AndreaBozzo/ceres-open-data-index huggingface dataset:
Coal gas desulfurization at high temperatures. Status of METC investigations

This report, which consists of data only, documents the continuing effort at the US Department of Energy/Morgantown Energy Technology Center (METC) develop a hot gas desulfurization (HGD) process for coal-derived gas. Previous reports have documented the testing of metal oxide sorbents on lab-scale test equipment. These tests were supported by thermodynamic calculations to determine the equilibrium levels of H/sub 2/S attainable with metal oxide sorbents at high temperatures. Early testing of iron oxide and zinc oxide sorbents led to the development of a zinc ferrite (ZnFe/sub 2/O/sub 4/) sorbent. Zinc ferrite was shown to be regenerable and capable of lowering the sulfur level in hot (1000 to 1200/sup 0/F) coal derived gas to less than 10 ppM. A skid-mounted test unit was designed, fabricated, and installed on a sidestream of the DOE/METC fixed bed gasifier. Four series of tests were conducted during four gasifier runs between June 1983 and December 1983. The zinc ferrite based hot gas desulfurization process was on stream a total of 341 hours during 13 sulfidations. Nine regenerations were also conducted, adding an additional 169 hours to the total run time. The fixed bed gasifier supplying gas to the hot gas desulfurization test unit was fed various coals during these tests. Oxidant to the gasifier was air for the most part, but there were periods of oxygen blown operation. Performance of the Zinc Ferrite Hot Gas Desulfurization Test Unit was generally good. Sulfur levels in the coal gas was generally lowered below 10 ppM. Some carbon deposition was experienced in the HGD reactor. However, this was removed during regeneration. Due to variations in gasifier operating conditions and HGD operating conditions, long-term operating characteristics were not determined. 15 references, 7 figures, 5 tables.

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Great Plains ASPEN model development:  Stretford Sulfur Recovery Plant. Final topical report

An ASPEN model has been developed of the Stretford Sulfur Recovery, Section 4000, of the Great Plains Gasification Plant. The bases for this model are the process description given in Section 3.4.13 of the Great Plains Project Management Plan, and Lummus flowsheet E-7102-250-3. In the Stretford process, H2S is dissolved in an aqueous solution containing a reducing agent that reduces the H2S to sulfur. The solution is buffered with sodium carbonate. The vapor-liquid equilibrium involves ionic species. Because ionic equilibrium calculations are unavailable in ASPEN, except in the FLASH block, the model treats the two absorbers as two SEP blocks. A second model also was prepared with ten flash stages using ionic equilibrium. This model can be used to predict the H2S recovery in the absorbers, and the recovery factor then can be used in the overall model. The ASPEN model that has been developed calculates the material and energy balances of the entire flowsheet, and the equipment duties for a given set of process conditions. The entire set of gasifier raw gas components is used. The K-values for all of the flash blocks are calculated using the Peng-Robinson equation of state, modified for water. Values of the parameters for the gases in water were subjected to regression analysis, and included in the insert file PRKIJ. Because of the lack of data, no consideration was given to the effect on solubility of the ionic species. Table 10 summarizes the design basis used in the simulation. The overall model, in its present form, is unable to predict changes in process conditions that would result from load changes on equipment of fixed sizes. The model can be used to simulate the steady-state operation of the plant, at or near design conditions, or to design other Stretford sulfur removal plants. 24 references, 12 tables.

