AndreaBozzo/ceres-open-data-index huggingface dataset:
Thermal preconditioning of coal/water mixtures. Final report

Thermal preconditioning of coal/water mixtures is a process proposed for use with stationary gas turbine engines in which the CWM is heated before delivery to the combustor in order to accomplish the water vaporization and coal pyrolysis/devolatilization steps prior to injection. The process offers a number of potential advantages such as the ability to start the engine without the use of an auxiliary fuel system, the elimination of atomizing nozzles, increased flame stability for proper turndown, compatibility with NO/sub x/-control techniques such as rich-burn-quick quench combustors, and potentially faster char burnout. The objective of the program was to obtain information which will allow the feasibility of thermal preconditioning to be evaluated. The economics of the process and its impact on a combined cycle system have been addressed. The slurry heating and boiling processes have been studied and the relationships between fuel properties, temperature and residence time in the processing apparatus and the evolution of combustible gases have been measured. A special apparatus was designed and constructed for the experimental portion of the program. Results indicate that at temperatures above 900/sup 0/F significant devolatilization can be accomplished in residence times on the order of one second. A preliminary economic and performance analysis has been completed for the thermal preconditioning process. Four gas turbine power plant concepts incorporating thermal preconditioning of CWS have been investigated. These concepts differ from one another in the source of heat used for the preconditioning process. Heat paths have been defined and the relationships between the efficiencies and operating conditions of the various components on heat rate and plant output have been determined. The analysis indicates that increases in heat rate of less than 5% can be expected. 4 refs., 10 figs., 2 tabs.

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Reaction kinetics and physical mechanisms of ash agglomeration: Progress report for the period February 24-May 23, 1986

The long-term objective of the ash particle dynamics studies is to elucidate the physical conditions under which ash particles deposit or agglomerate. Of particular interest are the results of particle-particle and particle-wall collisions. The outcomes of such collisions will depend on ash particle composition, temperature, viscosity, surface tension, diameter, momentum, and impact parameters. The possible results of collisions include agglomeration, deposition, and shattering. To investigate the effects of these collisions, the DEM technique is being used. A cold-flow model of this device is being constructed and used to accelerate and aim the particles, measure their incoming and exiting angles, and observe the results of collisions. The modified dielectrophoretic manipulator (DEM) power supply has been tested. The new power supply operates at 800 (compared to the former 200) volts. It also distributes the voltage to the individual electrodes through a bank of relays that are manually controlled by a rotary multi-pole switch. This design will facilitate transition to computerized operation because the rotary switch can be readily replaced with a computer interface. The movement of particles during these tests was more reproducible than the movement during the lower voltage tests. Performance has been improved by removing the glass plates that prevent particles from contacting the electrodes. This places the particle in higher field gradient regions, but increases the probability of arcing. The unit cannot be used with conducting particles, but this poses no difficulty for ash experiments. This configuration can be tested with glass spheres. The presence of static charges or surface bonding is restricting the free movement of particles.

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Fluid dynamics of a fluidized bed packed with heat exchangers. Final report

Two fluidized bed facilities were built, and tests were conducted. Initially, a one-foot gas fired fluidized bed (GFFB) was built to study the bed dynamics and its interrelation with the heat transfer characteristics of immersed heat exchangers of different configurations. The GFFB, capable of achieving different gas velocity distributions in the bed with the help of a specially designed gas distributor, was operated to gain useful information on the influence of various operating parameters, such as the superficial gas velocity and its profile, the bed temperature (200/sup 0/F to 700/sup 0/F) and pressure (1 to 7 atm), and settled bed height (21''to 55''), on the bed expansion and heat transfer characteristics of vertical and horizontal tube bundles, and an inverted U-tube. Tests were also performed on an inverted U-tube with longitudinal fins, and two unfinned inverted U-tubes to study the effect of heat exchanger solidity (8% to 16%). Particle attrition studies were also performed at atmospheric pressure. A one-foot, coal-fired fluidized bed was also built and initial tests were performed. Typical heat transfer and particle attrition data were collected with a single verticle tube heat exchanger axially located in the bed. The behavior of deep and shallow beds, as observed in the GFFB, was confirmed. This report documents the tasks accomplished on the GFFB and the one-foot CFFB during the DOE contract period, February 1978 to August 1980.

