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Sample records for limestone injection dry

  1. Management of solid wastes from the Limestone Injection Dry Scrubbing (LIDS) clean coal technology. Final report

    SciTech Connect

    Musiol, W.F. Jr.; Czuczwa, J.M.

    1993-03-01

    The objectives of this project were to characterize by-products from a pilot Limestone Injection Dry Scrubbing (LIDS) process and to develop processes directed toward the safe and economic use or disposal of these wastes. Because LIDS is a developing Clean Coal technology, a database of chemical and physical characteristics of the by-product was first developed. During the course of this project, it was found that the waste alone did not form high-strength products sufficient for use in construction and engineering applications. Therefore, the project was redirected to evaluate the by-product as a soil-cement and Portland cement raw material, agricultural liming agent, backfill/landfill material component, and mine reclamation/neutralizing agent. Based on these evaluations, the most viable uses for the LIDS byproduct include use in mine reclamation or as a neutralization agent. If soluble sulfites can be minimized by avoiding a dolomitic LIDS reagent, use as an agricultural liming agent has promise. Interest from an Ohio utility in the LIDS process suggests possible application of results at the demonstration or commercial stages.

  2. STEAM INJECTION INTO FRACTURED LIMESTONE AT LORING AIR FORCE BASE

    EPA Science Inventory

    A research project on steam injection for the remediation of spent chlorinated solvents from fractured limestone was recently undertaken at the former Loring AFB in Limestone, ME. Participants in the project include the Maine Department of Environmental Protection, EPA Region I,...

  3. Modified dry limestone process for control of sulfur dioxide emissions

    DOEpatents

    Shale, Correll C.; Cross, William G.

    1976-08-24

    A method and apparatus for removing sulfur oxides from flue gas comprise cooling and conditioning the hot flue gas to increase the degree of water vapor saturation prior to passage through a bed of substantially dry carbonate chips or lumps, e.g., crushed limestone. The reaction products form as a thick layer of sulfites and sulfates on the surface of the chips which is easily removed by agitation to restore the reactive surface of the chips.

  4. Optimization of Trona/Limestone Injection for SO2 Control in Coal-Fired Boilers

    SciTech Connect

    2005-09-01

    Mobotec USA develops and markets air pollution control systems for utility boilers and other combustion systems. They have a particular interest in technologies that can reduce NOx, SOx, and mercury emissions from coal-fired boilers, and have been investigating the injection of sorbents such as limestone and trona into a boiler to reduce SOx and Hg emissions. WRI proposed to use the Combustion Test Facility (CTF) to enable Mobotec to conduct a thorough evaluation of limestone and trona injection for SO{sub 2} control. The overall goal of the project was to characterize the SO{sub 2} reductions resulting from the injection of limestone and trona into the CTF when fired with a high-sulfur eastern bituminous coal used in one of Mobotec's Midwest installations. Results revealed that when limestone was injected at Ca:S molar ratios of 1.5 to 3.0, the resulting SO{sub 2} reductions were 35-55%. It is believed that further reductions can be attained with improved mixing of the sorbent with the combustion gases. When limestone was added to the coal, at Ca:S molar ratios of 0.5 to 1.5, the SO{sub 2} reductions were 13-21%. The lower reductions were attributed to dead-burning of the sorbent in the high temperature flame zone. In cases where limestone was both injected into the furnace and added to the coal, the total SO{sub 2} reductions for a given Ca:S molar ratio were similar to the reductions for furnace injection only. The injection of trona into the mid-furnace zone, for Na:S molar ratios of 1.4 to 2.4, resulted in SO{sub 2} reductions of 29-43%. Limestone injection did not produce any slag deposits on an ash deposition probe while trona injection resulted in noticeable slag deposition.

  5. Full-scale results for TAM limestone injection

    SciTech Connect

    Baer, S.

    1996-12-31

    Information is outlined on the use of thermally active marble (TAM) sorbents in boilers. Data are presented on: the comparison of TAM to limestone; NOVACON process development history; CFB test history; CFB pilot scale test; full-scale CFB trial; August, 1996 CFB demonstration; Foster Wheeler Mount Carmel sorbent feed rate comparison and Ca:S comparison; unburned carbon is ash; and advantages and savings in CFB boilers.

  6. Monitoring regional effects of high pressure injection of wastewater in a limestone aquifer

    USGS Publications Warehouse

    Faulkner, Glen L.; Pascale, Charles A.

    1975-01-01

    More than 10 billion gallons (38 × 106 m3) of acid industrial liquid waste has been injected in about 11 years under high pressure into a saline-water-filled part of a limestone aquifer of low transmissivity between 1,400 and 1,700 feet (430 and 520 m) below land surface near Pensacola, Florida. A similar waste disposal system is planned for the same zone at a site about 8.5 miles (13.7 km) to the east. The injection zone is the lower limestone of the Floridan aquifer. The lower limestone is overlain by a confining layer of plastic clay about 220 feet (67 m) thick at the active injection site and underlain by another confining layer of shale and clay. The upper confining layer is overlain by the upper limestone of the Floridan aquifer.The active injection system consists of two injection wells about a quarter of a mile (0.4 km) apart and three monitor wells. Two of the monitor wells (deep monitors) are used to observe hydraulic and geochemical effects of waste injection in the injection zone at locations about 1.5 miles (2.4 km) south and 1.9 miles (3.1 km) north of the center of the injection site. The third well (shallow monitor), used to observe any effects in the upper limestone, is about 100 feet (30 m) from one of the injection wells. Since 1972 the injection zone has also been monitored at a test well at the planned new injection site. Three more monitor wells in the injection zone were activated in early 1974 at sites 17 miles (27 km) northeast, 22 miles (35 km) east and 33 miles (53 km) northeast of the injection site. The six deep monitors provide a system for evaluating the regional effects of injecting wastes. No change in pressure or water quality due to injection was, by mid-1974, evident in the upper limestone at the injection site, but static pressures in the lower limestone at the site had increased 8 fold since injection began in 1963. Chemical analyses indicated probable arrival of the diluted waste at the south monitor well in 1973. By mid-1974

  7. Use of borehole radar tomography to monitor steam injection in fractured limestone

    USGS Publications Warehouse

    Gregoire, C.; Joesten, P.K.

    2006-01-01

    Borehole radar tomography was used as part of a pilot study to monitor steam-enhanced remediation of a fractured limestone contaminated with volatile organic compounds at the former Loring Air Force Base, Maine, USA. Radar tomography data were collected using 100-MHz electric-dipole antennae before and during steam injection to evaluate whether cross-hole radar methods could detect changes in medium properties resulting from the steam injection. Cross-hole levelrun profiles, in which transmitting and receiving antennae are positioned at a common depth, were made before and after the collection of each full tomography data set to check the stability of the radar instruments. Before tomographic inversion, the levelrun profiles were used to calibrate the radar tomography data to compensate for changes in traveltime and antenna power caused by instrument drift. Observed changes in cross-hole radar traveltime and attenuation before and during steam injection were small. Slowness- and attenuation-difference tomograms indicate small increases in radar slowness and attenuation at depths greater than about 22 m below the surface, consistent with increases in water temperature observed in the boreholes used for the tomography. Based on theoretical modelling results, increases in slowness and attenuation are interpreted as delineating zones where steam injection heating increased the electrical conductivity of the limestone matrix and fluid. The results of this study show the potential of cross-hole radar tomography methods to monitor the effects of steam-induced heating in fractured rock environments. ?? 2006 European Association of Geoscientists & Engineers.

  8. Laboratory study of SO2 dry deposition on limestone and marble: Effects of humidity and surface variables

    USGS Publications Warehouse

    Spiker, E. C.; Hosker, R.P.; Weintraub, V.C.; Sherwood, S.I.

    1995-01-01

    The dry deposition of gaseous air pollutants on stone and other materials is influenced by atmospheric processes and the chemical characteristics of the deposited gas species and of the specific receptor material. Previous studies have shown that relative humidity, surface moisture, and acid buffering capability of the receptor surface are very important factors. To better quantify this behavior, a special recirculating wind tunnel/environmental chamber was constructed, in which wind speed, turbulence, air temperature, relative humidity, and concentrations of several pollutants (SO2, O3, nitrogen oxides) can be held constant. An airfoil sample holder holds up to eight stone samples (3.8 cm in diameter and 1 cm thick) in nearly identical exposure conditions. SO2 deposition on limestone was found to increase exponentially with increasing relative humidity (RH). Marble behaves similarly, but with a much lower deposition rate. Trends indicate there is little deposition below 20% RH on clean limestone and below 60% RH on clean marble. This large difference is due to the limestone's greater porosity, surface roughness, and effective surface area. These results indicate surface variables generally limit SO2 deposition below about 70% RH on limestone and below at least 95% RH on marble. Aerodynamic variables generally limit deposition at higher relative humidity or when the surface is wet.The dry deposition of gaseous air pollutants on stone and other materials is influenced by atmospheric processes and the chemical characteristics of the deposited gas species and of the specific receptor material. Previous studies have shown that relative humidity, surface moisture, and acid buffering capability of the receptor surface are very important factors. To better quantify this behavior, a special recirculating wind tunnel/environmental chamber was constructed, in which wind speed, turbulence, air temperature, relative humidity, and concentrations of several pollutants (SO2, O3

  9. An Experimental Study on Normal Stress and Shear Rate Dependency of Basic Friction Coefficient in Dry and Wet Limestone Joints

    NASA Astrophysics Data System (ADS)

    Mehrishal, Seyedahmad; Sharifzadeh, Mostafa; Shahriar, Korosh; Song, Jae-Jon

    2016-12-01

    Among all parameters that affect the friction of rocks, variable normal stress and slip rate are the most important second-order parameters. The shear-rate- and normal-stress-dependent friction behavior of rock discontinuities may significantly influence the dynamic responses of rock mass. In this research, two limestone rock types, which were travertine and onyx marble with slickenside and grinded #80 surfaces, were prepared and CNL direct shear tests were performed on the joints under various shear conditions. The shearing rate varied from 0.1 to 50 mm/min under different normal stresses (from 2 to 30 % of UCS) in both dry and wet conditions. Experiments showed that the friction coefficient of slickensided and ground #80 surfaces of limestone increased with the increasing shear velocity and decreased with the increasing normal stress. Micro-asperity interlocking between ground #80 surfaces showed higher wear and an increase in friction coefficient ( µ) compared to slickensided surfaces. Slickensided samples with moist surfaces showed an increase in the coefficient of friction compared to dry surfaces; however, on ground #80 surfaces, the moisture decreased the coefficient of friction to a smaller value. Slickenside of limestone typically slides stably in a dry condition and by stick-slip on moist surfaces. The observed shear-rate- and normal-stress-dependent friction behavior can be explained by a similar framework to that of the adhesion theory of friction and a friction mechanism that involves the competition between microscopic dilatant slip and surface asperity deformation. The results have important implications for understanding the behavior of basic and residual friction coefficients of limestone rock surfaces.

  10. Chemical changes in an industrial waste liquid during post-injection movement in a limestone aquifer, Pensacola, Florida

    USGS Publications Warehouse

    Ehrlich, G.G.; Godsy, E.M.; Pascale, C.A.; Vecchioli, John

    1979-01-01

    An industrial waste liquid containing organonitrile compounds and nitrate ion has been injected into the lower limestone of the Floridan aquifer near Pensacola, Florida since June 1975. Chemical analyses of water from monitor wells and backflow from the injection well indicate that organic carbon compounds are converted to CO2 and nitrate is converted to N2. These transformations are caused by bacteria immediately after injection, and are virtually completed within 100 m of the injection well. The zone near the injection well behaves like an anaerobic filter with nitrate respiring bacteria dominating the microbial flora in this zone.Sodium thiocyanate contained in the waste is unaltered during passage through the injection zone and is used to detect the degree of mixing of injected waste liquid with native water at a monitor well 312 m (712 ft) from the injection well. The dispersivity of the injection zone was calculated to be 10 m (33 ft). Analyses of samples from the monitor well indicate 80 percent reduction in chemical oxygen demand and virtually complete loss of organonitriles and nitrate from the waste liquid during passage from the injection well to the monitor well. Bacterial densities were much lower at the monitor well than in backflow from the injection well.

  11. Determining the distribution of hydraulic conductivity in a fractured limestone aquifer by simultaneous injection and geophysical logging

    USGS Publications Warehouse

    Morin, R.H.; Hess, A.E.; Paillet, Frederick L.

    1988-01-01

    A field technique for assessing the vertical distribution of hydraulic conductivity in an aquifer was applied to a fractured carbonate formation in southeastern Nevada. The technique combines the simultaneous use of fluid injection and geophysical logging to measure in situ vertical distributions of fluid velocity and hydraulic head down the borehole; these data subsequently are analyzed to arrive at quantitative estimates of hydraulic conductivity across discrete intervals in the aquifer. The results of this analysis identified the contact margin between the Anchor and Dawn Members of the Monte Cristo Limestone as being the dominant transmissive unit. -from Authors

  12. Coalescence of dry foam under water injection.

    PubMed

    Mensire, Rémy; Piroird, Keyvan; Lorenceau, Elise

    2014-09-28

    When a small volume of pure water - typically a drop - is injected within an aqueous foam, it locally triggers the rupture of foam films, thus opening an empty cavity in the foam's bulk. We consider the final shape of this cavity and we quantify its volume as a function of the volume of injected water, the diameter of the bubbles and the liquid fraction of the foam. We provide quantitative understanding to explain how and when this cavity appears. We epitomize the dilution of surfactants at the water-air interfaces as the main cause lying behind the coalescence process. We identify a new coalescence regime for which a critical surfactant concentration rules the stability of the foam.

  13. Steam injection pilot study in a contaminated fractured limestone (Maine, USA): Modeling and analysis of borehole radar reflection data

    USGS Publications Warehouse

    Gregoire, C.; Lane, J.W.; Joesten, P.K.

    2005-01-01

    Steam-enhanced remediation (SER) has been successfully used to remove DNAPL and LNAPL contaminants in porous media. Between August and November 2002, SER was tested in fractured limestone at the former Loring Air Force Base, in Maine, USA. During the SER investigation, the U.S. Geological Survey conducted a series of borehole radar surveys to evaluate the effectiveness of radar methods for monitoring the movement of steam and heat through the fractured limestone. The data were collected before steam injection, 10 days after the beginning of injection, and at the end of injection. In this paper, reflection-mode borehole radar data from wells JBW-7816 and JBW-7817A are presented and discussed. Theoretical modeling was performed to predict the variation of fracture reflectivity owed to heating, to show displacement of water and to assess the effect of SER at the site. Analysis of the radar profile data indicates some variations resulting from heating (increase of continuity of reflectors, attenuation of deeper reflections) but no substantial variation of traveltimes. Spectral content analysis of several individual reflections surrounding the boreholes was used to investigate the replacement of water by steam in the fractures. Observed decrease in radar reflectivity was too small to be explained by a replacement of water by steam, except for two high-amplitude reflectors, which disappeared near the end of the injection; moreover, no change of polarity, consistent with steam replacing water, was observed. The decrease of amplitude was greater for reflectors near well JBW-7817A and is explained by a greater heating around this well.

  14. 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).

  15. Limestone Caverns

    ERIC Educational Resources Information Center

    Powell, Richard L.

    1970-01-01

    Describes the origin of limestone caverns, using Mammoth Cave as an example, with particular reference to the importance of groundwater information of caverns, the present condition of groundwater, and how caverns develop within fluctuating groundwater zones. (BR)

  16. Limestone geomorphology

    SciTech Connect

    Trudgill, S.

    1985-01-01

    This book focuses on recent work on geomorphological processes and relates them to established theories of landform development. Special attention is paid to soil processes, marine geomorphology, chemical processes and future work on process-form relationships in the context of dated sequences of cave deposits. There are discussions of limestone landforms and other carbonate rocks, caves, hydrological networks, features of karst, morphometry, and coastal landforms and solution chemistry of limestones.

  17. Dry injection flue gas desulfurization process using absorptive soda ash sorbent

    SciTech Connect

    Cyran, M.J.; Copenhafer, W.C.

    1986-05-13

    A dry injection flue gas desulfurization process is described which comprises injecting a dry soda ash sorbent, which is a particulate solid derived from calcination under non-sintering conditions of a NaHCO/sub 3/-containing compound, into a SO/sub 2/-contaminated flue gas stream that contains moisture in an amount of 0.5-10 wt% H/sub 2/O and is at a temperature of 100/sup 0/-175/sup 0/C; providing an amount of injected sorbent and sufficient gas-sorbent contact time such that a substantial portion, at least 40%, of the sorbent sodium content is utilized at NSR=1, in reducing the concentration of SO/sub 2/ in the gas stream, collecting the sorbent in a solids-collection device which is a fabric filter baghouse or an electrostatic precipitator; discharging collected sorbent from the solids-collection device; the dry soda ash sorbent being a porous calcine obtained from calcination of sodium sesquicarbonate, sodium bicarbonate, Wegscheider's salt or mixtures of these, and further characterized by having a minimum surface area of at least 2 m/sup 2//g and a residual bicarbonate content of less than 10 wt% NaHCO/sub 3/.

  18. Efficiency and safety of subconjunctival injection of anti-VEGF agent – bevacizumab – in treating dry eye

    PubMed Central

    Jiang, Xiaodan; Lv, Huibin; Qiu, Weiqiang; Liu, Ziyuan; Li, Xuemin; Wang, Wei

    2015-01-01

    Purpose Dry eye is a chronic inflammatory ocular surface disease with high prevalence. The current therapies for dry eye remain to be unspecific and notcomprehensive. This study aims to explore safety and efficacy of a novel treatment – subconjunctival injection of bevacizumab – in dry eye patients. Methods Sixty-four eyes of 32 dry eye patients received subconjunctival injection of 100 μL 25 mg/mL bevacizumab. Dry eye symptoms, signs (corrected visual acuity, intraocular pressure, conjunctival vascularity, corneal staining, tear break-up time, Marx line score, and blood pressure), and conjunctival impression cytology were evaluated 3 days before and 1 week, 1 month, and 3 months after injection. Results Significant improvements were observed in dry eye symptoms, tear break-up time, and conjunctival vascularization area at all the visits after injection compared to the baseline (P<0.05). The density of the goblet cell increased significantly at 1 month and 3 months after injection (P<0.05). There was no visual and systemic threat observed in any patient. Conclusion Subconjunctival injection of 100 μL 25 mg/mL bevacizumab is a safe and efficient treatment for ocular surface inflammation of dry eye disease. PMID:26109847

  19. LIFAC sorbent injection desulfurization demonstration project

    SciTech Connect

    Not Available

    1991-01-01

    LIFAC combines upper-furnace limestone injection followed by post-furnace humidification in an activation reactor located between the air preheater and the ESP. The process produces a dry and stable waste product that is partially removed from the bottom of the activation reactor and partially removed at the ESP.

  20. EVALUATION OF FGD DRY INJECTION SORBENTS AND ADDITIVES - VOLUME 2 - PILOT PLANT EVALUATION OF HIGH REACTIVITY SORBENTS

    EPA Science Inventory

    The report describes a mini-pilot test program to investigate potential new sorbents and processes for dry SO2 removal. Initial tests showed that the 85 cu m/h pilot plant could be used successfully to evaluate both spray dryer and dry injection processes using traditional calciu...

  1. Limestone compaction: an enigma

    USGS Publications Warehouse

    Shinn, Eugene A.; Halley, Robert B.; Hudson, J. Harold; Lidz, Barbara H.

    1977-01-01

    Compression of an undisturbed carbonate sediment core under a pressure of 556 kg/cm2 produced a “rock” with sedimentary structures similar to typical ancient fine-grained limestones. Surprisingly, shells, foraminifera, and other fossils were not noticeably crushed, which indicates that absence of crushed fossils in ancient limestones can no longer be considered evidence that limestones do not compact.

  2. Pilot scale-SO{sub 2} control by dry sodium bicarbonate injection and an electrostatic precipitator

    SciTech Connect

    Pliat, M.J.; Wilder, J.M.

    2007-10-15

    A 500 actual cubic feet gas per minute (acfm) pilot-scale SO{sub 2} control study was undertaken to investigate flue gas desulfurization (FGD) by dry sodium sorbents in 400{sup o}F (204.5{sup o}C) flue gases emitted from a coal fired boiler with flue gas concentrations between 350 and 2500 ppm SO{sub 2}. Powdered sodium alkaline reagents were injected into the hot flue gas downstream of the air preheater and the spent reagents were collected using an electrostatic precipitator. Three different sorbents were used: processed sodium bicarbonate of two particle sizes; solution mined sodium bicarbonate, and processed sodium sesquicarbonate. SO{sub 2} concentrations were measured upstream of the reagent injection, 25-ft (7.62 m) downstream of the injection point, and downstream of the electrostatic precipitator. SO{sub 2} collection efficiencies ranged from 40 to 80% using sodium bicarbonate stoichiometric ratios from 0.5 to 3.0. Much of the in-duct SO{sub 2} removal occurred during the first second of reagent reaction time, indicating that the sulfur dioxide-sodium reaction rates may be faster than have been measured for fixed bed measurements reported in the literature.

  3. INVESTIGATION AND DEMONSTRATION OF DRY CARBON-BASED SORBENT INJECTION FOR MERCURY CONTROL

    SciTech Connect

    Terry Hunt; Mark Fox; Lillian Stan; Sheila Haythornthwaite; Justin Smith; Jason Ruhl

    1998-10-01

    This quarterly report describes the activities that have taken place during the first full quarter of the Phase II project ''Investigation and Demonstration of Dry Carbon-Based Sorbent Injection for Mercury Control''. Modifications were completed and sampling began at the 600 acfm pilot-scale particulate control module (PCM) located at the Comanche Station in Pueblo, CO. The PCM was configured as an electrostatic precipitator for these tests. A Perkin-Elmer flue gas mercury analyzer was installed on-site and operated. Initial test results using both manual sampling methodology and the mercury analyzer are presented herein. Preparations were made during this period for full-scale mercury testing of several PSCo units. A site visit was made to Arapahoe and Cherokee Generating Stations to determine sample locations and to develop a test plan.

  4. Investigation and Demonstration of Dry Carbon-Based Sorbent Injection for Mercury Control

    SciTech Connect

    Jim Butz; Terry Hunt

    2005-11-01

    Public Service Company of Colorado and ADA Technologies, Inc. have performed a study of the injection of activated carbon for the removal of vapor-phase mercury from coal-fired flue gas streams. The project was completed under contract to the US Department of Energy's National Energy Technology Laboratory, with contributions from EPRI and Public Service Company. The prime contractor for the project was Public Service Company, with ADA Technologies as the major subcontractor providing technical support to all aspects of the project. The research and development effort was conducted in two phases. In Phase I a pilot facility was fabricated and tests were performed using dry carbon-based sorbent injection for mercury control on a coal-fired flue gas slipstream extracted from an operating power plant. Phase II was designed to move carbon injection technology towards commercial application on coal-fired power plants by addressing key reliability and operability concerns. Phase II field work included further development work with the Phase I pilot and mercury measurements on several of PSCo's coal-fired generating units. In addition, tests were run on collected sorbent plus fly ash to evaluate the impact of the activated carbon sorbent on the disposal of fly ash. An economic analysis was performed where pilot plant test data was used to develop a model to predict estimated costs of mercury removal from plants burning western coals. Testing in the pilot plant was undertaken to quantify the effects of plant configuration, flue gas temperature, and activated carbon injection rate on mercury removal. All three variables were found to significantly impact the mercury removal efficiency in the pilot. The trends were clear: mercury removal rates increased with decreasing flue gas temperature and with increasing carbon injection rates. Mercury removal was much more efficient with reverse-gas and pulse-jet baghouse configurations than with an ESP as the particulate control device

  5. Determination of dry carbon-based sorbent injection for mercury control in utility ESP and baghouses

    SciTech Connect

    Broderick, T.; Haythornthwaite, S.; Bell, W.; Selegue, T.; Perry, M.

    1998-12-31

    Domestic coal-fired power plants emit approximately 40 to 80 metric tons of mercury to the atmosphere annually. The mercury concentration in utility flue gas is in the dilute range of 0.1 to 1 parts per billion. The EPA is assessing whether such low concentrations of mercury emissions from coal-fired utilities pose any significant health risk and whether mercury regulations would be necessary or appropriate. In anticipation of possible mercury control regulations, ADA Technologies (ADA) and TDA Research, Inc (TDA) were funded by the Department of Energy (DOE) to evaluate carbon-based sorbents for mercury control at utility coal-fired power plants. Past investigations of the use of dry carbon-based sorbent injection for mercury control on pilot-scale utility flue gas applications have shown that these sorbents are capable of removing gas-phase mercury. ADA Technologies field-tested the mercury removal capability of several carbon-based sorbents manufactured by TDA. The test facility was a DOE-owned test facility built and operated by ADA at the Public Service Company of Colorado`s Comanche Station in Pueblo, Colorado. The pilot-scale test fixture is a 600-acfm particulate control module that can be configured as an electrostatic precipitator, a pulse-jet baghouse, or a reverse-gas baghouse. It extracts a slipstream of flue gas from a coal-fired utility boiler. Sorbent is injected into the flue gas slipstream upstream of the particulate control module and is removed by the module. ADA evaluated the mercury capture efficiency of the sorbents over a range of flue gas temperatures and injection rates. In addition, the effect of flyash on mercury capture was also investigated. The test facility is configured to take flue gas from either upstream or downstream of Comanche Station`s full-scale reverse-gas baghouse, allowing tests to be conducted with normal-ash or low-ash flue gas.

  6. Formation dry-out from CO2 injection into saline aquifers: Part 1, Effects of solids precipitation and their mitigation

    SciTech Connect

    Pruess, Karsten; Muller, Nadja

    2009-02-01

    Injection of CO{sub 2} into saline aquifers may cause formation dry-out and precipitation of salt near the injection well, which may reduce formation porosity, permeability, and injectivity. This paper uses numerical simulation to explore the role of different processes and parameters in the salt precipitation process and to examine injection strategies that could mitigate the effects. The main physical mechanisms affecting the dry-out and salt precipitation process include (1) displacement of brine away from the injection well by injected CO{sub 2}, (2) dissolution (evaporation) of brine into the flowing CO{sub 2} stream, (3) upflow of CO{sub 2} due to gravity effects (buoyancy), (4) backflow of brine toward the injection point due to capillary pressure gradients that oppose the pressure gradient in the CO{sub 2}-rich ('gas') phase, and (5) molecular diffusion of dissolved salt. The different mechanisms operate on a range of spatial scales. CO{sub 2} injection at constant rate into a homogeneous reservoir with uniform initial conditions is simulated in 1-D radial geometry, to resolve multiscale processes by taking advantage of the similarity property, i.e., the evolution of system conditions as a function of radial distance R and time t depends only on the similarity variable R{sup 2}/t. Simulations in 2-D vertical cross sections are used to examine the role of gravity effects. We find that counterflow of CO{sub 2} and brine can greatly increase aqueous phase salinity and can promote substantial salt precipitation even in formations with low dissolved solids. Salt precipitation can accentuate effects of gravity override. We find that injecting a slug of fresh water prior to commencement of CO{sub 2} injection can reduce salt precipitation and permeability loss near the injection well.

  7. Silicon interstitial injection during dry oxidation of SiGe /Si layers

    NASA Astrophysics Data System (ADS)

    Napolitani, E.; Di Marino, M.; De Salvador, D.; Carnera, A.; Spadafora, M.; Mirabella, S.; Terrasi, A.; Scalese, S.

    2005-02-01

    The injection of Si self-interstitial atoms during dry oxidation at 815°C of very shallow SiGe layers grown on Si (001) by molecular-beam epitaxy (MBE) has been investigated. We first quantified the oxidation enhanced diffusion (OED) of two boron deltas buried into the Si underlying the oxidized SiGe layers. Then, by simulating the interstitial diffusion in the MBE material with a code developed on purpose, we estimated the interstitial supersaturation (S) at the SiGe /Si interface. We found that S (a) is lower than that observed in pure Si, (b) is Ge-concentration dependent, and (c) has a very fast transient behavior. After such a short transient, the OED is completely suppressed, and the suppression lasts for long annealing times even after the complete oxidation of the SiGe layer. The above results have been related to the mechanism of oxidation of SiGe in which the Ge piles up at the SiO2/SiGe interface by producing a thin and defect-free layer with a very high concentration of Ge.

  8. Effect of a single injection of cabergoline at dry off on udder characteristics in high-yielding dairy cows.

    PubMed

    Bertulat, S; Isaka, N; de Prado, A; Lopez, A; Hetreau, T; Heuwieser, W

    2017-04-01

    In recent years, relationships between high milk yield at dry off, higher prevalence for new intramammary infections, and stress were evaluated. Considering increasing milk yield, dry off methods need to be refined to ensure udder health and animal welfare, especially in high-yielding dairy cows. The present work evaluated the effect of a single cabergoline injection (Velactis, Ceva Santé Animale, Libourne, France) at dry off on udder pressure, milk leakage, and signs of udder pain after dry off. A total of 234 high-yielding (≥16 kg of milk/d) dairy cows was enrolled 7 d before and followed up until 14 d after dry off. Cows were dried off without preparation (i.e., no feed change or intermittent milking before dry off) and treated with a single i.m. injection of 5.6 mg of cabergoline (n = 115) or placebo (n = 119) after last milking. Udder characteristics were measured 4 d before (i.e., before and after milking) and 1, 2, 3, 7, 10, and 14 d after dry off. Udder pressure was evaluated utilizing a hand-held dynamometer. Milk leakage and signs of udder pain were noted as binary variables. Whereas udder pressure baseline values after last milking did not differ between treatment groups (0.541 ± 0.15 kg), cabergoline significantly reduced udder pressure in primiparous but not in multiparous cows after dry off. Differences between cabergoline- and placebo-treated primiparous cows could be evaluated until 3 d after dry off. The first day after dry off, udder pressure in placebo- and cabergoline-treated cows increased by 115% and 42.3%, respectively. Whereas pressure values in placebo cows were highest on the first day after dry off (1.16 ± 0.61 kg) and slowly decreased afterward, udder pressure in cows treated with cabergoline had a slower increase and peak only 2 d after dry off (0.94 ± 0.44 kg). Furthermore, cabergoline caused a reduction of milk leakage, a known factor for new intramammary infections. Only 11.3% of cows treated with cabergoline showed milk

  9. Dry low NOx combustion system with pre-mixed direct-injection secondary fuel nozzle

    SciTech Connect

    Zuo, Baifang; Johnson, Thomas; Ziminsky, Willy; Khan, Abdul

    2013-12-17

    A combustion system includes a first combustion chamber and a second combustion chamber. The second combustion chamber is positioned downstream of the first combustion chamber. The combustion system also includes a pre-mixed, direct-injection secondary fuel nozzle. The pre-mixed, direct-injection secondary fuel nozzle extends through the first combustion chamber into the second combustion chamber.

  10. [Optimization of vacuum belt drying process of Gardeniae Fructus in Reduning injection by Box-Behnken design-response surface methodology].

    PubMed

    Huang, Dao-sheng; Shi, Wei; Han, Lei; Sun, Ke; Chen, Guang-bo; Wu Jian-xiong; Xu, Gui-hong; Bi, Yu-an; Wang, Zhen-zhong; Xiao, Wei

    2015-06-01

    To optimize the belt drying process conditions optimization of Gardeniae Fructus extract from Reduning injection by Box-Behnken design-response surface methodology, on the basis of single factor experiment, a three-factor and three-level Box-Behnken experimental design was employed to optimize the drying technology of Gardeniae Fructus extract from Reduning injection. With drying temperature, drying time, feeding speed as independent variables and the content of geniposide as dependent variable, the experimental data were fitted to a second order polynomial equation, establishing the mathematical relationship between the content of geniposide and respective variables. With the experimental data analyzed by Design-Expert 8. 0. 6, the optimal drying parameter was as follows: the drying temperature was 98.5 degrees C , the drying time was 89 min, the feeding speed was 99.8 r x min(-1). Three verification experiments were taked under this technology and the measured average content of geniposide was 564. 108 mg x g(-1), which was close to the model prediction: 563. 307 mg x g(-1). According to the verification test, the Gardeniae Fructus belt drying process is steady and feasible. So single factor experiments combined with response surface method (RSM) could be used to optimize the drying technology of Reduning injection Gardenia extract.

  11. Effect of trehalose on DNA integrity of freeze-dried boar sperm, fertilization, and embryo development after intracytoplasmic sperm injection.

    PubMed

    Men, Nguyen Thi; Kikuchi, Kazuhiro; Nakai, Michiko; Fukuda, Atsunori; Tanihara, Fuminori; Noguchi, Junko; Kaneko, Hiroyuki; Linh, Nguyen Viet; Nguyen, Bui Xuan; Nagai, Takashi; Tajima, Atsushi

    2013-12-01

    Freeze-drying (FD) medium containing ethylene glycol-bis(2-aminoethylether)-N,N,N',N'-tetraacetic acid (EGTA) is reported to be beneficial for maintenance of sperm DNA integrity after FD. Recently, trehalose has also been reported to have notable ability to stabilize the protein structure and biomembranes of sperm in a dry state. In this study, we examined the effect of a combination of EGTA and different concentrations of trehalose in FD medium on sperm DNA integrity and the in vitro development of IVM porcine oocytes after intracytoplasmic sperm injection (ICSI) using freeze-dried boar sperm. Ejaculated sperm from a boar were suspended in basic FD medium supplemented with 0, 3.75, 7.5, 15, 30, 60, or 90 mM trehalose and freeze-dried. After rehydration, the sperm in all groups were subjected to DNA damage detection using a Halomax kit. It was found that the level of DNA damage in 15-mM group was significantly lower than that in 0-mM group, and no difference was observed between the 15-, 7.5-, and 3.75-mM groups. Moreover, there were no significant differences in the DNA damage level among 0, 3.75 mM, and other groups treated with trehalose. When freeze-dried sperm were used for ICSI, the fertilization rates and blastocyst formation rates (observed at 10 hours and 6 days of IVC after ICSI, respectively) in the 7.5- and 15-mM groups were not different from those in 0-mM group. These results suggest that FD medium supplemented with trehalose at appropriate concentrations improves sperm DNA integrity, but does not improve fertilization and preimplantation embryo development of IVM oocytes following ICSI.

  12. Crystalline marble beats limestone for fluegas desulfurization

    SciTech Connect

    1996-05-01

    NovaCon Energy Systems, Inc. (Bedford, NY) has developed an alternative to conventional limestone sorbents. The new process uses a class of marble, selected with a proprietary model. Recent pilot- and full-scale demonstrations in pulverized-coal (PC) and circulating fluidized bed (CFB) boilers suggest that these patented sorbents outperform conventional limestone for the simultaneous control of SOx, NOx, and particulates during the combustion of coal and sulfur-rich fuels, such as oil, mixed municipal waste and used tires. Dubbed thermally active marbles (TAMs), these sorbents are chemically identical to grainy limestone (whose main constituent is calcium carbonate or calcite). However, thanks to the increased pressures and temperatures experienced during their geologic history, these metamorphic minerals have a regular crystalline structure that offers some advantages in the combustion zone. TAMs, on the other hand, enjoy better calcium-utilization rates because upon heating, they cleave along inter- and intra-crystalline faces, continuously exposing fresh surfaces. By minimizing the self-extinguishment suffered by limestone sorbents, TAMs are effective over operating temperatures from 1,200 F to 2,800 F, which is 400 F higher than other calcium-based sorbents. This allows them to be injected closer to the burner or combustion grate to maximize residence time in the unit.

  13. Field evaluation of natural gas and dry sorbent injection for MWC emissions control

    SciTech Connect

    Wohadlo, S; Abbasi, H; Cygan, D

    1993-10-01

    The Institute of Gas Technology (IGT), in cooperation with the Olmsted Waste-to-Energy Facility (OWEF) and with subcontracted engineering services from the Energy and Environmental Research Corporation (EER), has completed the detailed engineering and preparation of construction specifications for an Emissions Reduction Testing System (ERTS). The ERTS has been designed for retrofit to one of two 100-ton/day municipal waste combustors at the OWEF, located in Rochester, Minnesota. The purpose of the retrofit is to conduct a field evaluation of a combined natural gas and sorbent injection process (IGT`s METHANE de-TOX{sup SM}, IGT Patent No. 5,105,747) for reducing the emissions of oxides of nitrogen (NO{sub x}), hydrochloric acid (HCI), oxides of sulfur (SO{sub x}), carbon monoxide (CO), total hydrocarbons (THC), and chlorinated hydrocarbons (dioxin/furans). In addition, the design includes modifications for the control of heavy metals (HM). Development of the process should allow the waste-to-energy industry to meet the Federal New Source Performance Standards for these pollutants at significantly lower costs when compared to existing technology of Thermal deNO{sub x} combined with spray dryer scrubber/fabric filters. Additionally, the process should reduce boiler corrosion and increase both the thermal and power production efficiency of the facility.

  14. Controlling the injection of ammonia in a dry type exhaust gas denitration process

    SciTech Connect

    Shiraishi, Y.; Ukawa, N.

    1982-02-02

    In a first processor unit the relationship between the amount of nitrogen oxides in a combustion exhaust gas and a numerical value representing an amount of combustion, E.G. - fuel flow rate or the like, is stored. In a second processor unit the ratio of ammonia to nitrogen oxides as a function of the combustion exhaust gas temperature is stored. A numerical value corresponding to the actual measured amount of combustion is inputted to the first processor unit to derive the amount of nitrogen oxides in the combustion exhaust gas. The actual measured combustion exhaust gas temperature is inputted to the second processor unit to derive the ratio of ammonia to nitrogen oxides. The optimum amount of ammonia to be injected is derived by multiplying the amount of nitrogen oxides, derived by means of the first processor unit, by the ratio of ammonia to nitrogen oxides derived by means of the second processor unit. In a preferable embodiment of the present invention, the ratio of ammonia to nitrogen oxides is corrected before the multiplication by means of a correction factor which is stored in a third processor unit and which corresponds to a time variation rate of the combustion exhaust gas temperature.

  15. Evaluation of Dry Sorbent Injection Technology for Pre-Combustion CO{sub 2} Capture

    SciTech Connect

    Richardson, Carl; Steen, William; Triana, Eugenio; Machalek, Thomas; Davila, Jenny; Schmit, Claire; Wang, Andrew; Temple, Brian; Lu, Yongqi; Lu, Hong; Zhang, Luzheng; Ruhter, David; Rostam-Abadi, Massoud; Sayyah, Maryam; Ito, Brandon; Suslick, Kenneth

    2013-09-30

    This document summarizes the work performed on Cooperative Agreement DE-FE0000465, “Evaluation of Dry Sorbent Technology for Pre-Combustion CO{sub 2} Capture,” during the period of performance of January 1, 2010 through September 30, 2013. This project involves the development of a novel technology that combines a dry sorbent-based carbon capture process with the water-gas-shift reaction for separating CO{sub 2} from syngas. The project objectives were to model, develop, synthesize and screen sorbents for CO{sub 2} capture from gasified coal streams. The project was funded by the DOE National Energy Technology Laboratory with URS as the prime contractor. Illinois Clean Coal Institute and The University of Illinois Urbana-Champaign were project co-funders. The objectives of this project were to identify and evaluate sorbent materials and concepts that were suitable for capturing carbon dioxide (CO{sub 2}) from warm/hot water-gas-shift (WGS) systems under conditions that minimize energy penalties and provide continuous gas flow to advanced synthesis gas combustion and processing systems. Objectives included identifying and evaluating sorbents that efficiently capture CO{sub 2} from a gas stream containing CO{sub 2}, carbon monoxide (CO), and hydrogen (H{sub 2}) at temperatures as high as 650 °C and pressures of 400-600 psi. After capturing the CO{sub 2}, the sorbents would ideally be regenerated using steam, or other condensable purge vapors. Results from the adsorption and regeneration testing were used to determine an optimal design scheme for a sorbent enhanced water gas shift (SEWGS) process and evaluate the technical and economic viability of the dry sorbent approach for CO{sub 2} capture. Project work included computational modeling, which was performed to identify key sorbent properties for the SEWGS process. Thermodynamic modeling was used to identify optimal physical properties for sorbents and helped down-select from the universe of possible sorbent

  16. Influence Of Changing the Flow Rate In The Acoustic Response And Saturation During Forced Imbibition In A Limestone

    NASA Astrophysics Data System (ADS)

    Lopes, S.; Lebedev, M.; Muller, T. M.

    2012-12-01

    Forced imbibition was performed in a Limestone Savonnieres by injecting water into a dry sample. The injection was monitored with X-ray Computed Tomography (CT) and active ultrasonic measurements so that the time-space distribution of the invading fluid could be simultaneously observed in CT images and quantified through measuring P-wave velocities and water saturation. The CT scans allowed us to observe a water front advancing away from the area of injection and estimate saturation. Through the evolution of P-wave velocities, we observed that the approaching of the water front to the monitored position decreased P-wave velocities while the saturation increased continuously. Decreasing injection rate decreased P-wave velocities and saturation. Increasing injection rate, increased P-wave velocities and saturation, sharply and for a short period of time followed by a slight decrease for P-wave velocities and a continuous increase. Our experimental data confirms how sensitive acoustic waves are to the presence of water and that changing injection rates promote considerable fluid distribution that is drastically reflected in the acoustic velocities. Furthermore, the same patterns have been observed in our previous work with sandstones.; Waveforms for the P-waves picked during this experiment: before injection (blue line) and after injecting 8.4 mL of volume of water (orange line). Note the decrease of wave-amplitude and increase of wavelength. ; P-wave velocities with volume of water injected. Dashed lines represent the moments when we decreased injection rate, at 7.9 mL of volume of water injected, and when we increased injection rate at 10.7 mL. Note the immediate decrease and increase of P-wave velocity when we decrease and increase the injection rate, respectively.

  17. Scaling on a limestone flooring

    NASA Astrophysics Data System (ADS)

    Carmona-Quiroga, P. M.; Blanco-Varela, M. T.; Martínez-Ramírez, S.

    2012-04-01

    Natural stone can be use on nearly every surface, inside and outside buildings, but decay is more commonly reported from the ones exposed to outdoor aggressively conditions. This study instead, is an example of limestone weathering of uncertain origin in the interior of a residential building. The stone, used as flooring, started to exhibit loss of material in the form of scaling. These damages were observed before the building, localized in the South of Spain (Málaga), was inhabited. Moreover, according to the company the limestone satisfies the following European standards UNE-EN 1341: 2002, UNE-EN 1343: 2003; UNE-EN 12058: 2004 for floorings. Under these circumstances the main objective of this study was to assess the causes of this phenomenon. For this reason the composition of the mortar was determined and the stone was characterized from a mineralogical and petrological point of view. The last material, which is a fossiliferous limestone from Egypt with natural fissure lines, is mainly composed of calcite, being quartz, kaolinite and apatite minor phases. Moreover, under different spectroscopic and microscopic techniques (FTIR, micro-Raman, SEM-EDX, etc) samples of the weathered, taken directly from the buildings, and unweathered limestone tiles were examined and a new mineralogical phase, trona, was identified at scaled areas which are connected with the natural veins of the stone. In fact, through BSE-mapping the presence of sodium has been detected in these veins. This soluble sodium carbonate would was dissolved in the natural waters from which limestone was precipitated and would migrate with the ascendant capilar humidity and crystallized near the surface of the stone starting the scaling phenomenon which in historic masonry could be very damaging. Therefore, the weathering of the limestone would be related with the hygroscopic behaviour of this salt, but not with the constructive methods used. This makes the limestone unable to be used on restoration

  18. Effects of brine injection wells, dry holes, and plugged oil/gas wells on chloride, bromide, and barium concentrations in the Gulf Coast Aquifer, southeast Texas, USA.

    PubMed

    Hudak, P F; Wachal, D J

    2001-06-01

    Data from 1,122 brine injection wells, 24,515 dry holes, 20,877 plugged oil/gas wells, and 256 water wells were mapped with a geographic information system (GIS) and statistically analyzed. There were 9, 107, and 58 water wells within 750 m of a brine injection well, dry hole, or plugged oil/gas well, respectively. Computed median concentrations were 157 mg/l for chloride, 0.8 mg/l for bromide, and 169 microg/l for barium. The maximum chloride concentration was 2,384 mg/l, close to 10 times the secondary drinking water standard. Shallow water wells and water wells near plugged oil/gas wells had significantly higher chloride and bromide levels.

  19. LIFAC Sorbent Injection Desulfurization Demonstration Project

    SciTech Connect

    Not Available

    1992-01-01

    The LIFAC technology has similarities to other sorbent injection technologies using humidification, but employs a unique patented vertical reaction chamber located down-stream of the boiler to facilitate and control the sulfur capture and other chemical reactions. This chamber improves the overall reaction efficiency enough to allow the use of pulverized limestone rather than more expensive reagents such as lime which are often used to increase the efficiency of other sorbent injection processes. Sorbent injection is a potentially important alternative to conventional wet lime and limestone scrubbing, and this project is another effort to test alternative sorbent injection approaches. In comparison to wet systems, LIFAC, with recirculation of the sorbent, removes less sulfur dioxide - 75--85% relative to 90% or greater for conventional scrubbers - and requires more reagent material. However, if the demonstration is successful, LIFAC will offer these important advantages over wet scrubbing systems: LIFAC is relatively easy to retrofit to an existing boiler and requires less area than conventional wet FGD systems; LIFAC is less expensive to install than conventional wet FGD processes; LIFAC's overall costs measured on a dollar-per-ton S0{sub 2} removed basis are less, an important advantage in a regulatory regime with trading of emission allocations. LIFAC produces a dry, readily disposable waste by-product versus a wet product; and LIFAC is relatively simple to operate.

  20. Inductively coupled plasma mass spectrometry with a twin quadrupole instrument using laser ablation sample introduction and monodisperse dried microparticulate injection

    SciTech Connect

    Allen, Lloyd A.

    1996-10-17

    The focus of this dissertation is the use of a twin quadrupole inductively coupled plasma mass spectrometer (ICP-MS) for the simultaneous detection of two m/z values. The twin quadrupole ICP-MS is used with laser ablation sample introduction in both the steady state (10 Hz) and single pulse modes. Steady state signals are highly correlated and the majority of flicker noise cancels when the ratio is calculated. Using a copper sample, the isotope ratio 63Cu+/65Cu+ is measured with a relative standard deviation (RSD) of 0.26%. Transient signals for single laser pulses are also obtained. Copper isotope ratio measurements for several laser pulses are measured with an RSD of 0.85%. Laser ablation (LA) is used with steel samples to assess the ability of the twin quadrupole ICP-MS to eliminate flicker noise of minor components of steel samples. Isotopic and internal standard ratios are measured in the first part of this work. The isotope ratio 52Cr+/53Cr+ (Cr present at 1.31 %) can be measured with an RSD of 0.06 % to 0.1 %. For internal standard elements, RSDs improve from 1.9 % in the Cr+ signal to 0.12% for the ratio of 51V+ to 52Cr+. In the second part of this work, one mass spectrometer is scanned while the second channel measures an individual m/z value. When the ratio of these two signals is calculated, the peak shapes in the mass spectrum are improved significantly. Pulses of analyte and matrix ions from individual drops are measured simultaneously using the twin quadrupole ICP-MS with monodisperse dried microparticulate injection (MDMI). At modest Pb concentrations (500 ppm), a shoulder on the leading edge of the Li+ signal becomes apparent. Space charge effects are consistent with the disturbances seen.

  1. Structural studies in limestone sulfidation

    SciTech Connect

    Fenouil, Laurent A.

    1993-05-01

    This study investigates the sulfidation of limestone at high temperatures (700--900°C) as the first step in the design of a High-Temperature Coal-Gas Clean-Up system using millimeter-size limestone particles. Several workers have found that the rate of this reaction significantly decreases after an initial 10 to 15% conversion of CaCO3 to CaS. The present work attempts to explain this feature. It is first established that millimeter-size limestone particles do not sinter at temperatures up to the CaCO3 calcination point (899°C at 1.03 bar CO2} partial pressure). It is then shown that CaS sinters rapidly at 750 to 900°C if CO2 is present in the gas phase. Scanning Electron Microscope (SEM) photographs and Electron Dispersive Spectroscopy (EDS) data reveal that the CaS product layer sinters and forms a quasi-impermeable coating around the CaCO3 grains that greatly hinders more H2S from reaching the still unreacted parts of the stone. Moreover, most of the pores initially present within the limestone structure begin to disappear or, at least, are significantly reduced in size. From then on, subsequent conversion is limited by diffusion of H2S through the CaS layer, possibly by S2- ionic diffusion. The kinetics is then adequately described by a shrinking-core model, in which a sharp front of completely converted limestone is assumed to progress toward the center of the pellet. Finally, experimental evidence and computer simulations using simple sintering models suggest that the CaS sintering, responsible for the sharp decrease in the sulfidation rate, is surface-diffusion controlled.

  2. Theoretical approach for enhanced mass transfer effects in-duct flue gas desulfurization processes. Volume 1, Dry sorbent injection: Final report

    SciTech Connect

    Jozewicz, W.; Rochelle, G.T.

    1992-01-29

    This report presents the results of fundamental mass transfer testing for in-duct removal of SO{sub 2}. Following this initial part of an experimental program, it became clear that the amount of initial moisture on the sorbent strongly affected the extent of Ca(OH){sub 2} conversion. Novel techniques aimed at increasing sorbent utilization were investigated and are described. Major novel technique investigated and reported on here was the reaction with SO{sub 2} of sorbents with initial free moisture (damp sorbents). The duct injection process using damp solids has the following steps: preparation of sorbent as a slurry, blending of the slurry with dry recycle materials to create damp solids, injection of the solids into the duct, reaction and drying of the solids with flue gas in the duct, collection in particulate control equipment, and finally recycle of dry solids with some bleed to disposal. The moisture content of the solids at each step affects system performance. Various factors favor high moisture whereas others favor low moisture. (VC)

  3. Pilot-scale limestone emission control (LEC) process: A development project. Volume 1: Main report and appendices A, B, C, and D. Final report

    SciTech Connect

    Not Available

    1994-03-01

    ETS, Inc., a pollution consulting firm with headquarters in Roanoke, Virginia, has developed a dry, limestone-based flue gas desulfurization (FGD) system. This SO{sub 2} removal system, called Limestone Emission Control (LEC), can be designed for installation on either new or existing coal-fired boilers. In the LEC process, the SO{sub 2} in the flue gas reacts with wetted granular limestone that is contained in a moving bed. A surface layer of principally calcium sulfate (CaSO{sub 4}) is formed on the limestone. Periodic removal of this surface layer by mechanical agitation allows high utilization of the limestone granules. The primary goal of the current study is the demonstration of the techno/economic capability of the LEC system as a post-combustion FGD process capable of use in both existing and future coal-fired boiler facilities burning high-sulfur coal. A nominal 5,000 acfm LEC pilot plant has been designed, fabricated and installed on the slipstream of a 70,000 pph stoker boiler providing steam to Ohio University`s Athens, Ohio campus. The pilot plant was normally operated on the slipstream of the Ohio Univ. boiler plant flue gas, but also had the capability of operating at higher inlet SO{sub 2} concentrations (typically equivalent to 3-1/2% sulfur coal) than those normally available from the flue gas slipstream. This was accomplished by injecting SO{sub 2} gas into the slipstream inlet. The pilot plant was instrumented to provide around-the-clock operation and was fully outfitted with temperature, SO{sub 2}, gas flow and pressure drop monitors.

  4. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially (not less than 94 percent) of calcium carbonate (CaCO3) and is prepared by the crushing, grinding,...

  5. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially (not less than 94 percent) of calcium carbonate (CaCO3) and is prepared by the crushing, grinding,...

  6. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially (not less than 94 percent) of calcium carbonate (CaCO3) and is prepared by the crushing, grinding,...

  7. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 3 2014-04-01 2014-04-01 false Ground limestone. 184.1409 Section 184.1409 Food... GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially (not less than 94 percent) of calcium carbonate (CaCO3) and is prepared by the crushing, grinding, and classifying of...

  8. 21 CFR 184.1409 - Ground limestone.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ground limestone. 184.1409 Section 184.1409 Food... Specific Substances Affirmed as GRAS § 184.1409 Ground limestone. (a) Ground limestone consists essentially (not less than 94 percent) of calcium carbonate (CaCO3) and is prepared by the crushing, grinding,...

  9. CALCIUM CARBONATE DISSOLUTION RATE IN LIMESTONE CONTACTORS

    EPA Science Inventory

    The rate of carbonate mineral dissolution from limestone was studied using a rotating disk apparatus and samples of limestone of varied composition. The purpose of this study was to determine the effect of limestone composition on the kinetics of carbonate mineral dissolution. Th...

  10. Investigation and demonstration of dry carbon-based sorbent injection for mercury control. Quarterly technical report, July 1, 1996--September 31, 1996

    SciTech Connect

    Hunt, T.; Sjostrom, S.; Smith, J.

    1996-11-06

    The overall objective of this two phase program is to investigate the use of dry carbon-based sorbents for mercury control. This information is important to the utility industry in anticipation of pending regulations. During Phase I, a bench-scale field test device that can be configured as an electrostatic precipitator, a pulse-jet baghouse, or a reverse-gas baghouse has been designed, built and integrated with an existing pilot-scale facility at PSCo`s Comanche Station. Up to three candidate sorbents will be injected into the flue gas stream upstream of the test device to and mercury concentration measurements will be made to determine the mercury removal efficiency for each sorbent. During the Phase II effort, component integration for the most promising dry sorbent technology shall be tested at the 5000 acfm pilot-scale.

  11. Investigation and demonstration of dry carbon-based sorbent injection for mercury control. Quarterly report, November 1, 1995--December 31, 1995

    SciTech Connect

    Hunt, T.; Sjostrom, S.

    1996-02-05

    The overall objective to this two phase program is to investigate dry carbon-based sorbents for mercury control. During Phase I, a bench-scale field test device that can simulate an electrostatic precipitator, a pulse-jet baghouse, or a reverse-gas baghouse will be designed and integrated with an existing pilot-scale facility at Public Service Company of Colorado`s (PSCo`s) Comanche station. Various sorbents will then be injected to determine the mercury removal efficiency for each. During Phase II effort, component integration of the most promising technologies shall be tested at the 5000 acfm pilot-scale. The primary task currently underway is the facility design. The design is expected to be finished in January, 1996. The facility, regardless of the particulate control module configuration, will be fitted with supply line injection port, through which mercury sorbents and SO{sub 2} control sorbents can be added to the flue gas stream.

  12. Water transport in limestone by X-ray CAT scanning

    USGS Publications Warehouse

    Mossoti, Victor G.; Castanier, Louis M.

    1989-01-01

    The transport of water through the interior of Salem limestone test briquettes can be dynamically monitored by computer aided tomography (commonly called CAT scanning in medical diagnostics). Most significantly, unless evaporation from a particular face of the briquette is accelerated by forced air flow (wind simulation), the distribution of water in the interior of the briquette remains more or less uniform throughout the complete drying cycle. Moreover, simulated solar illumination of the test briquette does not result in the production of significant water gradients in the briquette under steady-state drying conditions.

  13. Fracture Decoupling of Small Chemical Explosions in Granite and Limestone

    NASA Astrophysics Data System (ADS)

    Stroujkova, A. F.; Bonner, J. L.; Reinke, R.; Lenox, E. A.

    2012-12-01

    Reduction of the seismic amplitudes produced by underground explosions due to dissipation in a low-coupling medium poses a significant challenge for nuclear test monitoring. We examined the data from two experiments, which involved conducting explosions in the damage zone created by previous explosions ("repeat shots"). The first experiment was conducted in central New Hampshire in a fluid saturated granodiorite. The experiment involved detonating two 46 kg explosions: one in virgin rock and the other in the fractured rock zone produced by a larger (232 kg) explosion. The second experiment took place near Albuquerque, NM, in dry limestone. In this scenario the second explosion was conducted in the cavity created by the first explosion. Both limestone explosions had yields of 90.5 kg. The reduction of the seismic amplitudes was observed for both repeat shots: in granodiorite the amplitudes were reduced by a factor of 2-3, in limestone by a factor of 3-4 compared to the shots in the undamaged rocks. For the granodiorite repeat shot the decoupling ratios were frequency dependent with stronger amplitude reduction at higher frequencies. In addition, the virgin rock shot produced higher corner frequency and overshoot parameter than the repeat shot. For the limestone shot the decoupling ratios were nearly flat at all frequencies with similar corner frequencies. This observation suggests different mechanisms of energy dissipation for the two experiments.

  14. LIFAC Sorbent Injection Desulfurization Demonstration Project

    SciTech Connect

    Not Available

    1992-01-01

    Sorbent injection is a potentially important alternative to conventional wet lime and limestone scrubbing, and this project is another effort to test alternative sorbent injection approaches. In comparison to wet systems, LIFAC, with recirculation of the sorbent, removes less sulfur dioxide - 75--85% relative to 90% or greater for conventional scrubbers -- and requires more reagent material. However, if the demonstration is wet scrubbing systems: LIFAC is relatively easy to retrofit to an existing boiler and requires less area than conventional wet FGD systems. LIFAC is less expensive to install than conventional wet FGD processes. LIFAC's overall costs measured on a dollar-per-ton SO[sub 2] removed basis are less, an important advantage in a regulatory regime with trading of emission allocations. LIFAC produces a dry, readily disposable waste by-product versus a wet product. LIFAC is relatively simple to operate.

  15. Whole rolled sunflower seeds with or without additional limestone in lactating dairy cattle rations.

    PubMed

    Finn, A M; Clark, A K; Drackley, J K; Schingoethe, D J; Sahlu, T

    1985-04-01

    Thirty lactating Holstein cows were in a continuous trial from 21 to 120 days postpartum to evaluate diets containing whole, rolled sunflower seeds with or without additional limestone. Cows were fed individually total mixed rations of (dry matter) 47% corn silage, 9% alfalfa hay, and 44% concentrate. Concentrates were corn and soybean meal (control); corn, soybean meal, and 22% sunflower seeds; or corn, soybean meal, and sunflower seeds plus 3.5% additional limestone. Milk yield (32.2, 32.0, and 32.8 kg/day) was similar among rations. Yield of 4% fat-corrected milk was lower for cows fed sunflower seeds without additional limestone (30.2, 28.1, and 30.2 kg/day) because of lower milk fat percentages (3.57, 3.19, and 3.51). Milk protein percentage tended to be lower for cows fed sunflower seeds with additional limestone (3.01, 2.97, and 2.90). Milk, flavor score was acceptable but tended to be lower for milk from cows fed sunflower seeds with additional limestone (8.4, 8.5, and 7.9). Milk fat from cows fed sunflower seed rations contained less carbon-14:0, 16:0, and 16:1 fatty acids but more carbon-18:0. Dry matter intakes were 21.0, 18.4, and 20.0 kg/day. Dry matter digestibilities, body weight changes, and ruminal volatile fatty acid concentrations were similar among treatments. Total cholesterol in blood serum was elevated in cows fed sunflower seed rations. Insoluble salts of fatty acids were increased in ruminal fluid dry matter from cows fed sunflower seeds but were not increased further by additional limestone. Concentrations of nonesterified carbon-18:1 fatty acids in ruminal fluid dry matter were lower for cows fed sunflower seeds with additional limestone.

