AndreaBozzo/ceres-open-data-index huggingface dataset:
Wet carbonization of lump-size low-rank coals by a novel non-slurry approach. Progress report, February-April 1985

Work continued this quarter on the design and procurement of equipment to construct the wet-carbonization process research unit designed to process about 100 lb/h of as-received coal. Eight batch set-carbonization tests were conducted this quarter. Tests have now been conducted with all four coals specified in the approved test plan. The operating conditions for the tests were temperatures, pressures, and residence times in the range of 400/sup 0/ to 650/sup 0/F, 250 to 3300 psia, and 0 to 60 minutes, respectively. Results to date show that overall component conversions for the two North Dakota lignites are similar for the tests conducted at comparable conditions. The Texas lignite is less reactive and the Montana subbituminous is significantly less reactive than the North Dakota lignites. Handling characterization tests were conducted with raw and wet-carbonized coals. These tests include drop-shatter tests, equilibrium moisture content determinations, bulk and particle measurements, and particle shrinkage determinations. Particle-size reduction due to drop-shatter testing of wet-carbonized coal was greater than that of the corresponding feed coal and increased with wet-carbonization severity. However, the raw coal decrepitated (crumbled) much more readily than the air-dried wet-carbonized coal. Bulk density decreased by about 2% with increasing wet-carbonization temperature, but differed by less than 2% from the corresponding raw coal bulk density. Anaerobic biogasification potential assays were conducted this quarter to determine the biodegradability of liquid product samples from the batch wet-carbonization tests. After 60 days of incubation at 35/sup 0/C, no gas production from any of the samples was observed. Gas production was observed, however, in a diluted sample, indicating that the organisms were being acclimated to the liquid product at dilute concentrations. 20 figs., 12 tabs.

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Development of an advanced water-gas shift conversion system. Final report

Pacific Northwest Laboratory has completed initial exploratory research to investigate the chemistry and use of a pressurized aqueous catalyst system for conducting the water-gas shift reaction. The research was done under sponsorship of the USDOE Morgantown Energy Technology Center. A 1.0 liter continuous bench scale reactor system was built and operated to investigate water-gas shift chemistry at high pressure. Details regarding the chemistry of the aqueous, base-catalyzed system in both batch and continuous reactors are presented for a temperature range of 200 to 350/sup 0/C and pressures from 500 to 3000 psig. The catalyst choice is sodium carbonate at a concentration of 6% in water, but any material which can generate hydroxide ions at the process conditions will effectively catalyze the reaction. This report summarizes the results of the bench-scale research on the concept and presents a discussion of optimum operating conditions, pressure effects and limitations, kinetic data, effects of gas flow rates, catalyst type, and preliminary concept evaluation. 16 refs., 29 figs., 8 tabs.

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Pulsating gasification of low-rank coals. Quarterly technical progress report, October 1, 1985-December 31, 1985

This report describes the work performed during the fifth quarter of the contract. During this quarter, parametric studies were conducted with the newly developed pulsating coal gasification code. Solutions were obtained by assuming that (1) initially the raw coal particles were uniformly distributed throughout the gasifier and (2) initially the raw coal particles were present only in the inlet section of the gasifier. Also, the effect of the following parameters were investigated: (1) the inlet gas temperature, (2) the inlet particle temperature, (3) the mass flow rate entering the gasifier, and (4) the coal particle loading at the gasifier inlet. The results of these various studies are presented and discussed in this report. Also, during this quarter the detailed design of the gasifier to be used in the experimental phase of this program was completed and the details are presented in this report. 2 refs., 10 figs.

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Characterization of particles entrained in the effluent gases of an 18-inch AFBC

This experimental investigation was directed at measurements of the mass loading and size distribution of the particles entrained in the effluent gases of the Morgantown Energy Technology Center (METC) 18-inch, atmospheric pressure fluidized-bed combustor (AFBC). This information was required to aid in the continuing characterization of the AFBC, and to assess the efficiency or performance of an associated cleanup device. The particle-laden flow from the AFBC was introduced into a prototype granular-bed filter (GBF) designed for hot gas cleanup. In order to assess the efficiency of the GBF for particle removal, the mass loading and size distribution of particles contained in the cleaned gas emerging from the GBF were also determined. The effluent gases exit the AFBC at a nominal 1500/sup 0/F and a heavy particle loading (>1 g/scm). These conditions represent a harsh sampling environment. Filter samples obtained by extractive sampling formed the basis of the experimental information. Gravimetric and Coulter counter analyses were performed on each sample to provide mass loading and particle size data, respectively. Mass loadings of particles, as determined from filter samples collected at the inlet and outlet of the GBF, indicated particle removal efficiencies of about 80%. No significant variation in the particle removal efficiency was observed. Analysis of collected particulate samples showed no significant preferential removal of particles as a function of particle size. 2 figs., 1 tab.

