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Induced biochemical interactions in immature and biodegraded heavy crude oils

Description: Studies in which selective chemical markers have been used to explore the mechanisms by which biocatalysts interact with heavy crude oils have shown that the biochemical reactions follow distinct trends. The term biocatalyst refers to a group of extremophilic microorganisms which, under the experimental conditions used, interact with heavy crude oils to (1) cause a redistribution of hydrocarbons, (2) cause chemical changes in oil fractions containing sulfur compounds and lower the sulfur content, (3) decrease organic nitrogen content, and (4) decrease the concentration of trace metals. Current data indicate that the overall effect is due to simultaneous reactions yielding products with relatively higher concentration of saturates and lower concentrations of aromatics and resins. The compositional changes depend on the microbial species and the chemistry of the crudes. Economic analysis of a potential technology based on the available data indicate that such a technology, used in a pre-refinery mode, may be cost efficient and promising. In the present paper, the background of oil biocatalysis and some recent results will be discussed.
Date: November 1, 1998
Creator: Premuzic, E.T.; Lin, M.S.; Bohenek, M.; Joshi-Tope, G.; Shelenkova, L. & Zhou, W.M.
Partner: UNT Libraries Government Documents Department

Induced biochemical interactions in crude oils

Description: In the evolution of oil from sedimentary to reservoir conditions, the hydrogen to carbon ratios decrease while the oxygen, nitrogen, and sulfur to carbon ratios increase. During this process, the oils become heavier and richer in asphaltenes. In terms of chemical composition, the oils become enriched in resins, asphaltenes, and polar compounds containing the heteroatoms and metals. Over the geological periods of time, the chemical and physical changes have been brought about by chemical, biological (biochemical) and physical (temperature and pressure) means as well as by the catalytic effects of the sedimentary matrices, migration, flooding, and other physical processes. Therefore, different types of oils are the end products of a given set of such interactions which were brought about by multiple and simultaneous physicochemical processes involving electron transfer, free radical, and chemical reactions. A biocatalyst introduced into a reaction mixture of the type produced by such reactions will seek available chemical reaction sites and react at the most favorable ones. The rates and the chemical pathways by which the biocatalytic reactions will proceed will depend on the oil type and the biocatalyst(s). Some of the possible reaction pathways that may occur in such complex mixtures are discussed.
Date: August 1, 1996
Creator: Premuzic, E.T. & Lin, M.S.
Partner: UNT Libraries Government Documents Department

Determination of labile copper, cobalt, and chromium in textile mill wastewater

Description: Copper, chromium, and cobalt species present in filtered wastewater effluent were separated by cation exchange and reverse phase chromatography. Three sample fractions were obtained: one containing metal cations (i.e., trivalent Cr, divalent Cu, and divalent Co), one containing organic species (including metallized dyes), and one containing other unretained species. The metal content of each fraction was determined by inductively coupled plasma atomic emission spectroscopy (ICP-AES). The sum of the corrected data was compared to the metal content of a filtered effluent aliquot digested totally with fuming sulfuric acid. Other aliquots of the filtered effluent were spiked with the metals of interest and digested to confirm chemical yield and accuracy. Method detection limits were consistently below 20 {mu}g L{sup -1} for Cu, 30 {mu}g L{sup -1} for Co, and 10 {mu}g L{sup -1} for Cr. Spike recoveries for undifferentiated Cu and Cr were statistically indistinguishable from unity; although Co spike recoveries were slightly low ({approximately}95%), its chemical yield was 98%. Copper retention on the sodium sulfonate cation exchange resin was closely correlated with the [EDTA]/[Cu] ratio, suggesting that metals retained upon the cation exchange column were assignable to labile metal species; however, mass balances for all three elements, though reasonable ({approximately}90%), were significantly different from unity. Mechanical factors may have contributed to the material loss, but other data suggest that some metal species reacted irreversibly with the reverse phase column. 3 refs., 2 figs., 4 tabs.
Date: January 1, 1997
Creator: Crain, J.S.; Essling, A.M. & Kiely, J.T.
Partner: UNT Libraries Government Documents Department

Economic feasibility of biochemical processes for the upgrading of crudes and the removal of sulfur, nitrogen, and trace metals from crude oil -- Benchmark cost establishment of biochemical processes on the basis of conventional downstream technologies. Final report FY95