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Detection/differentiation system development for deep source gases: Final report for Phase 1, October 1984-December 1985. [From different sources: sedimentary, abiogenic and subducted zones]

Phase I of this project was designed to collect and analyze hydrocarbon gases from three major sources: deep sedimentary basins, abiogenic, and subducted sediments. Results of the analytical scheme have been used to differentiate subduction zone gases from gases of deep sedimentary or mantle origins. One of the major diagnostic tests is the ratio /sup 3/He//sup 4/He, an unequivocal indicator of mantle contribution. Gases were collected and analyzed from the Permian Basin, West Texas, a major deep sedimentary basin, and Iceland, where mantle gases are released into the crust at a spreading ridge. Subduction zone gases were collected in two groups: geothermal gases from volcanic arcs in the Philippines, New Zealand and Alaska, and hydrocarbon production gases from forearc and backarc locations in Taiwan, New Zealand, Alaska, Barbados, Indonesia and the Philippines. Phase II of this project is designed to collect and analyze gases from the western margin of North America, an area of past and present subduction activity, and by applying the differentiation criteria established in Phase I, determine the origin of the gases. 138 refs., 41 figs., 4 tabs.

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Wet carbonization of lump-size low-rank coals by a novel non-slurry approach: Progress report for the period February-April 1986

Construction of the process research unit (PRU) was completed. Installation of the high-pressure boiler for the PRU was essentially completed, except for a few pieces of equipment. During boiler shake down tests, steam condensation shorted out the level probes causing the boiler to shut down. Several methods of remedying the problem were being investigated. During pressure testing of the PRU, several leaks were found. After they were repaired, the PRU was pressure tested successfully to over 2000 psig. Both the feed and discharge conveyors were calibrated with lump-size North Dakota Indianhead lignite. Calibration of instruments and testing of controls were initiated. The results of thermophilic batch anaerobic biogasification potential assays with filtered wet-carbonization product water showed a methane yield of 4.2 SCF/lb COD (chemical oxygen demand) added. This methane yield was achieved with an inoculum from an existing digester being fed product water from wet carbonization of peat. Bench-scale tests were continued in complete mixed, upflow, and attached-film digesters to evaluate performance and to determine the best reactor configuration for treating the product water. A new expanded-bed digester was installed.

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Dynamic analysis of slurry letdown valves at H-Coal pilot plant

Mechanical Technology Incorporated (MTI) is under contract to provide technical services for the improvement of performance of critical equipment required in the coal conversion process plants. A key service required in these plants is the level control of the effluent separator of the reactor vessel where coal conversion process takes place. This function is usually served by discharge of the liquid phase slurry in the separator through valves commonly called letdown valves. A number of technical problems have been experienced with the slurry letdown valves in the pilot plant operations. These include: excessive wear rate of critical valve components as a result of erosion, corrosion, and flashing; breakage of valve trim as a result of excessive flow induced vibration (fatigue) and/or sudden high bending load; breakage of valve stem as a result of excessive structure vibration (fatigue) of valve body, actuator, and associated piping; and coking formation in the valve eventually causing plugging. An approach to providing engineering data necessary for the understanding and eventual reduction/elimination of these problems is vibration measurement and structural analysis, including design analysis of structural damping characteristics. MTI has performed the following analysis for the understanding of the basic vibration phenomenona of the slurry letdown valves and made actual vibration measurements of the letdown valves presently under operation at the H-Coal pilot plant: lateral natural frequency and mode shape calculations of the valve stems; axial natural frequency calculations of the stems including the actuators; and valve body natural frequency calculations, including calculations for nearby piping and supports.

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Effects of coal-combustion effluent on pulmonary carcinogen metabolims. Quarterly progress report

This paper summarizes the direct effects of heavy metals in vitro on pulmonary, hepatic, and adrenal mixed function oxidizes including those involved in the metabolism of various carcinogens such as benzo(a)pyrene. Apparent enzyme activity decreased as a function of increasing incubation time for the assay. These observations further illustrate the relevance of the preincubation type experiments described in previous reports. Thus, duration of exposure to metals appears to be an important determinant of the effects on microsomal carcinogen metabolism. Since many heavy metals have extremely long half-lives in tissues in vitro, prolonged duration of exposure may contribute significantly to the toxicity of heavy metals.