  16. Investigation and demonstration of dry carbon-based sorbent injection for mercury control. Quarterly technical report, April 1--June 30, 1996

    SciTech Connect

    Hunt, T.; Sjostrom, S.; Smith, J.; Chang, R.

    1996-07-27

    The overall objective this two phase program is to investigate the use of dry carbon-based sorbents for mercury control. During Phase 1, a bench-scale field test device that can be configured as an electrostatic precipitator, a pulse-jet baghouse, or a reverse-gas baghouse has been designed and will be integrated with an existing pilot-scale facility at PSCo`s Comanche Station. Up to three candidate sorbents will then be injected into the flue gas stream upstream of the test device to determine the mercury removal efficiency for each sorbent. During the Phase 11 effort, component integration for the most promising dry sorbent technology (technically and economically feasible) shall be tested at the 5000 acfm pilot-scale. An extensive work plan has been developed for the project. Three sorbents will be selected for evaluation at the facility through investigation, presentation, and discussion among team members: PSCO, EPRI, ADA, and DOE. The selected sorbents will be tested in the five primary bench-scale configurations: pulse `et baghouse, TOXECON, reverse-gas baghouse, electrostatic precipitator, and an ESP or fabric filter `with no Comanche ash in the flue gas stream. In the EPRI TOXECON system, mercury sorbents will be injected downstream of a primary particulate control device, and collected in a pulse-jet baghouse operated at air-to-cloth ratios of 12 to 16 ft/min, thus separating the mercury and sorbent from the captured flyash. In the no-ash configuration, an external flyash sample will be injected into a clean gas stream to investigate possible variations in sorbent effectiveness in the presence of different ashes. The use of an existing test facility, a versatile design for the test fixture, and installation of a continuous mercury analyzer will allow for the completion of this ambitious test plan. The primary activity during the quarter was to complete fabrication and installation of the facility.

  17. Laboratory Particle Velocity Experiments on Indiana Limestone and Sierra White Granite

    DTIC Science & Technology

    1991-10-01

    resemble the pulses generated in Sierra White granite. 27 25o 2. 20 Dry ( Test 598) 20 --- .... Saturated (Test 601) .............. Saturated/Frozen (Test...ps, which is about the same as the wave speed in Sierra White granite. 29 15 0 .........i ......... Dry ( Test 598) - Saturated (Test 601) 120...Comparison of displacement histories at 30-mm range in Indiana limestone (16% porosity) for three different pore conditions. 30 10 Dry ( Test 598

  18. Experimental investigation of high-temperature, short residence-time calcination and sulfation of limestone and dolostone sorbents

    SciTech Connect

    Hu, Naiya; Miller, S.F.; Scaroni, A.W.

    1994-12-31

    Sulfur dioxide emissions from coal-fired utility boilers and furnaces continue to be of significant regulatory concern. One approach to reducing these emissions that has received considerable attention is the injection of dry, pulverized sorbent (limestone or dolostone) into the combustion chamber. This technology has been applied to conventional coal-fired utility boilers and is considered to be a good candidate for use in coal-fired heat engine applications. During the process, the injected limestone or dolostone particles are rapidly heated by the hot combustion gases and calcined by the reactions CaCO{sub 3} {yields} CaO + CO{sub 2} and CaMg(CO{sub 3}){sub 2} {yields} CaO + MgO + 2CO{sub 2}, respectively. The CaO produced then reacts with SO{sub 2} and excess O{sub 2} in the combustion gases to form CaSO{sub 4}. Experimental data on the rates of calcination, sintering and sulfation have been reported by Borgwardt and others. The physical structure of the calcined sorbents has also been investigated and a number of models have been developed describing the calcination and sulfation processes. The primary application of dry sorbent injection is to conventional coal-fired utility boilers. The sorbent particle size used is either small (in the range of 1 to 30 {mu}m) in pulverized coal applications or large (in the range of 0.25 to 1 mm) for fluidized-bed applications. Few investigations have been carried out using 30 to 100 {mu}m particles, which is the size range of interest for coal-fired heat engine applications. This study investigated the calcination and sulfation behavior of three different sorbents (two limestones and one dolostone) in the size range from 37 to 105 {mu}m. The time required for heating and calcination, the effect of the calcination process on sulfation behavior, and the effect of sorbent type on sulfation behavior were of primary interest.

  19. On the failure mode in dry and hygrothermally aged short fiber-reinforced injection-molded polyarylamide composites by acoustic emission

    NASA Astrophysics Data System (ADS)

    Czigány, T.; Mohd Ishak, Z. A.; Karger-Kocsis, J.

    1995-09-01

    The failure mode in injection-molded short glass (GF) and carbon fiber (CF) reinforced polyarylamide (PAR) composites was studied on compact tension (CT) specimens in as-received (AR), hygrothermally aged (HA) and re-dried (RD) states, respectively, using acoustic emission (AE) and fractography. A significant difference was revealed in the failure manner characterized by the cumulative run, amplitude and energy distribution of the AE events as a function of the water content of the composites. Furthermore, a correlation was found between the cumulative AE events up to the maximum load and the fracture toughness of the composites. It was shown that the fracture response and thus the failure behavior of the water-saturated PAR composites can be restored by drying. This fact indicates that the water absorption and desorption are of a purely physical nature, i.e. they are reversible processes. It was established that chopped fiber-reinforced PAR composites fail by matrix deformation along with fiber/matrix debonding in the crack initiation, whereas fiber pull-out becomes dominant in the crack propagation range. Water uptake shifts both the AE amplitude and energy curves toward lower values, a phenomenon attributed to plastification of the PAR matrix by water.

  20. Rapid and sensitive solid phase extraction-large volume injection-gas chromatography for the analysis of mineral oil saturated and aromatic hydrocarbons in cardboard and dried foods.

    PubMed

    Moret, Sabrina; Barp, Laura; Purcaro, Giorgia; Conte, Lanfranco S

    2012-06-22

    A rapid off-line solid phase extraction-large volume injection-gas chromatography-flame ionisation detection (SPE-LVI-GC-FID) method, based on the use of silver silica gel and low solvent consumption, was developed for mineral oil saturated hydrocarbon (MOSH) and mineral oil aromatic hydrocarbon (MOAH) determination in cardboard and dried foods packaged in cardboard. The SPE method was validated using LVI with a conventional on-column injector and the retention gap technique (which allowed to inject up to 50 μL of the sample). Detector response was linear over all the concentration range tested (0.5-250 μg/mL), recoveries were practically quantitative, repeatability was good (coefficients of variation lower than 7%) and limit of quantification adequate to quantify the envisioned limit of 0.15 mg/kg proposed in Germany for MOAH analysis in food samples packaged in recycled cardboard. Rapid heating of the GC oven allowed to increase sample throughput (3-4 samples per hour) and to enhance sensitivity. The proposed method was used for MOSH and MOAH determination in selected food samples usually commercialised in cardboard packaging. The most contaminated was a tea sample (102.2 and 7.9 mg/kg of MOSH and MOAH below n-C25, respectively), followed by a rice and a sugar powder sample, all packaged in recycled cardboard.

  1. Sodium-limestone double alkali flue gas desulfurization process with improved limestone utilization

    SciTech Connect

    Biolchini, R.J.; Boward, W.L. Jr.; Wang, K.H.

    1987-08-18

    This patent describes a sodium-limestone double alkali process for the continuous desulfurization of flue gas, having the steps of absorbing sulfur dioxide from an SO/sub 2/-containing gas stream in an absorber with an aqueous solution of sodium sulfite and sodium bisulfite, diverting at least a portion of the absorber effluent solution for regeneration with limestone, introducing limestone into the diverted absorber effluent solution to convert bisulfite to sulfite, separating by-product solids from the limestone-treated solution, and returning regenerated solution to the absorber, the improvement for increasing the utilization of the limestone used during the regeneration operation.

  2. Magnetic hysteresis of limestones: facies control?

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham J.; Chow, Nancy; Werner, Tomasz

    1993-03-01

    The hysteresis properties of 116 non-red, marine limestones from 92 localities indicate that remanence is carried by magnetite of pseudo-single-domain (PSD) and small multidomain (MD) size. Pelagic limestones have paramagnetic matrices and hysteresis properties compatible with larger PSD or MD grain sizes of magnetite, probably associated with detrital clay minerals introduced by pelagic rain-out. Thus they may be less suitable recorders of stable remanence. Other limestone facies (excepting dolomitized examples) have diamagnetic matrices. They include shallow—subtidal limestones which tend to have smaller PSD sizes of magnetite, as do backreef—lagoonal, undifferentiated-shelf and reef facies. It is believed that the wide geographical and temporal range of samples minimizes effects related to post-compaction groundwater flow (late diagenesis) and that the associations recognized should be tested in future studies.

  3. The behavior limestone under explosive load

    NASA Astrophysics Data System (ADS)

    Orlov, M. Yu; Orlova, Yu N.; Bogomolov, G. N.

    2016-11-01

    Limestone behavior under explosive loading was investigated. The behavior of the limestone by the action of the three types of explosives, including granular, ammonite and emulsion explosives was studied in detail. The shape and diameter of the explosion craters were obtained. The observed fragments after the blast have been classified as large, medium and small fragments. Three full-scale experiments were carried out. The research results can be used as a qualitative test for the approbation of numerical methods.

  4. [Limestone and pyrite-limestone constructed wetlands for treating river water].

    PubMed

    Zhang, Jing; Li, Rui-hua; Li, Jie; Hu, Jun-song; Sun, Qian-qian

    2013-09-01

    Polluted river water was treated with limestone and pyrite-limestone subsurface horizontal constructed wetlands. The aims were to know the performance of two wetlands on removal of common pollutants, especially nitrogen and phosphorus, and analyze the actions of these minerals. The relationship between hydraulic retention time and purification performance of two constructed wetlands was studied. The optimal hydraulic retention time for pollutant removal was about 3 d, The average removal efficiency of COD, TN and TP were 51%, 70% and 95%, respectively. With same influent and hydraulic loading, the average removal efficiency of COD, NH4+ -N, TN and TP were 53.93%, 82.13%, 66%, 50.9%, and 51.66%, 77.43%, 72.06%, 97.35% for limestone and pyrite-limestone constructed wetlands, respectively. There were few differences between limestone and pyrite-limestone wetlands on COD removal, but the nitrogen and phosphorus removal of pyrite-limestone constructed wetland was higher than that of limestone constructed wetland. The phosphorus removal of pyrite-limestone wetland was more efficiency and stable, not affected by temperature.

  5. Water resources of the Edwards limestone in the San Antonio area, Texas

    USGS Publications Warehouse

    Livingston, Penn; Sayre, A.N.; White, W.N.

    1936-01-01

    The water enters the limestone in a zone of outcrop along the Balcones escarpment, which crosses the northern parts of Bexar and Medina Counties and extends a long distance both to the east and west of these counties. It is estimated that the combined annual losses into the limestone from the Medina, Prio, Dry Prio, Nueces, and Sabinal Rivers and Hondo Creek may average as much as 150,000 acre-feet a year, the equivalent of a continuous flow of about 134,000,000 gallons a day. Smaller streams also contribute to the underground reservoir, and additional recharge is provided from rainfall on the outcrop of the limestone by direct penetration and by seepage from innumerable storm-water channels.

  6. Colour changes by laser irradiation of reddish building limestones

    NASA Astrophysics Data System (ADS)

    Grossi, C. M.; Benavente, D.

    2016-10-01

    We have used X-ray photoelectron spectroscopy (XPS) as a novel method to investigate the causes of colour changes in a reddish limestone under irradiation by a Q-switched Nd:YAG 1064 nm laser. We irradiated clean dry and wet surfaces of Pidramuelle Roja, a building stone frequently used in the Asturian heritage, at fluences ranging from 0.12 to 1.47 J cm-2. We measured the colour coordinates and undertook XPS analysis of the state of oxidation of iron both before and after irradiation. Visible colour changes and potential aesthetic damage occurred on dry surfaces from a fluence of 0.31 J cm-2, with the stone showing a greening effect and very intense darkening. The colour change on dry surfaces was considerably higher than on wet surfaces, which at the highest fluence (1.47 J cm-2) was also above the human visual detection threshold. The use of XPS demonstrated that the change in colour (chroma and hue) is associated with a reduction in the iron oxidation state on dry surfaces during laser irradiation. This points out to a potential routinary use of XPS to analyse causes of colour changes during laser cleaning in other types of coloured building stones.

  7. Forest seasonality shapes diet of limestone-living rhesus macaques at Nonggang, China.

    PubMed

    Tang, Chuangbin; Huang, Libin; Huang, Zhonghao; Krzton, Ali; Lu, Changhu; Zhou, Qihai

    2016-01-01

    Limestone forests are an unusual habitat for primates, but little information is available for the genus Macaca in such habitats, making a comparative understanding of extant limestone primates' behavioral adaptation incomplete. We collected data on the diet of rhesus macaques (Macaca mulatta) in a limestone habitat at Nonggang Nature Reserve, southwestern Guangxi, China, and examined the effects of forest seasonality on their diet. Our results indicated that a total of 114 species of plants are consumed by macaques. Young leaves are a preferred food, accounting for 48.9 and 56.9% of the overall diets. One group significantly increased young leaf consumption in response to availability. Fruits contributed to only 27.3 and 28.7% of overall diet. The macaque diet varied according to season. They fed on more fruits in the rainy season. Consumption of mature leaves increased when the availability of young leaves and fruits declined in the dry season, indicating that mature leaves are a fallback food for macaques in a limestone habitat. Similar to sympatric Assamese macaques, Bonia saxatilis, a shrubby, karst-endemic bamboo was consumed by rhesus macaques throughout the year, and was the top food species through most of the year, suggesting that bamboo consumption represents a key factor in the macaque's dietary adaptation to limestone habitat.

  8. GPR investigations in galleries buried inside a karstified limestone formation

    NASA Astrophysics Data System (ADS)

    Rousset, D.; Sénéchal, G.; Gaffet, S.

    2009-04-01

    A large scientific program of geophysical investigations is presently performed inside the Low-Noise Underground Laboratory (Laboratoire Souterrain à Bas Bruit / LSBB, Rustrel, France) which is an decomissioned underground missile control center, buried in a karstified limestone formation. One of the goals of this project is the understanding of the water circulation inside the structure. This experimental site offers a unique opportunity of perfoming measurements within an unweathered limestone massif. The tunnel has been dug in lower cretaceous limestone which is characterized by a low clay content, high electrical resistivity. The dip is around 25 degrees and vertical faults locally affect the structure. The studied zone is located in south-eastern France (Provence) and is characterized by a mediterranean climate with long dry periods and strong, short events of rain. This phenomenon induces large variations of water content within the karstified limestone from dry to saturated conditions. Analysis of the spatial and temporal variations of the water flow in a karstified limestones needs to define the geological context and the adequate geophysical methods. GPR offers a good tradeoff between resolution and ease of use on one hand and investigation depth on the other hand. We present some GPR profiles which have been acquired in April 2008 after a quite long and strong period of rain, inducing a complete water saturation inside the karstified massif. We used several RAMAC shielded antennas from 100 to 500 MHz. The longest profile is around 600 m long, with a 20 cm spacing, running from a raw to a concrete gallery. These data sets are characterized by a very good signal to noise ratio and a signal penetration, up to 18 meters. Signal processing includes very low frequency filtering, amplitude compensation, keeping lateral relative attenuation and ringing suppression. Final sections includes migration and time to depth conversion or depth migration. The estimated

  9. Laser Removal of Protective Treatments on Limestone

    NASA Astrophysics Data System (ADS)

    Gómez-Heras, M.; Rebollar, E.; Alvarez de Buergo, M.; Oujja, M.; Fort, R.; Castillejo, M.

    This work presents an investigation of the laser removal of polymeric materials acting as consolidants and water-repellents on limestone used on buildings of architectural and artistic value. The removal of the consolidant Paraloid B-72 and the water-repellent product Tegosivin HL-100, applied on samples of Colmenarand Bateig limestone, was studied as a function of the laser wavelength, by using the four harmonics of a Q-switched Nd:YAG laser (1064, 532, 355 and 266 nm). Elimination of the coatings and subsequent surface modifications were monitored through colorimetry, roughness measurements and scanning electron microscopy (SEM). The fundamental laser radiation was effective in removing the treatments, although thermal alteration processes were induced on the calcite crystals of the limestone. The best results were obtained by irradiation in the near UV at 355 nm.

  10. Diagenetic cements in transgressive and regressive limestone members on the Stanton Limestone (Upper Pennsylvanian), northern midcontinent

    SciTech Connect

    Xiong, Bin; Heckel, P.H.; Gonzalez, L.A. . Dept. of Geology)

    1992-01-01

    Detailed cathodoluminescent microscopy reveals various types and phases of cement growth preserved in the two limestone members of the Stanton Limestone, which represents a complete cycle of sea level rise and fall during deposition. In the transgressive Captain Creek Limestone Member, early cements are mainly isopachous rims within brachiopods. In the regressive Stoner Limestone Member, early cements are both intergranula rand intragranular isopachous rims in oolitic and skeletal grainstones and in wackestones, as well as non-luminescent syntaxial overgrowths around echinoderm grains. The second phase of cementation in both members consists of luminescence void-filling blocky calcite and syntaxial overgrowths. The latest phase of cementation in both members comprises non-luminescent void-filling and/or replacement ferroan dolomite formed during burial. The early cements are more enriched in Fe and more enriched in Mg than in Sr. However, there seems to be little difference in trace elemental compositions between the transgressive and regressive limestones in general, although certain types of cements confined to one member fall into a relatively small field. The blocky calcites exhibit much higher Fe and Mn content than the early cements. The ferroan dolomite exhibits higher Fe and Mn concentration in the transgressive than in the regressive limestone. The greater abundance of marine cements in the regressive limestone is attributed to greater residence time in high-energy warm marine environments. Differences in Fe and Mn concentration between transgressive and regressive limestone cements are attributed to differences in redox conditions of diagenetic fluids controlled by the offshore Eudora Shale separating these two limestones.

  11. LIFAC Sorbent Injection Desulfurization Demonstration Project. Quarterly report No. 6, January--March 1992

    SciTech Connect

    Not Available

    1992-09-01

    The LIFAC technology has similarities to other sorbent injection technologies using humidification, but employs a unique patented vertical reaction chamber located down-stream of the boiler to facilitate and control the sulfur capture and other chemical reactions. This chamber improves the overall reaction efficiency enough to allow the use of pulverized limestone rather than more expensive reagents such as lime which are often used to increase the efficiency of other sorbent injection processes. Sorbent injection is a potentially important alternative to conventional wet lime and limestone scrubbing, and this project is another effort to test alternative sorbent injection approaches. In comparison to wet systems, LIFAC, with recirculation of the sorbent, removes less sulfur dioxide - 75--85% relative to 90% or greater for conventional scrubbers - and requires more reagent material. However, if the demonstration is successful, LIFAC will offer these important advantages over wet scrubbing systems: LIFAC is relatively easy to retrofit to an existing boiler and requires less area than conventional wet FGD systems; LIFAC is less expensive to install than conventional wet FGD processes; LIFAC`s overall costs measured on a dollar-per-ton S0{sub 2} removed basis are less, an important advantage in a regulatory regime with trading of emission allocations. LIFAC produces a dry, readily disposable waste by-product versus a wet product; and LIFAC is relatively simple to operate.

  12. SLAM: a sodium-limestone concrete ablation model

    SciTech Connect

    Suo-Anttila, A.J.

    1983-12-01

    SLAM is a three-region model, containing a pool (sodium and reaction debris) region, a dry (boundary layer and dehydrated concrete) region, and a wet (hydrated concrete) region. The model includes a solution to the mass, momentum, and energy equations in each region. A chemical kinetics model is included to provide heat sources due to chemical reactions between the sodium and the concrete. Both isolated model as well as integrated whole code evaluations have been made with good results. The chemical kinetics and water migration models were evaluated separately, with good results. Several small and large-scale sodium limestone concrete experiments were simulated with reasonable agreement between SLAM and the experimental results. The SLAM code was applied to investigate the effects of mixing, pool temperature, pool depth and fluidization. All these phenomena were found to be of significance in the predicted response of the sodium concrete interaction. Pool fluidization is predicted to be the most important variable in large scale interactions.

  13. Fly ash disposal in a limestone quarry

    SciTech Connect

    Peffer, J.R.

    1982-05-01

    Approximately 740 000 tons of eastern bituminous coal fly ash were deposited at the abandoned Zullinger limestone quarry from 1973-1980. The quarry extended below the water table and was not lined to isolate the ash from the aquifer. Long-term groundwater pollution has apparently not resulted.

  14. CO2 mitigation via accelerated limestone weathering

    USGS Publications Warehouse

    Rau, Greg H.; Knauss, Kevin G.; Langer, William H.; Caldeira,

    2004-01-01

    We evaluate accelerated weathering of limestone (AWL: CO2 + CaCO3 + H2O=> Ca2+ + 2HCO3-) as a low-tech, inexpensive, high-capacity, environmentally-friendly CO2 capture and sequestration technology. With access to seawater and limestone being essential to this approach, significant limestone resources are close to most CO2-emitting power plants along the coastal US. Waste fines, representing more than 20% of current US crushed limestone production (>109 tonnes/yr), could be used as an inexpensive source of AWL carbonate. Under such circumstances CO2 mitigation cost could be as low as $3-$4/tonne. More broadly, 10-20% of US point-source CO2 emissions could be treated at $20-$30/tonne CO2. AWL end-solution disposal in the ocean would significantly reduce effects on ocean pH and carbonate chemistry relative to those caused by direct atmospheric or ocean CO2 disposal. Indeed, the increase in ocean Ca2+ and bicarbonate offered by AWL should enhance growth of corals and other calcifying marine organisms.

  15. Dry Mouth

    MedlinePlus

    ... of this page please turn Javascript on. Dry Mouth What Is Dry Mouth? Dry mouth is the feeling that there is ... when a person has dry mouth. How Dry Mouth Feels Dry mouth can be uncomfortable. Some people ...

  16. Dissolution-induced preferential flow in a limestone fracture.

    PubMed

    Liu, Jishan; Polak, Amir; Elsworth, Derek; Grader, Avrami

    2005-06-01

    Flow in a rock fracture is surprisingly sensitive to the evolution of flow paths that develop as a result of dissolution. Net dissolution may either increase or decrease permeability uniformly within the fracture, or may form a preferential flow path through which most of the injected fluid flows, depending on the prevailing ambient mechanical and chemical conditions. A flow-through test was completed on an artificial fracture in limestone at room temperature under ambient confining stress of 3.5 MPa. The sample was sequentially circulated by water of two different compositions through the 1500 h duration of the experiment; the first 935 h by tap groundwater, followed by 555 h of distilled water. Measurements of differential pressures between the inlet and the outlet, fluid and dissolved mass fluxes, and concurrent X-ray CT imaging and sectioning were used to characterize the evolution of flow paths within the limestone fracture. During the initial circulation of groundwater, the differential pressure increased almost threefold, and was interpreted as a net reduction in permeability as the contacting asperities across the fracture are removed, and the fracture closes. With the circulation of distilled water, permeability initially reduces threefold, and ultimately increases by two orders of magnitude. This spontaneous switch from net decrease in permeability, to net increase occurred with no change in flow rate or applied effective stress, and is attributed to the evolving localization of flow path as evidenced by CT images. Based on the X-ray CT characterizations, a flow path-dependent flow model was developed to simulate the evolution of flow paths within the fracture and its influence on the overall flow behaviors of the injected fluid in the fracture.

  17. Mineralogical characterization of the Shelburne marble and the Salem limestone

    SciTech Connect

    McGee, E.S.

    1989-01-01

    Samples of Shelburne marble and Salem limestone were selected to represent marbles and limestones used in buildings and monuments. The Royal variety of Shelburne marble is a white marble predominantly composed of calcite but has heterogeneously distributed gray inclusions. The select buff Salem limestone is a beige, homogeneous, fossiliferous limestone, predominantly composed of fragments of echinoderms and bryozoans. The author reports that both samples are appropriate test stones for the National Acid Precipitation Assessment Program stone exposure studies.

  18. Physicochemical characterizations of limestone for fluidized-bed coal combustion

    SciTech Connect

    Fuller, E.L. Jr.; Yoos, T.R. III; Walia, D.S.

    1981-05-01

    This study is an investigation of the physicochemical characteristics of three limestone samples, Quincy limestone (-20 + 60), Franklin limestone (-12 + 30), and Franklin limestone (-6 + 16), currently being tested at Oak Ridge National Laboratory for use in a fluidized-bed coal combustion unit. By correlating the chemistry, mineralogy, and surface area of these samples with empirical data obtained at Argonne National Laboratory, the sulfur capture ability and performance of these limestones can be loosely predicted. X-ray fluorescence and neutron activation analysis revealed a very high calcium content and very low concentrations of other elements in the three samples. X-ray diffraction patterns and petrographic examination of the limestone grains detected essentially no dolomite in the Quincy limestone or the fine Franklin limestone samples. The coarse Franklin limestone sample showed dolomite to be present in varying amounts up to maximum of 2.75%. Limited surface chemistry investigations of the samples were undertaken. Limestone and dolostone resources of the Tennessee Valley Authority region are widespread and abundant, and judged sufficient to meet industrial demand for many years. No problems are anticipated in securing limestone or dolostone supplies for a commercial fluidized-bed combustion plant in the Tennessee Valley Authority region. Transportation facilities and costs for limestone or dolostone will influence the siting of such a commercial fluidized-bed combustion plant. The most promising location in the Tennessee Valley Authority region at this time is Paducah, Kentucky.

  19. Limestone treatment for sulfur dioxide removal. (Latest citations from the EI compendex*plus database). Published Search

    SciTech Connect

    1998-02-01

    The bibliography contains citations concerning the use of limestone for the control of sulfur dioxide emmisions in flue gases. The various designs for flue gas desulfurization are discussed, including dry fluidized beds and wet scrubbers. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  20. Limestone reaction in calcium aluminate cement–calcium sulfate systems

    SciTech Connect

    Bizzozero, Julien Scrivener, Karen L.

    2015-10-15

    This paper reports a study of ternary blends composed of calcium aluminate cement, calcium sulfate hemihydrate and limestone. Compressive strength tests and hydration kinetics were studied as a function of limestone and calcium sulfate content. The phase evolution and the total porosity were followed and compared to thermodynamic simulation to understand the reactions involved and the effect of limestone on these binders. The reaction of limestone leads to the formation of hemicarboaluminate and monocarboaluminate. Increasing the ratio between sulfate and aluminate decreases the extent of limestone reaction.

  1. EPA compares lime, limestone FGD systems

    SciTech Connect

    Not Available

    1984-05-28

    According to a recent report by the EPA, flue gas desulfurization processes using lime require lower capital investments than limestone processes, and at low coal sulfur contents, annual revenue requirements are also lower. But this advantage disappears when coal sulfur content rises above 2%. A study of FGD systems performed by TVA evaluated absorber types, forced oxidation and the use of additives. The study compared processes with forced oxidation and landfill disposal, and found these have lower capital investments than processes without forced oxidation using pond disposal. Using additives in the limestone processes reduces both capital investment and annual revenue requirements. Adipic acid seems more efficient than MgO. Comparing absorber types, EPA found that for all systems, the TCA process was lowest in capital investment and annual revenue requirements.

  2. Limestone-gypsum flue gas desulfurization process

    SciTech Connect

    Kuroda, H.; Hashimoto, T.; Kanda, O.; Nishimura, M.; Nishimura, T.; Nozawa, S.

    1984-12-11

    A flue gas desulfurization process capable of producing a high purity gypsum and also making equipment employed as minimum as possible is provided, which process comprises the steps of cooling and dedusting flue gas containing SO /SUB x/ ; contacting the cooled gas with a slurry containing limestone to remove SO /SUB x/ by absorption and also form CaSO/sub 3/; controlling the pH of the resulting slurry and then blowing air therein to form gypsum; and separating gypsum from the resulting slurry. As a modification of the above process, the slurry of the above second absorption step is further fed to the above first cooling step where unreacted limestone and SO /SUB x/ are reacted to form CaSO/sub 3/.

  3. Biocalcifying Bacillus subtilis cells effectively consolidate deteriorated Globigerina limestone.

    PubMed

    Micallef, Roderick; Vella, Daniel; Sinagra, Emmanuel; Zammit, Gabrielle

    2016-07-01

    Microbially induced calcite precipitation occurs naturally on ancient limestone surfaces in Maltese hypogea. We exploited this phenomenon and treated deteriorated limestone with biocalcifying bacteria. The limestone was subjected to various mechanical and physical tests to present a statistically robust data set to prove that treatment was indeed effective. Bacillus subtilis conferred uniform bioconsolidation to a depth of 30 mm. Drilling resistance values were similar to those obtained for freshly quarried limestone (9 N) and increased up to 15 N. Treatment resulted in a high resistance to salt deterioration and a slow rate of water absorption. The overall percentage porosity of treated limestone varied by ±6 %, thus the pore network was preserved. We report an eco-friendly treatment that closely resembles the mineral composition of limestone and that penetrates into the porous structure without affecting the limestones' natural properties. The treatment is of industrial relevance since it compares well with stone consolidants available commercially.

  4. LIFAC Sorbent Injection Desulfurization Demonstration Project. Quarterly report No. 9, October--December 1992

    SciTech Connect

    Not Available

    1992-12-31

    Sorbent injection is a potentially important alternative to conventional wet lime and limestone scrubbing, and this project is another effort to test alternative sorbent injection approaches. In comparison to wet systems, LIFAC, with recirculation of the sorbent, removes less sulfur dioxide - 75--85% relative to 90% or greater for conventional scrubbers -- and requires more reagent material. However, if the demonstration is wet scrubbing systems: LIFAC is relatively easy to retrofit to an existing boiler and requires less area than conventional wet FGD systems. LIFAC is less expensive to install than conventional wet FGD processes. LIFAC`s overall costs measured on a dollar-per-ton SO{sub 2} removed basis are less, an important advantage in a regulatory regime with trading of emission allocations. LIFAC produces a dry, readily disposable waste by-product versus a wet product. LIFAC is relatively simple to operate.

  5. LIFAC Sorbent Injection Desulfurization Demonstration Project. Quarterly report No. 10, January--March 1993

    SciTech Connect

    Not Available

    1993-09-01

    Sorbent injection is a potentially important alternative to conventional wet lime and limestone scrubbing, and this project is another effort to test alternative sorbent injection approaches. in comparison to wet systems, LIFAC, with recirculation of the sorbent, removes less sulfur dioxide -- 75--85% relative to 90% or greater for conventional scrubbers and requires more reagent material. However, if the demonstration is successful, LIFAC will offer these important advantages over wet scrubbing systems: Relatively easy to retrofit to an existing boiler and requires less area than conventional wet FGD systems; less expensive to install than conventional wet FGD processes; overall costs measured on a dollar-per-ton SO{sub 2} removed basis are less; produces a dry, readily disposable waste by-product versus a wet product; and is relatively simple to operate. The site for the LIFAC demonstration is Richmond Power and Light`s Whitewater Valley 2 pulverized coal-fired power station (60 MW), located in Richmond, Indiana.

  6. The Helderberg limestone of central Pennsylvania

    USGS Publications Warehouse

    Reeside, John B.

    1917-01-01

    This paper presents the results of a study made during 1913, 1914, and 1915, while the writer was a student at Johns Hopkins University. The formations discussed have been studies in Maryland, New Jersey, and New York, and described with more or less detail, but concerning their occurrence in the intervening area in Pennsylvania little exact information has been available. The conflict in opinion as to the proper position and correlation of the Keyser limestone and as to the interpretation of some of the standard New York sections has made further data very desirable, and the present paper is an attempt to meet a part of the deficiency.

  7. CO2 MITIGATION VIA ACCELERATED LIMESTONE WEATHERING

    SciTech Connect

    Rau, G H; Knauss, K G; Langer, W H; Caldeira, K G

    2004-02-27

    The climate and environmental impacts of our current, carbon-intensive energy usage demands that effective and practical energy alternatives and CO2 mitigation strategies be found. As part of this effort, various means of capturing and storing CO2 generated from fossil-fuel-based energy production are being investigated. One of the proposed methods involves a geochemistry-based capture and sequestration process that hydrates point-source, waste CO2 with water to produce a carbonic acid solution. This in turn is reacted and neutralized with limestone, thus converting the original CO2 gas to calcium bicarbonate in solution, the overall reaction being:

  8. Dynamic properties of Indiana, Fort Knox and Utah test range limestones and Danby Marble over the stress range 1 to 20 GPa

    SciTech Connect

    Furnish, M.D.

    1994-12-01

    The responses of the following carbonate materials to shock loading and release have been measured: Indiana limestone (18% porosity; saturated and dry), Jeffersonville/Louisville Limestones (Fort Knox limestone) (variable dolomitization, low porosity), Danby Marble (essentially pure calcite; low porosity), and a limestone from the Utah Test and Training Range (low porosity, with 22% silica). Various experimental configurations were used, some optimized to yield detailed waveform information, others to yield a clean combination of Hugoniot states and release paths. All made use of velocity interferometry as a primary diagnostic. The stress range of 0 - 20 GPa was probed (in most cases, emphasizing the stress range 0 -10 GPa). The primary physical processes observed in this stress regime were material strength, porosity, and polymorphic phase transitions between the CaCO{sub 3} phases I, II, III and VI. Hydration was also a significant reaction under certain conditions. The Indiana Limestone studies in particular represent a significant addition to the low-pressure database for porous limestone. Temperature dependence and the effect of freezing were assessed for the Fort Knox limestone. Experimental parameters and detailed results are provided for the 42 impact tests in this series.

  9. Elemental analysis of limestone samples from Ewekoro limestone deposit in southwest Nigeria

    NASA Astrophysics Data System (ADS)

    Obiajunwa, E. I.; Nwachukwu, J. I.

    2000-10-01

    Limestone samples of different colours from Ewekoro limestone deposit in Ogun State, Nigeria were subjected to elemental analysis by proton-induced X-ray emission (PIXE) and proton-induced gamma-ray emission (PIGME) techniques. The irradiation was by 2.5 MeV proton beams from the ion beam analysis (IBA) facility of the 3 MV Van de Graaff accelerator at the Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights. Elemental composition and concentrations of 22 major, minor and trace elements were determined. The NIST geological standard, NBS278, was analysed for quality assurance. The concentrations of the major elements (Ca, Fe, K and Al) are similar in the samples while the other major elements differed. Calcium accounts for about 38%, giving 86.8% CaCO 3 content in the limestones. The major elements (Al, Ca, Fe, Si, S and K), present in the limestones, were also found to be enriched in airborne particulate matter studied by earlier workers, thus confirming cement dust as the major contributor to the particulate matter within and around cement factories.

  10. Effects of salts on limestone dissolution rate in wet limestone flue gas desulfurization

    SciTech Connect

    Ukawa, Naohiko; Takashina, Toru; Oshima, Michio; Oishi, Tsuyoshi )

    1993-11-01

    To understand how the dissolution rate of limestone used for absorbent in a wet flue gas desulfurization plant is affected by the soluble salts formed from hydrogen chloride gas in flue gas as well as from the impurities contained in the used raw material limestone itself, various limestone slurries each supplemented with a single salt of CaCl[sub 2], MgCl[sub 2], NaCl, Na[sub 2]SO[sub 4] and MgSO[sub 4] were titrated with sulfuric acid. From the titration results the dissolution rate was found to vary greatly with the kind and the concentration of the salts with a general tendency to decrease in chloride solution but to increase in sulfate solutions. Based on this finding, the authors proposed a semi-empirical simplified model. The evaluated results using this model closely agreed with the measured values of the limestone dissolution rate both in single-salt solutions and mixed salt solutions. 9 refs., 8 figs., 1 tab.

  11. Adipic acid enhanced limestone flue gas desulfurization process - an assessment

    SciTech Connect

    Mobley, J.D.; Chang, J.C.S.

    1981-12-01

    Adipic acid, when used as an additive in a limestone FGD system, greatly increases both SO/sub 2/ removal and limestone utilization. Most existing limestone scrubbers would benefit from adipic acid addition without major process changes. No significant operating problems or adverse environmental impacts have been identified. The adipic acid enhanced system is economically attractive. Waste dibasic acids and glycolic acid appear to provide benefits similar to adipic acid at a lower cost.

  12. Limestone types used from the classic Karst region in Slovenia

    NASA Astrophysics Data System (ADS)

    Kramar, Sabina; Mirtič, Breda; Mladenović, Ana; Rožič, Boštjan; Bedjanič, Mojca; Kortnik, Jože; Šmuc, Andrej

    2014-05-01

    The paper presents a variety of limestones from the Karst Region that is one of the most interesting areas containing reserves of natural stones in Slovenia. The region is mainly composed of Cretaceous shallow-water limestone, with the most common type currently excavated being the rudist limestone of the Lipica Formation, which dates to the Santonian to Campanian. Limestones of this formation are mainly represented by a light grey, thick-bedded to massive Lipica limestone rich in (largely fragmented) rudists. Rudist shells can be either relatively well preserved (such as in Lipica Fiorito quarried limestone) or almost completely disintegrated and intensively endolitised (Lipica Unito quarried limestone). Beside the Lipica Formation, natural stone types have been excavated from two other formations or members in the Karst region: the Repen Formation (Repen and Kopriva limestones), and the Tomaj Limestone (dark, laminated limestone within the Lipica Formation). As documented, the region has been associated with the quarrying and processing of stone at least for over two thousand years, i.e. since the Roman period. Although a large number of quarries in all mentioned formations are documented in the Karst region, many are inactive nowadays. Some of the quarries are declared as geological monuments of national importance or officially protected as a natural monument. Karst limestones are considered the highest quality calcareous natural stones in Slovenia. They are characterised by high density, low water absorption and low open porosity; consequently they also exhibit high frost and salt resistance as well as high compressive and flexural strength. Besides in the Karst region and other parts of Slovenia, the Karst limestones were used in the construction of several important buildings and monuments in many other European Countries, and worldwide. Nowadays, they are most commonly used in the construction of façade cladding, pavements, window sills, staircases, indoor

  13. [Effects of variable temperature on organic carbon mineralization in typical limestone soils].

    PubMed

    Wang, Lian-Ge; Gao, Yan-Hong; Ding, Chang-Huan; Ci, En; Xie, De-Ti

    2014-11-01

    Soil sampling in the field and incubation experiment in the laboratory were conducted to investigate the responses of soil organic carbon (SOC) mineralization to variable temperature regimes in the topsoil of limestone soils from forest land and dry land. Two incubated limestone soils were sampled from the 0-10 cm layers of typical forest land and dry land respectively, which were distributed in Tianlong Mountain area of Puding county, Guizhou province. The soils were incubated for 56 d under two different temperature regimes including variable temperature (range: 15-25 degrees C, interval: 12 h) and constant temperature (20 degrees C), and the cumulative temperature was the same in the two temperature treatments. In the entire incubation period (56 d), the SOC cumulative mineralization (63.32 mg x kg(-1)) in the limestone soil from dry land (SH) under the variable temperature was lower than that (63.96 mg x kg(-1)) at constant 20 degrees C, and there was no significant difference in the SOC cumulative mineralization between the variable and constant temperature treatments (P < 0.05). While the cumulative mineralization (169.46 mg x kg(-1)) of organic carbon in the limestone soil from forest land (SL) under the variable temperature was significantly lower than that (209.52 mg x kg(-1)) at constant 20 degrees C. The results indicated that the responses of SOC mineralization to the variable temperature were obviously different between SL and SH soils. The SOC content and composition were significantly different between SL and SH soils affected by vegetation and land use type, which suggested that SOC content and composition were important factors causing the different responses of SOC mineralization to variable temperature between SL and SH soils. In addition, the dissolved organic carbon (DOC) content of two limestone soils were highly (P < 0.01) positively correlated with daily mineralization of soil organic carbon in both temperature treatments, which implied that

  14. The influence of spray-drying parameters on phase behavior, drug distribution, and in vitro release of injectable microspheres for sustained release.

    PubMed

    Meeus, Joke; Lenaerts, Maité; Scurr, David J; Amssoms, Katie; Davies, Martyn C; Roberts, Clive J; Van Den Mooter, Guy

    2015-04-01

    For ternary solid dispersions, it is indispensable to characterize their structure, phase behavior, and the spatial distribution of the dispersed drug as this might influence the release profile and/or stability of these formulations. This study shows how formulation (feed concentration) and process (feed rate, inlet air temperature, and atomizing air pressure) parameters can influence the characteristics of ternary spray-dried solid dispersions. The microspheres considered here consist of a poly(lactic-co-glycolic acid) (PLGA) surface layer and an underlying polyvinylpyrrolidone (PVP) phase. A poorly soluble active pharmaceutical ingredient (API) was molecularly dispersed in this matrix. Differences were observed in component miscibility, phase heterogeneity, particle size, morphology, as well as API surface coverage for selected spray-drying parameters. Observed differences are likely because of changes in the droplet generation, evaporation, and thus particle formation processes. However, varying particle characteristics did not influence the drug release of the formulations studied, indicating the robustness of this approach to produce particles of consistent drug release characteristics. This is likely because of the fact that the release is dominated by diffusion from the PVP layer through pores in the PLGA surface layer and that observed differences in the latter have no influence on the release.

  15. The Surface of a Limestone-Rich World?

    NASA Astrophysics Data System (ADS)

    Melis, Carl; Dufour, Patrick

    2016-06-01

    We present spectroscopic observations of the dust- and gas-enshrouded, polluted white dwarf star SDSSJ104341.53+085558.2 (hereafter SDSSJ1043). Hubble Space Telescope Cosmic Origins Spectrograph far-ultraviolet spectra combined with deep Keck HIRES optical spectroscopy reveal the elements C, O, Mg, Al, Si, P, S, Ca, Fe, and Ni and enable useful limits for Sc, Ti, V, Cr, and Mn in the photosphere of SDSSJ1043. From this suite of elements we determine that the parent body being accreted by SDSSJ1043 is dry, rocky, and iron-poor. Synthesizing all available heavily-polluted white dwarf measurements, we find a trend in the Fe/Mg vs Fe/Si abundance ratio-space suggestive of whether accreted material originates from the inner or outer regions of a rocky body; we use this trend to identify the material being accreted by SDSSJ1043 as likely to have come from the outermost layers of a differentiated object. Enhanced levels of Ca and C in this object can be explained by the presence of significant amounts of calcium-carbonate and, if definitive, could be suggestive of a world with a crust rich in limestone.

  16. Local facies variability in the Mission Canyon Limestone, west flank, Bighorn Mountains, Wyoming

    SciTech Connect

    Vice, M.A.; Utgaard, J.E. )

    1991-06-01

    Comparison of two sections of the Mission Canyon Limestone (Madison Group, Mississippian) located approximately one-half mile (850-900 m) apart and at opposite ends of a single flatiron reveals significant lateral facies variations. The southern section, Dry Fork of Horse Creek, is 83 ft (25 m) thicker than the northern Horse Creek section. This substantial difference in thickness cannot be attributed solely to pre-Amsden erosion and solution collapse: all three members are thicker and more variable lithologically at Dry Fork. The lower (Big Goose) member is composed mostly of cherty, dolomitized lime mudstones at both locations. At Dry Fork, it contains numerous skeletal facies, particularly in the upper part. Skeletal facies are insignificant at Horse Creek. The two upper members are composed mainly of skeletal limestones; however, grain-supported facies are much more abundant at Dry Fork. Dolomitized mudstones predominate in the major breccia at the base of the middle (Little Tongue) member at Horse Creek, and lime mudstones predominate at Dry Fork. Additional breccias occur at other horizons: five at Dry Fork, four at Horse Creek. Conclusions drawn from the initial study of these two outcrops follow: (1) the local extent of grainstones and packstones suggests that the shoals were geographically less extensive than the subtidal muddy bottoms and intertidal-supratidal mud flats. (2) The limited geographic and vertical extent of some breccias suggests evaporiate deposition in localized muddy facies. (3) Conditions favoring dolomitization were limited mainly to the mudstones and occurred during and shortly after deposition of the Big Goose Member.

  17. [Analysis of trace elements in limestone for archeological functions

    SciTech Connect

    Blanc, A.; Holmes, L.; Harbottle, G.

    1998-12-31

    Numerous quarries in the Lutetian limestone formations of the Paris Basin provided stone for the building and the decoration of monuments from antiquity to the present. To determine the origin of stone used for masonry and sculptures in these monuments, a team of geologists and archaeologists has investigated 300 quarries and collected 2,300 samples. Petrographic and paleontologic examination of thin sections allows geologists to distinguish Lutetian limestones from Jurassic and Cretaceous limestones. Geologists also seek to formulate hypotheses regarding the origin of Lutetian limestones used for building and sculpture in the Paris region. In the search for the sources of building and sculptural stone, the analytical methods of geologists are limited because often several quarries produce the same lithofacies. A new tool is now available, however, to attack questions of provenance raised by art historians. Because limestones from different sources have distinctive patterns of trace-element concentrations, compositional analysis by neutron activation allows one to compare building or sculptural stone from one monument with stone from quarries or other monuments. This analytical method subjects a powdered limestone sample to standard neutron activation analysis procedures at Brookhaven National Laboratory. With the help of computer programs, the compositional fingerprints of Lutetian limestones can be determined and stored in a database. The limestone database contains data for approximately 2,100 samples from monuments, sculptures and quarries. It is particularly rich in samples from the Paris Basin.

  18. [Reactivity of the limestone in wet flue gas desulfurization].

    PubMed

    Zhu, Tian-le; Li, Yao; Ling, Xuan; Liu, Hong-ju; Xu, Feng-gang; Liu, Han-qiang

    2005-11-01

    On the basis of the analysis of chemical components of the natural limestones from different deposits in China, the pore structures of the typical limestones, with the different CaCO3 content, were examined. The reactivity of the limestones was investigated by sulfuric acid titration and gas-liquid absorption methods. The research results showed that the specific surface area of the natural limestones studied in this work was about 1.8 m2/g. It was seen that the pH of the limestone slurry rapidly decreased and then back up when the sulfuric acid was added. The higher the CaCO3 content was, or the smaller the particle size was, the larger the pH back-up rate was, and similarly the faster the SO2 concentration of the reactor outlet increased. The Reactivity of the limestone obtained by the sulfuric acid titration had the same features as that obtained by the gas liquid absorption. Compared with the specific surface area, the CaCO3 content had more effect on the reactivity of the limestones. The particle size of the limestones had a significant effect on the reactivity when the particle size was relatively large, that is less than 300-360 mesh, vice versa.

  19. Microfacies and diagenesis of the reefal limestone, Callovian Tuwaiq Mountain Limestone Formation, central Saudi Arabia

    NASA Astrophysics Data System (ADS)

    EL-Sorogy, Abdelbaset S.; Almadani, Sattam A.; Al-Dabbagh, Mohammad E.

    2016-03-01

    In order to document the microfacies and diagenesis of the reefal limestone in the uppermost part of the Callovian Tuwaiq Mountain Limestone Formation at Khashm Al-Qaddiyah area, central Saudi Arabia, scleractinian corals and rock samples were collected and thin sections were prepared. Coral framestone, coral floatstone, pelloidal packstone, bioclastic packstone, bioclastic wacke/packstone, algal wackestone and bioclastic foraminiferal wacke/packstone were the recorded microfacies types. Cementation, recrystallization, silicification and dolomitization are the main diagenetic alterations affected the aragonitic skeletons of scleractinian corals. All coral skeletons were recrystallized, while some ones were dolomitized and silicified. Microfacies types, as well as the fossil content of sclearctinian corals, bivalves, gastropods, brachiopods and foraminifera indicated a deposition in environments ranging from shelf lagoon with open circulation in quiet water below wave base to shallow reef flank and organic build up for the uppermost reefal part of the Tuwaiq Formation in the study area.

  20. Faunas of Mississippian oolitic limestones: Evidence from Salem Limestone, southern Indiana

    SciTech Connect

    Feldman, H.R. )

    1989-08-01

    In the Salem Limestone of southern Indiana, a correlation exists between the faunal assemblage and abundance of grains with superficial oolitic coatings in grainstones. Coarse, poorly sorted fossiliferous grainstones are dominated by an echinoderm-bryozoan-brachiopod assemblage of fossils with few mollusks. The presence of large whole fossils, such as articulated crinoid calyces, suggest limited transport of skeletal components. Grainstones, dominated by grains with superficial coatings, and foraminifers tend to contain a diverse mollusk-dominated assemblage of gastropods, bivalves, rostroconchs, chitins, and scaphopods. These fossils are disarticulated, but generally are not fragmented even though many of them are thin and delicate. Echinoderms, brachiopods, and bryozoans are repsented in the mollusk-domdinated assemblage almost exclusively by well-rounded and coated fragments, suggesting that they are not in situ. The presence of similar molluscan assemblages in other Mississippian coated-grain grainstones from Alabama (the Monteagle Limestone) and Oklahoma (an unnamed limestone) indicates that the assemblage may have been wide-spread. Mississippian grainstones dominated by oolites (which are not prominent in the Salem) generally have very few fossils.

  1. Field trial of a pulsed limestone diversion well

    USGS Publications Warehouse

    Sibrell, Philip L.; Denholm, C.; Dunn, Margaret

    2013-01-01

    The use of limestone diversion wells to treat acid mine drainage (AMD) is well-known, but in many cases, acid neutralization is not as complete as would be desired. Reasons for this include channeling of the water through the limestone bed, and the slow reaction rate of the limestone gravel. A new approach to improve the performance of the diversion well was tested in the field at the Jennings Environmental Education Center, near Slippery Rock, PA. In this approach, a finer size distribution of limestone was used so as to allow fluidization of the limestone bed, thus eliminating channeling and increasing particle surface area for faster reaction rates. Also, water flow was regulated through the use of a dosing siphon, so that consistent fluidization of the limestone sand could be achieved. Testing began late in the summer of 2010, and continued through November of 2011. Initial system performance during the 2010 field season was good, with the production of net alkaline water, but hydraulic problems involving air release and limestone sand retention were observed. In the summer of 2011, a finer size of limestone sand was procured for use in the system. This material fluidized more readily, but acid neutralization tapered off after several days. Subsequent observations indicated that the hydraulics of the system was compromised by the formation of iron oxides in the pipe leading to the limestone bed, which affected water distribution and flow through the bed. Although results from the field trial were mixed, it is believed that without the formation of iron oxides and plugging of the pipe, better acid neutralization and treatment would have occurred. Further tests are being considered using a different hydraulic configuration for the limestone sand fluidized bed.

  2. Strain localization in direct shear experiments on Solnhofen limestone at high temperature Effects of transpression

    NASA Astrophysics Data System (ADS)

    Llana-Fúnez, Sergio; Rutter, Ernest H.

    2008-11-01

    Some features of natural shear zones formed under non-coaxial strain geometries, including some effects of transpression, can be simulated in the laboratory by using the direct shear experimental configuration. Slices of ˜1 mm thick Solnhofen limestone were deformed in direct shear between two stronger forcing blocks of cores of Tennessee sandstone pre-cut at 45° to the cylinder axis. Experiments were run dry at 600 °C, 200 MPa confining pressure and bulk shear strain rates of ˜5 × 10 -3 s -1, at which conditions Solnhofen limestone deformed by dislocation creep with a stress exponent of 4.7. When loaded, strain concentrates in the limestone band, producing non-coaxial deformation as one pre-cut block slides past the other. The orientation and intensity of the shape fabric developed in calcite grains indicate that strain is heterogeneous across the specimen, with the formation of two high-strain shear bands close to the limestone-sandstone interface, separated by a central zone of low strain. Crystallographic preferred orientation patterns in the calcite grains measured by electron backscatter diffraction are consistent with a switch in deformation geometry from flattening-dominated in the middle of the specimen towards shear-dominated in the high-strain bands. From tests on thin slices of the same material compressed axisymmetrically (without shearing) normal to the layer, heterogeneous thinning of the slice develops, from a maximum in the centre of the slice to zero at the edges. The formation of the paired shear zones observed in the sheared experiments is interpreted in terms of superposed strain fields, with shearing in the centre of the slice being inhibited by the strain hardening that accompanies the higher flattening strain in the centre of the specimen.

  3. Limestone dissolution in flue gas scrubbing: Effect of sulfite

    SciTech Connect

    Gage, C.L.; Rochelle, G.T. )

    1992-07-01

    Batch limestone dissolution experiments were carried out in a pH stat apparatus at 55 C with CO{sub 2} sparging and dissolved sulfite. Particle size distribution, utilization, sulfite in solution, limestone type, and the approach to calcite equilibrium were all found to contribute to the limestone reactivity. In the absence of sulfite, limestone dissolution was controlled solely by mass transfer. For a given stone under mass transfer control, film thickness was found to be independent of pH. The dissolution rate in the presence of sulfite was controlled by a combined surface kinetics/mass transfer regime. SEM micrographs supported this conclusion. A surface rate correlation was developed which accounted for observed inhibition by an inverse dependence on calcium sulfite concentration at the limestone dependence on calcium sulfite concentration at the limestone surface. While the form of the rate expression was applicable to all stones, the surface rate constant was stone dependent. A computer code which accounted for mass transfer with surface kinetics was tested against experimental observations of four limestone types. Changes in pH and the concentrations of calcium, carbonate, sulfite, sulfate, and adipic acid were accurately modeled.

  4. Geology of Vanport limestone (Pennsylvanian) in Elk County, Pennsylvania

    SciTech Connect

    Kuntz, T.J.

    1987-09-01

    The northernmost exposures of the Vanport limestone appear in Elk and southern McKean Counties, Pennsylvania. The Vanport limestone is structurally preserved in N45/sup 0/-50/sup 0/E trending synclinal folds. Surface exposures are almost all incomplete due to erosion. Drill-hole data assisted in defining areas of nondeposition within Elk County, variations in thickness, and erosional loss by channeling. The Vanport limestone thins to the southeast within Elk County and probably changes from limestone to a shaly limestone (transition zone) and then to shale. Analysis of 70 limestone samples indicated an average insoluble-residue content of 11.4%. The insoluble residue, mainly clay, increases toward the southeast, the direction of paleoshoreline and source of terrigenous sediments. A lack of quartz grains suggests a lack of detrital input from the source area. A study of the vertical variation of the total insoluble-residue content displayed an increase at the bottoms and tops of the stratigraphic section, mirroring the transgressive-regressive phases of the Vanport sea. The majority of allochems were skeletal material in a micritic matrix. Most abundant were mollusks, followed by forams, brachiopods, echinoderms, ostracods, and bryozoans. Composita brachiopods and pseudopunctate and/or punctate brachiopods inhabited offshore stillstand and nearshore transgressive-regressive environments, respectively. Other fossil assemblages displayed spatial and temporal variation. A darker matrix color occurred in stratigraphic sections closer to the paleoshoreline, due to higher clay and organic content. More offshore stratigraphic sections of the limestone were noticeably lighter in color.

  5. United Arab Emirates limestones: impact of petrography on thermal behavior

    NASA Astrophysics Data System (ADS)

    Alaabed, Sulaiman; Soltan, Abdel Monem; Abdelghany, Osman; Amin, Bahaa Eldin Mahmoud; El Tokhi, Mohamed; Khaleel, Abbas; Musalim, Abdullah

    2014-12-01

    The thermal behavior of selected limestones from representative localities of the United Arab Emirates is investigated for their suitability for soft-burnt lime production. The limestone samples were collected from the Ghalilah, Musandam, Shauiba, Muthaymimah, Dammam and Asmari formations. The samples were characterized for petrography, mineral and chemical composition, together with physico-mechanical characteristics. Investigative methods included transmitted light microscopy (TLM), cathodoluminescence (CLM) and scanning electron microscopy (SEM), as well as X-ray micro-tomography (μ-CT), XRD, XRF and Archimedes method. The limestone samples were fired in an electrical muffle furnace for 0.25, 0.5, 1 and 2 hours at 800, 900, 1,000 and 1,100 °C. After firing the lime grains were tested to determine their hydration rate and microfabric. The Ghalilah and Musandam limes show the lowest and highest maximum hydration rates, respectively, due mainly to the impure nature of the former, and the smaller lime crystallites and dominance of post-calcination micro-cracks of the latter. The Dammam and Asmari limes preserve a "ghost" microfabric of the original limestone. Higher allochem contents impose lower activation energy requirements for calcination, which implies earlier calcination of the allochems. The Musandam, Shauiba and Muthaymimah limestones may be useful for the production of reactive soft-burnt lime under the applied firing conditions, however, the Dammam and Asmari limestones need more advanced calcination conditions than the applied ones. The Ghalilah limestone was found to be unsuitable for the production of lime.

  6. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID CONTROL

    SciTech Connect

    Gary M. Blythe

    2000-12-01

    A test program is being sponsored by the US Department of Energy (DOE), EPRI, FirstEnergy, and TVA to investigate furnace injection of alkaline sorbents as a means of reducing sulfuric acid concentrations in the flue gas from coal-fired boilers. This test program is being conducted at the FirstEnergy Bruce Mansfield Plant (BMP), although later testing will be conducted at a TVA plant. A sorbent injection test was conducted the week of April 18, 2000. The test was the first of several short-term (one- to two-week duration) tests to investigate the effectiveness of various alkaline sorbents for sulfuric acid control and the effects of these sorbents on boiler equipment performance. This first short-term test investigated the effect of injecting dry dolomite powder (CaCO{sub 3} {center_dot} MgCO{sub 3}), a mineral similar to limestone, into the furnace of Unit 2. During the test program, various analytical techniques were used to assess the effects of sorbent injection. These primarily included sampling with the controlled condensation system (CCS) for determining flue gas SO{sub 3} content and an acid dew-point (ADP) meter for determining the sulfuric acid dew point (and, indirectly, the concentration of sulfuric acid) of the flue gas. EPA Reference Method 26a was used for determining hydrochloric acid (HCl) and hydrofluoric acid (HF), as well and chlorine (Cl{sub 2}) and fluorine (F{sub 2}) concentrations in the flue gas. Fly ash resistivity was measured using a Southern Research Institute (SRI) point-to-plane resistivity probe, and unburned carbon in fly ash was determined by loss on ignition (LOI). Coal samples were also collected and analyzed for a variety of parameters. Finally, visual observations were made of boiler furnace and convective pass surfaces prior to and during sorbent injection.