Description: During the past several years, a considerable amount of work has been carried out showing that microbially enhanced oil recovery (MEOR) is promising and the resulting biotechnology may be deliverable. At Brookhaven National Laboratory (BNL), systematic studies have been conducted which dealt with the effects of thermophilic and thermoadapted bacteria on the chemical and physical properties of selected types of crude oils at elevated temperatures and pressures. Current studies indicate that during the biotreatment several chemical and physical properties of crude oils are affected. The oils are (1) emulsified; (2) acidified; (3) there is a qualitative and quantitative change in light and heavy fractions of the crudes; (4) there are chemical changes in fractions containing sulfur compounds; (5) there is an apparent reduction in the concentration of trace metals; and (6) the qualitative and quantitative changes appear to be microbial species dependent; and (7) there is a distinction between biodegraded and biotreated oils. The downstream biotechnological crude oil processing research performed thus far is of laboratory scale and has focused on demonstrating the technical feasibility of downstream processing with different types of biocatalysts under a variety of processing conditions. Quantitative economic analysis is the topic of the present project which investigates the economic feasibility of the various biochemical downstream processes which hold promise in upgrading of heavy crudes, such as those found in California, e.g., Monterey-type, Midway Sunset, Honda crudes, and others.
Date: August 1, 1996
Creator: Premuzic, E.T.
Partner: UNT Libraries Government Documents Department

Characterizing the dealumination of environmentally relevant zeolites using IR, NMR and neutron diffraction techniques

Description: Results of characterization studies monitoring the sequential chemical bond breaking events, local site symmetry, and long range structural modifications of specific zeolites (H-ZSM-5, TS-1) during hydrothermal treatment of these catalyst materials are described. These characterization techniques include infrared spectroscopy of selected probe molecules, magic angle spinning NMR spectroscopy, and powder neutron diffraction. Information regarding selected examples from each of these techniques is presented and the inherent strengths of each is discussed. The experimental insight into the chemical and structural modifications of high surface area microporous catalyst materials as a function of deactivation conditions (hydrothermal conditioning) is highlighted.
Date: July 1, 1997
Creator: Paffett, M.T.; Szanyi, J.; Jacubinas, R.M.; Ott, K.C.; VonDreele, R.; Hughes, C.D. et al.
Partner: UNT Libraries Government Documents Department

Removal action work plan for the YS-860 Firing Ranges, Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

Description: The US Department of Energy is conducting environmental restoration activities at the Y-12 Plant in Oak Ridge, Tennessee. As part of these efforts, a removal action is planned for the former YS-860 Firing Ranges as described in the Action Memorandum for the project. This removal action work plan (RmAWP) is focused on the former YS-860 Firing Ranges, located outside the primary fenceline at the eastern end of the plant. This RmAWP defines the technical approach, procedures, and requirements for the removal of lead-contaminated soil and site restoration of the former YS-860 Firing Ranges at the Y-12 Plant. This RmAWP describes excavation, verification/confirmatory sampling, and reporting requirements for the project. Lower tier plans associated with the RmAWP, which are submitted as separate stand-alone documents, include a field sampling and analysis plan, a health and safety plan, a quality assurance project plan, a waste management plan, a data management implementation plan, and a best management practices plan. A site evaluation of the YS-86O Firing Ranges conducted in 1996 by Lockheed Martin Energy Systems, Inc., determined that elevated lead levels were present in the Firing Ranges target berm soils. The results of this sampling event form the basis for the removal action recommendation as described in the Action Memorandum for this project. This RmAWP contains a brief history and description of the Former YS-860 Firing Ranges Project, along with the current project schedule and milestones. This RmAWP also provides an overview of the technical requirements of the project, including a summary of the approach for the removal activities. Finally, the RmAWP identifies the regulatory requirements and the appropriate removal action responses to address applicable or relevant and appropriate requirements to achieve the project goals of substantially reducing the risk to human health and the environment.
Date: March 1, 1998
Partner: UNT Libraries Government Documents Department