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Gas separation using ion exchange membranes: Final report

The objectives of this project were twofold. The primary objective was to demonstrate the concept of using reactive ion exchange membranes (IEMs) containing organic amines for the separation of CO/sub 2/ and H/sub 2/S from coal gasification product gases. The potential advantage of this approach, known as facilitated transport, is to improve the selectivity of membrane separations without sacrificing high fluxes. A more fundamental objective was to investigate the mechanism of transport in ion exchange membranes. The facilitated transport of CO/sub 2/ and H/sub 2/S was studied using ion exchange membranes containing cations of ethylene diamine (EDA). Steady-state fluxes were measured for CO/sub 2/ and H/sub 2/S from single component gas streams, binary mixtures of CO/sub 2/ and H/sub 2/S with CH/sub 4/, CO/sub 2//H/sub 2/S binary mixtures, and ternary mixtures containing CO/sub 2//H/sub 2/S/CH/sub 4/. Fluxes were measured with and without EDA present as a function of feed gas composition. Diffusion coefficients were determined for H/sub 2/S, CO/sub 2/, and the EDA and gas complexes. A set of reaction and transport properties were collected from laboratory measurements and an extensive literature survey. The IEM separation factors compare very well with those for commercial membrane gas separation processes. Analytical models derived to predict the single component H/sub 2/S and CO/sub 2/ facilitation factors showed excellent agreement with experimental data. The importance of this project is that we have demonstrated experimentally that a reactive ion exchange membrane can be highly selective for CO/sub 2/ and H/sub 2/S over CH/sub 4/ and still have high fluxes. In addition, our understanding of the transport mechanisms involved has enabled us to simulate our experimental data theoretically, which is necessary for scaleup and design. 57 refs.

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Kinetic model development for low-rank coal liquefaction: Final technical report for the period March 15, 1983-October 31, 1986. [SEC-GS-MS]

The primary lesson learned was that the recycle solvents produced after 25 to 40 passes from the UNDERC process development unit (PDU) were exceedingly poor hydrogen donors and thus poor liquefaction solvents. Water at supercritical conditions in the presence of hydrogen sulfide was a good liquefaction solvent. The distillate yields were greater than those obtained from some experiments using the recycle solvents. The new analytical techniques developed for the analysis of coal-derived liquids by using SEC-GC-MS provide detailed information on chemical species in coal-derived liquids in a reasonably short analysis time. The availability of the data in terms of molecular size distributions and true boiling point diagrams should be of exceptional value to the designer of separation equipment. The SEC-GC-MS technique was fully automated for collecting the fractions from the SEC and analyzing these fractions by GC-MS for identification of components and qualitative analysis of the individual SEC fractions. We are unaware of any other technique that yields as much information on the composition of a coal liquid, and that presents it in such a usable form for the design, simulation and operation of reactors and downstream separation equipment. A major problem in the development of the mathematical model for the upflow tubular liquefaction reactor was the lack of good physical property data, transport property data, and correlations for bubble column reactors. A second problem was the lack of data on the composition of the two phases along the axis of the reactor. New mathematical techniques were developed to minimize the amount of computer time required in the estimation of parameters for the model from the experimental data. The distribution of the liquid and gas phases and the composition of the hydrogen and carbon monoxide in each phase can be predicted by use of equations of state. 36 refs., 12 figs., 4 tabs.

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Fluidized Bed Combustion Project, Grimethorpe Experimental Facility

The report presents the findings of an investigation into the freeboard cooler failure, in November 1981. The freeboard cooler was installed in the freeboard zone at the top of the combustor and the design intent was to operate so as to ensure the off-gas temperature did not exceed 900/sup 0/C. During Test Series One, the freeboard temperature never reached 900/sup 0/C, but the cooler was operated to reduce the exit flue gas temperature from the main heat exchanger to below the maximum allowable working temperature of the ductwork downstream of the exchanger. The cooler failed when several cracks appeared on bends in the air space between the combustor pressure shell and furnace water wall. A description of the cooler is provided along with details of its function, design, fabrication, commissioning and operation. The failure is described, and causes of failure are discussed. The report concludes that the failure occurred due to stress corrosion cracking.

