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Brick manufacture with fly ash from Illinois coals. Technical report, March 1, 1995--May 31, 1995

Description: This investigation seeks to utilize fly ash in fired-clay products such as building and patio bricks, ceramic blocks, field and sewer tile, and flower pots. This goal is accomplished by 1) one or more plant-scale, 5000-brick tests of fly ash mixed with brick clays at the 20% or higher level; 2) a laboratory-scale study to measure the firing reactions of a range of compositions of clay and fly ash mixtures; 3) a preliminary study to evaluate the potential environmental and economic benefits of brick manufacture with fly ash. Bricks and feed materials will be tested for compliance with market specifications and for leachability of pollutants derived from fly ash. The laboratory study will combine ISGS databases, ICCI-supported characterization methods, and published information to improve predictions of the firing characteristics of Illinois fly ash and brick clay mixtures. Because identical methods are used to test clay firing and coal ash fusion, and because melting mechanisms are the same, improved coal ash fusion predictions are and additional expected result of this research. During this quarter we completed a manufacturing run at Colonial Brick Co. and began laboratory testing of samples from that run: clays, fly ash (from Illinois Power Company`s Wood River plant), and green and fired bricks, with and without fly ash. Bricks with 20% fly ash ``scummed`` during firing, and the fly ash failed to increase oxidation rate or water absorption, which were both expected. We obtained chemical and mineralogical analyses of the fireclays and shales at Colonial and Marseilles Brick Companies and began a series of selective dissolution analyses to more accurately determine the composition of the principal clay minerals in brick clays and the components in fly ash. We began related work of calculating normative mineralogical analyses for all clays and fly ashes that we sample.
Date: December 31, 1995
Creator: Hughes, R.E.; Dreher, G.; Moore, D.; Rostam-Abadi, M.; Fiocchi, T. & Swartz, D.
Partner: UNT Libraries Government Documents Department

Production of inorganic pellet binders from fly-ash. Quarterly report, 1 December 1994--28 February 1995

Description: Fly-ash is produced by all coal-fired utilities, and it must be removed from the plant exhaust gases, collected, and disposed of. While much work has been done in the past to utilize fly-ash rather than disposing of it, we nevertheless do not find widespread examples of successful industrial utilization. This is because past work has tended to find uses only for high-quality, easily-utilized fly-ashes, which account for less than 25% of the fly-ash that is produced. The main factor which makes fly-ashes unusable is a high unburned carbon content. In this project, physical separation technologies are being used to remove this carbon, and to convert these unusable fly-ashes into usable products. The main application being studied for the processed fly-ash is as a binder for inorganic materials, such as iron-ore pellets. Work in the first quarter concentrated on obtaining samples of all of the materials to be used (fly-ash, and magnetite ore), training of personnel on pelletization procedures, obtaining and setting up pelletization apparatus in the MTU laboratories, and running pelletization experiments with bentonite binder to establish a baseline for comparison with the fly-ash binders to be made.
Date: December 31, 1995
Creator: Kawatra, S.K. & Eisele, T.C.
Partner: UNT Libraries Government Documents Department

Disposal of fluidized-bed combustion ash in an underground mine to control acid mine drainage and subsidence

Description: During Phase I (first 18 months) the project is segregated into four areas of reporting: (A) Grout Formulation, (B) Grout Characterization, (C) Water Quality Monitoring, (D) Subsidence Control & Contaminant Transport. The first component involves formulating a grout mixture with appropriate flowability to be used in filling complex mine voids. The Grout Characterization component will determine the flow characteristics of the formulated grout. The Water Quality component involves background monitoring of water quality and precipitation at the Phase III (Longridge) mine site. The last component involves evaluating the strength requirements and the migration of contaminants through the candidate grouts. This report separately discusses progress on all components of the program in order of project subtask.
Date: December 31, 1996
Partner: UNT Libraries Government Documents Department

Utilization of lightweight materials made from coal gasification slags. Quarterly report, June 1--August 31, 1996