  7. EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY PIT ("THE OLD PIT") WITH LEDGE PREPARED FOR LIMESTONE EXTRACTION. AN ELEVEN-HOLE SHOT WILL DISLODGE APPROXIMATELY 25,000 TONS OF LIMESTONE WHICH, AFTER LOADING AND CRUSHING, WILL BE USED FOR ROAD CONSTRUCTION. THE CALERA QUARRY IS ONE OF FOUR ACTIVE VULCAN MATERIALS COMPANY QUARRIES IN THE DISTRICT. VULCAN MATERIALS, A FORTUNE 500 FIRM, ESTABLISHED IN BIRMINGHAM IN 1906 AS BIRMINGHAM SLAG COMPANY, VULCAN MATERIALS IS THE NATION'S FOREMOST PRODUCER OF CONSTRUCTION AGGREGATE AND A LEADING CHEMICALS MANUFACTURER - Vulcan Material Company, Calera Quarry, 1614 Highway 84, Calera, Shelby County, AL

  8. EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    EXTERIOR OVERVIEW, LOOKING NORTH, OF THIS 400' DEEP LIMESTONE QUARRY PIT ('THE OLD PIT') WITH LEDGE PREPARED FOR LIMESTONE EXTRACTION. AN ELEVEN-HOLE SHOT WILL DISLODGE APPROXIMATELY 25,000 TONS OF LIMESTONE WHICH, AFTER LOADING AND CRUSHING, WILL BE USED FOR ROAD CONSTRUCTION. THE CALERA QUARRY IS ONE OF FOUR ACTIVE VULCAN MATERIALS COMPANY QUARRIES IN THE DISTRICT. VULCAN MATERIALS, A FORTUNE 500 FIRM, ESTABLISHED IN BIRMINGHAM IN 1906 AS BIRMINGHAM SLAG COMPANY, VULCAN MATERIALS IS THE NATION'S FOREMOST PRODUCER OF CONSTRUCTION AGGREGATE AND A LEADING CHEMICALS MANUFACTURER. - Vulcan Material Company, Calera Quarry, 1614 Highway 84, Calera, Shelby County, AL

  9. Limestone - A Crucial and Versatile Industrial Mineral Commodity

    USGS Publications Warehouse

    Bliss, James D.; Hayes, Timothy S.; Orris, Greta J.

    2008-01-01

    Limestone, as used by the minerals industry, is any rock composed mostly of calcium carbonate (CaCO3). Although limestone is common in many parts of the United States, it is critically absent from some. Limestone is used to produce Portland cement, as aggregate in concrete and asphalt, and in an enormous array of other products, making it a truly versatile commodity. Portland cement is essential to the building industry, but despite our Nation's abundance of limestone, there have been cement shortages in recent years. These have been caused in part by a need to find new areas suitable for quarrying operations. To help manage our Nation's resources of such essential mineral commodities, the U.S. Geological Survey (USGS) provides crucial data and scientific information to industry, policymakers, and the public.

  10. LUTETIAN LIMESTONES IN THE PARIS REGION: PETROGRAPHIC AND COMPOSITIONAL EXAMINATION

    SciTech Connect

    BLANC,A.; HOLMES,L.L.; HARBOTTLE,G.

    1998-06-11

    Stone for building and decorating monuments in the Paris Basin from antiquity to the present came from numerous quarries in the Lutetian limestone formations of the region. To identify specific-stone sources used for masonry and sculptures in these monuments, a team of geologists and archaeologists has investigated 300 quarries and collected 2,300 limestone samples for study in a collaborative effort by geologists and chemists. Petrographic and paleontologic examinations of thin sections enable geologists to distinguish the Tertiary Lutetian limestones from similar stone in Jurassic and Cretaceous strata. The methods of the geologist have been supplemented by those of the chemist whose compositional studies by neutron activation analysis can differentiate among the fine-grained upper Lutetian limestones extracted from specific ancient quarries.

  11. Lutetian limestones in the Paris region: Petrographic and compositional examination

    SciTech Connect

    Blanc, A.; Holmes, L.L.; Harbottle, G.

    1998-12-31

    Stone for building and decorating monuments in the Paris Basin from antiquity to the present came from numerous quarries in the Lutetian limestone formations of the region. To identify specific stone sources used for masonry and sculptures in these monuments, a team of geologists and archaeologists have investigated 300 quarries and collected 2,300 limestone samples for study in a collaborative effort by geologists and chemists. Petrographic and paleontologic examinations of thin sections enable geologists to distinguish the Tertiary Lutetian limestones from similar stone in Jurassic and Cretaceous strata. The methods of the geologist have been supplemented by those of the chemistry whose compositional studies by neutron activation analysis can differentiate among the fine-grained upper Lutetian limestones extracted from specific ancient quarries.

  12. Limestone and bronze "Mississippi River Crossing" Bridge plaque located at ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Limestone and bronze "Mississippi River Crossing" Bridge plaque located at North corner of Administration Building site - Huey P. Long Bridge, Administration Building, 5100 Jefferson Highway, Jefferson, Jefferson Parish, LA

  13. 1. SOUTH FACADE. CONSTRUCTED (ca. 1895) OF INDIGENOUS LIMESTONE AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. SOUTH FACADE. CONSTRUCTED (ca. 1895) OF INDIGENOUS LIMESTONE AND USED AS LOCKPORTS CENTRAL HIGH SCHOOL FOR MORE THAN SIXTY YEARS. - Lockport Historic District, Central High School, Lockport, Will County, IL

  14. Facies patterns and depositional environments of Palaeozoic cephalopod limestones

    NASA Astrophysics Data System (ADS)

    Wendt, J.; Aigner, T.

    1985-07-01

    In the eastern Anti-Atlas (Morocco) a platform and basin topography was established during the late Devonian, probably as a result of early Variscan tensional tectonics. Cephalopod limestones were deposited on shallow pelagic platforms, platform slopes and shallow, slowly subsiding basins. On the platform a transition from land areas into nearshore quartzose brachiopod coquinas, crinoidal limestones, condensed cephalopod limestones and finally into nodular limestones is observed. The latter often become disintegrated into incipient debris flows which pass into nodular limestone/marl alternations of a shallow basin. Deeper basins with shale sedimentation lack cephalopod limestones. Similar facies types also occur in the late Devonian of the Montagne Noire (France), Rheinisches Schiefergebirge (West Germany), Moravian Karst (Czechoslovakia), Holy Cross Mountains (Poland) and in the early Carboniferous of the Cantabrian Mountains (Spain). Due to strong late Variscan compressional tectonics and limited outcrops, detailed facies patterns could not be mapped in these regions, but the same facies types as in the eastern Anti-Atlas suggest similar coast/platform, slope and shallow basin topographies. During cephalopod limestone deposition water depth on the platforms was in the order of several tens to about one hundred metres, as is inferred from repeated subaerial exposures and distinctive depositional and faunal/floral features. Water depth in the adjacent shallow basins might have reached several hundreds of metres. Cephalopod limestones represent a typical stage in the evolution of geosynclines, characterized by extremely low sedimentation rates (1-5 m m.y. -1). This stage is preceded by deposition of thick neritic clastics and/or carbonates and is succeeded by deposition of deep-water clastics or flysch.

  15. Dry Mouth

    MedlinePlus

    ... or chewing tobacco can increase dry mouth symptoms. Methamphetamine use. Methamphetamine use can cause severe dry mouth and damage to teeth, a condition also known as "meth mouth." If you don't have enough saliva ...

  16. Dry Mouth

    MedlinePlus

    Dry mouth is the feeling that there is not enough saliva in your mouth. Everyone has a dry mouth once in a while - if they are nervous, ... under stress. But if you have a dry mouth all or most of the time, it can ...

  17. Economic evaluation and comparison of alternative limestone-scrubbing options

    SciTech Connect

    Burnett, T.A.; Torstrick, R.L.; Sudhoff, F.A.

    1982-01-01

    The preliminary-grade economics (accuracy: -15%, +30%) of various alternative limestone scrubbing options (absorber type, with and without forced oxidation, and with and without adipic acid enhancement) are examined using the current design and economic premises established for the continuing series of economic evaluations performed by TVA for EPA. The economics are projected using the Shawnee lime/limestone computer model, which is based on long-term operating data from the EPA Alkali Scrubbing Test Facility at the TVA Shawnee Steam Plant near Paducah, Kentucky. The capital investment for the base-case limestone scrubbing process (500 MW, 3.5% sulfur coal, 1979 NSPS, spray tower, forced oxidation, landfill) is $206/kW. The first-year and levelized annual revenue requirements are 10.59 and 15.09 mills/kWh respectively. Costs for the equivalent limestone scrubbing process using a Turbulent Contact Absorber (TCA) are lower while those for the venturi - spray tower absorber are higher. The forced-oxidation landfill disposal option has a lower capital investment than the unoxidized pond disposal option for all cases studied; however, the first-year and levelized annual revenue requirements are slightly higher for the forced-oxidation landfill process for most coal applications. For the spray tower limestone process to achieve a specified SO/sub 2/ removal efficiency, it is more economical to increase the limestone stoichiometry and minimize the absorber L/G. The use of adipic acid or possibly dibasic acid (DBA) as an additive to enhance SO/sub 2/ removal in the limestone scrubbing process is an economically attractive option. The use of adipic acid remains economically attractive even if both a high unit cost and a high degradation factor for adpic acid are assumbed.

  18. Cabazitaxel Injection

    MedlinePlus

    ... injection is used along with prednisone to treat prostate cancer (cancer of a male reproductive organ) that has ... cabazitaxel injection is usually used in men with prostate cancer. If used by pregnant women, cabazitaxel injection can ...

  19. Fondaparinux Injection

    MedlinePlus

    ... fondaparinux injection.Talk to your doctor about the risk of using fondaparinux injection. ... Fondaparinux injection is used to prevent deep vein thrombosis (DVT; a blood ... Xa inhibitors. It works by decreasing the clotting ability of the blood.

  20. Morphine Injection

    MedlinePlus

    Morphine injection is used to relieve moderate to severe pain. Morphine is in a class of medications called opiate ( ... Morphine injection comes as a solution (liquid) to inject intramuscularly (into a muscle) or intravenously (into a ...

  1. Dexamethasone Injection

    MedlinePlus

    Dexamethasone injection is used to treat severe allergic reactions. It is used in the management of certain types of ... gastrointestinal disease, and certain types of arthritis. Dexamethasone injection is also used for diagnostic testing. Dexamethasone injection ...

  2. Romidepsin Injection

    MedlinePlus

    Romidepsin injection is used to treat cutaneous T-cell lymphoma (CTCL; a group of cancers of the immune system ... one other medication given by mouth or by injection. Romidepsin injection is in a class of medications ...

  3. Ondansetron Injection

    MedlinePlus

    Zofran® Injection ... Ondansetron injection is used to prevent nausea and vomiting caused by cancer chemotherapy and surgery. Ondansetron is in a ... medications: or any of the ingredients in ondansetron injection. Ask your pharmacist for a list of the ...

  4. Pilot-scale Limestone Emission Control (LEC) process: A development project. Volume 1, Main report and appendices A, B, C, and D: Final report

    SciTech Connect

    Prudich, M.E.; Appell, K.W.; McKenna, J.D.

    1994-03-01

    ETS, Inc., a pollution consulting firm with headquarters in Roanoke, Virginia, has developed a dry, limestone-based flue gas desulfurization (FGD) system. This SO{sub 2} removal system, called Limestone Emission Control (LEC), can be designed for installation on either new or existing coal-fired boilers. In the LEC process, the SO{sub 2} in the flue gas reacts with wetted granular limestone that is contained in a moving bed. A surface layer of principally calcium sulfate (CaSO{sub 4}) is formed on the limestone. Periodic removal of this surface layer by mechanical agitation allows high utilization of the limestone granules. A nominal 5,000 acfm LEC pilot plant has been designed, fabricated and installed on the slipstream of a 70,000 pph stoker boiler providing steam to Ohio University`s Athens, Ohio campus. A total of over 90 experimental trials have been performed using the pilot-scale moving-bed LEC dry scrubber as a part of this research project with run times ranging up to a high of 125 hours. SO{sub 2} removal efficiencies as high as 99.9% were achievable for all experimental conditions studied during which sufficient humidification was added to the LEC bed. The LEC process and conventional limestone scrubbing have been compared on an equatable basis using flue gas conditions that would be expected at the outlet of the electrostatic precipitator (ESP) of a 500 MW coal-fired power plant. The LEC was found to have a definite economic advantage in both direct capital costs and operating costs. Based on the success and findings of the present project, the next step in LEC process development will be a full-scale commercial demonstration unit.

  5. Modifying the properties of finely ground limestone by tumbling granulation

    NASA Astrophysics Data System (ADS)

    Macho, Oliver; Eckert, Maroš; Tomášová, Barbora; Peciar, Peter; Ščasný, Martin; Fekete, Roman; Peciar, Marián

    2016-06-01

    Calcium carbonate in the form of finely ground limestone is a material that has found its application in a wide range of industries, in the chemical, rubber, agricultural, and paper industries, is used for desulfurization of boilers and other. In civil engineering, ground limestone is used for the production of building materials, plaster and mortar mixtures, as a filler in concrete mixtures, in road construction, and as an essential component of mastic asphalt. This paper deals with examining the modification of the properties of finely ground limestone by the tumbling agglomeration method. It has been shown that the components of concrete with a round grain have a positive effect on the pumping of concrete in comparison with an elongated grain or the rough surface of crushed stone. The experiments will be carried out on a granulation plate using a variety of granulation liquid. The agglomerates and their properties were compared with untreated finely ground limestone, with a focus on detecting changes in compressibility, density and particle size. The output of this paper is a description and graphical representation of the changes in the properties of ground limestone before and after the agglomeration process.

  6. Pathogen and chemical transport in the karst limestone of the Biscayne aquifer: 2. Chemical retention from diffusion and slow advection

    USGS Publications Warehouse

    Shapiro, A.M.; Renken, R.A.; Harvey, R.W.; Zygnerski, M.R.; Metge, D.W.

    2008-01-01

    A tracer experiment, using a nonreactive tracer, was conducted as part of an investigation of the potential for chemical and pathogen migration to public supply wells that draw groundwater from the highly transmissive karst limestone of the Biscayne aquifer in southeastern Florida. The tracer was injected into the formation over approximately 1 h, and its recovery was monitored at a pumping well approximately 100 m from the injection well. The first detection of the tracer occurred after approximately 5 h, and the peak concentration occurred at about 8 h after the injection. The tracer was still detected in the production well more than 6 days after injection, and only 42% of the tracer mass was recovered. It is hypothesized that a combination of chemical diffusion and slow advection resulted in significant retention of the tracer in the formation, despite the high transmissivity of the karst limestone. The tail of the breakthrough curve exhibited a straight-line behavior with a slope of -2 on a log-log plot of concentration versus time. The -2 slope is hypothesized to be a function of slow advection, where the velocities of flow paths are hypothesized to range over several orders of magnitude. The flow paths having the slowest velocities result in a response similar to chemical diffusion. Chemical diffusion, due to chemical gradients, is still ongoing during the declining limb of the breakthrough curve, but this process is dwarfed by the magnitude of the mass flux by slow advection.

  7. Ibandronate Injection

    MedlinePlus

    Boniva® Injection ... Ibandronate injection is used to treat osteoporosis (a condition in which the bones become thin and weak and break ... Ibandronate injection comes as a solution (liquid) to be injected into a vein by a doctor or nurse in ...

  8. Leuprolide Injection

    MedlinePlus

    Leuprolide injection comes as a long-acting suspension (Lupron) that is injected intramuscularly (into a muscle) by a doctor or nurse in a medical ... Depot-4 month, Lupron Depot-6 Month). Leuprolide injection also comes as a long-acting suspension (Eligard) that is injected subcutaneously (just under ...

  9. Thermo-Hydro-Mechanical-Chemical Coupled Modeling of Geothermal Doublet Systems in Limestones -revised

    NASA Astrophysics Data System (ADS)

    Rühaak, Wolfram; Heldmann, Claus-Dieter; Pei, Liang; Bartels, Jörn; Weinert, Sebastian; Sass, Ingo

    2016-04-01

    Limestone aquifers in Southern Germany have been used within the last decade very successfully for geothermal heating and - to a lesser extent - for power generation. As an example the region around Munich has been extensively explored. While the extent of usage of this reservoir is increasing there is also an increased interest in better understanding of the reservoir properties and its change in the course of operation. For instance, the observed production and injection pressures are partly hard to explain. They may be related to mechanical or chemical processes, or both. Based on extensive data of outcrop studies and drillings, a data-base for the relevant physical properties of the respective limestones has been complied. The data include thermal conductivity, density, specific heat capacity, permeability, as well as mechanical properties like thermal expansion coefficient and elasticity modules. By using the hydro-thermo-chemical simulator FEFLOW together with an extension for thermo- and hydro-mechanical coupling the relevant processes are studied and compared with observed data. At the EGU Meeting in 2015 results of an initial study have been presented. This time results based on a completely new model setup and also using newly developed code will be presented. As a conclusion main challenges while modeling THMC fracture flow by using a multi-continua approach will be discussed.

  10. The Ançã limestones, Coimbra, Portugal

    NASA Astrophysics Data System (ADS)

    Quinta-Ferreira, Mário; Gil Catarino, Lídia; Delgado Rodrigues, José

    2016-04-01

    Ançã is located in the Lusitanian Basin (western Meso-Cenozoic sedimentary basin), in the municipality of Cantanhede, close to Coimbra, Portugal. This constitutes the northernmost Dogger (Bajocian) limestone sequence in Portugal. The use of the Ançã limestones is documented since the Roman occupation of the Iberian Peninsula. It was used for the construction of houses, palaces, churches, fine sculptures, carving, paving and for the production of lime. These limestones vary from white and very soft varieties, with very high porosity used for sculpture and carving to white and hard varieties used for masonry and as aggregates and to white to bluish with low porosity and high strength varieties, mainly used for paving. The softer and whiter variety is worldwide known as Ançã Stone (Pedra de Ançã) exhibiting a porosity of 26-29 %. It became famous after being largely used by Coimbra most famous Renaissance sculptors like João de Ruão and Nicolau de Chanterenne. The Pedra de Ançã was used mainly in the region of Coimbra, but also in several other places in Portugal, in Santiago de Compostela, Spain, and Brazil. Some examples of heritage in Coimbra using the Pedra de Ançã are the renaissance portal of the Saint Cross Church, the tombs of the first two Portuguese kings located in this church, the altar of the Saint Cross Church or of the Old Cathedral, or in sculptures at the University of Coimbra. It is quite prone to deteriorate when exposed to atmospheric agents and to soluble salts, mainly due to its high porosity. Deteriorated surfaces needing treatment constitute difficult conservation problems, especially when consolidation and protection treatments are required. The less porous varieties of the Ançã limestones (< 20 % porosity) were mainly used for masonry, paving and production of lime. The royal Palace of Buçaco is a remarkable masonry building constructed at the end of the XIX century with the less porous varieties of the Ançã limestones

  11. Leaching of clay minerals in a limestone environment

    USGS Publications Warehouse

    Carroll, D.; Starkey, H.C.

    1959-01-01

    Water saturated with CO2 at about 25??C was percolated through mixed beds of limestone or marble fragments and montmorillonite, "illite" and kaolinite in polyethylene tubes for six and fortyfive complete runs. The leachates were analysed for SiO2, A12O3 and Fe2O3, but only SiO2 was found. The minerals lost SiO2 in this order: montmorillonite > kaolinite > "illite". The differential removal of SiO2 during the short period of these experiments suggests a mechanism for the accumulation of bauxite deposits associated with limestones. ?? 1959.

  12. Novel Hydroxyapatite Coatings for the Conservation of Marble and Limestone

    NASA Astrophysics Data System (ADS)

    Naidu, Sonia

    Marble and limestone are calcite-based materials used in the construction of various structures, many of which have significant artistic and architectural value. Unfortunately, due to calcite's high dissolution rate, these stones are susceptible to chemically-induced weathering in nature. Limestone, due to its inherent porosity, also faces other environmental weathering processes that cause weakening from disintegration at grain boundaries. The treatments presently available are all deficient in one way or another. The aim of this work is to examine the feasibility of using hydroxyapatite (HAP) as a novel protective coating for marble and limestone, with two goals: i) to reduce acid corrosion of marble and ii) to consolidate physically weathered limestone. The motivation for using HAP is its low dissolution rate and structural compatibility with calcite. Mild, wet chemical synthesis routes, in which inorganic phosphate-based solutions were reacted with marble and limestone, alone and with other precursors, were used to produce HAP films. Film nucleation, growth and phase evolution were studied on marble to understand film formation and determine the optimal synthesis route. An acid resistance test was developed to investigate the attack mechanism on marble and quantify the efficacy of HAP-based coatings. Film nucleation and growth were dependent on substrate surface roughness and increased with calcium and carbonate salt additions during synthesis. Acid attack on marble occurred via simultaneous dissolution at grain boundaries, twin boundaries and grain surfaces. HAP provided intermediate protection against acid attack, when compared to two conventional treatments. Its ability to protect the stone from acid was not as significant as predicted from dissolution kinetics and this was attributed to incomplete coverage and residual porosity within the film, arising from its flake-like crystal growth habit, which enabled acid to access the underlying substrate. The

  13. Habitat use and locomotion of the François' langur (Trachypithecus francoisi) in limestone habitats of Nonggang, China.

    PubMed

    Zhou, Qihai; Luo, Bang; Wei, Fuwen; Huang, Chengming

    2013-12-01

    We collected data on habitat use and locomotion of the François' langur (Trachypithecus francoisi) between August 2003 and July 2004 at Nonggang Nature Reserve, China. A total of 739 h of behavioral data were collected during this study. We tested 2 predictions: (1) that the langurs may have special patterns of habitat use and locomotion adaptive to the limestone habitat, and (2) the langurs may exhibit different patterns of habitat use and locomotion among different zones of limestone hill. Our results indicated that François- langurs spent more time in the low-risk, relatively food-poor cliff-hilltop areas. When young leaves and fruit were scarce in the dry season, the langurs increased their time in the high-risk, food-rich valley basin. François- langurs were semi-terrestrial, and leaping and climbing were their main locomotor modes. These behavioral patterns are considered to be related to characteristics of topography and vegetation in limestone habitat, such as large areas of cliff and discontinuous canopy. Our results also supported Prediction 2. The langurs confined locomotion to the main canopy and frequently adopted leaping while traveling in the hillside and valley basin. While traveling in cliff-hilltop areas, they tended to stay in the lower stratus (≤5 m) or move on the ground, and walking and climbing were their dominant traveling modes.

  14. View of the main entrance with basrelief limestone panel designed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of the main entrance with bas-relief limestone panel designed by C. Paul Jennwein upon which is inscribed "Lege Atque Ordine Omnia Fiunt" (translated as by law and order all is accomplished) - United States Department of Justice, Constitution Avenue between Ninth & Tenth Streets, Northwest, Washington, District of Columbia, DC

  15. Detail view to show one of the limestone relief panels ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view to show one of the limestone relief panels depicting one of the agencies of the Commerce Department, here the Lighthouse Service - United States Department of Commerce, Bounded by Fourteenth, Fifteenth, and E streets and Constitution Avenue, Washington, District of Columbia, DC

  16. The Solnhofen Limestone: A stony heritage of many uses

    NASA Astrophysics Data System (ADS)

    Kölbl-Ebert, Martina; Kramar, Sabina; Cooper, Barry J.

    2016-04-01

    High above the valley of the River Altmühl (Bavaria, Germany), between Solnhofen to the west and Kelheim to the east, numerous quarries give access to thinly plated limestone from the Upper Jurassic, some 150 million years before the present. The main quarry areas lie around the town of Eichstätt and between the villages of Solnhofen, Langenaltheim and Mörnsheim. Here limestone slabs have been quarried for several hundred years, some even in Roman times. Solnhofen Limestone is famous worldwide; not only because it is a beautiful building stone of high quality, but also because of the exceptionally well-preserved fossils it contains -among them the early bird Archaeopteryx. The quarry industry between Solnhofen and Eichstätt has shaped a cultural landscape, with old and new quarries sunk into the plain and numerous spoil heaps rising above it, for the rock is not all economically useful. But many of the spoil heaps and the old quarries are environmentally protected as they provide a habitat for some rare plants and animals. It is not necessary to cut the Solnhofen Limestone with a saw: it is split by hand into thin and even slabs or sheets which are used for flagstones and wall covers, which since centuries are sold world-wide. Locally it also serves as roof tiles for traditional houses. Thick slabs of especially fine quality may be found near Solnhofen and Mörnsheim and are used for lithography printing.

  17. Limestone weathering rates accelerated by micron-scale grain detachment

    NASA Astrophysics Data System (ADS)

    Emmanuel, S.; Levenson, Y.

    2014-12-01

    The weathering rates of carbonate rocks is often thought to be controlled by chemical dissolution, although some studies have suggested that mechanical erosion could also play an important role. Quantifying the rates of the different processes has proved challenging due to the high degree of variability encountered in both field and lab settings. To determine the rates and mechanisms controlling long-term limestone weathering, we analyse a lidar scan of the Western Wall, a Roman period edifice located in Jerusalem. Weathering rates in fine-grained micritic limestone blocks are up to 2 orders of magnitude higher than the average rates estimated for coarse-grained limestone blocks at the same site. In addition, in experiments that use atomic force microscopy to image dissolving micritic limestone, we show that these higher reaction rates could be due to rapid dissolution along micron-scale grain boundaries, followed by mechanical detachment of tiny particles from the surface. Our analysis indicates that micron-scale grain detachment, rather than pure chemical dissolution, could be the dominant erosional mode for fine-grained rocks in many carbonate terrains.

  18. Curved limestone wall at east end of rail yard. Note ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Curved limestone wall at east end of rail yard. Note cut off valves at base of stump in right foreground, and utility tunnel in middle distance, superindent's house at right, looking NW. - Grand Canyon Village Utilities, Grand Canyon National Park, Grand Canyon Village, Coconino County, AZ

  19. The influence of additives on rheological properties of limestone slurry

    NASA Astrophysics Data System (ADS)

    Jaworska, B.; Bartosik, A.

    2014-08-01

    Limestone slurry appears in the lime production process as the result of rinsing the processed material. It consists of particles with diameter smaller than 2 mm and the water that is a carrier of solid fraction. Slurry is directed to the settling tank, where the solid phase sediments and the excess water through the transfer system is recovered for re-circulation. Collected at the bottom of the tank sludge is deposited in a landfill located on the premises. Rheological properties of limestone slurry hinder its further free transport in the pipeline due to generated flow resistance. To improve this state of affairs, chemical treatment of drilling fluid, could be applied, of which the main task is to give the slurry properties suitable for the conditions encountered in hydrotransport. This treatment consists of applying chemical additives to slurry in sufficient quantity. Such additives are called as deflocculants or thinners or dispersants, and are chemical compounds which added to aqueous solution are intended to push away suspended particles from each other. The paper presents the results of research allowing reduction of shear stress in limestone slurry. Results demonstrate rheological properties of limestone slurry with and without the addition of modified substances which causes decrease of slurry viscosity, and as a consequence slurry shear stress for adopted shear rate. Achieving the desired effects increases the degree of dispersion of the solid phase suspended in the carrier liquid and improving its ability to smooth flow with decreased friction.

  20. Soil respiration patterns and controls in limestone cedar glades

    USGS Publications Warehouse

    Cartwright, Jennifer M.; Hui, Dafeng

    2015-01-01

    Soil depth, SOM, and vegetation cover were important drivers of Rs in limestone cedar glades. Seasonal Rs patterns reflected those for mesic temperate grasslands more than for semi-arid ecosystems, in that Rs primarily tracked temperature for most of the year.

  1. Geology of the Limestone Hills, Broadwater County, Montana

    USGS Publications Warehouse

    Ruppel, Edward Thompson

    1950-01-01

    The Limestone Hills, a natural topographic unit having an area of about 16 square miles, are situated a few miles west and southwest of Townsend, Broadwater County, Montana. They are composed of pre-Cambrian, Paleozoic, and Mesozoic sedimentary rocks i

  2. 14. A VIEW SOUTHEAST OF A PORTION OF THE LIMESTONE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. A VIEW SOUTHEAST OF A PORTION OF THE LIMESTONE ABUTMENT, THE UNDERSIDE OF THE INCLINED END POST AND A PLATE USED TO ATTACH THE STRUCTURE TO THE ABUTMENT. - Wells County Bridge No. 74, Spanning Rock Creek Ditch at County Road 400, Bluffton, Wells County, IN

  3. 44. Tube conveyors carry ore, coke and limestone to blast ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    44. Tube conveyors carry ore, coke and limestone to blast furnaces "B" and "C". Ore bridges to left, passenger elevator penthouse immediately to left of conveyor; gas stack and furnace "A" to right. Looking north - Rouge Steel Company, 3001 Miller Road, Dearborn, MI

  4. STRUCTURAL CHANGES IN SURFACTANT-MODIFIED SORBENTS DURING FURNACE INJECTION

    EPA Science Inventory

    A calcium hydroxide [Ca(OH)2] sorbent modified by the addition of calcium lignosulfonate has recently been developed for use in the Environmental Protection Agency's limestone injection multistage burner process. The increased reactivity with sulfur dioxide (SO2) displayed by thi...

  5. Laboratory Investigations in Support of Carbon Dioxide-Limestone Sequestration in the Ocean

    SciTech Connect

    Dan Golomb; Eugene Barry; David Ryan; Carl Lawton; Stephen Pennell; Peter Swett; Huishan Duan; Michael Woods

    2005-11-01

    This semi-annual progress reports includes further findings on CO{sub 2}-in-Water (C/W) emulsions stabilized by fine particles. In previous semi-annual reports we described the formation of stable C/W emulsions using pulverized limestone (CaCO{sub 3}), flyash, beach sand, shale and lizardite, a rock rich in magnesium silicate. For the creation of these emulsions we used a High-Pressure Batch Reactor (HPBR) equipped with view windows for illumination and video camera recording. For deep ocean sequestration, a C/W emulsion using pulverized limestone may be the most suitable. (a) Limestone (mainly CaCO{sub 3}) is cheap and plentiful; (b) limestone is innocuous for marine organisms (in fact, it is the natural ingredient of shells and corals); (c) it buffers the carbonic acid that forms when CO{sub 2} dissolves in water. For large-scale sequestration of a CO{sub 2}/H{sub 2}O/CaCO{sub 3} emulsion a device is needed that mixes the ingredients, liquid carbon dioxide, seawater, and a slurry of pulverized limestone in seawater continuously, rather than incrementally as in a batch reactor. A practical mixing device is a Kenics-type static mixer. The static mixer has no moving parts, and the shear force for mixing is provided by the hydrostatic pressure of liquid CO{sub 2} and CaCO{sub 3} slurry in the delivery pipes from the shore to the disposal depth. This semi-annual progress report is dedicated to the description of the static mixer and the results that have been obtained using a bench-scale static mixer for the continuous formation of a CO{sub 2}/H{sub 2}O/CaCO{sub 3} emulsion. The static mixer has an ID of 0.63 cm, length 23.5 cm, number of baffles 27. Under pressure, a slurry of CaCO{sub 3} in artificial seawater (3.5% by weight NaCl) and liquid CO{sub 2} are co-injected into the mixer. From the mixer, the resulting emulsion flows into a Jerguson cell with two oblong windows on opposite sides, then it is vented. A fully ported ball valve inserted after the Jerguson

  6. Isotopic labeling for the understanding of the alteration of limestone used in built cultural heritage

    NASA Astrophysics Data System (ADS)

    Saheb, Mandana; Chabas, Anne; Mertz, Jean-Didier; Rozenbaum, Olivier; Verney-Carron, Aurélie

    2015-04-01

    This project belongs to a specific work aiming at developing isotopic tools to better understand the alteration of materials used in the built cultural heritage. It is focused on the study of the alteration of limestone used in the facades of historic buildings subject to atmospheric polluted environment. Actually in the elevated parts of the buildings, water as rainfall (runoff or wet deposition) or in vapor form (condensation or dry deposition) is the main agent of alteration. Thus, the rock/water interactions need to be well understood to propose adapted solution to better preserve the buildings. To identify the water transfer within the porous limestone and locate the reaction preferential sites, two isotopic tracers (D and 18O) are used to monitor the alteration solution (D) and locate the zones containing the secondary phases (18O). The Saint-Maximin limestone used in many monuments in the suburbs of Paris (France) as a building and restoration stone has been specifically studied. Pristine materials, stones from monuments (monuments in the Paris area) and samples altered in laboratory constitute the analytical corpus to compare different stages of alteration. In a first step the stones are characterized at different scales to identify the alteration pattern (SEM-EDS, Raman microspectrometry, XRD, rugosimetry) and study the water transfers (X-ray tomography, mercury porosimetry, imbibition kinetics). The samples are then altered in the laboratory by realistic and controlled wet or dry deposition using isotopically labeled solutions to locate the reaction zones by SIMS. The multiscale characterization of the alteration pattern has allowed proposing alteration mechanisms linked to the properties of the stones and their location inside the building. Moreover, the location of the reactive zones inside the materials determined by the isotopic experiments helps examining the role of the evolution of porosity and formation of alteration products within the material

  7. Rain underscores need for injection

    SciTech Connect

    Stelling, K.F.

    1996-01-01

    Since 1987, steam production totals at The Geysers Geothermal field have fallen and water injection totals have remained quite stable, except for the unusually dry winter months of 1994 when injection fell by a record amount. The heavy rainfall in the first half of 1995 altered the long-term production and injection patterns and underscored the need to increase injection in the field. From January to June 1995, steam production at The Geysers was reduced by 37 percent form the amount produced during the same period in 1994--because the rain increased availability of hydroelectric power. At the same time, water injection in the field rose by 25 percent because more rainwater was available for injection. Consequently, both reservoir pressure and available steam reserves grew, and most power plants that returned on line in the second half of the year produced more megawatts with less steam. This confirmed findings form several injection studies at The Geyser`s.

  8. Golimumab Injection

    MedlinePlus

    ... body and causes pain, swelling, and damage) including: rheumatoid arthritis (condition in which the body attacks its own ... doctor.If golimumab injection is used to treat rheumatoid arthritis, it may also be injected intravenously (into a ...

  9. Adalimumab Injection

    MedlinePlus

    ... causes pain, swelling, and damage) including the following: rheumatoid arthritis (a condition in which the body attacks its ... If you are using adalimumab injection to treat rheumatoid arthritis, your doctor may tell you to inject the ...

  10. Aripiprazole Injection

    MedlinePlus

    ... aripiprazole injection and aripiprazole extended-release injection developed gambling problems or other intense urges or behaviors that ... even if you do not realize that your gambling or any other intense urges or unusual behaviors ...

  11. Teduglutide Injection

    MedlinePlus

    ... mix and inject it.Teduglutide comes as a kit containing vials of teduglutide powder for injection, prefilled syringes containing diluent (liquid to be mixed with teduglutide powder), needles to attach to the diluent syringe, dosing syringes ...

  12. Degarelix Injection

    MedlinePlus

    Degarelix injection is used to treat advanced prostate cancer (cancer that begins in the prostate [a male reproductive gland]). Degarelix injection is in a class of medications called gonadotropin-releasing hormone (GnRH) ...

  13. Cyclosporine Injection

    MedlinePlus

    ... injection is used with other medications to prevent transplant rejection (attack of the transplanted organ by the ... people who have received kidney, liver, and heart transplants. Cyclosporine injection should only be used to treat ...

  14. Colistimethate Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria. Colistimethate injection is in a class of medications called antibiotics. It works by killing bacteria.Antibiotics such as colistimethate injection will not work ...

  15. Chloramphenicol Injection

    MedlinePlus

    ... treat certain types of serious infections caused by bacteria when other antibiotics cannot be used. Chloramphenicol injection ... antibiotics. It works by stopping the growth of bacteria..Antibiotics such as chloramphenicol injection will not work ...

  16. Estrogen Injection

    MedlinePlus

    ... forms of estrogen injection are used to treat hot flushes (hot flashes; sudden strong feelings of heat and sweating) ... If you are using estrogen injection to treat hot flushes, your symptoms should improve within 1 to ...

  17. Medroxyprogesterone Injection

    MedlinePlus

    ... Medroxyprogesterone injection is a very effective method of birth control but does not prevent the spread of human ... you have been using a different method of birth control and are switching to medroxyprogesterone injection, your doctor ...

  18. Etanercept Injection

    MedlinePlus

    ... areas causing pain and joint damage), chronic plaque psoriasis (a skin disease in which red, scaly patches ... etanercept injection is used to treat chronic plaque psoriasis, it may be injected twice a week during ...

  19. Levoleucovorin Injection

    MedlinePlus

    Levoleucovorin injection is used to prevent harmful effects of methotrexate (Rheumatrex, Trexall) when methotrexate is used to to treat certain types of cancer. Levoleucovorin injection is also used to treat people ...

  20. Leucovorin Injection

    MedlinePlus

    Leucovorin injection is used to prevent harmful effects of methotrexate (Rheumatrex, Trexall; cancer chemotherapy medication) when methotrexate is used to to treat certain types of cancer. Leucovorin injection is used to ...

  1. Teniposide Injection

    MedlinePlus

    ... in men. You should not become pregnant or breast-feed while you are receiving teniposide injection. If you or your partner become pregnant while receiving teniposide injection, call your doctor. Teniposide may harm the fetus.

  2. Ipilimumab Injection

    MedlinePlus

    ... are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while receiving ipilimumab injection, call your doctor. Ipilimumab injection may cause your baby to be born too early or to die before birth.

  3. Pralatrexate Injection

    MedlinePlus

    Pralatrexate injection is used to treat peripheral T-cell lymphoma (PTCL; a form of cancer that begins in a ... come back after treatment with other medications. Pralatrexate injection has not been shown to help people who ...

  4. Cyanocobalamin Injection

    MedlinePlus

    Cyanocobalamin injection is used to treat and prevent a lack of vitamin B12 that may be caused by any ... organs) and permanent damage to the nerves. Cyanocobalamin injection also may be given as a test to ...

  5. Paclitaxel Injection

    MedlinePlus

    Paclitaxel injection manufactured with human albumin is used to treat breast cancer that has not improved or that has come back after treatment with other medications. Paclitaxel injection manufactured with polyoxyethylated castor oil is used to ...

  6. Diphenhydramine Injection

    MedlinePlus

    Diphenhydramine injection is used to treat allergic reactions, especially for people who are unable to take diphenhydramine by mouth. ... is used also to treat motion sickness. Diphenhydramine injection is also used alone or along with other ...

  7. Peramivir Injection

    MedlinePlus

    Peramivir injection is used to treat some types of influenza infection ('flu') in people who have had symptoms of ... flu for no longer than 2 days. Peramivir injection is in a class of medications called neuraminidase ...

  8. Cefotetan Injection

    MedlinePlus

    Cefotetan injection is used to treat infections of the lungs, skin, bones, joints, stomach area, blood, female reproductive organs, and urinary tract. Cefotetan injection is also used before surgery to prevent infections. ...

  9. Mipomersen Injection

    MedlinePlus

    Mipomersen injection is used to decrease levels of cholesterol and other fatty substances in the blood in people who ... that removes LDL from the blood), but mipomersen injection should not be used along with this treatment. ...

  10. Romiplostim Injection

    MedlinePlus

    Romiplostim injection is used to increase the number of platelets (cells that help the blood to clot) in order ... low number of platelets in the blood). Romiplostim injection should only be used in people who cannot ...

  11. Hydrocortisone Injection

    MedlinePlus

    Hydrocortisone injection is used to treat symptoms of low corticosteroid levels (lack of certain substances that are usually produced ... also used to treat severe allergic reactions. Hydrocortisone injection is used in the management of multiple sclerosis ( ...

  12. Palivizumab Injection

    MedlinePlus

    Palivizumab injection is used to help prevent respiratory syncytial virus (RSV; common virus that can cause serious lung infections) ... or have certain heart or lung diseases. Palivizumab injection is not used to treat the symptoms of ...

  13. Naltrexone Injection

    MedlinePlus

    Naltrexone injection is used along with counseling and social support to help people who have stopped drinking large amounts of alcohol to avoid drinking again. Naltrexone injection is also used along with counseling and social ...

  14. Tesamorelin Injection

    MedlinePlus

    Tesamorelin injection is used to decrease the amount of extra fat in the stomach area in adults with human ... fat in certain areas of the body). Tesamorelin injection is not used to help with weight loss. ...

  15. Testosterone Injection

    MedlinePlus

    ... and testosterone pellet (Testopel) are forms of testosterone injection used to treat symptoms of low testosterone in ... are low before you begin to use testosterone injection. Testosterone enanthate (Delatestryl) and testosterone pellet (Testopel) are ...

  16. Tigecycline Injection

    MedlinePlus

    Tigecycline injection used to treat certain serious infections including community acquired pneumonia (a lung infection that developed in a ... area between the chest and the waist). Tigecycline injection should not be used to treat pneumonia that ...

  17. Eculizumab Injection

    MedlinePlus

    Eculizumab injection is used to treat paroxysmal nocturnal hemoglobinuria (PNH: a type of anemia in which too many red ... oxygen to all parts of the body). Eculizumab injection is also used to treat atypical hemolytic uremic ...

  18. Pembrolizumab Injection

    MedlinePlus

    Pembrolizumab injection is used to treat melanoma (a type of skin cancer) that cannot be treated with surgery or ... spread to other parts of the body. Pembrolizumab injection is also used to treat a certain type ...

  19. Methylprednisolone Injection

    MedlinePlus

    ... allergic reactions. Methylprednisolone injection is used in the management of multiple sclerosis (a disease in which the ... laboratory test, tell your doctor and the laboratory personnel that you are using methylprednisolone injection.If you ...

  20. Obinutuzumab Injection

    MedlinePlus

    Obinutuzumab injection is used with chlorambucil (Leukeran) to treat chronic lymphocytic leukemia (CLL; a type of cancer of the white blood cells). Obinutuzumab injection is in a class of medications called ...

  1. Busulfan Injection

    MedlinePlus

    Busulfex® Injection ... Busulfan injection is used to treat a certain type of chronic myelogenous leukemia (CML; a type of cancer of ... of 16 doses) before bone marrow transplant.Busulfan injection may cause seizures during therapy with the medication. ...

  2. Limestone dissolution in modeling of slurry scrubbing for flue-gas desulfurization

    SciTech Connect

    Gage, C.L.

    1989-01-01

    Batch limestone dissolution experiments were carried out in a pH stat apparatus at 550C with CO{sub 2} sparging and dissolved sulfite. Particle size distribution, utilization, sulfite in solution, limestone type, and the approach to calcite equilibrium were all found to contribute to the limestone reactivity. In the absence of sulfite limestone dissolution was controlled solely by mass transfer. A surface rate correlation was developed which accounted for observed inhibition by an inverse dependence on calcium sulfite concentration at the limestone surface. A computer code which accounted for mass transfer with surface kinetics was tested against experimental observations of four limestone types. Changes in pH and the concentrations of calcium, carbonate, sulfite, sulfate, and adipic acid were accurately modeled. An overall slurry scrubber model was expanded to predict limestone reactivity from particle size and solution effects. This model predicts scrubber performance and hold tank compositions from the chemistry of the limestone slurry process. Additional subroutines were written to predict particle size distributions from sieve data using the log gamma density function. The expanded model was tested against a limestone type and grind study which investigated utilizations of four limestone types at ten different grinds. The expanded Slurry Scrubber Model was able to predict both SO{sub 2} removal and hold tank compositions of the limestone study. The effects of limestone type were handled through changes in the surface rate parameter. Within a given type the effects of grind and utilization were well modeled.

  3. Quarry Quest. A Field Trip Guide to the Indiana Limestone District, Monroe and Lawrence Counties, Indiana.

    ERIC Educational Resources Information Center

    Shewmaker, Sherman N.

    This guide provides information for planning a field trip to the Indiana Limestone District. This district, located in Monroe and Lawrence Counties, Indiana, is responsible for material that has dominated the building-limestone market in the United States for nearly a century. A few of the many well-known buildings using Indiana limestone are the…

  4. century drying

    NASA Astrophysics Data System (ADS)

    Cook, Benjamin I.; Smerdon, Jason E.; Seager, Richard; Coats, Sloan

    2014-11-01

    Global warming is expected to increase the frequency and intensity of droughts in the twenty-first century, but the relative contributions from changes in moisture supply (precipitation) versus evaporative demand (potential evapotranspiration; PET) have not been comprehensively assessed. Using output from a suite of general circulation model (GCM) simulations from phase 5 of the Coupled Model Intercomparison Project, projected twenty-first century drying and wetting trends are investigated using two offline indices of surface moisture balance: the Palmer Drought Severity Index (PDSI) and the Standardized Precipitation Evapotranspiration Index (SPEI). PDSI and SPEI projections using precipitation and Penman-Monteith based PET changes from the GCMs generally agree, showing robust cross-model drying in western North America, Central America, the Mediterranean, southern Africa, and the Amazon and robust wetting occurring in the Northern Hemisphere high latitudes and east Africa (PDSI only). The SPEI is more sensitive to PET changes than the PDSI, especially in arid regions such as the Sahara and Middle East. Regional drying and wetting patterns largely mirror the spatially heterogeneous response of precipitation in the models, although drying in the PDSI and SPEI calculations extends beyond the regions of reduced precipitation. This expansion of drying areas is attributed to globally widespread increases in PET, caused by increases in surface net radiation and the vapor pressure deficit. Increased PET not only intensifies drying in areas where precipitation is already reduced, it also drives areas into drought that would otherwise experience little drying or even wetting from precipitation trends alone. This PET amplification effect is largest in the Northern Hemisphere mid-latitudes, and is especially pronounced in western North America, Europe, and southeast China. Compared to PDSI projections using precipitation changes only, the projections incorporating both

  5. Hydrogeology and results of injection tests at waste-injection test sites in Pinellas County, Florida

    USGS Publications Warehouse

    Hickey, John J.

    1982-01-01

    Potential benefits or hazards to freshwater resources could result from subsurface injection of treated wastewater. Recognizing this, the U.S. Geological Survey, in cooperation with Pinellas County and the city of St. Petersburg, undertook an evaluation of the hydrogeology and injection of wastewater at proposed test sites on the Pinellas peninsula. The injection sites are underlain by sedimentary rocks ranging in age from Cretaceous to Pleistocene. Lower Eocene carbonate rocks were penetrated to a maximum depth of 3,504 feet and were found to have relatively low water yields. The most permeable part of the investigated section was in rocks of middle Eocene age within the Floridan aquifer. At the injection sites, the Floridan aquifer was subdivided into four permeable zones and three semiconfining beds. The test injection zone is within the Avon Park Limestone, the most productive of the identified permeable zones, with a transmissivity of about 1,000,000 feet squared per day. Two semiconfining beds are above the injection zone in the Suwannee Limestone and Ocala Limestone and have vertical hydraulic conductivities estimated to range from about 0.1 to 1 foot per day where these beds do not contain clay. Limited fresh ground-water supplies exist in the Floridan aquifer within the Pinellas peninsula. At all test sites, chloride concentration in the injection zone ranged from 19,000 to 20,000 milligrams per liter. Injection tests ranging in duration from 3 to 91.1 days were run at three different sites. Pressure buildup occurred in permeable zones above and below the injection zone during these tests. Calculated pressure buildup in observation wells close to and at some distance from the test wells was typically less than 1 pound per square inch. Injection and formation water will probably move slowly through the semiconfining bed overlying the injection zone, and long-term injection tests will be needed to determine the effectiveness of these beds to retard flow. The

  6. Characterization of limestone reacted with acid-mine drainage in a pulsed limestone bed treatment system at the Friendship Hill National Historical Site, Pennsylvania, USA

    USGS Publications Warehouse

    Hammarstrom, J.M.; Sibrell, P.L.; Belkin, H.E.

    2003-01-01

    Armoring of limestone is a common cause of failure in limestone-based acid-mine drainage (AMD) treatment systems. Limestone is the least expensive material available for acid neutralization, but is not typically recommended for highly acidic, Fe-rich waters due to armoring with Fe(III) oxyhydroxide coatings. A new AMD treatment technology that uses CO2 in a pulsed limestone bed reactor minimizes armor formation and enhances limestone reaction with AMD. Limestone was characterized before and after treatment with constant flow and with the new pulsed limestone bed process using AMD from an inactive coal mine in Pennsylvania (pH = 2.9, Fe = 150 mg/l, acidity = 1000 mg/l CaCO3). In constant flow experiments, limestone is completely armored with reddish-colored ochre within 48 h of contact in a fluidized bed reactor. Effluent pH initially increased from the inflow pH of 2.9 to over 7, but then decreased to 6 during operation. Limestone removed from a pulsed bed pilot plant is a mixture of unarmored, rounded and etched limestone grains and partially armored limestone and refractory mineral grains (dolomite, pyrite). The ???30% of the residual grains in the pulsed flow reactor that are armored have thicker (50- to 100-??m), more aluminous coatings and lack the gypsum rind that develops in the constant flow experiment. Aluminium-rich zones developed in the interior parts of armor rims in both the constant flow and pulsed limestone bed experiments in response to pH changes at the solid/solution interface. ?? 2003 Elsevier Ltd. All rights reserved.

  7. Performance of portland limestone cements: Cements designed to be more sustainable that include up to 15% limestone addition

    NASA Astrophysics Data System (ADS)

    Barrett, Timothy J.

    In 2009, ASTM and AASHTO permitted the use of up to 5% interground limestone in ordinary portland cement (OPC) as a part of a change to ASTM C150/AASHTO M85. When this work was initiated a new proposal was being discussed that would enable up to 15% interground limestone cement to be considered in ASTM C595/AASHTO M234. This work served to provide rapid feedback to the state department of transportation and concrete industry for use in discussions regarding these specifications. Since the time this work was initiated, ASTM C595/AASHTO M234 was passed (2012c) and PLCs are now able to be specified, however they are still not widely used. The proposal for increasing the volume of limestone that would be permitted to be interground in cement is designed to enable more sustainable construction, which may significantly reduce the CO2 that is embodied in the built infrastructure while also extending the life of cement quarries. Research regarding the performance of cements with interground limestone has been conducted by the cement industry since these cements became widely used in Europe over three decades ago, however this work focuses on North American Portland Limestone Cements (PLCs) which are specifically designed to achieve similar performance as the OPCs they replace.This thesis presents a two-phase study in which the potential for application of cements containing limestone was assessed. The first phase of this study utilized a fundamental approach to determine whether cement with up to 15% of interground or blended limestone can be used as a direct substitute to ordinary portland cement. The second phase of the study assessed the concern of early age shrinkage and cracking potential when using PLCs, as these cements are typically ground finer than their OPC counterparts. For the first phase of the study, three commercially produced PLCs were obtained and compared to three commercially produced OPCs made from the same clinker. An additional cement was tested

  8. Dry cell battery poisoning

    MedlinePlus

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  9. Preservation of York Minster historic limestone by hydrophobic surface coatings

    PubMed Central

    Walker, Rachel A.; Wilson, Karen; Lee, Adam F.; Woodford, Julia; Grassian, Vicki H.; Baltrusaitis, Jonas; Rubasinghege, Gayan; Cibin, Giannantonio; Dent, Andrew

    2012-01-01

    Magnesian limestone is a key construction component of many historic buildings that is under constant attack from environmental pollutants notably by oxides of sulfur via acid rain, particulate matter sulfate and gaseous SO2 emissions. Hydrophobic surface coatings offer a potential route to protect existing stonework in cultural heritage sites, however, many available coatings act by blocking the stone microstructure, preventing it from ‘breathing' and promoting mould growth and salt efflorescence. Here we report on a conformal surface modification method using self-assembled monolayers of naturally sourced free fatty acids combined with sub-monolayer fluorinated alkyl silanes to generate hydrophobic (HP) and super hydrophobic (SHP) coatings on calcite. We demonstrate the efficacy of these HP and SHP surface coatings for increasing limestone resistance to sulfation, and thus retarding gypsum formation under SO2/H2O and model acid rain environments. SHP treatment of 19th century stone from York Minster suppresses sulfuric acid permeation. PMID:23198088

  10. EFFECT OF AN ACID RAIN ENVIRONMENT ON LIMESTONE SURFACES.

    USGS Publications Warehouse

    Mossotti, Victor G.; Lindsay, James R.; Hochella, Michael F.

    1987-01-01

    Salem limestone samples were exposed to weathering for 1 y in several urban and one rural environments. Samples exposed in the rural location were chemically indistinguishable from the freshly quarried limestone, whereas all samples collected from urban exposure sites developed gypsum stains on the ground-facing surfaces where the stones were not washed by precipitation. The gas-solid reaction of SO//2 with calcite was selected for detailed consideration. It appears from the model that under arid conditions, the quantity of stain deposited on an unwashed surface is independent of atmospheric SO//2 concentration once the surface has been saturated with gypsum. Under wet conditions, surface sulfation and weight loss are probably dominated by mechanisms involving wet stone. However, if the rain events are frequent and delimited by periods of dryness, the quantity of gypsum produced by a gas-solid reaction mechanism should correlate with both the frequency of rain events and the atmospheric SO//2 level.

  11. Background radiation measurements at 2200 ft depth in limestone mine.

    NASA Astrophysics Data System (ADS)

    Olling Back, Henning; Vogelaar, R. Bruce; Johnson, D. Nathan

    2003-10-01

    An active limestone mine in southwestern Virginia is being investigated as a possible site for detectors requiring a low muon flux. The current depth of the mine is 2200 feet. However, the mining operations continue to follow a vain of pure limestone at a 30-degree downward plane under a rising escarpment, and so greater depths can be achieved relatively quickly. With over 50 miles of drifts, many 100 ft high and 40 ft wide, and drive in access, this is a potential venue for future low background detectors. We will be reporting initial measurements of the muon flux as a function of zenith angle, as well as the ambient gamma radiation from the surrounding rock.

  12. Preservation of York Minster historic limestone by hydrophobic surface coatings

    NASA Astrophysics Data System (ADS)

    Walker, Rachel A.; Wilson, Karen; Lee, Adam F.; Woodford, Julia; Grassian, Vicki H.; Baltrusaitis, Jonas; Rubasinghege, Gayan; Cibin, Giannantonio; Dent, Andrew

    2012-11-01

    Magnesian limestone is a key construction component of many historic buildings that is under constant attack from environmental pollutants notably by oxides of sulfur via acid rain, particulate matter sulfate and gaseous SO2 emissions. Hydrophobic surface coatings offer a potential route to protect existing stonework in cultural heritage sites, however, many available coatings act by blocking the stone microstructure, preventing it from `breathing' and promoting mould growth and salt efflorescence. Here we report on a conformal surface modification method using self-assembled monolayers of naturally sourced free fatty acids combined with sub-monolayer fluorinated alkyl silanes to generate hydrophobic (HP) and super hydrophobic (SHP) coatings on calcite. We demonstrate the efficacy of these HP and SHP surface coatings for increasing limestone resistance to sulfation, and thus retarding gypsum formation under SO2/H2O and model acid rain environments. SHP treatment of 19th century stone from York Minster suppresses sulfuric acid permeation.

  13. Cement substitution by a combination of metakaolin and limestone

    SciTech Connect

    Antoni, M.; Rossen, J.; Martirena, F.; Scrivener, K.

    2012-12-15

    This study investigates the coupled substitution of metakaolin and limestone in Portland cement (PC). The mechanical properties were studied in mortars and the microstructural development in pastes by X-ray diffraction, thermogravimetry analysis, mercury intrusion porosimetry and isothermal calorimetry. We show that 45% of substitution by 30% of metakaolin and 15% of limestone gives better mechanical properties at 7 and 28 days than the 100% PC reference. Our results show that calcium carbonate reacts with alumina from the metakaolin, forming supplementary AFm phases and stabilizing ettringite. Using simple mass balance calculations derived from thermogravimetry results, we also present the thermodynamic simulation for the system, which agrees fairly well with the experimental observations. It is shown that gypsum addition should be carefully balanced when using calcined clays because it considerably influences the early age strength by controlling the very rapid reaction of aluminates.

  14. Pneumatic conveying of coal and coal-limestone mixtures as applied to atmospheric fluidized-bed combustion. [Effects of moisture, velocity, particle size

    SciTech Connect

    Daw, C. S.; Thomas, J. F.

    1982-01-01

    Pneumatic conveying experiments with coal and coal-limestone mixtures were performed on a conveying system designed to represent the feed lines in the Tennessee Valley Authority 20 MW atmospheric fluidized bed combustor. The experimental conditions were chosen to cover the anticipated combustor operating ranges. The results have led to a fundamental understanding of the operating limits associated with coal surface moisture, air velocity, coal and limestone fines, solids to air ratio, and limestone to coal ratio. Coal surface moisture was found to be the most important parameter affecting handling and transport. Specific upper limits for surface moisture were established. It was demonstrated that addition of dry limestone can reduce the conveying problems associated with wet coal. The air velocities causing saltation and surge flow were determined for a variety of conveying conditions. These velocities were related qualitatively to solids to air ratio, particle size, and surface moisture. Conveying pressure drop was also measured for a variety of conditions. In the absence of saltation, the horizontal, frictional pressure drop was only a function of the solids to air ratio and the air flow conditions. Comparison of the ORNL pressure drop data with the results of other investigators had led to the conclusion that there are two basic modes of flow in dilute-phase conveying; a primarily viscous mode and a primarily inertial mode. A general pressure drop model has been developed for the inertial mode.

  15. Long-term calcination/carbonation cycling and thermal pretreatment for CO{sub 2} capture by limestone and dolomite

    SciTech Connect

    Zhongxiang Chen; Hoon Sub Song; Miguel Portillo; C. Jim Lim; John R. Grace; E.J. Anthony

    2009-03-15

    Capturing carbon dioxide is vital for the future of climate-friendly combustion, gasification, and steam-re-forming processes. Dry processes utilizing simple sorbents have great potential in this regard. Long-term calcination/carbonation cycling was carried out in an atmospheric-pressure thermogravimetric reactor. Although dolomite gave better capture than limestone for a limited number of cycles, the advantage declined over many cycles. Under some circumstances, decreasing the carbonation temperature increased the rate of reaction because of the interaction between equilibrium and kinetic factors. Limestone and dolomite, after being pretreated thermally at high temperatures (1000 or 1100{sup o}C), showed a substantial increase in calcium utilization over many calcination/carbonation cycles. Lengthening the pretreatment interval resulted in greater improvement. However, attrition was significantly greater for the pretreated sorbents. Greatly extending the duration of carbonation during one cycle was found to be capable of restoring the CO{sub 2} capture ability of sorbents to their original behavior, offering a possible means of countering the long-term degradation of calcium sorbents for dry capture of carbon dioxide. 12 refs., 12 figs., 2 tabs.

  16. Time-Dependent Rock Failure in a Heterogeneous Limestone

    NASA Astrophysics Data System (ADS)

    Roth, K.; Kemeny, J.

    2015-12-01

    Time-dependent rock failure is an important aspect in the analysis of long-term rock stability for slopes, dam and bridge foundations, and underground storage facilities. An on-going project at the University of Arizona is using Kartchner Caverns in Benson, Arizona as a natural analog to study such failure by reconstructing the process of natural cave breakdown with subcritical crack growth modeling. Breakdown is thought to occur along joints through the time-dependent failure of rock bridges: sections of intact rock separating discontinuities in a rock mass. The Escabrosa limestone composing the caverns ranges from a more homogenous, even-grained texture to a more heterogeneous texture consisting of coarse-grained veins and solution cavities set in a fine-grained matrix. To determine if the veined regions are more susceptible to fracturing and act as the nuclei of rock bridge failure, fracture toughness tests were conducted for both textures. The subcritical crack growth parameters were calculated using the constant stress-rate method. Results indicate that the more heterogeneous limestone has a higher fracture strength, fracture toughness, and subcritical crack growth index n than the more homogeneous limestone. This is in agreement with previous studies which found that a more complex and heterogeneous microstructure produces a larger microcrack process zone, leading to higher fracture energies and lower susceptibility to subcritical crack growth. Thus, despite their solution cavities, the calcite veins do not localize failure or act as planes of weakness; instead, rock bridges fail through the more homogeneous limestone matrix.

