R.; Gorensek, Maximilian B.

    2015-09-02

    The hybrid sulfur (HyS) cycle is being developed as a technology to generate hydrogen by splitting water, using heat and electrical power from a nuclear or solar power plant. A key component is the SO>2-depolarized electrolysis (SDE) cell, which reacts SO>2 and water to form hydrogen and sulfuric acid. SDE could also be used in once-through operation to consume SO>2 and generate hydrogen and sulfuric acid for sale. A proton exchange membrane (PEM) SDE cell based on a PEM fuel cell design was fabricated and tested. Measured cell potential as a function of anolyte pressure and flow rate, sulfuric acid concentration, and cell temperature are presented for this cell. Sulfur accumulation was observed inside the cell, which could have been a serious impediment to further development. A method to prevent sulfur formation was subsequently developed. As a result, this was made possible by a testing facility that allowed unattended operation for extended periods.

  8. Advanced byproduct recovery: Direct catalytic reduction of SO{sub 2} to elemental sulfur. First quarterly technical progress report, [October--December 1995

    SciTech Connect

    Benedek, K.; Flytzani-Stephanopoulos, M.

    1996-02-01

    The team of Arthur D. Little, Tufts University and Engelhard Corporation will be conducting Phase I of a four and a half year, two-phase effort to develop and scale-up an advanced byproduct recovery technology that is a direct, single-stage, catalytic process for converting sulfur dioxide to elemental sulfur. this catalytic process reduces SO{sub 2} over a fluorite-type oxide (such as ceria or zirconia). The catalytic activity can be significantly promoted by active transition metals, such as copper. More than 95% elemental sulfur yield, corresponding to almost complete sulfur dioxide conversion, was obtained over a Cu-Ce-O oxide catalyst as part of an ongoing DOE-sponsored University Coal Research Program. This type of mixed metal oxide catalyst has stable activity, high selectivity for sulfur production, and is resistant to water and carbon dioxide poisoning. Tests with CO and CH{sub 4} reducing gases indicates that the catalyst has the potential for flexibility with regard to the composition of the reducing gas, making it attractive for utility use. the performance of the catalyst is consistently good over a range of SO{sub 2} inlet concentration (0.1 to 10%) indicating its flexibility in treating SO{sub 2} tail gases as well as high concentration streams.

  9. 77 FR 68738 - Procurement List; Additions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-16

    ...), Air Resources Laboratory, 456 S. Illinois Avenue, Oak Ridge, TN. NPA: Goodwill Industries--Knoxville... . SUPPLEMENTARY INFORMATION: Additions On 9/14/2012 (77 FR 56813-56814) and 9/21/2012 (77 FR 58528-58529),...

  10. Air resources

    SciTech Connect

    1995-10-01

    This section describes the ambient (surrounding) air quality of the TVA region, discusses TVA emission contributions to ambient air quality, and identifies air quality impacts to human health and welfare. Volume 2 Technical Document 2, Environmental Consequences, describes how changes in TVA emissions could affect regional air quality, human health, environmental resources, and materials. The primary region of the affected environment is broadly defined as the state of Tennessee, as well as southern Kentucky, western Virginia, southern West Virginia, western North Carolina, and northern Georgia, Alabama, and Mississippi. This area represents the watershed of the Tennessee River and the 201 counties of the greater TVA service area. Emissions from outside the Tennessee Valley region contribute to air quality in the Valley. Also, TVA emissions are transported outside the Valley and have some impact on air quality beyond the primary study area. Although the study area experiences a number of air quality problems, overall air quality is good.

  11. Metal-air battery assessment

    SciTech Connect

    Sen, R.K.; Van Voorhees, S.L.; Ferrel, T.

    1988-05-01

    The objective of this report is to evaluate the present technical status of the zinc-air, aluminum/air and iron/air batteries and assess their potential for use in an electric vehicle. In addition, this report will outline proposed research and development priorities for the successful development of metal-air batteries for electric vehicle application. 39 refs., 25 figs., 11 tabs.

  12. Iron-Air Rechargeable Battery

    NASA Technical Reports Server (NTRS)

    Narayan, Sri R. (Inventor); Prakash, G.K. Surya (Inventor); Kindler, Andrew (Inventor)

    2014-01-01

    Embodiments include an iron-air rechargeable battery having a composite electrode including an iron electrode and a hydrogen electrode integrated therewith. An air electrode is spaced from the iron electrode and an electrolyte is provided in contact with the air electrode and the iron electrodes. Various additives and catalysts are disclosed with respect to the iron electrode, air electrode, and electrolyte for increasing battery efficiency and cycle life.

  13. Applications Using AIRS Data

    NASA Astrophysics Data System (ADS)

    Ray, S. E.; Pagano, T. S.; Fetzer, E. J.; Lambrigtsen, B.; Olsen, E. T.; Teixeira, J.; Licata, S. J.; Hall, J. R.; Thompson, C. K.

    2015-12-01

    The Atmospheric Infrared Sounder (AIRS) on NASA's Aqua spacecraft has been returning daily global observations of Earth's atmospheric constituents and properties since 2002. With a 12-year data record and daily, global observations in near real-time, AIRS data can play a role in applications that fall under many of the NASA Applied Sciences focus areas. For vector-borne disease, research is underway using AIRS near surface retrievals to assess outbreak risk, mosquito incubation periods and epidemic potential for dengue fever, malaria, and West Nile virus. For drought applications, AIRS temperature and humidity data are being used in the development of new drought indicators and improvement in the understanding of drought development. For volcanic hazards, new algorithms using AIRS data are in development to improve the reporting of sulfur dioxide concentration, the burden and height of volcanic ash and dust, all of which pose a safety threat to aircraft. In addition, anomaly maps of many of AIRS standard products are being produced to help highlight "hot spots" and illustrate trends. To distribute it's applications imagery, AIRS is leveraging existing NASA data frameworks and organizations to facilitate archiving, distribution and participation in the BEDI. This poster will communicate the status of the applications effort for the AIRS Project and provide examples of new maps designed to best communicate the AIRS data.

  14. Storage corrosion of materials and equipment: Temperature-humidity and aerochemical regimes indoors and in the open air

    SciTech Connect

    Strekalov, P.V.

    1994-07-01

    The following storage factors are considered: (1) the temperature-humidity complex (THC) in the open air at representative sites with cold, moderate, and subtropical humid climate; (2) the temperature and humidity differences between the open air and an atmospheric of semiclosed spaces; (3) the THC inside storage-spaces in a humid tropical climate; (4) the concentration of SO{sub 2} and Cl{sup -} in the open air and in different storage-spaces; (5) the categories of corrosivity of the atmosphere and methods for its evaluation indoors and outdoors.

  15. Air Pollution.

    ERIC Educational Resources Information Center

    Gilpin, Alan

    A summary of one of our most pressing environmental problems, air pollution, is offered in this book by the Director of Air Pollution Control for the Queensland (Australia) State Government. Discussion of the subject is not restricted to Queensland or Australian problems and policies, however, but includes analysis of air pollution the world over.…

  16. Preconception and early pregnancy air pollution exposures and risk of gestational diabetes mellitus

    SciTech Connect

    Robledo, Candace A.; Mendola, Pauline; Yeung, Edwina; Männistö, Tuija; Sundaram, Rajeshwari; Liu, Danping; Ying, Qi; Sherman, Seth; Grantz, Katherine L.

    2015-02-15

    Background: Air pollution has been linked to gestational diabetes mellitus (GDM) but no studies have evaluated impact of preconception and early pregnancy air pollution exposures on GDM risk. Methods: Electronic medical records provided data on 219,952 singleton deliveries to mothers with (n=11,334) and without GDM (n=208,618). Average maternal exposures to particulate matter (PM) ≤ 2.5 μm (PM{sub 2.5}) and PM{sub 2.5} constituents, PM ≤ 10 μm (PM{sub 10}), nitrogen oxides (NO{sub x}), carbon monoxide, sulfur dioxide (SO{sub 2}) and ozone (O{sub 3}) were estimated for the 3-month preconception window, first trimester, and gestational weeks 1–24 based on modified Community Multiscale Air Quality models for delivery hospital referral regions. Binary regression models with robust standard errors estimated relative risks (RR) for GDM per interquartile range (IQR) increase in pollutant concentrations adjusted for study site, maternal age and race/ethnicity. Results: Preconception maternal exposure to NO{sub X} (RR=1.09, 95% CI: 1.04, 1.13) and SO{sub 2} (RR=1.05, 1.01, 1.09) were associated with increased risk of subsequent GDM and risk estimates remained elevated for first trimester exposure. Preconception O{sub 3} was associated with lower risk of subsequent GDM (RR=0.93, 0.90, 0.96) but risks increased later in pregnancy. Conclusion: Maternal exposures to NO{sub x} and SO{sub 2} preconception and during the first few weeks of pregnancy were associated with increased GDM risk. O{sub 3} appeared to increase GDM risk in association with mid-pregnancy exposure but not in earlier time windows. These common exposures merit further investigation. - Highlights: • Air pollution may be related to gestational diabetes (GDM). • No prior studies have examined preconception exposure. • Maternal exposure to NO{sub x} and SO{sub 2} before conception increased subsequent GDM risk. • NO{sub x} and SO{sub 2} exposure in the first seven weeks of pregnancy also increased

  17. Air pollution effects on the structure of Citrus aurantium leaves

    SciTech Connect

    Psaras, G.K.; Christodoulakis, N.S.

    1987-09-01

    Individual air pollutants cause acute and chronic plant injury, act on stomata and affect carbon dioxide exchange as well as plant growth and development. Inhibition of photosynthesis by several air pollutants has been reported repeatedly. Besides, structural modifications of cell organelles have been reported after fumigation by SO/sub 2/. Although chlorosis and subsequent necrosis are common phenomena caused by artificial treatment with pollutants, fine structural leaf characteristics of plants exposed to long-term air pollution in natural conditions are little explored. Light microscope examination of air pollution affected leaves of plants common in natural ecosystems of Athens' metropolitan area revealed chlorosis phenomena. Electron microscope examination of the leaves of a common subshrub of greek phryganic formations grown in a heavily air polluted natural ecosystem of Athens metropolitan area revealed pronounced ultrastructural anomalies of chloroplasts, mitochondria and microbodies of the mesophyll cells. This organelle destruction of the photosynthesizing tissue as well as the minimization of the ecosystem primary productivity are attributed to the compound action of several toxic air pollutants of the photochemical smog of Athens. This work describes the long-term air pollution effects on the structural features of the leaves of Citrus aurantium, a decorative species planted throughout the heavily air polluted city of Athens.

  18. Correlated model for indoor and outdoor air pollutants

    SciTech Connect

    Chen, L.; Lee, J.S.; Cheng, K.S.

    1998-12-31

    This study tries to correlate outdoor concentration of air pollutants with indoor data statistically and physically by means of on-site measurement. The authors measured concentrations of THC, NMHC, NO{sub x}, SO{sub 2} and O{sub 3} at two residential sites where were closed to a fossil industry area. An air sampling system was designed to alternately sample air from different locations, therefore they can obtain semi-simultaneously indoor and outdoor concentration of air pollutants. Four measurements were taken during a year period. The measured data were analyzed by means of statistical regression and were used to calibrate indoor decay constants in a mass balance physical model. The results of statistical regression show that indoor concentration of air pollutant is highly correlated with outdoor concentration and indoor concentration at one hour earlier rather than outdoor climate parameters such as wind speed, temperature and humidity. The results explained that outdoor concentration actually included factors of outdoor climate parameters implicitly. In physical model, they calibrated the indoor concentration decay constants in an indoor/outdoor mass conservation equation at various air exchange rates under different seasons and day/night conditions. The established statistical and physical models can be used to estimate indoor air quality from monitored or calculated outdoor data. With the proposed correlation models it becomes convenient to perform the overall indoor and outdoor air pollutants exposure and risk assessment.

  19. An Electron Microscopy Investigation of the Transient Stage Oxidation Products in an Fe-22Cr Alloy with Ce and La Additions Exposed to Dry Air at 1073 K (800 °C)

    SciTech Connect

    Jingxi Zhu; Laura Fernandez-Diaz; Gordon Holcomb; Paul Jablonski; Christopher Cowen; David Lauglin; and Sridhar Seetharaman

    2010-10-01

    In this study, the effects of Ce (270 ppm) and La (120 ppm) mischmetal additions on the transient oxidation of an Fe-22Cr alloy were investigated. The oxidation process was imaged in situ using a confocal scanning laser microscope. The oxidation microstructures were studied by scanning electron microscopy, energy dispersive X-ray analysis, and transmission electron microscopy with the help of focused ion beam in situ lift-out specimen preparation. The Ce and La, referred to as reactive elements, were found in nonmetallic inclusion particles in the forms of oxides, sulfides, and phosphates. An affected zone formed around rare earth (RE)-containing inclusion particles at the alloy free surface during the transient oxidation. This zone consisted of an internal Cr-oxide formed beneath the particle as well as a thinner external oxide scale on the surface compared with the surroundings. The relation of this microstructure to oxidation kinetics is discussed. With time, the RE elements diffused into the scale from the RE particles on the alloy surface during the high-temperature exposure. A diffusion mechanism is presented to describe these observations.

  20. Kinetics of the reaction of hydrated lime with SO{sub 2} at low temperatures: effects of the presence of CO{sub 2}, O{sub 2}, and NOx

    SciTech Connect

    Liu, C.F.; Shih, S.M.

    2008-12-15

    The effects of the presence Of CO{sub 2}, O{sub 2}, and NOx in the flue gas on the kinetics of the sulfation of hydrated lime at low temperatures were studied using a differential fixed-bed reactor. When O{sub 2} and NOx were not present together the reaction kinetics was about the same as that under gas mixtures containing SO{sub 2}, H{sub 2}O, and N2 only. When both O{sub 2} and NOx were present, sulfation of hydrated lime was greatly enhanced, forming a large amount of calcium sulfate in addition to calcium sulfite. Sulfation of hydrated lime was well described by the surface coverage model, despite the gas-phase conditions being different. Relative humidity is the major factor affecting the reaction, and its effect was more marked when both O{sub 2} and NOx were present. The kinetic model equations obtained in this work can be used to describe the sulfation of hydrated lime in the low-temperature dry and semidry flue gas desulfurization processes with or without an upstream NOx removal unit.

  1. Tests of stability on waste produced in pilot plant testing using ferrous{center_dot}EDTA and magnesium-enhanced lime for combined SO{sub 2}/NO{sub x} removal

    SciTech Connect

    Mendelsohn, M.H.; Livengood, C.D.

    1994-03-01

    A pilot-plant-scale study of combined sulfur dioxide/nitrogen oxides (SO{sub 2}/NO{sub x}) removal has been performed by the Dravo Lime Company at the Cincinnati Gas and Electric Company`s Miami Fort Station in North Bend, Ohio. This study used Dravo`s patented Thiosorbic{reg_sign} lime process, utilizing a magnesium-enhanced lime, along with Argonne National Laboratory`s (ANL`s) patented ARGONOX metal-chelate additive, ferrous{center_dot}ethylenediaminetetraacetic acid (Fe{center_dot}EDTA). For approximately nine months, scrubbing tests were carried out, and waste samples were collected. Waste testing at ANL involved two types of long-term chemical stability experiments. In one experiment, the gas-phase composition above several different samples was studied by mass spectrometry over a period of about 22 months. Significant changes were noted for oxygen (O{sub 2}), carbon dioxide (CO{sub 2}), and hydrogen sulfide (H{sub 2}S) gases. The other experiment involved solid-phase leaching using the Toxicity Characteristic Leaching Procedure (TCLP). Samples were stored for up to 14 months before leaching. Then each leachate was tested for total Kjeldahl nitrogen and for some nitrogen-containing species. Total leachable nitrogen was found to stabilize after about the first seven months of storage.

  2. Hyperspectral air-to-air seeker

    NASA Astrophysics Data System (ADS)

    Gat, Nahum; Barhen, Jacob; Gulati, Sandeep; Steiner, Todd D.

    1994-07-01

    Synthetic hyperspectral signatures representing an airborne target engine radiation, a decoy flare, and the engine plume radiation are used to demonstrate computational techniques for the discrimination between such objects. Excellent discrimination is achieved for a `single look' at SNR of -10 dB. Since the atmospheric transmittance perturbs the signature of all objects in an identical fashion, the transmittance is equivalent to a modulation of the target radiance (in the spectral domain). The proper spectral signal decomposition may, therefore, recover the original unperturbed signature accurately enough to allow discrimination. The algorithms described here, and in two accompanying papers, have been tested over the spectral range that includes the VNIR and MWIR and are most appropriate for an intelligent, autonomous, air-to-air or surface-to-air guided munitions. With additional enhancements, the techniques apply to ground targets and other dual-use applications.

  3. Ancillary benefits of reduced air pollution in the US from moderate greenhouse gas mitigation policies in the electricity sector.

    SciTech Connect

    Burtraw, D.; Krupnick, A.; Palmer, K.; Paul, A.; Toman, M.; Bloyd, C.; Decision and Information Sciences; Resources for the Future

    2003-05-01

    Actions to slow atmospheric accumulation of greenhouse gases also would reduce conventional air pollutants yielding 'ancillary' benefits that tend to accrue locally and in the near-term. Using a detailed electricity model linked to an integrated assessment framework to value changes in human health, we find a tax of $25 per metric ton of carbon emissions would yield NO{sub x}-related health benefits of about $8 per metric ton of carbon reduced in the year 2010 (1997 dollars). Additional savings of $4-$7 accrue from reduced investment in NO{sub x} and SO{sub 2} abatement in order to comply with emission caps. Total ancillary benefits of a $25 carbon tax are $12-$14, which appear to justify the costs of a $25 tax, although marginal benefits are less than marginal costs. At a tax of $75, greater total benefits are achieved but the value per ton of carbon reductions remains roughly constant at about $12.

  4. Kemira selects outokumpu H/sub 2/SO/sub 4/ plant for Harjavalta, Finland with acid distributor system featuring LEWMET alloy flow components

    SciTech Connect

    Stuart, W.M.; Heinemann, H.C.; Pimia, E.

    1986-01-01

    With a population of 5 million people, Finland ranks as one of Europe's leading fertilizer producers. Thus, it is not surprising that per capita production of sulphuric acid, used in the manufacture of phosphate fertilizer, is among the highest in the world. Finland's leading fertilizer and sulphuric acid producer is Kemira Oy. When a new acid plant was under consideration for their complex at Harjavalta, the decision was made to use the best available technology. Replacing a 25-year old facility, the new plant was to operate on copper smelter SO/sub 2/ gas and have a capacity of 330,000 metric tons of sulphuric acid per year.

  5. Mode of action of air pollutants in injuring horticultural plants

    SciTech Connect

    Tibbitts, T.W.; Kobriger, J.M.

    1983-10-01

    An attempt has been made to condense the great volume of literature for many different air pollutants and from many different plant systems. Only those responses that have been reported for several species are emphasized and the discussion is limited to responses obtained with intact plants. The general outline provides a focus; uptake becomes the crucial aspect of whether or not plants are injured by air pollutants. Pollutants must get into the plant to cause injury and the primary portal of entry is through the open stomata. Once into the plant, pollutants alter biochemical reactions, resulting in cell injury and causing economic losses for horticulturists. The authors have developed this outline for the pollutants sulfur dioxide (SO/sub 2/), hydrogen fluoride (HF), ozone (O/sub 3/), nitrogen dioxide (NO/sub 2/), and peroxyacetyl nitrate (PAN), which are the most common and and most damaging gaseous pollutants in the ambient environment.