Description: Integrated-gasification combined-cycle (IGCC) technology is an emerging technology that utilizes coal for power generation and production of chemical feedstocks. However, the process generates large amounts of solid waste, consisting of vitrified ash (slag) and some unconverted carbon. In previous projects, Praxis investigated the utilization of ``as-generated`` slags for a wide variety of applications in road construction, cement and concrete production, agricultural applications, and as a landfill material. From these studies, we found that it would be extremely difficult for ``as-generated`` slag to find large-scale acceptance in the marketplace even at no cost because the materials it could replace were abundantly available at very low cost. It was further determined that the unconverted carbon, or char, in the slag is detrimental to its utilization as sand or fine aggregate. It became apparent that a more promising approach would be to develop a variety of value-added products from slag that meet specific industry requirements. This approach was made feasible by the discovery that slag undergoes expansion and forms a lightweight material when subjected to controlled heating in a kiln at temperatures between 1400 and 17000F. These results confirmed the potential for using expanded slag as a substitute for conventional lightweight aggregates (LWA). The technology to produce lightweight and ultra-lightweight aggregates (ULWA) from slag was subsequently developed by Praxis. The major objectives of the subject project are to demonstrate the technical and economic viability of commercial production of LWA and ULWA from slag and to test the suitability of these aggregates for various applications. The project goals are to be accomplished in two phases: Phase 1, comprising the production of LWA and ULWA from slag at the large pilot-scale, and Phase 2, which involves commercial evaluation of these aggregates in a number of applications. Accomplishments are described.
Date: December 31, 1996
Partner: UNT Libraries Government Documents Department

Utilization of lightweight materials made from coal gasification slags. Quarterly report, September 1--November 30, 1997

Description: In previous projects, Praxis investigated the utilization of as-generated slags for a wide variety of applications in road construction, cement and concrete production, agricultural applications, and as a landfill material. From these studies, the authors found that it would be extremely difficult for as-generated slag to find large-scale acceptance in the marketplace even at no cost because the materials it could replace were abundantly available at very low cost. It became apparent that a more promising approach would be to develop a variety of value-added products from slag that meet specific industry requirements. This approach was made feasible by the discovery that slag undergoes expansion and forms a lightweight material when subjected to controlled heating in a kiln at temperatures between 1,400 and 1,700 F. These results confirmed the potential for using expanded slag as a substitute for conventional lightweight aggregates (LWA). The technology to produce lightweight and ultra-lightweight aggregates (ULWA) from slag was subsequently developed by Praxis. The major objectives of the subject project are to demonstrate the technical and economic viability of commercial production of LWA and ULWA from slag and to test the suitability of these aggregates for various applications. The project goals are to be accomplished in two phases: Phase 1, comprising the production of LWA and ULWA from slag at the large pilot scale, and Phase 2, which involves commercial evaluation of these aggregates in a number of applications. This document summarizes the Phase 2 accomplishments to date along with the major accomplishments from Phase 1.
Date: December 31, 1997
Partner: UNT Libraries Government Documents Department

Hydrothermal reaction of fly ash. Final report

Description: The reactions which occur when fly ash is treated under hydrothermal conditions were investigated. This was done for the following primary reasons. The first of these is to determine the nature of the phases that form to assess the stabilities of these phases in the ambient environment and, finally, to assess whether these phases are capable of sequestering hazardous species. The second reason for undertaking this study was whether, depending on the composition of the ash and the presence of selected additives, it would be possible under hydrothermal conditions to form compounds which have cementitious properties. Formation of four classes of compounds, which bracket likely fly ash compositional ranges, were selected for study. The classes are calcium silicate hydrates, calcium selenates, and calcium aluminosulfates, and silicate-based glasses. Specific compounds synthesized were determined and their stability regions assessed. As part of stability assessment, the extent to which selected hazardous species are sequestered was determined. Finally, the cementing properties of these compounds were established. The results obtained in this program have demonstrated that mild hydrothermal conditions can be employed to improve the reactivity of fly ash. Such improvements in reactivity can result in the formation of monolithic forms which may exhibit suitable mechanical properties for selected applications as building materials. If the ashes involved are considered hazardous, the mechanical properties exhibited indicated the forms could be handled in a manner which facilitates their disposal.
Date: December 1994
Creator: Brown, P. W.
Partner: UNT Libraries Government Documents Department