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Thermal dewatering of coal. Fifth quarterly progress report, April 1-June 30, 1985

This communication describes changes in the macromolecular structure of a lignite and a bituminous coal during rapid pyrolysis in the temperature range 300 to 1200 K. Solvent swelling techniques have clearly demonstrated that crosslinking occurs in lignites at somewhat lower pyrolysis temperatures than it does in bituminous coals. The onset of the crosslinking processes in bituminous coals coincides with the end of the tar formation period. In lignites, crosslinking occurs very early in the pyrolysis process, coinciding with low temperature release of CO/sub 2/. The presence of natural moisture in the lignite appears to have a significant effect on pyrolysis chemistry, increasing the amount of crosslinking observed at any temperature. 14 refs., 6 figs.

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High-temperature, high-pressure flash pyrolysis of Montana Rosebud coal

Experiments covering a broad range of reaction conditions are being conducted to determine and model the effects of coal gasification environments on product yields. The research uses a 3-in ID, downflow entrained reactor that turbulently mixes preheated gases with coal to achieve high particle heating rates. As part of a comprehensive experimental program, pyrolysis tests reacting Montana Rosebud subbituminous coal in a nitrogen-argon atmosphere were completed to provide baseline yield data for eventual comparison with tests in reactive environments. The tests consisted of a three-variable, composite factorially designed series, a single test at extreme reaction conditions, and a limited series to investigate particle size effects. Experimental conditions ranged from 1500/sup 0/ to 2500/sup 0/F reaction temperature, 100 to 900 psig pressure, 2.19 to 10.00 s gas residence time, with gas preheat temperatures up to 3000/sup 0/F. This report provides the basis and background of this work; describes experimental equipment, procedures, and design; presents test data and regression model analyses; and discusses statistically significant trends in relation to the current understanding of devolatilization and secondary reaction phenomena. 29 refs., 98 figs., 75 tabs.

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Thermal dewatering of coal. Seventh quarterly progress report, October 1-December 31, 1985

This report summarizes information concerning the sorption isotherms of water on four lignite samples. The four lignite samples are all from North Dakota and have been described in detail in earlier quarterly reports of this project. The earlier measurements of sorption isotherms at 30/sup 0/C have now been supplemented by data obtained at 50 and 60/sup 0/C. From these data, isosteric heats of sorption may be calculated. In addition to the data on the sorption of water by the as-received lignites, the present report also examines data on the sorption of water by demineralized samples. This work was motivated by a need to know whether cations or mineral species might play a role in moisture retention on the lignites. Clearly, the design of a thermal dewatering process could be influenced by a large extent of moisture retention by mineral species which are unaffected by mild pyrolytic treatment. Data now in hand imply a significant amount of moisture is held by inorganic species. 3 refs., 2 figs.

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Surface adhesion of low-rank coal ash. Quarterly technical progress report, October 1, 1985-December 31, 1985

The percentage of ion-exchangeable cations was determined for the Center lignite. The ion-exchanged material was produced by treating the lignite with ammonium acetate which upon heating yields hydrogen attached to carboxyl groups. The amount of exchangeable sodium was found to be 95 percent while the amount of exchangeable calcium was 46 percent. Adhesive properties of the Center lignite ash were evaluated using the sticking apparatus developed by Abbott, Moza and Austin. The minimum substrate temperature for adherence (sticking temperature) was found to be 375/sup 0/C for Center ash. The adhesive strength of the slag to the substrate increased almost logarithmically when the substrate temperature was increased in the range up to 525/sup 0/C. A vertical tube furnace was used to grow deposits on cooled boiler steel substrates, providing a means to gain knowledge as to coal specific behavior related to ash deposition. The rate of ash deposition was measured with regard to ion-exchanged coals and hot zone temperature. The effect of removing the ion-exchangeable cations from Center lignite did not significantly change the rate of deposition. The strength of the deposits formed from the ion-exchangeable Center were markedly reduced as compared to the Center lignite due to decreased availability to alkali and alkaline earth elements which may be responsible for liquid phase sintering of the ash. The crystalline species consisted of anorthite and pyroxene with minor and trace amounts of gehlenite. Hot zone temperature had no effect on deposition rates for Center or ion-exchanged Center lignite, but the deposits formed from combustion in a hot zone temperature of 1500/sup 0/C had greater strengths than at 1400/sup 0/C. In the ion-exchanged coals the deposit strength was weaker at a hot zone temperature 1400/sup 0/C as compared to 1500/sup 0/C.