  6. Air Pollution.

    ERIC Educational Resources Information Center

    Fox, Donald L.

    1989-01-01

    Materials related to air pollution are reviewed for the period January 1987, to October 1988. The topics are pollution monitoring, air pollution, and environmental chemistry. The organization consists of two major analytical divisions: (1) gaseous methods; and (2) aerosol and particulate methods. (MVL)

  7. Air Pollution.

    EPA Science Inventory

    Air quality is affected by many types of pollutants that are emitted from various sources, including stationary and mobile. These sources release both criteria and hazardous air pollutants, which cause health effects, ecological harm, and material damage. They are generally categ...

  8. Air travel and pneumothorax.

    PubMed

    Hu, Xiaowen; Cowl, Clayton T; Baqir, Misbah; Ryu, Jay H

    2014-04-01

    The number of medical emergencies onboard aircraft is increasing as commercial air traffic increases and the general population ages, becomes more mobile, and includes individuals with serious medical conditions. Travelers with respiratory diseases are at particular risk for in-flight events because exposure to lower atmospheric pressure in a pressurized cabin at cruising altitude may result in not only hypoxemia but also pneumothorax due to gas expansion within enclosed pulmonary parenchymal spaces based on Boyle's law. Risks of pneumothorax during air travel pertain particularly to those patients with cystic lung diseases, recent pneumothorax or thoracic surgery, and chronic pneumothorax. Currently available guidelines are admittedly based on sparse data and include recommendations to delay air travel for 1 to 3 weeks after thoracic surgery or resolution of the pneumothorax. One of these guidelines declares existing pneumothorax to be an absolute contraindication to air travel although there are reports of uneventful air travel for those with chronic stable pneumothorax. In this article, we review the available data regarding pneumothorax and air travel that consist mostly of case reports and retrospective surveys. There is clearly a need for additional data that will inform decisions regarding air travel for patients at risk for pneumothorax, including those with recent thoracic surgery and transthoracic needle biopsy. PMID:24687705

  9. Air bag restraint device

    DOEpatents

    Marts, D.J.; Richardson, J.G.

    1995-10-17

    A rear-seat air bag restraint device is disclosed that prevents an individual, or individuals, from continuing violent actions while being transported in a patrol vehicle`s rear seat without requiring immediate physical contact by the law enforcement officer. The air bag is activated by a control switch in the front seat and inflates to independently restrict the amount of physical activity occurring in the rear seat of the vehicle while allowing the officer to safely stop the vehicle. The air bag can also provide the officer additional time to get backup personnel to aid him if the situation warrants it. The bag is inflated and maintains a constant pressure by an air pump. 8 figs.

  10. Air bag restraint device

    DOEpatents

    Marts, Donna J.; Richardson, John G.

    1995-01-01

    A rear-seat air bag restraint device is disclosed that prevents an individual, or individuals, from continuing violent actions while being transported in a patrol vehicle's rear seat without requiring immediate physical contact by the law enforcement officer. The air bag is activated by a control switch in the front seat and inflates to independently restrict the amount of physical activity occurring in the rear seat of the vehicle while allowing the officer to safely stop the vehicle. The air bag can also provide the officer additional time to get backup personnel to aid him if the situation warrants it. The bag is inflated and maintains a constant pressure by an air pump.

  11. Corrosion behavior of carbon steel in the monoethanolamine-H{sub 2}O-CO{sub 2}-O{sub 2}-SO{sub 2} System: products, reaction pathways, and kinetics

    SciTech Connect

    Kladkaew, N.; Idem, R.; Tontiwachwuthikul, P.; Saiwan, C.

    2009-12-15

    This work investigates the effect of operating parameters on corrosion products, reaction pathways, and kinetics For the corrosion of carbon steel in the monoethanolamine-H{sub 2}O-CO{sub 2}-O{sub 2}-SO{sub 2} system. Corrosion experiments were conducted using a 273A potentiostat unit under conditions in which monoethanolamine (MEA), O{sub 2}, and SO{sub 2} concentrations and CO{sub 2} loading were in the range of 1-7 kmol/m{sup 3}, 0-100%, 0-204 ppm, and 0-0.5 mol CO{sub 2}/mol MEA, respectively, at corrosion temperatures of 303-353 K to mimic the absorption-regeneration sections. Analysis, performed for this system for the first time, shows that corrosion products generated from the effect of SO{sub 2} include FeSO{sub 4} and Fe{sub 2}O{sub 3} {center_dot} H{sub 2}O. Also, a higher concentration of SO{sub 2} in simulated flue gas stream induces a higher corrosion rate because of the increase in the hydrogen ion concentration generated by reactions of SO{sub 2} and H{sub 2}O as well as SO{sub 2}, O{sub 2}, and H{sub 2}O. A power-law model developed to correlate corrosion rate with the parameters in the MEA-H{sub 2}O-CO{sub 2}-O{sub 2}-SO{sub 2} system shows that corrosion rate of carbon steel increases with an increase in O{sub 2} and SO{sub 2} concentrations in simulated flue gas stream, as well as MEA concentration, CO{sub 2} loading, and operating temperature. It was observed that CO{sub 2} loading had the highest impact on the corrosion rate, while SO{sub 2} and O{sub 2} show only slight effects on the corrosion rate.

  12. Development of autoclavable addition type polyimides

    NASA Technical Reports Server (NTRS)

    Jones, R. J.; Vaughan, R. W.; Orell, M. K.; Sheppard, C. H.

    1974-01-01

    Two highly promising approaches to yield autoclavable addition-type polyimides were identified and evaluated in the program. Conditions were established for autoclave preparation of Hercules HMS graphite fiber reinforced composites in the temperature range of 473 K to 505 K under an applied pressure of 0.7 MN/m2 (100 psi) for time durations up to four hours. Upon oven postcure in air at 589 K, composite samples demonstrated high mechanical property retention at 561 K after isothermal aging in air for 1000 hours. Promise was shown for shorter term mechanical property retention at 589 K upon exposure in air at this temperature.

  13. Trends in visibility, PM{sub 2.5}, and deposition expected from the Acid Rain Provisions of the 1990 Clean Air Act Amendments

    SciTech Connect

    Shannon, J.D.; Hanson, D.A.

    1997-08-01

    The Acid Rain Provisions (Title IV) of the 1990 Clean Air Act Amendments (CAAA) are designed to reduce the deposition of SO{sub 2} and sulfate and, to a lesser extent, the deposition of NO{sub x} and nitrate through reduction of SO{sub 2} and NO{sub x} emissions. However, other important benefits are anticipated from the emission control strategies, including improvement of regional visibility and reductions in concentrations of fine particles (PM2.5). In this study, the authors coupled utility emissions forecasts with the Advanced Statistical Trajectory Regional Air Pollution (ASTRAP) model and the Visibility Assessment Scoping Model (VASM) to calculate and compare the relative improvements by 2010 in visual impairment, PM2.5 concentrations, and sulfate wet deposition at selected sites in the eastern United States.

  14. Interaction of low-expansion NZP ceramics with Na{sub 2}SO{sub 4} at 1000{degrees}C

    SciTech Connect

    Lee, W.Y.; Cooley, K.M.; Stinton, D.P.; Joslin, D.L.

    1996-08-01

    The interaction between several low-expansion NZP materials and Na{sub 2}SO{sub 4} at 1000{degrees}C in pure O{sub 2} was studied. Ba{sub 1.25}Zr{sub 4}P{sub 5.5}Si{sub 0.5}O{sub 24} experienced extensive cracking and delamination upon reaction with Na{sub 2}SO{sub 4}. On the other hand, Ca{sub 0.5}Sr{sub 0.5}Zr{sub 4}P{sub 6}O{sub 24} remained intact in terms of visual appearance, and had no significant weight loss or gain. However, the ion exchange between Na{sup +} ions and Ca{sup +2} ions was observed to be sufficiently rapid to allow the penetration of the Na{sup +} ions into the test specimens in 100h. The segregation of Ca to the specimen surface was observed due to the ion exchange. Ca{sub 0.6}Mg{sub 0.4}Zr{sub 4}P{sub 6}O{sub 24} was also tested, but its stability could not properly be assessed because the as-received specimens contained a significant amount of MgZr{sub 4}P{sub 6}O{sub 24} as an impurity phase.

  15. Effect of pollutant dose on the response of Mexican bean beetle (Coleoptea: Coccinellidae) to SO/sub 2/-induced changes in soybean

    SciTech Connect

    Hughes, P.R.; Chiment, J.J.; Dickie, A.I.

    1985-12-01

    Larvae of the Mexican bean beetle, Epilachna varivestis Mulsant, grew larger when fed on soybean foliage fumigated for 24 h with SO/sub 2/ at concentrations of 131 to 1834 ..mu..g m/sup -3/ than when fed on nonfumigated leaves. Relative weight gain was not linear against SO/sub 2/ concentration in the range sampled; it was greatest when leaves were fumigated with ca. 786 ..mu..g m/sup -3/ and less pronounced at either higher or lower concentrations. Smaller relative weight gains, also having a maximum at a concentration of approximately 786 ..mu..g m/sup -3/, were found when larvae were reared on foliage allowed 24 h in which to recover from fumigation. No effect on growth was observed when plants were fumigated with 65 ..mu..g m/sup -3/, indicating a threshold for effect between 65 and 131 ..mu..g m/sup -3/ under the conditions of these tests. Change in the plant induced by fumigation, as indicated by growth response of the insects, was rapid, occurring in less than 6 h when plants were fumigated at a concentration of 1310 ..mu..g m/sup -3/; recovery of the plant from an exposure was slow relative to response time.

  16. Interaction of low-expansion NZP ceramics with Na{sub 2}SO{sub 4} at 1000{degrees}C

    SciTech Connect

    Lee, W.Y.; Stinton, D.P.; Joslin, D.L.

    1996-06-01

    The interaction between several low-expansion NZP materials and Na{sub 2}SO{sub 4} at 1000{degrees}C in pure O{sub 2} was studied. Ba{sub 1.25}Zr{sub 4}P{sub 5.5}Si{sub 0.5}O{sub 24} experienced extensive cracking and delamination upon reaction with Na{sub 2}SO{sub 4}. On the other hand, Ca{sub 0.5}Sr{sub 0.5}Zr{sub 4}P{sub 6}O{sub 24} remained intact in terms of visual appearance, and had no significant weight loss or gain. However, the ion exchange between Na{sup +} ions and Ca{sup +2} ions was observed to be sufficiently rapid to allow the penetration of the Na{sup +} ions into the test specimens in 100 h. The segregation of Ca to the specimen surface was observed due to the ion exchange. Ca{sub 0.6}Mg{sub 0.4}Zr{sub 4}P{sub 6}O{sub 24} was also tested, but its stability could not properly be assessed because the as-received specimens contained a significant amount of MgZr{sub 4}P{sub 6}O{sub 24} as an impurity phase.

  17. Kinetics of Mn{sub 2}O{sub 3} digestion in H{sub 2}SO{sub 4} solutions

    SciTech Connect

    Walanda, Daud K.; Lawrance, Geoffrey A.; Donne, Scott W.

    2009-06-15

    The kinetics of Mn{sub 2}O{sub 3} digestion in various H{sub 2}SO{sub 4} solutions (0.5-2.0 M) and at various temperatures (ambient to 80 deg. C) to form solid gamma-MnO{sub 2} and soluble Mn(II) have been examined using X-ray diffraction. Using a modified first-order Avrami expression to describe digestion kinetics, rate constants in the range 0.02-0.98 h{sup -1} were found for Mn{sub 2}O{sub 3} disappearance, and 0.03-0.42 h{sup -1} for gamma-MnO{sub 2} formation, with higher H{sub 2}SO{sub 4} concentrations and temperatures leading to faster conversion rates. Also, for a particular set of experimental conditions, the rate of gamma-MnO{sub 2} formation was always slower than Mn{sub 2}O{sub 3} disappearance. This was interpreted in terms of the solubility and stability of the soluble Mn(III) intermediated formed during the digestion. Activation energies for Mn{sub 2}O{sub 3} dissolution and gamma-MnO{sub 2} formation were also determined. - Graphical Abstract: Manganese dioxide phase diagram resulting from the acid digestion of Mn{sub 2}O{sub 3}.

  18. Efficiency of buffered aqueous carboxylic acid solutions and organic solvents to absorb SO/sub 2/ from industrial flue gas; solubility data from gas-liquid chromatography

    SciTech Connect

    Sanza, G.J.

    1982-01-01

    Nine adsorbents were examined. These potential candidates for flue gas desulfurization included 1-methyl-2-pyrrolidinone, tri-n-butyl phosphate (TBP), both 0.5 M and 1.0 M solutions of citric acid and glycolic acid, buffered to pH's of 4.5 and 3.8, and pure water. Infinite dilution activity coefficients of SO/sub 2/ were obtained by gas-liquid chromatography in a trial solvent of Nitrobenzene, and then in systems of 1-methyl-2-pyrrolidinone and TBP, independently. The solubility data of SO/sub 2/ was derived and found to be comparable to data obtained from a classical bubble-sparger apparatus. Solubility data was then programmed into an absorber-stripper computer simulator in order to calculate the various concentration and temperature profiles that would exist, the degree of desulfurization, and the steam consumption for all nine systems. Concentrated solutions of citric acid buffered to a low pH exhibited the most favorable conditions for application in direct steam regeneration processes. 1-methyl-2-pyrrolidinone yielded better performance than TBP did with high-pressure indirect steam used for stripping. Comparison between the aqueous solution systems which employed direct steam, and the organic systems which used indirect steam was inconclusive.

  19. Anti-misting additives for jet fuels

    NASA Technical Reports Server (NTRS)

    Grens, E. A., II; Williams, M. C.

    1982-01-01

    The ignition characteristics of sprays, created by wind shear action, of Jet-A fuel containing polyisobutylene additives wee examined over ranges of air velocities from 45 to 90 m/s and of fuel/air mass ratios of 0.20 to 8.0. Ignition was by calibrated sparks of energies up to about 0.5 J and by a butane/oxygen flame at 165 J/s. The polymeric additives studied included the grades L80, L160, and L200 from Exxon Chemical and B200 and B230 from BASF. The ignition suppression ability of the additives, as well as their observed anti-misting (AM) behavior, ranked exactly as their molecular weights (viscosity average, M sub v) with 400-500 ppm of L80 (M sub v = 0.68 x 1,000,000) being required to suppress ignition of a spray at 51 m/s, 1.8 fuel/air mass ratio, by a 0.55 J spark while only 10 ppm of B230 (M sub v = 7.37 x 1,000,000) was required for the same conditions. The additive concentrations (L160) required for ignition suppression increased with increasing air velocity and with increasing fuel/air ratio.

  20. An investigation of infiltration and indoor air quality

    SciTech Connect

    Not Available

    1990-09-01

    A multitask study was performed in the State of New York to provide information for guiding home energy conservation programs while maintaining acceptable indoor air quality. During this study, the statistical distribution of radon concentrations inside 2400 homes was determined. The relationships among radon levels, house characteristics, and sources were also investigated. The direct impact that two specific air infiltration reduction measures -- caulking and weatherstripping of windows and doors, and installation of storm windows and storm doors -- have on house air leakage was investigated in 60 homes. The effect of house age on the impact of weatherization was also evaluated. Indoor and outdoor measurements of NO{sub 2}, CO, SO{sub 2}, and respirable suspended particulates (RSP) were made for 400 homes to determine the effect of combustion sources on indoor air quality and to characterize the statistical distribution of the concentrations. Finally, the combustion source data were combined with the information on air infiltration reduction measures to estimate the potential impact of these measures on indoor air quality. 87 tabs.

  1. Air Pollution

    MedlinePlus

    ... tobacco smoke. How is air pollution linked to climate change? While climate change is a global process, it ... ozone levels are also a concern. Impacts of Climate Change on Human Health in the United States: A ...

  2. Air Apparent.

    ERIC Educational Resources Information Center

    Harbster, David A.

    1988-01-01

    Explains the principle upon which a barometer operates. Describes how to construct two barometric devices for use in the classroom that show air's changing pressure. Cites some conditions for predicting weather. (RT)

  3. Micronized coal-fired retrofit system for SO{sub x} reduction - Krakow Clean Fossil Fuels and Energy Efficiency Program.

    SciTech Connect

    1996-09-30

    the project proposes to install a new TCS micronized coal-fired heating plant for the Produkcja I Hodowla Roslin Ogrodniczych (PHRO) Greenhouse Complex, Krzeszowice, Poland (about 20 miles west of Krakow). PHRO currently utilizes 14 heavy oil-fired boilers to produce heat for its greenhouse facilities and also home heating to several adjacent apartment housing complexes. The boilers currently burn a high-sulfur content heavy crude oil, called Mazute. The micronized coal fired boiler would (1) provide a significant portion of the heat for PHRO and a portion of the adjacent apartment housing complexes, (2) dramatically reduce sulfur dioxide air pollution emission, while satisfying new Polish air regulations, and (3) provide attractive savings to PHRO, based on the quantity of displaced oil.

  4. [Food additives and healthiness].

    PubMed

    Heinonen, Marina

    2014-01-01

    Additives are used for improving food structure or preventing its spoilage, for example. Many substances used as additives are also naturally present in food. The safety of additives is evaluated according to commonly agreed principles. If high concentrations of an additive cause adverse health effects for humans, a limit of acceptable daily intake (ADI) is set for it. An additive is a risk only when ADI is exceeded. The healthiness of food is measured on the basis of nutrient density and scientifically proven effects. PMID:24772784

  5. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. R.; St. Clair, T. L.; Burks, H. D.; Stoakley, D. M.

    1987-01-01

    A method has been found for enhancing the melt flow of thermoplastic polyimides during processing. A high molecular weight 422 copoly(amic acid) or copolyimide was fused with approximately 0.05 to 5 pct by weight of a low molecular weight amic acid or imide additive, and this melt was studied by capillary rheometry. Excellent flow and improved composite properties on graphite resulted from the addition of a PMDA-aniline additive to LARC-TPI. Solution viscosity studies imply that amic acid additives temporarily lower molecular weight and, hence, enlarge the processing window. Thus, compositions containing the additive have a lower melt viscosity for a longer time than those unmodified.

  6. Volcanic gas emissions and their impact on ambient air character at Kilauea Volcano, Hawaii

    SciTech Connect

    Sutton, A.J.; Elias, T.; Navarrete, R.