  17. Dolomitization of Quaternary reef limestones, Aitutaki, Cook Islands

    USGS Publications Warehouse

    Hein, J.R.; Gray, S.C.; Richmond, B.M.; White, L.D.

    1992-01-01

    The primary reef framework is considered to have been deposited during several highstands of sea level. Following partial to local recrystallization of the limestone, a signle episode of dolomitization occurred. Both tidal and thermal pumping drove large quantities of seawater through the porous rocks and perhaps maintained a wide mixing zone. However, the isotopic, geochemical and petrographic data do not clearly indicate the extent of seawater mixing. -from Authors

  18. Modeling of SO{sub 2} absorption into limestone suspensions

    SciTech Connect

    Lancia, A.; Musmarra, D.; Pepe, F.

    1997-01-01

    The wet limestone flue gas desulfurization process, and more specifically absorption of SO{sub 2} limestone suspensions, was studied. Experiments of SO{sub 2} absorption were carried out using a bubbling reactor with a mixture of sulfur dioxide and nitrogen in the gas phase and an aqueous limestone suspension in the liquid phase. The SO{sub 2} absorption rate was measured at different compositions of both gas and liquid phases and at different gas flow rates and agitator speeds. A model based on the film theory was proposed to describe liquid-side mass transfer. It was assumed that the liquid-phase diffusional resistance is concentrated in a layer, the thickness of which depends on fluid dynamics, but is independent of the nature of the reactions taking place. The equations considered by the model describe conditions of thermodynamic equilibrium as well as material and electrical balances and use the experimentally determined gas- and liquid-side mass-transfer coefficients, rather than empirical parameters. Model calculations and experimental results were compared, and a good consistency was found. Eventually the model was used to evaluate the absorption enhancement factor as a function of gas- and liquid-phase composition.

  19. Stratigraphy of the Upper Pleistocene Miami Limestone of Florida

    SciTech Connect

    Johnson, R.A.

    1993-03-01

    The upper Pleistocene Miami Limestone is probably the most stratigraphically-complex formation in the Cenozoic of Florida. The Miami overlies and vertically/laterally grades into the upper Pleistocene Ft. Thompson Formation to the west in southeast Palm Beach County (west of I-95); to the west in Broward County (west of the Turnpike); and to the north in south Broward County (along U.S. 27). The Miami overlies and very locally vertically grades into the Ft. Thompson in all of Dade County. The Miami overlies and vertically/laterally grades into the upper Pleistocene Anastasia Formation to the north and east in southeast Palm Beach County (east of I-95), and to the northeast in east Broward County (east of the Turnpike). The Miami laterally grades into the upper Pleistocene Key Largo Limestone to the southeast in extreme southeast Dade County, and overlies and locally vertically grades into the Key Largo in the Lower Keys, south Monroe County. The Miami unconformably overlies the Pliocene Tamiami Formation and pinches out to the west in northeast mainland Monroe and southeast Collier Counties, and also pinches out to the north in east-central Palm Beach County. In all areas, the Miami Limestone is either overlain unconformably by very discontinuous undifferentiated surficial sediments or forms land surface.

  20. Laboratory Investigations in Support of Dioxide-Limestone Sequestration in the Ocean

    SciTech Connect

    Dan Golomb; Eugene Barry; David Ryan; Stephen Pennell; Carl Lawton; Peter Swett; Devinder Arora; John Hannon; Michael Woods; Huishan Duan; Tom Lawlor

    2008-09-30

    Research under this Project has proven that liquid carbon dioxide can be emulsified in water by using very fine particles as emulsion stabilizers. Hydrophilic particles stabilize a CO{sub 2}-in-H{sub 2}O (C/W) emulsion; hydrophobic particles stabilize a H{sub 2}O-in-CO{sub 2} (W/C) emulsion. The C/W emulsion consists of tiny CO{sub 2} droplets coated with hydrophilic particles dispersed in water. The W/C emulsion consists of tiny H{sub 2}O droplets coated with hydrophobic particles dispersed in liquid carbon dioxide. The coated droplets are called globules. The emulsions could be used for deep ocean sequestration of CO{sub 2}. Liquid CO{sub 2} is sparsely soluble in water, and is less dense than seawater. If neat, liquid CO{sub 2} were injected in the deep ocean, it is likely that the dispersed CO{sub 2} droplets would buoy upward and flash into vapor before the droplets dissolve in seawater. The resulting vapor bubbles would re-emerge into the atmosphere. On the other hand, the emulsion is denser than seawater, hence the emulsion plume would sink toward greater depth from the injection point. For ocean sequestration a C/W emulsion appears to be most practical using limestone (CaCO{sub 3}) particles of a few to ten ?m diameter as stabilizing agents. A mix of one volume of liquid CO{sub 2} with two volumes of H{sub 2}O, plus 0.5 weight of pulverized limestone per weight of liquid CO{sub 2} forms a stable emulsion with density 1087 kg m{sup -3}. Ambient seawater at 500 m depth has a density of approximately 1026 kg m{sup -3}, so the emulsion plume would sink by gravity while entraining ambient seawater till density equilibrium is reached. Limestone is abundant world-wide, and is relatively cheap. Furthermore, upon disintegration of the emulsion the CaCO{sub 3} particles would partially buffer the carbonic acid that forms when CO{sub 2} dissolves in seawater, alleviating some of the concerns of discharging CO{sub 2} in the deep ocean. Laboratory experiments showed

  1. Thermo-poroelastic response of an argillaceous limestone

    NASA Astrophysics Data System (ADS)

    Selvadurai, Patrick; Najari, Meysam

    2016-04-01

    Argillaceous limestones are now being considered by many countries that intend to develop deep geologic storage facilities for siting both high-level and intermediate- to low-level nuclear fuel wastes. In deep geologic settings for high level nuclear wastes, the heating due to radioactive decay is transmitted through an engineered barrier, which consists of the waste container and an engineered geologic barrier, which consists of an encapsulating compacted bentonite. The heat transfer process therefore leads to heating of the rock mass where the temperature of the rock is substantially lower than the surface temperature of the waste container. This permits the use of mathematical theories of poroelastic media where phase transformations, involving conversion of water to a vapour form are absent. While the thermo-poroelastic responses of geologic media such as granite and porous tuff have been investigated in the literature, the investigation of thermo-poroelastic responses of argillaceous limestones is relatively new. Argillaceous limestones are considered to be suitable candidates for siting deep geologic repositories owing to the ability to accommodate stress states with generation of severe defects that can influence their transmissivity characteristics. Also the clay fraction in such rocks can contribute to long term healing type phenomena, which is a considerable advantage. This research presents the results of a laboratory investigation and computational modelling of the same that examines the applicability of the theory of thermo-poroelasticity, which extend Biot's classical theory of poroelasticity to include uncoupled heat conduction. The experimental configuration involves the boundary heating of a cylinder of the Cobourg Limestone from southern Ontario, Canada. The cylinder measuring 150 mm in diameter and 278 mm in length contains an axisymmetric fluid-filled cylindrical cavity measuring 26 mm in diameter and 139 mm in length. Thermo-poroelastic effects

  2. Colorful drying.

    PubMed

    Lakio, Satu; Heinämäki, Jyrki; Yliruusi, Jouko

    2010-03-01

    Drying is one of the standard unit operations in the pharmaceutical industry and it is important to become aware of the circumstances that dominate during the process. The purpose of this study was to test microcapsulated thermochromic pigments as heat indicators in a fluid bed drying process. The indicator powders were manually granulated with alpha-lactose monohydrate resulting in three particle-size groups. Also, pellets were coated with the indicator powders. The granules and pellets were fluidized in fluid bed dryer to observe the progress of the heat flow in the material and to study the heat indicator properties of the indicator materials. A tristimulus colorimeter was used to measure CIELAB color values. Color indicator for heat detection can be utilized to test if the heat-sensitive API would go through physical changes during the pharmaceutical drying process. Both the prepared granules and pellets can be used as heat indicator in fluid bed drying process. The colored heat indicators give an opportunity to learn new aspects of the process at real time and could be exploded, for example, for scaling-up studies.

  3. Musculoskeletal Injection

    PubMed Central

    Wittich, Christopher M.; Ficalora, Robert D.; Mason, Thomas G.; Beckman, Thomas J.

    2009-01-01

    Patients commonly present to primary care physicians with musculoskeletal symptoms. Clinicians certified in internal medicine must be knowledgeable about the diagnosis and management of musculoskeletal diseases, yet they often receive inadequate postgraduate training on this topic. The musculoskeletal problems most frequently encountered in our busy injection practice involve, in decreasing order, the knees, trochanteric bursae, and glenohumeral joints. This article reviews the clinical presentations of these problems. It also discusses musculoskeletal injections for these problems in terms of medications, indications, injection technique, and supporting evidence from the literature. Experience with joint injection and the pharmacological principles described in this article should allow primary care physicians to become comfortable and proficient with musculoskeletal injections. PMID:19720781

  4. Selected Data for Wells and Test Holes Used in Structure-Contour Maps of the Inyan Kara Group, Minnekahta Limestone, Minnelusa Formation, Madison Limestone, and Deadwood Formation in the Black Hills Area, South Dakota

    DTIC Science & Technology

    1999-01-01

    Selected Data for Wells and Test Holes Used in Structure-Contour Maps of the Inyan Kara Group, Minnekahta Limestone, Minnelusa Formation, Madison...Test Holes Used in Structure-Contour Maps of the Inyan Kara Group, Minnekahta Limestone, Minnelusa Formation, Madison Limestone, and Deadwood Formation...Structure-Contour Maps of the Inyan Kara Group, Minnekahta Limestone, Minnelusa Formation, Madison Limestone, and Deadwood Formation in the Black Hills Area

  5. 21 CFR 522.2424 - Sodium thiamylal for injection.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... § 522.2424 Sodium thiamylal for injection. (a) Specifications. The drug is a sterile dry powder. It is reconstituted aseptically with sterile distilled water, water for injection, or sodium chloride injection, to a... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Sodium thiamylal for injection. 522.2424...

  6. Biotin- and Glycoprotein-Coated Microspheres as Surrogates for Studying Filtration Removal of Cryptosporidium parvum in a Granular Limestone Aquifer Medium.

    PubMed

    Stevenson, M E; Blaschke, A P; Toze, S; Sidhu, J P S; Ahmed, W; van Driezum, I H; Sommer, R; Kirschner, A K T; Cervero-Aragó, S; Farnleitner, A H; Pang, L

    2015-07-01

    Members of the genus Cryptosporidium are waterborne protozoa of great health concern. Many studies have attempted to find appropriate surrogates for assessing Cryptosporidium filtration removal in porous media. In this study, we evaluated the filtration of Cryptosporidium parvum in granular limestone medium by the use of biotin- and glycoprotein-coated carboxylated polystyrene microspheres (CPMs) as surrogates. Column experiments were carried out with core material taken from a managed aquifer recharge site in Adelaide, Australia. For the experiments with injection of a single type of particle, we observed the total removal of the oocysts and glycoprotein-coated CPMs, a 4.6- to 6.3-log10 reduction of biotin-coated CPMs, and a 2.6-log10 reduction of unmodified CPMs. When two different types of particles were simultaneously injected, glycoprotein-coated CPMs showed a 5.3-log10 reduction, while the uncoated CPMs displayed a 3.7-log10 reduction, probably due to particle-particle interactions. Our results confirm that glycoprotein-coated CPMs are the most accurate surrogates for C. parvum; biotin-coated CPMs are slightly more conservative, while unmodified CPMs are markedly overly conservative for predicting C. parvum removal in granular limestone medium. The total removal of C. parvum observed in our study suggests that granular limestone medium is very effective for the filtration removal of C. parvum and could potentially be used for the pretreatment of drinking water and aquifer storage recovery of recycled water.

  7. Biotin- and Glycoprotein-Coated Microspheres as Surrogates for Studying Filtration Removal of Cryptosporidium parvum in a Granular Limestone Aquifer Medium

    PubMed Central

    Blaschke, A. P.; Toze, S.; Sidhu, J. P. S.; Ahmed, W.; van Driezum, I. H.; Sommer, R.; Kirschner, A. K. T.; Cervero-Aragó, S.; Farnleitner, A. H.; Pang, L.

    2015-01-01

    Members of the genus Cryptosporidium are waterborne protozoa of great health concern. Many studies have attempted to find appropriate surrogates for assessing Cryptosporidium filtration removal in porous media. In this study, we evaluated the filtration of Cryptosporidium parvum in granular limestone medium by the use of biotin- and glycoprotein-coated carboxylated polystyrene microspheres (CPMs) as surrogates. Column experiments were carried out with core material taken from a managed aquifer recharge site in Adelaide, Australia. For the experiments with injection of a single type of particle, we observed the total removal of the oocysts and glycoprotein-coated CPMs, a 4.6- to 6.3-log10 reduction of biotin-coated CPMs, and a 2.6-log10 reduction of unmodified CPMs. When two different types of particles were simultaneously injected, glycoprotein-coated CPMs showed a 5.3-log10 reduction, while the uncoated CPMs displayed a 3.7-log10 reduction, probably due to particle-particle interactions. Our results confirm that glycoprotein-coated CPMs are the most accurate surrogates for C. parvum; biotin-coated CPMs are slightly more conservative, while unmodified CPMs are markedly overly conservative for predicting C. parvum removal in granular limestone medium. The total removal of C. parvum observed in our study suggests that granular limestone medium is very effective for the filtration removal of C. parvum and could potentially be used for the pretreatment of drinking water and aquifer storage recovery of recycled water. PMID:25888174

  8. Weight losses of marble and limestone briquettes exposed to outdoor environment in the eastern United States: Results of exposure 1988--1992

    SciTech Connect

    Reimann, K.J.

    1995-04-01

    Monitoring continued on weight changes in marble and limestone briquettes exposed to the outdoor environment at sites in the eastern US. This report presents data for the exposure period 1988--1992 and summarizes results for the entire period from 1984. Since 1989, only three exposure sites have remained active, but briquettes from preexposed material were added at those sites. A linear relationship was found between cumulative gravimetric losses and exposure period. These losses resulted in an average recession rate of 11 to 21 {micro}m/yr for marble and 21 to 45 {micro}m/yr for limestone. The recession rates are site-dependent and can be described with respect to rain depth and other atmospheric conditions, as evidenced by the very low rates at the Ohio site on the movable rack, dry regime. Weight monitoring is continuing in a planned 10-year program.

  9. Penetration into limestone targets with ogive-nose steel projectiles

    SciTech Connect

    Frew, D.J.; Green, M.L.; Forrestal, M.J.; Hanchak, S.J.

    1996-12-01

    We conducted depth of penetration experiments into limestone targets with 3.0 caliber-radius-head, 4340 Rc 45 steel projectiles. Powder guns launched two projectiles with length-to-diameter ratios of ten to striking velocities between 0.4 and 1.5 km/s. Projectiles had diameters and masses of 12.7 mm, 0. 117 kg and 25.4 mm, 0.610 kg. Based on data sets with these two projectile scales, we proposed an empirical penetration equation that described the target by its density and an empirical strength constant determined from penetration depth versus striking velocity data.

  10. Elucidation of denitrification mechanism in karstic Ryukyu limestone aquifer

    NASA Astrophysics Data System (ADS)

    Hijikawa, K.

    2014-12-01

    Nitrate (NO3-) concentrations in public water supplies have risen above acceptable levels in many areas of the world including Japan, largely as a result of contamination by human and animal waste and overuse of fertilizers. A previous study has characterized nitrate concentrations in groundwater in this area is a higher than the upper value (44mgL-1) of environmental quality criteria on one hands. On the other hand, there exists points where the concentration of nitric acid is not detected, which suggests the possibility of denitrification. During early 2000, a new analytical procedure for nitrate isotopic measurement, termed the "denitrifier method", was established. With the development of the nitrate isotope tracer method, much research has been reported detailing sources of groundwater nitrate and denitrification mechanisms. This study presents a pilot case study (in the southern part of Okinawa Main Island, Japan, where Ryukyu limestone is extensively distributed) using the combined stable isotope ratios of major elements (C, N and S) as net recorders of the biogeochemical reactions with the aim of elucidation of denitrification mechanism in Ryukyu limestone aquifer. As a result, significant decreases in nitrate concentrations due to denitrification were observed in groundwater at some locations, which induced increases in isotope ratios up to 59.7‰ for δ15NNO3. These points of groundwater were located above the cutoff wall of the underground dam and near the fault. It is considered that the residence time of the groundwater is longer than the other points at these denitrification points, and that reduction condition tends to be formed in the groundwater. However, the rapid rise of the groundwater level due to rainfall is likely to occur in the Ryukyu limestone aquifer, where the ground water was found to have changed dynamically from the reduction condition to the oxidation condition which a denitrification (has not occured)does not occur. Moreover, the

  11. Certolizumab Injection

    MedlinePlus

    ... has not improved when treated with other medications, rheumatoid arthritis (a condition in which the body attacks its ... continues. When certolizumab injection is used to treat rheumatoid arthritis, it is usually given every other week and ...

  12. Natalizumab Injection

    MedlinePlus

    ... prevent episodes of symptoms in people who have Crohn's disease (a condition in which the body attacks the ... If you are receiving natalizumab injection to treat Crohn's disease, your symptoms should improve during the first few ...

  13. Vedolizumab Injection

    MedlinePlus

    ... injection may cause serious allergic reactions during an infusion and for several hours afterward. A doctor or ... of the following symptoms during or after your infusion: rash; itching; swelling of the face, eyes, mouth, ...

  14. Panitumumab Injection

    MedlinePlus

    ... as a solution (liquid) to be given by infusion (injected into a vein). It is usually given ... doctor or nurse in a doctor's office or infusion center. Panitumumab is usually given once every 2 ...

  15. Methotrexate Injection

    MedlinePlus

    ... woman's uterus while she is pregnant), breast cancer, lung cancer, certain cancers of the head and neck; certain ... Methotrexate injection is also used along with rest, physical therapy and ... treat rheumatoid arthritis by decreasing the activity of the immune system.

  16. Alirocumab Injection

    MedlinePlus

    ... injection is used along with diet and certain cholesterol-lowering medications (HMG-CoA reductase inhibitors [statins]) in ... familial heterozygous hypercholesterolemia (an inherited condition in which cholesterol cannot be removed from the body normally) or ...

  17. Evolocumab Injection

    MedlinePlus

    ... injection is used along with diet and certain cholesterol-lowering medications, HMG-CoA reductase inhibitors (statins), in ... heterozygous hypercholesterolemia (HeFH; an inherited condition in which cholesterol cannot be removed from the body normally) or ...

  18. Pentamidine Injection

    MedlinePlus

    Pentamidine injection is used to treat pneumonia caused by a fungus called Pneumocystis carinii. It is in a class of medications called antiprotozoals. It works by stopping the growth of protozoa that can cause pneumonia.

  19. Oxytocin Injection

    MedlinePlus

    Oxytocin injection is used to begin or improve contractions during labor. Oxytocin also is used to reduce bleeding after childbirth. ... other medications or procedures to end a pregnancy. Oxytocin is in a class of medications called oxytocic ...

  20. Ibritumomab Injection

    MedlinePlus

    ... is in a class of medications called monoclonal antibodies with radioisotopes. It works by attaching to cancer ... you receive ibritumomab injection, your body may develop antibodies (substances in the blood that help the immune ...

  1. Ganciclovir Injection

    MedlinePlus

    ... problems, eye problems other than CMV retinitis, or kidney disease.tell your doctor if you are pregnant or plan to become pregnant. Ganciclovir injection may cause infertility (difficulty becoming pregnant). However, if you are a ...

  2. Bendamustine Injection

    MedlinePlus

    ... a type of cancer of the white blood cells). Bendamustine injection is also used to treat a ... that begins in a type of white blood cell that normally fights infection) that is slow spreading, ...

  3. Vancomycin Injection

    MedlinePlus

    ... medications called glycopeptide antibiotics. It works by killing bacteria that cause infections.Antibiotics such as vancomycin injection ... infection may not be completely treated and the bacteria may become resistant to antibiotics.

  4. Levofloxacin Injection

    MedlinePlus

    ... of antibiotics called fluoroquinolones. It works by killing bacteria that cause infections.Antibiotics such as levofloxacin injection ... infection may not be completely treated and the bacteria may become resistant to antibiotics.

  5. Doxycycline Injection

    MedlinePlus

    ... medications called tetracycline antibiotics. It works by killing bacteria that cause infections.Antibiotics such as doxycycline injection ... infection may not be completely treated and the bacteria may become resistant to antibiotics.

  6. Sumatriptan Injection

    MedlinePlus

    ... accompanied by nausea and sensitivity to sound and light). Sumatriptan injection is also used to treat the ... children. Store it at room temperature, away from light, excess heat, and moisture (not in the bathroom). ...

  7. Alemtuzumab Injection

    MedlinePlus

    ... injection, the medication is usually given three times weekly on alternate days (usually Monday, Wednesday, and Friday) ... that you eat foods that are rich in iron such as meats, leafy green vegetables, and fortified ...

  8. Epinephrine Injection

    MedlinePlus

    Epinephrine injection is used along with emergency medical treatment to treat life-threatening allergic reactions caused by ... or stings, foods, medications, latex, and other causes. Epinephrine is in a class of medications called alpha- ...

  9. Mitoxantrone Injection

    MedlinePlus

    ... medications to relieve pain in people with advanced prostate cancer who did not respond to other medications. Mitoxantrone ... doses). When mitoxantrone injection is used to treat prostate cancer, it is usually given once every 21 days. ...

  10. Trastuzumab Injection

    MedlinePlus

    ... with other medications to treat certain types of stomach cancer that have spread to other parts of the ... weeks. When trastuzumab injection is used to treat stomach cancer, it is usually given once every 3 weeks. ...

  11. Topotecan Injection

    MedlinePlus

    ... organs where eggs are formed) and small cell lung cancer (a type of cancer that begins in the ... topotecan injection is used to treat ovarian or lung cancer, it is usually given once a day for ...

  12. Palonosetron Injection

    MedlinePlus

    ... that may occur several days after receiving certain chemotherapy medications. Palonosetron injection is in a class of medications called 5-HT3 receptor antagonists. It works by blocking the action of serotonin, a natural ...

  13. Meropenem Injection

    MedlinePlus

    ... skin and abdominal (stomach area) infections caused by bacteria and meningitis (infection of the membranes that surround ... of medications called antibiotics. It works by killing bacteria that cause infection.Antibiotics such as meropenem injection ...

  14. Amikacin Injection

    MedlinePlus

    ... treat certain serious infections that are caused by bacteria such as meningitis (infection of the membranes that ... medications called aminoglycoside antibiotics. It works by killing bacteria.Antibiotics such as amikacin injection will not work ...

  15. Ertapenem Injection

    MedlinePlus

    ... abdominal (stomach area) infections, that are caused by bacteria. It is also used for the prevention of ... medications called carbapenem antibiotics. It works by killing bacteria.Antibiotics such as ertapenem injection will not work ...

  16. Moxifloxacin Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria such as pneumonia; ; and , skin, and abdominal (stomach ... antibiotics called fluoroquinolones. It works by killing the bacteria that cause infections.Antibiotics such as moxifloxacin injection ...

  17. Cefepime Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria including pneumonia, and skin, urinary tract, and kidney ... medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefepime injection will not work ...

  18. Cefazolin Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria including skin, bone, joint, genital, blood, heart valve, ... medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefazolin injection will not work ...

  19. Daptomycin Injection

    MedlinePlus

    ... blood infections or serious skin infections caused by bacteria. Daptomycin injection is in a class of medications called cyclic lipopeptide antibiotics. It works by killing bacteria. Antibiotics will not work for treating colds, flu, ...

  20. Aztreonam Injection

    MedlinePlus

    ... to treat certain infections that are caused by bacteria, including respiratory tract (including pneumonia and bronchitis), urinary ... abdominal (stomach area) infections, that are caused by bacteria. Aztreonam injection also may be used before, during, ...

  1. Ceftazidime Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria including pneumonia and other lower respiratory tract (lung) ... medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as ceftazidime injection will not work ...

  2. Tobramycin Injection

    MedlinePlus

    ... treat certain serious infections that are caused by bacteria such as meningitis (infection of the membranes that ... medications called aminoglycoside antibiotics. It works by killing bacteria.Antibiotics such as tobramycin injection will not work ...

  3. Ciprofloxacin Injection

    MedlinePlus

    ... is used to treat certain infections caused by bacteria such as pneumonia; and infections of the skin, ... of antibiotics called fluoroquinolones. It works by killing bacteria that cause infections.Antibiotics such as ciprofloxacin injection ...

  4. Gentamicin Injection

    MedlinePlus

    ... treat certain serious infections that are caused by bacteria such as meningitis (infection of the membranes that ... medications called aminoglycoside antibiotics. It works by killing bacteria.Antibiotics such as gentamicin injection will not work ...

  5. Ceftaroline Injection

    MedlinePlus

    ... infections and pneumonia (lung infection) caused by certain bacteria. Ceftaroline is in a class of medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as ceftaroline injection will not work ...

  6. Daclizumab Injection

    MedlinePlus

    ... course of disease where symptoms flare up from time to time) of multiple sclerosis (MS; a disease in which ... injections. Before you use daclizumab yourself the first time, read the written instructions that come with it. ...

  7. Risperidone Injection

    MedlinePlus

    ... release (long-acting) injection is used to treat schizophrenia (a mental illness that causes disturbed or unusual ... do not already have diabetes. If you have schizophrenia, you are more likely to develop diabetes than ...

  8. Acyclovir Injection

    MedlinePlus

    ... chickenpox in the past) in people with weak immune systems. It is also used to treat first-time ... from time to time) in people with normal immune systems. Acyclovir injection is used to treat herpes simplex ...

  9. Omalizumab Injection

    MedlinePlus

    ... steroids. Omalizumab is also used to treat chronic hives without a known cause that cannot successfully be ... is not used to treat other forms of hives or allergic conditions. Omalizumab injection is in a ...

  10. Pegloticase Injection

    MedlinePlus

    ... doctor if you have glucose-6-phosphate dehydrogenase (G6PD) deficiency (an inherited blood disease). Your doctor may test you for G6PD deficiency before you start to receive pegloticase injection. If ...

  11. Lacosamide Injection

    MedlinePlus

    ... with other medications to control certain types of seizures in people who cannot take oral medications. Lacosamide ... If you suddenly stop using lacosamide injection, your seizures may happen more often. Your doctor will probably ...

  12. Oxacillin Injection

    MedlinePlus

    ... injection is in a class of medications called penicillins. It works by killing bacteria.Antibiotics such as ... and pharmacist if you are allergic to oxacillin; penicillins; cephalosporin antibiotics such as cefaclor, cefadroxil, cefazolin, cefdinir, ...

  13. Nafcillin Injection

    MedlinePlus

    ... injection is in a class of medications called penicillins. It works by killing bacteria.Antibiotics such as ... and pharmacist if you are allergic to nafcillin; penicillins; cephalosporin antibiotics such as cefaclor, cefadroxil, cefazolin, cefdinir, ...

  14. Ampicillin Injection

    MedlinePlus

    ... injection is in a class of medications called penicillins. It works by killing bacteria.Antibiotics such as ... and pharmacist if you are allergic to ampicillin; penicillins; cephalosporin antibiotics such as cefaclor, cefadroxil, cefazolin (Ancef, ...

  15. Naloxone Injection

    MedlinePlus

    ... emergency medical treatment to reverse the life-threatening effects of a known or suspected opiate (narcotic) overdose. ... is also used after surgery to reverse the effects of opiates given during surgery. Naloxone injection is ...

  16. Omacetaxine Injection

    MedlinePlus

    ... or cannot take these medications due to side effects. Omacetaxine injection is in a class of medications ... a treatment cycle if you experience serious side effects of the medication or if blood tests show ...

  17. Methylnaltrexone Injection

    MedlinePlus

    ... injection is used to treat constipation caused by opioid (narcotic) pain medications in patients with chronic (on-going) pain that is not caused by ... by protecting the bowel from the effects of opioid (narcotic) medications.

  18. Denosumab Injection

    MedlinePlus

    ... menstrual periods), who have an increased risk for fractures (broken bones) or who cannot take or did ... receiving certain treatments that increase their risk for fractures. Denosumab injection (Xgeva) is used to reduce fractures ...

  19. Rasburicase Injection

    MedlinePlus

    ... break down) in people with certain types of cancer who are being treated with chemotherapy medications. Rasburicase injection is in a class of medications called enzymes. It works by breaking down uric acid so that the body can eliminate it.

  20. Gemcitabine Injection

    MedlinePlus

    ... with surgery. Gemcitabine is also used to treat cancer of the pancreas that has spread to other parts of the ... 4 weeks. When gemcitabine is used to treat cancer of pancreas it may be injected once every week. The ...

  1. Doxercalciferol Injection

    MedlinePlus

    Doxercalciferol injection is used to treat secondary hyperparathyroidism (a condition in which the body produces too much parathyroid hormone [PTH; a natural substance needed to control the amount of calcium in ...

  2. Granisetron Injection

    MedlinePlus

    ... that may occur after surgery. Granisetron extended-release (long-acting) injection is used with other medications to prevent nausea and vomiting caused by cancer chemotherapy that may occur immediately ...

  3. Fluconazole Injection

    MedlinePlus

    ... injection is used to treat fungal infections, including yeast infections of the mouth, throat, esophagus (tube leading ... by fungus. Fluconazole is also used to prevent yeast infections in patients who are likely to become ...

  4. Docetaxel Injection

    MedlinePlus

    ... allergic to docetaxel injection or drugs made with polysorbate 80, an ingredient found in some medications. Ask ... if a medication you are allergic to contains polysorbate 80. If you experience any of the following ...

  5. Haloperidol Injection

    MedlinePlus

    ... emotions). Haloperidol injection is also used to control motor tics (uncontrollable need to repeat certain body movements) ... people who have Tourette's disorder (condition characterized by motor or verbal tics). Haloperidol is in a class ...

  6. Injection overview

    SciTech Connect

    Prestwich, S.

    1983-12-01

    The test program was initiated at the Raft River Geothermal Field in southern Idaho in September 1982. A series of eight short-term injection and backflow tests, followed by a long-term injection test, were conducted on one well in the field. Tracers were added during injection and monitored during backflow as well. The principal objective was to determine if tracers could be effectively used as a means to assess reservoir characteristics in a one-well test. The test program resulted in a unique data set which shows promise as a means to improve understanding of the reservoir characteristics. In December 1982, an RFP was issued to obtain an industrial partner to obtain follow-on data on the injection/backflow technique in a second field, and to study any alternate advanced concepts for injection testing which the industrial community might recommend. The East Mesa Geothermal Field was selected for the second test series. Two wells were utilized for testing, and a series of ten tests were conducted in July and August 1983, aimed principally at further evaluation of the injection/backflow technique.

  7. Hydrologic and Geochemical Evaluation of Aquifer Storage Recovery in the Santee Limestone/Black Mingo Aquifer, Charleston, South Carolina, 1998-2002

    USGS Publications Warehouse

    Petkewich, Matthew D.; Parkhurst, David L.; Conlon, Kevin J.; Campbell, Bruce G.; Mirecki, June E.

    2004-01-01

    The hydrologic and geochemical effects of aquifer storage recovery were evaluated to determine the potential for supplying the city of Charleston, South Carolina, with large quantities of potable water during emergencies, such as earthquakes, hurricanes, or hard freezes. An aquifer storage recovery system, including a production well and three observation wells, was installed at a site located on the Charleston peninsula. The focus of this study was the 23.2-meter thick Tertiary-age carbonate and sand aquifer of the Santee Limestone and the Black Mingo Group, the northernmost equivalent of the Floridan aquifer system. Four cycles of injection, storage, and recovery were conducted between October 1999 and February 2002. Each cycle consisted of injecting between 6.90 and 7.19 million liters of water for storage periods of 1, 3, or 6 months. The volume of recovered water that did not exceed the U.S. Environmental Protection Agency secondary standard for chloride (250 milligrams per liter) varied from 1.48 to 2.46 million liters, which is equivalent to 21 and 34 percent of the total volume injected for the individual tests. Aquifer storage recovery testing occurred within two productive zones of the brackish Santee Limestone/Black Mingo aquifer. The individual productive zones were determined to be approximately 2 to 4 meters thick, based on borehole geophysical logs, electromagnetic flow-meter testing, and specific-conductance profiles collected within the observation wells. A transmissivity and storage coefficient of 37 meters squared per day and 3 x 10-5, respectively, were determined for the Santee Limestone/Black Mingo aquifer. Water-quality and sediment samples collected during this investigation documented baseline aquifer and injected water quality, aquifer matrix composition, and changes in injected/aquifer water quality during injection, storage, and recovery. A total of 193 water-quality samples were collected and analyzed for physical properties, major and

  8. Using dye tracing to establish groundwater flow paths in a limestone marble aquifer, University of California, Santa Cruz, California

    SciTech Connect

    Hayes, J.; Bertschinger, V. ); Aley, T. )

    1993-04-01

    Areas underlain by karst aquifers are characterized by soluble rock with sinkholes, caves, and a complex underground drainage network. Groundwater issues such as flow direction, well pumping impacts, spring recharge areas, and potential contamination transport routes are greatly complicated by the unique structure of karst aquifers. Standard aquifer analysis techniques cannot be applied unless the structure of the karst aquifer is understood. Water soluble fluorescent dyes are a powerful tool for mapping the irregular subsurface connections and flow paths in karst aquifers. Mapping the subsurface connections allows reasonable estimates of the hydrologic behavior of the aquifer. Two different fluorescent dyes were injected at two points in a limestone karst aquifer system beneath the University of California, Santa Cruz campus. Flow paths in the marble were thought to be closely tied to easily recognized geomorphic alignments of sinkholes associated with fault and fracture zones. The dye tests revealed unexpected and highly complex interconnections. These complex flow paths only partially corresponded to previous surface mapping and aerial photo analysis of fracture systems. Several interfingering but hydrologically unconnected flow paths evidently exist within the cavernous aquifer. For example, dye did not appear at some discharge springs close to the dye injection points, but did appear at more distant springs. This study shows how a dye tracing study in a small, well-defined limestone body can shed light on a variety of environmental and hydrological issues, including potential well pumping impact areas, wellhead protection and recharge areas, parking lot runoff injection to aquifers, and drainage routes from hazardous materials storage areas.

  9. Analysis of medieval limestone sculpture from southwestern France and the Paris Basin by NAA

    SciTech Connect

    Holmes, L.; Harbottle, G.

    1994-12-31

    Compositional characterization of limestone from sources known to medieval craftsmen and from the monuments they built can be used in conjunction with stylistic and iconographic criteria to infer geographic origin of sculptures that have lost their histories. Limestone from 47 quarrying locations in France and from numerous medieval monuments have been subjected to neutron activation analysis (NAA) to form the nucleus of the Brookhaven Limestone Database. Even though the method and techniques of NAA are well established, this paper briefly summarizes the parameters and experimental conditions useful for determining those concentration variables for which limestone from different sources exhibits significant and reproducible differences.

  10. Limestones of western Newfoundland that magnetized before Devonian folding but after Middle Ordovician lithification

    SciTech Connect

    Hodych, J.P. )

    1989-01-01

    A positive fold test and a negative conglomerate test help determine when and how stable remanence was acquired in the Middle Ordovician Table Head Group limestones of the Port au Port Peninsula of Newfoundland. The limestones magnetized after lithification and incorporation as clasts into a Middle Ordovician breccia. Hence, the limestones do not carry a detrital or other primary remanence despite their very low conodont color alteration index. The remanence may be thermoviscous or diagenetic and was acquired before Devonian folding. This suggests the need for caution in interpreting paleomagnetic results from other early Paleozoic limestones whose remanence resides in magnetite of blocking temperature lower than 400C.

  11. Hydrogeology of the gray limestone aquifer in southern Florida

    USGS Publications Warehouse

    Reese, Ronald S.; Cunningham, Kevin J.

    2000-01-01

    Results from 35 new test coreholes and aquifer-test, water-level, and water-quality data were combined with existing hydrogeologic data to define the extent, thickness, hydraulic properties, and degree of confinement of the gray limestone aquifer in southern Florida. This aquifer, previously known to be present only in southeastern Florida (Miami-Dade, Broward, and Palm Beach Counties) below, and to the west of, the Biscayne aquifer, extends over most of central-south Florida, including eastern and central Collier County and southern Hendry County; it is the same as the lower Tamiami aquifer to the north, and it becomes the water-table aquifer and the upper limestone part of the lower Tamiami aquifer to the west. The aquifer generally is composed of gray, shelly, lightly to moderately cemented limestone with abundant shell fragments or carbonate sand, abundant skeletal moldic porosity, and minor quartz sand. The gray limestone aquifer comprises the Ochopee Limestone of the Tamiami Formation, and, in some areas, the uppermost permeable part of an unnamed formation principally composed of quartz sand. Underlying the unnamed formation is the Peace River Formation of the upper Hawthorn Group, the top of which is the base of the surficial aquifer system. Overlying the aquifer and providing confinement in much of the area is the Pinecrest Sand Member of the Tamiami Formation. The thickness of the aquifer is comparatively uniform, generally ranging from 30 to 100 feet. The unnamed formation part of the aquifer is up to 20 feet thick. The Ochopee Limestone accumulated in a carbonate ramp depositional system and contains a heterozoan carbonate-particle association. The principal rock types of the aquifer are pelecypod lime rudstones and floatstones and permeable quartz sands and sandstones. The pore types are mainly intergrain and separate vug (skeletal-moldic) pore spaces. The rock fabric and associated primary and secondary pore spaces combine to form a dual diffuse

  12. Rare earths in the Leadville Limestone and its marble derivates

    USGS Publications Warehouse

    Jarvis, J.C.; Wildeman, T.R.; Banks, N.G.

    1975-01-01

    Samples of unaltered and metamorphosed Leadville Limestone (Mississippian, Colorado) were analyzed by neutron activation for ten rare-earth elements (REE). The total abundance of the REE in the least-altered limestone is 4-12 ppm, and their distribution patterns are believed to be dominated by the carbonate minerals. The abundances of the REE in the marbles and their sedimentary precursors are comparable, but the distribution patterns are not. Eu is enriched over the other REE in the marbles, and stratigraphically upward in the formation (samples located progressively further from the heat source), the light REE become less enriched relative to the heavy REE. The Eu anomaly is attributed to its ability, unique among the REE, to change from the 3+ to 2+ oxidation state. Whether this results in preferential mobilization of the other REE or whether this reflects the composition of the pore fluid during metamorphism is unknown. Stratigraphically selective depletion of the heavy REE may be attributed to more competition for the REE between fluid and carbonate minerals in the lower strata relative to the upper strata. This competition could have been caused by changes in the temperature of the pore fluid or to the greater resistance to solution of the dolomite in the lower parts of the formation than the calcite in the upper parts. ?? 1975.

  13. Characterizing and modelling 'ghost-rock' weathered limestones

    NASA Astrophysics Data System (ADS)

    Dubois, Caroline; Goderniaux, Pascal; Deceuster, John; Poulain, Angélique; Kaufmann, Olivier

    2016-04-01

    'Ghost-rock' karst aquifer has recently been highlighted. In this particular type of aquifer, the karst is not expressed as open conduits but consists in zones where the limestone is weathered. The in-situ weathering of limestone leaves a soft porous material called 'alterite'. The hydro-mechanical properties of this material differs significantly from those of the host rock: the weathering enhances the storage capacity and the conductivity of the rock. This type of weathered karst aquifer has never been studied from a hydrogeological point of view. In this study, we present the hydraulic characterization of such weathered zones. We also present a modelling approach derived from the common Equivalent Porous Medium (EPM) approach, but including the spatial distribution of hydrogeological properties through the weathered features, from the hard rock to the alterite, according to a weathering index. Unlike the Discrete Fracture Network (DFN) approaches, which enable to take into account a limited number of fractures, this new approach allows creating models including thousands of weathered features. As the properties of the alterite have to be considered at a centimeter scale, it is necessary to upscale these properties to carry out simulations over large areas. Therefore, an upscaling method was developed, taking into account the anisotropy of the weathered features. Synthetic models are built, upscaled and different hydrogeological simulations are run to validate the method. This methodology is finally tested on a real case study: the modelling of the dewatering drainage flow of an exploited quarry in a weathered karst aquifer in Belgium.

  14. Bird species diversity in the padawan limestone area, sarawak.

    PubMed

    Mansor, Mohammad Saiful; Sah, Shahrul Anuar Mohd; Koon, Lim Chan; Rahman, Mustafa Abdul

    2011-12-01

    Bird surveys were conducted in the Padawan Limestone Area for seven days at each of two study sites, Giam and Danu, from August to December 2008. The purpose of the study was to compare the area's bird species richness and abundance of bird species in other limestone areas and in other forest types. The study also compared the species richness and relative abundance of birds in undisturbed and disturbed areas at both study sites. Twenty mist nets were deployed for 12 hours daily. During this study period, direct observations of birds were also made. In all, 80 species from 34 families were recorded at both sites. At Giam, 120 birds were mist-netted. These birds represented 31 species from 16 families. The direct observations at Giam recorded 13 species from 11 families. In the undisturbed area, 21 species from 13 families were mist-netted, whereas in the disturbed area, 21 species from 10 families were mist-netted. In Danu, a total of 48 birds, representing 25 species from 12 families, were mist-netted. The observations at Danu recorded 34 species from 19 families. Twelve species from 7 families were mist-netted in the undisturbed area, whereas 18 species from 11 families were mist-netted in the disturbed area. Statistical analysis showed that the species diversity index differed significantly between undisturbed and disturbed areas.

  15. Bird Species Diversity in the Padawan Limestone Area, Sarawak

    PubMed Central

    Mansor, Mohammad Saiful; Sah, Shahrul Anuar Mohd; Koon, Lim Chan; Rahman, Mustafa Abdul

    2011-01-01

    Bird surveys were conducted in the Padawan Limestone Area for seven days at each of two study sites, Giam and Danu, from August to December 2008. The purpose of the study was to compare the area’s bird species richness and abundance of bird species in other limestone areas and in other forest types. The study also compared the species richness and relative abundance of birds in undisturbed and disturbed areas at both study sites. Twenty mist nets were deployed for 12 hours daily. During this study period, direct observations of birds were also made. In all, 80 species from 34 families were recorded at both sites. At Giam, 120 birds were mist-netted. These birds represented 31 species from 16 families. The direct observations at Giam recorded 13 species from 11 families. In the undisturbed area, 21 species from 13 families were mist-netted, whereas in the disturbed area, 21 species from 10 families were mist-netted. In Danu, a total of 48 birds, representing 25 species from 12 families, were mist-netted. The observations at Danu recorded 34 species from 19 families. Twelve species from 7 families were mist-netted in the undisturbed area, whereas 18 species from 11 families were mist-netted in the disturbed area. Statistical analysis showed that the species diversity index differed significantly between undisturbed and disturbed areas. PMID:24575218

  16. Computerized Shawnee lime/limestone scrubbing model users manual

    SciTech Connect

    Anders, W.L.; Torstrick, R.L.

    1981-03-01

    The manual gives a general description of a computerized model for estimating design and cost of lime or limestone scrubber systems for flue gas desulfurization (FGD). It supplements PB80-123037 by extending the number of scrubber options which can be evaluated. It includes spray tower and venturi/spray-tower absorbers, forced oxidation systems, systems with absorber loop additives (MgO or adipic acid), revised design and economic premises, and other changes reflecting process improvements and variations. It describes all inputs and outputs, along with detailed procedures for using the model and all its options. The model is based on prototype scrubber data from the EPA/Shawnee test facility and should be useful to utility companies, as well as to architectural and engineering contractors who are involved in selecting and designing FGD facilities. As key features, the model provides estimates of capital investment and operating revenue requirements. It also provides a material balance, equipment list, and a breakdown of costs by processing areas. The primary uses of the model are to project comparative economics of lime and limestone FGD processes and to evaluate system alternatives prior to the development of a detailed design.

  17. Limestones distinguished by magnetic hysteresis in three-dimensional projections

    NASA Astrophysics Data System (ADS)

    Borradaile, G. J.; Hamilton, Tom

    2003-09-01

    Magnetic hysteresis data determine the suitability of rocks for paleomagnetic work, provide clues to paleo-environment and paleo-climate and they may characterize depositional environments for limestones. However, the variables chosen for conventional two-dimensional hysteresis plots, such as that of Day et al. [1977], are not always suitable to discriminate between samples. Distinguishing samples by their regression surfaces in 3D hysteresis space may be more successful in some cases [Borradaile and Lagroix, 2000] but a 2D projection with a less arbitrary viewing axis is preferable for routine reporting. We show that limestone samples are simply discriminated in a new 2D projection produced by projecting hysteresis data from three dimensions (x, y, z = Mr/Ms, Bcr, Bc) onto a plane containing the Mr/Ms axis. The orientation of the plane is controlled by its x-axis that is defined by a suitably selected Bcr/Bc ratio, most often in the magnetite PSD range, 2< (Bcr/Bc) < 4.

  18. Colmenar limestone as a resource for built heritage

    NASA Astrophysics Data System (ADS)

    Fort, Rafael; Álvarez de Buergo, Mónica; Varas-Muriel, MªJosé; Mercedes Pérez-Monserrat, Elena

    2013-04-01

    The Colmenar stone (or Colmenar limestone) has been used in the construction of significant builidings of the Central area of Spain, such as the Royal Palace of Aranjuez (16th -18th centuries) or the Royal Palace of Madrid (18th century). Nowadays this building stone is still widely used, both for new construction and restoration works, as well as for the indoor ornamentation of emblematic buildings such as the Royal Theater of Madrid (20th century). There are many quarries from where this stone was exploited, being the most prestigious ones those located in Colmenar de Oreja, at 50 km Southeast the city of Madrid. The high quality of the stone in these quarries, its whiteness and pureness, made this locality the most relevant in these stonés extractive activities, concentrating the most relevant exploitations and providing the stone the denomination of the municipality (Colmenar). It was an underground mining extraction until the 20th century in order to reach the highest quality level of the mine, the so called "Banco Gordo" (Thick Bank). Generically known as moorland limestone, this rock belongs to the fluvial-lacustrine carbonates of the Upper Miocene Unit of the Tertiary Madrid's Basin. Its tonality mainly ranges from white to cream and even light grey. Under a petrographic point of view, this limestone is constituted by 40% of bioclasts (characea, ostracods and gasteropods), 20-30% of micritic matrix and 30-40% of sparitic cement. Therefore, it can be classified as a biomicrite/biosparite limestone or as a bioclastic packstone. Some particularities of these limestones regarding their appearance are related to some karstic processes they underwent linked to some dissolution phenomena during the Pliocene. All of this resulted on an abundance of cavities with terra rossa fillings, a non-soluble clayey residue, iron enriched, which is the responsible for the reddish and pinkish color that the Colmenar stone sometimes shows. These petrographic characteristics

  19. Regional stratigraphy of Smackover limestone (Jurassic) in south Arkansas and north Louisiana, and geology of Chalybeat Springs oil field

    SciTech Connect

    Troell, A.R.; Robinson, J.D.

    1987-09-01

    Prior to 1960, the Reynolds oolite of the Smackover Formation of south Arkansas, was correlated with the Smackover B oolite of north Louisiana. The absence of anticlines with structural closure and the paucity of untested fault closures along the Arkansas-Louisiana boundary provided little exploratory interest in the area. Discovery of oil at Lick Creek field in 1960 and at Walker Creek in 1968 revealed a trend of traps and led to the geologic investigation that resulted in the discovery, in 1972, of Chalybeat Springs field, in Columbia County, Arkansas. Chalybeat Springs field is a combination stratigraphic-structural trap in oolitic calcarenite at a depth of 10,250 ft in the Smackover B limestone. Production is limited by the combination of a tilted anticline with porosity pinch-out on its flank. The field originally had 28 producing wells and 10 dry holes, and covered approximately 4500 productive acres. Original oil in place is estimated to have been 37 million bbl and cumulative production through 1985 was approximately 12 million bbl. The geologic relationships and principles observed in the Smackover Limestone of south Arkansas and north Louisiana have been successfully applied to other regions and in carbonate strata of different age, in the search for oil and gas production. Practical geologic studies of carbonate rocks, aided by examination of drill cuttings, cores, and thin sections, combined with mechanical log evaluation, result in lower finding costs for oil and gas reserves.

  20. Study on the influence of the decoking agent on the activity of limestone in wet flue gas desulfurization

    NASA Astrophysics Data System (ADS)

    Li, Qianjun; Xu, Dongyang; Wu, Yunxia; Yu, Jin

    2017-01-01

    Influence of the main components of decoking agent (magnesium nitrate, aluminum nitrate, copper nitrate, ammonium nitrate and actual decoking agent) on the activity of limestone is studied in laboratory by MET method. Results show that magnesium nitrate, ammonium nitrate and copper nitrate almost has no effect on the activity of limestone. With the concentration increasing, aluminum nitrate has an increasing inhibition on the dissolution of limestone. Fly ash has inhibition on dissolution of limestone due to the blockage of limestone pore by fly ash. The actual decoking agent has almost no effect on the limestone.

  1. Pentostatin Injection

    MedlinePlus

    ... pain constipation sores in the mouth and throat flatulence or large amounts of gas in the intestines or bowels hair loss muscle, back, or joint pain headache sweating difficulty falling asleep or staying asleep dry skin itching loss of strength or energy Some side effects can be serious. If you ...

  2. Crystallographic transformation of limestone during calcination under CO2.

    PubMed

    Valverde, Jose Manuel; Medina, Santiago

    2015-09-14

    The calcination reaction of limestone (CaCO3) to yield lime (CaO) is at the heart of many industrial applications as well as natural processes. In the recently emerged calcium-looping technology, CO2 capture is accomplished by the carbonation of CaO in a gas-solid reactor (carbonator). CaO is derived by the calcination of limestone in a calciner reactor under necessarily high CO2 partial pressure and high temperature. In situ X-ray diffraction (XRD) has been employed in this work to gain further insight into the crystallographic transformation that takes place during the calcination of limestone under CO2, at partial pressures (P) close to the equilibrium pressure (Peq) and at high temperature. Calcination under these conditions becomes extremely slow. The in situ XRD analysis presented here suggests the presence of an intermediate metastable CaO* phase stemming from the parent CaCO3 structure. According to the reaction mechanism proposed elsewhere, the exothermicity of the CaO* → CaO transformation and high values of P/Peq inhibit the nucleation of CaO at high temperatures. The wt% of CaO* remains at a relatively high level during slow calcination. Two diverse stages have been identified in the evolution of CaO crystallite size, L. Initially, L increases with CaCO3 conversion, following a logarithmic law. Slow calcination allows the crystallite size to grow up from a few nanometers at nucleation up to around 100 nm near the end of conversion. Otherwise, quick calcination at relatively lower CO2 concentrations limits CaO crystallite growth. Once calcination reaches an advanced state, the presence of CaO* drops to zero and the rate of increase of the CaO crystallite size is significantly hindered. Arguably, the first stage in CaO crystallite growth is driven by aggregation of the metastable CaO* nanocrystals, due to surface attractive forces, whereas the second one is consistent with sintering of the aggregated CaO crystals, and persists with time after full

  3. Limestone-particle-stabilized macroemulsion of liquid and supercritical carbon dioxide in water for ocean sequestration.

    PubMed

    Golomb, D; Barry, E; Ryan, D; Lawton, C; Swett, P

    2004-08-15

    When liquid or supercritical CO2 is mixed with an aqueous slurry of finely pulverized (1-20 microm) limestone (CaCO3) in a high-pressure reactor, a macroemulsion is formed consisting of droplets of CO2 coated with a sheath of CaCO3 particles dispersed in water. The coated droplets are called globules. Depending on the globule diameter and the CaCO3 sheath thickness, the globules sink to the bottom of the water column, are neutrally buoyant, or float on top of the water. The CaCO3 particles are lodged at the CO2/ H2O interface, preventing the coalescence of the CO2 droplets, and thus stabilizing the CO2-in-water emulsion. We describe the expected behavior of a CO2/H2O/CaCO3 emulsion plume released in the deep ocean for sequestration of CO2 in the ocean to ameliorate global warming. Depending on the amount of CO2 injected, the dense plume will descend a few hundred meters while entraining ambient seawater until it acquires neutral buoyancy in the stratified ocean. After equilibration, the globules will rain out from the plume toward the ocean bottom. This mode of CO2 release will prevent acidification of the seawater around the release point, which is a major environmental drawback of ocean sequestration of liquid, unemulsified CO2.

  4. Pegaptanib Injection

    MedlinePlus

    ... if you have or have ever had diabetes, high blood pressure, a heart attack, or a stroke.tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while using pegaptanib injection, ...

  5. Ramucirumab Injection

    MedlinePlus

    ... doctor if you have or have ever had high blood pressure, a wound that has not healed, or liver disease.tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding. Ramucirumab injection may harm your unborn baby. You ...

  6. Reslizumab Injection

    MedlinePlus

    ... the infusion or for a short period of time after the infusion has finished.You will receive each injection of reslizumab in a doctor's office or medical facility. You will stay in the office for some time after you receive the medication so your doctor ...

  7. Dexrazoxane Injection

    MedlinePlus

    ... are used to treat or prevent certain side effects that may be caused by chemotherapy medications. Dexrazoxane ... Dexrazoxane injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away: pain or swelling in the place ...

  8. Identification of Calcium Sulphoaluminate Formation between Alunite and Limestone

    PubMed Central

    Kim, Hyung-Seok; Han, Gi-Chun; Ahn, Ji-Whan; Cho, Kye-Hong; Cho, Hee-Chan

    2009-01-01

    This study was carried out to identify the conditions of formation of calcium sulphoaluminate (3CaO·3Al2O3·CaSO4) by the sintering of a limestone (CaCO3) and alunite [K2SO4·Al2(SO4)3·4Al(OH)3] mixture with the following reagents: K2SO4, CaCO3, Al(OH)3, CaSO4·2H2O, and SiO2. When K2SO4, CaCO3, Al(OH)3, CaSO4·2H2O were mixed in molar ratios of 1:3:6:3 and sintered at 1,200∼1,300 °C, only 3CaO·3Al2O3·CaSO4 and calcium langbeinite (2CaSO4·K2SO4) were generated. With an amount of CaO that is less than the stoichiometric molar ratio, 3CaO·3Al2O3·CaSO4 was formed and anhydrite (CaSO4) did not react and remained behind. With the amount of CaSO4 that is less than the stoichiometric molar ratio, the amounts of 3CaO·3Al2O3·CaSO4 and 2CaSO4·K2SO4 decreased, and that of CaO·Al2O3 increased. In the K2SO4-CaO-Al2O3-CaSO4-SiO2 system, to stabilize the formation of 3CaO·3Al2O3·CaSO4, 2CaSO4·K2SO4, and β-2CaO·SiO2, the molar ratios of CaO: Al2O3: CaSO4 must be kept at 3:3:1 and that of CaO/SiO2, over 2.0; otherwise, the generated amount of 3CaO·3Al2O3·CaSO4 decreased and that of gehlenite (2CaO·Al2O3·SiO2) with no hydration increased quantitatively. Therefore, if all SO3(g) generated by the thermal decomposition of alunite reacts with CaCO3 (or CaO, the thermal decomposition product of limestone) to form CaSO4 in an alunite- limestone system, 1 mol of pure alunite reacts with 6 mol of limestone to form 1 mol of 3CaO·3Al2O3·CaSO4 and 1 mol of 2CaSO4·K2SO4. PMID:22346687

  9. Producing Portland cement from iron and steel slags and limestone

    SciTech Connect

    Monshi, A.; Asgarani, M.K.

    1999-09-01

    The slags from blast furnace (iron making) and converter (steel making) after magnetic separation are mixed with limestone of six different compositions. The ground materials are fired in a pilot plant scale rotary kiln to 1,350 C for 1 h. The clinker is cooled, crushed, mixed with 3% gypsum, and ground to fineness of more than 3,300 cm{sub 2}/g. Initial and final setting times, consistency of standard paste, soundness, free CaO, and compressive and fractural strengths after 3, 7, and 28 days are measured. Samples with higher lime saturation factor developed higher C{sub 3}S content and better mechanical properties. Blending 10% extra iron slag to a cement composed of 49% iron slag, 43% calcined lime, and 8% steel slag kept the compressive strength of concrete above standard values for type I ordinary Portland cement.

  10. OPTIMIZATION OF A PULSED LIMESTONE BED REACTOR AT THE ARGO TUNNEL IN IDAHO SPRINGS, COLORADO

    EPA Science Inventory

    Acid Mine Drainage (AMD) is an unintended consequence of coal and metal mining that adversely affects thousands of miles of streams both in the eastern and western regions of the U.S. A novel AMD treatment process based on limestone based on limestone neutralization has been dev...

  11. Adsorption and desorption of phosphate on limestone in experiments simulating seawater intrusion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The absorption and desorption of phosphorus on a large block of limestone was investigated using deionized water (DIW) and seawater. The limestone had a high affinity to adsorb phosphorus in DIW. Phosphate adsorption was significantly less in seawater, and more phosphorus was desorbed in the seawate...

  12. 76 FR 35396 - Black Hills National Forest, Mystic Ranger District, South Dakota, Section 30 Limestone Mining...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-17

    ... Mining Project AGENCY: Forest Service, USDA. ACTION: Corrected Notice of intent to prepare an... the purpose of mining for chemical grade limestone within mining claims on National Forest System land... publication dates. A Notice of Availability for the Section 30 Limestone Mining Project Draft EIS...

  13. STEAM ENHANCED REMEDIATION RESEARCH FOR DNAPL IN FRACTURED ROCK, LORING AIR FORCE BASE, LIMESTONE, MAINE

    EPA Science Inventory

    This report details a research project on Steam Enhanced Remediation (SER) for the recovery of volatile organic compounds from fractured limestone that was carried out at the Quarry at the former Loring Air Force Base in Limestone, Maine. This project was carried out by USEPA, Ma...