Regeneration of FGD waste liquors: Production of ammonium and potassium sulfate mixed fertilizer. Quarterly technical report, October 1993--December 1993

Description: In the 2nd quarterly report, we discussed the lime/limestone process which precipitates N-S containing compounds by adding lime/limestone in a narrow pH range, and which can be an alternative to the K{sub 2}SO{sub 4} process. In this report, we focused on investigations of the lime/limestone process. First, we established an overall flow diagram for the lime/limestone process. Based on the diagram, we performed preliminary experimental investigations to outline practical process conditions. Out major investigations concerned about effects of pH on precipitation of the N-S compounds and precipitation characteristics of N-S compounds in a continuous crystallization system. We also performed an experimental investigation to study crystallization characteristic of the ammonium sulfate in the hydrolysis liquor. In studying effects of pH, we performed batch precipitation of the N-S compounds in a broad range of pH and investigated the effects of pH on the amount of required lime, the amount of the precipitate, and the fraction of N-S compounds precipitated. The result revealed the optimum range for precipitation of N-S compounds to be pH = 7.6--8.6. In studying continuous crystallization characteristics of the N-S compounds, a bench scale 4-liter continuous crystallization system was built to compare a typical Mixed-Suspension-Mixed-Product-Removal (MSMPR) crystallizer and Double-Draw-Off (DDO) crystallizer. In a preliminary test, the DDO was shown to be superior by increasing the average size of the precipitated crystals of N-S compounds from 97 {mu}m to 142 {mu}m and thus enhancing the filterability. In order to obtain information for a practical design of the lime/limestone process, we also set up a material balance for a 300 MWe power plant facility. A preliminary calculation showed that a process on the scale could produce approximately 56 tons ammonium sulfate fertilizer per day.
Date: December 31, 1993
Creator: Randolph, A.D.
Partner: UNT Libraries Government Documents Department

Brick manufacture with fly ash from Illinois coals. Quarterly report, 1 December 1994--28 February 1995

Description: This investigation seeks to utilize fly ash in fired-clay products such as building and patio bricks, ceramic blocks, field and sewer tile, and flower pots. This goal is accomplished by (1) one or more plant-scale, 5000-brick tests with fly ash mixed with brick clays at the 20% or higher level; (2) a laboratory-scale study to measure the firing reactions of a range of compositions of clay and fly ash mixtures; (3) a preliminary study to evaluate the potential environmental and economic benefits of brick manufacture with fly ash. Bricks and feed materials will be tested for compliance with market specifications and for leachability of pollutants derived from fly ash. The laboratory study will combine ISGS databases, ICCI-supported characterization methods, and published information to improve predictions of the firing characteristics of Illinois fly ash and brick clay mixtures. Because identical methods are used to test clay firing and coal ash fusion, and because melting mechanisms are the same, improved coal ash fusion predictions are an additional expected result of this research. If successful, this project should convert a disposal problem (fly ash) into valuable products-bricks. During this quarter we set up the manufacturing run at Colonial Brick Co., finalized arrangements for a larger brick manufacturing run at Marseilles Brick Co. in YR2, revised our laboratory procedures for selective dissolution analysis, obtained information to select three standard fly ashes, and continued our characterization of brick clays that could be mixed with fly ash for fired-clay products. Due to delays in other areas, we began construction of the optimization program for year 2. We discovered recently that fly ash dust will be an unanticipated problem at the brick plant.
Date: December 31, 1995
Creator: Hughes, R.E.; Dreher, G.; Frost, J.; Moore, D.; Rostam-Abadi, M.; Fiocchi, T. et al.
Partner: UNT Libraries Government Documents Department

Production of inorganic pellet binders from fly-ash. Technical report, March 1--May 31, 1995