    1994-12-31

    Gas emissions from Kilauea occur from the summit caldera, along the middle East Rift Zone (ERZ), and where lava enters the ocean. We estimate that the current ERZ eruption of Kilauea releases between 400 metric tonnes of SO{sub 2} per day, during eruptive pauses, to as much as 1850 metric tonnes per day during actively erupting periods, along with lesser amounts of other chemically and radiatively active species including H{sub 2}S, HCl and HF. In order to characterize gas emissions from Kilauea in a meaningful way for assessing environmental impact, we made a series of replicate grab-sample measurements of ambient air and precipitation at the summit of Kilauea, along its ERZ, and at coastal sites where lava enters the ocean. The grab-sampling data combined with SO{sub 2} emission rates, and continuous air quality and meteorological monitoring at the summit of Kilauea show that the effects of these emissions on ambient air character are a complex function of chemical reactivity, source geometry and effusivity, and local meteorology. Prevailing tradewinds typically carry the gases and aerosols released to the southwest, where they are further distributed by the regional wind regime. Episodes of kona, or low speed variable winds sometimes disrupt this pattern, however, and allow the gases and their oxidation products to collect at the summit and eastern side of the island. Summit solfatara areas of Kilauea are distinguished by moderate to high ambient SO{sub 2}, high H{sub 2}S at one location, and low H{sub 2}S at all others, and negligible HCl concentrations, as measured 1 m from degassing point-sources. Summit solfatara rain water has high sulfate and low chloride ion concentrations, and low pH.

  7. Additive usage levels.

    PubMed

    Langlais, R

    1996-01-01

    With the adoption of the European Parliament and Council Directives on sweeteners, colours and miscellaneous additives the Commission is now embarking on the project of coordinating the activities of the European Union Member States in the collection of the data that are to make up the report on food additive intake requested by the European Parliament. This presentation looks at the inventory of available sources on additive use levels and concludes that for the time being national legislation is still the best source of information considering that the directives have yet to be transposed into national legislation. Furthermore, this presentation covers the correlation of the food categories as found in the additives directives with those used by national consumption surveys and finds that in a number of instances this correlation still leaves a lot to be desired. The intake of additives via food ingestion and the intake of substances which are chemically identical to additives but which occur naturally in fruits and vegetables is found in a number of cases to be higher than the intake of additives added during the manufacture of foodstuffs. While the difficulties are recognized in contributing to the compilation of food additive intake data, industry as a whole, i.e. the food manufacturing and food additive manufacturing industries, are confident that in a concerted effort, use data on food additives by industry can be made available. Lastly, the paper points out that with the transportation of the additives directives into national legislation and the time by which the food industry will be able to make use of the new food legislative environment several years will still go by; food additives use data by the food industry will thus have to be reviewed at the beginning of the next century. PMID:8792135

  8. An additional middle cuneiform?

    PubMed Central

    Brookes-Fazakerley, S.D.; Jackson, G.E.; Platt, S.R.

    2015-01-01

    Additional cuneiform bones of the foot have been described in reference to the medial bipartite cuneiform or as small accessory ossicles. An additional middle cuneiform has not been previously documented. We present the case of a patient with an additional ossicle that has the appearance and location of an additional middle cuneiform. Recognizing such an anatomical anomaly is essential for ruling out second metatarsal base or middle cuneiform fractures and for the preoperative planning of arthrodesis or open reduction and internal fixation procedures in this anatomical location. PMID:26224890

  9. Air surveillance

    SciTech Connect

    Patton, G.W.

    1995-06-01

    This section of the 1994 Hanford Site Environmental Report summarizes the air surveillance and monitoring programs currently in operation at that Hanford Site. Atmospheric releases of pollutants from Hanford to the surrounding region are a potential source of human exposure. For that reason, both radioactive and nonradioactive materials in air are monitored at a number of locations. The influence of Hanford emissions on local radionuclide concentrations was evaluated by comparing concentrations measured at distant locations within the region to concentrations measured at the Site perimeter. This section discusses sample collection, analytical methods, and the results of the Hanford air surveillance program. A complete listing of all analytical results summarized in this section is reported separately by Bisping (1995).

  10. Air Cleaning Technologies

    PubMed Central

    2005-01-01

    Executive Summary Objective This health technology policy assessment will answer the following questions: When should in-room air cleaners be used? How effective are in-room air cleaners? Are in-room air cleaners that use combined HEPA and UVGI air cleaning technology more effective than those that use HEPA filtration alone? What is the Plasmacluster ion air purifier in the pandemic influenza preparation plan? The experience of severe acute respiratory syndrome (SARS) locally, nationally, and internationally underscored the importance of administrative, environmental, and personal protective infection control measures in health care facilities. In the aftermath of the SARS crisis, there was a need for a clearer understanding of Ontario’s capacity to manage suspected or confirmed cases of airborne infectious diseases. In so doing, the Walker Commission thought that more attention should be paid to the potential use of new technologies such as in-room air cleaning units. It recommended that the Medical Advisory Secretariat of the Ontario Ministry of Health and Long-Term Care evaluate the appropriate use and effectiveness of such new technologies. Accordingly, the Ontario Health Technology Advisory Committee asked the Medical Advisory Secretariat to review the literature on the effectiveness and utility of in-room air cleaners that use high-efficiency particle air (HEPA) filters and ultraviolet germicidal irradiation (UVGI) air cleaning technology. Additionally, the Ontario Health Technology Advisory Committee prioritized a request from the ministry’s Emergency Management Unit to investigate the possible role of the Plasmacluster ion air purifier manufactured by Sharp Electronics Corporation, in the pandemic influenza preparation plan. Clinical Need Airborne transmission of infectious diseases depends in part on the concentration of breathable infectious pathogens (germs) in room air. Infection control is achieved by a combination of administrative, engineering

  11. Modeling uranium transport in acidic contaminated groundwater with base addition

    SciTech Connect

    Zhang, Fan; Luo, Wensui; Parker, Jack C.; Brooks, Scott C; Watson, David B; Jardine, Philip; Gu, Baohua

    2011-01-01

    This study investigates reactive transport modeling in a column of uranium(VI)-contaminated sediments with base additions in the circulating influent. The groundwater and sediment exhibit oxic conditions with low pH, high concentrations of NO{sub 3}{sup -}, SO{sub 4}{sup 2-}, U and various metal cations. Preliminary batch experiments indicate that additions of strong base induce rapid immobilization of U for this material. In the column experiment that is the focus of the present study, effluent groundwater was titrated with NaOH solution in an inflow reservoir before reinjection to gradually increase the solution pH in the column. An equilibrium hydrolysis, precipitation and ion exchange reaction model developed through simulation of the preliminary batch titration experiments predicted faster reduction of aqueous Al than observed in the column experiment. The model was therefore modified to consider reaction kinetics for the precipitation and dissolution processes which are the major mechanism for Al immobilization. The combined kinetic and equilibrium reaction model adequately described variations in pH, aqueous concentrations of metal cations (Al, Ca, Mg, Sr, Mn, Ni, Co), sulfate and U(VI). The experimental and modeling results indicate that U(VI) can be effectively sequestered with controlled base addition due to sorption by slowly precipitated Al with pH-dependent surface charge. The model may prove useful to predict field-scale U(VI) sequestration and remediation effectiveness.

  12. The role of integrated resource planning, environmental externalities, and anticipation of future regulation in compliance planning under the Clean Air Act Amendments of 1990

    SciTech Connect

    Bernow, S.; Biewald, B.; Wulfsberg, K.

    1993-07-01

    Utilities are developing sulfur dioxide (SO{sub 2}) emission compliance plans to meet limitations of the Clean Air Act Amendments of 1990 (CAAA). Compliance plans will have long-term effects on resource selection, fuel choice, and system dispatch. Use of integrated resource planning (IRP) is necessary to ensure compliance plans are consistent with the overall societal goals. In particular, environmental externalities must be integrated with the compliance planning process. The focus of the CAAA is on air pollution reduction, specifically acid gases and toxics, and attainment of National Ambient Air Quality Standards (NAAQS) for criteria pollutants. Title IV specifically focuses on sulfur dioxide with a national allowance trading system, while further regulation of toxics and nitrogen oxides is slated for additional study. Yet, compliance planning based narrowly upon today`s environmental regulations could fail to meet the broad goals of IRP if a larger array of environmental externalities is excluded from the analysis. Compliance planning must consider a broad range of environmental effects from energy production and use to (1) protect society`s long-term stake in environmental quality, and (2) ensure that today`s plans are rich enough to accommodate potential changes in regulation and national environmental goals. The explicit recognition of environmental effects, such as those associated with CO{sub 2} release, will result in prudent compliance plans that take advantage of current opportunities for pollution avoidance and have long-term viability in the face of regulatory change. By including such considerations, the mix of resources acquired and operated (supply and demand, existing and new, conventional and renewable, fuel type and fuel quality, pollution control, and dispatch protocols) will be robust and truly least-cost.

  13. Chemical compositions responsible for inflammation and tissue damage in the mouse lung by coarse and fine particulate samples from contrasting air pollution in Europe

    SciTech Connect

    Happo, M.S.; Hirvonen, M.R.; Halinen, A.I.; Jalava, P.I.; Pennanen, A.S.; Sillanpaa, M.; Hillamo, R.; Salonen, R.O.

    2008-07-01

    Inflammation is regarded as an important mechanism in mortality and morbidity associated with exposures of cardiorespiratory patients to urban air particulate matter. We investigated the association of the chemical composition and sources of urban air fine (PM2.5-0.2) and coarse (PM10-2.5) particulate samples with the inflammatory activity in the mouse lung. The particulate samples were collected during selected seasons in six European cities using a high-volume cascade impactor. Healthy C57BL/6J mice were intratracheally instilled with a single dose (10 mg/kg) of the particulate samples. At 4, 12, and 24 h after the exposure, the lungs were lavaged and the bronchoalveolar lavage fluid (BALF) was assayed for indicators of inflammation and tissue damage: cell number, total protein, and cytokines (tumor necrosis factor (TNF)-alpha, interleukin (IL)-6, and KC). Dicarboxylic acids and transition metals, especially Ni and V, in PM2.5-0.2 correlated positively and some secondary inorganic ions (NO{sub 3}{sup -}, NH{sub 4}{sup +}) negatively with the inflammatory activity. Total organic matter and SO{sub 4}{sup 2-} had no consistent correlations. In addition, the soil-derived constituents (Ca{sup 2+}, Al, Fe, Si) showed positive correlations with the PM2.5-0.2-induced inflammatory activity, but their role in PM10 (2.5) remained obscure, possibly due to largely undefined biogenic material. Markers of poor biomass and coal combustion, i.e., monosaccharide anhydrides and As, were associated with elevated PAH contents in PM2.5 (0.2) and a consistent immunosuppressive effect. Overall, our results support epidemiological findings that the local sources of incomplete combustion and resuspended road dust are important in urban air particulate pollution-related health effects.

  14. Nanoparticles of K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3}:Eu as effective detectors for swift heavy ions

    SciTech Connect

    Salah, Numan; Lochab, S. P.; Kanjilal, D.; Ranjan, Ranju; Habib, Sami S.; Rupasov, A. A.; Aleynikov, V. E.

    2007-09-15

    The modification of thermoluminescence (TL) and photoluminescence (PL) properties of K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3}:Eu nanoparticles by swift heavy ions (SHI), irradiation is studied. Pellets form of the nanomaterials were irradiated by 48 MeV Li{sup 3+}, 75 MeV C{sup 6+}, and 90 MeV O{sup 7+} ion beams. The fluence range is 1x10{sup 9}-1x10{sup 13} ions/cm{sup 2}. The modification in TL glow curves of the nanomaterials irradiated by Li{sup 3+}, C{sup 6+}, and O{sup 7+} ion beams are essentially similar to those induced by {gamma}-ray irradiation. These glow curves have single peaks at around 427 K with a small variation in their positions by around {+-}3 K. The TL intensity of the ion beams irradiated nanomaterials is found to decease, while going from low to high atomic number (Z) ions (i.e., Li{sup 3+}{yields}O{sup 7+}). The TL response curve of the pellets irradiated by Li{sup 3+} ions is linear in the whole range of studied fluences. The curves for C{sup 6+} and O{sup 7+} irradiated samples are linear at lower fluences (1x10{sup 9}-1x10{sup 12} ion/cm{sup 2}) and then saturate at higher fluence. These results for the nanomaterials are much better than that of the corresponding microcrystalline samples irradiated with a Li{sup 3+} ion. The curves were linear up to the fluence 1x10{sup 11} ion/cm{sup 2} and then become sublinear at higher fluences. The TL efficiency values of K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3}:Eu nanoparticles irradiated by 48 MeV Li{sup 3+}, 75 MeV C{sup 6+}, and 90 MeV O{sup 7+} ion beams have been measured relative to {gamma} rays of {sup 60}Co and are found to be 0.515, 0.069, and 0.019, respectively. This value for the Li{sup 3+} ion (0.515) is much higher than that of the corresponding microcrystalline material (0.0014). These superiorities for the nanomaterials make K{sub 2}Ca{sub 2}(SO{sub 4}){sub 3}:Eu nanophosphor a suitable candidate for detecting the doses of swift heavy ions. PL studies on the ion beams irradiated and

  15. The impact of SO/sub 2/ on potatoes chronically stressed with ozone. Final report April 1978-August 1979

    SciTech Connect

    Foster, K.W.

    1980-11-01

    Potato crops in the San Joaquin Valley of California may be damaged by air pollution, specifically ozone and/or sulfur dioxide. Experiments at the University of California, Riverside, were conducted to examine the effects of four levels of ambient oxidant treatment in factorial combination with two levels of sulfur dioxide treatment on yield and quality of 'Centennial', a russet-skinned cultivar. Root and shoot dry weights and tuber yield were linearly reduced by oxidant treatments. Sulfur dioxide effects were less marked but of possible importance. No treatment effects on dry matter or sugar contents of tubers were observed.

  16. 48 CFR 228.370 - Additional clauses.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...., helicopters, vertical take-off or landing aircraft, lighter-than-air airships, unmanned aerial vehicles, or... 48 Federal Acquisition Regulations System 3 2012-10-01 2012-10-01 false Additional clauses. 228.370 Section 228.370 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS...

  17. 48 CFR 228.370 - Additional clauses.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...., helicopters, vertical take-off or landing aircraft, lighter-than-air airships, unmanned aerial vehicles, or... 48 Federal Acquisition Regulations System 3 2011-10-01 2011-10-01 false Additional clauses. 228.370 Section 228.370 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS...

  18. 48 CFR 228.370 - Additional clauses.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...., helicopters, vertical take-off or landing aircraft, lighter-than-air airships, unmanned aerial vehicles, or... 48 Federal Acquisition Regulations System 3 2013-10-01 2013-10-01 false Additional clauses. 228.370 Section 228.370 Federal Acquisition Regulations System DEFENSE ACQUISITION REGULATIONS...

  19. 76 FR 65501 - Procurement List Additions

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-21

    ...: Grounds Maintenance, Air Force Research Laboratory Stockbridge Test Facility, 5251 Burleson Road, Oneida... INFORMATION: Additions On 8/19/2011 (76 FR 51955-51956) and 8/26/2011 (76 FR 53419-53420), the Committee for..., FA8751 AFRL RIKO, Rome, NY. Patricia Briscoe, Deputy Director, Business Operations, Pricing...

  20. Proceedings of the Air & Waste Management Association's (A & WMA) 100th annual conference and exhibition

    SciTech Connect

    2007-07-01

    The CD-ROM contains more than 500 full technical presentations from the Air and Waste Management Association's 100th Annual Conference. The 2007 Critical Review 'Will the circle be unbroken? A history of the US national ambient air quality standards' is also included, as well as articles celebrating A & WMA's centennial. Subjects covered include: PM field studies; fine particles; PM measurements; chemical composition of the atmosphere; photochemical process in the atmosphere; short range dispersion; regional model analysis; long range dispersion modeling; noises and vibration; visibility; indoor air quality chemistry and physics; SO{sub 3} and SO{sub 2} control techniques; NOx control; mercury and power generation, technology and control; mercury emissions control, measurement and science; PM2.5 fine particle emission control; CO{sub 2} capture from combustion sources; innovations in control of VOCs and other hazardous emissions; organic vapor capture for recovery, recycling or destruction; biological control of emissions; computer generated inventories; ambient monitoring field studies; satellite remote sensing; MACT developments; particulate matter; environmental compliance at Federal facilities; mercury monitoring in the power generation industry; coal plant and IGCC regulatory and permitting issues; environmental issues facing industry energy; climate change electric power industry perspectives; and climate change and sustainability shortages.

  1. Carbamate deposit control additives

    SciTech Connect

    Honnen, L.R.; Lewis, R.A.

    1980-11-25

    Deposit control additives for internal combustion engines are provided which maintain cleanliness of intake systems without contributing to combustion chamber deposits. The additives are poly(oxyalkylene) carbamates comprising a hydrocarbyloxyterminated poly(Oxyalkylene) chain of 2-5 carbon oxyalkylene units bonded through an oxycarbonyl group to a nitrogen atom of ethylenediamine.

  2. Comparative study of the reactions of metal oxides and carbonates with H{sub 2}S and SO{sub 2}. Final technical report, September 1990--February 1994

    SciTech Connect

    Sotirchos, S.V.

    1994-03-01

    The primary objective of this project had been the investigation of the effects of pore structure on the capacity of porous metal oxides for removal of gaseous pollutants from flue gases of power plants (SO{sub 2}) and hot coal gas (primarily H{sub 2}S). Porous calcines obtained from natural precursors (limestones and dolomites) and sorbents based on zinc oxide were used as model systems in our experimental studies, which included reactivity evolution experiments and pore structure characterization using a variety of methods. The key idea behind this project was to appropriately exploit the differences of the sulfidation and sulfation reactions (for instance, different molar volumes of solid products) to elucidate the dependence of the sorptive capacity of a porous sorbent on its physical microstructure. In order to be able to proceed faster and more productively on the analysis of the above defined problem, it was decided to employ in our studies solids whose reaction with SO{sub 2} (limestone calcines) or H{sub 2}S (sorbents based on zinc oxide) had been investigated in detail in past studies by our research group. Reactivity vs time or conversion vs time studies were conducted using thermogravimetry and fixed-bed and fluidized-bed reactors. The pore structure of partially reacted samples collected at selected time instants or conversion levels was analyzed by gas adsorption and mercury porosimetry. For better characterization of the pore structure of the solid samples, we also carried out intraparticle diffusivity measurements by the peak-broadening (chromatographic) method, using a system developed for this purpose in our laboratory. In the context of this part of the project, we also conducted a detailed theoretical investigation of the measurement of effective diffusivities in porous solids using the diffusion-cell method.

  3. Allowance trading under the Clean Air Act: Who should regulate, and when?

    SciTech Connect

    Lock, R.

    1993-07-01

    The goal of this paper is to explore how compliance with the Clean Air Act Amendments of 1990 (CAAA), especially Title IV and emission trading under it, will affect the current relationship between state and federal regulation. It is difficult, with the limited experience we have had under Title IV, to be definitive about or to be a very strong advocate of too many policy positions. What may be most helpful at this point is to identify where the difficult issues in state/federal relations might arise; and then to explore ways in which tensions might be either avoided or resolved. One anticipated conclusion is that a traditional regulatory mindset could be very destructive if applied to this new area of oversight without due sensitivity to what Congress is trying to achieve in Title IV. That concern pervaded the early legislative debates; and it persists today. Title IV presents some unique challenges to state regulators and will require some creative solutions and fresh thinking if the goals of Congress are to be realized and the full benefits that allowance trading can offer are to be reaped by electricity consumers. In the ultimate analysis, Title IV amounts to a massive internalization of the external costs imposed on society by acid rain deposition. (This places in serious question the notion of additional externality {open_quotes}adders{close_quotes} for sulfur dioxide (SO{sub 2}) and nitrous oxide (NO{sub x}) at the state level for utility supply planning purposes.) The whole point of Title IV is to give those directly charged with compliance, namely power producers, the maximum flexibility to pursue least-cost compliance solutions. Perhaps the biggest single factor in how well they do this will be how state regulators respond to their compliance and allowance trading initiatives.