Description: Experiments were conducted in which three selected metals-contaminated mine drainage water samples were treated by chemical precipitation followed by flotation using colloidal gas aphrons (CGAs) to concentrate the precipitates. Drainage water samples used in the experiments were collected from an abandoned turn-of-the-century copper mine in south-central Wyoming, an inactive gold mine in Colorado's historic Clear Creek mining district, and a relatively modern gold mine near Rapid City, South Dakota. The copper mine drainage sample was nearly neutral (pH 6.5) while the two gold mine samples were quite acidic (pH {approx}2.5). Metals concentrations ranged from a few mg/L for the copper mine drainage to several thousand mg/L for the sample from South Dakota. CGAs are emulsions of micrometer-sized soap bubbles generated in a surfactant solution. In flotation processes the CGA microbubbles provide a huge interfacial surface area and cause minimal turbulence as they rise through the liquid. CGA flotation can provide an inexpensive alternative to dissolved air flotation (DAF). The CGA bubbles are similar in size to the bubbles typical of DAF. However, CGAs are generated at ambient pressure, eliminating the need for compressors and thus reducing energy, capital, and maintenance costs associated with DAF systems. The experiments involved precipitation of dissolved metals as either hydroxides or sulfides followed by flotation. The CGAs were prepared using a number of different surfactants. Chemical precipitation followed by CGA flotation reduced contaminant metals concentrations by more than 90% for the copper mine drainage and the Colorado gold mine drainage. Contaminant metals were concentrated into a filterable sludge, representing less than 10% of the original volume. CGA flotation of the highly contaminated drainage sample from South Dakota was ineffective. All of the various surfactants used in this study generated a large sludge volume and none provided a significant concentration factor with this sample. For the ...
Date: June 1, 2002
Creator: Grimes, R. Williams
Partner: UNT Libraries Government Documents Department

Novel Anionic Clay Adsorbents for Boiler-Blow Down Waters Reclaim and Reuse

Description: Our goal in this study is to utilize novel anionic clay sorbents for treating and reclaiming/reusing power-plant effluents, in particular, boiler blow-down waters containing heavy metals, such as As and Se. Developing and using novel materials for such application is dictated by the challenge posed by reclaiming and recycling these too-clean-to-clean effluent streams, generated during electricity production, whose contaminant levels are in the ppm/ppb (or even less) trace levels. During the study model blow-down streams have been treated in batch experiments. Adsorption isotherms as a function of pH/temperature have been established for both As and Se. Adsorption rates have also measured as a function of concentration, temperature, pH, and space time. For both the equilibrium and rate measurements, we have studied the As/Se interaction, and competition from background anions. A homogeneous surface diffusion model is used to describe the experimental kinetic data. The estimated diffusivity values are shown to depend on the particle size. On the other hand, a model taking into account the polycrystalline nature of these adsorbent particles, and the presence of an intercrystallite porous region predicts correctly that the surface diffusivity is particle size independent. A mathematical model to describe flow experiments in packed-beds has also been developed during phase I of this project. The goal is to validate this model with flow experiments in packed-beds during the phase II of this project, to determine the adsorption capacity under flow conditions, and to compare it with the capacity estimated from the adsorption isotherms determined from the batch studies.
Date: December 1, 2005
Creator: Sahimi, Muhammad & Tsotsis, Theodore T.
Partner: UNT Libraries Government Documents Department

Method for high temperature mercury capture from gas streams

Description: A process to facilitate mercury extraction from high temperature flue/fuel gas via the use of metal sorbents which capture mercury at ambient and high temperatures. The spent sorbents can be regenerated after exposure to mercury. The metal sorbents can be used as pure metals (or combinations of metals) or dispersed on an inert support to increase surface area per gram of metal sorbent. Iridium and ruthenium are effective for mercury removal from flue and smelter gases. Palladium and platinum are effective for mercury removal from fuel gas (syngas). An iridium-platinum alloy is suitable for metal capture in many industrial effluent gas streams including highly corrosive gas streams.
Date: April 25, 2006
Creator: Granite, E. J. & Pennline, H. W.
Partner: UNT Libraries Government Documents Department