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Summary report on physical and chemical treatment of UCG condensate and affected groundwaters

Several unit operations were evaluated for ability to treat Hanna IVB UCG condensate and UCG-affected groundwaters. These treatment processes included coagulation-precipitation, reverse osmosis (RO), ultrafiltration (UF), microporous filtration (MPF), and carbon-adsorption with coal and char. The objectives of the experiments were to remove colloidal and suspended solids, dissolved inorganics, and soluble organics from UCG wastewaters. In coagulation-precipitation experiments, a 60 mg/L dose of polymer Purifloc C-31 resulted in removal of 99.0% of the 2 to 90 ..mu..m-diameter particles and 92.9% of the acetone-soluble tar from Hanna IVB condensate. Similarly, addition of 50 gm/L of polymer DEAE-Dextran resulted in removal of 98.3% of the 2-90 ..mu..m-diameter particles and 95.2% of the acetone-soluble tar. Reverse osmosis treatment of Hanna groundwater reduced sulfate and total dissolved solids by 99.4% and 98.9%, respectively. Acetone-soluble tar was reduced by 77.0% during a UF experiment performed with a 50% conversion rate. Removals of soluble organics by UF were negligible, however. Treatment of simulated wastewater by MPF with powdered-activated-carbon addition effected much greater removals of dissolved organic carbon and phenols. Metals were also successfully removed by this configuration. Total organic carbon (TOC) and phenols in simulated wastewater were effectively adsorbed onto coal and char. The TOC removals by adsorbents were 71.4 to 92.6% with simulated wastewater and 11.2 to 37.5% with Hanna IVB condensate. The adsorption of TOC from simulated wastewater onto coal was well described by both the Langmuir and Freundlich isotherm models. The Freundlich isotherm best described the adsorption of TOC from simulated wastewater onto char. The adsorption of contaminants from Hanna IVB UCG condensate was poorly described by both isotherm models. 18 refs., 16 figs., 12 tabs.

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Scale-up of miscible flood processes

Results of a wide-ranging investigation of the scaling of the physical mechanisms of miscible floods are reported. Advanced techniques for analysis of crude oils are considered in Chapter 2. Application of supercritical fluid chromatography is demonstrated for characterization of crude oils for equation-of-state calculations of phase equilibrium. Results of measurements of crude oil and phase compositions by gas chromatography and mass spectrometry are also reported. The theory of development of miscibility is considered in detail in Chapter 3. The theory is extended to four components, and sample solutions for a variety of gas injection systems are presented. The analytical theory shows that miscibility can develop even though standard tie-line extension criteria developed for ternary systems are not satisfied. In addition, the theory includes the first analytical solutions for condensing/vaporizing gas drives. In Chapter 4, methods for simulation of viscous fingering are considered. The scaling of the growth of transition zones in linear viscous fingering is considered. In addition, extension of the models developed previously to three dimensions is described, as is the inclusion of effects of equilibrium phase behavior. In Chapter 5, the combined effects of capillary and gravity-driven crossflow are considered. The experimental results presented show that very high recovery can be achieved by gravity segregation when interfacial tensions are moderately low. We argue that such crossflow mechanisms are important in multicontact miscible floods in heterogeneous reservoirs. In addition, results of flow visualization experiments are presented that illustrate the interplay of crossflow driven by gravity with that driven by viscous forces.

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The effects of halides on the performance of coal gas-fueled molten carbonate fuel cells: Final report, October 1986-October 1987

This report presents the results of a program to determine the probable tolerable limits of hydrogen chloride and hydrogen fluoride present in the fuel and oxidant streams of molten carbonate fuel cells that are operating on gasified coal. A literature survey and thermodynamic analyses were performed to determine the likely effects of halides on cell performance and materials. Based on the results of these studies, accelerated corrosion experiments and electrode half-cell performance tests were conducted using electrolyte which contained chloride and fluoride. These data and the results of previous in-cell tests were used to develop a computer for predicting the performance decay due to these halides. The tolerable limits were found to be low (less than 1 PPM) and depend on the power plant system configuration, the operating conditions of the fuel cell stack, the cell design and initial electrolyte inventory, and the ability of the cell to scrub low levels of halide from the reactant streams. The primary decay modes were conversion of the electrolyte from pure carbonate to a carbonate-halide mixture and accelerated electrolyte evaporation. 75 figs., 16 tabs.