  4. Enhanced electrochemical performances of PANI using redox additive of K{sub 4}[Fe(CN){sub 6}] in aqueous electrolyte for symmetric supercapacitors

    SciTech Connect

    Shanmugavani, A.; Kaviselvi, S.; Sankar, K.Vijaya; Selvan, R.Kalai

    2015-02-15

    Highlights: • Effect of K{sub 4}[Fe(CN){sub 6}] in H{sub 2}SO{sub 4} studied on the electrochemical properties of PANI. • The polaron band – π* transition reveals the emeraldine salt (conductive) form. • CV curves exhibit quasi-reversible redox behavior. • Symmetric PANI SC shows 228 F g{sup −1} at 1 mA cm{sup −2} in K{sub 4}[Fe (CN){sub 6}] added 1 M H{sub 2}SO{sub 4}. • PANI-1 symmetric supercapacitor shows almost 100% of capacity retention. - Abstract: Polyaniline (PANI) particles were prepared by reflux assisted chemical oxidative polymerization method with the aid of ammonium per sulfate/ferric chloride as oxidants and HCl/H{sub 2}SO{sub 4} as the medium. Amorphous nature and the emeraldine state of PANI were revealed from X-ray diffraction and Fourier transform infrared analysis. Moreover, ultra violet–visible spectra attributes to the polaron band – π* transition of polyaniline. The scanning electron microscopic image shows that the particle size is in the range of 0.2–2 μm. The electrochemical performances of the material were investigated in 1 M H{sub 2}SO{sub 4} and 0.08 M K{sub 4}[Fe(CN){sub 6}] added 1 M H{sub 2}SO{sub 4} aqueous electrolytes. Cyclic voltammetry and galvanostatic charge–discharge studies were carried out to find its suitability as a supercapacitor electrode material. The charge discharge analysis of the fabricated symmetric supercapacitors revealed the fact that the electrolyte containing redox additive (0.08 M K{sub 4}[Fe(CN){sub 6}]) delivered an enhanced specific capacitance of 228 F g{sup −1} (∼912 F g{sup −1} for single electrode) than that of 1 M H{sub 2}SO{sub 4} (100 F g{sup −1}) at 1 mA cm{sup −2}. Further cycling stability is performed at 5 mA cm{sup −2} ensures the durability of the supercapacitor.

  5. Air Pollution.

    ERIC Educational Resources Information Center

    Scorer, Richard S.

    The purpose of this book is to describe the basic mechanisms whereby pollution is transported and diffused in the atmosphere. It is designed to give practitioners an understanding of basic mechanics and physics so they may have a correct basis on which to formulate their decisions related to practical air pollution control problems. Since many…

  6. Air Pollution

    PubMed Central

    Clifton, Marjorie

    1964-01-01

    Dr Marjorie Clifton describes the classification of gaseous and nongaseous constituents of air pollution and then outlines the methods of measuring these. The National Survey embraced 150 towns of all sizes throughout England and Wales and provided data on smoke and sulphur dioxide in relation to climate, topography, industrialization, population density, fuel utilization and urban development. Dr W C Turner discusses the relationship between air pollution and mortality from respiratory conditions, and particularly the incidence of chronic bronchitis. He postulates a theory that such respiratory conditions arise as an allergy to the spores of certain moulds, spore formation being encouraged by the air humidity in Greatv Britain and overcrowded and damp living conditions. He describes the results of a twenty-week study undertaken in 1962-3, showing associations between respiratory disease and levels of air pollution. Dr Stuart Carne undertook a survey in general practice to plot the patterns of respiratory illness in London during the winter of 1962-3. There were two peaks of respiratory illnesses coinciding with the fog at the beginning of December and the freeze-up from the end of December until the beginning of March. PMID:14178955

  7. Air Trafficco

    ERIC Educational Resources Information Center

    Kasunic, Kevin

    1970-01-01

    The work of the 14,000 air traffic controllers can be both challenging and nerve-racking. Concentration, steady nerves, and a clear voice are required to remember the routing and identification of the maze of aircraft and to instruct each of them accurately. Controllers must have a high school diploma and three years work experience or a college…

  8. 40 CFR 79.24 - Termination of registration of additives.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... additives. 79.24 Section 79.24 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.24 Termination of registration of additives. Registration may be terminated by the Administrator if the...

  9. 40 CFR 79.24 - Termination of registration of additives.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... additives. 79.24 Section 79.24 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) REGISTRATION OF FUELS AND FUEL ADDITIVES Additive Registration Procedures § 79.24 Termination of registration of additives. Registration may be terminated by the Administrator if the...

  10. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Fletcher, James C. (Inventor); Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1992-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  11. Polyimide processing additives

    NASA Technical Reports Server (NTRS)

    Pratt, J. Richard (Inventor); St.clair, Terry L. (Inventor); Stoakley, Diane M. (Inventor); Burks, Harold D. (Inventor)

    1993-01-01

    A process for preparing polyimides having enhanced melt flow properties is described. The process consists of heating a mixture of a high molecular weight poly-(amic acid) or polyimide with a low molecular weight amic acid or imide additive in the range of 0.05 to 15 percent by weight of the additive. The polyimide powders so obtained show improved processability, as evidenced by lower melt viscosity by capillary rheometry. Likewise, films prepared from mixtures of polymers with additives show improved processability with earlier onset of stretching by TMA.

  12. Thermal properties and radiation damage in NaNH[sub 4]XO[sub 4][center dot]2H[sub 2]O single crystals (XO[sub 4] = SO[sub 4], SeO[sub 4])

    SciTech Connect

    Hilczer, B.; Szczepanska, L. ); Piskunowicz, P. ); Darwish, H.G. )

    1992-07-01

    Differential thermal analysis (DTA) studies of NaNH[sub 4]SO[sub 4][center dot]2H[sub 2]O, NaND[sub 4]SO[sub 4][center dot]2H[sub 2]O, and NANH[sub 4]SeO[sub 4][center dot]2H[sub 2]O single crystals were performed in the temperature range of the ferroelectric-paraelectric phase transition and of the dehydration process. The first-order phase transition at the Curie point was confirmed for NaNH[sub 4]SO[sub 4][center dot]2H[sub 2]O, whereas the transition in the isomorphous NaNH[sub 4]SeO[sub 4][center dot]2H[sub 2]O at the Curie temperature was found to be similar to a continuous (second order) with considerable higher transition enthalpy. Dehydration process of the crystals studied was found to proceed in two stages, with maximum dehydration rates at [approximately]355 and [approximately]400 K. A linear decrease in thermal energy related to the long-range ordering in NaNH[sub 4]SO[sub 4][center dot]2H[sub 2]O crystals was observed with the dose of [gamma]-cobalt-60 irradiation and discussed with respect to the radiation induced decrease in spontaneous polarization. 17 refs., 5 figs., 2 tabs.

  13. Air pollution source/receptor relationships in South Coast Air Basin, CA

    SciTech Connect

    Gao, N.

    1993-12-31

    This research project includes the application of some existing receptor models to study the air pollution source/receptor relationships in the South Coast Air Basin of southern California, the development of a new receptor model and the testing and the modifications of some existing models. These existing receptor models used include principal component factor analysis, potential source contribution function analysis, Kohonen`s neural network combined with Prim`s minimal spanning tree, and direct trilinear decomposition followed by a matrix reconstruction. The ambient concentration measurements used in this study are a subset of the data collected during the 1987 field exercise of Southern California Air Quality Study. It consists of a number of gaseous and particulate pollutants analyzed from samples collected by SCAQS samplers at eight sampling sites. Based on the information of emission inventories, meterology and ambient concentrations this receptor modeling study has revealed mechanisms that influence the air quality in SoCAB. Some of the mechanisms affecting the air quality in SoCAB that were revealed during this study include the following aspects. The SO{sub 2} collected at sampling sites is mainly contributed by refineries in the coastal area and the ships equipped with oil-fired boilers off shore. Combustion of fossil fuel by automobiles dominates the emission of NO{sub x} that is subsequently transformed and collected at sampling sites. Electric power plants also contribute HNO{sub 3} to the sampling sites. A large feedlot in the eastern region of SoCAB has been identified as the major source of NH{sub 3}. Possible contributions from other industrial sources such as smelters and incenerators were also revealed. The results of this study also suggest the possibility of DMS (dimethylsuflide) and NH{sub 3} emissions from off-shore sediments that have been contaminated by waste sludge disposal.

  14. Smog control fuel additives

    SciTech Connect

    Lundby, W.

    1993-06-29

    A method is described of controlling, reducing or eliminating, ozone and related smog resulting from photochemical reactions between ozone and automotive or industrial gases comprising the addition of iodine or compounds of iodine to hydrocarbon-base fuels prior to or during combustion in an amount of about 1 part iodine per 240 to 10,000,000 parts fuel, by weight, to be accomplished by: (a) the addition of these inhibitors during or after the refining or manufacturing process of liquid fuels; (b) the production of these inhibitors for addition into fuel tanks, such as automotive or industrial tanks; or (c) the addition of these inhibitors into combustion chambers of equipment utilizing solid fuels for the purpose of reducing ozone.

  15. Food Additives and Hyperkinesis

    ERIC Educational Resources Information Center

    Wender, Ester H.

    1977-01-01

    The hypothesis that food additives are causally associated with hyperkinesis and learning disabilities in children is reviewed, and available data are summarized. Available from: American Medical Association 535 North Dearborn Street Chicago, Illinois 60610. (JG)

  16. Additional Types of Neuropathy

    MedlinePlus

    ... A A Listen En Español Additional Types of Neuropathy Charcot's Joint Charcot's Joint, also called neuropathic arthropathy, ... can stop bone destruction and aid healing. Cranial Neuropathy Cranial neuropathy affects the 12 pairs of nerves ...

  17. Comparison of field data with a thermodynamic model for the H/sub 2/SO/sub 4/ - HNO/sub 3/ - NH/sub 3/ system at high humidities and in fogs

    SciTech Connect

    Jacob, D.J.; Munger, J.W.; Waldman, J.M.; Hoffmann, M.R.

    1986-04-01

    A systematic characterization of the atmospheric H/sub 2/SO/sub 4/ - NH/sub 2/ system was conducted in the fogwater, the aerosol, and the gas phase at a network of sites in the San Joaquin Valley of California. Spatial patterns of concentrations were established that reflect the distribution of SO/sub 2/, NO/sub X/, and NH/sub 3/ emissions within the valley. The concept of atmospheric alkalinity was introduced to interpret these concentrations in terms of the buffering capacity of the atmosphere with respect to inputs of strong acids. Regions of predominantly acidic and alkaline fogwater were identified. Fogwater was found to be alkaline in most of the valley, but small changes in emission budgets could lead to widespread acid fog. An extended stagnation episode was studied in detail: progressive accumulation of H/sub 2/SO/sub 4/ - HNO/sub 3/ - NH/sub 3/ species was documented over the course of the episode, and interpreted in terms of production and removal mechanisms. Secondary production of strong acids H/sub 2/SO/sub 4/ and HNO/sub 3/ under stagnant conditions resulted in a complete titration of available alkalinity at sites furthest from NH/sub 3/ sources. A steady SO/sub 2/ conversion rate of 0.4 - 1.1% h/sup -1/ was estimated in the stagnant mixed layer of haze aerosol under overcast conditions, and was attributed to non-photochemical heterogeneous processes. Removal of SO/sub 2/ was enhanced in fog as compared to non-foggy conditions. Conversion of NO/sub X/ to HNO/sub 3/ slowed down during the stagnation episode because of reduced photochemical activity: fog did not appear to enhance conversion of NO/sub X/. Decreases in total HNO/sub 3/ concentrations were observed upon acidification of the atmosphere, and were attributed to displacement of NO/sub 3-/ by H/sub 2/SO/sub 4/ in the aerosol followed by rapid deposition of HNO/sub 3/(g). The occurrence of fog was associated with general decreases of aerosol concentrations due to enhanced removal by deposition.

  18. Mortality from asthma and chronic bronchitis associated with changes in sulfur oxides air pollution

    SciTech Connect

    Imai, M.; Yoshida, K.; Kitabatake, M.

    1986-01-01

    Death certificates issued in Yokkaichi, Japan, during the 21 yr from 1963 until 1983 were surveyed to determine the relationship between changes in air pollution and mortality due to bronchial asthma and chronic bronchitis. The following results were obtained. In response to worsening air pollution, mortality for bronchial asthma and chronic bronchitis began to increase. Mortality due to bronchial asthma decreased immediately in response to improvement of pollution, whereas mortality due to chronic bronchitis decreased to the level in the control area 4 to 5 yr after the concentration of sulfur dioxide (SO/sub 2/) began to satisfy the ambient air quality standard. In the polluted area, mortality due to bronchial asthma in subjects who were 20 yr of age was higher during the period in which higher concentrations of sulfur oxides were prevalent.

  19. Estimating the flexibility of utility resource plans: An application to natural gas cofiring for SO[sub 2] control

    SciTech Connect

    Hobbs, B.F. ); Honious, J.C. ); Bluestein, J. )

    1994-02-01

    Utility planners must cope with large uncertainties concerning fuel prices, environmental laws, power demands, and the cost and availability of new resources. In this situation, flexibility is valuable. A flexible plan is one that enables the utility to quickly and inexpensively change the system's configuration or operation in response to varying market and regulatory conditions. The authors present a decision tree-based method for quantifying the economic value of flexibility. The method is then used to compare the relative flexibility of natural gas cofiring with other strategies to comply with the acid rain control requirements of the 1990 US Clean Air Act Amendments. The authors also compare the measure of flexibility with one based on the standard deviation of present worth. The latter perversely finds the least flexible technology (scrubbing) to be the most flexible''.

  20. Recovery of concentrated H/sub 2/S from SO/sub 2/ contained in flue gas

    SciTech Connect

    Miller, R.

    1986-05-13

    The process consists of: (a) contacting the gas with a recycled, aqueous, alkaline reaction medium being supplied from the separated solution obtained in step (d); (b) adding, in the substantial absence of air, sufficient sodium carbonate formed in step (g) to the reaction medium formed in step (a) to react with the dissolved sodium pyrosulfite to form a slurry of solid sodium sulfite suspended in the resulting aqueous, alkaline reaction medium and concentrated, gaseous carbon dioxide; (c) separating the concentrated, gaseous carbon dioxide and recycling it to step (i); (d) separating solid sodium sulfite from the aqueous, alkaline reaction medium and recycling the reaction medium to step (a); (e) reducing the separated sodium sulfite to sodium sulfide; (f) mixing the sodium sulfide formed in step (e) with water; (g) reacting, in the substantial absence of air, the sodium sulfide contained in the mixture formed in step (f) with particles of solid sodium bicarbonate from step (j) at a temperature sufficiently high to form a slurry of solid sodium carbonate suspended in a saturated sodium carbonate solution and a gas mixture consisting primarily of water vapor and hydrogen sulfide and recovering the hydrogen sulfide; (h) recycling part of the solid sodium carbonate formed in step (g) to step (b); (i) adding the remainder of the sodium carbonate formed in step (g) to a saturated sodium bicarbonate solution and carbonating the resulting mixture with carbon dioxide formed in step (b) to form a slurry of solid particles of sodium bicarbonate dispersed in the solution; and (j) separating particles of sodium bicarbonate from the slurry formed in step (i) and recycling the separated particles to step (g).

  1. Volcanic gas emissions and their effect on ambient air character

    SciTech Connect

    Sutton, A.J.; Elias, T.

    1994-01-01

    This bibliography was assembled to service an agreement between Department of Energy and the USGS to provide a body of references and useful annotations for understanding background gas emissions from Kilauea volcano. The current East Rift Zone (ERZ) eruption of Kilauea releases as much as 500,000 metric tonnes of SO{sub 2} annually, along with lesser amounts of other chemically and radiatively active species including H{sub 2}S, HCl, and HF. Primary degassing locations on Kilauea are located in the summit caldera and along the middle ERZ. The effects of these emissions on ambient air character are a complex function of chemical reactivity, source geometry and effusivity, and local meteorology. Because of this complexity, we organized the bibliography into three main sections: (1) characterizing gases as they leave the edifice; (2) characterizing gases and chemical reaction products away from degassing sources; and (3) Hawaii Island meteorology.

  2. Flue gas desulfurization/denitrification using metal-chelate additives

    DOEpatents

    Harkness, John B. L.; Doctor, Richard D.; Wingender, Ronald J.

    1986-01-01

    A method of simultaneously removing SO.sub.2 and NO from oxygen-containing flue gases resulting from the combustion of carbonaceous material by contacting the flue gas with an aqueous scrubber solution containing an aqueous sulfur dioxide sorbent and an active metal chelating agent which promotes a reaction between dissolved SO.sub.2 and dissolved NO to form hydroxylamine N-sulfonates. The hydroxylamine sulfonates are then separated from the scrubber solution which is recycled.

  3. Flue gas desulfurization/denitrification using metal-chelate additives

    DOEpatents

    Harkness, J.B.L.; Doctor, R.D.; Wingender, R.J.

    1985-08-05

    A method of simultaneously removing SO/sub 2/ and NO from oxygen-containing flue gases resulting from the combustion of carbonaceous material by contacting the flue gas with an aqueous scrubber solution containing an aqueous sulfur dioxide sorbent and an active metal chelating agent which promotes a reaction between dissolved SO/sub 2/ and dissolved NO to form hydroxylamine N-sulfonates. The hydroxylamine sulfonates are then separated from the scrubber solution which is recycled. 3 figs.

  4. Microbial reduction of SO{sub 2} and NO{sub x} as a means of by- product recovery/disposal from regenerable processes for the desulfurization of flue gas. Technical progress report, June 11, 1992--September 11, 1992

    SciTech Connect

    Sublette, K.L.

    1992-12-31

    Based on the work described simultaneous SO{sub 2}/No{sub x} removal from flue gas based on direct contact of the gas with SRB and T. denitrificans co-cultures or cultures-in-series has been eliminated as a viable process concept at this time. The technical reasons are as follows: (1) NO inhibition of SO{sub 2} reduction by D. desulfuricans - Although the NO concentrations used in the experiments described above are somewhat higher than that found in a typical flue gas, it is quite possible that at lower NO concentrations (or partial pressures) the inhibiting effects will simply take longer to become apparent. (2) Nitrate suppression of NO removal - As noted previously, the cultivation of T. denitrificans in a microbial flue gas treatment system (either one or two stages) would require sulfide-limiting conditions. Therefore, the electron acceptor must be in excess, requiring nitrate in the T. denitrificans process culture. As shown in experiments described above, nitrate significantly suppresses the removal of NO from a feed gas making simultaneous SO{sub 2}/NO{sub x} removal impractical by microbial means. (3) O{sub 2} inhibition of SO{sub 2} and NO reduction - It has been demonstrated that D. desulfuricans working cultures are tolerant of up to 1.7% O{sub 2} in the feed gas. However, further increases in the O{sub 2} partial pressure in the feed gas resulted in O{sub 2} inhibition of SO{sub 2} reduction. These inhibiting levels of O{sub 2} are comparable to those concentrations found in flue gases (3). Therefore, in any process in which raw flue gas contacts a D. desulfuricans culture marginal stability at best can be expected.