Environmental significance of biocatalytic conversion of low grade oils

Description: Studies dealing with the interactions between extremophilic microorganisms and crude oils have led to the identification of biocatalysts which through multiple biochemical reactions catalyze desulfurization, denitrogenation, and demetalation reactions in oils. Concurrently, the oils are also converted to lighter oils. These complex biochemical reactions have served as models in the development of the crude oil bioconversion technology to be applied prior to the treatment of oils by conventional chemical processes. In practical terms, this means that the efficiency of the existing technology is being enhanced. For example, the recently introduced additional regulation for the emission of nitrogen oxides in some states restricts further the kinds of oils that may be used in burners. The biocatalysts being developed in this laboratory selectively interact with nitrogen compounds, i.e. basic and neutral types present in the oil and, hence, affect the fuel NOx production. This, in turn, has a cost-efficient influence on the processed oils and their consumption. In this paper, these cost-efficient and beneficial effects will be discussed in terms of produced oils, the lowering of sulfur and nitrogen contents, and the effect on products, as well as the longevity of catalysts due to the removal of heteroatoms and metal containing compounds found in crudes.
Date: September 1, 1996
Creator: Lin, M.S.; Premuzic, E.T.; Lian, H.; Zhou, W.M. & Yablon, J.
Partner: UNT Libraries Government Documents Department

The use of chemical markers in the evaluation of crude oil bioconversion products, technology, and economic analysis

Description: Experimental data gathered over the past several years show that the interactions of microorganisms with crude oils are variable and depend on the microbial species and the chemical composition of crude oils. Systematic studies of chemical mechanisms by which selected microorganisms react with crude oils have led to the identification of biochemical markers characteristic of the interactions of microbes with oils. These biomarkers belong to several groups of natural products ranging from saturate and polyaromatic hydrocarbons containing heterocyclics to organometallic compounds. Chemical marker analyses indicate that the interaction of microbes with crude oils involves multiple chemical reactions resulting from the biochemical interactions between microbes and oils. Different interactions may influence the efficiency of processes in which single or mixed microbial species are used for the oil treatment and may also suggest possible combinations of biological and chemical technologies. Further, the biochemical conversions of oils can be monitored by these chemical markers, which is particularly useful in the optimization of biochemical processing, cost efficiency, and engineering studies. Recent results from these studies are discussed.
Date: March 1, 1996
Creator: Premusic, E.T.; Lin, M.S.; Lian, H.; Zhou, W.M. & Yablon, J.
Partner: UNT Libraries Government Documents Department

Water-soluble metal-binding polymers with ultrafiltration: A technology for the removal, concentration, and recovery of metal ions from aqueous streams

Description: The use of water-soluble metal-binding polymers coupled with ultrafiltration (UF) is a technology under development to selectively concentrate and recover valuable or regulated metal-ions from dilute process or waste waters. The polymers have a sufficiently large molecular size that they can be separated and concentrated using commercially available UF technology. The polymers can then be reused by changing the solution conditions to release the metal-ions, which are recovered in a concentrated form for recycle or disposal. Pilot-scale demonstrations have been completed for a variety of waste streams containing low concentrations of metal ions including electroplating wastes (zinc and nickel) and nuclear waste streams (plutonium and americium). Many other potential commercial applications exist including remediation of contaminated solids. An overview of both the pilot-scale demonstrated applications and small scale testing of this technology are presented.
Date: December 31, 1997
Creator: Smith, B.F.; Robison, T.W. & Jarvinen, G.D.
Partner: UNT Libraries Government Documents Department

Literature search on the use of resins for treatment of radioactive wastes

Description: Over 100 commercial providers with mixed-waste treatability capabilities exist in the US. The maturity level of these technologies varies from a bench scale to a pilot or a commercial scale. The techniques include deactivation, chemical oxidation, recovery of metals, stabilization, vitrification, incineration, biodegradation, and chemical extraction. This report focuses on the use of resins to remove actinides and heavy metals from aqueous waste streams. Only the literature that described resins with high removing efficiency are presented here. The majority of the literature reviewed are proceedings and national or international reports ordered through the Berkeley Lab Library. Some of the reports that the authors requested have not yet arrived. Only a few papers were found in the open literature (journals or magazines). Although this report does not include all existing references, it provides an accurate assessment of efficient resins to be considered for waste minimization procedures. 70 refs.
Date: October 1, 1997
Creator: AlMahamid, I. & Smith, B.M.
Partner: UNT Libraries Government Documents Department