Description: Fly-ash is produced by all coal-fired utilities, and it must be removed from the plant exhaust gases, collected, and disposed of. While much work has been done in the past to utilize fly-ash rather than disposing of it, we nevertheless do not find widespread examples of successful industrial utilization. This is because past work has tended to find uses only for high-quality, easily-utilized fly-ashes, which account for less than 25% of the fly-ash that is produced. The main factor which makes fly-ashes unusable is a high unburned carbon content. In this project, physical separation technologies are being used to remove this carbon, and to convert these unusable fly-ashes into usable products. The main application being studied for the processed fly-ash is as a binder for inorganic materials, such as iron-ore pellets. In the second quarter, additional fly-ash samples were collected from the E. D. Edwards station (Bartonville, IL). Experimentation was begun to study the removal of carbon from these fly-ashes by froth flotation, and make and test pellets that use fly-ash as binder. During the current quarter, flotation experiments were continued on the fly- ashes. Three types of ashes were studied: 1. Ash from the disposal pond (``wet`` ash); 2. Dry fly-ash collected directly from the standard burners (``low-carbon`` ash); 3. Dry fly-ash collected from the low-NOx burners (``high-carbon`` ash). Each of these was chemically analyzed, and conventional flotation experiments were carried out to determine the optimum reagent dosages for carbon removal. Decarbonized ashes were then made from each ash type, in sufficient quantity to be used in pelletization experiments.
Date: December 31, 1995
Creator: Kawatra, S.K. & Eisele, T.C.
Partner: UNT Libraries Government Documents Department

Conversion of coal wastes into waste-cleaning materials. Quarterly progress report, July 1, 1995--September 30, 1995

Description: In the last three months we studied the phase composition of the fly ash in order to better understand the important parameters in the zeolite formation process using fly ash. In addition, since the zeolites exist in powder form, for practical applications, some ways of binding them into a piece of material is necessary. For that purpose, we began exploring ways of forming porous materials using fly ash. It was found that mixing fly ash, phosphoric acid, and calcium oxide can generate a porous material with good integrity. Meanwhile, the research on forming mesoporous materials from fly ash continued. Some results on the formation of double lamellar phase was found during the study.
Date: December 31, 1995
Creator: Shih, Wei-Heng
Partner: UNT Libraries Government Documents Department

A silica/fly ash-based technology for controlling pyrite oxidation. Semi-annual, March 1, 1996 - August 31, 1996

Description: The overall objective is to develop methodologies by which metasilicate or fly ash may produce an effective coating on pyrite surfaces for inhibiting pyrite oxidation. During the past six months, the investigators produced wet chemistry evidence demonstrating that pyrite-HCO{sub 3} complexes promote pyrite oxidation. This is an important finding for their over all strategy in controlling pyrite oxidation because it suggests that pyrite microencapsulation is important in order to control oxidation in near cirumneutral pH environments produced by addition of alkaline material, e.g., fly ash. In their previous studies, the investigators reported that pyrite microencapsulation could be carried out by reacting pyrite with a pH buffered solution and in the presence of metasilicate. The coating formed on the surface of pyrite appeared to be an amorphous iron-oxide-silicate material which inhibited pyrite oxidation. During this past six months, the investigators evaluated: the molecular mechanisms of silicate adsorption by iron oxide; the effects of silicate on the bulk and surface properties of iron oxides; and the effect of silicate on metal-cation adsorption properties by iron oxides.
Date: December 31, 1996
Creator: Evangelou, V.P.
Partner: UNT Libraries Government Documents Department

Production of elemental sulfur and methane from H{sub 2}S and CO{sub 2} derived from a coal desulfurization process. Annual technical progress report, October 1, 1995--September 30, 1996; Quarterly technical progress report, July 1--September 30, 1996

Description: This annual report summarizes the results of the project during the third year period. The purpose of this study was to develop an experimental and theoretical procedure to investigate the feasibility of producing elemental sulfur, carbon monoxide, hydrogen and possibly methane from hydrogen sulfide and carbon dioxide through catalytic reactions. A standard experimental system that can evaluate potential catalysts under controlled laboratory conditions has been designed and constructed. And an effective simulation program capable of providing valuable thermodynamic information on the reaction system has been compiled. During this project year, the modified experimental system for the catalytic reaction studies was installed and the temperature distribution profile inside the reactor has been characterized. New flowmeters were replaced in the reaction system and calibrated to control the flowrates of H{sub 2}S, CO{sub 2}, H{sub 2} and N{sub 2}. Based on the experimental results of H{sub 2}S decomposition under both non-catalytic and catalytic conditions, bench scale experiments were performed with the CoO-MoO{sub 3}-Alumina catalyst at moderate temperatures, around 550 C, to investigate the adsorption effects using solid sorbents within a sulfur vapor environment. Four kinds of adsorbents have been tested. In addition to the above baseline tests, several designs of solid adsorbent feed system have been tested. Under both an inert and a real reaction environment, bench scale experiments were performed to investigate the characteristics and efficiency of activated carbon passing through the CoO-MoO{sub 3}-Alumina catalyst bed.
Date: December 31, 1996
Creator: Jiang, X.; Khang, S.J. & Keener, T.C.
Partner: UNT Libraries Government Documents Department