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Numerical model of massive hydraulic fracture. Second annual report, September 1981-August 1982

Theoretical modeling of the expansion of hydraulic fractures has proceeded on three fronts: (i) blanket sand, no leakoff, fracture shape assumed, (ii) blanket sand, includes leakoff, fracture shape derived, (iii) lenticular sand. As a continuation of the last annual report, (1) assumes the fracture perimeter is an ellipse, then solves the governing equations (without leakoff) to obtain fracture height at the wellbore in two models, FL1 and FL2, for the case of a payzone bounded by two zones of higher (but equal) minimum in-situ stress. The two models describe the variation of minimum in-situ stress in the vertical direction differently. Subsequent modeling in (ii) indicates that the results here are a good approximation for the case in which the fracture shape and fluid flow profile are derived, rather than assumed. In a parameter study, the wellbore height and pressure are investigated as to the way they depend upon stress contrast between pay and bounding zones, elastic modulus of the formation (assumed the same in each zone), height of the payzone, and finally, fracture toughness in the bounding zones. To improve the accuracy of the modeling, in (ii) leakoff is included and the assumption of elliptical fracture shape is discarded. A complete, illustrative solution is given for fracture height, shape, and bottomhole pressure. The main limitation of the models in (i) and (ii) is that rate of height growth must be considerabl less than rate of length expansion. Finally, in (iii) some preliminary modeling of fracture expansion in lenticular gas sands is presented. 19 figures, 1 table.

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Physical beneficiation process and costs refinement for coal-water slurry manufacture. Quarterly technical progress report, October-December 1984

The following report presents the technical progress achieved during the first quarter. The completion of this contract entails engineering evaluation in conjunction with basic laboratory research to determine overall process improvements, associated cost savings and the effect of these savings on product price as they relate to the UCC Physical Beneficiation Process for coal-water slurry manufacture. The technical effort for this quarter has concentrated on two basic areas of concern as they relate to the above-mentioned process. First, an engineering evaluation was carried out to examine the critical areas of improvement in the existing UCC Research Corporation single-stage cleaning circuit (coarse coal, heavy media washer). When the plant runs for low ash coal product, at the specific gravity near 1.30, it was found that substantial product contamination resulted from magnetite carry over in the clean coal product. The reduction of the magnetite contamination would entail the application of more spray water to the clean coal drain and rinse screen, and the refinement of the existing dilute media handling system, to accept the increased quality of rinse water. It was also determined that a basic mechanical overhaul is needed on the washbox to ensure dependable operation during the future production of low-ash coal. The various cost elements involved with this renovation were determined by UCC personnel in the operational division. The second area of investigation was concerned with the laboratory evaluation of three separate source coals obtained from United Coal Company (UCC) and nearby mines to determine probable cleanability when using each seam of coal as a feed in the existing beneficiation process. Washability analyses were performed on each sample utilizing a specific gravity range from 1.25 to 1.50. 4 figures, 3 tables.

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Great Plains ASPEN model development:  development of a model for the density of solutions of aqueous electrolytes. Final topical report. [Extension of Debye-Huckel limiting law]

A new physical property model for the calculation of the density of solutions of aqueous electrolytes has been developed for the ASPEN process simulator as part of the simulation of the Great Plains Coal Gasification Plant. The model developed recently by Jay S. Dweck, Consultant, Inc. is an extension of the Debye-Huckel limiting law. The Debye-Huckel limiting law allows the predictions of the density of dilute solutions of dissolved salts by providing a relationship for the molar volume of the salt as a function of ion strength. The relationship is linear in the square root of ionic strength, with the slope dependent only upon the charges of the ions which constitute the salt. When combined with data for the infinite dilution molar volume of the salts, solution density can be calculated. The new model preserves the linear relationship with the square root of ionic strength, but introduces ion dependent parameters for the determination of the slope. The solution density is calculated in terms of the molar volumes of the individual ions, instead of a mixture of pseudo salts. Preliminary tests of the model have shown it to be far more accurate than the original limiting law, and applicable to more concentrated solutions (greater than 10 molar).