Surface Depletion in the Vacuum Distillation of Metals from Bismuth

Description: Surface depletion was investigated in laboratory- and plant-scale distillation units with mixing by natural convection or by mechanical surface agitation. A model was developed for predicting the degree of surface depletion during the distillation of metals from bismuth as a function of temperature, still pot dimensions, and degree of agitation. This paper discusses those findings.
Date: August 29, 2001
Creator: Bradley, R.F.
Partner: UNT Libraries Government Documents Department

Mercury-binding membranes for flue gas clean-up

Description: All Phase I objectives were met. In the Phase I program, TPL developed a material, T- 450, capable of removing elemental mercury from air. It was found to have high porosity, good mechanical strength, good affinity for aqueous ionic mercury, and good stability to hot acidic gas. The material, used as a granular solid, was tested for adsorption of mercury in two protocols, one involving static room-temperature air and one using flowing hot air. In each case, it was superior to activated carbon. The following results were obtained: 1. Sol-gel methods were found to be applicable for synthesis of silicates containing oxidized thiol (disulfide) groups. 2. Synthetic parameters were determined for silicates with a variety of physical properties and performances. 3. Measurement of physical properties indicate high porosity strength, and stability to conditions found in flue gases. 4. The Hg° adsorption of T-450 was superior to that of activated carbon; static testing indicated a 2.4-fold increase in mercury adsorption, while a flow system mimicking hot flue gas indicated a 3.6-fold increase in Hg adsorption. 5. Economic analysis indicated that T-450 is a strong candidate for scale-up and commercial development. For the cost of removing Hg from flue gas, a savings of 23.5% is estimated, relative to use of activated carbon.
Date: July 31, 2001
Creator: Kroh, Dr. Franklin O. & Morgan, Thane
Partner: UNT Libraries Government Documents Department

Engineering development of advanced physical fine coal cleaning for premium fuel applications

Description: The primary goal of this project is the engineering development of two advanced physical fine coal cleaning processes, column flotation and selective agglomeration, for premium fuel applications. The project scope included laboratory research and bench-scale testing on six coals to optimize these processes, followed by the design, construction and operation of 2 t/hr process development unit (PDU). This report represents the findings of the PDU Advanced Column Flotation Testing and Evaluation phase of the program and includes a discussion of the design and construction of the PDU. Three compliance steam coals, Taggart, Indiana VII and Hiawatha, were processed in the PDU to determine performance and design parameters for commercial production of premium fuel by advanced flotation. Consistent, reliable performance of the PDU was demonstrated by 72-hr production runs on each of the test coals. Its capacity generally was limited by the dewatering capacity of the clean coal filters during the production runs rather than by the flotation capacity of the Microcel column. The residual concentrations of As, Pb, and Cl were reduced by at least 25% on a heating value basis from their concentrations in the test coals. The reduction in the concentrations of Be, Cd, Cr, Co, Mn, Hg, Ni and Se varied from coal to coal but the concentrations of most were greatly reduced from the concentrations in the ROM parent coals. The ash fusion temperatures of the Taggart and Indiana VII coals, and to a much lesser extent the Hiawatha coal, were decreased by the cleaning.
Date: August 28, 1997
Creator: Shields, G.L.; Smit, F.J. & Jha, M.C.
Partner: UNT Libraries Government Documents Department

Evaluation of Sorbent Injection for Mercury Control

Description: The power industry in the U.S. is faced with meeting new regulations to reduce the emissions of mercury compounds from coal-fired plants. These regulations are directed at the existing fleet of nearly 1,100 boilers. These plants are relatively old with an average age of over 40 years. Although most of these units are capable of operating for many additional years, there is a desire to minimize large capital expenditures because of the reduced (and unknown) remaining life of the plant to amortize the project. Injecting a sorbent such as powdered activated carbon into the flue gas represents one of the simplest and most mature approaches to controlling mercury emissions from coal-fired boilers. This is the final site report for tests conducted at DTE Energy's Monroe Power Plant, one of five sites evaluated in this DOE/NETL program. The overall objective of the test program was to evaluate the capabilities of activated carbon injection at five plants: Sunflower Electric's Holcomb Station Unit 1, AmerenUE's Meramec Station Unit 2, Missouri Basin Power Project's Laramie River Station Unit 3, Detroit Edison's Monroe Power Plant Unit 4, and AEP's Conesville Station Unit 6. These plants have configurations that together represent 78% of the existing coal-fired generation plants. The goals for the program established by DOE/NETL were to reduce the uncontrolled mercury emissions by 50 to 70% at a cost 25 to 50% lower than the target established by DOE of $60,000/lb mercury removed. The results from Monroe indicate that using DARCO{reg_sign} Hg would result in higher mercury removal (80%) at a sorbent cost of $18,000/lb mercury, or 70% lower than the benchmark. These results demonstrate that the goals established by DOE/NETL were exceeded during this test program. The increase in mercury removal over baseline conditions is defined for this program as a comparison in the ...
Date: April 30, 2006
Creator: Sjostrom, Sharon
Partner: UNT Libraries Government Documents Department