  5. Microbial reduction of SO[sub 2] and NO[sub x] as a means of by- product recovery/disposal from regenerable processes for the desulfurization of flue gas

    SciTech Connect

    Sublette, K.L.

    1992-01-01

    Based on the work described simultaneous SO[sub 2]/No[sub x] removal from flue gas based on direct contact of the gas with SRB and T. denitrificans co-cultures or cultures-in-series has been eliminated as a viable process concept at this time. The technical reasons are as follows: (1) NO inhibition of SO[sub 2] reduction by D. desulfuricans - Although the NO concentrations used in the experiments described above are somewhat higher than that found in a typical flue gas, it is quite possible that at lower NO concentrations (or partial pressures) the inhibiting effects will simply take longer to become apparent. (2) Nitrate suppression of NO removal - As noted previously, the cultivation of T. denitrificans in a microbial flue gas treatment system (either one or two stages) would require sulfide-limiting conditions. Therefore, the electron acceptor must be in excess, requiring nitrate in the T. denitrificans process culture. As shown in experiments described above, nitrate significantly suppresses the removal of NO from a feed gas making simultaneous SO[sub 2]/NO[sub x] removal impractical by microbial means. (3) O[sub 2] inhibition of SO[sub 2] and NO reduction - It has been demonstrated that D. desulfuricans working cultures are tolerant of up to 1.7% O[sub 2] in the feed gas. However, further increases in the O[sub 2] partial pressure in the feed gas resulted in O[sub 2] inhibition of SO[sub 2] reduction. These inhibiting levels of O[sub 2] are comparable to those concentrations found in flue gases (3). Therefore, in any process in which raw flue gas contacts a D. desulfuricans culture marginal stability at best can be expected.

  6. Climate change and air quality: international perspectives and policy implications

    SciTech Connect

    Ronald Prinn; Stephen Dorling

    2005-10-01

    Three major air quality relevant atmospheric constituents that also influence the climate are methane, ozone, and aerosols. Their respective atmospheric lifetimes are roughly 10 years, several days (near surface) to a month (in the free troposphere), and a week. Both O{sub 3} and aerosols are important regional air pollutants in the troposphere. All three constituents also influence the radiative budget of the atmosphere. With the exception of black carbon (BC) aerosols reflect radiation and have a net cooling effect. BC, absorbs solar radiation and warms the atmosphere locally, setting off a readjustment of heat, momentum, clouds, and precipitation patterns that are at least regional in scale. They all have clear international relevance. Interactions between air quality and climate change are highly complex. The Prinn 7 calculations suggest that air pollution policies may have only a small influence, either positive or negative, on global-scale climate change. However, even small militations of climate change can be disproportionately important in economic terms. This occurs because the highest cost climate change mitigation measures, those occurring at the margin, may be avoided. More policy-relevant research needs to be undertaken. This research should include studies of (1) the effects of air pollution policy on overall demand for fossil fuels and individual demands for coal, oil, and gas; (2) the effects of caps on BC (as a regulated air pollutant) on climate; and (3) the effects on ecosystems of changes in deposition rates of acids, nitrates, and sulfates and levels of exposure to SO{sub 2} and NO{sub 2} resulting from air pollution reductions. This article is one of a set of six in this issue of EM devoted to understanding the interactions between climate change and air quality. 12 refs., 1 fig.

  7. Health effects of air pollution due to coal combustion in the Chestnut Ridge region of Pennsylvania: cross-section survey of children

    SciTech Connect

    Schenker, M.B.; Vedal, S.; Batterman, S.; Samet, J.; Speizer, F.E.

    1986-03-01

    A cross-sectional study of 4071 children aged 6-11 yr of age from a rural region of Western Pennsylvania was conducted in spring of 1979. Standardized children's questionnaires were distributed to the parents and returned by the children to school, where spirometry was performed. The region was divided into low-, moderate-, and high-pollution areas on the basis of the 1974-1978, 3-hr, 24-hr, and annual averages for sulfur dioxide (SO/sub 2/). Seventeen monitoring stations in the region and a triangulation procedure were used to estimate centroid levels in each geographic residence area. After adjusting the respiratory symptom response outcomes and the pulmonary function levels for known predictors, no significant association was noted for level of SO/sub 2/. However, the highest exposure categories were only slightly above the present annual and 24-hr National Air Quality Standards for SO/sub 2/. We conclude that at levels of exposure to which these children were exposed, only by study of potentially sensitive subsets or measures of acute response would it be possible to detect respiratory outcomes associated with ambient air pollution.

  8. Additive Manufacturing Infrared Inspection

    NASA Technical Reports Server (NTRS)

    Gaddy, Darrell

    2014-01-01

    Additive manufacturing is a rapid prototyping technology that allows parts to be built in a series of thin layers from plastic, ceramics, and metallics. Metallic additive manufacturing is an emerging form of rapid prototyping that allows complex structures to be built using various metallic powders. Significant time and cost savings have also been observed using the metallic additive manufacturing compared with traditional techniques. Development of the metallic additive manufacturing technology has advanced significantly over the last decade, although many of the techniques to inspect parts made from these processes have not advanced significantly or have limitations. Several external geometry inspection techniques exist such as Coordinate Measurement Machines (CMM), Laser Scanners, Structured Light Scanning Systems, or even traditional calipers and gages. All of the aforementioned techniques are limited to external geometry and contours or must use a contact probe to inspect limited internal dimensions. This presentation will document the development of a process for real-time dimensional inspection technique and digital quality record of the additive manufacturing process using Infrared camera imaging and processing techniques.

  9. [Air pollution].

    PubMed

    Bauters, Christophe; Bauters, Gautier

    2016-01-01

    Short-term exposure to particulate matter (PM) air pollution is associated with an increased cardiovascular mortality. Chronic exposure to PM is also associated with cardiovascular risk. Myocardial infarction and heart failure are the most common cardiovascular events associated with PM pollution. The pathophysiological mechanisms related to PM pollution are inflammation, thrombosis, vasomotion abnormalities, progression of atherosclerosis, increased blood pressure, and cardiac remodeling. A decrease in PM exposure may be particularly beneficial in subjects with a high cardiovascular risk. PMID:26547674

  10. Phenylethynyl Containing Reactive Additives

    NASA Technical Reports Server (NTRS)

    Connell, John W. (Inventor); Smith, Joseph G., Jr. (Inventor); Hergenrother, Paul M. (Inventor)

    2002-01-01

    Phenylethynyl containing reactive additives were prepared from aromatic diamine, containing phenylethvnvl groups and various ratios of phthalic anhydride and 4-phenylethynviphthalic anhydride in glacial acetic acid to form the imide in one step or in N-methyl-2-pvrrolidinone to form the amide acid intermediate. The reactive additives were mixed in various amounts (10% to 90%) with oligomers containing either terminal or pendent phenylethynyl groups (or both) to reduce the melt viscosity and thereby enhance processability. Upon thermal cure, the additives react and become chemically incorporated into the matrix and effect an increase in crosslink density relative to that of the host resin. This resultant increase in crosslink density has advantageous consequences on the cured resin properties such as higher glass transition temperature and higher modulus as compared to that of the host resin.

  11. Air filtering device

    SciTech Connect

    Backus, A.L.

    1992-07-28

    This patent describes a room air cleaning device. It comprises: a box housing having an air inlet and an air outlet provided therein; a vertical baffle coupled to the box housing opposite the air outlet and spaced form the box housing such that an air egress outlet is formed between the vertical baffle and the box housing; air cleansing means substantially disposed within the box housing and cleansing air passing into the inlet and out of the air egress outlet; a fan disposed within the box housing, the fan providing air movement through the air inlet and the air egress outlet; wherein air exits the room air cleaning device through the air egress outlet as a vertical plane of moving air; and wherein formation of the vertical plane of moving air contributes to the formation of a low pressure area drawing impure air toward the air inlet.

  12. Aerodynamical sealing by air curtains

    NASA Astrophysics Data System (ADS)

    Frank, Daria; Linden, Paul

    2015-11-01

    Air curtains are artificial high-velocity plane turbulent jets which are installed in a doorway in order to reduce the heat and the mass exchange between two environments. The performance of an air curtain is assessed in terms of the sealing effectiveness E, the fraction of the exchange flow prevented by the air curtain compared to the open-door situation. The main controlling parameter for air curtain dynamics is the deflection modulus Dm representing the ratio of the momentum flux of the air curtain and the transverse forces acting on it due to the stack effect. In this talk, we examine the influence of two factors on the performance of an air curtain: the presence of an additional ventilation pathway in the room, such as a small top opening, and the effects of an opposing buoyancy force which for example arises if a downwards blowing air curtain is heated. Small-scale experiments were conducted to investigate the E (Dm) -curve of an air curtain in both situations. We present both experimental results and theoretical explanations for our observations. We also briefly illustrate how simplified models developed for air curtains can be used for more complex phenomena such as the effects of wind blowing around a model building on the ventilation rates through the openings.

  13. Solubilities of Peroxyacetyl Nitrate and Peroxynitrate in Water and Aqueous H(sub 2)SO(sub 4)

    NASA Technical Reports Server (NTRS)

    Leu, M. T.; Zhang, R.

    1998-01-01

    In addition, the effective Henry's law constant and the associative enthalpy change of solvation of PNA in water are determined to be 39.95 mol kg^-1 atm^-1 and -69.84 kJ mol^-1 at 298.15K, respectively.

  14. Additives in plastics.

    PubMed Central

    Deanin, R D

    1975-01-01

    The polymers used in plastics are generally harmless. However, they are rarely used in pure form. In almost all commercial plastics, they are "compounded" with monomeric ingredients to improve their processing and end-use performance. In order of total volume used, these monomeric additives may be classified as follows: reinforcing fibers, fillers, and coupling agents; plasticizers; colorants; stabilizers (halogen stabilizers, antioxidants, ultraviolet absorbers, and biological preservatives); processing aids (lubricants, others, and flow controls); flame retardants, peroxides; and antistats. Some information is already available, and much more is needed, on potential toxicity and safe handling of these additives during processing and manufacture of plastics products. PMID:1175566

  15. Recent trends of energy consumption and air pollution in China

    SciTech Connect

    Tian, H.Z.; Hao, J.M.; Hu, M.Y.; Nie, Y.F.

    2007-03-15

    The relationship between air pollution and energy consumption is a hot topic that is receiving increased attention by industry, regulatory agencies, as well as the public. China is currently undergoing a profound economic and social transition. Since the late 1990s, China's energy production and consumption have undergone an unexpectedly precipitous up-and-down fluctuation, and the related air pollution has changed dramatically. In this study, energy use and the related air pollution during the past years are analyzed and discussed in detail. Further, suggestions on sustainable energy use, air pollution control, as well as CO{sub 2}, abatement are proposed. By 2003, the total primary energy consumption of China had reached 1678.00 million tons (MT) of standard coal equivalent. As a result, emissions of SO{sub 2}, and NOx increased to 21.58 and 16.13 MT in 2003, respectively. Acid rain pollution worsened nationwide after 2000, with the areas of acid rain remaining stable while some seriously acid rain polluted areas worsened. This implies that more rigorous regulations, standards, and effective economic policies are needed.

  16. Implications of air pollution effects on athletic performance

    SciTech Connect

    Pierson, W.E.; Covert, D.S.; Koenig, J.Q.; Namekata, T.; Kim, Y.S.

    1986-06-01

    Both controlled human studies and observational studies suggest that air pollution adversely affects athletic performance during both training and competition. The air pollution dosage during exercise is much higher than during rest because of a higher ventilatory rate and both nasal and oral breathing in the former case. For example, sulfur dioxide, which is a highly water-soluble gas, is almost entirely absorbed in the upper respiratory tract during nasal breathing. However, with oral pharyngeal breathing, the amount of sulfur dioxide that is absorbed is significantly less, and with exercise and oral pharyngeal breathing a significant decrease in upper airway absorption occurs, resulting in a significantly larger dosage of this pollutant being delivered to the tracheobronchial tree. Recently, several controlled human studies have shown that the combination of exercise and pollutant exposure (SO/sub 2/ or O/sub 3/) caused a marked bronchoconstriction and reduced ventilatory flow when compared to pollution exposure at rest. In a situation like the Olympic Games where milliseconds and millimeters often determine the success of athletes, air pollution can be an important factor in affecting their performance. This paper examines possible impacts of air pollution on athletic competition.

  17. Natural Flow Air Cooled Photovoltaics

    NASA Astrophysics Data System (ADS)

    Tanagnostopoulos, Y.; Themelis, P.

    2010-01-01

    Our experimental study aims to investigate the improvement in the electrical performance of a photovoltaic installation on buildings through cooling of the photovoltaic panels with natural air flow. Our experimental study aims to investigate the improvement in the electrical performance of a photovoltaic installation on buildings through cooling of the photovoltaic panels with natural air flow. We performed experiments using a prototype based on three silicon photovoltaic modules placed in series to simulate a typical sloping building roof with photovoltaic installation. In this system the air flows through a channel on the rear side of PV panels. The potential for increasing the heat exchange from the photovoltaic panel to the circulating air by the addition of a thin metal sheet (TMS) in the middle of air channel or metal fins (FIN) along the air duct was examined. The operation of the device was studied with the air duct closed tightly to avoid air circulation (CLOSED) and the air duct open (REF), with the thin metal sheet (TMS) and with metal fins (FIN). In each case the experiments were performed under sunlight and the operating parameters of the experimental device determining the electrical and thermal performance of the system were observed and recorded during a whole day and for several days. We collected the data and form PV panels from the comparative diagrams of the experimental results regarding the temperature of solar cells, the electrical efficiency of the installation, the temperature of the back wall of the air duct and the temperature difference in the entrance and exit of the air duct. The comparative results from the measurements determine the improvement in electrical performance of the photovoltaic cells because of the reduction of their temperature, which is achieved by the naturally circulating air.

  18. Biobased lubricant additives

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fully biobased lubricants are those formulated using all biobased ingredients, i.e. biobased base oils and biobased additives. Such formulations provide the maximum environmental, safety, and economic benefits expected from a biobased product. Currently, there are a number of biobased base oils that...

  19. Multifunctional fuel additives

    SciTech Connect

    Baillargeon, D.J.; Cardis, A.B.; Heck, D.B.

    1991-03-26

    This paper discusses a composition comprising a major amount of a liquid hydrocarbyl fuel and a minor low-temperature flow properties improving amount of an additive product of the reaction of a suitable diol and product of a benzophenone tetracarboxylic dianhydride and a long-chain hydrocarbyl aminoalcohol.

  20. Examination of utility Phase 1 compliance choices and state reactions to Title IV of the Clean Air Act Amendments of 1990

    SciTech Connect

    Bailey, K.A.; Elliott, T.J.; Carlson, L.J.; South, D.W.

    1993-11-01

    Title IV (acid rain) of the Clean Air Act Amendments of 1990 is imposing new limitations on the emission of sulfur dioxide (SO{sub 2}) and nitrogen oxides (N{sub x}) from electric power plants. The act requires utilities to develop compliance plans to reduce these emissions, and indications are that these plans will dramatically alter traditional operating procedures. A key provision of the SO{sub 2} control program deaned in Title IV is the creation of a system of emission allowances, with utilities having the option of complying by adjusting system emissions and allowance holdings. A compilation of SO{sub 2} compliance activities by the 110 utility plants affected by Phase I is summarized in this report. These compliance plans are presented in a tabular form, correlated with age, capacity, and power pool data. A large number of the Phase I units (46%) have chosen to blend or switch to lower sulfur coals. This choice primarily is in response to (1) prices of low-sulfur coal and (2) the need to maintain SO{sub 2} control flexibility because of uncertain future environmental regulations (e.g., air toxics, carbon dioxide) and compliance prices. The report also discusses the responses of state legislatures and public utility commissions to the compliance requirements in Title IV. Most states have taken negligible action regarding the regulatory treatment of allowances and compliance activities. To protect mine employment, states producing high-sulfur coal have enacted regulations encouraging continued use of that coal, but for the most part, this response has had little effect on utility compliance choices.

  1. Air weapon fatalities.

    PubMed Central

    Milroy, C M; Clark, J C; Carter, N; Rutty, G; Rooney, N

    1998-01-01

    AIMS: To describe characteristics of a series of people accidentally and deliberately killed by air powered weapons. METHODS: Five cases of fatal airgun injury were identified by forensic pathologists and histopathologists. The circumstances surrounding the case, radiological examination, and pathological findings are described. The weapon characteristics are also reported. RESULTS: Three of the victims were adult men, one was a 16 year old boy, and one an eight year old child. Four of the airguns were .22 air rifles, the other a .177 air rifle. Two committed suicide, one person shooting himself in the head, the other in the chest. In both cases the guns were fired at contact range. Three of the cases were classified as accidents: in two the pellet penetrated into the head and in one the chest. CONCLUSIONS: One person each year dies from an air powered weapon injury in the United Kingdom. In addition there is considerable morbidity from airgun injuries. Fatalities and injuries are most commonly accidents, but deliberately inflicted injuries occur. Airguns are dangerous weapons when inappropriately handled and should not be considered as toys. Children should not play with airguns unsupervised. Images PMID:9797730

  2. Boron addition to alloys

    SciTech Connect

    Coad, B. C.

    1985-08-20

    A process for addition of boron to an alloy which involves forming a melt of the alloy and a reactive metal, selected from the group consisting of aluminum, titanium, zirconium and mixtures thereof to the melt, maintaining the resulting reactive mixture in the molten state and reacting the boric oxide with the reactive metal to convert at least a portion of the boric oxide to boron which dissolves in the resulting melt, and to convert at least portion of the reactive metal to the reactive metal oxide, which oxide remains with the resulting melt, and pouring the resulting melt into a gas stream to form a first atomized powder which is subsequently remelted with further addition of boric oxide, re-atomized, and thus reprocessed to convert essentially all the reactive metal to metal oxide to produce a powdered alloy containing specified amounts of boron.

  3. Tackifier for addition polyimides

    NASA Technical Reports Server (NTRS)

    Butler, J. M.; St.clair, T. L.

    1980-01-01

    A modification to the addition polyimide, LaRC-160, was prepared to improve tack and drape and increase prepeg out-time. The essentially solventless, high viscosity laminating resin is synthesized from low cost liquid monomers. The modified version takes advantage of a reactive, liquid plasticizer which is used in place of solvent and helps solve a major problem of maintaining good prepeg tack and drape, or the ability of the prepeg to adhere to adjacent plies and conform to a desired shape during the lay up process. This alternate solventless approach allows both longer life of the polymer prepeg and the processing of low void laminates. This approach appears to be applicable to all addition polyimide systems.

  4. [Biologically active food additives].

    PubMed

    Velichko, M A; Shevchenko, V P

    1998-07-01

    More than half out of 40 projects for the medical science development by the year of 2000 have been connected with the bio-active edible additives that are called "the food of XXI century", non-pharmacological means for many diseases. Most of these additives--nutricevtics and parapharmacevtics--are intended for the enrichment of food rations for the sick or healthy people. The ecologicaly safest and most effective are combined domestic adaptogens with immuno-modulating and antioxidating action that give anabolic and stimulating effect,--"leveton", "phytoton" and "adapton". The MKTs-229 tablets are residue discharge means. For atherosclerosis and general adiposis they recommend "tsar tablets" and "aiconol (ikhtien)"--on the base of cod-liver oil or "splat" made out of seaweed (algae). All these preparations have been clinically tested and received hygiene certificates from the Institute of Dietology of the Russian Academy of Medical Science. PMID:9752776

  5. Electrophilic addition of astatine

    SciTech Connect

    Norseev, Yu.V.; Vasaros, L.; Nhan, D.D.; Huan, N.K.