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Additive enhancement of pressure-hydrated lime for control of SO/sub 2//NO/sub x/ emissions

Control of SO/sub 2//NO/sub x/ emissions from low-rank coal combustion is investigated. This paper presents results from bench- and pilot-scal studies using pressure-hydrated lime and doped pressure-hydrated lime for the removal of SO/sub 2//NO/sub x/. These results indicate that greater utilization of sorbent may be achieved through pressure-hydration. Activation energies, reaction orders, and possible rate-limiting mechanisms for the sorbent-SO/sub 2/ reactions are also presented. The reaction of SO/sub 2/ with three sorbents formed by pressure hydration of quicklime was studied using thermogravimetric analysis and pilot-scale injection into a boiler. A semi-empirical pore-plugging model was used to describe the sulfation of dehydroxylated sorbents with good correlation of predicted and measured values of conversion. Activation energies of 26.8 to 49.0 KJ/mole were observed, the latter for a sorbent doped with sodium. Pilot-scale combustion were conducted firing natural gas. Injection temperature and baghouse temperature were nominally 1270/sup 0/K and 360/sup 0/ to 380/sup 0/K, respectively. Sorbent utilization values exceeding 70% at an alkali/SO/sub 2/ mole ratio of 1.0 have been observed. Simultaneous NO/sub x/ reduction of up to 20% has been observed. 14 references, 18 figures, 4 tables.

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Methods of chemical analysis for ionic constituents in synfuel wastewaters. Final report

The original thrust of this effort was towards improving ion chromatographic methods to detect all major ions. This technique was developed for the determination of chloride, nitrite, sulfite, phosphate, sulfate, nitrate, thiosulfate, and thiocyanate in a single run. A qualitative indication of total organic acids is also obtained. Sodium, ammoniacal-N, and K were determined separately by ion chromatography. Because the chloride peak occurred in a crowded portion of the ion chromatogram, an independent method was developed for chloride involving a digestion and titration. Measurements for pH and electrical conductivity were then made in order to check the accuracy of these individual measurements. However, it soon became clear that modified procedures for these measurements had to be developed in order to compensate for the high ionic strength of the synfuel samples. A computer program was developed to check the accuracy and completeness of the analyses by calculating ion balances, electrical conductivity, and total sulfur based on the individual determinations. Application of this program to a set of synfuel wastewaters indicated an acceptable agreement for most samples. However, it also became apparent that for some waters a major category of negative ions was missing, and for other samples the individual sulfur components did not account for the total sulfur found. For this reason additional efforts were directed towards determining the missing components. A gas chromatographic procedure involving a bonded-phase, carbowax capillary column was developed for the light organic acids. Efforts to develop a practical method for polysulfides, which were suspected as the missing sulfur component, were largely unsuccessful. 33 references, 14 figures, 12 tables.

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Kinetic behavior of solid particles in fluidized beds: Solid particle kinetic forces: Progress report for the period January 1-March 31, 1987

A tracer particle method has been developed and applied to investigate the effects of the parameters such as superficial gas velocity, fluidized particle size, and bed diameter on the kinetic forces prevailing in fluidized beds. The kinetic forces of fluidized particles become large with the increase of the fluidizing gas velocity in both bubbling and slugging flow regimes. The kinetic forces of fluidized particles also increase with larger sizes of fluidized particles. The bed diameter does not significantly affect the kinetic forces prevailing in fluidized beds if the bed height remains constant. The applicability of the Piezotron sensor for the measurement of kinetic forces was also investigated. The interpretation of the Piezotron sensor signal was hampered by the vibration of the fluidized column. However, the Piezotron sensor can still be used to evaluate the kinetic force distribution in the fluidized bed by inserting the sensor from the top of the fluidized bed (independent of column). The advantage of the Piezotron sensor is that a kinetic force distribution in the bed may be directly obtained. 2 refs., 10 figs.

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Development of molten carbonate fuel cell technology: Quarterly technical status report, January-March 1986

The program reported is divided into three tasks: Design; Component Development; and Verification Tests. The objective of Design is to identify a reference application for an internal reforming power plant and to develop a power plant conceptual design and detailed stack design. The objective of Component Development is to develop, fabricate, and test components to meet the Component Functional Requirements (CFRs). The objective of Verification Tests is to determine if the cell components have attained the CFR goals. 13 figs., 15 tabs. (FI)

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West Hackberry Strategic Petroleum Reserve site brine-disposal monitoring, Year I report. Volume III. Biological oceanography. Final report

The Department of Energy's Strategic Petroleum Reserve Program began discharging brine into the Gulf of Mexico from its West Hackberry site near Cameron, Louisiana in May 1981. The brine originates from underground salt domes being leached with water from the Intracoastal Waterway, making available vast underground storage caverns for crude oil. The effects of brine discharge on aquatic organisms are presented in this volume. The topics covered are: benthos; nekton; phytoplankton; zooplankton; and data management.