Description: New technologies are needed that neutralize contaminant toxicity and control physical transport mechanisms that mobilize sediment contaminants. The last 12 months of this comprehensive project investigated the use of combinations of sequestering agents to develop in situ active sediment caps that stabilize mixtures of contaminants and act as a barrier to mechanical disturbance under a broad range of environmental conditions. Efforts focused on the selection of effective sequestering agents for use in active caps, the composition of active caps, and the effects of active cap components on contaminant bioavailability and retention. Results from this project showed that phosphate amendments, some organoclays, and the biopolymer, chitosan, were very effective at removing metals from both fresh and salt water. These amendments also exhibited high retention (80% or more) of most metals indicating reduced potential for remobilization to the water column. Experiments on metal speciation and retention in contaminated sediment showed that apatite and organoclay can immobilize a broad range of metals under both reduced and oxidized conditions. These studies were followed by sequential extractions to evaluate the bioavailability and retention of metals in treated sediments. Metal fractions recovered in early extraction steps are more likely to be bioavailable and were termed the Potentially Mobile Fraction (PMF). Less bioavailable fractions collected in later extraction steps were termed the Recalcitrant Factor (RF). Apatite and organoclay reduced the PMF and increased the RF for several elements, especially Pb, Zn, Ni, Cr, and Cd. Empirically determined partitioning coefficients and modeling studies were used to assess the retention of organic contaminants on selected sequestering agents. Organoclays exhibited exceptionally high sorption of polycyclic aromatic hydrocarbons as indicated by a comparison of K{sub d} values among 12 amendments. These results suggested that organoclays have high potential for controlling organic contaminants. Measured partitioning coefficients were used to model the time ...
Date: November 28, 2007
Creator: Knox, A; Michael Paller, M; Danny D. Reible, D & Ioana G. Petrisor, I
Partner: UNT Libraries Government Documents Department

Demonstration of Mer-Cure Technology for Enhanced Mercury Control

Description: Alstom Power Inc. has completed a DOE/NETL-sponsored program (under DOE Cooperative Agreement No. De-FC26-07NT42776) to demonstrate Mer-Cure{trademark}, one of Alstom's mercury control technologies for coal-fired boilers. The Mer-Cure{trademark}system utilizes a small amount of Mer-Clean{trademark} sorbent that is injected into the flue gas stream for oxidation and adsorption of gaseous mercury. Mer-Clean{trademark} sorbents are carbon-based and prepared with chemical additives that promote oxidation and capture of mercury. The Mer-Cure{trademark} system is unique in that the sorbent is injected into an environment where the mercury capture kinetics is accelerated. The full-scale demonstration program originally included test campaigns at two host sites: LCRA's 480-MW{sub e} Fayette Unit No.3 and Reliant Energy's 190-MW{sub e} Shawville Unit No.3. The only demonstration tests actually done were the short-term tests at LCRA due to budget constraints. This report gives a summary of the demonstration testing at Fayette Unit No.3. The goals for this Mercury Round 3 program, established by DOE/NETL under the original solicitation, were to reduce the uncontrolled mercury emissions by 90% at a cost significantly less than 50% of the previous target of $60,000/lb mercury removed. The results indicated that Mer-Cure{trademark} technology could achieve mercury removal of 90% based on uncontrolled stack emissions. The estimated costs for 90% mercury control, at a sorbent cost of $0.75 to $2.00/lb respectively, were $13,400 to $18,700/lb Hg removed. In summary, the results from demonstration testing show that the goals established by DOE/NETL were met during this test program. The goal of 90% mercury reduction was achieved. Estimated mercury removal costs were 69-78% lower than the benchmark of $60,000/lb mercury removed, significantly less than 50% of the baseline removal cost.
Date: June 1, 2008
Creator: Marion, John; O'Neill, Dave; Taugher, Kevin; Kang, Shin; Johnson, Mark; Pargac, Gerald et al.
Partner: UNT Libraries Government Documents Department