Treatment of metal-laden hazardous wastes with advanced clean coal technology by-products. Quartery report, August 1994--November 1994

Description: This first quarterly report describes work during the first three months of the University of Pittsburgh`s (Pitt`s) project on the {open_quotes}Treatment of Metal-Laden Hazardous Wastes with Advanced Clean Coal Technology By-Products.{close_quotes} Participating with Pitt on this project are Dravo Lime Company (DLC), Mill Service, Inc. (MSO and the Center for Hazardous Materials Research (CHMR)). The report states the goals of the project - both general and specific - and then describes the activities of the project team during the reporting period. All of this work has been organizational and developmental in nature. No data has yet been collected. Technical details and data will appear for the first time in the second quarterly report and be the major topic of subsequent reports.
Date: December 1, 1994
Partner: UNT Libraries Government Documents Department

The durability of stabilized flue gas desulfurization sludge

Description: The effects of freeze-thaw cycling on the strength and durability of samples of compacted, stabilized, wet flue gas desulfurization (FGD) by-products are reported. The results of laboratory tests show a clear relationship between higher water contents and increasing vulnerability to freeze-thaw effects. In the samples tested, water contents at or above 40% were characteristic of all the freeze-thaw specimens exhibiting low strengths. Lime content and curing time were also shown to have a marked influence on the durability of the FGD material. It was shown that samples can maintain good strength under freeze-thaw conditions provided 5% lime was added before compaction and the time from compaction to first freeze was at least 60 days.
Date: December 31, 1995
Creator: Chen, X.; Wolfe, W.E. & Hargraves, M.D.
Partner: UNT Libraries Government Documents Department

Simultaneous Hot Gas Desulfurization and Improved Filtration

Description: This research suggests the use of waste metal oxide materials for the removal of sulfur in hot gas streams as an alternative to either traditional calcium based sorbents, or regenerable metal oxide sorbents. When classified to a desired particle size and injected into a high temperature coal utilization process, such a ``once-through`` sorbent can effectively remove sulfur and simultaneously increase the permeability of dust collected at a downstream ceramic filter station in a highly cost effective manner. There is considerable technical and economic promise in the use of waste metal oxides for the removal of sulfur dioxide (SO{sub 2}) and hydrogen sulfide (H{sub 2}S) from coal gas streams containing these components, based upon results from tests under controlled laboratory conditions. Several waste metal oxides, including the oxides of iron, tin, and zinc, have been evaluated both individually and in combination to assess their capacity for sulfur capture in both oxidizing and reducing atmospheres. Additionally, inert materials such as silica sand as well as more traditional materials such as dolomite and limestone, were evaluated as sorbents under identical test conditions to serve as reference data. Efforts also explored the overall domestic availability of the best performing waste metal oxide sorbents, taking into account their geographic distributions, intrinsic value, etc. to provide the groundwork for commercial implementation of a low cost, highly effective sulfur sorbent for eventual use in both coal combustion and coal gasification processes. Recent elevated temperature thermogravimetric analysis (TGA) testing of these samples, performed at the Institute of Gas Technology (IGT), has further confirmed the trends in sulfur affinity which were observed in the preliminary testing.
Date: December 31, 1996
Creator: Eggerstedt, P.M.; Zievers, J.F.; Patel, P.C. & Zievers, E.C.
Partner: UNT Libraries Government Documents Department

Production of cements from Illinois coal ash. Technical report, September 1, 1995--November 30, 1995