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Methodology and concepts for the design of surface storage fills at the Anvil Points Oil Shale Retort Facility

Primary objectives in design of surface disposal fills for processed and raw oil shales are: (a) to insure long-term physical stability, and (b) to prevent surface runoff, surface erosion, and possible subsurface seepage from degrading the water quality of streams and ground water, it was concluded that the analysis and design of spent shale disposal fills should be based on sound geotechnical engineering principles, considerable experience, and good judgment. An understanding of the source of variability of spent shale materials and its effect on engineering properties is a first step in developing fill design. A second important step is the assessment of long-term changes in the properties of spent shale within a disposal fill. This assessment requires consideration of possible thermal, hydrochemical, and physical interactions within the fill and between the fill and site environment. The site environment is site-specific and depends on the geological, surface and subsurface hydrological, and geotechnical characteristics of the site. The variability of spent shale materials is a direct function of variations in mineral and chemical composition of the raw shale and of the processes applied. Current technology for the design and construction of spent shale disposal fills has not been proven by experience. A major problem is the large quantities of spent shale generated for surface disposal and the lack of available sites other than large gulches in the oil shale country of the western United States. Conceptual research fill designs developed in this study should be refined and constructed to provide needed information on in situ properties and long-term performance. Research fills planned by others should be augmented to obtain needed information, especially for codisposal of spent shales with treated waste water, raw shale fines, and process dust.

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Development of a simple fluidized-bed coal combustion model for the assessment of a pressurized fluidized-bed combustion system for electrical power generation

This report summarizes the state-of-the-art in the mathematical modeling of fluidized-bed coal combustors with the goal of evolving a general framework which will be appropriate for developing a system model for the fluidized-bed coal combustion and power generation technology. Consequently, no attempt is made to generate a functional model, but instead a very simple model is proposed as a first step. The model considers all the essential ingredients of coal combustion and sulfur absorption in fluidized-bed reactors. These are coal devolatilization, char combustion in a bed of dolomite or calcium carbonate, sulfur retention in the fluidized-bed elutriation from the bed, and heat removal by cooling tubes imbedded in the bed. The model is presented and a numerical scheme is proposed which will permit the calculation of bed temperature, coal combustion efficiency, sulfur retention, flue gas composition, and overflow from the bed. Numerical results are presented in which the dependence of the various combustion and operating parameters is examined.

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Advanced design for pulsed atmospheric fluidized bed combustion. Final report

In a pulsed bed, the fluidizing air is made to oscillate while flowing through the bed. The objectives of the work reported were to investigate the potential advantages and limitations of a pulsed atmospheric fluidized bed combustor, based on existing data and analyses, to develop conceptual bench-scale designs, and to formulate a research and development plan for experimental validation and development of the pulsation concept for improving the performance of an AFBC. (LEW)

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New concepts for improving oil recovery in CO/sub 2/ flooding. Quarterly report, April 1-June 30, 1986

This project evaluates the potential of increasing the oil recovery when utilizing CO/sub 2/ flooding. This will be done in two ways: (1) examining the effects of injecting CO/sub 2/ in a line drive manner rather than from a single wellbore; and (2) evaluating the ability of CO/sub 2/ to dissolve monomers such as ethylene, then polymerize the monomers to increase the density and viscosity of CO/sub 2/. Work on the contract this quarter has proceeded satisfactorily, especially in the polymer work. A series of experiments were conducted with the apparatus in order to determine its ability to operate as desired. These experiments are discussed in detail. The 2-D simulator has been going through some modifications in order to make data acquisition easier and to eliminate some of the freezing problems that have developed on the production side of the apparatus.

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A 32-month gasifier mechanistic study and downstream unit process development program for the pressurized ash-agglomerating fluidized bed gasification system: Quarterly report, April 1-June 30, 1985

The design report for the KRW external hot gas cleanup system is in progress. The second air-blown gasifier PDU test for evaluation of in-bed desulfurization was completed. Gasifier operability with in-bed desulfurization was demonstrated by successful operation of the PDU. This success was attributed to improved operation of the dolomite feeder, operational flexibility of the modified ash annulus gas distributors, and specific gasifier startup and transition strategies. The solid wastes discharged from the PDU gasifier during in-bed desulfurization testing include a mixture of agglomerate ash and spent sorbent. The spent sorbent (calcium sulfide) can be converted to calcium sulfate during the in-bed desulfurization process. This is a chemical reaction which minimizes the reactive waste's hazardous properties. Disposal studies and characterization of the PDU reactive wastes were initiated. In addition, process performance was analyzed in terms of gasification rate and product gas composition for selected PDU tests. Work continued to develop process models to enhance predictions of gasifier performance. An evaluation of PDU test data (1983 to 1985) is in progress to compare PDU fines collection and recycle performance based on isokinetic solids measurements versus predicted values. Preliminary results suggest that further reductions in fines loss can be achieved at the PDU by modifying the geometry of the secondary cyclone.

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