  14. Thermal strengthening of limestone: monument preservation during fire

    NASA Astrophysics Data System (ADS)

    Heap, Michael; Lavallee, Yan; Benson, Philip; Hess, Kai-Uwe; Dingwell, Donald

    2010-05-01

    The use of natural rocks in the construction of buildings and monuments predates the use of commercially engineered materials such as concrete. Such building material can be subject to elevated temperatures in the misfortunate event of a fire. In civil engineering, it is generally appreciated that the strength of rock is decreased when it is or has been exposed to elevated temperatures. This is due the formation of thermal microcracks, a result of the thermal expansion mismatch between different minerals in the rock. Even today, fire is by no means an uncommon occurrence and approximately one historic building is lost to fire in the European Union every day (COST C17 2001). A large number of historically significant buildings and monuments are constructed from carbonate material. However, could the paradigm of thermal weakening of limestone construction material be in part, a paradox? We report new findings on the thermal strengthening of the Solnhofen limestone (Solnhofen, Germany), a carbonate rock traditionally used in construction of building and statues in central Europe. Two types of deformation experiments were performed to investigate: (1) the strength of samples at elevated temperatures (i.e. during fire) and (2) the strength of samples at room temperature after heat-treatment (i.e. after fire). During experimentation, microcracking was monitored by the output of acoustic emissions (AE). Thermo-gravimetric (TG) analysis was also undertaken to measure the mass loss during heating. For the experiments ‘during fire', samples were heated to temperatures of 25°, 200°, 400°, 500°, 600°, 650° and 800°C at a controlled rate of 5°C/min and deformed until failure in a uniaxial press at a constant strain rate of 10-5 s-1. For the experiments ‘after fire', samples were heat-treated to each 100°C increment up to 800°C, they were then cooled at the same rate and their strength tested at room temperature. The mechanical data demonstrate that, during fire

  15. Toxicity of acid mine pit lake water remediated with limestone and phosphorus.

    PubMed

    Neil, Luke L; McCullough, Clint D; Lund, Mark A; Evans, Louis H; Tsvetnenko, Yuri

    2009-11-01

    Pit lakes are increasingly common worldwide and have potential to provide many benefits. However, lake water toxicity may require remediation before beneficial end uses can be realised. Three treatments to remediate AMD (pH approximately 4.8) pit lake water containing elevated concentrations of Al and Zn from Collie, Western Australia were tested in mesocosms. Treatments were: (a) limestone neutralisation (L), (b) phosphorus amendment (P), and (c) combined limestone neutralisation and phosphorus amendment (L+P). Laboratory bioassays with Ceriodaphnia cf. dubia, Chlorella protothecoides and Tetrahymena thermophila assessed remediation. Limestone neutralisation increased pH and reduced heavy metal concentrations by 98% (Al) to 14% (Mg), removing toxicity to the three test species within 2 months. Phosphorus amendment removed toxicity after 6 months of treatment. However, phosphorus amendment to prior limestone neutralisation failed to reduce toxicity more than limestone neutralisation alone. Low concentrations of both phosphorus and nitrogen appear to limit phytoplankton population growth in all treatments.

  16. Toxicity of acid mine pit lake water remediated with limestone and phosphorus

    SciTech Connect

    Neil, L.L.; McCullough, C.D.; Lund, M.A.; Evans, L.H.; Tsvetnenko, Y.

    2009-11-15

    Pit lakes are increasingly common worldwide and have potential to provide many benefits. However, lake water toxicity may require remediation before beneficial end uses can be realised. Three treatments to remediate AMD (pH similar to 4.8) pit lake water containing elevated concentrations of Al and Zn from Collie, Western Australia were tested in mesocosms. Treatments were: (a) limestone neutralisation (L), (b) phosphorus amendment (P), and c) combined limestone neutralisation and phosphorus amendment (L+P). Laboratory bioassays with Ceriodaphnia cf. dubia, Chlorella protothecoides and Tetrahymena thermophila assessed remediation. Limestone neutralisation increased pH and reduced heavy metal concentrations by 98% (Al) to 14% (Mg), removing toxicity to the three test species within 2 months. Phosphorus amendment removed toxicity after 6 months of treatment. However, phosphorus amendment to prior limestone neutralisation failed to reduce toxicity more than limestone neutralisation alone. Low concentrations of both phosphorus and nitrogen appear to limit phytoplankton population growth in all treatments.

  17. Dissolution rate of limestone for wet flue gas desulfurization in the presence of sulfite.

    PubMed

    Xiang, Gao; Rui-tang, Guo; Hong-lei, Ding; Zhong-yang, Luo; Ke-fa, Cen

    2009-09-15

    Limestone dissolution rate was measured by a pH-stat method with CO(2) sparging and dissolved sulfite. The dissolution rate of limestone under these conditions was found to be controlled by mass transfer and surface kinetics. As can be seen from the results, in the presence of sulfite, limestone dissolution rate increases with increasing stirring speed, reaction temperature and CO(2) partial pressure. The crystallinity of limestone has a great impact on the dissolution rate: The lower the value of the crystallinity of limestone is, the higher the dissolution rate is. The presence of sulfite promotes the dissolution rate when pH value is below 5.5 but inhibits it when pH value is above 5.5.

  18. FMC limestone double-alkali flue gas desulfurization process: Pilot plant testing: Final report

    SciTech Connect

    Troupe, J.S.; Shepley, D.C.

    1987-07-01

    This report documents pilot plant testing of a 3 MW (9500 acfm equivalent flue gas flow) FMC limestone double alkali FGD process operating on a slipstream of a commercial 420 MW boiler burning 3.5% sulfur coal. The report discusses the rationale behind EPRI's decision to participate in the testing aspects of this project, the history of the development of limestone double alkali technology, and the chemistry involved in this technology's operation. The largest part of the report is devoted to the results obtained from tests conducted during 65 days of pilot plant operation. All of the major raw and reduced operating and analytical data taken during testing are reproduced in the appendices to the report, along with quality assurance information to support the validity of the data obtained. The report discusses the test results in detail and presents technical observations regarding their implications. The FMC limestone double alkali FGD process (1) can consistently remove 92 to 93% of SO/sub 2/ from high-sulfur coal flue gas, (2) can achieve high limestone utilization and low soda ash losses, (3) produces a manageable waste filter cake, (4) is highly tolerant of upsets in limestone feed, soda ash makeup, and regeneration residence time, and (5) presents no unusual safety or environmental problems. The process, like conventional limestone scrubbing, shows some adverse effects of increasing soluble magnesium concentration on solids quality and requires a finely ground limestone feed material to achieve high limestone utilization. However, neither limestone grind nor magnesium concentration appears to affect SO/sub 2/ removal efficiency. The report suggests specific lines of future developmental work and future demonstration testing to enhance the attractiveness of this process to the electric utility industry. A bibliography of limestone double alkali literature is included. 3 refs., 25 figs., 4 tabs.

  19. DEMONSTRATION OF SORBENT INJECTION TECHNOLOGY ON A WALL-FIRED UTILITY BOILER (EDGEWATER LIMB DEMONSTRATION)

    EPA Science Inventory

    The report gives results of the full-scale demonstration of Limestone Injection Multistage Burner (LIMB) technology on the coal-fired, 105 MW, Unit 4 boiler at Ohio Edison's Edgewater Station. eveloped as a technology aimed at moderate levels of sulfur dioxide (SO2) and nitrogen ...

  20. DEMONSTRATION OF SORBENT INJECTION TECHNOLOGY ON A TANGENTIALLY COAL-FIRED UTILITY BOILER (YORKTOWN LIMB DEMONSTRATION)

    EPA Science Inventory

    The report summarizes activities conducted and results achieved in an EPA-sponsored program to demonstrate Limestone Injection Multistage Burner (LIMB) technology on a tangentially fired coal-burning utility boiler, Virginia Power's 180-MWe Yorktown Unit No. 2. his successfully d...

  1. The effect of treatment with a 1% injectable formulation of moxidectin during the rainy season and at the beginning of the dry season on gastrointestinal nematodes in cattle from communal areas in Zimbabwe.

    PubMed

    Moyo, D Z; Hendrikx, W M L; Obwolo, M J; Eysker, M

    2003-02-01

    The effect of 1% moxidectin/cydectin at 0.2 mg/kg live weight on gastrointestinal nematodes and on the growth of calves, weaners and cows was investigated in five communal areas on the highveld of Zimbabwe. Three field experiments were carried out between March 1996 and June 1997. In experiment 1, treatment was administered in all five areas at the end of the rainy season in March 1996, followed by a further treatment at the beginning of the dry season in May/June 1996. In experiment 2, the treatment was administered in three areas at the end of the rainy season in March 1997. In experiment 3, treatment was administcred in one area at the beginning of the dry season in April 1997. Large numbers of eggs were present in the faeces of calves and weaners at the start of experiments 1 and 2. Epg values were lower in cows and in all age categories in experiment 3. There was a statistically significant reduction in epg values in calves, weaners and cows following treatment with a reduction of 90-99% in all cases except in cows in experiment 3, where no meaningful assessment was possible owing to the low egg counts in both the treated and control cows. The dominating larval types in faecal cultures were Cooperia and Haemonchus. Trichostrongylus, Oesophagostomum and Bunostomum were also found. Following treatment, Haemonchus was suppressed far more than Cooperia. This may be related to a longer residual effect against abomasal parasites like Haemonchus in comparison to small intestinal worms like Cooperia. Anthelmintic treatment conferred significant weight gain advantages (p < 0.05) on treated calves. weaners and cows. The weight gains are discussed in relation to disease and nutrition.

  2. Dolomitization and over-dolomitization in the Vajont limestone (Dolomiti Bellunesi, Italy) controlled by Mesozoic normal faults: a microstructural and diagenesis study

    NASA Astrophysics Data System (ADS)

    Cortinovis, Silvia; Swennen, Rudy; Bistacchi, Andrea

    2015-04-01

    The Vajont Gorge (Dolomiti Bellunesi, Italy) provides spectacular outcrops of Jurassic limestones (Vajont Limestone Formation) in which Mesozoic faults and fracture corridors are continuously exposed. Some of these faults acted as conduits for Mg-enriched hydrothermal fluids resulting in structurally-controlled dolomitization of the limestone. The dolomitization resulted in several dolomite bodies (100-200 m thick and several hundreds of meters along fault strike) that are particularly interesting as reservoir analogues for hydrocarbon, CO2, or water-bearing systems. The dolomitization process occurred after deposition and compaction of the oolitic limestone (dolomitization post-dates a dissolution event that affected the internal parts of the oolites), but before the Alpine contractional deformation. In fact, the meso-structural data collected in the Vajont Gorge allowed the reconstruction of a 3D model showing that the circulation of the dolomitizing fluids into the limestone host rock, but also the late stage of porosity reduction (strong pore filling due to over-dolomitization) were controlled by normal faults and fracture corridors interpreted as Pre-Alpine (Jurassic or Cretaceous). Later on, the influence of Alpine (Tertiary) deformation have been very limited in the studied volume. For instance dolomite veins are sometimes overprinted by bed-inclined stylolites consistent with Alpine shortening axes, but no large Alpine fault is present in the studied outcrops. Cathodoluminescence microscopy allowed recognizing different growth stages saddle dolomite crystals, which point to varying precipitation conditions during three main stages of dolomitization. Dolomite and calcite crystal twinning suggests deformation under increasing temperature conditions, consistent with intracrystalline plasticity deformation mechanisms. The presence of cataclasites composed of hydrothermal dolostone clasts, in turn cemented by dolomite, or of dolomite veins and compaction

  3. Pathogen and chemical transport in the karst limestone of the Biscayne aquifer: 3. Use of microspheres to estimate the transport potential of Cryptosporidium parvum oocysts

    USGS Publications Warehouse

    Harvey, R.W.; Metge, D.W.; Shapiro, A.M.; Renken, R.A.; Osborn, C.L.; Ryan, J.N.; Cunningham, K.J.; Landkamer, L.

    2008-01-01

    The vulnerability of a municipal well in the Northwest well field in southeastern Florida to potential contamination by Cryptosporidium parvum oocysts was assessed in a large-scale, forced-gradient (convergent) injection and recovery test. The field study involved a simultaneous pulse introduction of a nonreactive tracer (SF6, an inert gas) and oocyst-sized (1.6, 2.9, and 4.9 ??m diameter) carboxylated polystyrene microspheres into karst limestone of the Biscayne aquifer characterized by a complex triple (matrix, touching-vug, and conduit) porosity. Fractional recoveries 97 m down gradient were inversely related to diameter and ranged from 2.9% for the 4.9 ??m microspheres to 5.8% for 1.6 ??m microspheres. Their centers of mass arrived at the pumping well approximately threefold earlier than that of the nonreactive tracer SF6 (gas), underscoring the need for use of colloid tracers and field-scale tracer tests for these kinds of evaluations. In a modified triaxial cell using near in situ chemical conditions, 2.9 and 4.9 ??m microspheres underestimated by fourfold to sixfold the attachment potential of the less electronegative 2.9-4.1 ??m oocysts in the matrix porosity of limestone core samples. The field and laboratory results collectively suggested that it may take 200-300 m of transport to ensure even a 1-log unit removal of oocysts, even though the limestone surfaces exhibited a substantive capability for their sorptive removal. The study further demonstrated the utility of microspheres as oocyst surrogates in field-scale assessments of well vulnerability in limestone, provided that differences in attachment behaviors between oocysts and microspheres are taken into account. Copyright 2008 by the American Geophysical Union.

  4. Landing and Oviposition Responses of Rhagoletis indifferens (Dipt., Tephritidae) on Sweet Cherry Treated with Kaolin- and Limestone-Based Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Kaolin- and limestone-based products were compared for their effects on landing and oviposition on sweet cherry by Rhagoletis indifferens Curran (Dipt., Tephritidae). Surround (95% calcined kaolin), Cocoon (100% hydrous kaolin), Eclipse (>97% limestone), and Purshade (62.5% limestone) were studied....

  5. Stratigraphy and sedimentology of the Upper Cretaceous (Campanian) Anacacho Limestone, Texas, USA

    USGS Publications Warehouse

    Swezey, C.S.; Sullivan, E.C.

    2004-01-01

    The Upper Cretaceous Anacacho Limestone is exposed in outcrops between the cities of San Antonio and Del Rio, Texas. A detailed study of four outcrops (Blanco Creek section, Sabinal River section, Seco Creek section, Hondo Creek section) shows that the Anacacho Limestone rests on the Upson Clay (which contains fauna of early Campanian age) and is overlain by the Corsicana Marl (which contains fauna of early Maastrichtian age). An unconformity within the Anacacho Limestone is used herein to separate the limestone into a lower member and an upper member. The lower Anacacho member contains fauna of early Campanian age, whereas the upper Anacacho member contains fauna of middle Campanian age. The lower Anacacho member consists predominantly of wackestones to packstones, which are overlain by packstones to grainstones capped by the unconformity. This unconformity is interpreted as a marine flooding surface, delineating a transition from carbonate grainstones deposited in shallow water (<30 m depth) to a chalk deposited in deeper water. Above the unconformity, the upper Anacacho member is characterized by a chalk, overlain by wackestones and packstones. The uppermost section of the Anacacho Limestone consists of packstones and grainstones with abundant and diverse fossils. Most of the Anacacho Limestone developed in relatively shallow water (<50 m depth) leeward of a large carbonate build-up (possibly a rudistid reef) that now comprises the Anacacho Mountains. The environment, however, was open to marine water throughout deposition of the Anacacho Limestone. ?? 2004 Elsevier Ltd. All rights reserved.

  6. Preliminary microfacies analysis and cyclicity of the Wahoo Limestone, Lisburne Field, North Slope, Alaska

    SciTech Connect

    Morgan, S.K.; Watts, K.F.

    1995-05-01

    A well from the Lisburne field near Prudhoe Bay was examined in core, thin section, and on well logs for comparison with Wahoo Limestone in the Arctic National Wildlife Refuge (ANWR). Carbonate cycles (parasequences) are well developed in both areas but the greater abundance of terrigenous sediment and associated carbonate facies indicate that the study well is located in a more landward position on the Wahoo carbonate ramp, closer to a source of terrigenous sediment. This report presents the preliminary results of microfacies analyses that have been conducted on 424 of a total 1,115 thin sections from the study well. The stratigraphic nomenclature extended from ANWR (the type locality of the Wahoo Limestone) is different that the terminology previously used for the subsurface Lisburne Group near Prudhoe Bay. We distinguish informal lower and upper members within the Mississippian to Pennsylvanian Wahoo Limestone which overlies the Mississippian Alapah Limestone. Our upper Alapah corresponds to the middle Alapah of previous workers. Our lower Wahoo Limestone member corresponds to the upper Alapah of previous workers. Our upper Wahoo Limestone member corresponds to the previous Wahoo Limestone and is the major hydrocarbon reservoir at the Lisburne field, which is characterized by well-developed carbonate cycles (parasequences).

  7. ARD remediation with limestone in a CO2 pressurized reactor

    USGS Publications Warehouse

    Sibrell, Philip L.; Watten, Barnaby J.; Friedrich, Andrew E.; Vinci, Brian J.

    2000-01-01

    We evaluated a new process for remediation of acid rock drainage (ARD). The process treats ARD with intermittently fluidized beds of granular limestone maintained within a continuous flow reactor pressurized with CO2. Tests were performed over a thirty day period at the Toby Creek mine drainage treatment plant, Elk County, Pennsylvania in cooperation with the Pennsylvania Department of Environmental Protection. Equipment performance was established at operating pressures of 0, 34, 82, and 117 kPa using an ARD flow of 227 L/min. The ARD had the following characteristics: pH, 3.1; temperature, 10 °C; dissolved oxygen, 6.4 mg/L; acidity, 260 mg/L; total iron, 21 mg/L; aluminum, 22 mg/L; manganese, 7.5 mg/L; and conductivity, 1400 μS/cm. In all cases tested, processed ARD was net alkaline with mean pH and alkalinities of 6.7 and 59 mg/L at a CO2 pressure of 0 kPa, 6.6 and 158 mg/L at 34 kPa, 7.4 and 240 mg/L at 82 kPa, and 7.4 and 290 mg/L at 117 kPa. Processed ARD alkalinities were correlated to the settled bed depth (p<0.001) and CO2 pressure (p<0.001). Iron, aluminum, and manganese removal efficiencies of 96%, 99%, and 5%, respectively, were achieved with filtration following treatment. No indications of metal hydroxide precipitation or armoring of the limestone were observed. The surplus alkalinity established at 82 kPa was successful in treating an equivalent of 1136 L/min (five-fold dilution) of the combined three ARD streams entering the Toby Creek Plant. This side-stream capability provides savings in treatment unit scale as well as flexibility in treatment effect. The capability of the system to handle higher influent acidity was tested by elevating the acidity to 5000 mg/L with sulfuric acid. Net alkaline effluent was produced, indicating applicability of the process to highly acidic ARD.

  8. Rehabilitation of lands mined for limestone in the Indian desert

    USGS Publications Warehouse

    Sharma, K.D.; Kumar, S.; Gough, L.P.

    2000-01-01

    In the Indian desert, the economics of mining is second only to agriculture in importance. However, research on the rehabilitation of land disturbed by mining has only recently received serious attention. An attempt has been made to determine both the qualitative and quantitative success of rehabilitation plans used to revegetate limestone mine spoils in an area near Barna, northwest arid India. Rehabilitation success was achieved using a combination of rainwater harvesting techniques, soil amendment application approaches, plant establishment methods and the selection of appropriate germplasm material (trees, shrubs and grasses). It is expected that the resulting vegetative cover will be capable of self-perpetuation under natural conditions while at the same time meeting the land-use needs of the local people. The minespoils have adequate levels of the major nutrients (except P, Mo and Se) for proper plant and grazing animal health. Levels of organic matter are low whereas total B concentrations are exceptionally high. Also, the population of soil fungi, Azotobactor, and nitrifying bacteria is negligible. Enhanced plant growth was achieved in treated plots, compared to control plots, where spoil moisture storage was improved by 5-45 per cent. Due to the decomposition of farmyard manure and nitrogen fixation by planted leguminous plant species, the electrical conductance of treated mine spoils increased threefold, CaCO3 content decreased from 20??0 to 5??2 per cent, and organic carbon, P, K, and biological activity increased significantly. The rehabilitation protocol used at the site appears to have been successful because plant self-regeneration is occurring. The increased diversity of woody perennials resulted in 'dominance' being better shared among species and 'evenness' being increased within the plant community elements. The early to mid-successional trends are continuing for six years following initial rehabilitation. This study developed methods for the

  9. Desulfurization with a modified limestone formulation in an industrial CFBC boiler

    SciTech Connect

    Young Goo Park; Seung Ho Kim

    2006-02-01

    This work presents a practical result of experimental investigation of the limestone particle size effect on de-SOx from a circulating fluidized bed combustion (CFBC) boiler that burns domestic anthracite and is the first industrial scale in Korea. Because of combustion problems such as clinker formation, fine limestone has not been used as a desulfurization agent. The present test, however, showed that higher content (up to 50%) of the particles under 0.1 mm did not entail any malfunction in a modern CFBC system. In addition, the desulfurization efficiency was found to be comparable to the old mode of limestone sorbents. 17 refs., 4 figs., 3 tabs.

  10. Effects of particle size distribution on limestone dissolution in wet FGD process applications

    SciTech Connect

    Ukawa, Naohiko; Takashina, Toru; Shinoda, Naoharu ); Shimizu, Taku )

    1993-08-01

    The kinetics of limestone dissolution in the wet type flue gas desulfurization (FGD) processes has been studied. The rates of dissolution and particle size reduction were measured in both batch and continuous reaction systems for limestone of different size distributions. A predictive model was developed based on mass transfer mechanisms. It was in good agreement with experimental data. Moreover, the rate of dissolution for 25 limestones of different compositions and size distributions were measured in apparatus with a sulfur dioxide absorber which simulated FGD processes. The model was also in good agreement with these results. 11 refs., 8 figs., 2 tabs.

  11. Meteoric stabilization and preservation of limestone within late Proterozoic Beck Spring Dolomite of eastern California

    SciTech Connect

    Zempolich, W.G.; Wilkinson, B.H.; Lohmann, K.C.

    1989-04-01

    Petrographic and geochemical study of limestone, silicified carbonate, and dolostone indicates that meteoric diagenetic processes and paleogeographic position played important roles in the stabilization and preservation of limestone within the pervasively dolomitized Beck Spring Dolomite. The authors conclude that Beck Spring marine cement allochems precipitated as aragonite and high-magnesium calcite. In the vicinity of Saratoga Spring, these metastable mineralogies were dissolved, eroded, stabilized to calcite, and replaced by silica through interaction with meteoric waters. Early stabilization of limestone components along the margin of the Amargosa basin apparently decreased susceptibility to subsequent dolomitization.

  12. Hydrologic monitoring of a waste-injection well near Milton, Florida, June 1975 - December 1976

    USGS Publications Warehouse

    Pascale, Charles A.; Martin, J.B.

    1977-01-01

    Hydraulic and chemical data were collected through a monitoring program conducted by the U.S. Geological Survey at an industrial liquid-waste injection site 6 mi southwest of Milton, Fla., in Santa Rosa County. The injection system is described. Data include injection rates, volumes, and pressures; water-level data at three monitor wells and a standby injection well, and field and laboratory analyses of water samples from four wells. Hydraulic and geochemical effects of the waste-injection system at the plant as of December 31, 1976, have been detected only in the injection zone, the lower limestone of the Floridan aquifer. Increased pressures are evident at the three wells used to monitor the injection zone. Geochemical changes have been noted only at the deep-test monitor well closest to the injection well. (Woodard-USGS)

  13. Dry Macular Degeneration

    MedlinePlus

    Dry macular degeneration Overview By Mayo Clinic Staff Dry macular degeneration is a common eye disorder among people over 65. ... vision in your direct line of sight. Dry macular degeneration may first develop in one eye and then ...

  14. A procedure to evaluate environmental rehabilitation in limestone quarries.

    PubMed

    Neri, Ana Claudia; Sánchez, Luis Enrique

    2010-11-01

    A procedure to evaluate mine rehabilitation practices during the operational phase was developed and validated. It is based on a comparison of actually observed or documented practices with internationally recommended best practices (BP). A set of 150 BP statements was derived from international guides in order to establish the benchmark. The statements are arranged in six rehabilitation programs under three categories: (1) planning (2) operational and (3) management, corresponding to the adoption of the plan-do-check-act management systems model to mine rehabilitation. The procedure consists of (i) performing technical inspections guided by a series of field forms containing BP statements; (ii) classifying evidences in five categories; and (iii) calculating conformity indexes and levels. For testing and calibration purposes, the procedure was applied to nine limestone quarries and conformity indexes were calculated for the rehabilitation programs in each quarry. Most quarries featured poor planning practices, operational practices reached high conformity levels in 50% of the cases and management practices scored moderate conformity. Despite all quarries being ISO 14001 certified, their management systems pay low attention to issues pertaining to land rehabilitation and biodiversity. The best results were achieved by a quarry whose expansion was recently submitted to the environmental impact assessment process, suggesting that public scrutiny may play a positive role in enhancing rehabilitation practices. Conformity indexes and levels can be used to chart the evolution of rehabilitation practices at regular intervals, to establish corporate goals and for communication with stakeholders.

  15. Transport studies of radon in limestone underlying houses

    SciTech Connect

    Gammage, R.B.; Dudney, C.S.; Wilson, D.L.; Saultz, R.J.

    1990-01-01

    In hilly limestone terrains of the southern Appalachians, subterranean networks of solution cavities and fissures present circulatory systems facilitating convective and advective transport of radon-bearing gas. Evidence suggests that the primary driving forces for transport are aerostatic pressure differentials created by the difference between the underground and the outside air temperatures. Examples are presented of houses experiencing elevated indoor radon levels as a consequence of communicating with such subsurface transportation systems. The location of a house near the upper or lower end of a subterranean-circulatory system seems to produce amplification of indoor radon levels in winter or summer, respectively. The transport mechanism for radon-bearing air in karst and its impact on indoor radon need better understanding, both in regard to evaluating the geographical prevalence of the phenomenon and the induced spatial and temporal effects that are possible. This paper reports field studies made at houses in karst regions at Oak Ridge, Tennessee, and Huntsville, Alabama. A primary radon-transport mechanism is advocated of ascending or descending subsurface columns of air whose flows are largely driven by aerostatic pressure gradients created by the inground-outdoor air temperature differentials. 5 refs., 5 figs., 1 tab.

  16. Factors affecting floral herbivory in a limestone grassland

    NASA Astrophysics Data System (ADS)

    Breadmore, Karen N.; Kirk, William D. J.

    1998-12-01

    The amount of herbivore damage to the petals of 41 species of herbaceous plant was surveyed from April to September in a limestone grassland in central England. Damage was recorded as the percentage of the petal area removed. Most damage was caused by invertebrates, particularly slugs. The amount of invertebrate damage differed significantly between plant species and with time of year. The mean damage across all species was only 2 %, ranging from an average of 0 % in Galium sterneri to 8 % in Primula vulgaris. In most species, less than a quarter of flowers received any damage, so those that were damaged were often severely affected. Species flowering early or late in the season received more damage, possibly because of greater slug activity. Hypotheses to explain the inter-specific variation in the amount of herbivory were examined by testing for correlations with a range of plant variables. No correlations with flower-stem length, flower-stem thickness or the longevity of flowers were apparent. The amount of petal damage correlated strongly with flower size and petal thickness. This appeared to result from the prevalence of large-flowered species early and late in the season rather than from a preference for flower size and petal thickness per se. The evolutionary significance of floral herbivory is discussed.

  17. Acid neutralization within limestone sand reactors receiving coal mine drainage.

    PubMed

    Watten, Barnaby J; Sibrell, Philip L; Schwartz, Michael F

    2005-09-01

    Pulsed bed treatment of acid mine drainage (AMD) uses CO2 to accelerate limestone dissolution and intermittent fluidization to abrade and carry away metal hydrolysis products. Tests conducted with a prototype of 60 L/min capacity showed effective removal of H+ acidity over the range 196-584 mg/L (CaCO3) while concurrently generating surplus acid neutralization capacity. Effluent alkalinity (mg/L CaCO3) rose with increases in CO2 (DC, mg/L) according to the model Alkalinity=31.22+2.97(DC)0.5, where DC was varied from 11-726 mg/L. Altering fluidization and contraction periods from 30s/30s to 10s/50s did not influence alkalinity but did increase energy dissipation and bed expansion ratios. Field trials with three AMD sources demonstrated the process is capable of raising AMD pH above that required for hydrolysis and precipitation of Fe3+ and Al3+ but not Fe2+ and Mn2+. Numerical modeling showed CO2 requirements are reduced as AMD acidity increases and when DC is recycled from system effluent.

  18. Acid neutralization within limestone sand reactors receiving coal mine drainage

    USGS Publications Warehouse

    Watten, B.J.; Sibrell, P.L.; Schwartz, M.F.

    2005-01-01

    Pulsed bed treatment of acid mine drainage (AMD) uses CO2 to accelerate limestone dissolution and intermittent fluidization to abrade and carry away metal hydrolysis products. Tests conducted with a prototype of 60 L/min capacity showed effective removal of H+ acidity over the range 196-584 mg/L (CaCO3) while concurrently generating surplus acid neutralization capacity. Effluent alkalinity (mg/L CaCO3) rose with increases in CO2 (DC, mg/L) according to the model Alkalinity = 31.22 + 2.97(DC)0.5, where DC was varied from 11-726 mg/L. Altering fluidization and contraction periods from 30 s/30 s to 10 s/50 s did not influence alkalinity but did increase energy dissipation and bed expansion ratios. Field trials with three AMD sources demonstrated the process is capable of raising AMD pH above that required for hydrolysis and precipitation of Fe3+ and Al3+ but not Fe2+ and Mn2+. Numerical modeling showed CO2 requirements are reduced as AMD acidity increases and when DC is recycled from system effluent. ?? 2005 Elsevier Ltd. All rights reserved.

  19. Mechanisms of time-dependent deformation in porous limestone

    NASA Astrophysics Data System (ADS)

    Brantut, Nicolas; Heap, Michael J.; Baud, Patrick; Meredith, Philip G.

    2014-07-01

    We performed triaxial deformation experiments on a water-saturated porous limestone under constant strain rate and constant stress (creep) conditions. The tests were conducted at room temperature and at low effective pressures Peff=10 and Peff=20 MPa, in a regime where the rock is nominally brittle when tested at a constant strain rate of 10-5 s-1. Under these conditions and at constant stress, the phenomenon of brittle creep occurs. At Peff=10 MPa, brittle creep follows similar trends as those observed in other rock types (e.g., sandstones and granites): only small strains are accumulated before failure, and damage accumulation with increasing strain (as monitored by P wave speeds measurements during the tests) is not strongly dependent on the applied stresses. At Peff=20 MPa, brittle creep is also macroscopically observed, but when the creep strain rate is lower than ≈10-7 s-1, we observe that (1) much larger strains are accumulated, (2) less damage is accumulated with increasing strain, and (3) the deformation tends to be more compactant. These observations can be understood by considering that another deformation mechanism, different from crack growth, is active at low strain rates. We explore this possibility by constructing a deformation mechanism map that includes both subcritical crack growth and pressure solution creep processes; the increasing contribution of pressure solution creep at low strain rates is consistent with our observations.

  20. Multispectral analysis of limestone, dolomite, and granite, Mill Creek, Oklahoma

    NASA Technical Reports Server (NTRS)

    Rowan, L. C.; Watson, K.

    1970-01-01

    Spectral reflectance and thermal emission data were collected at the Mill Creek, Oklahoma test site during NASA missions 132 and 133 in June 1970. The data were collected by three aircraft flown several times during the diurnal cycle at altitudes of 150 to 17,000 m above mean terrain. Reflectance of the main rock types (limestone, dolomite, and granite) was determined from the data collected using a 12-channel multispectral scanner during mission 133 and from thermal infrared images recorded during mission 132 on an RS-7 scanner from 17,000 m above terrain. A preliminary rock recognition map was generated automatically using data collected from 900 m above terrain. The discrimination provided by the map is reasonably accurate. Misidentification occurred in areas of unusually high dolomite reflectivity. High altitude thermal infrared (10 to 12 micrometers) images show regional folds and faults distinguished by the presence of thermally contrasting materials. Linear and curvilinear structural features two to three times smaller than the nominal 17 m resolution could be detected.

  1. Recovering fresh water stored in saline limestone aquifers.

    USGS Publications Warehouse

    Merritt, M.L.

    1986-01-01

    Numerical modeling techniques are used to examine the hydrogeologic, design, and management factors governing the recovery efficiency of subsurface fresh-water storage. The modeling approach permitted many combinations of conditions to be studied. A sensitivity analysis was used that consisted of varying certain parameters while keeping constant as many other parameters or processes as possible. The results show that a loss of recovery efficiency resulted from: 1) processes causing mixing of injected fresh water with native saline water (hydrodynamic dispersion); 2) processes or conditions causing the irreversible displacement of the injected fresh water with respect to the well (buoyancy stratification and background hydraulic gradients); or 3) processes or procedures causing injection and withdrawal flow patterns to be dissimilar (dissimilar injection and withdrawal schedules in multiple-well systems). Other results indicated that recovery efficiency improved considerably during the first several successive cycles, provided that each recovery phase ended whgen the chloride concentration of withdrawn water exceeded established criteria for potability (usually 250 milligrams per liter). Other findings were that fresh water injected into highly permeable or highly saline aquifers would buoy rapidly with a deleterious effect on recovery efficiency. -Author

  2. Ocean sequestration of carbon dioxide: modeling the deep ocean release of a dense emulsion of liquid Co2-in-water stabilized by pulverized limestone particles.

    PubMed

    Golomb, D; Pennell, S; Ryan, D; Barry, E; Swett, P

    2007-07-01

    The release into the deep ocean of an emulsion of liquid carbon dioxide-in-seawater stabilized by fine particles of pulverized limestone (CaCO3) is modeled. The emulsion is denser than seawater, hence, it will sink deeper from the injection point, increasing the sequestration period. Also, the presence of CaCO3 will partially buffer the carbonic acid that results when the emulsion eventually disintegrates. The distance that the plume sinks depends on the density stratification of the ocean, the amount of the released emulsion, and the entrainment factor. When released into the open ocean, a plume containing the CO2 output of a 1000 MW(el) coal-fired power plant will typically sink hundreds of meters below the injection point. When released from a pipe into a valley on the continental shelf, the plume will sink about twice as far because of the limited entrainment of ambient seawater when the plume flows along the valley. A practical system is described involving a static mixer for the in situ creation of the CO2/seawater/pulverized limestone emulsion. The creation of the emulsion requires significant amounts of pulverized limestone, on the order of 0.5 tons per ton of liquid CO2. That increases the cost of ocean sequestration by about $13/ ton of CO2 sequestered. However, the additional cost may be compensated by the savings in transportation costs to greater depth, and because the release of an emulsion will not acidify the seawater around the release point.

  3. Additive effects of acidification and mineralogy on calcium isotopes in Triassic/Jurassic boundary limestones

    NASA Astrophysics Data System (ADS)

    Jost, Adam B.; Bachan, Aviv; van de Schootbrugge, Bas; Brown, Shaun T.; DePaolo, Donald J.; Payne, Jonathan L.

    2017-01-01

    The end-Triassic mass extinction coincided with a negative δ13C excursion, consistent with release of 13C-depleted CO2 from the Central Atlantic Magmatic Province. However, the amount of carbon released and its effects on ocean chemistry are poorly constrained. The coupled nature of the carbon and calcium cycles allows calcium isotopes to be used for constraining carbon cycle dynamics and vice versa. We present a high-resolution calcium isotope (δ44/40Ca) record from 100 m of marine limestone spanning the Triassic/Jurassic boundary in two stratigraphic sections from northern Italy. Immediately above the extinction horizon and the associated negative excursion in δ13C, δ44/40Ca decreases by ˜0.8‰ in 20 m of section and then recovers to preexcursion values. Coupled numerical models of the geological carbon and calcium cycles demonstrate that this δ44/40Ca excursion is too large to be explained by changes to seawater δ44/40Ca alone, regardless of CO2 injection volume and duration. Less than 20% of the δ44/40Ca excursion can be attributed to acidification. The remaining 80% likely reflects a higher proportion of aragonite in the original sediment, based largely on high concentrations of Sr in the samples. Our study demonstrates that coupled models of the carbon and calcium cycles have the potential to help distinguish contributions of primary seawater isotopic changes from local or diagenetic effects on the δ44/40Ca of carbonate sediments. Differentiating between these effects is critical for constraining the impact of ocean acidification during the end-Triassic mass extinction, as well as for interpreting other environmental events in the geologic past.

  4. Humidification of flue gas to augment SO/sub 2/ capture by dry sorbents. Repprt for October 1985-July 1988 (Final)

    SciTech Connect

    Gooch, J.P.; Beittel, R.; Dimukes, E.B.; Dahlin, R.S.

    1989-03-01

    This report discusses, for a coal-burning power plant, using humidification of the flue gas in a low-temperature duct to increase SO/sub 2/ removal by dry calcium-based sorbents. In particular, humidification may be a desirable modification of EPA's LIMB process, which is based on injecting limestone or hydrated lime in the furnace; it could augment SO/sub 2/ removal by adding post-furnace removal to that occurring in the injection zone. The report covers work in post-furnace humidification, charge-augmented humidification, water vapor adsorption by lime (with and without additives), and mathematical modeling of humidification and SO/sub 2/ removal processes. From these investigations, it was concluded that, for enhancement of SO/sub 2/ capture at the Edgewater demonstration of LIMB, humidification by a water spray will be required. A spray of pure water would suffice if the frequency of collisions between sorbent particles and water droplets could be increased. Deliquescent additives that are known to enhance SO/sub 2/ capture by Ca(OH)/sub 2/ at low temperatures must operate to some extent by mechanisms other than deliquescence.

  5. Primary deforestation and regrowth on limestone slopes on Vancouver Island, British Columbia

    SciTech Connect

    Harding, K.A.; Ford, D.C. . Dept. of Geography)

    1992-01-01

    Limestones, well bedded and steeply dipping, are common in northern Vancouver Island. They have been glaciated and host a high density of postglacial karren (dissolution pits, grooves and troughs linked to underlying caves). There is rich, mature forest cover of western hemlock, silver fir and red cedar that is rooted in the karren or in overlying glacial deposits. Logging commenced around 1900 AD, intensifying after 1960 with clear cutting and (often) burning of slash. Impacts were investigated quantitatively by comparing sixteen limestone sites with eight on adjoining volcanic rocks. Some sites on each retained original forest, other were cleared. It was found that soil losses following logging are significantly greater on the limestones because of wash into karren (the epikarst zone). Regrowth is retarded on the limestones also; one site cleared in 1911 had regained approximately 17% of its original volume of timber 75 years later.

  6. Weight losses of marble and limestone briquettes exposed to outdoor environments in the eastern United States

    SciTech Connect

    Youngdahl, C.A.

    1987-08-01

    Weight losses of marble and limestone samples exposed to outdoor environments at field sites in the eastern United States have been monitored in studies initiated in 1984. The prodcedures are described, and the results are tabulated and discussed. A rate of marble loss approximately equivalent to 16 ..mu..m of surface recession per year was found in North Carolina, and losses of this order were also observed in New Jersey, New York, and Washington, DC. Limestone weight losses were much higher than for marble in the first year; loss of extraneous materials from the porous limestone appeared to be a likely contributor to the overall loss. The rate of limestone loss diminished in the second year, though it continued to be higher than for marble. Exposures are continuing in a planned 10-yr program of tests. 8 refs., 3 figs., 5 tabs.

  7. Remediation of acid mine drainage at the friendship hill national historic site with a pulsed limestone bed process

    USGS Publications Warehouse

    Sibrell, P.L.; Watten, B.; Boone, T.; ,

    2003-01-01

    A new process utilizing pulsed fluidized limestone beds was tested for the remediation of acid mine drainage at the Friendship Hill National Historic Site, in southwestern Pennsylvania. A 230 liter-per-minute treatment system was constructed and operated over a fourteen-month period from June 2000 through September 2001. Over this period of time, 50,000 metric tons of limestone were used to treat 50 million liters of water. The influent water pH was 2.5 and acidity was 1000 mg/L as CaCO3. Despite the high potential for armoring at the site, effluent pH during normal plant operation ranged from 5.7 to 7.8 and averaged 6.8. As a result of the high influent acidity, sufficient CO2 was generated and recycled to provide a net alkaline discharge with about 50 mg/L as CaCO3 alkalinity. Additions of commercial CO2 increased effluent alkalinity to as high as 300 mg/L, and could be a useful process management tool for transient high flows or acidities. Metal removal rates were 95% for aluminum (60 mg/L in influent), 50 to 90% for iron (Fe), depending on the ratio of ferrous to ferric iron, which varied seasonally (200 mg/L in influent), and <10% of manganese (Mn) (10 mg/L in influent). Ferrous iron and Mn removal was incomplete because of the high pH required for precipitation of these species. Iron removal could be improved by increased aeration following neutralization, and Mn removal could be effected by a post treatment passive settling/oxidation pond. Metal hydroxide sludges were settled in settling tanks, and then hauled from the site for aesthetic purposes. Over 450 metric tons of sludge were removed from the water over the life of the project. The dried sludge was tested by the Toxicity Characteristics Leaching Protocol (TCLP) and was found to be non-hazardous. Treatment costs were $43,000 per year and $1.08 per m 3, but could be decreased to $22,000 and $0.51 per m3 by decreasing labor use and by onsite sludge handling. These results confirm the utility of the new

  8. Dry mouth during cancer treatment

    MedlinePlus

    Chemotherapy - dry mouth; Radiation therapy - dry mouth; Transplant - dry mouth; Transplantation - dry mouth ... National Cancer Institute. Chemotherapy and you: support for people with cancer. Updated May 2007. ... ...

  9. Origin and Evolution of Limestone Caves of Chhattisgarh and Orissa, India: Role of Geomorphic, Tectonic and Hydrological Processes

    NASA Astrophysics Data System (ADS)

    Gautam, P. K.; Allu, N. C.; Ramesh, R.; Yadava, M. G.; Panigrahi, C. P.

    2014-12-01

    Carbonate rocks undergo karstic process and karst morphology is a key to understand the nature and genesis of caves. The primary energy source for the formation of karst landforms is hydrological cycle. Geomorphic features along with hydrological characteristics provide important information not only on karst formation but also climate and environmental conditions. In this paper, we present the tectonic and geomorphic features that played a role in evolution of caves located in Chhattisgarh and Orissa States of India. The geomorphic and tectonic aspects of Kotumsar, Kailash, and Gupteshwar caves are discussed in relation to the origin and evolution of these caves. Caves are located near the water falls. The area is folded and faulted along the Eastern Ghat Mobile Belt (EGMB) due to tectonic reactivation. Shaly-limestone beds exhibit vertical dipping near Gupteshwar cave, and steeply inclined near Kotumsar and Kailash caves. Indrāvati and Sabari/Kolab tributaries of the Godavari River drain the area. The landscape evolution and the origin of caves in the region is a multistage process, where the lithology, orogeny, fluvial action, and monsoon are the main agents, which is similar to the four state model (Ford and Ewers, 1978). The river basin evolution and regional tectonism also caused the initiation of karstification in the region. The evolution of caves is believed to have taken place in Pre-Pliocene under more humid conditions that coincided with the initiation of monsoon in India. Further, during the Quaternary wet-dry/cold-warm phases altered physical and chemical weathering of limestone rocks. Contrasting relief features of Bastar plateau have also helped the extensive cave formation in the region. The dissolution along weak planes initiated the openings of caves, further enlarged by geomorphic agents. Both monsoon and tectonics have caused fluctuations in water levels along river courses, which acted as active agents in evolution of caves.

  10. Size and performance of anoxic limestone drains to neutralize acdic mine drainagei

    USGS Publications Warehouse

    Cravotta, C.A.

    2003-01-01

    Acidic mine drainage (AMD) can be neutralized effectively in underground, anoxic limestone drains (ALDs). Owing to reaction between the AMD and limestone (CaCO3), the pH and concentrations of alkalinity and calcium increase asymptotically with detention time in the ALD, while concentrations of sulfate, ferrous iron, and manganese typically are unaffected. This paper introduces a method to predict the alkalinity produced within an ALD and to estimate the mass of limestone required for its construction on the basis of data from short-term, closed-container (cubitainer) tests. The cubitainer tests, which used an initial mass of 4 kg crushed limestone completely inundated with 2.8 L AMD, were conducted for 11 to 16 d and provided estimates for the initial and maximum alkalinities and corresponding rates of alkalinity production and limestone dissolution. Long-term (5-11 yr) data for alkalinity and CaCO3 flux at the Howe Bridge, Morrison, and Buck Mountain ALDs in Pennsylvania, USA, indicate that rates of alkalinity production and limestone dissolution under field conditions were comparable with those in cubitainers filled with limestone and AMD from each site. The alkalinity of effluent and intermediate samples along the flow path through the ALDs and long-term trends in the residual mass of limestone and the effluent alkalinity were estimated as a function of the computed detention time within the ALD and second-order dissolution rate models for cubitainer tests. Thus, cubitainer tests can be a useful tool for designing ALDs and predicting their performance.

  11. Size and performance of anoxic limestone drains to neutralize acidic mine drainage.

    PubMed

    Cravotta, Charles A

    2003-01-01

    Acidic mine drainage (AMD) can be neutralized effectively in underground, anoxic limestone drains (ALDs). Owing to reaction between the AMD and limestone (CaCO3), the pH and concentrations of alkalinity and calcium increase asymptotically with detention time in the ALD, while concentrations of sulfate, ferrous iron, and manganese typically are unaffected. This paper introduces a method to predict the alkalinity produced within an ALD and to estimate the mass of limestone required for its construction on the basis of data from short-term, closed-container (cubitainer) tests. The cubitainer tests, which used an initial mass of 4 kg crushed limestone completely inundated with 2.8 L AMD, were conducted for 11 to 16 d and provided estimates for the initial and maximum alkalinities and corresponding rates of alkalinity production and limestone dissolution. Long-term (5-11 yr) data for alkalinity and CaCO3 flux at the Howe Bridge, Morrison, and Buck Mountain ALDs in Pennsylvania, USA, indicate that rates of alkalinity production and limestone dissolution under field conditions were comparable with those in cubitainers filled with limestone and AMD from each site. The alkalinity of effluent and intermediate samples along the flow path through the ALDs and long-term trends in the residual mass of limestone and the effluent alkalinity were estimated as a function of the computed detention time within the ALD and second-order dissolution rate models for cubitainer tests. Thus, cubitainer tests can be a useful tool for designing ALDs and predicting their performance.

  12. Techniques to improve the economics of limestone FGDS

    SciTech Connect

    Bresowar, G.E.; Klingspor, J.

    1995-12-31

    Many utilities have evaluated the cost of scrubbing versus fuel switching in various plans and scenarios to determine the most economical means for meeting the requirements of the new law. Presently, the future cost of removing a ton of SO{sub 2} is based on fuel switching, and the market values are in the range of $150 - $250 per ton. The perceived cost of FGDS retrofits is $250 - $400 per ton for eastern medium to high sulfur coal. ABB has studied the overall costs of FGDS and has developed a series of cost reducing improvements. and innovations. The improvements are manifested in ABBs new limestone FGDS technology known by the code phrase {open_quote}Stealth FGDS{close_quotes}. Stealth promises low capital and operating cost, high removal efficiencies for SO{sub 2} and other pollutants, little or positive environmental and economic impact on the local community, salable or non-hazardous by-products, ease of retrofit, and exceptionally short installation schedules. The concepts are being demonstrated in one system at the Miles Generating Station of Ohio Edison Company. Bearing the name {open_quote}LS-2 Advanced SO, Scrubbing{close_quotes}, the Stealth scrubber at Niles is a 110 MWe turnkey, retrofit unit to be completed 20 months after the release of engineering. It will remove 20,000 or more tons per year of SO{sub 2} from the flue gases generated by both Unit 1 and Unit 2 boilers, producing wallboard-grade gypsum. Upon completion of a four month test program, the plant will be operated by Ohio Edison for a four to five year reliability demonstration period. The performance and economic projections for LS-2 scrubbers show the technology to be quite attractive relative to projections for fuel switching when installed in a manner similar to the installation plan for Niles. The description and basis for these economic projections are described in this paper.

  13. Mangrove plantation over a limestone reef - Good for the ecology?

    NASA Astrophysics Data System (ADS)

    Asaeda, Takashi; Barnuevo, Abner; Sanjaya, Kelum; Fortes, Miguel D.; Kanesaka, Yoshikazu; Wolanski, Eric

    2016-05-01

    There have been efforts to restore degraded tropical and subtropical mangrove forests. While there have been many failures, there have been some successes but these were seldom evaluated to test to what level the created mangrove wetlands reproduce the characteristics of the natural ecosystem and thus what ecosystem services they can deliver. We provide such a detailed assessment for the case of Olango and Banacon Islands in the Philippines where the forest was created over a limestone reef where mangroves did not exist in one island but they covered most of the other island before deforestation in the 1940s and 1950s. The created forest appears to have reached a steady state after 60 years. As is typical of mangrove rehabilitation efforts worldwide, planting was limited to a single Rhizophora species. While a forest has been created, it does not mimic a natural forest. There is a large difference between the natural and planted forests in terms of forest structure and species diversity, and tree density. The high density of planted trees excludes importing other species from nearby natural forests; therefore the planted forest remains mono-specific even after several decades and shows no sign of mimicking the characteristics of a natural forest. The planted forests provided mangrove propagules that invaded nearby natural forests. The planted forest has also changed the substratum from sandy to muddy. The outline of the crown of the planted forest has become smooth and horizontal, contrary to that of a natural forest, and this changes the local landscape. Thus we recommend that future mangrove restoration schemes should modify their methodology in order to plant several species, maintain sufficient space between trees for growth, include the naturally dominant species, and create tidal creeks, in order to reproduce in the rehabilitated areas some of the key ecosystem characteristics of natural mangrove forests.

  14. Laboratory-scale interaction between CO2-rich brine and limestone and sandstone under supercritical CO2 conditions

    NASA Astrophysics Data System (ADS)

    Garcia-Rios, Maria; Cama, Jordi; Luquot, Linda; Soler, Josep

    2014-05-01

    A test site for a prospective CO2 geological storage is situated in Hontomín (Burgos, northern Spain) with a reservoir rock that is composed of limestone (calcite) and sandstone (66 wt.% calcite, 28 wt.% quartz and 6 wt.% microcline). During and after CO2 injection, the resulting CO2-rich acid brine will likely promote the dissolution of carbonate minerals (calcite) and aluminosilicates (microcline). Since the reservoir Hontomín brine contains sulfate, gypsum (or anhydrite at depth) may precipitate. These coupled dissolution and precipitation reactions may induce changes in porosity and pore structure of the repository rocks. Percolations experiments with mechanically fractured cores (8.6 mm in diameter and 18 mm length) were performed under CO2 supercritical conditions (Pfluid = 150 bar; pCO2 ≡ 90 bar and T = 60 ºC) in order to evaluate and quantify variations in fracture permeability, preferential path formation and fracture volume. The brine sulfate content and the flow rate were varied. Regarding limestone, as the synthetic brines circulated through the fracture, the fracture permeability initially increased slowly, to thereafter increase rapidly. This change was due to a localized dissolution process (wormhole formation) along the core that occurred regardless gypsum precipitation. Nonetheless, the originated fracture volume in the sulfate-rich brine experiments was a factor of two smaller than that in sulfate-free brine experiments. Also, an increase in flow rate from 0.2 to 60 mL/h increased the volume of both dissolved calcite and precipitated gypsum. Regarding sandstone, permeability increased gradually with time. Nonetheless, this increase was not always continuous due to eventual fracture clogging. Formation of wormholes was observed. Acknowledgements This study was financed by CIUDEN (Ciudad de la Energía), the Compostilla OXYCFB300 project and the PANACEA project (European Community's Seventh Framework Programme FP7/2007-2013 under grant

  15. Direct sulfation of limestone based on oxy-fuel combustion technology

    SciTech Connect

    Chen, C.M.; Zhao, C.S.; Liu, S.T.; Wang, C.B.

    2009-10-15

    With limestone as the sorbent, the sulfation reaction can proceed via two different routes depending on whether calcination of the limestone takes place under the given reaction conditions. The direct sulfation reaction is defined as the sulfation reaction between sulfur dioxide (SO{sub 2}) and limestone in an uncalcined state. This reaction, based on oxyfuel combustion technology, was studied by thermogravimetric analysis. Surface morphologies of the limestone particles after sulfation were examined by a scanning electron microscope. Results show that there are more pores or gaps in the product layer formed by direct sulfation of limestone than by indirect sulfation, which can be attributed to the generation of carbon dioxide (CO{sub 2}) at a reaction interface. Compared with indirect sulfation, direct sulfation of limestone can yield much higher conversion and has a much higher reaction rate. For direct sulfation, the greater porosity in the product layer greatly reduces the solid-state ion diffusion distance, resulting in a higher reaction rate and higher conversion.

  16. Influence of limestone characteristics on mercury re-emission in WFGD systems.

    PubMed

    Ochoa-González, Raquel; Díaz-Somoano, Mercedes; Martínez-Tarazona, M Rosa

    2013-03-19

    This work evaluates the influence of the effect of the properties of limestones on their reactivity and the re-emission of mercury under typical wet scrubber conditions. The influence of the composition, particle size, and porosity of limestones on their reactivity and the effect of sorbent concentration, pH, redox potential, and the sulphite and iron content of the slurry on Hg(0) re-emission was assessed. A small particle size, a high porosity and a low magnesium content increased the high reactivity of the limestones. Moreover, it was found that the higher the reactivity of the sample the greater the amount of mercury captured in the scrubber. Although sulphite ions did not cause the re-emission of mercury from the suspensions of the gypsums, the limestones enriched in iron increased Hg(0) re-emission under low oxygen conditions. It was observed that the low pH values of the gypsum suspensions favored the cocapture of mercury because Fe(2+) formation was avoided. The partitioning of the mercury in the byproducts of the scrubber depended on the impurities of the limestones rather than on their particle size. No leaching of mercury from the gypsum samples occurred suggesting that mercury was either tightly bound to the impurities of the limestone or was transformed into insoluble mercury species.

  17. Reducing energy-related CO2 emissions using accelerated weathering of limestone

    USGS Publications Warehouse

    Rau, Greg H.; Knauss, Kevin G.; Langer, William H.; Caldeira, Ken

    2007-01-01

    The use and impacts of accelerated weathering of limestone (AWL; reaction: CO2+H2O+CaCO3→Ca2++2(HCO3-) is explored as a CO2 capture and sequestration method. It is shown that significant limestone resources are relatively close to a majority of CO2-emitting power plants along the coastal US, a favored siting location for AWL. Waste fines, representing more than 20% of current US crushed limestone production (>109 tonnes/yr), could provide an inexpensive or free source of AWL carbonate. With limestone transportation then as the dominant cost variable, CO2 mitigation costs of $3-$4/tonne appear to be possible in certain locations. Perhaps 10–20% of US point–source CO2 emissions could be mitigated in this fashion. It is experimentally shown that CO2 sequestration rates of 10-6 to 10-5 moles/sec per m2 of limestone surface area are achievable, with reaction densities on the order of 10-2 tonnes CO2 m-3day-1, highly dependent on limestone particle size, solution turbulence and flow, and CO2 concentration. Modeling shows that AWL would allow carbon storage in the ocean with significantly reduced impacts to seawater pH relative to direct CO2 disposal into the atmosphere or sea. The addition of AWL-derived alkalinity to the ocean may itself be beneficial for marine biota.

  18. Accelerated weathering of limestone for CO2 mitigation opportunities for the stone and cement industries

    USGS Publications Warehouse

    Langer, W.H.; Juan, C.A.S.; Rau, G.H.; Caldeira, K.

    2009-01-01

    Large amounts of limestone fines coproduced during the processing of crushed limestone may be useful in the sequestration of carbon dioxide (CO 2). Accelerated weathering of limestone (AWL) is proposed as a low-tech method to capture and sequester CO2 from fossil fuel-fired power plants and other point-sources such as cement manufacturing. AWL reactants are readily available, inexpensive, and environmentally benign. Waste CO 2 is hydrated with water to produce carbonic acid, which then reacts with and is neutralized by limestone fines, thus converting CO2 gas to dissolved calcium bicarbonate. AWL waste products can be disposed of in the ocean. Feasibility requires access to an inexpensive source of limestone and to seawater, thus limiting AWL facilities within about 10 km of the coastline. The majority of U.S. coastal power generating facilities are within economical transport distance of limestone resources. AWL presents opportunities for collaborative efforts among the crushed stone industry, electrical utilities, cement manufactures, and research scientists.

  19. Interpretation of well hydrographs in the karstic Maynardville Limestone at the Oak Ridge Y-12 Plant

    SciTech Connect

    Shevenell, L.A.; McMaster, B.W.

    1996-06-01

    The Maynardville Limestone in Oak Ridge, Tennessee underlies the southern portion of Bear Creek Valley (BCV), and is considered to be the primary pathway for groundwater leaving the Y-12 Plant boundaries. Sixty-seven percent of all wells drilled into the Maynardville Limestone have intersected at least one cavity, suggesting karst features may be encountered throughout the shallow (< 200 ft) portions of the Limestone. Because waste facilities at the Y-12 Plant are located adjacent to the Maynardville Limestone, contaminants could enter the karst aquifer and be transported in the conduit system. As part of an overall hydrologic characterization effort of this karst aquifer, 41 wells in the Maynardville Limestone were instrumented with pressure transducers to monitor water level changes (hydrographs) associated with rain events. Wells at depths between approximately 20 and 750 ft were monitored over the course of at least two storms in order that variations with depth could be identified. The wells selected were not exclusively completed in cavities but were selected to include the broad range of hydrologic conditions present in the Maynardville Limestone. Cavities, fractures and diffuse flow zones were measured at a variety of depths. The water level data from the storms are used to identify areas of quickflow versus slower flowing water zones. The data are also used to estimate specific yields and continuum transmissitives in different portions of the aquifer.

  20. Sedimentology and diagenesis of Miocene Lirio Limestone, Isla de Mona, Puerto Rico

    SciTech Connect

    Ruiz, H.; Gonzalez, L.A.; Budd, A.F. )

    1991-03-01

    Isla de Mona is a carbonate plateau, 50 mi west of Puerto Rico. The island lies on the southern portion of the Mona Platform. It is composed mostly of two Miocene carbonate units: Isla de Mona Dolomite overlain by Lirio Limestone. The Lirio Limestone was deposited on a sloping erosional surface over the Isla de Mona Dolomite. The Miocene Lirio Limestone consists mostly of backreef sands (packstones) with a reefal sequence (boundstones and grainstones) present in the southwestern portion of the island. The reefal sequence is made up mostly of Stylophora, Porites, and Millepora. Thin, discreet pockets of carbonate mud, rich in planktonic foraminifera and radiolarians and mixed with shallow benthic fauna/flora (foraminifera, echinoderms, red algae, and corals) interpreted as storm deposits, are found throughout the unit. An extensive reefal zone can be inferred to be present throughout the southwestern to southern portions of the Mona Platform. The Lirio Limestone is heavily karstified and is riddled with sinkholes on the plateau surfaces and caves around the periphery of the island. Caves are exposed around the periphery of the island, radiating from a depression in the central portions of the Lirio Limestone, near contacts with the Isla de Mona Dolomite, are partially dolomitized. The southwestern outcrops exhibit partial dolomitization throughout. The distribution of sinkholes, seaward caverns, and partial dolomitization of the lowermost Lirio Limestone suggests diagenetic modifications by meteoric fluids in central exposed portions of the island and by marine-meteoric fluids in the lowermost portions of the phreatic lens.

  1. BIOMASS DRYING TECHNOLOGIES

    EPA Science Inventory

    The report examines the technologies used for drying of biomass and the energy requirements of biomass dryers. Biomass drying processes, drying methods, and the conventional types of dryers are surveyed generally. Drying methods and dryer studies using superheated steam as the d...