    1988-03-01

    It has been shown for the first time that astatine is capable of undergoing addition reactions to unsaturated hydrocarbons. A new compound of astatine, viz., ethylene astatohydrin, has been obtained, and its retention numbers of squalane, Apiezon, and tricresyl phosphate have been found. The influence of various factors on the formation of ethylene astatohydrin has been studied. It has been concluded on the basis of the results obtained that the univalent cations of astatine in an acidic medium is protonated hypoastatous acid.

  6. Hydrocarbon fuel additive

    SciTech Connect

    Ambrogio, S.

    1989-02-28

    This patent describes the method of fuel storage or combustion, wherein the fuel supply contains small amounts of water, the step of adding to the fuel supply an additive comprising a blend of a hydrophilic agent chosen from the group of ethylene glycol, n-butyl alcohol, and cellosolve in the range of 22-37% by weight; ethoxylated nonylphenol in the range of 26-35% by weight; nonylphenol polyethylene glycol ether in the range of 32-43% by weight.

  7. Functional Generalized Additive Models.

    PubMed

    McLean, Mathew W; Hooker, Giles; Staicu, Ana-Maria; Scheipl, Fabian; Ruppert, David

    2014-01-01

    We introduce the functional generalized additive model (FGAM), a novel regression model for association studies between a scalar response and a functional predictor. We model the link-transformed mean response as the integral with respect to t of F{X(t), t} where F(·,·) is an unknown regression function and X(t) is a functional covariate. Rather than having an additive model in a finite number of principal components as in Müller and Yao (2008), our model incorporates the functional predictor directly and thus our model can be viewed as the natural functional extension of generalized additive models. We estimate F(·,·) using tensor-product B-splines with roughness penalties. A pointwise quantile transformation of the functional predictor is also considered to ensure each tensor-product B-spline has observed data on its support. The methods are evaluated using simulated data and their predictive performance is compared with other competing scalar-on-function regression alternatives. We illustrate the usefulness of our approach through an application to brain tractography, where X(t) is a signal from diffusion tensor imaging at position, t, along a tract in the brain. In one example, the response is disease-status (case or control) and in a second example, it is the score on a cognitive test. R code for performing the simulations and fitting the FGAM can be found in supplemental materials available online. PMID:24729671

  8. Nanocrystalline Ba{sub 0.97}Ca{sub 0.03}SO{sub 4}:Eu for ion beams dosimetry

    SciTech Connect

    Lochab, S. P.; Kanjilal, D.; Salah, Numan; Habib, Sami S.; Lochab, Jyoti; Ranjan, Ranju; Aleynikov, V. E.; Rupasov, A. A.; Pandey, A.

    2008-08-01

    Nanoparticles of Ba{sub 0.97}Ca{sub 0.03}SO{sub 4}:Eu have been irradiated by 48 MeV Li{sup 3+}, 75 MeV C{sup 6+}, and 90 MeV O{sup 7+} ion beams with a fluence range of 1x10{sup 9}-1x10{sup 13} ion/cm{sup 2}. The thermoluminescence (TL) glow curves along with the response curves of this nanophosphor have been investigated and compared with those of the corresponding microcrystalline samples. TL glow curve of the nanophosphor exposed to {gamma}-rays has also been included in the letter with the aim of reporting some of the comparative measurements. The glow curves of the ion-beam irradiated nanomaterials are similar in their shapes to those induced by gamma rays, with a shift in the peak positions to the higher temperature side by around 30 K. The TL intensity of the ion-beam irradiated nanomaterials is found to decrease, while going from low to high atomic number (Z) ions (i.e., Li{sup 3+}{yields}O{sup 7+}). Similar trend was also observed in the linearity of the TL response curves. The response curve of Li ion irradiated nanomaterials is sublinear in the whole range of studied fluences. C ion has also a more or less similar response, while the O ion has a sublinear response over a shorter range of 1x10{sup 9}-1x10{sup 12} ion/cm{sup 2}, and above this range the response saturates. These results for the nanomaterials are much better than that of the corresponding microcrystalline sample irradiated by Li{sup 3+} ions. The curve was sublinear up to the fluence 1x10{sup 10} ion/cm{sup 2} and then saturates at higher fluences. The wider sublinear TL response of the nanocrystalline Ba{sub 0.97}Ca{sub 0.03}SO{sub 4}:Eu makes it superior to its corresponding microform and thus makes it a suitable candidate as a dosimeter to be used for detecting the doses of ions, especially the Li and C ions for their application in cancer radiotherapy and radiation biology.

  9. Nitrogen oxide abatement by distributed fuel addition

    SciTech Connect

    Wendt, J.O.L.; Meraab, J.

    1988-06-27

    This research is directed towards the development of engineering guidelines that define the application of distributed fuel addition as a technique for NOx abatement. It is expected that multiple fuel and air addition in the post-flame of a combustion process will increase free radical concentrations which destroy nitrogenous species and thus help them decay toward their equilibrium concentrations, which can be very low in that region of the combustor. Screening experiments were conducted on a laboratory scale downfired combustor. The objective was to compare NOx emissions arising from various combustion configurations, including fuel and/or air staging. Although the primary focus of this research is on NO control, a secondary effort was directed towards the measurement of N2O emissions from various coal combustion processes. N2O has been identified as a trace gas responsible for stratospheric ozone depletion, and has been hypothesized to arise from combustion processes, in amounts roughly proportional to NO emissions. Results presented in this report showed that the ratio N2O/NO was far from constant. The introduction of secondary air into a combustion process was accompanied an increase in N2O emissions. The measured N2O was always less than 10 ppm even under the most favorable combustion conditions. Reburning with premixed fuel and air mixtures was not effective in reducing NO emissions.

  10. Clean Air Status and Trends Network (CASTNET) deposition, summary report (1987--1995). Technical report

    SciTech Connect

    Baumgardner, R.

    1998-07-01

    The National Dry Deposition Network (NDDN) was established in 1986 to provide long term estimates of dry deposition across the continental United States. In 1990, NDDN was incorporated into the Clean Air Status and Trends Network (CASTNET) which was created to address the requirements of the Clean Air Act Amendments (CAAA). Approximately 50 sites were operational from 1989 through 1995 with the majority of the sites located in rural eastern United States. Each site is equipped with sensors for continuous measurements of ozone and meteorological variables required for the estimation of dry deposition rates. Weekly average concentrations of particulate sulfate (SO{sub 4}), particulate nitrate (NO{sub 3{minus}}), particulate ammonium (NH{sub 4+}), sulfur dioxide (SO{sub 2}), and nitric acid (HNO{sub 3}) were measured at all sites. Precipitation samples were collected at selected sites and analyzed for acidity and related species in order to estimate wet deposition. Under the CASTNET program, a visibility monitoring network and a Mountain Acid Deposition Program (MADPro) were established. This report summaries the analysis and interpretation of NDDN and CASTNET measurements taken from 1987 through 1995. The extensive database of concentrations and calculated dry, wet, and total depositions have been analyzed.

  11. Effects of the 1990 Clean Air Act amendments on distributions of visual impairment

    SciTech Connect

    Shannon, J.D.; Camp, J.; Trexler, E.C. Jr.

    1996-02-01

    The Acid Rain Provisions (Title IV) of the 1990 Clean Air Act Amendments (1990 CAAA) focus on emission policies designed to reduce the amount of deposition of acidifying pollutants, particularly in the Northeast. The primary strategy is a significant reduction in SO{sub 2} emissions, with lesser reductions scheduled for NO{sub {times}} emissions. However, lessening of acid deposition is not the only important benefit of the emission control strategy. Decreasing SO{sup {minus}} and NO {sup {minus}} emissions will decrease atmospheric concentrations of sulfate and nitrate particles, which account for much of the visibility reduction associated with regional haze. Although one can get a qualitative sense of how visibility might improve by examining historical large-scale trends in regional emission totals and regional visibility, quantification of the expected improvement requires model simulations. One must model the spatial and temporal patterns of emissions reductions; the relevant pollutant transport, transformation, and removal processes in the atmosphere; and the changes in particulate loading. For this initial examination of the visibility improvement at Shenandoah National Park associated the the Phase I and Phase II SO{sub 2} emission reductions, we have linked emission trend projections taken from ongoing analysis of the 1990 CAAA at Argonne National Laboratory, regional transport modeling with the Advanced Statistical Trajectory Regional Air Pollution (ASTRAP) model and visual impairment modeling with the Visibility Assessment Scoping Model (VASM).

  12. AIRS Level 2 Data Products

    NASA Technical Reports Server (NTRS)

    Vicente, Gilberto

    2003-01-01

    The Atmospheric InfraRed Sounder (AIRS) Standard Retrieval Product consists of retrieved cloud and surface properties; profiles of retrieved temperature, water vapor, and ozone; and a flag indicating the presence of cloud ice or water. They contain quality assessment flags in addition to retrieved quantities and are generated for all locations where atmospheric soundings are taken. An AIRS granule consists of 6 minutes of data. This corresponds to approximately 1/15 of an orbit but exactly 45 scan lines of AMSU-A data or 135 scan lines of AIRS and HSB data.

  13. Effects of instrument precision and spatial variability on the assessment of the temporal variation of ambient air pollution in Atlanta, Georgia

    SciTech Connect

    Katherine S. Wade; James A. Mulholland; Amit Marmur; Armistead G. Russell; Ben Hartsell; Eric Edgerton; Mitch Klein; Lance Waller; Jennifer L. Peel; Paige E. Tolbert

    2006-06-15

    Data from the U.S. Environmental Protection Agency Air Quality System, the Southeastern Aerosol Research and Characterization database, and the Assessment of Spatial Aerosol Composition in Atlanta database for 1999 through 2002 have been used to characterize error associated with instrument precision and spatial variability on the assessment of the temporal variation of ambient air pollution in Atlanta, GA. These data are being used in time series epidemiologic studies in which associations of acute respiratory and cardiovascular health outcomes and daily ambient air pollutant levels are assessed. Modified semivariograms are used to quantify the effects of instrument precision and spatial variability on the assessment of daily metrics of ambient gaseous pollutants (SO{sub 2}, CO, NOx, and O{sub 3}) and fine particulate matter (PM2.5) (PM2.5 mass, sulfate, nitrate, ammonium, elemental carbon (EC), and organic carbon (OC)). Variation because of instrument imprecision represented 7-40% of the temporal variation in the daily pollutant measures and was largest for the PM2.5 EC and OC. Spatial variability was greatest for primary pollutants (SO{sub 2}, CO, NOx, and EC). Population-weighted variation in daily ambient air pollutant levels because of both instrument imprecision and spatial variability ranged from 20% of the temporal variation for O{sub 3} to 70% of the temporal variation for SO{sub 2} and EC. Wind rose plots, corrected for diurnal and seasonal pattern effects, are used to demonstrate the impacts of local sources on monitoring station data. The results presented are being used to quantify the impacts of instrument precision and spatial variability on the assessment of health effects of ambient air pollution in Atlanta and are relevant to the interpretation of results from time series health studies that use data from fixed monitors. 38 refs., 8 figs., 4 tabs.

  14. Commercial demonstration of the NOXSO SO{sub 2}/NO{sub x} removal flue gas cleanup system. Quarterly technical progress report No. 16, December 1, 1994--February 28, 1995

    SciTech Connect

    1995-12-31

    The NOXSO process is a dry, post-combustion flue gas treatment technology which uses a regenerable sorbent to simultaneously adsorb sulfur dioxide (SO{sub 2}) and nitrogen oxides (NO{sub x}) from flue gas. In the process, the SO{sub 2} is converted to a sulfur by- product (elemental sulfur, sulfuric acid, or liquid SO{sub 2}) and the NO{sub x} is converted to nitrogen and oxygen. The objective of the NOXSO Clean Coal Project is to design, construct, and operate a flue gas treatment system utilizing the NOXSO process at Alcoa Generating Corporation`s (AGC) Warrick Power Plant. The NOXSO plant is being designed to remove 98% of the SO{sub 2} and 75% of the NO{sub x} from the flue gas from the 150-MW equivalent, unit 2 boiler. The by-product to be generated by the project is liquid SO{sub 2}. Sufficient construction cost and operating data will be obtained during the project to confirm the process economics and provide a basis to guarantee performance on a commercial scale. The project is in the Front End Engineering/Environmental Evaluation Phase. Engineering activities are approximately 20% complete and activities to update the project estimate based on completed engineering and equipment bids have been initiated. Process study activities include laboratory fluid-bed adsorber studies, regenerator computer model development and studies, fluid-flow modelling in fluid-bed vessels, and evaluations of SO{sub 2} production processes. The laboratory- scale, fluid-bed adsorber studies are being conducted to improve the accuracy of the removal efficiency predictions and study the impact of adding a third adsorber stage. The construction of the steel, multi-stage reactor is currently underway. The regenerator computer model was revised and is being used to study design options for improving the regenerator performance. Fluid-flow modelling has been conducted to study the effect of grid supports on the gas flow inside the fluid bed vessels.

  15. Siloxane containing addition polyimides

    NASA Technical Reports Server (NTRS)

    Maudgal, S.; St. Clair, T. L.

    1984-01-01

    Addition polyimide oligomers have been synthesized from bis(gamma-aminopropyl) tetramethyldisiloxane and 3, 3', 4, 4'-benzophenonetetracarboxylic dianhydride using a variety of latent crosslinking groups as endcappers. The prepolymers were isolated and characterized for solubility (in amide, chlorinated and ether solvents), melt flow and cure properties. The most promising systems, maleimide and acetylene terminated prepolymers, were selected for detailed study. Graphite cloth reinforced composites were prepared and properties compared with those of graphite/Kerimid 601, a commercially available bismaleimide. Mixtures of the maleimide terminated system with Kerimid 601, in varying proportions, were also studied.

  16. Oil additive process

    SciTech Connect

    Bishop, H.

    1988-10-18

    This patent describes a method of making an additive comprising: (a) adding 2 parts by volume of 3% sodium hypochlorite to 45 parts by volume of diesel oil fuel to form a sulphur free fuel, (b) removing all water and foreign matter formed by the sodium hypochlorite, (c) blending 30 parts by volume of 24% lead naphthanate with 15 parts by volume of the sulphur free fuel, 15 parts by volume of light-weight material oil to form a blended mixture, and (d) heating the blended mixture slowly and uniformly to 152F.

  17. 2. Southeast side of addition. View to northwest. Offutt ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Southeast side of addition. View to northwest. - Offutt Air Force Base, Looking Glass Airborne Command Post, Aerospace Ground Equipment (AGE) Storage Facility, Far Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  18. 5. General interior overview of addition. View to south. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. General interior overview of addition. View to south. - Offutt Air Force Base, Looking Glass Airborne Command Post, Aerospace Ground Equipment (AGE) Storage Facility, Far Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  19. 6. General interior overview of addition. View to northwest. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. General interior overview of addition. View to northwest. - Offutt Air Force Base, Looking Glass Airborne Command Post, Aerospace Ground Equipment (AGE) Storage Facility, Far Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  20. 3. Northwest side and southwest rear of addition. View to ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Northwest side and southwest rear of addition. View to east. - Offutt Air Force Base, Looking Glass Airborne Command Post, Aerospace Ground Equipment (AGE) Storage Facility, Far Northwest end of Project Looking Glass Historic District, Bellevue, Sarpy County, NE

  1. Interior view of addition pharmacy showing dutch door and security ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Interior view of addition pharmacy showing dutch door and security ceiling grate, facing north. - Albrook Air Force Station, Dispensary, East side of Canfield Avenue, Balboa, Former Panama Canal Zone, CZ

  2. Fouling control in seawater by on-line acid addition

    SciTech Connect

    Salvago, G.; Taccani, G.; Polimeni, R.; Fumagalli, G.; Picenoni, D.

    1996-11-01

    An experimental plant was set up containing once-through test lines supplied with seawater. The pH level of the seawater was maintained at 6.3 by the acids addition. Heat exchange monitoring equipment and channels exposing different metal specimens were installed on each of the lines. Observation by microscope and EDS analyses were carried out both on the specimen surfaces and on the cross section of the fouling after fracturing in liquid N{sub 2}. The results obtained show that: fouling must not be confused with its effects or simply with its biological components; acidifying seawater can prevent the resistance to heat exchange from increasing without impeding its biological activity. Observation by microscope of the fouling cross sections showed that in untreated seawater the foulings on stainless steel were composed of a continuous compact layer, covered by disorderly clusters. These compact layers were found to contain high quantities of corrosion products of the metals. Elements typical of corrosion products of ferrous materials (Fe, Mn) were also found on Pt, copper alloys and plastic materials. The addition of HCl or H{sub 2}SO{sub 4} to the seawater, to bring it to pH 6.3, reduces the amount of fouling adhering to the surfaces, prevents the development of the continuous layer containing iron and prevents significant increases in heat exchange resistance. The addition of CO{sub 2} can encourage the development of incoherent fibrous material with high Si content and low Fe content which is of little impediment to heat exchange. The addition of lactic acid can encourage both the abnormal development of biomass and the formation of several, separate, layers on stainless steel surfaces.

  3. AIR CLEANING FOR ACCEPTABLE INDOOR AIR QUALITY

    EPA Science Inventory

    The paper discusses air cleaning for acceptable indoor air quality. ir cleaning has performed an important role in heating, ventilation, and air-conditioning systems for many years. raditionally, general ventilation air-filtration equipment has been used to protect cooling coils ...

  4. Use of aromatic salts for simultaneously removing SO.sub.2 and NO.sub.x pollutants from exhaust of a combustion system

    DOEpatents

    Levendis, Yiannis A.; Wise, Donald L.

    1994-10-04

    A method is disclosed for removing pollutants from the exhaust of combustion systems burning fuels containing substantial amounts of sulfur and nitrogen. An exemplary method of the invention involves the formation and reaction of a sorbent comprising calcium benzoate. The calcium benzoate is either dry-sprayed (in the form of a fine powder) or wet-sprayed in an aqueous solution in a high temperature environment such as a combustion chamber. The latter technique is feasible since calcium benzoate is a water-soluble form of calcium. When the dispersed particles of calcium benzoate are heated to a high temperature, the organic benzoate burns off and fine calcium oxide particles are formed. These particles are cenospheric (hollow) and have thin and highly porous walls, thus, affording optimum external and internal accessibility for reacting with toxic gaseous emissions such as SO.sub.2. Further, the combustion of the organic benzoate portion of the sorbent results in the conversion of NO.sub.x to N.sub.2.

  5. Fermiology of the organic superconductor {beta}''-(ET){sub 2}SF{sub 5}CH{sub 2}CF{sub 2}SO{sub 3}.

    SciTech Connect

    Wosnitza, J.