Description: The objective of this program is to convert Illinois coal combustion residues, such as fly ash, bottom ash, and boiler slag, into novel cementitious materials for use in the construction industry. Currently only about 30% of the 5 million tons of these coal combustion residues generated in Illinois each year are utilized, mainly as aggregate. These residues are composed largely Of SiO{sub 2}, Al{sub 2}O{sub 3}, Fe{sub 2}O{sub 3}, MgO, and CaO, which are also the major components of cement. The process being developed in this program will use the residues directly in the manufacture of cement products. Therefore, a much larger amount of residues can be utilized. To achieve the above objective, in the first phase (current year) samples of coal combustion residues will be blended and mixed, as needed, with a lime or cement kiln dust (CKD) to adjust the CaO composition. Six mixtures will be melted in a laboratory-scale furnace at CTL. The resulting products will then be tested for cementitious properties. Two preliminary blends have been tested. One blend used fly ash with limestone, while the other used fly ash with CKD. Each blend was melted and then quenched, and the resulting product samples were ground to a specific surface area similar to portland cement. Cementitious properties of these product samples were evaluated by compression testing of 1-inch cube specimens. The specimens were formed out of cement paste where a certain percentage of the cement paste is displaced by one of the sample products. The specimens were cured for 24 hours at 55{degrees}C and 100% relative humidity. The specimens made with the product samples obtained 84 and 89% of the strength of a pure portland cement control cube. For comparison, similar (pozzolanic) materials in standard concrete practice are required to have a compressive strength of at ...
Date: December 31, 1995
Creator: Wagner, J.C.; Bhatty, J.I. & Mishulovich, A.
Partner: UNT Libraries Government Documents Department

Utilization of Lightweight Materials Made from Coal Gasificaiton Slags

Description: The integrated gasification combined-cycle (IGCC) coal conversion process has been demonstrated to be a clean, efficient, and environmentally acceptable method of generating power; however, it generates solid waste materials in relatively large quantities. For example, a 400-MW power plant using 4000 tons of 10% ash coal per day may generate over 440 tons/day of solid waste of slag, consisting of vitrified mineral matter and unburned carbon. The disposal of the wastes represents significant costs. Regulatory trends with respect to solid wastes disposal, landfill development costs and public concern make utilization of solid wastes a high-priority issue. As coal gasification technologies find increasing commercial applications for power generation or production of chemical feed stocks, it becomes imperative that slag utilization methods be developed, tested and commercialized in order to offset disposal costs. Praxis is working on a DOE/METC funded project to demonstrate the technical and economic feasibility of making lightweight and ultra-lightweight aggregates from slags left as solid by-products from the coal gasification process. The project objectives are to develop and demonstrate the technology for producing slag-based lightweight aggregates (SLA), to produce 10 tons of SLA products with different unit weights from two slags, to collect operational and emissions data from pilot-scale operations, and to conduct laboratory and commercial scale evaluations of SLA with conventional lightweight and ultra-lightweight aggregates.
Date: December 31, 1996
Creator: Choudhry, V. & Hadley, S.
Partner: UNT Libraries Government Documents Department

Separation of flue-gas scrubber sludge into marketable products. Fourth year, first quarterly technical progress report, September 1, 1996--December 31, 1996 (Quarter No. 13)

Description: To reduce their sulfur emissions, many coal-fired electric power plants use wet flue-gas scrubbers. These scrubbers convert sulfur oxides into solid sulfate and sulfite sludge, which must then be disposed of. This sludge is a result of reacting limestone with sulfur dioxide to precipitate calcium sulfite and calcium sulfate. It consists of calcium sulfite (CaSO{sub 3}{circ}0.5H{sub 2}O), gypsum (CaSO{sub 4}{circ}2H{sub 2}O), and unreacted limestone (CaCO{sub 3}) or lime (Ca(OH)2), with miscellaneous objectionable impurities such as iron oxides, silicates, and magnesium, sodium, and potassium oxides or salts. These impurities prevent many sludges from being utilized as a replacement for natural gypsum, and as a result they must be disposed of in landfills, which presents a serious disposal problem. Knowledge of scrubber sludge characteristics is necessary for the development of purification technologies which will make it possible to directly utilize scrubber sludges rather than landfilling them. This project is studying the use of minimal-reagent froth flotation as the purification process, using the surface properties of the particles of unreacted limestone to remove them and their associated impurities from the material, leaving a purified calcium sulfite/gypsum product.
Date: December 1, 1996
Creator: Kawatra, S.K. & Eisele, T.C.
Partner: UNT Libraries Government Documents Department