  2. Comparative study of porous limestones used in heritage structures in Cyprus and in Hungary

    NASA Astrophysics Data System (ADS)

    Theodoridou, Magdalini; Ioannou, Ioannis; Rozgonyi-Boissinot, Nikoletta; Török, Ákos

    2015-04-01

    Porous limestone is widely used as construction material in the monuments of Cyprus and Hungary. The present study compares the physical properties of a bioclastic limestone from Cyprus and an oolitic limestone from Hungary. Petra Gerolakkou is a Pliocene limestone from Cyprus that originates from the district of Nicosia, the island's capital. It has been extensively used throughout the years in construction and restoration projects, particularly in the Nicosia area. Distinctive examples of its use can be found in the majority of the most important historic monuments in Nicosia, such as the Venetian walls and fortifications, churches (e.g. the Agia Sofia Cathedral), the archbishop and presidential palaces and a high number of other traditional buildings. The studied Miocene limestone from Hungary was exploited from Sóskút quarry (15-20 km W-SW to Budapest). The quarry provided stone for emblematic monuments of the capital of Hungary such as the Parliament building, Mathias Church, the Opera House and Citadella. In this study, mechanical parameters for both aforementioned stones, such as uniaxial compressive and tensile strengths, were tested under laboratory conditions. Their density, porosity and water absorption were also compared. The studied limestone from Cyprus exhibits porosity values within the range of 48-51%, apparent density between 1340 and 1400 kg/m3 and strength values under uniaxial compressive load between 1.2 and 2.8 MPa. This lithotype is also considered susceptible to salt decay, since an approximate mass loss of 12.5% is noted after 15 salt crystallization artificial weathering cycles. The porosity of the Hungarian limestone is in the order of 16-35%, the bulk density is 1600-1950 kg/m3, while the compressive strength is 2.5-15 MPa. Durability tests indicate that even after 10 freeze-thaw cycles the loss in strength is dramatic. Test results indicate that use of porous limestone in both countries is common and fabric strongly controls the

  3. Nomination of the Globigerina Limestone of the Maltese Islands as a "Global Heritage Stone Resource"

    NASA Astrophysics Data System (ADS)

    Cassar, JoAnn

    2016-04-01

    The Maltese Islands consist of two main islands, Malta and Gozo, as well as a small number of islets, and lie in the central Mediterranean Sea approximately 90 km south of Sicily. Although only 316 square kilometres in size, the Islands contain a rich concentration of archaeological sites and historic buildings, as well as vernacular architecture and modern buildings, for the most part built of the local Globigerina Limestone, which is one of the few natural resources of the Islands. This stone can be described as a typical "soft limestone", very easy to carve and shape. It forms part of the large family of Oligo-Miocene "soft limestones" widely diffused in the Mediterranean Basin. The Maltese Globigerina Limestone Formation is one of five main Formations, and varies in thickness from 20 to over 200 m. The material used for building is located stratigraphically in the lower part of the Globigerina Limestone Formation, called the Lower Globigerina Limestone. This Formation is stratified into thick beds at outcrop. Sections where bioturbation is concentrated often also occur. This limestone is fine-grained, yellow to pale grey in colour, almost wholly composed of the tests of globigerinid planktonic foraminifera. Petrographically, Globigerina Limestone can be described as a bioclastic packstone, with bioclastic wackestones also occurring. This limestone has always been used as the predominant building material in the Islands. The Maltese prehistoric Temples, which were constructed approximately 6000 years ago, bear testimony to this. Between 1530 and 1798 the Order of the Knights of St John built kilometres of fortifications in this same material to protect the Island from the expanding Ottoman Empire. Fortifications, impressive churches, auberges and palaces were built of this stone during this period. The capital city of Valletta, a rich and dense manifestation of Baroque architecture in Globigerina Limestone, is included on the UNESCO World Heritage List, as are

  4. Cohesive model applied to fracture propagation in Indiana Limestone

    NASA Astrophysics Data System (ADS)

    Dewers, T. A.; Rinehart, A. J.; Bishop, J. E.

    2014-12-01

    We apply a cohesive fracture (CF) model to results of short-rod (SR), notched 3-point-bend (N3PB) tests, and Brazil tests in Indiana Limestone. Calibration and validation of the model are performed within a commercial finite element modeling platform. By using a linear traction-displacement softening response for a defined fracture-opening displacement (w1) following peak tensile stress (σcrit), the CF model numerically lumps different spatially distributed inelastic processes occurring at and around fracture tips into a thin zone within an elastic domain. Both the SR and the N3PB test specimen geometries use a notch partway through the sample to control the location of fracture propagation. We develop a mesh for both the SR and N3PB geometries with a narrow cohesive zone in the center of notches. From the Brazil tests, we find a tensile splitting stress (σsplit) of 5.9 MPa. We use a σsplit as the peak tensile stress (σcrit) for all simulations. The Young's modulus (E) and the critical crack opening distance (w1) of the CF model are calibrated against the SR data. The model successfully captures the elastic, yield, peak, and initial and late failure behavior and compares favorably against the N3PB tests. Differences in force-displacement and crack propagation are primarily caused by: more mixed-mode (shear and opening) crack propagation in N3PB than in SR tests, causing a higher peak; and transition from compression (high E) to tension (low E) in a larger volume of the N3PB sample than in the SR geometry. This material is based upon work supported as part of the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number DE-SC0001114. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy

  5. Field and laboratory experiments on high dissolution rates of limestone in stream flow

    NASA Astrophysics Data System (ADS)

    Hattanji, Tsuyoshi; Ueda, Mariko; Song, Wonsuh; Ishii, Nobuyuki; Hayakawa, Yuichi S.; Takaya, Yasuhiko; Matsukura, Yukinori

    2014-01-01

    Field and laboratory experiments were performed to examine dissolution rates of limestone in stream flow. Field experiments were conducted in three stream sites (A-C) with different lithological or hydrological settings around a limestone plateau in the Abukuma Mts., Japan. Sites A and B are allogenic streams, which flow from non-limestone sources into dolines, and site C has a karst spring source. Tablets made of limestone from the same plateau with a diameter of 3.5 cm and a thickness of 1 cm were placed in the streams for 3 years (2008-2011) where alkalinity, pH and major cation concentrations were measured periodically. The saturation indices of calcite (SIc) of stream water were - 2.8 ± 0.4 at site A, - 2.5 ± 0.4 at site B and - 0.5 ± 0.4 at site C. Annual weight loss ratios for tablets were extremely high at site A (0.11-0.14 mg cm- 2 d- 1), high at site B (0.05 mg cm- 2 d- 1), and low at site C (0.005 mg cm- 2 d- 1). The contrasting rates of weight loss are mainly explained by chemical conditions of stream water. In addition, laboratory experiments for dissolution of limestone tablets using a flow-through apparatus revealed that flow conditions around the limestone tablet is another important factor for dissolution in the stream environment. These results revealed that limestone dissolves at a rapid rate where water unsaturated to calcite continuously flows, such as in an allogenic stream.

  6. Economic evaluation of limestone and lime flue-gas-desulfurization processes

    SciTech Connect

    Burnett, T.A.; Stephenson, C.D.; Sudhoff, F.A.; Veitch, J.D.

    1983-05-01

    The preliminary-grade economics (accuracy: -15%, +30%) of various alternative limestone scrubbing options (absorber type, with and without forced oxidation, and with and without adipic acid enhancemet) are examined using the current design and economic premises established for the continuing series of economic evaluations performed by TVA for EPA. The economics are projected using the Shawnee lime/limestone computer model, which is based on long-term operating data from the EPA Alkali Scrubbing Test Facility at the TVA Shawnee Steam Plant near Paducah, Kentucky. The capital investment for the base-case limestone scrubbing process (500 MW, 3.5% sulfur coal, 1979 NSPS, spray tower, forced oxidation, landfill) is $206/kW. The first-year and levelized annual revenue requirements are 10.59 and 15.09 mills/kWh, respectively. Costs for the equivalent limestone scrubbing process using a Turbulent Contact Absorber (TCA) are lower while those for the venturi - spray tower absorber are higher. The forced-oxidation landfill disposal option has a lower capital investment than the unoxidized pond disposal option for all cases studied; however, the first-year and levelized annual revenue requirements are slightly higher for the forced-oxidation landfill process for most coal applications. For the spray tower limestone process to achieve a specified SO/sub 2/ removal efficiency, it is more economical to increase the limestone stoichiometry and minimize the absorber L/G. The use of adipic acid or possibly dibasic acid (DBA) as an additive to enhance SO/sub 2/ removal in the limestone scrubbing process is an economically attractive option. The use of adipic acid remains economically attractive even if both a high unit cost and a high degradation factor for adipic acid are assumed. 176 references, 35 figures, 56 tables.

  7. Mineralogical characterization of the Shelburne Marble and the Salem limestone: Test stones used to study the effects of acid rain

    SciTech Connect

    McGee, E.S.

    1989-01-01

    The Salem Limestone and the Shelburne Marble are representative of limestones and marbles commonly used in buildings and monuments. Both stones are composed predominantly of calcite. The Salem Limestone is homogeneous in composition and mineralogic characteristics throughout the test block. The Shelburne Marble has compositionally homogeneous mineral phases, but the distribution of those phases within the test block is random. The mineralogy and physical characteristics of the Shelburne Marble and Salem Limestone test blocks described in the study provide a baseline for future studies of the weathering behavior of these stones. Because the Shelburne Marble and the Salem Limestone are representative of typical commercial marbles and limestones, they are likely to be useful in a consortium study of the effects of acid precipitation on these two types of building stones.

  8. Limestones as a paleobathymeter for reconstructing past seismic activities: Muroto-misaki, Shikoku, southwestern Japan

    NASA Astrophysics Data System (ADS)

    Iryu, Y.; Maemoku, H.; Yamada, T.; Maeda, Y.

    2009-03-01

    Muroto-misaki (Cape Muroto) is located at the southern tip of the eastern half of Shikoku, southwestern Japan and is ~ 100 km north of the Nankai Trough where the Philippine Sea Plate is being subducted beneath the Eurasian Plate. Therefore, the Muroto-misaki area has been seismically uplifted. Sedimentologic analyses were conducted on Holocene limestones that occur along the coast from Muroto-misaki to Meoto-iwa, located ~ 13 km north of the cape. The limestones are limited to less than 9.2 m in elevation. The limestones are up to 4.4 m in mean diameter, up to 0.5 m in thickness, and consist mainly of fossilized sessile organisms, including annelids, corals, bryozoans, encrusting foraminifers, barnacles, nongeniculate coralline algae, and, to a lesser extent, molluscs and peyssonneliacean algae. Acicular and equant cements are minor components. Acicular cements are found in semi-closed spaces between coralline algal crusts and their substrates. The modal composition of limestones was determined by a point-counting technique. Based on the biotic composition, the Holocene limestones can be classified into six types (Types I to VI). A comparison of the vertical distribution of these rock types with that of modern sessile organisms indicates that the top of Type I limestone, which is characterized by the occurrence of hermatypic corals, corresponds approximately to the mean low water springs when the limestones formed. A difference in the highest occurrence of Type I limestone between two sites may represent the variation in the total amount of uplift over the last 1000 to 1500 years, which resulted in an apparent northward decline of paleo-mean low water springs at a rate of ~ 10 cm/km. Therefore, the Holocene limestones are a good paleobathymeter to reconstruct past seismic activities in this area. This study shows that warm temperate carbonate deposits are as excellent recorders of geologic events, such as the timing and scale of repeated coseismic uplifts and

  9. Drenov Grič black limestone as a heritage stone from Slovenia

    NASA Astrophysics Data System (ADS)

    Kramar, Sabina; Rožič, Boštjan; Žbona, Nina; Bedjanič, Mojca; Mladenović, Ana

    2016-04-01

    The limestone known as Drenov Grič black limestone is considered one of the most beautiful Slovenian natural stones due to its homogenous black colour interwoven with white veins. Over the centuries it has been exploited from three major quarries west of Ljubljana, with the main quarry at Drenov Grič playing the primary role in supplying building material for the central parts of Slovenia. All the quarries are currently not active. In the area of Drenov grič, one locality of black limestone is protected - Kuclerjev kamnolom quarry. It has the status of 'valuable natural feature of national importance' and is protected as a natural monument. This well-stratified micritic limestone of Triassic (Carnian) age occurs in 10-80 cm thick beds, with thin marl interlayers. The stone contains abundant fossil bivalves and ostracods. Apart from calcite as the main component, dolomite, quartz, illite/muscovite and pyrite are also present. The limestone is relatively rich in carbonaceous and bituminous organic matter, which is responsible for the black colour of the stone. This component does not have any adverse effect on mechanical and physical characteristics. As the lime¬stone is dense, thus facilitating a good polish, it has been commercially considered as marble. The stone has been widely used in Slovenian monuments, not only in Ljubljana but also in other regions of Slovenia. Many inner and outdoor architectural elements were made of this limestone, particularly in the baroque period, which was known for the extensive use of black limestones also in other European countries. The most significant use of this limestone has been recorded in sculptured portals and altars. Some of the important buildings decorated utilising this stone, are the Ljubljana Cathedral, the St. James's Parish Church, and the Franciscan Church of the Annunciation, all of which are located in Ljubljana, some of them having been declared as cultural monuments of local or national importance. When

  10. Capsule report: Adipic acid-enhanced lime/limestone test results at the EPA alkali scrubbing test facility

    SciTech Connect

    Burbank, D.A.; Wang, S.C.

    1982-04-01

    The fifth in a series of reports describing the results of the Shawnee Lime and Limestone Wet Scrubbing Test Program, the report describes the results of adipic acid-enhanced limestone wet scrubbing systems. A primary objective of the program was to enhance sulfur oxide removal and improve the reliability and economics of lime and limestone wet scrubbing systems by use of adipic acid as a chemical additive.

  11. Tidal rhythmites infine-grained Carboniferous limestones, U.S.A.

    USGS Publications Warehouse

    Archer, A.W.; Feldman, H.R.

    1994-01-01

    Analyses of fine-grained limestones reveals that many exhibit fine-scale laminations. Laminations can be normally graded and consist of a coarser-grained lower part and a finer-grained upper part. The upper part can also contain finely disseminated organic material. Despite the similarities of such graded laminae to yearly varves and turbidites, it can be demonstrated by use of laminae-thickness periodicities that some graded laminae are reasonably interpreted as the product of tidal processes. Within siliciclastic systems, modern analogues of such processes are available for comparisons. In fine-grained facies of the Salem Limestone (Visean; Indiana, U.S.A.), periodicities observed within sequential-laminae thicknesses indicate a dominant control by neap-spring tidal processes. Similarly, laminae within limestones of the vertebrate-bearing Hamilton paleochannel (Stephanian; Kansas, U.S.) exhibit similar features, including fine-scale tidal bundles. This limestone is noted for the abundance of articulated fish fossils. Carbonates containing articulated fish from the Wild Cow Formation (Stephanian; New Mexico, U.S.), exhibit diffuse laminations; however, closely associated siliciclastic mudstones contain laminae that exhibit tidal periodicities. There are many similarities between tidal periodicities and patterns of lamination thicknesses of these rocks. A tidal interpretation for these rocks allows for localized, very rapid rates of deposition. Such rapid deposition may, in part, help to explain how articulated fish and other vertebrates can become preserved within such fine-grained limestones. ?? 1994.

  12. Actinobacterial diversity in limestone deposit sites in Hundung, Manipur (India) and their antimicrobial activities.

    PubMed

    Nimaichand, Salam; Devi, Asem Mipeshwaree; Tamreihao, K; Ningthoujam, Debananda S; Li, Wen-Jun

    2015-01-01

    Studies on actinobacterial diversity in limestone habitats are scarce. This paper reports profiling of actinobacteria isolated from Hundung limestone samples in Manipur, India using ARDRA as the molecular tool for preliminary classification. A total of 137 actinobacteria were clustered into 31 phylotypic groups based on the ARDRA pattern generated and representative of each group was subjected to 16S rRNA gene sequencing. Generic diversity of the limestone isolates consisted of Streptomyces (15 phylotypic groups), Micromonospora (4), Amycolatopsis (3), Arthrobacter (3), Kitasatospora (2), Janibacter (1), Nocardia (1), Pseudonocardia (1) and Rhodococcus (1). Considering the antimicrobial potential of these actinobacteria, 19 showed antimicrobial activities against at least one of the bacterial and candidal test pathogens, while 45 exhibit biocontrol activities against at least one of the rice fungal pathogens. Out of the 137 actinobacterial isolates, 118 were found to have at least one of the three biosynthetic gene clusters (PKS-I, PKS-II, NRPS). The results indicate that 86% of the strains isolated from Hundung limestone deposit sites possessed biosynthetic gene clusters of which 40% exhibited antimicrobial activities. It can, therefore, be concluded that limestone habitat is a promising source for search of novel secondary metabolites.

  13. Stratigraphy and diagenesis of the Mississippian Lodgepole Limestone, Williston Basin, North Dakota

    SciTech Connect

    Grover, P.W. )

    1996-01-01

    Stratigraphic correlation of the Lodgepole Limestone (Bottineau Interval) indicates a sequence of three clinoform-shaped wedges that filled in the early Williston Basin. To date four productive 100m thick mounds have been discovered in the Lodgepole Limestone at Dickinson Field. The mounds seem to have nucleated at the toe of slope of the first highstand system tract and were subsequently buried by the second highstand systems tract. By isopaching each of the systems tracts one can predict were other mounds might have nucleated. Burial depth of the Bakken Shale-Lodgepole Limestone contact grade from 0.6 km at the edge of the Williston Basin to 3.4 km in the center. With increased depth the basal Lodgepole Limestone shows three phases of dolomitization, which are: small clear early dolomite; later iron rich fracture filling saddle dolomite and a later iron rich dolomite that seems to follow stylolites. Pre-oil migration mineralization of the overlying limestone include minor amounts of: anhydrite, pyrite, iron poor sphalerite, late iron rich sphalerite, chalcopyrite and celestite.

  14. Stratigraphy and diagenesis of the Mississippian Lodgepole Limestone, Williston Basin, North Dakota

    SciTech Connect

    Grover, P.W.

    1996-12-31

    Stratigraphic correlation of the Lodgepole Limestone (Bottineau Interval) indicates a sequence of three clinoform-shaped wedges that filled in the early Williston Basin. To date four productive 100m thick mounds have been discovered in the Lodgepole Limestone at Dickinson Field. The mounds seem to have nucleated at the toe of slope of the first highstand system tract and were subsequently buried by the second highstand systems tract. By isopaching each of the systems tracts one can predict were other mounds might have nucleated. Burial depth of the Bakken Shale-Lodgepole Limestone contact grade from 0.6 km at the edge of the Williston Basin to 3.4 km in the center. With increased depth the basal Lodgepole Limestone shows three phases of dolomitization, which are: small clear early dolomite; later iron rich fracture filling saddle dolomite and a later iron rich dolomite that seems to follow stylolites. Pre-oil migration mineralization of the overlying limestone include minor amounts of: anhydrite, pyrite, iron poor sphalerite, late iron rich sphalerite, chalcopyrite and celestite.

  15. Economic evaluation of advanced limestone, Davy S-H, and Dowa Gypsum-producing FGD processes

    SciTech Connect

    Dotson, R.L.; Maxwell, J.D.; Burnett, T.A.

    1984-02-01

    Economic evaluations were made of three gypsum-producing FGD processes: advanced limestone (in-loop forced oxidation with adipic acid additive), Davy S-H (lime), and Dowa (aluminum sulfate, limestone). For a 500-MW power unit burning 3.5% sulfur coal and meeting the 1979 NSPS, capital investments in 1982 costs are 93 M$ (186 $/kW) for the advanced limestone process, 116 M$ (231 $/kW) for the Davy S-H process, and 121 M$ (243 $/kW) for the Dowa process. First-year annual revenue requirements in 1984 costs for these processes are 26, 33, and 32 M$ (9.4, 11.9, and 11.7 mills/kWh), respectively. The lower capital investment and annual revenue requirements of the advanced limestone process is due in part to the use of adipic acid, which allows partial scrubbing at 95% removal. The Davy S-H has slightly higher annual revenue requirements than the Dowa process because lime rather than limestone is used. Changes in power unit size and coal sulfur content affect the costs of all three processes similarly. The Davy S-H process is more sensitive to raw material costs because lime is used. Landfill waste disposal is a minor cost element in all three processes. 103 references, 26 figures, 30 tables.

  16. Effect of magnesium salts on the sulphation capacity of limestone slurry.

    PubMed

    Ozyuğuran, Ayşe; Altun-Ciftçioğlu, Gökçen; Karatepe, Nilgün; Ersoy-Meriçboyu, Ayşegül

    2006-01-01

    The effect of different magnesium salts such as MgO, MgSO(4).7H2O and Mg(OH)2 on the total sulphation capacities of limestone slurries prepared from five different limestone samples was investigated. Sulphation reactions of slurries were conducted at a constant temperature of 323 K in a gaseous mixture consisting of 5% O2, 10% CO2, 0.5% SO2 and a balance of nitrogene by volume. It was found that the total sulphation capacities of limestone slurries increased with the addition of MgO and Mg(OH)2 salts and decreased with the addition of MgSO4.7H2O salt. Depending on the chemical composition of the limestone samples the total sulphation capacities of limestone slurries were increased between 22.30% and 75.00% by MgO addition and between 23.70% and 69.00% by Mg(OH)2 addition.

  17. Fluoride removal from groundwater by limestone treatment in presence of phosphoric acid.

    PubMed

    Gogoi, Sweety; Nath, Suresh K; Bordoloi, Shreemoyee; Dutta, Robin K

    2015-04-01

    Fluoride removal from groundwater has been studied by addition of dilute phosphoric acid (PA) to the influent water before limestone treatment through laboratory plug-flow column experiments and bench-scale plug-flow pilot tests. In this PA-enhanced limestone defluoridation (PAELD) technique, fluoride is removed from 0.526 mM to 0.50-52.60 μM in 3 h with near neutral final pH. The presence of PA increases the fluoride removal capacity of limestone to 1.10 mg/g compared to 0.39 mg/g reported in its absence. The changes in fluoride removal with variation in initial PA concentration, initial fluoride concentration and the final pH have been found to be statistically significant with p < 0.05. The estimated recurring cost is US$ ≈0.58/m(3) water. Simple scrubbing and rinsing is a preferable method for regeneration of limestone as it is almost equally effective with lime or NaOH. Sorption of fluoride by calcium phosphates produced in situ in the reactor is the dominant mechanism of fluoride removal in the PAELD. Precipitation of CaF2 and sorption of fluoride by the limestone also contribute to the fluoride removal. High efficiency, capacity, safety, environment-friendliness, low cost and simplicity of operation make the PAELD a potential technique for rural application.

  18. Effect of magnesium salts on the sulphation capacity of limestone slurry

    SciTech Connect

    Ozyuguran, A.; Altun-Ciftcioglu, G.; Karatepe, N.; Ersoy-Mericboyu, A.

    2006-09-15

    The effect of different magnesium salts such as MgO, MgSO{sub 4}.7H{sub 2}O and Mg(OH){sub 2} on the total sulphation capacities of limestone slurries prepared from five different limestone samples was investigated. Sulphation reactions of slurries were conducted at a constant temperature of 323 K in a gaseous mixture consisting of 5% O{sub 2}, 10% CO{sub 2}, 0.5% SO{sub 2} and a balance of nitrogen by volume. It was found that the total sulphation capacities of limestone slurries increased with the addition of MgO and Mg(OH){sub 2} salts and decreased with the addition of MgSO{sub 4}.7H{sub 2}O salt. Depending on the chemical composition of the limestone samples the total sulphation capacities of limestone slurries were increased between 22.30% and 75.00% by MgO addition and between 23.70% and 69.00% by Mg(OH){sub 2} addition.

  19. Dietary adaptations of Assamese macaques (Macaca assamensis) in limestone forests in Southwest China.

    PubMed

    Huang, Zhonghao; Huang, Chengming; Tang, Chuangbin; Huang, Libin; Tang, Huaxing; Ma, Guangzhi; Zhou, Qihai

    2015-02-01

    Limestone hills are an unusual habitat for primates, prompting them to evolve specific behavioral adaptations to the component karst habitat. From September 2012 to August 2013, we collected data on the diet of one group of Assamese macaques living in limestone forests at Nonggang National Nature Reserve, Guangxi Province, China, using instantaneous scan sampling. Assamese macaques were primarily folivorous, young leaves accounting for 75.5% and mature leaves an additional 1.8% of their diet. In contrast, fruit accounted for only 20.1%. The young leaves of Bonia saxatilis, a shrubby, karst-endemic bamboo that is superabundant in limestone hills, comprised the bulk of the average monthly diet. Moreover, macaques consumed significantly more bamboo leaves during the season when the availability of fruit declined, suggesting that bamboo leaves are an important fallback food for Assamese macaques in limestone forests. In addition, diet composition varied seasonally. The monkeys consumed significantly more fruit and fewer young leaves in the fruit-rich season than in the fruit-lean season. Fruit consumption was positively correlated with fruit availability, indicating that fruit is a preferred food for Assamese macaques. Of seventy-eight food species, only nine contributed >0.5% of the annual diet, and together these nine foods accounted for 90.7% of the annual diet. Our results suggest that bamboo consumption represents a key factor in the Assamese macaque's dietary adaptation to limestone habitat.

  20. Limestone dissolution induced by fungal mycelia, acidic materials, and carbonic anhydrase from fungi.

    PubMed

    Li, Wei; Zhou, Peng-Peng; Jia, Li-Ping; Yu, Long-Jiang; Li, Xue-Li; Zhu, Min

    2009-01-01

    Microorganisms influence the dissolution of a number of minerals. Limestone is one of the most abundant rock types in karst areas, and is predominantly calcium carbonate. Two types of experimental systems were designed in this paper, to make comparisons of limestone dissolution rate among the acidic materials and extracellular carbonic anhydrase (CA) excreted by fungi and the enwrapping effect of fungal mycelia. One was the simulated experimental system containing microorganisms. Another was the simulated experimental system without microorganisms. Results of previous experiment indicated that the acidic materials and CA like enzymatic materials excreted by fungi and the enwrapping effect of fungal mycelia were important factors influencing limestone dissolution. In the three factors mentioned above, the dissolution effect was mycelia enwraping effect>acidic dissolution effect>CA enzymatic effect. The results of the second experiment demonstrated further that the limestone dissolution effect of the acidic materials excreted by fungi was stronger than that of CA excreted by fungi. Nevertheless, CA still played an important role in promoting the dissolution of limestone.

  1. Discrimination of reservoir dolostone within tight limestone using rock physics modeling and pre-stack parameters

    NASA Astrophysics Data System (ADS)

    Park, G.; Lee, B.; Lee, G.

    2013-12-01

    Dolostones may be differentiated from limestones based on various pre-stack seismic parameters as they are denser and faster. However, because the seismic properties of a rock are affected strongly by porosity, porous dolostones may not be significantly denser and faster than limestones. We computed various pre-stack parameters (P-impedance, S-impedance, Vp/Vs, Poisson's ratio, Lamé constants) for tight limestones using the Vp and density logs from a well that penetrated Jurassic carbonate and the Vs log, constructed from the empirical relationships of Vp and Vs. The pre-stack parameters of dolostones with 1% - 40% porosity were estimated based on the bulk and shear moduli and bulk densities computed from the formulas proposed by various workers, including Gassmann equations. Crossplots of the pre-stack parameters show that the Lamé constants (λ, μ) are most effective in differentiating dolostones from limestones. In particular, the λρ -μρ vs. μρ crossplot shows a clear-cut separation of the porous dolostones and tight limestones; the porous dolostones plot exclusively to the left of the λρ -μρ of about 25 GPa.

  2. Depositional facies and diagenetic history of Trenton Limestone in northern Indiana

    SciTech Connect

    Fara, D.R.; Keith, B.D.

    1984-12-01

    Subsurface cores were studied petrographically to determine the facies and diagenetic history of the Trenton Limestone on a regional scale in northern Indiana. The Trenton Limestone is a yellowish olive-gray fossiliferous limestone, which is replaced by a light-gray dolostone in northern Indiana. Facies composing the Trenton are: 1) bryozoan-echinoderm packstone, 2) bryozoan-echinoderm grainstone, 3) bryozoan packstone to wackestone, 4) lime mudstone, and 5) dolostone. The bryozoan-echinoderm packstone is the major facies. Coarse-grained (1-4 mm) grainstones are typically 1 ft (30 cm) thick, have abrupt bases, and become muddy upward. They are considered storm deposits. Hardgrounds occur throughout the limestone facies, but they are most numerous toward the base. These facies indicate deposition below wave base, interrupted by periods of high energy during storms. Fossiliferous white and gray chert nodules are scattered throughout the unit. Also found in the limestone facies are prevalent stylolites and microstylolites, an indication of chemical compaction. The dolostone facies consists of coarsely crystalline (0.4 mm) idiotopic dolomite. Pyrite is associated with the dolomite. Porosity, found only in the dolostone, is discontinuous and characterized as intercrystalline, vuggy, and moldic. Porous zones are commonly oil stained or have been plugged by poikilotopic selentic gypsum. Minor amounts of celestite are found as cavity fillings.

  3. Dry eye syndrome

    MedlinePlus

    ... of dry eyes include: Dry environment or workplace (wind, air conditioning) Sun exposure Smoking or second-hand ... NOT smoke and avoid second-hand smoke, direct wind, and air conditioning. Use a humidifier, especially in ...

  4. Exploratory and basic fluidized-bed combustion studies. Quarterly report, April-June 1980. [Limestone and dolomite; USA

    SciTech Connect

    Johnson, I.; Myles, K.M.; Swift, W.M.

    1980-12-01

    This work supports the development studies for both atmospheric and pressurized fluidized-bed coal combustion. Laboratory and process development studies are aimed at providing needed information on limestone utilization, removal of particles and alkali metal compounds from the flue gas, control of SO/sub 2/ and trace pollutant emissions, and other aspects of fluidized-bed coal combustion. This report presents information on: (1) the development of a sorbent utilization prediction methodology, (2) studies of factors which affect limestone breakup and elutriation, (3) basic studies of limestone sulfation under combustion conditions, and (4) studies of the kinetics of the hydration of spent limestone.

  5. Porosity development in the Copper Ridge Dolomite and Maynardville Limestone, Bear Creek Valley and Chestnut Ridge, Tennessee

    SciTech Connect

    Goldstrand, P.M.; Menefee, L.S.; Dreier, R.B.

    1995-12-01

    Matrix porosity data from deep core obtained in Bear Creek Valley indicate that porosities in the Maynardville Limestone are lithology and depth dependent. Matrix porosities are greater in the Cooper Ridge Dolomite than in the Maynardville Limestone, yet there is no apparent correlation with depth. Two interrelated diagenetic processes are the major controlling factors on porosity development in the Copper Ridge Dolomite and Maynardville Limestone; dissolution of evaporate minerals and dedolomitization. Both of these diagenetic processes produce matrix porosities between 2.1 and 1.3% in the Copper Ridge Dolomite and upper part of the Maynardville Limestone (Zone 6) to depths of approximately 600 ft bgs. Mean matrix porosities in Zones 5 through 2 of the Maynardville Limestone range from 0.8 to 0.5%. A large number of cavities have been intersected during drilling activities in nearly all zones of the Maynardville Limestone in Bear Creek Valley. Therefore, any maynardville Limestone zone within approximately 200 ft of the ground surface is likely to contain cavities that allow significant and rapid flow of groundwater. Zone 6 could be an important stratigraphic unit in the Maynardville Limestone for groundwater flow and contaminant transport because of the abundance of vuggy and moldic porosities. There are large variations in the thickness and lithology in the lower part of the Maynardville (Zones 2, 3, and 4 in the Burial Grounds region). The direction and velocity of strike-parallel groundwater flow may be altered in this area within the lower Maynardville Limestone.

  6. Improved Water Flooding through Injection Brine Modification

    SciTech Connect

    Robertson, Eric Partridge; Thomas, Charles Phillip; Morrow, Norman

    2003-01-01

    Crude oil/brine/rock interactions can lead to large variations in the displacement efficiency of waterflooding, by far the most widely applied method of improved oil recovery. Laboratory waterflood tests show that injection of dilute brine can increase oil recovery. Numerous fields in the Powder River basin have been waterflooded using low salinity brine (about 500 ppm) from the Madison limestone or Fox Hills sandstone. Although many uncertainties arise in the interpretation and comparison of field production data, injection of low salinity brine appears to give higher recovery compared to brine of moderate salinity (about 7,000 ppm). Laboratory studies of the effect of brine composition on oil recovery cover a wide range of rock types and crude oils. Oil recovery increases using low salinity brine as the injection water ranged from a low of no notable increase to as much as 37.0% depending on the system being studied. Recovery increases using low salinity brine after establishing residual oil saturation (tertiary mode) ranged from no significant increase to 6.0%. Tests with two sets of reservoir cores and crude oil indicated slight improvement in recovery for low salinity brine. Crude oil type and rock type (particularly the presence and distribution of kaolinite) both play a dominant role in the effect that brine composition has on waterflood oil recovery.

  7. Prediction of building limestone physical and mechanical properties by means of ultrasonic P-wave velocity.

    PubMed

    Concu, Giovanna; De Nicolo, Barbara; Valdes, Monica

    2014-01-01

    The aim of this study was to evaluate ultrasonic P-wave velocity as a feature for predicting some physical and mechanical properties that describe the behavior of local building limestone. To this end, both ultrasonic testing and compressive tests were carried out on several limestone specimens and statistical correlation between ultrasonic velocity and density, compressive strength, and modulus of elasticity was studied. The effectiveness of ultrasonic velocity was evaluated by regression, with the aim of observing the coefficient of determination r(2) between ultrasonic velocity and the aforementioned parameters, and the mathematical expressions of the correlations were found and discussed. The strong relations that were established between ultrasonic velocity and limestone properties indicate that these parameters can be reasonably estimated by means of this nondestructive parameter. This may be of great value in a preliminary phase of the diagnosis and inspection of stone masonry conditions, especially when the possibility of sampling material cores is reduced.

  8. Microfacies and diagenesis of Gua Bama limestone, Pahang Darul Makmur, Malaysia

    NASA Astrophysics Data System (ADS)

    Joeharry, Nelisa Ameera Mohamed; Ali, Che Aziz; Leman, Mohd Shafeea; Mohamed, Kamal Roslan

    2016-11-01

    Gua Bama limestone hill in Lipis District, Pahang State is a well-known site for the hunt of Malaysian Permo-Triassic Boundary. This paper details the microfacies and diagenesis of limestone succession at Gua Bama outcrop as an early effort to constrain the desired Permo-Triassic Boundary. Six microfacies have been identified: mudstone, peloidal wackestone, bioclastic wackestone, radiolarian wackestone, intraclastic packstone, and peloidal packstone. The appearance of highly diverse benthic fauna in fragmented forms and the dominance of mudstone-wackestone microfacies prove that carbonates of Gua Bama were deposited in low-energy shallow marine environment. Gua Bama have been subjected to multiple diagenetic processes, namely cementation, compaction, neomorphism, and micritization. Based on diagenetic textures observed, it can be interpreted that Gua Bama limestone had undergone diagenesis within marine water phreatic zone and deep burial realms.

  9. Stratigraphy and depositional history of the Iola Limestone Upper Pennsylvanian (Missourian), Northern Midcontinent U.S.

    NASA Astrophysics Data System (ADS)

    Mitchell, J. C.

    The Iola Limestone, one of the best developed and most laterally extensive, yet least studied Missourian cyclic carbonates in the Midcontinent Upper Pennsylvanian, was studied. Along with adjacent shales, five members constitute the Iola cyclothem, a typical Kansas cyclothem. In ascending order these are: Chanute Shale; Paola Limestone; Munice Creek Shale; Raytown Limestone; and Lane/Bonner Springs Shale. Although traditional interpretation of cyclothems regarded all shale as nearshore, shallow-water deposits, Iola lithology and stratigraphy support the more recent hypothesis that the cyclothem represents a single transgressive-regressive event, with maximum transgression occurring during deposition of the Muncie Creek Shale. Distribution of conodonts reflects the depositional pattern of the Iola cyclothem. Vertical variation far outweighs lateral variation in abundance and diversity.

  10. Reduction of soil pollution by usingwaste of the limestone in the cement industry

    NASA Astrophysics Data System (ADS)

    Muñoz, M. Cecilia Soto; Robles Castillo, Marcelo; Blanco Fernandez, David; Diaz Gonzalez, Marcos; Naranjo Lamilla, Pedro; Moore Undurraga, Fernando; Pardo Fabregat, Francisco; Vidal, Manuel Miguel Jordan; Bech, Jaume; Roca, Nuria

    2016-04-01

    In the cement manufacturing process (wet) a residue is generated in the flotation process. This builds up causing contamination of soil, groundwater and agricultural land unusable type. In this study to reduce soil and water pollution 10% of the dose of cement was replaced by waste of origin limestone. Concretes were produced with 3 doses of cement and mechanical strengths of each type of concrete to 7, 28 and 90 days were determined. the results indicate that the characteristics of calcareous residue can replace up to 10% of the dose of cement without significant decreases in strength occurs. It is noted that use of the residue reduces the initial resistance, so that the dose of cement should not be less than 200 kg of cement per m3. The results allow recommends the use of limestone waste since it has been observed decrease in soil and water contamination without prejudice construction material Keywords: Soil contamination; Limestone residue; Adding concrete

  11. Prediction of Building Limestone Physical and Mechanical Properties by Means of Ultrasonic P-Wave Velocity

    PubMed Central

    Concu, Giovanna; De Nicolo, Barbara; Valdes, Monica

    2014-01-01

    The aim of this study was to evaluate ultrasonic P-wave velocity as a feature for predicting some physical and mechanical properties that describe the behavior of local building limestone. To this end, both ultrasonic testing and compressive tests were carried out on several limestone specimens and statistical correlation between ultrasonic velocity and density, compressive strength, and modulus of elasticity was studied. The effectiveness of ultrasonic velocity was evaluated by regression, with the aim of observing the coefficient of determination r2 between ultrasonic velocity and the aforementioned parameters, and the mathematical expressions of the correlations were found and discussed. The strong relations that were established between ultrasonic velocity and limestone properties indicate that these parameters can be reasonably estimated by means of this nondestructive parameter. This may be of great value in a preliminary phase of the diagnosis and inspection of stone masonry conditions, especially when the possibility of sampling material cores is reduced. PMID:24511286

  12. Transport mechanisms and genesis of limestone clast conglomerates with examples from Cambrian of east Tennessee

    SciTech Connect

    Kozar, M.G.; Weber, L.J.; Walker, K.R.

    1986-05-01

    Limestone clast conglomerates are common sedimentary features of most Cambrian strata. Cambrian researchers have considered many of these conglomeratic deposits to have formed from erosion and redeposition of partially lithified sediments by storm currents in shallow subtidal and intertidal environments. Analysis of conglomeratic beds from the Middle and Late Cambrian (Maryville Limestone and Nolichucky Shale) in east Tennessee suggests that other, more dominant, processes were responsible for their genesis and transport. The proposed processes may serve as an alternative explanation for limestone clast conglomerates deposited elsewhere in Cambrian sequences. As the authors gain a greater understanding of transport mechanisms and their resultant sedimentary features, many of the conglomeratic beds that were once thought to be the result of storms may be reinterpreted as mass-gravity flows. Differentiating between these various types of transport mechanisms may be crucial to paleo-environmental interpretation.

  13. Franciscan complex calera limestones: Accreted remnants of farallon plate oceanic plateaus

    USGS Publications Warehouse

    Tarduno, J.A.; McWilliams, M.; Debiche, M.G.; Sliter, W.V.; Blake, M.C.

    1985-01-01

    The Calera Limestone, part of the Franciscan Complex of northern California, may have formed in a palaeoenvironment similar to Hess and Shatsky Rises of the present north-west Pacific1. We report here new palaeomagnetic results, palaeontological data and recent plate-motion models that reinforce this assertion. The Calera Limestone may have formed on Farallon Plate plateaus, north of the Pacific-Farallon spreading centre as a counterpart to Hess or Shatsky Rises. In one model2, the plateaus were formed by hotspots close to the Farallon_Pacific ridge axis. On accretion to North America, plateau dissection in the late Cretaceous to Eocene (50-70 Myr) could explain the occurrence of large volumes of pillow basalt and exotic blocks of limestone in the Franciscan Complex. Partial subduction of the plateaus could have contributed to Laramide (70-40 Myr) compressional events3. ?? 1985 Nature Publishing Group.

  14. Epilithic and endolithic bacterial communities in limestone from a Maya archaeological site.

    PubMed

    McNamara, Christopher J; Perry, Thomas D; Bearce, Kristen A; Hernandez-Duque, Guillermo; Mitchell, Ralph

    2006-01-01

    Biodeterioration of archaeological sites and historic buildings is a major concern for conservators, archaeologists, and scientists involved in preservation of the world's cultural heritage. The Maya archaeological sites in southern Mexico, some of the most important cultural artifacts in the Western Hemisphere, are constructed of limestone. High temperature and humidity have resulted in substantial microbial growth on stone surfaces at many of the sites. Despite the porous nature of limestone and the common occurrence of endolithic microorganisms in many habitats, little is known about the microbial flora living inside the stone. We found a large endolithic bacterial community in limestone from the interior of the Maya archaeological site Ek' Balam. Analysis of 16S rDNA clones demonstrated disparate communities (endolithic: >80% Actinobacteria, Acidobacteria, and Low GC Firmicutes; epilithic: >50% Proteobacteria). The presence of differing epilithic and endolithic bacterial communities may be a significant factor for conservation of stone cultural heritage materials and quantitative prediction of carbonate weathering.

  15. Optimization of limestone sizing for CFB combustors: Results of pilot plant and bench-scale testing

    SciTech Connect

    Alliston, M.; Edvardsson, C.; Wu, S.; Probst, S.

    1994-12-31

    A grant to study the performance of limestones in a Circulating Fluidized Bed Combustor was obtained in 1991 from the Pennsylvania Energy Development Authority (PEDA) by Tampella Power Corporation (TPC). The overall objective of this PEDA project was to carry out a systematic pilot plant tests at TPC`s pilot plant in Williamsport, Pennsylvania, in systematic order to identify ways of improving sulfur capture and limestone utilization through better control of the size distribution and residence time of the limestone particles in the furnace. It was also an objective to determine if bench scale testing could be of value in predicting CFB sorbent behavior. The pilot plant and bench test results were incorporated into an empirical Correlation which accounts for the size distribution and residence time of solids in CFB boiler.

  16. Freshwater biodissolution rates of limestone in the temperate climate of the Dinaric karst in Slovenia

    NASA Astrophysics Data System (ADS)

    Mulec, J.; Prelovšek, M.

    2015-01-01

    Dissolution rates in two freshwater karst systems were determined by using tablets of dense micrite-biopelmicrite Cretaceous limestone. Submerged limestone tablets in riverbeds were subjected to a natural gradient from complete darkness to direct sunlight. Higher light rates significantly (p < 0.05) increased the epilithic biomass of phototrophs and the overall dissolution rates, which were highest at the Unica spring (- 49.2 μm a- 1), but the exact portion of light-dependent dissolution remains elusive. In the karst river Unica, with its big fluctuations in environmental parameters (e.g., discharge), light rates can be used in estimating the dissolution rates enhanced by phototrophs. Natural biofilms in aquatic systems have important implications for landform evolution, and the impact on limestone dissolution rates is comparable with rates of debris falling from steep slopes.

  17. Weight losses of marble and limestone briquettes exposed to outdoor environments in the eastern United States

    SciTech Connect

    Reimann, K.J.

    1991-09-01

    Gravimetric changes in marble and limestone briquettes exposed to outdoor environment at five sites in the eastern United States have been monitored since 1984. An earlier report describes procedures and results obtained in 1984--1988. This report presents the results of the exposure period 1984--1988 and reviews and summarizes those of prior years. A linear relationship was found between cumulative gravimetric losses and exposure period or rain depth. These losses resulted in an average recession rate of 14 to 24 {mu}m/yr for marble and twice that for limestone. Variations in recession among the various exposure sites can be ascribed to differences in rain depth and hydrogen ion concentration. The annual recession rates obtained from gravimetry yielded rates that were for marble twice those obtained from runoff experiments, and more than three times those for limestone; this indicates that physical erosion plays an important role. Gravimetric monitoring of exposed briquettes is continuing in a planned 10-yr program.

  18. Effects of magnesium and chloride ions on limestone dual-alkali-system performance

    SciTech Connect

    Chang, J.C.S.; Kaplan, N.; Brna, T.G.

    1985-08-01

    The paper gives results of pilot plant tests to evaluate the effects of magnesium and chloride ions on system performance of limestone-regenerated dual alkali processes under closed-loop operating conditions. It was found that limestone reactivity and solids dewatering properties are very sensitive to magnesium ion concentrations. The total magnesium ion concentration should be maintained below 1000 ppm for satisfactory performance under normal operation. A model which assumes competitive surface adsorption of calcium and magnesium ions was used to interpret the data. Limestone reactivity and solids dewatering properties decreased with the increase of chloride ion concentrations; however, the effect of chloride ion accumulation was not significant until the concentration reached 80,000 ppm.

  19. Thermochemical degradation of limestone aggregate concrete on exposure to sodium fire

    NASA Astrophysics Data System (ADS)

    Premila, M.; Sivasubramanian, K.; Amarendra, G.; Sundar, C. S.

    2008-04-01

    Limestone aggregate concrete blocks were subjected to sodium fire conforming to a realistic scenario in order to qualify them as protective sacrificial layers over structural concrete flooring in liquid metal-cooled fast breeder reactors. Mid infrared absorption measurements were carried out on these sodium fire-exposed samples as a function of depth from the affected surface. Definite signatures of thermochemical degradation indicating dehydration and structural modification of the limestone concrete have been obtained. Control runs were carried out to delineate the thermal effects of sodium fires from that of the chemical interaction effects. Measurements on limestone aggregate samples treated with fused NaOH provided direct evidence of the exact mechanism of the sodium attack on concrete. The observed degradation effects were correlated to the mechanical strength of the concrete blocks and to the intensity of the sodium fire experienced.

  20. Epidural Injections for Spinal Pain

    MedlinePlus

    ... Physician Resources Professions Site Index A-Z Epidural Injections An epidural injection provides temporary or prolonged relief ... limitations of Epidural Injection? What is an Epidural Injection? An epidural injection is an injection of medication ...

  1. Use of borehole radar reflection logging to monitor steam-enhanced remediation in fractured limestone-results of numerical modelling and a field experiment

    USGS Publications Warehouse

    Gregoire, C.; Joesten, P.K.; Lane, J.W.

    2006-01-01

    Ground penetrating radar is an efficient geophysical method for the detection and location of fractures and fracture zones in electrically resistive rocks. In this study, the use of down-hole (borehole) radar reflection logs to monitor the injection of steam in fractured rocks was tested as part of a field-scale, steam-enhanced remediation pilot study conducted at a fractured limestone quarry contaminated with chlorinated hydrocarbons at the former Loring Air Force Base, Limestone, Maine, USA. In support of the pilot study, borehole radar reflection logs were collected three times (before, during, and near the end of steam injection) using broadband 100 MHz electric dipole antennas. Numerical modelling was performed to predict the effect of heating on radar-frequency electromagnetic (EM) wave velocity, attenuation, and fracture reflectivity. The modelling results indicate that EM wave velocity and attenuation change substantially if heating increases the electrical conductivity of the limestone matrix. Furthermore, the net effect of heat-induced variations in fracture-fluid dielectric properties on average medium velocity is insignificant because the expected total fracture porosity is low. In contrast, changes in fracture fluid electrical conductivity can have a significant effect on EM wave attenuation and fracture reflectivity. Total replacement of water by steam in a fracture decreases fracture reflectivity of a factor of 10 and induces a change in reflected wave polarity. Based on the numerical modelling results, a reflection amplitude analysis method was developed to delineate fractures where steam has displaced water. Radar reflection logs collected during the three acquisition periods were analysed in the frequency domain to determine if steam had replaced water in the fractures (after normalizing the logs to compensate for differences in antenna performance between logging runs). Analysis of the radar reflection logs from a borehole where the temperature

  2. Investigations of a Cretaceous limestone with spectral induced polarization and scanning electron microscopy

    NASA Astrophysics Data System (ADS)

    Johansson, Sara; Sparrenbom, Charlotte; Fiandaca, Gianluca; Lindskog, Anders; Olsson, Per-Ivar; Dahlin, Torleif; Rosqvist, Håkan

    2016-11-01

    Characterization of varying bedrock properties is a common need in various contexts, ranging from large infrastructure pre-investigations to environmental protection. A direct current resistivity and time domain induced polarization (IP) survey aiming to characterize properties of a Cretaceous limestone was carried out in the Kristianstad basin, Sweden. The time domain IP data was processed with a recently developed method in order to suppress noise from the challenging urban setting in the survey area. The processing also enabled extraction of early decay times resulting in broader spectra of the time decays and inversion for Cole-Cole parameters. The aim of this study is to evaluate the usefulness of Cole-Cole inverted IP data in early time ranges for bedrock characterization. The inverted sections showed variations within the limestone that are probably caused by variations in texture and composition. Samples from a deep drilling in the Kristianstad basin were investigated with scanning electron microscopy and energy dispersive X-ray spectroscopy, and the results showed that varying amounts of pyrite, glauconite and clay matrix were present at different levels in the limestone. The local high IP anomalies in the limestone could be caused by these minerals otherwise the IP responses were generally weak. There were also differences in the texture of the limestone at different levels, governed by fossil shapes and composition, proportions of calcareous cement and matrix as well as amount of silicate grains. Textural variations may have implications on the variation in Cole-Cole relaxation time and frequency factor. However, more research is needed in order to directly connect microgeometrical properties in limestone to spectral IP responses. The results from this study show that it is possible to recover useable spectral information from early decay times. We also show that under certain conditions (e.g. relatively short relaxation times in the subsurface), it is

  3. Magnetic characterization using a three-dimensional hysteresis projection, illustrated with a study of limestones

    NASA Astrophysics Data System (ADS)

    Borradaile, Graham J.; Lagroix, France

    2000-04-01

    Limestones provide an important source of palaeomagnetic information despite their low content of submicroscopic remanence-bearing minerals. The chief sources of these minerals are thought to be clastic volcanic magnetite and titanomagnetite, and organic magnetite, the latter mostly from bacterial sources. Chemically remagnetized limestones carry magnetite or pyrrhotite. Three hysteresis properties prove useful in identifying and characterizing these mineralogical influences on limestones: the ratio of zero-field maximum remanence to saturation remanence (Mr/Ms) in an applied field, coercivity of remanence (Bcr) and coercivity (Bc). To a lesser extent Kf/Ms may be useful, where Kf is the ferrimagnetic susceptibility. Traditionally, these have been plotted on a combination of 2-D graphs that of necessity only preserve two variables (Day et al. 1977; Wasilewski 1973). However, we found that magnetic discrimination and characterization of the limestones was much easier on a three-axis hysteresis projection that preserves the values of Bcr, Bc and Mr/Ms as independent variables. Using logarithmic scales, the regression surfaces through the data become almost planar and distinguish pelagic, shallow marine, shelf and remagnetized limestones on the basis of the slope and intercept of the associated regression surface. Clearly, there are sensitive sedimentological, geochemical or organic influences that dictate the magnetic mineralogy through sedimentary environment. Moreover, the 3-D plot of hysteresis criteria affords easy recognition of remagnetized limestones and may permit the rejection of material unsuitable for palaeomagnetic study. The 3-D hysteresis projection may be useful for the characterization of other rocks and magnetic materials

  4. Dry deposition velocities

    SciTech Connect

    Sehmel, G.A.

    1984-03-01

    Dry deposition velocities are very difficult to predict accurately. In this article, reported values of dry deposition velocities are summarized. This summary includes values from the literature on field measurements of gas and particle dry deposition velocities, and the uncertainties inherent in extrapolating field results to predict dry deposition velocities are discussed. A new method is described for predicting dry deposition velocity using a least-squares correlation of surface mass transfer resistances evaluated in wind tunnel experiments. 14 references, 4 figures, 1 table.

  5. Structure of drying costs

    SciTech Connect

    Sztabert, Z.T.

    1996-05-01

    A knowledge of cost structure and cost behavior is necessary in the management activities, particularly in the domain of investment or production decision making, as well as in the areas of production cost planning and control. Prediction and analysis of values of cost components for different technologies of drying are important when selection of a drying method and drying equipment should be done. Cost structures of lumber and coal drying processes together with an application of the factor method for prediction of the drying cost are presented.

  6. Dry building mixture with complex dispersed mineral additives

    NASA Astrophysics Data System (ADS)

    Il'ina, Liliia; Mukhina, Irina; Teplov, Alexandr

    2016-01-01

    The effectiveness of the complex dispersed mineral additive consisting of diopside and limestone was provided by the following factors. Diopside, due to the high hardness, reinforces formed hardened cement paste and prevents the spread of micro-cracks in it under the action of loads. Furthermore, diopside due to the greater elastic modulus than cement paste causes redistribution of stress between the additive particles and the cement. Limestone, since it has chemical affinity with the clinker minerals and products of their hydration hardening, effects on the hydration process and the formation of the contact area between the additive particles and the cement. The optimum quantity of complex dispersed mineral additive is 7%. At the same time the strength of the solution, made of dry building mixture "rough leveler for floor", increased by 22.1%, and the strength of the solution, made of dry mortar "masonry mixture" increased by 32.7%. With the mineral additive introduction the offset of the endoeffect temperatures to higher temperatures on derivatograms is fixed. If there is a mineral additive in the hardened cement paste, which may act as substrate for the tumors crystallization, the hardened cement paste structure strengthening while the complex thermal analysis is seen.

  7. Basalt-Limestone and Andesite-Limestone Interaction in the Arc Crust - Implications for Volcanic Degassing of CO2

    NASA Astrophysics Data System (ADS)

    Carter, L. B.; Dasgupta, R.

    2014-12-01

    Volcanically emitted CO2 is generally mantle-derived, but high degassing rates at some arcs (e.g. Merapi [1] and Colli Albani Volcanic District [2]) are thought to be affected by magma-carbonate interaction in the upper plate. However, the effects of depth, temperature, and composition on this process are poorly known. We experimentally simulated magma (50%)-limestone (50%) wallrock interactions at 0.5-1.0 GPa, 1100-1200 °C using pure calcite and a hydrous (~3-5 wt.% H2O) melt (basalt, andesite, or dacite). At 1.0 GPa, 1200 °C starting melts are superliquidus, whereas in the presence of calcite, Ca-rich cpx ± Ca-scapolite are produced. With increasing T, basalt-calcite interaction causes the melt, on a volatile-free basis, to become silica-poor and Ca-rich with alumina decreasing as cpx becomes more CaTs-rich. The same trend is seen with all starting melt compositions as P decreases at a constant T (1200 °C), producing melts similar to ultracalcic (CaO/Al2O3>>1) melt inclusions found in arc settings. Shifting from basalt to andesite has little effect on SiO2 and CaO of the reacted melt (e.g. 37 wt.% SiO2, 42 wt.% CaO at 0.5 GPa, 1200 °C), whereas Al2O3 of andesite-derived reacted melt is lower, likely a result of lower alumina in the starting andesite. Wall-rock calcite consumption is observed to increase with increasing T, decreasing P, and increasing melt XSiO2. At 0.5 GPa between 1100 and 1200 °C, our basalt experiments yield carbonate assimilation from 22 to 48 wt.%. This decreases to 20 wt.% at 1.0 GPa, 1200 °C, whereas an andesitic composition assimilates 59 to 52 wt.% from 0.5 to 1.0 GPa at 1200 °C. The higher assimilation in andesite-added runs at high-T is because of lower silicate liquidus as evidenced by lower modal proportion or absence of cpx ± scapolite. Using a magma flux rate estimated for Mt. Vesuvius [3], we obtain a CO2 outflux for a single such volcano experiencing arc magma-calcite reaction [4] of at least 2-4% of the present

  8. Rapid method to determine actinides and 89/90Sr in limestone and marble samples

    DOE PAGES

    Maxwell, Sherrod L.; Culligan, Brian; Hutchison, Jay B.; ...

    2016-04-12

    A new method for the determination of actinides and radiostrontium in limestone and marble samples has been developed that utilizes a rapid sodium hydroxide fusion to digest the sample. Following rapid pre-concentration steps to remove sample matrix interferences, the actinides and 89/90Sr are separated using extraction chromatographic resins and measured radiometrically. The advantages of sodium hydroxide fusion versus other fusion techniques will be discussed. Lastly, this approach has a sample preparation time for limestone and marble samples of <4 hours.

  9. Passive treatment of acid mine drainage in down-flow limestone systems

    SciTech Connect

    Watzlaf, G.R.

    1997-12-31

    Passive down-flow systems, consisting of compost and/or limestone layers, may be well suited for treatment of acidic mine drainage containing ferric iron and/or aluminum. Two columns were constructed and operated in the laboratory. The first column simulated a downward, vertical-flow anaerobic wetland, also referred to as successive alkalinity-producing systems (SAPS), and has received mine drainage for 97 weeks. The 0.16-m diameter column was vertically oriented and (from bottom to top) consisted of a 0.30-m thick layer of limestone, a 0.76-m thick layer of spent mushroom compost, and 0.91 m of free standing water. Water flowed vertically downward through the system. A second column, filled with only limestone, received water from the same source as the first column. This limestone column contained a 1.06-m thick layer of limestone and 0.91 m of free standing water and has received water for 55 weeks. Actual acid mine drainage (pH = 3.1, acidity = 200 mg/L (as CaCO{sub 3}), SO{sub 4}{sup 2-} = 600 mg/L, Total Fe = 10 mg/L, Mn = 14 mg/L, and Al = 18 mg/L) was collected every two weeks from a nearby abandoned deep mine and applied to these columns at a rate of 3.8 mL/min. For the compost/limestone column, effluent pH remained above 6.2 (6.2-7.9); however, pH at a depth of 0.38 m in the compost (halfway) dropped to < 4 after 28 weeks (net acidic). At the bottom of the compost pH remained > 4.5 for all 97 weeks. Alkalinity was generated by a combination of limestone dissolution and sulfate reduction. Over the 97 week period, the column generated an average of 330 mg/L of alkalinity, mostly due to limestone dissolution. Bacterial sulfate reduction displayed an ever decreasing trend, initially accounting for more than 200 mg/L of alkalinity and after 40 weeks only accounting for about 50 mg/L.