    1998-07-29

    We present a detailed Fermi-surface (FS) investigation of the quasi two-dimensional (2D) organic superconductor (T{sub c} {approx} 4.5 K) {beta}{double_prime}(ET){sub 2}SF{sub 5}CH{sub 2}CF{sub 2}SO{sub 3}. In line with previous investigations, de Haas-van Alphen measurements in pulsed fields up to 60 T show a single oscillation frequency, F{sub 0} = 200 T, which corresponds to a FS size of about 5% of the first Brillouin zone. Angular dependent magnetoresistance oscillations (AMROs) are utilized for the exact determination of the in-plane FS, which is found to be a strongly elongated ellipsoid with an axes ratio of about 1:9. Transport measurements in static fields up to 33 T show an unusual temperature dependence of the Shubnikov-de Haas (SdH) signal, i.e., a decrease of the SdH amplitude with decreasing temperature.

  6. An application of long-range transport models to a comparison of selected SO/sub 2/ emission-reduction strategies

    SciTech Connect

    Norris, W.B.; Gautney, L.L.; Koss, T.C.

    1985-01-01

    The purpose of this study is to compare six emission-reduction strategies: by the examples: (1) strategy to reduce total atmospheric loading of sulfur; (2) a strategy to reduce wet sulfate deposition in the Adirondacks; (3) an alternative strategy to reduce wet sulfate deposition in the Adirondacks; (4) a strategy to reduce wet sulfate deposition in the southern section of the Appalachian Mountains (a region also ecologically sensitive) (5) a strategy to reduce sulfur flux to southeastern Canada; and (6) a strategy that embodies the three goals of strategies (3) - (5). The application of these strategies will be limited to SO/sub 2/ emission control in the 31 easternmost States of the U.S. The study will be presented in two parts. First, the strategies are explained in detail. Then, on the basis of modeling results, the strategies are compared. In the appendix, a description will be given of the two long-range transport models used to quantify emission-impact relationships--Model T for wet deposition, and Model F (a variation of Model T) for sulfur flux. Also, the emission levels, meteorology, and other parameters used in these models will be specified.

  7. Hydrothermal self-assembly and supercapacitive behaviors of Co(II) ion-modified graphene aerogels in H{sub 2}SO{sub 4} electrolyte

    SciTech Connect

    Bao, Qi; Hui, K.N.; Hui, K.S.; Wang, Yi; Hong, Xiaoting

    2014-08-15

    Highlights: • 3D Co(II) ions modified graphene aerogels were prepared by one-step hydrothermal process. • The aerogel electrodes showed hybrid supercapacitor behaviors. • The aerogel electrodes exhibited high rate capability and long-term cycling stability. - Abstract: Reduced graphene oxide (r-GO) aerogels decorated with divalent cobalt ions were synthesized via a one-pot hydrothermal self-assembly route. The interaction of Co(II) ions with 3D r-GO aerogels was investigated by spectroscopic techniques, including Raman, attenuated total reflectance infrared, and X-ray photoelectron spectroscopies. The excellent electrochemical properties of the aerogels were confirmed by cyclic voltammetry, galvanostatic charge/discharge tests, and electrochemical impedance spectroscopy in an acid electrolyte (1 M H{sub 2}SO{sub 4}). The Co(II) ion-modified r-GO aerogels can be used as high-performance hybrid supercapacitor materials with a specific capacitance of 387.2 F g{sup –1} at 1 A g{sup –1} current density and a good cycling stability without capacity decay over 1000 cycles. The mechanical integrity enhancement of the hybrid r-GO aerogel framework and the improvement in its unique capacitive performance are attributed to the efficient interconnection produced by electro-active Co(II) ions.

  8. High temperature membranes for H{sub 2}S and SO{sub 2} separations. Quarterly progress report, October 1, 1992--December 31, 1992

    SciTech Connect

    Winnick, J.

    1992-12-31

    Successful removal of SO{sub x} from flue gas depends on the development of a membrane able to achieve a current density of 50 mA/cm{sup 2} at a total voltage of approximately 1V. Flooding of electrode has been identified as a problem, leading to increasing polarization over time. The resulting reduction of surface area also tends to limit the mass transfer flux, reducing the efficiency of the cell. To reduce flooding, new materials and techniques of manufacture will be investigated, in the attempt to produce a ceramic membrane of approximately 50% theoretical density. This membrane must have proper pore size distribution to ensure sufficient capillary force to prevent impregnated electrolyte from flooding electrodes, and subsequently drying the ceramic membrane. Various methods of matrix production were studied this quarter: tape casting, pressing and sintering, and slip casting. Each will be discussed in turn. Electrolyte introduction to the cell is a continuing problem. The development of a method is still being investigated. Ideally, the electrolyte would be introduced as powder with binder in a green body. This binder would burn away at temperatures of approximately 300{degrees}C, leaving pure electrolyte to melt and complete the ionic path necessary for the electrochemical cell. The electrolyte used this quarter was, exclusively, a 90 wt % K{sub 2}S{sub 2}O{sub 7}/10 wt % V{sub 2}O{sub 5} mixture.

  9. Studies of chemical reduction of Fe(III)*EDTA in an SO{sub 2}/NO{sub x} aqueous scrubber system

    SciTech Connect

    Li, W.; Keener, T.C.; Mendelsohn, M.; Harkness, J.B.L.; Livengood, C.D.

    1996-03-01

    Ferrous*EDTA has been found to be an effective scrubbing agent for nitric oxide gas. A major process problem is oxidation of the iron to the ferric species, leading to a significant decrease in NO{sub x}-removal capability. Argonne National Laboratory discovered a class of organic compounds that, when used with ferrous*EDTA in a sodium carbonate chemistry, could maintain high levels of NO{sub x} removal. However, those antioxidant/reducing agents (A/R) are not effective in a lime-based chemistry. In recent reports, it has been found that ascorbic acid and related compounds are capable of maintaining stable NO{sub x} removals of about 50% (compared with about 15% without the agent) in a lime-based FGD chemistry with Fe(II)*EDTA. It is believed that the improved performance of Fe(II)*EDTA is due to the catalytic action of ascorbate in the Fe(III)*EDTA reduction system, where Fe(III)*EDTA is reduced by ascorbate and oxidized ascorbate is then reduced back to the ascorbate by sulfite/bisulfite anions, which come from the dissolution of SO{sub 2} in the flue gas. In the present work, the kinetics of the reduction of ferric chelate by ascorbate and reduction of oxidized ascorbate by sulfite/bisulfite anions at a typical flue-gas scrubber-system operating temperature ({approximately}55 C) have been determined.

  10. {sup 33}S hyperfine interactions in H{sub 2}S and SO{sub 2} and revision of the sulfur nuclear magnetic shielding scale

    SciTech Connect

    Helgaker, Trygve; Gauss, Jürgen; Cazzoli, Gabriele Puzzarini, Cristina

    2013-12-28

    Using the Lamb-dip technique, the hyperfine structure in the rotational spectra of H{sub 2}{sup 33}S and {sup 33}SO{sub 2} has been resolved and the corresponding parameters—that is, the sulfur quadrupole-coupling and spin–rotation tensors—were determined. The experimental parameters are in good agreement with results from high-level coupled-cluster calculations, provided that up to quadruple excitations are considered in the cluster operator, sufficiently large basis sets are used, and vibrational corrections are accounted for. The {sup 33}S spin-rotation tensor for H{sub 2}S has been used to establish a new sulfur nuclear magnetic shielding scale, combining the paramagnetic part of the shielding as obtained from the spin–rotation tensor with a calculated value for the diamagnetic part as well as computed vibrational and temperature corrections. The value of 716(5) ppm obtained in this way for the sulfur shielding of H{sub 2}S is in good agreement with results from high-accuracy quantum-chemical calculations but leads to a shielding scale that is about 28 ppm lower than the one suggested previously in the literature, based on the {sup 33}S spin-rotation constant of OCS.

  11. Partially sulfated lime-fly ash sorbents activated by water or steam for SO{sub 2} removal at a medium temperature

    SciTech Connect

    Liming Shi; Xuchang Xu

    2005-12-01

    Laboratory experiments were conducted to investigate the reactivity of partially sulfated lime-fly ash sorbents activated by water or steam for SO{sub 2} removal. Sulfation tests were performed at 550{sup o}C using a fixed bed reactor under conditions simulating economizer zone injection flue gas desulfurization. Activation experiments were conducted with water or steam using a range of temperatures between 100 and 550{sup o}C. The results showed that the reactivity of the sorbents was closely related to the content of Ca(OH){sub 2} formed in the activation process, which varied with the water or steam temperature. The sulfur dioxide capture capacity of Ca(OH){sub 2} in the sorbent is higher than that of CaO at a medium temperature. Water or steam temperatures in the range of 100-200{sup o}C are favorable to the formation of Ca(OH){sub 2} from CaO. 15 refs., 8 figs., 2 tabs.

  12. Addition polyimide adhesives containing various end groups

    NASA Technical Reports Server (NTRS)

    Saint Clair, A. K.; Saint Clair, T. L.

    1982-01-01

    Addition polyimode oligomers have been synthesized from 3,3 prime, 4,4 prime-benzophenone tetracarboxylic acid dianhydride and 3,3 prime-methylenedianiline using a variety of latent crosslinking groups as end-caps. The nominal 1300 molecular weight imide prepolymers were isolated and characterized for solubility in amide, chlorinated and ether solvents, melt-flow and cure properties, glass transition temperature, and thermal stability on heating in an air atmosphere. Adhesive strengths of the polyimides were obtained both at ambient and elevated temperatures before and after aging at 232 C. Properties of the novel addition polyimides were compared to a known nadic end-capped adhesive, LARC-13.

  13. Parent's Guide to School Indoor Air Quality. Revised

    ERIC Educational Resources Information Center

    Healthy Schools Network, Inc., 2012

    2012-01-01

    Air pollution is air pollution, indoors or out. Good indoor air quality (IAQ) contributes to a favorable learning environment for students, protects health, and supports the productivity of school personnel. In schools in poor repair, leaky roofs and crumbling walls have caused additional indoor air quality problems, including contamination with…

  14. Sewage sludge additive

    NASA Technical Reports Server (NTRS)

    Kalvinskas, J. J.; Mueller, W. A.; Ingham, J. D. (Inventor)

    1980-01-01

    The additive is for a raw sewage treatment process of the type where settling tanks are used for the purpose of permitting the suspended matter in the raw sewage to be settled as well as to permit adsorption of the dissolved contaminants in the water of the sewage. The sludge, which settles down to the bottom of the settling tank is extracted, pyrolyzed and activated to form activated carbon and ash which is mixed with the sewage prior to its introduction into the settling tank. The sludge does not provide all of the activated carbon and ash required for adequate treatment of the raw sewage. It is necessary to add carbon to the process and instead of expensive commercial carbon, coal is used to provide the carbon supplement.

  15. Perspectives on Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Bourell, David L.

    2016-07-01

    Additive manufacturing (AM) has skyrocketed in visibility commercially and in the public sector. This article describes the development of this field from early layered manufacturing approaches of photosculpture, topography, and material deposition. Certain precursors to modern AM processes are also briefly described. The growth of the field over the last 30 years is presented. Included is the standard delineation of AM technologies into seven broad categories. The economics of AM part generation is considered, and the impacts of the economics on application sectors are described. On the basis of current trends, the future outlook will include a convergence of AM fabricators, mass-produced AM fabricators, enabling of topology optimization designs, and specialization in the AM legal arena. Long-term developments with huge impact are organ printing and volume-based printing.

  16. New addition curing polyimides

    NASA Technical Reports Server (NTRS)

    Frimer, Aryeh A.; Cavano, Paul

    1991-01-01

    In an attempt to improve the thermal-oxidative stability (TOS) of PMR-type polymers, the use of 1,4-phenylenebis (phenylmaleic anhydride) PPMA, was evaluated. Two series of nadic end-capped addition curing polyimides were prepared by imidizing PPMA with either 4,4'-methylene dianiline or p-phenylenediamine. The first resulted in improved solubility and increased resin flow while the latter yielded a compression molded neat resin sample with a T(sub g) of 408 C, close to 70 C higher than PME-15. The performance of these materials in long term weight loss studies was below that of PMR-15, independent of post-cure conditions. These results can be rationalized in terms of the thermal lability of the pendant phenyl groups and the incomplete imidization of the sterically congested PPMA. The preparation of model compounds as well as future research directions are discussed.

  17. S-OO bond dissociation energies and enthalpies of formation of the thiomethyl peroxyl radicals CH{sub 3}S(O){sub n}OO (n=0,1,2)

    SciTech Connect

    Salta, Zoi; Kosmas, Agnie Mylona; Lesar, Antonija

    2014-10-06

    Optimized geometries, S-OO bond dissociation energies and enthalpies of formation for a series of thiomethyl peroxyl radicals are investigated using high level ab initio and density functional theory methods. The results show that the S-OO bond dissociation energy is largest in the methylsulfonyl peroxyl radical, CH{sub 3}S(O){sub 2}OO, which contains two sulfonic type oxygen atoms followed by the methylthiyl peroxyl radical, CH{sub 3}SOO. The methylsulfinyl peroxyl radical, CH{sub 3}S(O)OO, which contains only one sulfonic type oxygen shows the least stability with regard to dissociation to CH{sub 3}S(O)+O{sub 2}. This stabilization trend is nicely reflected in the variations of the S-OO bond distance which is found to be shortest in CH{sub 3}S(O){sub 2}OO and longest in CH{sub 3}S(O)OO.

  18. Use of nano-composite component to improve the conductivity and mechanical properties of Li{sub 2}SO{sub 4}-Al{sub 2}O{sub 3} solid electrolyte

    SciTech Connect

    Melnik, Juri; An Weizhu; Wei Guolin; Luo Jingli . E-mail: jingli.luo@ualberta.ca; Sanger, Alan R.; Chuang, Karl T.

    2006-10-12

    The microstructure, density, and conductivity of Li{sub 2}SO{sub 4} ion-conducting membranes incorporating nano-composite Li{sub 2}SO{sub 4}-Al{sub 2}O{sub 3} prepared using a sol-gel technique are superior to membranes having the same bulk composition prepared from mixtures of lithium sulfate and fine alumina powder. Properties of membranes made from the nano-composite material depend on both the overall composition and the preparative parameters. The relationships between preparative parameters, microstructure, and properties have been determined, from which we have found the optimum lithium sulfate content and thermal treatment parameters for manufacture of membranes with minimum gas permeability and maximum ionic conductivity.

  19. Synthesis, structure determination, and infrared spectroscopy of (NpO{sub 2}){sub 2}(SO{sub 4})(H{sub 2}O){sub 4}: Prevalence of cation-cation interactions and cationic nets in neptunyl sulfate compounds

    SciTech Connect

    Forbes, T.Z. Burns, P.C.

    2009-01-15

    The compound (NpO{sub 2}){sub 2}(SO{sub 4})(H{sub 2}O){sub 4} was synthesized by evaporation of a Np{sup 5+} sulfate solution. The crystal structure was determined using single crystal X-ray diffraction and refined to an R{sub 1}=0.0310. (NpO{sub 2}){sub 2}(SO{sub 4})(H{sub 2}O){sub 4} crystallizes in triclinic space group P-1, a=8.1102(7) A, b=8.7506(7) A, c=16.234(1) A, {alpha}=90.242(2){sup o}, {beta}=92.855(2){sup o}, {gamma}=113.067(2){sup o}, V=1058.3(2) A{sup 3}, and Z=2. The structure contains neptunyl pentagonal bipyramids that share vertices through cation-cation interactions to form a sheet or cationic net. The sheet is decorated on each side by vertex sharing with sulfate tetrahedra, and adjacent sheets are linked together through hydrogen bonding. A graphical representation of (NpO{sub 2}){sub 2}(SO{sub 4})(H{sub 2}O){sub 4} was constructed to facilitate the structural comparison to similar Np{sup 5+} compounds. The prevalence of the cationic nets in neptunyl sulfate compounds related to the overall stability of the structure is also discussed. - Graphical abstract: (NpO{sub 2}){sub 2}(SO{sub 4})(H{sub 2}O){sub 4} was synthesized by hydrothermal methods and its structure determined. A graphical representation of the compound was constructed to facilitate the structural comparison to similar Np{sup 5+} compounds and the prevalence of the cationic nets in neptunyl sulfate compounds related to the overall stability of the structure is discussed.

  20. High-throughput and microwave investigation of rare earth phosphonatoethanesulfonates-Ln(O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}) (Ln=Ho, Er, Tm, Yb, Lu, Y)

    SciTech Connect

    Sonnauer, Andreas

    2008-11-15

    Following the strategy of using bifunctional phosphonic acids for the synthesis of new metal phosphonates, the flexible ligand 2-phosphonoethanesulfonic acid, H{sub 2}O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}H (H{sub 3}L), was used in a high-throughput (HT) and microwave investigation of rare earth phosphonatoethanesulfonates. The HT-investigation led to six isotypic compounds Ln(O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}) with Ln=Ho (1), Er (2), Tm (3), Yb (4), Lu (5) and Y (6). The syntheses were scaled-up in glass reactor tubes in order to obtain larger amounts for a detailed characterization. Based on these results all compounds could be also synthesized by microwave-assisted heating and the influence of reaction time and stirring rate during the synthesis was established. For compound 2 the crystal structure was determined by single-crystal X-ray diffraction. The compounds contain isolated slightly distorted LnO{sub 6} octahedra that are connected by the phosphonate and sulfonate groups into a three-dimensional framework. Thermogravimetric investigations demonstrate the high thermal stability of the compounds up to 460 deg. C. - Graphical abstract: A high-throughput and microwave investigation of the System LnX{sub 3}/H{sub 2}O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}/NaOH/H{sub 2}O led to six new compounds Ln(O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}) with Ln=Ho, Er, Tm, Yb, Lu, Y.

  1. Modified GDP through health cost analysis of air pollution: The case of Turkey

    SciTech Connect

    Zaim, K.K.

    1999-02-01

    Economic growth and performance is monitored through the gross domestic product (GDP) of a nation. It has long been recognized that the traditionally computed GDP does not account for gains and losses observed due to the consumption of natural resources and environmental services. Hence, the objective of this study is to modify the Turkish GDP by taking social cost associated with air pollution into consideration. To this end health benefits and economic costs of air-quality improvement are estimated. The computations are based on the dose-response coefficients reported in several studies. The results indicate that a decrease in PM{sub 10} and SO{sub 2} levels to the WHO guideline would have resulted in a total of 48.309 {times} 10{sup 10} and 153.38 {times} 10{sup 10} Turkish lira savings in 1990 and 1993, respectively. These correspond to 0.12% and 0.08% of 1990 and 1993 GDPs, respectively.

  2. Remote air pollution measurement

    NASA Technical Reports Server (NTRS)

    Byer, R. L.

    1975-01-01

    This paper presents a discussion and comparison of the Raman method, the resonance and fluorescence backscatter method, long path absorption methods and the differential absorption method for remote air pollution measurement. A comparison of the above remote detection methods shows that the absorption methods offer the most sensitivity at the least required transmitted energy. Topographical absorption provides the advantage of a single ended measurement, and differential absorption offers the additional advantage of a fully depth resolved absorption measurement. Recent experimental results confirming the range and sensitivity of the methods are presented.

  3. Air conditioning and refrigeration engineering

    SciTech Connect

    Kreith, F.