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Steam-oxygen combustion in asphalt ridge tar sand

The in situ forward combustion process was evaluated using both air and steam-oxygen injection. Bench scale tube reactor experiments were conducted on Asphalt Ridge (Utah) tar sand to study the effects of the nitrogen or steam component in the injected gas on the oil yield, product oil quality, and process efficiency. Total-injected-gas and oxygen fluxes of 40 and 8 scf/h-ft/sup 2/, respectively, were similar during both combustion experiments. Regardless of the injected gas composition, the oxygen consumption rapidly approached 100% and the combustion process became self-sustaining at ignition temperatures of about 650 to 750/sup 0/F (343 to 399/sup 0/C). This was because the partial pressure of oxygen was identical for both experiments. A carbonaceous fuel was burned after ignition and the combustion temperatures increased to 1200 to 1800/sup 0/F (649 to 982/sup 0/C). Steam injection reduced coke formation, and the steam-char reaction further reduced the coke available for combustion in the steam-oxygen experiment. These mechanisms resulted in reduced fuel availability, less oxygen consumption, increased combustion zone velocity, and a slightly greater oil yield for the steam-oxygen test. The oil yield for the steam-oxygen combustion test was 67 wt % of the initial bitumen, which was slightly greater than that from the air-only experiment. Other beneficial effects of steam versus nitrogen during the combustion process were improved heat transfer, reduced differential pressures, and greater heating value of the product gas for the steam-oxygen test. 11 refs., 2 figs., 7 tabs.

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Application of the Vertical-Tube Reactor to the treatment of selected oil-shale wastewaters

The project objective was to evaluate the use of the Vertical-Tube-Reactor process in the wet oxidation of wastewaters generated by two oil-shale processes. The Laboratory Batch Reactor (LBR), a small vessel of constant volume, was used to simulate the conditions a wastewater would experience in a full-scale Vertical Tube Reactor (VTR). The scope of work included three phases of laboratory, design, and cost-estimating effort. Phase I involved duplicate LBR runs at six temperature and time profiles and produced total chemical oxygen demand (TCOD), total suspended solids (TSS), and total organic carbon (TOC) reduction data for treatability curves. Computer modeling in Phase II yielded reactor configurations of various depths, maximum operating temperatures and reaction times for treating 2 mgd of 150T-SISR-R17 and 10 mgd of Geokinetics-R17. Cost estimates for the facility design and construction provided a basis for comparison of these various configurations. Each configuration was also analyzed for power consumption, equipment limitations and expected COD reductions. In Phase III a best VTR configuration for each wastewater was selected based on consideration of data in Phase II. Multiple LBR runs were performed at the design operating conditions for each VTR configuration selected and the results were compared with Phase I data and conclusions as to feasibility of treatment of the two wastewaters with the VTR process were drawn. Computer modeling and LBR results show it is technically feasible to treat each oil-shale wastewater with the proposed VTR configurations. Data on probable cost for these two VTR applications are provided.