Description: The initial tasks of this DOE funded project to investigate mercury removal by calcium-based sorbents have been completed, and initial testing results have been obtained. Mercury monitoring capabilities have been obtained and validated. An approximately 1MW (3.4 Mbtu/hr) Combustion Research Facility at Southern Research Institute was used to perform pilot-scale investigations of mercury sorbents, under conditions representative of full-scale boilers. The initial results of ARCADIS G&M proprietary sorbents, showed ineffective removal of either elemental or oxidized mercury. Benchscale tests are currently underway to ascertain the importance of differences between benchscale and pilot-scale experiments. An investigation of mercury-capture temperature dependence using common sorbents has also begun. Ordinary hydrated lime removed 80 to 90% of the mercury from the flue gas, regardless of the temperature of injection. High temperature injection of hydrated lime simultaneously captured SO{sub 2} at high temperatures and Hg at low temperatures, without any deleterious effects on mercury speciation. Future work will explore alternative methods of oxidizing elemental mercury.
Date: June 1, 2002
Creator: Gale, Thomas K.
Partner: UNT Libraries Government Documents Department

Enhancement of mercury control in flue-gas cleanup systems

Description: This paper summarizes research at Argonne National Laboratory which is focused on techniques to enhance the capture of elemental mercury and integrate its control into existing flue-gas cleanup (FGC) systems. Both laboratory and field tests have shown that very little elemental mercury is captured in a wet scrubber system due to the low solubility of that species. To enhance the ability of wet scrubbers to capture mercury, Argonne has studied improved mass transfer through both mechanical and chemical means, as well as the conversion of elemental mercury into a more soluble species that can be easily absorbed. Current research is investigating the roles of several halogen species either alone or in combination with typical flue-gas components such as sulfur dioxide and nitric oxide in the oxidation of mercury to form compounds that are easily scrubbed from the flue gas.
Date: July 1, 1996
Creator: Livengood, C.D.; Huang, Hann S.; Mendelsohn, M.H. & Wu, Jiann M.
Partner: UNT Libraries Government Documents Department

Control of toxic metallic emissions formed during the combustion of Ohio coals. Final report, September 1994--March 1996

Description: The objective of this project was to characterize metallic emissions from representative coals and develop strategies for their control. A technique for flue gas desulfurization is the use of calcium based sorbents, and the degree of metals capture of these sorbents under different conditions will be researched. The objective of the first year of the study was to understand the evolution of metallic aerosol size distributions and the capture characteristics of various sorbents. Also, the metallic emissions resulting from the combustion of two seams of Ohio coals were to be characterized. Studies on the evolution of the metallic aerosol size distributions have been completed and the use of silicon and calcium based sorbents for capture of lead species has been examined. Co-injection of metallic compounds along with organometallic silicon indicated a high degree of capture of lead in a certain temperature region. Preliminary results with calcium based sorbents also indicate capture of metallic species. In the second year, the work was extended to examine three different aspects: (1) understanding the mechanisms of capture of metals by vapor phase sorbents; (2) role of chlorine in speciation of metals and its importance in metals capture; and (3) capture of mercury by aerosol transformation. It was established that aerosol formation rates for Hg species is rather slow under typical combustion conditions, and hence would not be an effective way of capture of mercury. However, the use of titania based sorbents have provided exciting results. This is being developed further for effective capture of Hg species in combustion environments. Several theoretical investigations were also carried out to better understand and predict trace metal behavior in combustion environments. Publications and conference presentations resulting from work this year is listed.
Date: March 29, 1996
Creator: Wu, Chang-Yu; Owens, T.M. & Biswas, P.
Partner: UNT Libraries Government Documents Department