    1999-12-01

    This book supplies the basics of design, from selecting the optimum system and equipment to preparing the drawings and specifications. It discusses the four phases of preparing a project: gathering information, developing alternatives, evaluating alternatives, and selling the best solution. In addition, the author breaks down the responsibilities of the engineer design documents, computer aided design, and government codes and standards. It provides you with an easy reference to all aspects of the topic. This resource addresses the most current areas of interest, such as computer aided design and drafting, desiccant air conditioning and energy conservation. It is a thorough and convenient guide to air conditioning and refrigeration engineering. Contents include: introduction; psychrometrics; air-conditioning processes and cycles; refrigerants and refrigeration cycles; outdoor design conditions and indoor design criteria; load calculations; air handling units and packaged units; refrigeration components and evaporative coolers; water systems; heating systems; refrigeration systems; thermal storage system; air system basics; absorption systems; air-conditioning systems and selection; and desiccant dehumidification and air-conditioning.

  4. Manual on indoor air quality

    SciTech Connect

    Diamond, R.C.; Grimsrud, D.T.

    1983-12-01

    This reference manual was prepared to assist electric utilities in helping homeowners, builders, and new home buyers to understand a broad range of issues related to indoor air quality. The manual is directed to technically knowledgeable persons employed by utility companies - the customer service or marketing representative, applications engineer, or technician - who may not have specific expertise in indoor air quality issues. In addition to providing monitoring and control techniques, the manual summarizes the link between pollutant concentrations, air exchange, and energy conservation and describes the characteristics and health effects of selected pollutants. Where technical information is too lengthy or complex for inclusion in this volume, reference sources are given. Information for this manual was gathered from technical studies, manufacturers' information, and other materials from professional societies, institutes, and associations. The aim has been to provide objective technical and descriptive information that can be used by utility personnel to make informed decisions about indoor air quality issues.

  5. (Draft) Community air pollution and mortality: Analysis of 1980 data from US metropolitan areas

    SciTech Connect

    Lipfert, F.W.

    1992-11-01

    1980 data from up to 149 metropolitan areas were used to define cross-sectional associations between community air pollution and ``excess`` human mortality. The regression model proposed by Ozkaynak and Thurston (1987), which accounted for age, race, education, poverty, and population density, was evaluated and several new models were developed. The new models also accounted for migration, drinking water hardness, and smoking, and included a more detailed description of race. Cause-of-death categories analyzed include all causes, all ``non-external`` causes, major cardiovascular diseases, and chronic obstructive pulmonary diseases (COPD). Both annual mortality rates and their logarithms were analyzed. Air quality data were obtained from the EPA AIRS database (TSP, SO{sub 4}{sup =}, Mn, and ozone) and from the inhalable particulate network (PM{sub 15}, PM{sub 2.5} and SO{sub 4}{sup =}, for 63{sup 4} locations). The data on particulates were averaged across all monitoring stations available for each SMSA and the TSP data were restricted to the year 1980. The associations between mortality and air pollution were found to be dependent on the socioeconomic factors included in the models, the specific locations included in the data set, and the type of statistical model used. Statistically significant associations were found as follows: between TSP and mortality due to non-external causes with log-linear models, but not with a linear model betweenestimated 10-year average (1980--90) ozone levels and 1980 non-external and cardiovascular deaths; and between TSP and COPD mortality for both linear and log-linear models. When the sulfate contribution to TSP was subtracted, the relationship with COPD mortality was strengthened.

  6. (Draft) Community air pollution and mortality: Analysis of 1980 data from US metropolitan areas

    SciTech Connect

    Lipfert, F.W.

    1992-11-01

    1980 data from up to 149 metropolitan areas were used to define cross-sectional associations between community air pollution and excess'' human mortality. The regression model proposed by Ozkaynak and Thurston (1987), which accounted for age, race, education, poverty, and population density, was evaluated and several new models were developed. The new models also accounted for migration, drinking water hardness, and smoking, and included a more detailed description of race. Cause-of-death categories analyzed include all causes, all non-external'' causes, major cardiovascular diseases, and chronic obstructive pulmonary diseases (COPD). Both annual mortality rates and their logarithms were analyzed. Air quality data were obtained from the EPA AIRS database (TSP, SO[sub 4][sup =], Mn, and ozone) and from the inhalable particulate network (PM[sub 15], PM[sub 2.5] and SO[sub 4][sup =], for 63[sup 4] locations). The data on particulates were averaged across all monitoring stations available for each SMSA and the TSP data were restricted to the year 1980. The associations between mortality and air pollution were found to be dependent on the socioeconomic factors included in the models, the specific locations included in the data set, and the type of statistical model used. Statistically significant associations were found as follows: between TSP and mortality due to non-external causes with log-linear models, but not with a linear model betweenestimated 10-year average (1980--90) ozone levels and 1980 non-external and cardiovascular deaths; and between TSP and COPD mortality for both linear and log-linear models. When the sulfate contribution to TSP was subtracted, the relationship with COPD mortality was strengthened.

  7. Air Leakage and Air Transfer Between Garage and Living Space

    SciTech Connect

    Rudd, A.

    2014-09-01

    This research project focused on evaluation of air transfer between the garage and living space in a single-family detached home constructed by a production homebuilder in compliance with the 2009 International Residential Code and the 2009 International Energy Conservation Code. The project gathered important information about the performance of whole-building ventilation systems and garage ventilation systems as they relate to minimizing flow of contaminated air from garage to living space. A series of 25 multi-point fan pressurization tests and additional zone pressure diagnostic testing characterized the garage and house air leakage, the garage-to-house air leakage, and garage and house pressure relationships to each other and to outdoors using automated fan pressurization and pressure monitoring techniques. While the relative characteristics of this house may not represent the entire population of new construction configurations and air tightness levels (house and garage) throughout the country, the technical approach was conservative and should reasonably extend the usefulness of the results to a large spectrum of house configurations from this set of parametric tests in this one house. Based on the results of this testing, the two-step garage-to-house air leakage test protocol described above is recommended where whole-house exhaust ventilation is employed. For houses employing whole-house supply ventilation (positive pressure) or balanced ventilation (same pressure effect as the Baseline condition), adherence to the EPA Indoor airPLUS house-to-garage air sealing requirements should be sufficient to expect little to no garage-to-house air transfer.

  8. Large scale air monitoring: lichen vs. air particulate matter analysis.

    PubMed

    Rossbach, M; Jayasekera, R; Kniewald, G; Thang, N H

    1999-07-15

    Biological indicator organisms have been widely used for monitoring and banking purposes for many years. Although the complexity of the interactions between organisms and their environment is generally not easily comprehensible, environmental quality assessment using the bioindicator approach offers some convincing advantages compared to direct analysis of soil, water, or air. Measurement of air particulates is restricted to experienced laboratories with access to expensive sampling equipment. Additionally, the amount of material collected generally is just enough for one determination per sampling and no multidimensional characterization might be possible. Further, fluctuations in air masses have a pronounced effect on the results from air filter sampling. Combining the integrating property of bioindicators with the world wide availability and particular matrix characteristics of air particulate matter as a prerequisite for global monitoring of air pollution is discussed. A new approach for sampling urban dust using large volume filtering devices installed in air conditioners of large hotel buildings is assessed. A first experiment was initiated to collect air particulates (300-500 g each) from a number of hotels during a period of 3-4 months by successive vacuum cleaning of used inlet filters from high volume air conditioning installations reflecting average concentrations per 3 months in different large cities. This approach is expected to be upgraded and applied for global monitoring. Highly positive correlated elements were found in lichens such as K/S, Zn/P, the rare earth elements (REE) and a significant negative correlation between Hg and Cu was observed in these samples. The ratio of concentrations of elements in dust and Usnea spp. is highest for Cz, Zn and Fe (400-200) and lowest for elements such as Ca, Rb, and Sr (20-10). PMID:10474261

  9. Metal-Air Batteries

    SciTech Connect

    Zhang, Jiguang; Bruce, Peter G.; Zhang, Gregory

    2011-08-01

    Metal-air batteries have much higher specific energies than most currently available primary and rechargeable batteries. Recent advances in electrode materials and electrolytes, as well as new designs on metal-air batteries, have attracted intensive effort in recent years, especially in the development of lithium-air batteries. The general principle in metal-air batteries will be reviewed in this chapter. The materials, preparation methods, and performances of metal-air batteries will be discussed. Two main metal-air batteries, Zn-air and Li-air batteries will be discussed in detail. Other type of metal-air batteries will also be described.

  10. AMBIENT AIR MONITORING STRATEGY

    EPA Science Inventory

    The Clean Air Act requires EPA to establish national ambient air quality standards and to regulate as necessary, hazardous air pollutants. EPA uses ambient air monitoring to determine current air quality conditions, and to assess progress toward meeting these standards and relat...

  11. High temperature corrosion studies. A. Iron: based superalloy in SO/sub 2//O/sub 2/ atmospheres. B. Gas: solid reaction with formation of volatile species

    SciTech Connect

    Liu, T.K.

    1980-03-01

    The thermogravimetric method was used to study high temperature corrosion under SO/sub 2//O/sub 2/ atmosphere applied to Armco 18SR alloys with different heat treatment histories, Armco T310 and pure chromium between 750 and 1100/sup 0/C. The weight gain follows the parabolic rate law. The volatilization of the protective Cr/sub 2/O/sub 3/ layer via formation of CrO/sub 3/ was taken into account above 900/sup 0/C for long time runs. The parabolic rate and the volatilization rate, derived from fitting the experimental data to the modified Tedmon's non-linear model, were correlated using the Arrhenius equation. Armco 18SR-C has the best corrosion resistance of the Armco 18SR alloys. Armco T310 is not protective at high temperatures. The available rate data on the oxidation of chromium oxide, chlorination of chromium, oxidation-chlorination of chromium oxide, chlorination of nickel and chlorination of iron were found to be predictable. The calculation of high temperature volatilization rate was performed using the available fluid correlation equations and the Lennard-Jones parameters derived from the molecule with similar structure and from the low temperature viscosity measurement. The lower predicted volatilization rate is due to the use of the Chapman-Enskog equation with the Lennard-Jones parameters mostly derived from the low temperature viscosity measurement. This was substantiated by comparing the reliable high temperature diffusion rate in the literature with the above mentioned calculational method. The experimental volatilization rates of this study are compared with the other related studies and the mass transfer predictions.

  12. Office Building Occupant's Guide to Indoor Air Quality

    MedlinePlus

    ... building ventilation systems; moisture and humidity; and occupant perceptions and susceptibilities. In addition, there are many other factors that affect comfort or perception of indoor air quality. Controlling indoor air quality ...

  13. Community air monitoring and the Village Green Project

    EPA Science Inventory

    Abstract: Cost and logistics are practical issues that have historically constrained the number of locations where long-term, active air pollution measurement is possible. In addition, traditional air monitoring approaches are generally conducted by technical experts with limite...

  14. Our Air: Unfit for Trees.

    ERIC Educational Resources Information Center

    Dochinger, Leon S.

    To help urban, suburban, and rural tree owners know about air pollution's effects on trees and their tolerance and intolerance to pollutants, the USDA Forest Service has prepared this booklet. It answers the following questions about atmospheric pollution: Where does it come from? What can it do to trees? and What can we do about it? In addition,…

  15. Urban air quality of Kathmandu valley

    SciTech Connect

    Sharma, C.K.

    1996-12-31

    The oval shaped tectonic basin of Kathmandu valley occupying about 600 sq. km. of area is situated in the middle sector of Himalayan range. There are three districts in the alley, i.e. Kathmandu, Litilpur, and Bhaktapur. Out of the three the most populated is the Kathmandu city (the capital of Kingdom of Nepal) which has 668,000 population in an area of approximately 50 sq. km. The city population consumes energy about 1/3 of total imports of Nepal in the form of gasoline, diesel, kerosene, furnace oil and cooking gas. This has resulted heavy pollution of air in the city leading bronchitis, and throat and chest diseases. Vehicle has increased several fold leading in recent months to 100,000 in number in a road of about 900 kms., out of which 25% is only metalled. Most of two and three wheelers are polluting the air by emission gases as well as dust particulate. SO{sub 2} has been found to go as high as 202 micro grams per cubic meter and NO{sub 2} to 126 micro gram particularly in winter months when a thick layer of fog covers the valley up to 10:00 AM in the morning. All the gases are mixed within the limited air below the fog and the ground. This creates the problem. Furthermore, municipal waste of 500 m{sup 3} a day and also liquid waste directly dumping in Bagmati river to the tune of 500,000 liters per day makes city ugly and filthy. Unless pollution of air, water, and land are controlled in time, Nepal will lose much of its foreign exchange earnings from tourist industry. It is found that tourist arrivals are considerably reduced in recent years and most of hotels occupancy is 50 to 60% in peak time. Nepal is trying to introduce legal frame work for pollution control but it will take time to be effective like in other developing countries unless government is strong.

  16. Synthesis and characterization of 2-phosphonoethanesulfonic acid and a barium-hydrogenphosphonatoethanesulfonate - BaH(O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3})

    SciTech Connect

    Sonnauer, Andreas

    2008-03-15

    Following the strategy of using polyfunctional phosphonic acids for the synthesis of new metal phosphonates, the organic linker molecule 2-phosphonoethanesulfonic acid, H{sub 2}O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}H (1) (H{sub 3}L), was synthesized and characterized in detail. The acid was used in a high-throughput (HT) investigation of the system BaCl{sub 2}/H{sub 3}L/NaOH/H{sub 2}O. The HT experiments comprising 48 individual hydrothermal reactions were performed to systematically investigate the influence of pH of the starting mixture as well as the molar ratio Ba{sup 2+}: H{sub 3}L. Only two reaction products were observed: small amounts of BaCO{sub 3} under basic conditions and BaH(O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}) (2). For compounds 1 and 2 the crystal structures were determined from single-crystal X-ray diffraction data (H{sub 2}O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}H: trigonal, P3{sub 2}, a=814.58(1), c=861.20(2) pm, Z=3, R1=0.0254, wR{sub 2}=0.0758 for I>2{sigma}(I); BaH(O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}): orthorhombic, Ibam, a=953.39(19), b=855.55(17), c=867.82(17) pm, Z=4, R1=0.0162, wR{sub 2}=0.0417 for I>2{sigma}(I)). The structure of H{sub 3}L (1) is stabilized exclusively by strong hydrogen bonds. Compound 2 is built up by chains of edge sharing BaO{sub 8} polyhedra. These chains are connected to a three-dimensional network by the -CH{sub 2}CH{sub 2}- linker of the ligand. Thermogravimetric investigation of compound 2, as well as IR spectra of 1 and 2 are presented. - Graphical abstract: The synthesis of the ligand H{sub 2}O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}H and its use in the systematic investigation in the system BaCl{sub 2}/H{sub 2}O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}H/NaOH/H{sub 2}O led to the new barium phosphonatosulfonate BaH(O{sub 3}P-C{sub 2}H{sub 4}-SO{sub 3}H)

  17. Air blown gasification cycle

    SciTech Connect

    Dawes, S.G.; Mordecai, M.; Brown, D.; Burnard, G.K.

    1995-12-31

    The Air Blown Gasification Cycle (ABGC) is a hybrid partial gasification cycle based on a novel, air blown pressurized fluidized bed gasifier (PFBG) with a circulating fluidized bed combustor (CFBC) to burn the residual char from the PFBG. The ABGC has been developed primarily as a clean coal generation system and embodies a sulfur capture mechanism based on the addition of limestone, or other sorbent, to the PFBG where it is sulfided in the reducing atmosphere, followed by oxidation to a stable sulfate residue in the CFBC. In order to achieve commercialization, certain key technological issues needed to be addressed and an industry-led consortium was established to develop the components of the system through the prototype plant to commercial exploitation. The consortium, known as the Clean Coal Power Generation Group (CCPGG), is undertaking a program of activity aimed at achieving a design specification for a 75 MWe prototype integrated plant by March, 1996. Component development consists of both the establishment of new components, such as the PFBG and the hot gas clean up system, and specific development of already established components, such as the CFBC, raw gas cooler, heat recovery steam generator (HRSG) and gas turbine. This paper discusses the component development activities and indicates the expected performance and economics of both the prototype and commercial plants. In addition, the strategy for component development and achievement of the specification for a 75 MWe prototype integrated plant is described.

  18. High efficiency air cycle air conditioning system

    SciTech Connect

    Rannenberg, G. C.

    1985-11-19

    An air cycle air conditioning system is provided with regenerative heat exchangers upstream and downstream of an expansion turbine. A closedloop liquid circulatory system serially connects the two regenerative heat exchangers for regeneration without the bulk associated with air-to-air heat exchange. The liquid circulatory system may also provide heat transport to a remote sink heat exchanger and from a remote load as well as heat exchange within the sink heat exchanger and load for enhanced compactness and efficiency.

  19. Evaluation of a possible association of urban air toxics and asthma

    SciTech Connect

    Leikauf, G.D.; Kline, S.; Albert, R.E.; Baxter, C.S.

    1995-09-01

    The prevalence of asthma, measured either as the frequency of hospital admission or number of deaths attributed to asthma, has increased over the last 15 to 20 years. Rapid increases in disease prevalence are more likely to be attributable to environmental than genetic factors. inferring from past associations between air pollution and asthma, it is feasible that changes in the ambient environment could contribute to this increase in morbidity and mortality. Scientific evaluation of the links between air pollution and the exacerbation of asthma is incomplete, however. Currently, criteria pollutants [SO{sub x}NO{sub x}, O{sub 3}, CO, Pb, particulate matter (PM{sub 10})] and other risk factors (exposure to environmental tobacco smoke, volatile organic compounds, etc.) are constantly being evaluated as to their possible contributions to this situation. Data from these studies suggest that increases in respiratory disease are associated with exposures to ambient concentrations of particulate and gaseous pollutants. Similarly, exposure to environmental tobacco smoke, also a mixture of particles and gases and that current measurements of air pollution are, in part, indirect in that the concentrations of criteria pollutants are acting as surrogates of our exposure to a complex mixture. Other irritant air pollutants, including certain urban air toxics, are associated with asthma in occupational settings and may interact with criteria pollutants in ambient air to exacerbate asthma. 179 refs., 2 figs., 18 tabs.

  20. Ambient air pollution exposure and the incidence of related health effects among racial/ethnic minorities

    SciTech Connect

    Nieves, L.A.; Wernette, D.R.

    1997-02-01

    Differences among racial and ethnic groups in morbidity and mortality rates for diseases, including diseases with environmental causes, have been extensively documented. However, documenting the linkages between environmental contaminants, individual exposures, and disease incidence has been hindered by difficulties in measuring exposure for the population in general and for minority populations in particular. After briefly discussing research findings on associations of common air pollutants with disease incidence, the authors summarize recent studies of radial/ethnic subgroup differences in incidence of these diseases in the US. They then present evidence of both historic and current patterns of disproportionate minority group exposure to air pollution as measured by residence in areas where ambient air quality standards are violated. The current indications of disproportionate potential exposures of minority and low-income populations to air pollutants represent the continuation of a historical trend. The evidence of linkage between disproportionate exposure to air pollution of racial/ethnic minorities and low-income groups and their higher rates of some air pollution-related diseases is largely circumstantial. Differences in disease incidence and mortality rates among racial/ethnic groups are discussed for respiratory diseases, cancers, and lead poisoning. Pollutants of concern include CO, Pb, SO{sub 2}, O{sub 3}, and particulates.