Landslide remediation on Ohio State Route 83 using clean coal combustion by-products

Description: In the present work, a flue gas desulfurization (FGD) by-product was used to reconstruct the failed portion of a highway embankment. The construction process and the stability of the repaired embankment are examined. State Route 83 in Cumberland, Ohio has been damaged by a slow moving slide which has forced the Ohio Department of Transportation to repair the roadway several times. In the most recent repair FGD by-products obtained from American Electric Power`s Tidd PFBC plant were used to construct a wall through the failure plane to prevent further slippage. In order to evaluate the utility of using coal combustion by-products in this type of highway project the site was divided into three test sections. In the first repair section, natural soil removed form the slide area was recompacted and replaced according to standard ODOT construction practices. In the second section the natural soil was field mixed with the Tidd PFBC ash in approximately equal proportions. The third section was all Tidd ash. The three test sections were capped by a layer of compacted Tidd ash or crushed stone to provide a wearing surface to allow ODOT to open the roadway before applying a permanent asphalt surface. Measurement of slope movement as well as water levels and quality have begun at the site in order to evaluate long term project performance. The completion of this project should lead to increased acceptance of FGD materials in construction projects. Monetary savings will be realized in avoiding some of the disposal costs for the waste, as well as in the reduced reliance on alternative engineering materials.
Date: December 31, 1995
Creator: Payette, R.; Chen, X.Y.; Wolfe, W. & Beeghly, J.
Partner: UNT Libraries Government Documents Department

Utilization of low NOx coal combustion by-products. Quarterly report, April 1 - June 30, 1996

Description: This project is studying a beneficiation process to make power plant fly ash a more useful by-product. Accomplishments for this reporting period are presented for the following tasks: laboratory characterization which includes sample collection, material characterization and laboratory testing of ash processing operations; product testing including concrete, concrete block/brick, plastic fillers and activated carbon; and market and economic analysis. Appendix A contains data on fly ash material characterization--major elemental analysis by size.
Date: December 31, 1996
Partner: UNT Libraries Government Documents Department

Stabilization of DOE hazardous wastes with clean-coal technology by-products

Description: The objective of this research is to evaluate both the long term and short term stabilization of DOE metal-containing hazardous wastes with clean coal technology (CCT) by-products. This work builds directly on a currently funded DOE/METC project with the University of Pittsburgh (prime contractor) in conjunction with Mill Service (a centralized waste treater), and Dravo Lime Corporation. Studies fall into two categories: (1) observation of the ability of CCT to stabilize and solidify characteristic toxic/hazardous metal-laden wastes (and other DOE metal containing wastes) over the near term via conversion of such wastes into a non-hazardous form by means of pozzolanic type reactions with by-products, and; (2) characterization and understanding of the longer term environmental and physical stability of the resultant solidified matrix in terms of potentially time dependent physical and chemical/toxicological leaching characteristics taking place due to slow solid phase crystalline reactions.
Date: December 31, 1996
Creator: Neufeld, R.D. & Cobb, J.T.
Partner: UNT Libraries Government Documents Department