  10. Reducing Energy-Related CO2 Emissions Using Accelerated Limestone Weathering

    SciTech Connect

    Rau, G H; Knauss, K G; Langer, W H; Caldeira, K

    2004-04-27

    Following earlier descriptions, the use and impacts of accelerated weathering of limestone AWL; reaction: CO{sub 2} + H{sub 2}O + CaCO{sub 3} {yields} Ca{sup 2+} + 2(HCO{sub 3}{sup -}) as a CO{sub 2} capture and sequestration method is further explored. Since ready access to the ocean is likely an essential requirement for AWL, it is shown that significant limestone resources are relatively close to a majority of CO{sub 2}-emitting power plants along the coastal US. Furthermore, waste fines, representing more than 20% of current US crushed limestone production (>10{sup 9} tonnes/yr), could be used in many instances as an inexpensive or free source of AWL carbonate. With limestone transportation to coastal sites then as the dominant cost variable, CO{sub 2} sequestration (plus capture) costs of $3-$4/tonne are achievable in certain locations. While there is vastly more limestone and water on earth than that required for AWL to capture and sequester all fossil fuel CO{sub 2} production, the transportation cost of bringing limestone, seawater, and waste CO{sub 2} into contact likely limits the method's applicability to perhaps 10-20% of US point-source emissions. Using a bench-scale laboratory reactor, it is shown that CO{sub 2} sequestration rates of 10{sup -6} to 10{sup -5} moles/sec per m{sup 2} of limestone surface area are readily achievable using seawater. This translates into reaction densities as high as 2 x 10{sup -2} tonnes CO{sub 2} m{sup -3}day{sup -1}, highly dependent on limestone particle size, solution turbulence and flow, and CO{sub 2} concentration. Modeling of AWL end-solution disposal in the ocean shows significantly reduced effects on ocean pH and carbonate chemistry relative to those caused by direct CO{sub 2} disposal into the atmosphere or ocean. In fact the increase in ocean Ca{sup 2+} and bicarbonate offered by AWL should significantly enhance the growth of corals and other marine calcifiers whose health is currently being threatened by

  11. Accelerated weathering of limestone for CO2 mitigation: Opportunities for the stone and cement industries

    USGS Publications Warehouse

    Langer, William H.; San, Juan A.; Rau, Greg H.; Caldeira, Ken

    2009-01-01

    Accelerated weathering of limestone appears to provide a low-tech, inexpensive, high-capacity, environmentally friendly CO2 mitigation method that could be applied to about 200 fossil fuel fired power plants and about eight cement plants located in coastal areas in the conterminous U.S. This approach could also help solve the problem of disposal of limestone waste fines in the crushed stone industry. Research and implementation of this technology will require new collaborative efforts among the crushed stone and cement industries, electric utilities, and the science and engineering communities.

  12. Discrimination of moist oil shale and limestone using laser induced breakdown spectroscopy

    NASA Astrophysics Data System (ADS)

    Paris, P.; Piip, K.; Lepp, A.; Lissovski, A.; Aints, M.; Laan, M.

    2015-05-01

    Laser-induced plasma emission spectra of Estonian oil shale and associated limestone with varying moisture content were studied. Time gated spectra excited by 1064 nm laser radiation were recorded. Spectral lines for determination of plasma parameters were selected. Moisture causes the reduction of the intensity of the total emission, and increases the intensity of the Hα line. It was found that the effect of the moisture content on the plasma temperature and electron concentration was inconsiderable. Using the ratio of intensities of Hα and Mg spectral lines, it was possible to distinguish reliably between limestone and oil shale independently of their moisture content.

  13. Beam Injection into RHIC

    NASA Astrophysics Data System (ADS)

    Fischer, W.; Hahn, H.; Mackay, W. W.; Tsoupas, N.

    1997-05-01

    During the RHIC sextant test in January 1997 beam was injected into a sixth of one of the rings for the first time. We describe the injection zone and its bottlenecks, the application program to steer the beam and the injection kickers. We report on the commissioning of the injection systems and on measurements of the kickers.

  14. Experimental study of the SO{sub 2} removal efficiency and scale formation in limestone FGD process with lab and pilot test facility

    SciTech Connect

    Lee, S.Y.; Baek, J.J.; Kim, B.H.

    1997-12-31

    There are several tens of processes applied to Flue Gas Desulfurization (FGD) process in the world, which can be classified as wet, semi-dry and dry type. Among them, the wet type FGD is the most widely applied process for the large scale plant, such as power plant. The fundamental reasons of the preference for the wet type process are its high reliability and economic aspects. About 90% of the wet type process applied to actual plants is using the limestone -based gypsum process. Even though the limestone-based FGD process has simple construction and reliable SO{sub 2} removal efficiency, it has some problems in long-period continuous operation. Among these, the most serious one is the scaling. Scale is the solid mixture of reaction intermediate and by-product formed during various chemical reaction steps of FGD process. There are three types of scale in FGD absorber: calcium sulfite, gypsum, and CSS (Coprecipitated Calcium Sulfate and Sulfite). They have the tendency to precipitate on the absorber internals, such as packing, spray nozzles, mist eliminator, and surface of absorber itself, causing plugging, thus reducing the operation reliability. The major factor responsible for such problem is the lack of understanding for calcium sulfur salts chemistry, which occurred during the reaction steps of FGD process. In this study, the effect of operating conditions--gas velocity, gas temperature, SO{sub 2} concentration, L/G ratio, slurry concentration, etc.--on the SO{sub 2} removal efficiency and scale formation will be investigated. The scale formation mechanism will be studied to verify in a lab-scale test and the control method of scale for reliable operation will be established by the application of the lab-scale test result to pilot-scale facility test.

  15. Tests for injecting, storing, and recovering freshwater in a saline artesian aquifer, Lee County, Florida

    USGS Publications Warehouse

    Fitzpatrick, D.J.

    1986-01-01

    An investigation was made of the suitability of a saline, artesian limestone aquifer for the injection, storage, and recovery of freshwater from the Caloosahatchee River. The tests were conducted on a well tapping a leaky artesian system that has a transmissivity of 800 square feet per day, a storage of 1 x 10-4, and a leakance of 0.01 per day. The specific capacity of the injection well was increased through acidizing and was decreased as a result of well clogging during injection. Three injection tests were made wherein the amounts of freshwater injected, the storage duration, and the quality of water injected varied. Analysis of the test data showed that freshwater recoverability ranged from 9.7 to 38.7 percent of the total injected. Differences were attributed principally to differences in the quality of water injected and storage duration. Repeated injection-recovery cycles probably would result in greater recoverability. Head buildup, nearly 200 feet in one test, was a prime problem related chiefly to clogging from suspended material in the injected water and to bacterial growth at the wellbore-limestone interface. Regular backflushing was required. Total head buildup decreased as a result of acidizing the injection well. No coliforms or fecal streptococcus were noted in the recovered water. Growth of anaerobic bacteria occurred. Changes in the quality of the recovered water included decreases in concentration of dissolved organic carbon by as much as 15 mg/L (milligrams per liter), organic nitrogen by as much as 0.80 mg/L, and nitrate by as much as 0.50 mg/L. Increases were noted in ammonia by 0.40 mg/L, and iron by as much as 0.60 mg/L. These changes are consistent with the presence of an anaerobic bacterial ecosystem.

  16. Use of limestone obtained from waste of the mussel cannery industry for the production of mortars

    SciTech Connect

    Ballester, Paloma; Marmol, Isabel; Morales, Julian; Sanchez, Luis . E-mail: luis-sanchez@uco.es

    2007-04-15

    Various types of cement-SiO{sub 2}-CaCO{sub 3} mortar were prepared by replacing quarry limestone aggregate with limestone obtained as a by-product from waste of the mussel cannery industry. The CaCO{sub 3} aggregate consists mainly of elongated prismatic particles less than 4 {mu}m long rather than of the rounded particles of smaller size (2-6 {mu}m) obtained with quarry limestone. The mechanical and structural properties of the mortars were found to be influenced by aggregate morphology. Setting of the different types of mortar after variable curing times was evaluated by scanning electron microscopy (SEM), thermogravimetric analysis (TG) and mercury intrusion porosimetry (MIP) techniques. Mortars with a high content in mussel shell limestone exhibited a more packed microstructure, which facilitates setting of cement and results in improved mortar strength. The enhanced mechanical properties of the new mortars allow the cement content in the final mortar composition to be decreased and production costs to be reduced as a result.

  17. Effects of limestone petrography and calcite microstructure on OPC clinker raw meals burnability

    NASA Astrophysics Data System (ADS)

    Galimberti, Matteo; Marinoni, Nicoletta; Della Porta, Giovanna; Marchi, Maurizio; Dapiaggi, Monica

    2016-12-01

    Limestone represents the main raw material for ordinary Portland cement clinker production. In this study eight natural limestones from different geological environments were chosen to prepare raw meals for clinker manufacturing, aiming to define a parameter controlling the burnability. First, limestones were characterized by X-Ray Fluorescence, X-Ray Powder Diffraction and Optical Microscopy to assess their suitability for clinker production and their petrographic features. The average domains size and the microstrain of calcite were also determined by X-Ray Powder Diffraction line profile analysis. Then, each limestone was admixed with clay minerals to achieve the adequate chemical composition for clinker production. Raw meals were thermally threated at seven different temperatures, from 1000 to 1450 °C, to evaluate their behaviour on heating by ex situ X-Ray Powder Diffraction and to observe the final clinker morphology by Scanning Electron Microscopy. Results indicate the calcite microstrain is a reliable parameter to predict the burnability of the raw meals, in terms of calcium silicates growth and lime consumption. In particular, mixtures prepared starting from high-strained calcite exhibit a better burnability. Later, when the melt appears this correlation vanishes; however differences in the early burnability still reflect on the final clinker composition and texture.

  18. The Potential Use of Laser Ablation for Selective Cleaning of Indiana Limestone

    NASA Astrophysics Data System (ADS)

    Normandin, K. C.; Powers, L.; Slaton, D.; Scheffler, M. J.

    The aim of this investigation and conservation study was to examine and evaluate the laser ablation method as a practical technique for cleaning of Indiana limestone, a calcite-cemented stone widely used in historic structures throughout the United States. To this goal, a thorough petrographic characterization of the samples was performed prior to and following laser cleaning tests by Q-switched and short free running Nd:YAG lasers. The main optimization problem was the amber-gray appearance associated with the laser ablation by Q-switching lasers. Following the evaluation of such a cleaning result, two practicable solutions based on suitable pulse duration or wavelength selections were successfully demonstrated and then compared with different intervention protocols proposed. This chapter will show that through this case study, an understanding of effective uses of cleaning highly weathered Indiana limestone through the use of three types of Q-switched and short free running Nd:YAG lasers can be most effective in the removal from limestone of surface soiling and thick built-up carbon deposits ranging from 0.5 to 1mm in thickness. Case study evaluation methods included petrographic examination of composition, texture, and microstructure using optical microscopy and scanning electron microscopy performed on thin and polished sections of limestone sampled from six areas before and after cleaning. The microscopy studies were supplemented with energy-dispersive X-ray spectroscopy to characterize crystalline phases and track changes in chemistry.

  19. Treatment Of Metal-Mine Effluents By Limestone Neutralization And Calcite Co-Precipitation (Presentation)

    EPA Science Inventory

    The U.S. Geological Survey - Leetown Science Center and the Colorado School of Mines have developed a remediation process for the treatment of metals in circumneutral mining influenced waters. The process involves treatment with a pulsed limestone bed (PLB) system, followed by c...

  20. Treatment Of Metal-Mine Effluents By Limestone Neutralization And Calcite Co-Precipitation

    EPA Science Inventory

    The U.S. Geological Survey - Leetown Science Center and the Colorado School of Mines have developed a remediation process for the treatment of metals in circumneutral mining influenced waters. The process involves treatment with a pulsed limestone bed (PLB) system, followed by c...

  1. Hydrology of the cavernous limestones of the Mammoth Cave area, Kentucky

    USGS Publications Warehouse

    Brown, Richmond F.

    1966-01-01

    The Mammoth Cave National Park in central Kentucky offers a unique opportunity to study the occurrence of ground water in limestone under natural conditions. Ground water occurs as perched and semiperched bodies in alternate sandstone, shale, and limestone formations and under water-table conditions at the approximate level of the Green River in thick soluble limestone. Three continuous recorders that operated for 5 years indicate that precipitation on the Mammoth Cave plateau recharges the underlying sandstone rapidly. Ground water from the sandstone discharges horizontally to the edges of the plateau and vertically to underlying formations. Some of the precipitation recharges underlying formations almost immediately through overland flow to sinkholes and free fall through open shafts to pools at the water table. Much of the precipitation on the Pennyroyal plain flows overland into sinkholes and then through solution openings to the Green River. Water from the Green River flows into limestone solution channels under Mammoth Cave plateau at some stages, and this water discharges again to the Green River downstream. The presence of salt water, high in chloride in the Green River, makes it possible to trace the movement of the river water through the underground streams. Graphs show relationships of chloride concentration, stage of the Green River, time, precipitation, ground-water levels, and stratigraphy.

  2. Limestone characterization to model damage from acidic precipitation: Effect of pore structure on mass transfer

    USGS Publications Warehouse

    Leith, S.D.; Reddy, M.M.; Irez, W.F.; Heymans, M.J.

    1996-01-01

    The pore structure of Salem limestone is investigated, and conclusions regarding the effect of the pore geometry on modeling moisture and contaminant transport are discussed based on thin section petrography, scanning electron microscopy, mercury intrusion porosimetry, and nitrogen adsorption analyses. These investigations are compared to and shown to compliment permeability and capillary pressure measurements for this common building stone. Salem limestone exhibits a bimodal pore size distribution in which the larger pores provide routes for convective mass transfer of contaminants into the material and the smaller pores lead to high surface area adsorption and reaction sites. Relative permeability and capillary pressure measurements of the air/water system indicate that Salem limestone exhibits high capillarity end low effective permeability to water. Based on stone characterization, aqueous diffusion and convection are believed to be the primary transport mechanisms for pollutants in this stone. The extent of contaminant accumulation in the stone depends on the mechanism of partitioning between the aqueous and solid phases. The described characterization techniques and modeling approach can be applied to many systems of interest such as acidic damage to limestone, mass transfer of contaminants in concrete and other porous building materials, and modeling pollutant transport in subsurface moisture zones.

  3. Extreme limestone weathering rates due to micron-scale grain detachment

    NASA Astrophysics Data System (ADS)

    Emmanuel, Simon; Levenson, Yael

    2014-05-01

    Chemical dissolution is often assumed to control the weathering rates of carbonate rocks, although some studies have indicated that mechanical erosion could also play a significant role. Quantifying the rates of the different processes is challenging due to the high degree of variability encountered in both field and lab settings. To measure the rates and mechanisms controlling long-term limestone weathering, we analyse a lidar scan of the Western Wall, a Roman period edifice located in Jerusalem. Surface retreat rates in fine-grained micritic limestone blocks are found to be as much as 2 orders of magnitude higher than the average rates estimated for coarse-grained limestone blocks at the same site. In addition, in experiments that use atomic force microscopy to image dissolving micritic limestone, we show that these elevated reaction rates could be due to rapid dissolution along micron-scale grain boundaries, followed by mechanical detachment of tiny particles from the surface. Our analysis indicates that micron-scale grain detachment, rather than pure chemical dissolution, could be the dominant erosional mode for fine-grained carbonate rocks.

  4. Optimization of nanolime solvent for the consolidation of coarse porous limestone

    NASA Astrophysics Data System (ADS)

    Borsoi, Giovanni; Lubelli, Barbara; van Hees, Rob; Veiga, Rosário; Silva, António Santos

    2016-09-01

    The potentialities of nanomaterials for application in the field of conservation have been widely investigated in the last two decades. Among nanomaterials, nanolimes, i.e., dispersions of lime nanoparticles in alcohols are promising consolidating products for calcareous materials. Nanolimes are effective in recovering the very superficial loss of cohesion of decayed materials, but they do not always provide sufficient mass consolidation. This limitation is mainly related to the deposition of the nanoparticles nearby the surface of the material. Experimental research has been set up with the aim of improving the in-depth deposition of lime nanoparticles. Previous research by the authors has shown that nanolime deposition within a substrate can be controlled by adapting the nanolimes properties (kinetic stability and evaporation rate) to the moisture transport behavior of the substrate. Nanolime properties can be modified by the use of different solvents. In this research, nanolime dispersions have been further optimized for application on Maastricht limestone, a coarse porous limestone. Firstly, nanolimes were synthesized and dispersed in ethanol and/or water, both pure and mixed in different percentages. Subsequently, based on the kinetic stability of the nanolime dispersions, the most promising solvent mixtures were selected and applied on the limestone. The deposition of lime nanoparticles within the limestone was studied by phenolphthalein test, optical microscopy and scanning electron microscopy. The results confirm that nanolime dispersed in a mixture of ethanol (95 %) and water (5 %) can guarantee a better nanoparticles in-depth deposition within coarse porous substrates, when compared to dispersions in pure ethanol.

  5. Environmentally acceptable effect of hydrogen peroxide on cave "lamp-flora", calcite speleothems and limestones.

    PubMed

    Faimon, Jirí; Stelcl, Jindrich; Kubesová, Svatava; Zimák, Jirí

    2003-01-01

    Mosses, algae, and cyanobacteria (lamp-flora) colonize illuminated areas in show caves. This biota is commonly removed by a sodium hypochlorite solution. Because chlorine and other deleterious compounds are released into a cave environment during lamp-flora cleansing, hydrogen peroxide was tested as an alternative agent. In a multidisciplinary study conducted in the Kateinská Cave (Moravian Karst, Czech Republic), 12 algae- and cyanobacteria taxons and 19 moss taxons were detected. The threshold hydrogen peroxide concentration for the destruction of this lamp-flora was found to be 15 vol.%. Based on laboratory experiments in stirred batch reactors, the dissolution rates of limestones and calcite speleothems in water were determined as 3.77 x 10-3 and 1.81 x 10-3 mol m-2 h-1, respectively. In the 15% peroxide solution, the limestone and speleothem dissolution rates were one order of magnitude higher, 2.00 x 10-2 and 2.21 x 10-2 mol m-2 h-1, respectively. So, the peroxide solution was recognised to attack carbonates somewhat more aggressively than karst water. In order to prevent the potential corrosion of limestone and speleothems, the reaching of preliminary peroxide saturation with respect to calcite is recommended, for example, by adding of few limestone fragments into the solution at least 10 h prior to its application.

  6. Oxygen and carbon isotopic composition of limestones and dolomites, bikini and eniwetok atolls.

    PubMed

    Gross, M G; Tracey, J I

    1966-03-04

    Aragonitic, unconsolidated sediments from the borings on the Eniwetok and Bikini atolls are isotopically identical with unaltered skeletal fragments, whereas the recrystallized limestones exhibit isotopic variations resulting from alteration in meteoric waters during periods of emergence. Dolomites and associated calcites are enriched in O(18), perhaps because of interaction with hypersaline brines.

  7. The effect of elevated temperature on the strength parameters of silica acid ester consolidated porous limestones

    NASA Astrophysics Data System (ADS)

    Pápay, Zita; Török, Ákos

    2013-04-01

    The porous limestone is one of the most widespread construction materials of the monuments in Central Europe, with emblematic buildings in Vienna, Bratislava, Budapest and many other cities of Austria, Slovakia, Czech Republic and Hungary. The restoration of these monuments very often requires the consolidation of the porous limestone material, where various types of consolidants are used to strengthen the highly weathered stone. Our research focused on the understanding of the behaviour of consolidated porous limestone when the material is subjected to higher temperatures. Test procedure included the preparation of cylindrical test specimens from the Miocene porous limestone which was followed by consolidation by four various types of silica acid ester. The samples after consolidation were heated to 300 and 600 °C in electric oven. The material properties such as ultrasonic pulse velocity, density were tested before and after the treatment. Indirect tensile strength (Brazilian test) was used to compare the strength parameters of non treated and consolidated samples. Silica acid ester treated samples after heating were also measured in terms of strength, density and ultrasonic pulse velocity. The results show that there are significant changes in strength of various pre-treated samples after heating indicating the sensitivity of the materials to temperature changes and accidental fire.

  8. Use of glass fiber-reinforced plastic as an absorber in limestone wet flue gas desulfurization.

    PubMed

    Lin, Haibo

    2008-10-01

    The choice of materials for the spraying and oxidation of pipes directly affect the operation in limestone wet flue gas desulfurization (FGD). There is reason to consider using glass fiber-reinforced plastic (FRP) instead of expensive high nickel alloy for the spraying and oxidation of pipes.

  9. Demonstration of a hydration process for reactivating partially sulfated limestone sorbents

    SciTech Connect

    Smith, G.W.; Hajicek, D.R.; Myles, K.M.; Goblirsch, G.M.; Mowry, R.W.; Teats, F.G.

    1981-10-01

    The utilization of limestione sorbent for the removal of SO/sub 2/ in coal combustion in an atmospheric fluidized-bed combustor (AFBC) can be markedly increased by reactivating the partially sulfated limestone for reuse in the combustor. Such reuse would reduce costs and the environmental impact of quarrying and disposing of large quantities of limestone. The reactivation process consists of hydrating the partially sulfated limestone by treatment with water. A demonstration of the hydration process and the reuse of the reactivated limestone were carried out at Grand Forks Energy Technology Center (GFETC) in cooperation with Argonne National Laboratory (ANL). The data obtained in the GFETC 0.2-m/sup 2/ AFBC are compared with those obtained earlier in the ANL 0.02-m/sup 2/ AFBC. Marked enhancement of calcium utilization was achieved in both studies, but differences were noted in the degree of enhancement and in the Ca/S mole ratios required to maintain SO/sub 2/ in the off-gas at an acceptable level.

  10. The mechanics of intersecting echelon veins and pressure solution seams in limestone

    NASA Astrophysics Data System (ADS)

    Seyum, Solomon; Pollard, David D.

    2016-08-01

    Many studies that describe the formation of echelon vein arrays relate the causative stresses implicitly to the deformation, reliant on simple shear kinematics, such that the vein-to-array angle and the array width are the primary physical quantities. In contrast, we identify twelve physical quantities to describe echelon veins in two dimensions, including coeval, vein-intersecting, pressure solution seams. A finite element method is used to reproduce vein shapes in linear elastic and elastic-perfectly plastic model limestone. Model vein geometries are designed using values within the range of geometries measured from echelon veins at Raplee Anticline and Comb Monocline, Utah. Four physical quantities are significant for describing echelon vein shapes: vein spacing, vein-array angle, limestone elastic stiffness, and closing of orthogonal pressure solution seams. Pressure solution seam closing influences the mechanical interaction between adjacent veins, and for a range of conditions, causes a nearly linear vein opening distribution (triangular shapes) and encourages straight vein propagation, both of which approximate field measurements. Model results show that small spacing of veins with seams and large vein-array angles promote straight vein traces in limestone with stiffness typical of laboratory measurements, given the physical geologic conditions inferred from the burial history of the limestone strata.

  11. Adsorption/desorption of phosphorus on limestone from the Biscayne Aquifer under freshwater and seawater conditions.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Areas of seawater intrusion are known geochemically active regions particularly in limestone aquifers, where carbonate mineral dissolution and ion exchange reactions are important. Both of these processes can lead to a release of phosphorus from the aquifer matrix to the groundwater as seawater int...

  12. Facies development and paleoenvironment of the Hajajah Limestone Member, Aruma Formation, central Saudi Arabia

    NASA Astrophysics Data System (ADS)

    El-Sorogy, Abdelbaset S.; Ismail, Abdelmoneim; Youssef, Mohamed; Nour, Hamdy

    2016-12-01

    The Campanian Hajajah Limestone Member of the Aruma Formation was formed during two regressive episodes. Each of them formed of three depositional facies, from base to top: 1) intra-shelf basin facies, made up of fossiliferous green shale and mudstone with ostracods and badly preserved foraminifers. 2) fore-reef facies, consists of hard, massive, marly coralline limestone. The upper part is rich with low divers, badly to moderate preserved, solitary and colonial corals, and, 3) back reef and near-shore facies, consists of fossiliferous sandy dolomitized, bioturbated limestone with abundant reworked corals, bivalves, gastropods, and aggregate grains. On the basis of field observations, micro-and macrofossils and microfacies analysis, the Hajajah Limestone Member was deposited in distal marine settings below storm wave base in a low-energy environment changed upward to fore-reef framework in an open marine environment with moderate to high energy conditions and terminated with shallow marine facies with accumulation of skeletal grains by storms during regression.

  13. Performance Monitoring: Evaluating an Organic Carbon-Limestone PRB for Treatment of Heavy Metals and Acidity

    EPA Science Inventory

    Since 2004, researchers from the U.S. EPA National Risk Management Research Laboratory (NRMRL) have annually evaluated performance of an organic carbon-limestone permeable reactive barrier (PRB) system installed in 2003 by EPA Region 6 at the Delatte Metals Superfund site in Ponc...

  14. Ambient Dried Aerogels

    NASA Technical Reports Server (NTRS)

    Jones, Steven M.; Paik, Jong-Ah

    2013-01-01

    A method has been developed for creating aerogel using normal pressure and ambient temperatures. All spacecraft, satellites, and landers require the use of thermal insulation due to the extreme environments encountered in space and on extraterrestrial bodies. Ambient dried aerogels introduce the possibility of using aerogel as thermal insulation in a wide variety of instances where supercritically dried aerogels cannot be used. More specifically, thermoelectric devices can use ambient dried aerogel, where the advantages are in situ production using the cast-in ability of an aerogel. Previously, aerogels required supercritical conditions (high temperature and high pressure) to be dried. Ambient dried aerogels can be dried at room temperature and pressure. This allows many materials, such as plastics and certain metal alloys that cannot survive supercritical conditions, to be directly immersed in liquid aerogel precursor and then encapsulated in the final, dried aerogel. Additionally, the metalized Mylar films that could not survive the previous methods of making aerogels can survive the ambient drying technique, thus making multilayer insulation (MLI) materials possible. This results in lighter insulation material as well. Because this innovation does not require high-temperature or high-pressure drying, ambient dried aerogels are much less expensive to produce. The equipment needed to conduct supercritical drying costs many tens of thousands of dollars, and has associated running expenses for power, pressurized gasses, and maintenance. The ambient drying process also expands the size of the pieces of aerogel that can be made because a high-temperature, high-pressure system typically has internal dimensions of up to 30 cm in diameter and 60 cm in height. In the case of this innovation, the only limitation on the size of the aerogels produced would be in the ability of the solvent in the wet gel to escape from the gel network.

  15. Dry Snow Metamorphism

    DTIC Science & Technology

    2012-09-19

    REPORT Dry Snow Metamorphism Final Report Grant: 51065-EV 14. ABSTRACT 16. SECURITY CLASSIFICATION OF: The goal of this project was to characterize the...structural evolution of dry snow as it underwent metamorphism under either quasi-isothermal conditions or a temperature gradient, and to determine...Z39.18 - 5-Aug-2011 Dry Snow Metamorphism Final Report Grant: 51065-EV Report Title ABSTRACT The goal of this project was to characterize the structural

  16. Laboratory studies of Miocene limestone for the use of construction industry in Sri Lanka

    NASA Astrophysics Data System (ADS)

    de Silva Jayawardena, Upali

    2016-04-01

    Geologically ten percent of Sri Lanka is made up of Miocene limestone which covers northern and north-western coastal belt of the Island. It is used as a raw material for various industries but only cement and lime are being used for the construction industry. Except its chemical composition there is no available literature to study about other properties. Therefore the author carried out a series of laboratory tests to find out the mechanical properties of limestone in Sri Lanka. The objective of this paper is to make a note on the various properties of Miocene limestone and describe its suitability to use as an aggregate for the construction industry in Sri Lanka. Borehole samples (NX size) of limestone were obtained from various drilling sites in Northern Province of Sri Lanka and selected samples were prepared for different laboratory tests after visual observations. The tests were carried out according to ASTM Standards at the geotechnical and materials testing laboratories. The number of samples per each test was different. The range (and average result) for each property can be mentioned here as bulk density 2213-2643 (2452) kg/m3, water absorption 2.2-4.5 (1.91)%, porosity 1-15 (6.5)%, specific gravity 2.58-2.68(2.62), ultrasonic pulse velocity P wave 4480-6338 (5668) m/s and S wave 2688-3802 (3400) m/s, uniaxial compressive strength 11-92 (35)MPa, point load strength 1.2-7.1 (3.7)MPa, aggregate impact value, AIV 25-30 (28)%, LAAV 35-38 (36)%, and Brazilian tensile strength 2.1-4.4 (3.2)MPa. Poisson's ratio 0.12-0.68 (0.22) and modulus of elasticity 42-85 (62) GPa were obtained by using P and S ultrasonic wave velocity values. According to LAAV and AIV this limestone may be suitable as the base course material for road construction but may not be suitable for surface material of highways and rail road ballasts. Ultrasonic velocity waves indicate that limestone is highly compacted and solid. According to the compressive strength of solid limestone rock a few

  17. Investigations of a Cretaceous limestone with spectral induced polarization and scanning electron microscopy

    NASA Astrophysics Data System (ADS)

    Johansson, Sara; Sparrenbom, Charlotte; Fiandaca, Gianluca; Lindskog, Anders; Olsson, Per-Ivar; Dahlin, Torleif; Rosqvist, Håkan

    2017-02-01

    Characterization of varying bedrock properties is a common need in various contexts, ranging from large infrastructure pre-investigations to environmental protection. A direct current resistivity and time domain induced polarization (IP) survey aiming to characterize properties of a Cretaceous limestone was carried out in the Kristianstad basin, Sweden. The time domain IP data was processed with a recently developed method in order to suppress noise from the challenging urban setting in the survey area. The processing also enabled extraction of early decay times resulting in broader spectra of the time decays and inversion for Cole-Cole parameters. The aims of this study is to investigate if large-scale geoelectrical variations as well as small-scale structural and compositional variations exist within the Kristianstad limestone, and to evaluate the usefulness of Cole-Cole inverted IP data in early time ranges for bedrock characterization. The inverted sections showed variations within the limestone that could be caused by variations in texture and composition. Samples from a deep drilling in the Kristianstad basin were investigated with scanning electron microscopy and energy dispersive X-ray spectroscopy, and the results showed that varying amounts of pyrite, glauconite and clay matrix were present at different levels in the limestone. The local high IP anomalies in the limestone could be caused by these minerals otherwise the IP responses were generally weak. There were also differences in the texture of the limestone at different levels, governed by fossil shapes and composition, proportions of calcareous cement and matrix as well as amount of silicate grains. Textural variations may have implications on the variation in Cole-Cole relaxation time and frequency factor. However, more research is needed in order to directly connect microgeometrical properties in limestone to spectral IP responses. The results from this study show that it is possible to recover

  18. Three-Dimensional pore space and strain localization distribution in Majella limestone.

    NASA Astrophysics Data System (ADS)

    Ji, Yuntao; Hall, Stephen; Baud, Patrick; Wond, Teng-fong

    2015-04-01

    Brittle-ductile transition in porous rock is a topic of importance in many geological applications. Traditionally pore space in rock is characterized using optical and scanning electron microscopes (SEM). Advances in 3-dimensional imaging techniques such as X-ray computed tomography (CT) and laser scanning confocal microscopy have furnished enhanced perspective on pore geometry complexity. In particular, X-ray CT has been used widely for characterizing porous clastic rocks such as sandstone, whose void space is dominated by relatively equant pores connected by throats that are sufficiently large for direct imaging by X-ray microCT. However, standard techniques for CT imaging are not directly applicable to a carbonate rock because of the geometric complexity of its pore space. In this study, we first characterized the pore structure in Majella limestone. MicroCT data was partitioned into three distinct domains: macropores, solid grains and an intermediate domain made up of voxels of solid embedded with micropores below the resolution. A morphological analysis of the microCT images shows that both the solid and intermediate domains in Majella limestone are interconnected as it has been previously reported in a less porous limestone. We however show that the macroporosity in Majella limestone is fundamentally different, in that it has a percolative backbone which may contribute to significant enhancement of its permeability. We then present the first application of 3D-volumetric Digital Image Correlation (DIC) to a very porous limestone. If images of a rock sample are acquired before and after deformation, then DIC can be used to infer the displacement and strain fields. In our study, four Majella limestone samples were triaxially compressed at confining pressures ranging from 5 MPa to 25 MPa and another under hydrostatic conditions up to 60 MPa. For each of these five samples, two CT images were acquired before and after the deformation. We then used the Tomo

  19. The Öland limestone - A Swedish stone used for more than one thousand years

    NASA Astrophysics Data System (ADS)

    Schouenborg, Björn; Wickström, Linda; Mikaelsson, Jan

    2016-04-01

    The second largest island in Sweden is the home of the "Öland limestone", a condensed and bedded limestone whose origin dates back to Lower Ordovician, i.e. about 480 M years ago. Öland is a part of the palaeocontinent Baltica that, at the time, was situated at low latitudes with deposition of the calcareous sediments in a cool water environment. The limestone on Öland represents a proximal ramp tectonic setting, with the oldest sediments deposited in the west and younger sediments deposited towards east and southeast. Fluctuating sea-levels have created erosional hard grounds such as the Flowery sheet. These hardgrounds are recognised by their vivid colours and trace fossils, and can be traced all over Baltica, but is maybe best represented on Öland. Ordovician limestones are present in many places in Sweden, but it is the occurrence on Öland that is the most renowned in a building stone perspective. One reason for this is the favourable trading location, an island off the Swedish East coast in middle of the trading routes between the Baltic countries and the continent. Other reasons are the pleasant aesthetical values with numerous orthoceratites and other fossils. The limestones on Öland differ in colour. From the red varieties (with oxidized iron) to brownish and grey. The bedding is mostly in the cm-scale which easily enables very exploitable thickness of slabs. Every mm limestone represents about 1000 years of deposition. The limestone has most likely been used in a very crude way for many thousand years, but archaeological evidence of a more industrialized usage is just a little more than 1000 years. It is known from the literature that the first official Swedish king, Gustav Vasa (16th century), desired this stone. At the time it was called "Öland marble", and the king "imported" specialists to process it further at the Royal Stone workshop on northern Öland. Remnants of tools and working sites still remain in an outdoor museum. Export of the

  20. An integrated study of limestone behavior during calcination and hydration processes

    NASA Astrophysics Data System (ADS)

    Leontakianakos, George; Baziotis, Ioannis; Kiousis, George; Giavis, Dimitrios; Tsimas, Stamatios

    2010-05-01

    One of the most important processes in industrial scale, represents the dissociation of carbonates to lime and CO2. This process, called calcination, occur at relative high temperatures (>9000C). Lime rapidly reacts with the water, liberating high amounts of heat producing Ca(OH)2. For the purpose of the present study five samples of different limestones from different quarries from Greece were collected. The aim of the study was to analyze the behavior of the limestones during calcination and test the hydraulic properties of the quick lime. Limestone particles (1.6-2 cm) were reacted in a pre-heated oven at three different temperatures (900, 1050 and 1200oC) for 30 min in order to produce quick lime. Petrographic features of studied limestones were done using secondary electron microscopy (SEM). X-ray diffractometry and Raman micro-spectroscopy were applied in order to identify the carbonate phases (calcite and dolomite) in the studied limestones. Chemical composition of limestones and limes were determined by Atomic absorption spectroscopy (AAS) method. 25 gr of the produced lime were hydrated by adding 100 ml distilled water having a room temperature (~250C) to produce Ca(OH)2 through the exothermic reaction CaO(s) + H2O(l)-Ca(OH)2(aq). We measured the temperature difference in the water until a maximum value is reached; this value represents the reactivity of the produced slaked lime. Chemical composition and reactivity estimation were done following European Standards EN-459-2. The reactivity of quick lime depends on various factors with the most important being the internal structure of the limestone, calcination temperature/duration applied to the limestone, the admixtures such as the MgO content, hard-burned phenomena etc. The treatment of the experimental results suggests the following: i) The (CaO+MgO)Lime value have similar variation for both samples calcined at temperatures of 1050oC (58-90 wt%) and 1200oC (57-94 wt%); whereas the samples calcined at

  1. Evaluation of Different Modeling Approaches to Simulate Contaminant Transport in a Fractured Limestone Aquifer

    NASA Astrophysics Data System (ADS)

    Mosthaf, K.; Rosenberg, L.; Balbarini, N.; Broholm, M. M.; Bjerg, P. L.; Binning, P. J.

    2014-12-01

    It is important to understand the fate and transport of contaminants in limestone aquifers because they are a major drinking water resource. This is challenging because they are highly heterogeneous; with micro-porous grains, flint inclusions, and being heavily fractured. Several modeling approaches have been developed to describe contaminant transport in fractured media, such as the discrete fracture (with various fracture geometries), equivalent porous media (with and without anisotropy), and dual porosity models. However, these modeling concepts are not well tested for limestone geologies. Given available field data and model purpose, this paper therefore aims to develop, examine and compare modeling approaches for transport of contaminants in fractured limestone aquifers. The model comparison was conducted for a contaminated site in Denmark, where a plume of a dissolved contaminant (PCE) has migrated through a fractured limestone aquifer. Multilevel monitoring wells have been installed at the site and available data includes information on spill history, extent of contamination, geology and hydrogeology. To describe the geology and fracture network, data from borehole logs was combined with an analysis of heterogeneities and fractures from a nearby excavation (analog site). Methods for translating the geological information and fracture mapping into each of the model concepts were examined. Each model was compared with available field data, considering both model fit and measures of model suitability. An analysis of model parameter identifiability and sensitivity is presented. Results show that there is considerable difference between modeling approaches, and that it is important to identify the right one for the actual scale and model purpose. A challenge in the use of field data is the determination of relevant hydraulic properties and interpretation of aqueous and solid phase contaminant concentration sampling data. Traditional water sampling has a bias

  2. Evolution and extinction of Permian fusulinid fauna in the Khao Tham Yai Limestone in NE Thailand

    NASA Astrophysics Data System (ADS)

    Hada, Shigeki; Khosithanont, Somboon; Goto, Hiroya; Fontaine, Henri; Salyapongse, Sirot

    2015-05-01

    The first detailed biostratigraphic investigation of a single limestone unit within the Khao Tham Yai Limestone shows it was deposited continuously in a shelf setting without any intercalation of clastic beds. It ranges from the Wordian (middle Middle Permian) up to the Wuchiapingian (lower Upper Permian). The limestone unit is divided in ascending order into three fusulinid zones, i.e. Colania, Lepidolina and Codonofusiella zones. The middle zone is characterized by an abundance of large-tested fusulinids characteristic of the Lepidolina Zone. Shell sizes of the fusulinid species in this zone display continuous rapid morphological change along a one-way evolutionary path from small, primitive species with simple structure to large, highly evolved species having a complicated wall structure. Fusulinid biostratigraphy in a single limestone unit elucidates evolution and extinction patterns of Permian fusulinids of the shallow-water Tethyan shelf area in the Indochina Block. Our study reveals that the boundary between the Guadalupian (Middle Permian) and Lopingian (Upper Permian) in the Khao Tham Yai Limestone is clearly defined as an abrupt change in the fusulinid assemblages from the elimination of large-tested Verbeekinids and Schwagerinids to the domination of small-shelled Schubertellids. The Schubertellids underwent slower evolutionary morphological change than earlier fusulinids and were decreasingly dominant through the Permian. A similar pattern of fusulinid evolution and extinction at the Guadalupian-Lopingian boundary occurs in shallow-water Tethyan shelf areas and mid-oceanic shallow-water environments in mid-Panthalassa. Eventually, even smaller fusulinids abruptly become extinct. Clastic deposits finally replace previous carbonate formations characterized by algae-foraminifera biota. It starts in the upper Middle Permian in the southern parts and spreads throughout the whole area in the lower Upper Permian in NE Thailand. These observations suggest

  3. Indiana Corn Dry Mill

    SciTech Connect

    2006-09-01

    The goal of this project is to perform engineering, project design, and permitting for the creation and commercial demonstration of a corn dry mill biorefinery that will produce fuel-grade ethanol, distillers dry grain for animal feed, and carbon dioxide for industrial use.

  4. Tray Drying of Solids.

    ERIC Educational Resources Information Center

    Afacan, Artin; Masliyah, Jacob

    1984-01-01

    Describes a drying experiment useful in presenting the concept of simultaneous heat and mass transfer. Background information, equipment requirements, experimental procedures, and results are provided. The reasonably good agreement in the calculated rate of drying and that observed experimentally makes students feel confident in applying…

  5. Dry imaging cameras.

    PubMed

    Indrajit, Ik; Alam, Aftab; Sahni, Hirdesh; Bhatia, Mukul; Sahu, Samaresh

    2011-04-01

    Dry imaging cameras are important hard copy devices in radiology. Using dry imaging camera, multiformat images of digital modalities in radiology are created from a sealed unit of unexposed films. The functioning of a modern dry camera, involves a blend of concurrent processes, in areas of diverse sciences like computers, mechanics, thermal, optics, electricity and radiography. Broadly, hard copy devices are classified as laser and non laser based technology. When compared with the working knowledge and technical awareness of different modalities in radiology, the understanding of a dry imaging camera is often superficial and neglected. To fill this void, this article outlines the key features of a modern dry camera and its important issues that impact radiology workflow.

  6. Packaged kiln dried firewood

    SciTech Connect

    Cutrara, A.

    1986-07-01

    A process is described for kiln drying firewood consisting of essentially uniform lengths of split firewood pieces, the process comprising splitting essentially uniform lengths of green tree logs to form firewood pieces, placing the firewood pieces in open mesh bags to provide a plurality of bags of firewood, placing the plurality of bags of green firewood pieces in a kiln drying oven, kiln drying the pieces at temperatures in excess of 150/sup 0/F. by moving heated air over the pieces until the pieces have an overall moisture content ranging from 15% up to 30% by weight, operating the kiln at a temperature below a level which would render the structural characteristics of the bag useless and removing the kiln dried firewood pieces in the plurality of bags from the kiln drying oven.

  7. Velocity measurements in reservoir rock samples from a limestone unit using various pore fluids, and integration with well logs and seismic data

    NASA Astrophysics Data System (ADS)

    Purcell, Christopher C.

    One of the most promising methods proposed to mitigate excess global CO2 is carbon sequestration, a process in which CO2 is pressurized and injected into geologic formations. A technical challenge surrounding the geologic sequestration of CO2 is tracking the movement of the fluids pumped underground. Monitoring, verification and accounting activities related to CO2 storage are important for assuring that sequestered CO2 does not escape to the surface. Tracking this carbon dioxide can be considerably aided by reflection seismic-based detection methods. This thesis employs lab scale velocity measurements of core samples, under in situ reservoir pressure and temperature conditions, combined with multiple 3D reflection seismic surveys, to effectively track the movements of CO2 after injection. The National Energy Technology Laboratory (NETL) of the United States Department of Energy began to participate in research of an enhanced oil recovery project including the injection of CO2 deep into a reservoir structure, repeat reflection seismic surveys, collection of well logs, and rock physics analysis of sample core material. Our study is concentrated on a small area of this field around the injection site. At this site, hydrocarbons were previously moved via water injection. We obtained ultrasonic elastic wave velocity measurements that were conducted under several different saturation scenarios, including CO2 saturated samples, so a quantification of the conditions in different parts of the reservoir could be determined. This approach can help to characterize what is taking place inside the reservoir. Core-scale velocity measurements under in situ conditions allow us to predict changes in future well log or seismic surveys. The large amounts of CO2 accumulated over the past four decades in this reservoir give us a real world example of how an EOR site matures. Combining core scale, well log scale, and seismic scale measurements allows a better understanding of the

  8. Iron Sucrose Injection

    MedlinePlus

    Iron sucrose injection is used treat iron-deficiency anemia (a lower than normal number of red blood cells due ... and may cause the kidneys to stop working). Iron sucrose injection is in a class of medications called iron ...

  9. Antigen injection (image)

    MedlinePlus

    Leprosy is caused by the organism Mycobacterium leprae . The leprosy test involves injection of an antigen just under ... if your body has a current or recent leprosy infection. The injection site is labeled and examined ...

  10. Corticotropin, Repository Injection

    MedlinePlus

    ... age; episodes of symptoms in people who have multiple sclerosis (MS; a disease in which the nerves do ... When corticotropin repository injection is used to treat multiple sclerosis, it is usually injected once a day for ...

  11. Sodium Ferric Gluconate Injection

    MedlinePlus

    Sodium ferric gluconate injection is used to treat iron-deficiency anemia (a lower than normal number of ... are also receiving the medication epoetin (Epogen, Procrit). Sodium ferric gluconate injection is in a class of ...

  12. Amphotericin B Liposomal Injection

    MedlinePlus

    Amphotericin B liposomal injection is used to treat fungal infections such as cryptococcal meningitis (a fungal infection of the ... infections in people who cannot receive conventional amphotericin B therapy. Amphotericin B liposomal injection is in a ...

  13. Calcitonin Salmon Injection

    MedlinePlus

    Calcitonin salmon injection is used to treat osteoporosis in postmenopausal women. Osteoporosis is a disease that causes bones to weaken and break more easily. Calcitonin salmon injection is also used to ...

  14. Urinary incontinence - injectable implant

    MedlinePlus

    Intrinsic sphincter deficiency repair; ISD repair; Injectable bulking agents for stress urinary incontinence ... Urine leakage that gets worse Pain where the injection was done Allergic reaction to the material Implant ...

  15. Slit injection device

    DOEpatents

    Alger, Terry W.; Schlitt, Leland G.; Bradley, Laird P.

    1976-06-15

    A laser cavity electron beam injection device provided with a single elongated slit window for passing a suitably shaped electron beam and means for varying the current density of the injected electron beam.

  16. Hip joint injection

    MedlinePlus

    ... this page: //medlineplus.gov/ency/article/007633.htm Hip joint injection To use the sharing features on this ... injection is a shot of medicine into the hip joint. The medicine helps relieve pain and inflammation. It ...

  17. Aminocaproic Acid Injection

    MedlinePlus

    Aminocaproic acid injection is used to control bleeding that occurs when blood clots are broken down too quickly. This ... the baby is ready to be born). Aminocaproic acid injection is also used to control bleeding in ...

  18. Deoxycholic Acid Injection

    MedlinePlus

    Deoxycholic acid injection is used to improve the appearance and profile of moderate to severe submental fat ('double chin'; fatty tissue located under the chin). Deoxycholic acid injection is in a class of medications called ...

  19. Rich catalytic injection

    DOEpatents

    Veninger, Albert

    2008-12-30

    A gas turbine engine includes a compressor, a rich catalytic injector, a combustor, and a turbine. The rich catalytic injector includes a rich catalytic device, a mixing zone, and an injection assembly. The injection assembly provides an interface between the mixing zone and the combustor. The injection assembly can inject diffusion fuel into the combustor, provides flame aerodynamic stabilization in the combustor, and may include an ignition device.

  20. Passive treatment of acid mine drainage in systems containing compost and limestone: Laboratory and field results

    SciTech Connect

    Watzlaf, G.R.; Pappas, D.M.

    1996-12-31

    Passive, down-flow systems, consisting of compost and limestone layers, termed successive alkalinity producing systems (SAPS), may be well suited for treatment of mine drainage containing ferric iron and/or aluminum. A column, simulating a SAPS, has been operated in the laboratory for 52 weeks. The 0.16-m diameter column consisted of a 0.30-m thick layer of limestone, a 0.76-m thick layer of spent mushroom compost thick layer of limestone, a 0.76-m thick layer of spent mushroom compost and 0.91 m of free standing water. Actual AMD (pH = 3.02, acidity = 218 mg/L (as CaCO{sub 3}), SO{sub 4} = 600 mg/L, Fe = 16.0 mg/L, Mn = 12.1 mg/L, and Al = 17.1 mg/L) was applied to the column at a rate of 3.8 mL/min. Effluent pH has remained above 6.2 (6.2-7.9) in the column system. A SAPS located in Jefferson County, PA has been monitored for the past 4.5 years. The SAPS has an approximate area of 1000 m{sup 2} and contains a 0.4-m thick layer of limestone, a 0.2-m thick layer of spent mushroom compost, and 1.5 m of free standing water. Mine water (acidity = 335 mg/L (as CaCO{sub 3}), SO{sub 4} = 1270 mg/L, Fe = 246 mg/L, Mn = 38.4 mg/L, and Al = <0.2 mg/L) flowed into the SAPS at a rate of 140 L/min. Water samples from the field and laboratory systems have been collected at strategic locations on a regular basis and analyzed for pH, alkalinity, acidity, Fe{sup 2+}, total Fe, Mn, Al, SO{sub 4}, Ca, Mg, Na, Co, Ni, and Zn. Alkalinity has been generated in both field and laboratory systems by a combination of limestone dissolution and sulfate reduction. The column generated an average of 378 mg/L of alkalinity; 74% due to limestone dissolution and 26% due to bacterial reduction of sulfate. The field SAPS generated an average of 231 mg/L of alkalinity and exhibited seasonal trends.

  1. Preservation of extraterrestrial 3He in 480-Ma-old marine limestones.

    PubMed

    Patterson, D B; Farley, K A; Schmitz, B

    1998-11-01

    We have measured the helium abundance and isotopic composition of a suite of Lower Ordovician marine limestones and associated fossil meteorites from Kinnekulle, Sweden. Limestone 3He/4He ratios as high as 11.5 times the atmospheric value in fused samples and up to 23 times atmospheric in a single step-heat fraction indicate the presence of extraterrestrial helium, and demonstrate that at least a fraction of the extraterrestrial 3He carried by interplanetary dust particles must be retained against diffusive and diagenetic losses for up to 480 Ma. The carrier phase has not been identified but is not magnetic. Extrapolation of high-temperature 3He diffusivities in these sediments is consistent with strong retention of extraterrestrial 3He under ambient Earth-surface conditions. Combination of the observed helium concentrations with sedimentation rates estimated from conodont biostratigraphy suggest that the flux of extraterrestrial 3He in the Early Ordovician was about 0.5 x 10(-12) cm3 STP cm-2 ka-1, ignoring potential post-deposition helium loss. This value is indistinguishable from the average 3He flux estimated for the Cenozoic Era. In contrast, previous studies of fossil meteorites, Ir abundances, and Os isotopic ratios in the limestone suggest that the total accretion rate of extraterrestrial material during the studied interval was at least an order of magnitude higher than the Cenozoic average. This disparity may reflect significant post-depositional loss of 3He from IDPs within these old limestones; if so, the match between the Ordovician flux and the Cenozoic average would be fortuitous. Alternatively, the size distribution of infalling objects during the Early Ordovician may have been enriched only in extraterrestrial material too large to retain 3He during atmospheric entry heating (> approximately 30 micrometers). The fossil meteorites themselves also preserve extraterrestrial helium. Meteorite 3He concentrations of 2 to 9 x 10(-12) cm3 STP g-1 are

  2. Cretaceous planktic foraminiferal biostratigraphy of the Calera Limestone, Northern California, USA

    USGS Publications Warehouse

    Sliter, W.V.

    1999-01-01

    The Calera Limestone is the largest, most stratigraphically extensive limestone unit of oceanic character included in the Franciscan Complex of northern California. The aim of this paper is to place the Calera Limestone at its type locality (Rockaway Beach, Pacifica) in a high-resolution biostratigraphy utilizing planktic foraminifers studied in thin section. A section, about 110 m-thick, was measured from the middle thrust slice exposed by quarrying on the southwest side of Calera Hill at Pacifica Quarry. Lithologically, the section is divided in two units; a lower unit with 73 m of black to dark-grey limestone, black chert and tuff, and an upper unit with 36.8 m of light-grey limestone and medium-grey chert. Two prominent black-shale layers rich in organic carbon occur 11 m below the top of the lower black unit and at the boundary with overlying light-grey unit, yielding a total organic content (TOC) of 4.7% and 1.8% t.w., respectively. The fossiliferous Calera Limestone section measured at Pacifica Quarry, from the lower black shale, contains eleven zones and three subzones that span approximately 26 m.y. from the early Aptian to the late Cenomanian. The zones indentified range from the Globigerinelloides blowi Zone to the Dicarinella algeriana Subzone of the Rotalipora cushmani Zone. Within this biostratigraphic interval, the Ticinella bejaouaensis and Hedbergella planispira Zones at the Aptian/Albian boundary are missing as are the Rotalipora subticinensis Subzone of the Biticinella breggiensis Zone and the overlying Rotalipora ticinensis Zone in the late Albian owing both to low-angle thrust faulting and to unconformities. The abundance and preservation of planktic foraminifers are poor in the lower part and improve only within the upper G. algerianus Zone. The faunal relationship indicate that the lower black shale occurs in the upper part of the G. blowi Zone and correlates with the Selli Event recognized at global scale in the early Aptian. The upper black

  3. Beam injection into RHIC

    SciTech Connect

    Fischer, W.; Hahn, H.; MacKay, W.W.; Satogata, T.; Tsoupas, N.; Zhang, W.

    1997-07-01

    During the RHIC sextant test in January 1997 beam was injected into a sixth of one of the rings for the first time. The authors describe the injection zone and its bottlenecks. They report on the commissioning of the injection system, on beam based measurements of the kickers and the application program to steer the beam.

  4. Laboratory Investigations in Support of Carbon Dioxide-Limestone Sequestration in the Ocean

    SciTech Connect

    Dan Golomb; Eugene Barry; David Ryan; Stephen Pennell; Peter Swett; Huishan Duan; Michael Woods

    2006-04-01

    This semi-annual progress reports includes further findings on CO{sub 2}-in-Water emulsions stabilized by fine particles of limestone (CaCO{sub 3}). Specifically, here we report on the tests performed in the DOE National Energy Technology Laboratory High Pressure Water Tunnel Facility (HPWTF) using a Kenics-type static mixer for the formation of a CO{sub 2}-H{sub 2}O emulsion stabilized by fine particles of CaCO{sub 3}. The tested static mixer has an ID of 0.5 cm, length 23.5 cm, number of baffles 27. Under pressure, a slurry of CaCO{sub 3} particles (mean particle size 6 {micro}m) in reverse osmosis (RO) water and liquid CO{sub 2} were co-injected into the mixer. From the mixer, the resulting emulsion flowed into the HPWTF, which was filled with RO water kept at 6.8 MPa pressure and 4, 8 or 12 C. The emulsion plume was photographed by three video cameras through spy windows mounted on the wall of the HPWTF. The mixer produced an emulsion consisting of tiny CO{sub 2} droplets sheathed with a layer of CaCO{sub 3} particles dispersed in water. The sheathed droplets are called globules. The globules diameter was measured to be in the 300-500 {micro}m range. The globules were sinking in the HPWTF, indicating that they are heavier than the ambient water. The tests in the HPWTF confirmed that the Kenics-type static mixer is an efficient device for forming a CO{sub 2}-H{sub 2}O emulsion stabilized by fine particles of CaCO{sub 3}. The static mixer may prove to be a practical device for sequestering large quantities of CO{sub 2} in the deep ocean in the form of a CO{sub 2}-H{sub 2}O-CaCO{sub 3} emulsion. The static mixer can be mounted at the end of pipelines feeding the mixer. The static mixer has no moving parts. The pressure drop across the mixer that is necessary to sustain good mixing is created by the hydrostatic pressure of liquid CO{sub 2} and the slurry of CaCO{sub 3} in the pipes that feed the mixer. The tests in the HPWTF demonstrated that the emulsion plume is

  5. Strategies for safe injections.

    PubMed Central

    Battersby, A.; Feilden, R.; Stoeckel, P.; Da Silva, A.; Nelson, C.; Bass, A.

    1999-01-01

    In 1998, faced with growing international concern, WHO set out an approach for achieving injection safety that encompassed all elements from patients' expectations and doctors' prescribing habits to waste disposal. This article follows that lead and describes the implications of the approach for two injection technologies: sterilizable and disposable. It argues that focusing on any single technology diverts attention from the more fundamental need for health services to develop their own comprehensive strategies for safe injections. National health authorities will only be able to ensure that injections are administered safely if they take an approach that encompasses the whole system, and choose injection technologies that fit their circumstances. PMID:10680247

  6. Small polarons in dry DNA

    NASA Astrophysics Data System (ADS)

    Chacham, Helio; Alexandre, Simone S.; Soler, Jose M.; Artacho, Emilio

    2004-03-01

    The phenomenon of charge transport in DNA has been attracting attention of both biologists and physicists. From the biology side, there are evidences that charge injection can be associated to damage, mutation, and repair processes in DNA. From the physical sciences side, recent developments in nanotechnology now allow the measurement of currents through single DNA molecules in dried samples, which depict semiconductor behavior. Several mechanisms have been proposed for charge migration and transport in DNA. In that respect, detailed electrical transport measurements through DNA molecules containing identical base pairs (poly(dA)-poly(dT) and poly(dG)-poly(dC)) have been recently reported by Yoo et al [1]. These results fit extremely well a model in which the conduction is due to small polaron motion. In particular, these results indicate that the I-V characteristic of poly(dG)-poly(dC) DNA above 200 K is consistent with a small polaron hopping regime with an activation energy of 0.12 eV. In this work [2] we investigate the polaron formation in dry DNA by applying ab initio calculations to both neutral and charged fragments of dry poly(dG)-poly(dC). Our calculations show that the hole polaron in dry poly(dG)-poly(dC) DNA is a clear case of small polaron. This is verified by four basic properties: (i) the small variation of the polaron binding energy as a function of the DNA fragment size, for small fragment sizes, which is an indication of polaron localization; (ii) the fact that the width of the uppermost valence band is an order of magnitude smaller than the polaron binding energy; (iii) the explicit localization of the hole wavefunction for the largest considered fragment (four base pairs), indicated by the fact that about half of the norm of the hole is localized on a single guanine site; (iv) the localization of structural deformations at the nucleotides where the hole is concentrated. Our calculations also give a polaron binding energy of 0.30 eV. This allows

  7. Microstructural study of sulfate attack on ordinary and limestone Portland cements at ambient temperature

    SciTech Connect

    Irassar, E.F.; Bonavetti, V.L.; Gonzalez, M

    2003-01-01

    This paper presents an investigation on the mechanism of sulfate attack on Portland cements (PCs) containing limestone filler. It is based on the analysis of microstructure and composition of mortar specimens (ASTM C 1012) stored for 2 years in sodium sulfate solution (0.352 M). Microstructure was studied using quantitative X-ray diffraction (XRD) on samples taken from the surface to the core of the specimens. The profile of compounds formed by sulfate attack was determined millimeter by millimeter at 1 and 2 years. Results show that sulfate attack in mortars containing limestone filler is characterized by an inward movement of the reaction front leading first to the formation of ettringite, later to gypsum deposition, and finally to thaumasite formation when the decalcification of mortar leads to the breakdown of C-S-H.

  8. A Novel Treatment for Acid Mine Drainage Utilizing Reclaimed Limestone Residual

    SciTech Connect

    Horace K. Moo-Young; Charles E. Ochola

    2004-08-31

    The viability of utilizing Reclaimed Limestone Residual (RLR) to remediate Acid Mine Drainage (AMD) was investigated. Physical and chemical characterization of RLR showed that it is composed of various minerals that contain significant quantities of limestone or calcium bearing compounds that can be exploited for acid neutralization. Acid Neutralization Potential (ANP) test results showed that RLR has a neutralization potential of approximately 83% as calcium carbonate (CaCO{sub 3}). Neutralization tests with most of the heavy metals associated with AMD showed removal efficiencies of over 99%. An unexpected benefit of utilizing RLR was the removal of hexavalent chromium Cr (VI) from the aqueous phase. Due to an elevation in pH by RLR most AMD heavy metals are removed from solution by precipitation as their metal hydroxides. Cr (VI) however is not removed by pH elevation and therefore subsequent ongoing tests to elucidate the mechanism responsible for this reaction were conducted.