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Wet carbonization of lump-size low-rank coals by a novel non-slurry approach. Progress report, November 1984-January 1985

The design of the wet-carbonization process research unit (PRU) continued during the current quarter. The PRU is designed to handle about 100 lb/h of as-received coal. The main reactor will be able to operate at a maximum temperature of 650/sup 0/F and a pressure of 2300 psig. Process flow and instrument diagrams for the system were completed. Equipment purchased during this quarter included the high-pressure feed and discharge screws, five pressure vessels and three pumps. Structural, electrical, and process control and data acquisition instrumentation bid packages have been prepared. Nine batch wet-carbonization tests were conducted during this quarter. Three coals were tested: two from North Dakota (lignites from Mercer and Oliver counties) and one from Montana (Rosebud subbituminous). The operating conditions of the tests covered a temperature range of 400/sup 0/ to 650/sup 0/F and a residence time range of 0 to 60 minutes. Preliminary results indicated that heating value enhancements of about 17% (ash-free basis) were achieved with Indian Head lignite wet carbonized at 650/sup 0/F for 60 minutes. A fourth coal, from the South Hallsville mine near Martin Lake, Texas, will be tested. Two tons of this Texas lignite are scheduled to be delivered in February. Tests to determine the weathering characteristics of these beneficiated coals are also being conducted. These include drop-shatter tests, equilibrium moisture content determinations, bulk and particle density measurements, and particle shrinkage determinations. Preliminary results indicate that increasing the wet-carbonization temperature from 400/sup 0/ to 550/sup 0/F decreased the equilibrium moisture content of the Indian head lignite from about 26 to 17 wt %. Liquid samples from these tests were collected for bioassay tests. 11 figs., 4 tabs.

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Reaction-induced temperature deviations during coal devolatilization in a heated grid

To gain further insight into the primary devolatilization process, particularly with respect to the tar yields, a new control circuit was designed to permit any heating rate from 800 C/sec to 4 x 10/sup 3/ C/sec to any final temperature in the 300 to 1100/sup 0/C range. With this circuit, the effects of sample characteristics on local heating of the grid were examined to assess the influence of devolatilization on programmed heating rates. The results clearly demonstrate that the devolatilization process has a considerable influence on the time-temperature history of the local screen in immediate contact with the sample. With respect to the coal particles, the direct implication is that the temperature path is the resultant of several components: the resistive heating of the grid, the physical properties of the samples, the devolatilization properties of the sample. Once the range of devolatilization temperatures of a particular coal is achieved, the primary devolatilization process appears to dominate the temperature-time trajectory. Because the heat requirement of the primary devolatilization affects the temperature trajectory of the coal particle, a real time model of primary coal devolatilization must necessarily include a consideration of this requirement. In addition, the data appears to indicate that the heat requirement varies with the rank characteristics of the coal. For a transient process such as rapid coal devolatilization the absolute magnitude of the heat required to vaporize the volatile components need not be large to result in a significant deviation from a programmed heating rate or a calculated heating rate of a nonvolatile particle. The results indicate that the tar release is closely coupled in time to the devolatilization-induced temperature deviations during primary devolatilization and the onset of the tar release significantly precedes the slower light hydrocarbon gas evolution.

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Great Plains ASPEN model development:  Phosam section. Final topical report

An ASPEN model has been developed of the PHOSAM Section, Section 4600, of the Great Plains Gasification Plant. The bases for this model are the process description given in Section 6.18 of the Great Plains Project Management Plan and the Lummus Phosam Schematic Process Flow Diagram, Dwg. No. SKD-7102-IM-O. The ASPEN model that has been developed contains the complete set of components that are assumed to be in the gasifier effluent. The model is primarily a flowsheet simulation that will give the material and energy balance and equipment duties for a given set of process conditions. The model is unable to predict fully changes in process conditions that would result from load changes on equipment of fixed sizes, such as a rating model would predict. The model can be used to simulate the steady-state operation of the plant at or near design conditions or to design other PHOSAM units. Because of the limited amount of process information that was available, several major process assumptions had to be made in the development of the flowsheet model. Patent literature was consulted to establish the ammonia concentration in the circulating fluid. Case studies were made with the ammonia content of the feed 25% higher and 25% lower than the base feed. Results of these runs show slightly lower recoveries of ammonia with less ammonia in the feed. As expected, the duties of the Stripper and Fractionator reboilers were higher with more ammonia in the feed. 63 references.

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