Mixed waste treatment using the ChemChar thermolytic detoxification technique

Description: The diversity of mixed waste matrices contained at Department of Energy sites that require treatment preclude a single, universal treatment technology capable of handling sludges, solids, heterogeneous debris, aqueous and organic liquids and soils. Versatility of the treatment technology, volume reduction and containment of the radioactive component of the mixed waste streams are three criteria to be considered when evaluating potential treatment technologies. The ChemChar thermolytic detoxification process being developed under this R and D contract is a thermal, chemically reductive technology that converts the organic portion of a mixed waste stream to an energy-rich synthesis gas while simultaneously absorbing volatile inorganic species (metals and acid gases) on a macroporous, carbon-based char. The latter is mixed with the waste stream prior to entering the reactor. Substoichiometric amounts of oxidant are fed into the top portion of the cylindrical reactor generating a thin, radial thermochemical reaction zone. This zone generates all the necessary heat to promote the highly endothermic reduction of the organic components in the waste in the lower portion of the reactor, producing, principally, hydrogen and carbon monoxide. The solid by-product is a regenerated carbon char that, depending on the inorganic loading, is capable for reuse. The in situ scrubbing of contaminants by the char within the reactor coupled with a char filter for final polishing produce an exceptionally clean synthesis gas effluent suitable for on-site generation of heat, steam or electricity. Despite the elevated temperatures in the thermochemical reaction zone, the reductive nature of the process precludes formation of nitrogen oxides and halogenated organic compound by-products.
Date: December 31, 1995
Creator: Kuchynka, D.
Partner: UNT Libraries Government Documents Department

Desulfurization of coal: Enhanced selectivity using phase transfer catalysts. Technical report, September 1--November 30, 1995

Description: Due to environmental problems related to the combustion of high sulfur Illinois coal, there continues to be interest in the development of viable pre-combustion desulfurization processes. Recent studies by the authors have obtained very good sulfur removals but the reagents that are used are too expensive. Use of cheaper reagents leads to a loss of desired coal properties. This study investigates the application of phase transfer catalysts to the selective oxidation of sulfur in coal using air and oxygen as oxidants. The phase transfer catalyst is expected to function as a selectivity moderator by permitting the use of milder reaction conditions than otherwise necessary. This would enhance the sulfur selectivity and help retain the heating value of the coal. The use of certain coal combustion wastes for desulfurization, and the application of cerium (IV) catalyzed air oxidations for selective sulfur oxidation are also being studied. If successful this project could lead to the rapid development of a commercially viable desulfurization process. This would significantly improve the marketability of Illinois coal. During this quarter aliquots of the IBC-101 coal have been ground to various particle sizes in an attempt to find the optimum physical pretreatment for mineral, especially pyrite, removal. Analysis of these various aliquots shows them to be representative of the original coal. In addition, preliminary desulfurization reactions using fly ash and scrubber sludges have been performed on an unoxidized IBC-101 sample. Results will be available next quarter. Also, SEM-EDAX analysis of the fly ash indicates that it contains oxides that have shown activity in base desulfurization reactions.
Date: December 31, 1995
Creator: Palmer, S.R. & Hippo, E.J.
Partner: UNT Libraries Government Documents Department

Manufacture of ammonium sulfate fertilizer from FGD-gypsum. Technical report, September 1--November 30, 1994

Description: The overall goal of this project is to assess the technical and economic feasibility for producing commercial-grade ammonium sulfate fertilizer from gypsum produced as part of limestone flue gas desulfurization (FGD) processes. This is a cooperative effort among the ISGS, the UIUC, AlliedSignal, SE-ME, Henry Fertilizer, Illinois Power Co. (IP), and Central Illinois Public Services (CIPS). Bench-scale experiments will be conducted to obtain process engineering data for manufacture of ammonium sulfate from FGD-gypsum and to help evaluate technical and economical feasibility of the process. Controlled greenhouse experiments will be conducted at UIUC to evaluate the chemical impact of the produced ammonium sulfate on soil properties. A process flow sheet will be proposed and market demand for the products will be established. An engineering team at IP will provide an independent review of the economics of the process. AlliedSignal will be involved in testing and quality evaluation of ammonium sulfate samples and is interested in an agreement to market the finished product. CIPS will provide technical assistance and samples of FGD-gypsum for the project. In this quarter, a literature study that should give detailed insight into the chemistry, process schemes, and costs of producing ammonium sulfate from gypsum is in progress at the ISGS. Acquisition of a high quality FGD-gypsum sample was completed. Collecting of the other lower grade sample was scheduled to be conducted in December. Characterization of these feed materials is in progress.
Date: December 31, 1994
Creator: Chou, M.I.M.; Rostam-Abadi, M.; Lytle, J.M.; Hoeft, R.; Blevins, F.Z. & Achron, F.
Partner: UNT Libraries Government Documents Department