  9. Subsurface variation in the high-calcium dolbee Creek limestone in western Illinois

    NASA Astrophysics Data System (ADS)

    Cloos, M.; Baxter, J.

    1981-01-01

    High calcium limestone in the lower Burlington Quincy Beds', now assigned to the Dolbee Creek Member of the Burlington Limestone, was quarried and mined for over 100 years near Quincy in Adams County, Illinois. Mining was conducted primarily through adits in the bluffs of the Mississippi River. This report presents data on stratigraphic, lithologic, and chemical variations over a wide area of the shallow subsurface north and northeast of Quincy in central western Illinois, where the Dolbee Creek Member occurs at depths that are accessible to mining only by shafts or inclines. Our report is based on the study of diamond drill borings in Adams, Fulton, Hancock, Henderson, Knox, McDonough, and Warren Counties.

  10. Testing and commercialization of byproduct dibasic acids as buffer additives for limestone flue gas desulfurization systems

    SciTech Connect

    Chang, J.C.S.; Mobley, J.D.

    1983-10-01

    Pilot plant (0.1 MW) tests and utility boiler full scale demonstration (194 MW) of byproduct organic dibasic acids (DBA) as buffer additives to limestone scrubbers have shown performance improvements equivalent to those achieved by the addition of pure adipic acid. Both SO/sub 2/ removal efficiency and limestone utilization increased, and no significant operating problems were observed with three of the four DBA tested. Chemical and biological evaluations of scrubber samples taken during the DBA testing indicated no detectable toxicity or mutagenicity, and no significant environmental impact is expected as a result of DBA addition. Economic estimates indicate that substitution of DBA for pure adipic acid as a buffer additive will result in additive cost savings of 30% or greater.

  11. Paleokarst processes in the Eocene limestones of the Pyramids Plateau, Giza, Egypt

    NASA Astrophysics Data System (ADS)

    El Aref, M. M.; Refai, E.

    The Eocene limestones of the Pyramids plateau are characterized by landforms of stepped terraced escarpment and karst ridges with isolated hills. The carbonate country rocks are also dominated by minor surface, surface to subsurface and subsurface solution features associated with karst products. The systematic field observations eludicate the denudation trend of the minor solution features and suggest the origin of the regional landscapes. The lithologic and structural characters of the limestone country rocks comprise the main factors controlling the surface and subsurface karst evolution. The development of the karst features and the associated sediments in the study area provides information on the paleohydrolic, chemical and climatic environments involved in the origin of the karstification.

  12. Intermediate-scale sodium-concrete reaction tests with basalt and limestone concrete

    SciTech Connect

    Hassberger, J.A.; Muhlestein, L.D.

    1981-01-01

    Ten tests were performed to investigate the chemical reactions and rate and extent of attack between sodium and basalt and limestone concretes. Test temperatures ranged from 510 to 870/sup 0/C (950 to 1600/sup 0/F) and test times from 2 to 24 hours. Sodium hydroxide was added to some of the tests to assess the impact of a sodium hydroxide-aided reaction on the overall penetration characteristics. Data suggest that the sodium penetration of concrete surfaces is limited. Penetration of basalt concrete in the presence of sodium hydroxide is shown to be less severe than attack by the metallic sodium alone. Presence of sodium hydroxide changes the characteristics of sodium penetration of limestone concrete, but no major differences in bulk penetration were observed as compared to penetration by metallic sodium.

  13. Effect of particle size in a limestone-hydrochloric acid reaction system.

    PubMed

    Sun, Bo; Zhou, Qulan; Chen, Xi; Xu, Tongmo; Hui, Shien

    2010-07-15

    Experimental characterization of the wet flue gas desulfurization process is carried out using a model limestone-hydrochloric acid reaction system, with in-situ measurement of the dissolution rate and particle size distribution. The limestone source, initial particle size distribution, working temperature and pH value are varied in large ranges. The dissolution rate is found to be higher when the average particle size is smaller, the temperature is higher, or the pH is lower. An empirical equation is established to correlate the dissolution rate with the particle size and working conditions, which agrees well with measurements. The results may be useful for providing insights to improve the efficiency of the wet flue gas desulfurization process, as well as other solid particle-liquid solution reactions.

  14. Attenuation of stormwater contaminants from highway runoff within unsaturated limestone, Dade County, Florida

    USGS Publications Warehouse

    Waller, Bradley G.; Klein, Howard; Lefkoff, Lawrence J.

    1984-01-01

    Infiltration of stormwater in heavily urbanized parts of Dade County, Florida, is a prime source of recharge to the unconfined Biscayne aquifer, the sole source of drinking water for southeast Florida. Ponded stormwater at the test site contained greater concentrations of lead, zinc, manganese, nitrogen (except nitrate), and phosphorus than the water which percolated through the unsaturated limestone. Attenuation of some stormwater contaminants in the surface soils and limestone is indicated at the test site adjacent to a busy throughfare. Lead concentrations of 610 micrograms per kilogram and zinc concentrations of 91 micrograms per kilogram were found in the thin surface soils, nearly 20 times more than the concentrations of these metals at greater depth. In contrast, soil and rock sample at a control site remote from heavy traffic contained low concentrations of metals and showed little variation in concentration with depth. (USGS)

  15. Analysis of roof and pillar failure associated with weak floor at a limestone mine

    PubMed Central

    Murphy, Michael M.; Ellenberger, John L.; Esterhuizen, Gabriel S.; Miller, Tim

    2016-01-01

    A limestone mine in Ohio has had instability problems that have led to massive roof falls extending to the surface. This study focuses on the role that weak, moisture-sensitive floor has in the instability issues. Previous NIOSH research related to this subject did not include analysis for weak floor or weak bands and recommended that when such issues arise they should be investigated further using a more advanced analysis. Therefore, to further investigate the observed instability occurring on a large scale at the Ohio mine, FLAC3D numerical models were employed to demonstrate the effect that a weak floor has on roof and pillar stability. This case study will provide important information to limestone mine operators regarding the impact of weak floor causing the potential for roof collapse, pillar failure, and subsequent subsidence of the ground surface. PMID:27088041

  16. A Homoploid Hybrid Between Wild Vigna Species Found in a Limestone Karst

    PubMed Central

    Takahashi, Yu; Iseki, Kohtaro; Kitazawa, Kumiko; Muto, Chiaki; Somta, Prakit; Irie, Kenji; Naito, Ken; Tomooka, Norihiko

    2015-01-01

    Genus Vigna comprise several domesticated species including cowpea and mungbean, and diverse wild species. We found an introgressive hybrid population derived from two wild species, Vigna umbellata and Vigna exilis, in Ratchaburi district, Thailand. The hybrid was morphologically similar to V. umbellata but habituated in a limestone rock mountain, which is usually dominated by V. exilis. Analyzing simple sequence repeat loci indicated the hybrid has undergone at least one round of backcross by V. umbellata. We found the hybrid acquired vigorous growth from V. umbellata and drought tolerance plus early flowering from V. exilis, and thus has taken over some habitats of V. exilis in limestone karsts. Given the wide crossability of V. umbellata, the hybrid can be a valuable genetic resource to improve drought tolerance of some domesticated species. PMID:26648953

  17. Petrography study of two siliceous limestones submitted to alkali-silica reaction

    SciTech Connect

    Monnin, Y. . E-mail: monnin@ensm-douai.fr; Degrugilliers, P.; Bulteel, D.; Garcia-Diaz, E.

    2006-08-15

    This study presents the contribution of petrography to the comprehension of the alkali-silica reaction mechanism applied to two siliceous limestones. A petrography study was made on the two aggregates before reaction to define their relative proportions and types of reactive silica and to observe their distribution in the microstructure. Then a model reactor, constituted by the reactive siliceous limestone aggregate, portlandite and NaOH, was used to measure the swelling due to reaction of the silica with alkalis and the free expansion of the aggregates. The volume evolution between both aggregates was very different and could be explained by the preliminary petrographic study. It appears that the swelling of the aggregates is conditioned by the microstructure of the carbonated matrix, the quantity and the distribution of the reactive silica.

  18. Freeze drying method

    DOEpatents

    Coppa, Nicholas V.; Stewart, Paul; Renzi, Ernesto

    1999-01-01

    The present invention provides methods and apparatus for freeze drying in which a solution, which can be a radioactive salt dissolved within an acid, is frozen into a solid on vertical plates provided within a freeze drying chamber. The solid is sublimated into vapor and condensed in a cold condenser positioned above the freeze drying chamber and connected thereto by a conduit. The vertical positioning of the cold condenser relative to the freeze dryer helps to help prevent substances such as radioactive materials separated from the solution from contaminating the cold condenser. Additionally, the system can be charged with an inert gas to produce a down rush of gas into the freeze drying chamber to also help prevent such substances from contaminating the cold condenser.

  19. Freeze drying apparatus

    DOEpatents

    Coppa, Nicholas V.; Stewart, Paul; Renzi, Ernesto

    2001-01-01

    The present invention provides methods and apparatus for freeze drying in which a solution, which can be a radioactive salt dissolved within an acid, is frozen into a solid on vertical plates provided within a freeze drying chamber. The solid is sublimated into vapor and condensed in a cold condenser positioned above the freeze drying chamber and connected thereto by a conduit. The vertical positioning of the cold condenser relative to the freeze dryer helps to help prevent substances such as radioactive materials separated from the solution from contaminating the cold condenser. Additionally, the system can be charged with an inert gas to produce a down rush of gas into the freeze drying chamber to also help prevent such substances from contaminating the cold condenser.

  20. Importance of Radius of Influence and its Estimation in a Limestone Quarry

    NASA Astrophysics Data System (ADS)

    Soni, A. K.; Sahoo, L. K.; Ghosh, U. K.; Khond, M. V.

    2015-04-01

    Limestone mining at Lanjiberna limestone and dolomite quarry has created positive as well negative impacts on ground water. With further deepening of the mine, drawdown trend (negative effect) is observed and at the same time ground water recharge of the order of 4,527.48 m3/day, through mine pits (positive impact) is noticed. The aquifer present in the area is unconfined and mainly consists of weathered quartzite, phyllites, limestone and dolomite. To know the cumulative impact of mining on surroundings, the effective radius of influence (Re) for excavated mine area is calculated as 1,059 m. Here, it may be noted that three `concentric working pits' (Pit No. 2 & 6; Pit no 1 & 3 and Pit No 4 & 5) produces limestone at this mine and the pit-wise radius of influence (Ro) is estimated. Value of Ro for Pit-2 & 6 is 612.14 m; Pit-1 & 3 is 475 m and Pit-4 & 5 is 384.15 m. Its average i.e., Ro (for all three pits, cumulative) is estimated as 490 m. From this typical case study and estimation of Ro and Re values, it is concluded that the maximum and minimum value of overall impact/influence lies in between 0.49 and 1.05 km. These estimated values of `area of influence' are less compared to the whole mine lease area values. Local aquifer, which lies at shallower as well as at deeper depth had behaved consistently with respect to recharge and drawdown conditions. Thus, assessment of Ro and Re is extremely helpful for `integrated mine planning' to achieve targeted production, economically with minimum interruptions.

  1. Meteoric diagenesis, marine diagenesis, and microporosity in Pleistocene and Oligocene limestones, Enewetak Atoll, Marshall Islands

    NASA Astrophysics Data System (ADS)

    Saller, Arthur H.; Moore, Clyde H.

    1989-07-01

    Microporosity occurs in Pleistocene and Oligocene limestones cored on Enewetak Atoll. In cores of Pleistocene limestone (10-80 m deep), mi microporosity is present in aragonitic skeletal grains that underwent partial intrafabric dissolution (chalkification) leaving a porous meshwork of aragonite needles. Microporous aragonite is most abundant in 5-10 m thick intervals below zones of intense diagenesis associated with paleo-freshwater lenses. Extensive microporosity was apparently generated by slow intrafabric dissolution of aragonite in mixing zones below freshwater lenses. Microporous aragonite is an intermediate step in the calcitization or dissolution of aragonite. Most calcitized aragonite (neomorphic calcite) formed by precipitation of sparry calcite in (over) microporous aragonite. Aragonitic fossils were not converted to microporous, microcrystalline calcite. Therefore, data from the Pleistocene of Enewetak suggest that widespread, microporous, microcrystalline calcite does not form directly from pure aragonite, at least not in open meteoric systems or mixing zones. Microporous micrite occurs in Oligocene wackestones 930 m deep deposited in a slope environment. The microporous micrite is characterized by equant and prismatic crystals of low-magnesium calcite (LMC). Equant crystals are anhedral to euhedral and 2-10 μm in diameter. Prismatic calcite crystals are subhedral, 5-10 μm wide, and 20-50 μm long. Stable isotopic and trace element geochemistry suggest that microporous micrite formed by diagenetic alteration of high-magnesium calcite (HMC) micrite in deep seawater undersaturated with respect to HMC but supersaturated with respect to LMC (probably near the sediment-water interface). Mineralogy and crystal morphology of the microporous aragonite is very different from microporous shelf limestones in the Thamama Group (Cretaceous, Persian Gulf; see Moshier, 1989). Equant microcrystals of calcite in the Oligocene micrites are similar to those in

  2. Condition assessment of a highly porous limestone fortress: damage categories and structural integrity

    NASA Astrophysics Data System (ADS)

    Török, Ákos; Czinder, Balázs; Farkas, Orsolya; Görög, Péter; Kopecskó, Katalin; Lógó, János; Rozgonyi-Boissinot, Nikoletta; Vásárhelyi, Balázs

    2016-04-01

    An emblematic monument the Citadella fortress of Budapest has been studied in details to assess the condition of stone structure. The fortress is a large stone structure of 220 m in length and 60 m in width. The height of the porous limestone walls are in between 12-16 metres. The fortress was completed in 1854 but has been partly rebuilt due to changes in function and war related structural damages. The present paper provides an overview of the lithology, weathering forms and structural condition of the fortress related to a forthcoming restoration-reconstruction project. To assess the condition of stone both on site and laboratory analyses were performed. Lithological varieties were documented. Major identified lithotypes are porous oolitic limestone, less porous bioclastic limestone and fine grained highly porous limestone. To identify wet zones portable moisture meter was applied. Surface strength and weathering grade were also assessed using Schmidt hammer and Duroscop. Decay features were diagnosed and mapped. The most common forms are white weathering crusts, scaling and blistering of crusts as well as granular disintegration. Black weathering crusts were also recognized. Laboratory tests were focused on mechanical properties of stones and on mineralogical and chemical compositional analyses. Small samples of stone were collected and tested by optical microscopy, SEM-EDX, XRD and Thermogravimetric analyses. Laboratory analyses proved that the major salt responsible for the damage of external walls is gypsum, although significant amount of halite and hygroscopic salts were found both on the external walls and in the interior parts of the fortress. During structural analyses displacement of walls, tilting and major amount of cracks were recognized. Loss of material and subsidence also caused problems and at some places unstable wall sections were recognized.

  3. Changes in Zn speciation during soil formation from Zn-rich limestones

    NASA Astrophysics Data System (ADS)

    Jacquat, Olivier; Voegelin, Andreas; Juillot, Farid; Kretzschmar, Ruben

    2009-10-01

    In order to better understand the long-term speciation and fractionation of Zn in soils, we investigated three soils naturally enriched in Zn (237-864 mg/kg Zn) from the weathering of Zn-rich limestones (40-207 mg/kg Zn) using extended X-ray absorption fine structure (EXAFS) spectroscopy and sequential extractions. The analysis of bulk EXAFS spectra by linear combination fitting (LCF) indicated that Zn in the oolitic limestones was mainly present as Zn-containing calcite (at site Dornach), Zn-containing goethite (Gurnigel) and Zn-containing goethite and sphalerite (Liestal). Correspondingly, extraction of the powdered rocks with 1 M NH 4-acetate at pH 6.0 mobilized only minor fractions of Zn from the Gurnigel and Liestal limestones (<30%), but most Zn from the Dornach rock (81%). In the Dornach soil, part of the Zn released from the dissolving limestone was subsequently incorporated into pedogenic hydroxy-interlayered vermiculite (Zn-HIV, ˜30%) and Zn-containing kaolinite (˜30%) and adsorbed or complexed by soil organic and inorganic components (˜40%). The Gurnigel and Liestal soils contained substantial amounts of Zn-containing goethite (˜50%) stemming from the parent rock, smaller amounts (˜20%) of Zn-containing kaolinite (and possibly Zn-HIV), as well as adsorbed or complexed Zn-species (˜30%). In the soil from Liestal, sphalerite was only found in trace amounts, indicating its dissolution during soil formation. In sequential extractions, large percentages of Zn (˜55-85%) were extracted in recalcitrant extraction steps, confirming that Zn-HIV, Zn-containing kaolinite and Zn-containing goethite are highly resistant to weathering. These Zn-bearing phases thus represent long-term hosts for Zn in soils over thousands of years. The capability of these phases to immobilize Zn in heavily contaminated soils may however be limited by their uptake capacity (especially HIV and kaolinite) or their abundance in soil.

  4. Degradation of Mustard on Moist Sand, Asphalt, and Limestone Using 13C SSMAS NMR

    DTIC Science & Technology

    2006-12-01

    ASPHALT, AND LIMESTONE USING 13C SSMAS NMR Carol A. S. Brevett Carroll L. Cook Robert G. Nickol SA•C SAIC Abingdon, MD 21009 Kenneth B. Sumpter Monicia R...Cook, Carroll L.; Robert G. Nickol (SAIC);* Sumpter, Kenneth B.; Hall, Monicia R. (ECBC) Se. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING...James Savage, H. Dupont Durst , and Mark Brickhouse for programmatic support. 3 Blank CONTENTS 1. INTRODU CTION

  5. Selected data for wells and test holes used in structure-contour maps of the Inyan Kara Group, Minnekahta Limestone, Minnelusa Formation, Madison Limestone, and Deadwood Formation in the Black Hills area, South Dakota

    USGS Publications Warehouse

    Carter, J.M.

    1999-01-01

    This report presents selected data on wells and test holes that were used in the construction of structure-contour maps of selected formations that contain major aquifers in the Black Hills area of western South Dakota. Altitudes of the top of the Inyan Kara Group, Minnekahta Limestone, Minnelusa Formation, Madison Limestone, and Deadwood Formation are presented for the wells and test holes presented in this report.

  6. Acoustoconvection Drying of Meat

    NASA Astrophysics Data System (ADS)

    Zhilin, A. A.; Fedorov, A. V.

    2016-03-01

    The dynamics of moisture extraction from meat samples by the acoustoconvection and thermoconvection methods has been investigated. To describe the dynamics of moisture extraction from meat, we propose a simple relaxation model with a relaxation time of 8-10 min in satisfactorily describing experimental data on acoustoconvection drying of meat. For thermoconvection drying the relaxation time is thereby 30 and 45 min for the longitudinal and transverse positions of fibers, respectively.

  7. A study of the dry forest communities in the Dominican Republic.

    PubMed

    García-Fuentes, Antonio; Torres-Cordero, Juan A; Ruiz-Valenzuela, Luis; Lendínez-Barriga, María Lucía; Quesada-Rincón, Juan; Valle-Tendero, Francisco; Veloz, Alberto; León, Yolanda M; Salazar-Mendías, Carlos

    2015-03-01

    This paper is a floristic and phytosociological study of the dry forest communities of the Dominican Republic. A total of 69 relevés in dry forest biotopes were carried out. The samples were subsequently subjected to Detrended Correspondence Analysis for the determination and study of possible groupings. The study does not cover tree formations growing on serpentines, nor the so-called semideciduous forests, peculiar to areas with higher rainfall. A total of nine phytocoenoses were identified. The most significant results led to the description of six new phytosociological associations: Simaroubetum berteroani (thorny dry forest on coastal dunes), Phyllostylo rhamnoidis-Prosopidetum juliflorae (southern Dominican disturbed dry forest), Consoleo moniliformis-Camerarietum linearifoliae (dry forest on hard limestones), Lemaireocereo hystricis-Prosopidetum juliflorae (northern Dominican disturbed dry forest), Lycio americani-Prosopidetum juliflorae (disturbed dry forest on saline soils) and Guettardo ellipticae-Guapiretum discoloris (dry forest on flat-topped hillocks in Montecristi). This is an important step forward in the phytosociological and floristic studies of the Caribbean territories.

  8. Treatment of iron(II)-rich acid mine water with limestone and oxygen.

    PubMed

    Mohajane, G B; Maree, J P; Panichev, N

    2014-01-01

    The main components of acid mine water are free acid, sulphate, and Fe²⁺. Limestone is the most cost-effective alkali that can be used for neutralization. The purpose of this investigation was to identify conditions where Fe²⁺ is removed with limestone and simultaneously oxidized with oxygen to Fe³⁺, in a polyvinyl chloride pipe under pressure. Gypsum scaling is prevented by passing rubber balls through the pipe of the so-called Oxygen-Pipe-Neutralization (OPeN) process pilot plant. Two synthetic waters were treated: (A) acid mine water containing 123 mg L⁻¹ Fe²⁺ representing gold mine water, and (B) acid mine water containing 6,032 mg L⁻¹ Fe²⁺ representing coal mine water. Batch studies were carried out in a pipe reactor and showed that the rate of Fe²⁺ oxidation depended on the Fe²⁺ concentration, oxygen pressure, amount of recycled sludge, limestone dosage and the mixing rate. Continuous studies in an OPeN process pilot plant resulted in 100% removal of total acidity from synthetic coal mine water and a 98% removal from synthetic gold mine water. Fe²⁺ was removed completely as precipitated Fe(OH)₃ from both synthetic coal and gold mine water at around pH 7 at 200 and 100 kPa oxygen pressure, respectively.

  9. EPA's industry briefing on the organic-acid-enhanced limestone FGD process (July 1984): proceedings

    SciTech Connect

    Mobley, J.D.

    1985-03-01

    The proceedings document presentations made during an EPA-sponsored industry briefing which was held on July 19, 1984, in San Antonio, Texas. The briefing dealt with the status of EPA's research activities on the organic-acid-enhanced limestone flue gas desulfurization process. Subjects covered included: (1) technical and economic evaluation of organic acid addition to the San Miguel FGD system - results of parametric tests, (2) technical and economic evaluation of organic acid addition to the San Miguel FGD system - the utility's perspective, (3) results of the first two years of commercial operation of an organic-acid-enhanced FGD system, (4) economics of retrofitting Big Rivers Electric Corporation's lime based FGD system to organic-acid-enhanced limestone operations, and (5) an economic evaluation of limestone and lime flue gas desulfurization processes for new systems. The briefing provided users, architects and engineers, vendors, consultants, and government personnel with a comprehensive assessment of this innovative technology for controlling sulfur dioxide emissions. All five papers in this proceddings have been processed for inclusion in the Energy Data Base.

  10. Results of limestone clear liquor scrubbing tests at EPRI`s Environmental Control Technology Center (ECTC)

    SciTech Connect

    Hargrove, O.W. Jr.; Skarupa, R.C.; Wilhelm, J.H.

    1995-06-01

    In a continuing effort to offer lower cost SO{sub 2} control alternatives for its member utilities, EPRI has developed and tested a limestone clear liquor scrubbing using the 0.4-MW{sub e} mini-pilot FGD system at EPRI`s Environmental Control Technology Center. In the first-phase of testing, existing equipment was used to evaluate the feasibility of the process concept. Following the encouraging Phase I results, a pilot-scale sludge bed limestone reactor was designed and fabricated for a second-phase of testing. Tests have been conducted in both inhibited and forced oxidation modes. Variables investigated include: type of organic acid, buffer concentration, solid-phase residence time, pH, L/G, and chloride level. Results show that the clear liquor process can achieve SO{sub 2} removal and solids properties equivalent to or better than that of an enhanced slurry process without scale build-up. Preliminary economics indicate that the clear liquor gypsum process could reduce overall capital and operating expense by 5 to 10% relative to an organic acid-enhanced slurry process and by 15 to 20% relative to a conventional, unenhanced limestone process.

  11. Sea-level control of limestone composition: New data from quaternary carbonates in the Bahamas

    SciTech Connect

    Kindler, P. . Geology Dept.); Hearty, P.J. )

    1993-03-01

    Comprehensive petrographic analysis of limestone in the Bahamas reveals that their composition was ultimately controlled by climatic and sea-level changes during the Quaternary. These results demonstrate that facies analysis of limestone is not only useful for local and regional correlations, but also represents a powerful tool for unraveling the sea-level history of carbonate platforms. Ongoing stratigraphic research across the Bahamas leads to the recognition of nine platform-wide depositional units showing distinctive geomorphic, sedimentologic, petrologic and geochemical features. These units were deposited during major transgressive episodes from the middle Pleistocene to the late Holocene. They are bounded by glacial-age reddish paleosols. Petrographic variations between units do not occur randomly and are not uniquely determined by morphological controls (e.g. bank margin orientation). They are more likely related to climatic and eustatic changes. Oolitic/peloidal units were deposited during warm intervals when the Bahamian platform was totally submerged. Formation of skeletal units reflects cooler periods and partial flooding of the platform when carbonate production was limited to bank-fringing reefs. In conclusion, the limestone units exposed in the Bahamas are sensitive indicators of past sea-level fluctuations. Their composition is controlled by the degree of platform flooding and the rate of sea-level rise, while microfacies analysis has proven useful for paleoclimatic reconstruction.

  12. Sampling and analysis method for measuring airborne coal dust mass in mixtures with limestone (rock) dust

    PubMed Central

    Barone, T. L.; Patts, J. R.; Janisko, S. J.; Colinet, J. F.; Patts, L. D.; Beck, T. W.; Mischler, S. E.

    2016-01-01

    Airborne coal dust mass measurements in underground bituminous coal mines can be challenged by the presence of airborne limestone dust, which is an incombustible dust applied to prevent the propagation of dust explosions. To accurately measure the coal portion of this mixed airborne dust, the National Institute for Occupational Safety and Health (NIOSH) developed a sampling and analysis protocol that used a stainless steel cassette adapted with an isokinetic inlet and the low temperature ashing (LTA) analytical method. The Mine Safety and Health Administration (MSHA) routinely utilizes this LTA method to quantify the incombustible content of bulk dust samples collected from the roof, floor, and ribs of mining entries. The use of the stainless steel cassette with isokinetic inlet allowed NIOSH to adopt the LTA method for the analysis of airborne dust samples. Mixtures of known coal and limestone dust masses were prepared in the laboratory, loaded into the stainless steel cassettes, and analyzed to assess the accuracy of this method. Coal dust mass measurements differed from predicted values by an average of 0.5%, 0.2%, and 0.1% for samples containing 20%, 91%, and 95% limestone dust, respectively. The ability of this method to accurately quantify the laboratory samples confirmed the validity of this method and allowed NIOSH to successfully measure the coal fraction of airborne dust samples collected in an underground coal mine. PMID:26618374

  13. The sedimentological and diagenetic evolution of the Ratburi Limestone, Peninsular Thailand

    NASA Astrophysics Data System (ADS)

    Baird, Angus; Bosence, Dan

    The late Middle to early Late Permian Ratburi Limestone in Peninsular Thailand is a warm-water carbonate deposit formed in an extensive platform setting, suggesting that the Shan Thai craton occupied a subtropical-tropical position at this time. The distribution of facies, from peritidal, fenestral and algal laminated muds, to subtidal skeletal and ooid grainstones, bryozoa boundstones and carbonate slope deposits, is controlled by the platform topography, which is thought to have been controlled by extensional tectonics. Early diagenesis of the platform began with seawater-influenced dolomitisation, followed by uplift, producing karstification, in response to the Late Permian Indosinian orogeny. East dipping subduction of the Indian Ocean Plate resulted in granite magmatism in the peninsula during the Cretaceous. The effect on the Ratburi Limestone included neomorphism, dissolution, calcite cementation and dolomitisation. The petroleum potential of Ratburi Limestone comes from the extensive and long karstic history (Late Permian and Tertiary-present day) and the source potential of the widespread platform carbonate mudstone ( TOC <4.5%) .

  14. Multiple origins for zoned cathodoluminescent and noncathodoluminescent calcite cements in Pennsylvanian limestones

    SciTech Connect

    Goldstein, R.H.; Anderson, J.E.; Phares, R.A. )

    1991-03-01

    Noncathodoluminescent calcite containing brightly to moderately luminescent zones is a common early cement in limestones. Three such cements in Upper Pennsylvanian limestones from different areas were studied. All three units are overlain up-section by Permian evaporites and consist of carbonate-siliciclastic 'cyclothems' in which individual cycles were subject to subaerial exposure. With such similar settings, one might predict that petrographically similar calcite cements would have similar origins. In the Holder Formation (New Mexico), the zoned calcite predates compaction, and cross-cutting relationships with cycle-capping paleosols show that zoned cements precipitated during 15 events of subaerial exposure. Therefore, cements precipitated from freshwater during early and repeated subaerial exposure. For the Lansing-Kansas City groups in northwestern Kansas, the zoned calcite cements commonly are among the first precipitated but may postdate some compaction. All-liquid fluid inclusions indicated precipitation below about 50C, from brines of approximately 23 weight %. NaCl equivalent. The brines may have refluxed downward during deposition of Permian evaporites. A limestone of the Lansing-Kansas City groups of west-central Kansas contains early zoned calcite cement that predates compaction. The cement contains all-liquid fluid inclusions indicating precipitation below about 50C. The presence of nonluminescent calcite containing bright subzones is not indicative of a single diagenetic environment. Petrographically similar cements from similar settings may originate in markedly different diagenetic environments.

  15. [Sodium-enhanced limestone wet FGD in rotating-stream tray scrubber].

    PubMed

    Sun, Wenshou; Wu, Zhongbiao; Li, Yue; Tan, Tianen

    2002-09-01

    Adding sodium sulfate to limestone slurry can increase SO2 removal efficiency. In this paper, sodium-enhanced limestone flue gas desulfurization(FGD) tests were conducted in rotating-stream tray scrubber. Changes of SO2 removal efficiency and pH value with time were experimentally studied and, at different pH range, the dissolution rates of limestone etc. were analyzed. The effects of plate number on SO2 removal efficiency and pressure drop were investigated at temperature approximated to industrial operating value. The average plate efficiencies were calculated. According to the experimental results, increasing plate number could increase SO2 removal efficiency, but the average plate efficiency decreased. Under the experimental conditions, when the plate number was increased from 1 to 4, the removal efficiency was increased from 25.5% to 48.6% at the liquid-to-gas ratio of 4 L/m3, but the average plate efficiency was decreased from 25.5% to 15.3%. The equation of the relation between the average plate efficiency and plate number was obtained.

  16. Use Of limestone resources in flue-gas desulfurization power plants in the Ohio River Valley

    USGS Publications Warehouse

    Foose, M.P.; Barsotti, A.F.

    1999-01-01

    In 1994, more than 41 of the approximately 160 coal-fired, electrical- power plants within the six-state Ohio River Valley region used flue-gas desulfurization (FGD) units to desulfurize their emissions, an approximately 100% increase over the number of plants using FGD units in 1989. This increase represents a trend that may continue with greater efforts to meet Federal Clean Air Act standards. Abundant limestone resources exist in the Ohio River Valley and are accessed by approximately 975 quarries. However, only 35 of these are believed to have supplied limestone for FGD electrical generating facilities. The locations of these limestone suppliers do not show a simple spatial correlation with FGD facilities, and the closest quarries are not being used in most cases. Thus, reduction in transportation costs may be possible in some cases. Most waste generated by FGD electrical-generating plants is not recycled. However, many FGD sites are relatively close to gypsum wallboard producers that may be able to process some of their waste.

  17. Evaluation of the sulfur sorption properties of chemically improved limestones during fluidized-bed combustion

    SciTech Connect

    Grimm, U.

    1981-03-01

    A program was initiated in early 1980 at the Morgantown Energy Technology Center, Department of Energy, to evaluate the sulfur retention capability of a number of chemically improved limestones. These synthetic sorbents were developed by the University of Tennessee under an agreement with the Tennessee Valley Authority. Fredonia limestone and Shawnee hopper ash, in combination with a binder, are the main ingredients of the artificial sorbents. The manufacturing process of these pellets is described elsewhere. The effectiveness of the sorbents in sulfur emission controls and their calcium utilization potential were originally controlled by a rapid TG method displayed by the University of Tennessee. Performance data in real fluidizing combustion processes were missing. In a cooperative effort between the Morgantown Energy Technology Center and the Energy Research Division of TVA, an agreement was reached to test four new sorbents, a power station fly ash, and Fredonia limestone at the Morgantown 6-Inch Diameter AFBC Facility. The results generated in the fluidized-combustion test confirmed the findings by the University of Tennessee and the test program was determined to be highly successful. Details of the program as well as the results are presented in this report.

  18. Sampling and analysis method for measuring airborne coal dust mass in mixtures with limestone (rock) dust.

    PubMed

    Barone, T L; Patts, J R; Janisko, S J; Colinet, J F; Patts, L D; Beck, T W; Mischler, S E

    2016-01-01

    Airborne coal dust mass measurements in underground bituminous coal mines can be challenged by the presence of airborne limestone dust, which is an incombustible dust applied to prevent the propagation of dust explosions. To accurately measure the coal portion of this mixed airborne dust, the National Institute for Occupational Safety and Health (NIOSH) developed a sampling and analysis protocol that used a stainless steel cassette adapted with an isokinetic inlet and the low temperature ashing (LTA) analytical method. The Mine Safety and Health Administration (MSHA) routinely utilizes this LTA method to quantify the incombustible content of bulk dust samples collected from the roof, floor, and ribs of mining entries. The use of the stainless steel cassette with isokinetic inlet allowed NIOSH to adopt the LTA method for the analysis of airborne dust samples. Mixtures of known coal and limestone dust masses were prepared in the laboratory, loaded into the stainless steel cassettes, and analyzed to assess the accuracy of this method. Coal dust mass measurements differed from predicted values by an average of 0.5%, 0.2%, and 0.1% for samples containing 20%, 91%, and 95% limestone dust, respectively. The ability of this method to accurately quantify the laboratory samples confirmed the validity of this method and allowed NIOSH to successfully measure the coal fraction of airborne dust samples collected in an underground coal mine.

  19. Drying SDS-Polyacrylamide Gels.

    PubMed

    Sambrook, Joseph; Russell, David W

    2006-09-01

    INTRODUCTIONThis protocol describes a method for drying SDS-polyacrylamide gels. Gels containing proteins radiolabeled with (35)S-labeled amino acids must be dried before autoradiographic images can be obtained. Nonradioactive gels can also be preserved by drying.

  20. The Agoudal (High Atlas Mountains, Morocco) Shattered Limestone: Petrographical and Geochemical Studies and Additional Evidence of Impact

    NASA Astrophysics Data System (ADS)

    El Kerni, H.; Chennaoui Aoudjehane, H.; Marjanac, T.

    2016-08-01

    Agoudal impact structure shattered limestone and breccia are well studied and described using petrographical observations and geochemical analyses, and a new discovery of the magnesiwustite mineral as a further evidence of impact event.

  1. Fuel injection apparatus

    SciTech Connect

    Omori, T.; Sakakibara, S.; Kato, M.; Masuda, A.

    1986-06-10

    A fuel injection apparatus is described for supplying fuel from a fuel tank to at least one combustion chamber of an internal combustion engine, comprising: an injector housing defining therein a pressure cylinder bore, an injection cylinder bore and a timing cylinder bore connected in series with the pressure cylinder bore; a pressure plunger, fitted in the pressure cylinder bore and having one end defining, in the pressure cylinder bore, a pressure pump chamber communicating with the injection cylinder bore and the timing cylinder bore; first fuel supply means for supplying fuel from the fuel tank to the pressure pump chamber; pressurizing means for reciprocating the pressure plunger in the pressure cylinder bore in synchronism with the engine operation so as to pressurize fuel in the pressure pump chamber; an injection plunger, having a diameter smaller than the pressure plunger, fitted in the injection cylinder bore and having two ends defining, in the injection cylinder bore, an injection pump chamber and a first communicating chamber communicating with the pressure pump chamber; second fuel supply means for adjusting the quantity of the fuel from the fuel tank in accordance with engine operation conditions so as to supply the adjusted fuel quantity to the injection pump chamber; injection valve means for injecting the fuel into the fuel pump chamber toward a combustion chamber of the engine when the pressure in the pressure pump chamber is applied to the injection plunger through the first communicating chamber, and the fuel pressure in the injection pump chamber reaches a predetermined injection pressure.

  2. Acid mine drainage neutralization in a pilot sequencing batch reactor using limestone from a paper and pulp industry.

    PubMed

    Vadapalli, V R K; Zvimba, J N; Mathye, M; Fischer, H; Bologo, L

    2015-01-01

    This study investigated the implications of using two grades of limestone from a paper and pulp industry for neutralization of acid mine drainage (AMD) in a pilot sequencing batch reactor (SBR). In this regard, two grades of calcium carbonate were used to neutralize AMD in a SBR with a hydraulic retention time (including settling) of 100 min and a sludge retention time of 360 min, by simultaneously monitoring the Fe(II) removal kinetics and overall assessment of the AMD after treatment. The Fe(II) kinetics removal and overall AMD treatment were observed to be highly dependent on the limestone grade used, with Fe(II) completely removed to levels lower than 50 mg/L in cycle 1 after 30 min using high quality or pure paper and pulp limestone. On the contrary, the other grade limestone, namely waste limestone, could only achieve a similar Fe(II) removal efficiency after four cycles. It was also noticed that suspended solids concentration plays a significant role in Fe(II) removal kinetics. In this regard, using pure limestone from the paper and pulp industry will have advantages compared with waste limestone for AMD neutralization. It has significant process impacts for the SBR configuration as it allows one cycle treatment resulting in a significant reduction of the feed stock, with subsequent generation of less sludge during AMD neutralization. However, the use of waste calcium carbonate from the paper and pulp industry as a feed stock during AMD neutralization can achieve significant cost savings as it is cheaper than the pure limestone and can achieve the same removal efficiency after four cycles.

  3. Use of limestone karst forests by Bornean orangutans (Pongo pygmaeus morio) in the Sangkulirang peninsula, east Kalimantan, Indonesia.

    PubMed

    Marshall, Andrew J; Salas, Leonardo A; Stephens, Suzette; Engström, Linda; Meijaard, Erik; Stanley, Scott A

    2007-02-01

    The Indonesian province of East Kalimantan is home to some of the largest remaining contiguous tracts of lowland Dipterocarp forest on the island of Borneo. Nest surveys recently conducted in these forests indicated the presence of a substantial population of Eastern Bornean orangutans (Pongo pygmaeus morio) in the Berau and East Kutai regencies in the northern half of the province. The Sangkulirang Peninsula contains extensive limestone karst forests in close proximity to the lowland Dipterocarp forests inhabited by orangutans in these regencies. Orangutans have been sighted in these limestone karst forests, but the importance of this forest type for orangutans has been unclear. Therefore, we conducted 49 km of nest surveys in limestone karst forest to obtain the first quantitative estimates of orangutan densities in this habitat, and walked 28 km of surveys in nearby lowland Dipterocarp forests for comparison. We also gathered basic ecological data along our transects in an attempt to identify correlates of orangutan abundance across these habitat types. Undisturbed limestone karst forests showed the lowest orangutan densities (147 nests/km(2), 0.82 indiv/km(2)), disturbed limestone forests had intermediate densities (301 nests/km(2), 1.40 indiv/km(2)), and undisturbed lowland Dipterocarp forests contained the highest density (987 nests/km(2), 5.25 indiv/km(2)), significantly more than the undisturbed limestone karst forests. This difference was not correlated with variation in liana abundance, fig stem density, or stump density (an index of forest disturbance). Therefore, other factors, such as the relatively low tree species diversity of limestone karst forests, may explain why orangutans appear to avoid these areas. We conclude that limestone karst forests are of low relevance for safeguarding the future of orangutans in East Kalimantan.

  4. Geologic framework and hydrogeologic characteristics of the Glen Rose limestone, Camp Stanley Storage Activity, Bexar County, Texas

    USGS Publications Warehouse

    Clark, Allan K.

    2004-01-01

    The Trinity aquifer is a regional water source in the Hill Country of south-central Texas that supplies water for agriculture, commercial, domestic, and stock purposes. Rocks of the Glen Rose Limestone, which compose the upper zone and upper part of the middle zone of the Trinity aquifer, crop out at the Camp Stanley Storage Activity (CSSA), a U.S. Army weapons and munitions supply, maintenance, and storage facility in northern Bexar County (San Antonio area) (fig. 1). On its northeastern, eastern, and southern boundaries, the CSSA abuts the Camp Bullis Training Site, a U.S. Army field training site for military and Federal government agencies. During 2003, the U.S. Geological Survey (USGS), in cooperation with the U.S. Army, studied the outcropping Glen Rose Limestone at the CSSA and immediately adjacent area (Camp Stanley study area, fig. 1) to identify and map the hydrogeologic subdivisions and faults of the Glen Rose Limestone at the facility. The results of the study are intended to help resource managers improve their understanding of the distribution of porosity and permeability of the outcropping rocks, and thus the conditions for recharge and the potential for contaminants to enter the Glen Rose Limestone. This study followed a similar study done by the USGS at Camp Bullis (Clark, 2003). The purpose of this report is to present the geologic framework and hydrogeologic characteristics of the Glen Rose Limestone in the study area. The hydrogeologic nomenclature follows that introduced by Clark (2003) for the outcropping Glen Rose Limestone at Camp Bullis in which the upper member of the Glen Rose Limestone (hereinafter, upper Glen Rose Limestone), which is coincident with the upper zone of the Trinity aquifer, is divided into five intervals on the basis of observed lithologic and hydrogeologic properties. An outcrop map, two generalized sections, related illustrations, and a table summarize the description of the framework and distribution of characteristics.

  5. The microbial nature of laminated limestones: Lessons from the Upper Aptian, Araripe Basin, Brazil

    NASA Astrophysics Data System (ADS)

    Catto, Bruno; Jahnert, Ricardo Jorge; Warren, Lucas Verissimo; Varejao, Filipe Giovanini; Assine, Mario Luis

    2016-07-01

    The Araripe Basin, located in northeastern Brazil, originated during the Gondwana continental break-up responsible for the opening of the South Atlantic during the Early Cretaceous. In the Araripe Basin, the post-rift Aptian sequence corresponds to the Santana Group, which is composed, in upward succession, of mostly clastic continental and rare carbonate layers of the Barbalha, Crato, Ipubi and Romualdo Formations. The laminated limestones of the Crato Formation were deposited in a lacustrine environment preceding the deposition of the Ipubi Formation evaporites. They are age-equivalent to the limestones of the pre-salt interval of the east coast of Brazil, which contains large petroleum reserves. The excellent preservation of its macrofossils has made the Crato Formation known worldwide as a Fossil Lagerstätte. The limestones are macroscopically homogeneous, and their deposition has been previously attributed to chemical precipitation. Although the carbonate laminites are macroscopically undifferentiated, mineralogical variations, microscopic texture and distinctive biotic aspects supported the characterization of four microfacies: planar laminated, crustiform, nodular and rhythmic. The microfacies analysis indicated a strong and pervasive biological activity in the Crato limestone morphogenesis. Organominerals precipitated by the metabolic action of cyanobacteria and/or sulfate-reducing bacteria and methanogenic-oxidizing archea are represented by calcite and pyrite. Calcified coccoid and filaments are common, furthermore, the presence of calcified biofilms composed of exopolymeric substances (EPS) is ubiquitous. The presence of amorphous organic matter (AOM) and gypsum, particularly in the rhythmic microfacies, indicates anoxic/dysoxic conditions and stressful environments during periods of drought and low lake levels which favored the development and preservation of microbial biofilms. Phytoclasts and miospores when present in the succession indicate an

  6. Epidural injections for back pain

    MedlinePlus

    ESI; Spinal injection for back pain; Back pain injection; Steroid injection - epidural; Steroid injection - back ... pillow under your stomach. If this position causes pain, you either sit up or lie on your ...

  7. Characterization of pore structure and strain localization in Majella limestone by X-ray computed tomography and digital image correlation

    NASA Astrophysics Data System (ADS)

    Ji, Yuntao; Hall, Stephen A.; Baud, Patrick; Wong, Teng-fong

    2015-02-01

    Standard techniques for computed tomography imaging are not directly applicable to a carbonate rock because of the geometric complexity of its pore space. In this study, we first characterized the pore structure in Majella limestone with 30 per cent porosity. Microtomography data acquired on this rock was partitioned into three distinct domains: macropores, solid grains, and an intermediate domain made up of voxels of solid embedded with micropores below the resolution. A morphological analysis of the microtomography images shows that in Majella limestone both the solid and intermediate domains are interconnected in a manner similar to that reported previously in a less porous limestone. We however show that the macroporosity in Majella limestone is fundamentally different, in that it has a percolative backbone which may contribute significantly to its permeability. We then applied for the first time 3-D-volumetric digital image correlation (DIC) to characterize the mode of mechanical failure in this limestone. Samples were triaxially deformed over a wide range of confining pressures. Tomography imaging was performed on these samples before and after deformation. Inelastic compaction was observed at all tested pressures associated with both brittle and ductile behaviors. Our DIC analysis reveals the structure of compacting shear bands in Majella limestone deformed in the transitional regime. It also indicates an increase of geometric complexity with increasing confinement-from a planar shear band, to a curvilinear band, and ultimately to a diffuse multiplicity of bands, before shear localization is inhibited as the failure mode completes the transition to delocalized cataclastic flow.

  8. Injection-water quality

    SciTech Connect

    Patton, C.C. )

    1990-10-01

    Ideally, injection water should enter the reservoir free of suspended solids or oil. It should also be compatible with the reservoir rock and fluids and would be sterile and nonscaling. This paper discusses how the objective of any water-injection operation is to inject water into the reservoir rock without plugging or permeability reduction from particulates, dispersed oil, scale formation, bacterial growth, or clay swelling. In addition, souring of sweet reservoirs by sulfate-reducing bacteria should be prevented if possible.

  9. [Stability of liensinine injection].

    PubMed

    Hu, X M; Zhou, B H; Luo, S D

    1993-06-01

    The stability of liensinine injection was studied by accelarating test with classical isothermal method. Results of the study showed that the decomposition of the injection was found to be a first-order reaction. The activation energy was 75030 J.mol-1. The shelf life at 10 degrees C and 25 degrees C was predicted to be about 15 months and 3 months respectively. This experiment provides a reference for the storage of the injection.

  10. Duct injection technology prototype development

    SciTech Connect

    Harper, S.L. . Research and Development Div.)

    1991-08-01

    This report describes a test program conducted to determine the corrosion rate of materials in the dry scrubber or duct injection systems. Four materials were evaluated: 1010 carbon steel, Corten, 317SS and Hastelloy C-276. The results show that acidic conditions result in higher corrosion rates than alkaline conditions for all the materials. The carbon steel, Corten and stainless steel show moderate to heavy pitting attack in the acidic environment. For the alkaline conditions, the corrosion rates of carbon steel and Corten were higher than the stainless steel or Hastelloy C-276. Also, the corrosion rate of abraded specimens were four time those of unabraded specimens in the flue gas. It is probable that areas of wall-wetting and plugging in the duct injection process will exhibit high rates of corrosion for the carbon steel, Corten, and stainless steel materials. General corrosion and pitting corrosion will predominate. Additionally, abraded duct areas will corrode at a significantly higher rate than unabraded duct materials. 6 refs., 11 figs., 7 tabs.

  11. Trepostome and cystoporate bryozoans from the Lexington Limestone and the Clays Ferry Formation (Middle and Upper Ordovician) of Kentucky

    USGS Publications Warehouse

    Karklins, O.L.

    1984-01-01

    The Lexington Limestone and the Clays Ferry Formation of Kentucky contain an abundant and diversified fossil invertebrate fauna. This report is concerned with the trepostome and cystoporate bryozoans that constitute a major part of that fauna. The Lexington Limestone, largely a biofragmental fossiliferous limestone, rests disconformably on the Tyrone Limestone (Middle Ordovician). The Clays Ferry Formation consists of approximately equal amounts of biofragmentallimestone and shale, and it overlies conformably, or intertongues with, the upper part of the Lexington Limestone. The Clays Ferry Formation is overlain by the Garrard Siltstone (Upper Ordovician) in central Kentucky and intertongues with the Kope Formation (Upper Ordovician) in northern Kentucky. The MiddleUpper Ordovician boundary falls within the upper part of the Lexington Limestone and laterally equivalent strata of the Clays Ferry Formation. The Lexington Limestone has been divided into 12 members, consisting of calcarenites, calcisiltites, calcilutites, nodular limestones, and shales in various amounts, that intertongue complexly. Because of the great abundance of bryozoans this study is generally limited to bryozoans recovered from, in ascending order, the Grier Limestone Member, the Perryville Limestone Member, the Brannon Member, the Tanglewood Limestone Member, and the Millersburg Member of the Lexington Limestone and from the Clays Ferry Formation and its Point Pleasant Tongue. The trepostome and cystoporate bryozoans discussed are referred to 36 species belonging to 22 genera. The trepostome component includes 29 species belonging to 16 genera: Amplexopora, Atactoporella, Balticopora, Batostoma, Cyphotrypa, Dekayia, Eridotrypa, Hetero-_ trypa, Homotrypa, Homotrypella, Mesotrypa, Parvohallopora, Peronopora, Prasopora, Stigmatella, and Tarphophragma, a new genus. Five of the trepostome species are new: Balticopora arcuatilis, Cyphotrypa switzeriensis, Dekayia epetrima, Eridotrypa sadievillensis

  12. Botulinum toxin injection - larynx

    MedlinePlus

    Injection laryngoplasty; Botox-larynx: spasmodic dysphonia-BTX; Essential voice tremor (EVT)-btx; Glottic insufficiency; Percutaneous electromyography-guided botulinum toxin treatment; Percutaneous indirect laryngoscopy- ...

  13. Underground Injection Control (UIC)

    EPA Pesticide Factsheets

    Provide information on: individual injection well classes; regulations specific to each well class; technical guidance; compliance assistance; federal, state, and tribal/territory roles and responsibilities.

  14. Piezoelectric Injection Systems

    NASA Astrophysics Data System (ADS)

    Mock, R.; Lubitz, K.

    The origin of direct injection can be doubtlessly attributed to Rudolf Diesel who used air assisted injection for fuel atomisation in his first self-ignition engine. Although it became apparent already at that time that direct injection leads to reduced specific fuel consumption compared to other methods of fuel injection, it was not used in passenger cars for the moment because of its disadvantageous noise generation as the requirements with regard to comfort were seen as more important than a reduced specific consumption.

  15. Ixeridium calcicola (Compositae), a new limestone endemic from Taiwan, with notes on its atypical basic chromosome number, phylogenetic affinities, and a limestone refugium hypothesis.

    PubMed

    Nakamura, Koh; Chung, Shih-Wen; Kono, Yoshiko; Ho, Meng-Jung; Hsu, Tian-Chuan; Peng, Ching-I

    2014-01-01

    A new species Ixeridium calcicola (Compositae) endemic to middle altitude (ca 1,000-2,000 m asl) limestone mountains of eastcentral Taiwan is described based on morphological and chromosome cytological observations and molecular phylogenetic analyses. Ixeridium calcicola resembles Ixeridium transnokoense, endemic to upper montane and alpine ranges (2,600-3,500 m asl) of Taiwan, in the dwarf habit, but differs in the oblong to lanceolate leaf blades (vs. linear to linear-lanceolate), the presence of mucronulate teeth on the leaf margin and petiole (vs. smooth to very sparse), the dark purple lower leaf surface (vs. greenish), the capitulum with 10 to 12 florets (vs. 5 to 7) and 8 to 10 inner phyllaries (vs. 5, rarely to 7). The basic chromosome number in Ixeridium was known as X = 7. However, the new species has a basic chromosome number of X = 8, as recorded also in the closely related Ixeris. Molecular phylogenetic analyses with the expanded sampling of Ixeridium and Ixeris including both type species supported the monophyly of each of the genera and the placement of the new species in Ixeridium. The result of the phylogenetic analyses and detailed observation of the chromosome morphology revealed that X = 8 in Ixeridium calcicola is derived from centric fission in an ancestral karyomorphotype with X = 7 in Ixeridium. Ixeridium calcicola and Ixeridium transnokoense formed a Taiwan endemic lineage and their estimated divergence time was in the middle Pleistocene. Their common ancestral lineage may have experienced altitudinal distribution shifts in response to glacial-interglacial temperature fluctuation, and a lineage which had not retreated to alpine ranges in an interglacial period likely survived in a limestone refugium, where ordinary plant species did not grow, leading to allopatric speciation.

  16. Ixeridium calcicola (Compositae), a New Limestone Endemic from Taiwan, with Notes on Its Atypical Basic Chromosome Number, Phylogenetic Affinities, and a Limestone Refugium Hypothesis

    PubMed Central

    Kono, Yoshiko; Ho, Meng-Jung; Hsu, Tian-Chuan; Peng, Ching-I

    2014-01-01

    A new species Ixeridium calcicola (Compositae) endemic to middle altitude (ca 1,000–2,000 m asl) limestone mountains of eastcentral Taiwan is described based on morphological and chromosome cytological observations and molecular phylogenetic analyses. Ixeridium calcicola resembles Ixeridium transnokoense, endemic to upper montane and alpine ranges (2,600–3,500 m asl) of Taiwan, in the dwarf habit, but differs in the oblong to lanceolate leaf blades (vs. linear to linear-lanceolate), the presence of mucronulate teeth on the leaf margin and petiole (vs. smooth to very sparse), the dark purple lower leaf surface (vs. greenish), the capitulum with 10 to 12 florets (vs. 5 to 7) and 8 to 10 inner phyllaries (vs. 5, rarely to 7). The basic chromosome number in Ixeridium was known as X = 7. However, the new species has a basic chromosome number of X = 8, as recorded also in the closely related Ixeris. Molecular phylogenetic analyses with the expanded sampling of Ixeridium and Ixeris including both type species supported the monophyly of each of the genera and the placement of the new species in Ixeridium. The result of the phylogenetic analyses and detailed observation of the chromosome morphology revealed that X = 8 in Ixeridium calcicola is derived from centric fission in an ancestral karyomorphotype with X = 7 in Ixeridium. Ixeridium calcicola and Ixeridium transnokoense formed a Taiwan endemic lineage and their estimated divergence time was in the middle Pleistocene. Their common ancestral lineage may have experienced altitudinal distribution shifts in response to glacial-interglacial temperature fluctuation, and a lineage which had not retreated to alpine ranges in an interglacial period likely survived in a limestone refugium, where ordinary plant species did not grow, leading to allopatric speciation. PMID:25295587

  17. Tracers in rainfall simulation experiments to study the onset of the wet season in Eastern Mediterranean limestone environments

    NASA Astrophysics Data System (ADS)

    Lange, Jens

    2010-05-01

    The eastern Mediterranean rainfall regime is characterized by dry and hot summers and rainy cold winters. In this climate rocky limestone environments are regarded as major recharge zones due to (a) intensively enlarged fissures by solution weathering and (b) sparse vegetation and shallow soils which limit evapotranspiration losses. However, relatively little is known on hydrological processes during high magnitude rainstorms, which, at the beginning of the rainy season, may occur on both dry and wet soils. These conditions were investigated by a series of sprinkling experiments during two successive days. Rainfall was applied on large plots (143 and 180 m2) to include the variety of different terrain elements (rocky outcrops, bare soil, different vegetation). Sprinkling units were located at each corner of the plot and supplemented by additional ones to balance wind drift. This sprinkling set-up did not guarantee a uniform distribution of applied rainfall, as overlap of sprinkling areas could not be prevented. To assess the spatial rainfall distribution, a large number of totalizers was necessary. During two days of sprinkling these totalizers were regularly measured and spatially interpolated across the plot. The temporal rainfall distribution, a series of two high intensity storms on dry and wet soil, was observed by a tipping bucket raingauge. Tracers were added to the sprinkling water to obtain additional process insights. By end member mixing analysis the contribution of different water types (pre-sprinkling, first day, second day) could be quantified. The first plot was located on a steep rocky hillslope. Significantly different concentration of chloride, nitrate and sulfate in the sprinkling waters helped to identify first day's water in second day's runoff. Surface runoff was a combination of infiltration excess runoff from rocky portions of the plot and saturation excess runoff from areas covered by soil. Soil saturation was accelerated by lateral runoff

  18. Trigger Point Dry Needling.

    PubMed

    2017-03-01

    Increasingly, physical therapists in the United States and throughout the world are using dry needling to treat musculoskeletal pain, even though this treatment has been a controversial addition to practice. To better generalize to physical therapy practice the findings about dry needling thus far, the authors of a study published in the March 2017 issue of JOSPT identified the need for a systematic review examining the effectiveness of dry needling performed by physical therapists on people with musculoskeletal pain. Their review offers a meta-analysis of data from several included studies and assesses the evidence for risks of bias. J Orthop Sports Phys Ther 2017;47(3):150. doi:10.2519/jospt.2017.0502.

  19. Magnetically responsive dry fluids

    NASA Astrophysics Data System (ADS)

    Sousa, Filipa L.; Bustamante, Rodney; Millán, Angel; Palacio, Fernando; Trindade, Tito; Silva, Nuno J. O.

    2013-07-01

    Ferrofluids and dry magnetic particles are two separate classes of magnetic materials with specific niche applications, mainly due to their distinct viscosity and interparticle distances. For practical applications, the stability of these two properties is highly desirable but hard to achieve. Conceptually, a possible solution to this problem would be encapsulating the magnetic particles but keeping them free to rotate inside a capsule with constant interparticle distances and thus shielded from changes in the viscosity of the surrounding media. Here we present an example of such materials by the encapsulation of magnetic ferrofluids into highly hydrophobic silica, leading to the formation of dry ferrofluids, i.e., a material behaving macroscopically as a dry powder but locally as a ferrofluid where magnetic nanoparticles are free to rotate in the liquid.Ferrofluids and dry magnetic particles are two separate classes of magnetic materials with specific niche applications, mainly due to their distinct viscosity and interparticle distances. For practical applications, the stability of these two properties is highly desirable but hard to achieve. Conceptually, a possible solution to this problem would be encapsulating the magnetic particles but keeping them free to rotate inside a capsule with constant interparticle distances and thus shielded from changes in the viscosity of the surrounding media. Here we present an example of such materials by the encapsulation of magnetic ferrofluids into highly hydrophobic silica, leading to the formation of dry ferrofluids, i.e., a material behaving macroscopically as a dry powder but locally as a ferrofluid where magnetic nanoparticles are free to rotate in the liquid. Electronic supplementary information (ESI) available. See DOI: 10.1039/c3nr01784b

  20. Integrated dry NO sub x /SO sub 2 emissions control system

    SciTech Connect

    Not Available

    1992-02-15

    The DOE Cooperative Agreement No. DE-FC22-91PC90550 dated March 11, 1991, Public Service Company of Colorado has prepared the following quarterly report for Phases I, IIA, and IIB of the Integrated Dry NO{sub x}SO{sub 2} Emissions Control System Project. This project includes low NO{sub x} burners with NO{sub x} ports (post firing air injection), humidification and dry sorbent injection.