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Anaerobic treatment of gasifier effluent: Final report. [Organic carbon]

Studies have been conducted to determine the biological treatability of coal gasification effluent for removal of organic carbon and ammonia. The treatment system consisted of an anaerobic activated carbon filter for organic carbon removal followed by a single stage nitrification system followed by a biological denitrification reactor. Dilute (approx.10%) wastewater was successfully treated over an extended period of time. However, after extended operation (approx. one year) inhibition of the biological system was encountered. This inhibition could be overcome by periodic replacement of a portion of the granular activated carbon contact media. Attempts to utilize the anaerobic system to treat solvent extracted ammonia stripped coal gasification effluent to remove substituted hydantoins was of limited success. Removals of 50% of the influent hydantoins were realized but only very small amounts of gas were produced. Apparently the primary removal mechanism was by adsorption on the granular activated carbon. Batch inhibition studies showed substituted pyridines as the primary inhibitory compounds in the raw wastewater. Carbon adsorption-solvent regeneration for hydantoin removal did not appear to be a viable treatment alternative due to low adsorption capacities and incomplete regeneration of the activated carbon. 37 refs., 63 figs., 23 tabs.

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Atmospheric fluidized-bed combustor design whose performance will significantly exceed conventional FBC operation performance. Final report

It is the goal of this project to bring forth a bench-scale design and test program to establish the merits of the circulating bed concept of atmospheric fluidized bed combustors (AFBC) and to show what the process development unit elements might be. The circulating fluid dynamics were modeled. From such a model the physical dimensions of a test system and the matrix for a test program can be established which will allow determination of parameters for scale-up evaluation of effectiveness and cost. This report presents an analysis of circulating bed boiler design methodology, alternative bench-scale designs for two coal feed levels (20 lbs/h and 80 lbs/h), including costs, and a test program. It is shown that the circulating bed concept has great merit for meeting DOE's advanced AFBC combustor criteria. A conceptual AFBC bench-scale design has been developed for an innovative AFBC system, specifically, a circulating bed boiler (CBB) for which two geometrically-similar designs, differing only in size, are presented.

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Expansion of high-temperature; high-pressure data set for coal gasification. Second quarterly report, December 28, 1984-March 28, 1985

A preliminary design was made of the pressurized version of the tube reactor. The design will be finalized and the reactor constructed during the third quarter. Approximately 25 trial pyrolysis tests with the Montana Rosebud 200 x 270 mesh have been made in the high pressure reactor (HPR). Operation has been very satisfactory with material balances of 95 to 105% and reproducibility of gas yields within  -10% for most experiments. An experiment was done at the same conditions used for a METC/AGC run (916/sup 0/C, 178 psig, 3.20s). The total yield of gas and the yields of gas and the yields of major gaseous species were similar. The yield of char was significantly lower in our experiment by an amount which corresponded to the amount of missing material. Much of the missing char was found in the upper part of the furnace and was presumably deposited by natural convection flows which are important at the low flow rates used for the long residence time experiments. We plan to transfer many of the lower temperature, long residence time runs to a second high pressure tube reactor with a very long hot zone to overcome this problem. The FT-IR diagnostic techniques were used to measure particle temperatures during pyrolysis of Montana Rosebud coal in the tube reactor. Additional experiments using the same technique were done in the tube reactor to measure optical properties of char prepared from the Montana Rosebud coal in the entrained flow reactor. During the course of these measurements, some problems with the FT-IR technique were encountered. Most of the quarter was spent identifying the source of these problems. The two major sources of error were identified as due to the presence of fines (primarily from particle breakup) and spurious reflection from particles back to the detector. These problems have been solved and previous measurements will be repeated where necessary. 2 refs., 2 figs., 2 tabs.

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Development and evaluation of the circular-grate coal gasifier concept. Phase 1. Final report

This report describes the results of Phase 1 of a program to develop and evaluate the circular-grate gasifier concept. For the gasification of coal, the circular grate potentially offers some very significant advantages over other equipment employed in the past. In Phase I, several process designs were evaluated and one was selected for detailed study. The use of the circular grate as a coal gasifier was explored and several potential advantages of such a unit in processing US coals were evaluated. A total of 13 experimental runs were performed in Phase 1. Six runs were static tests performed in a fixed-bed unit simulating a segment of the circular-grate gasifier. Seven runs were pilot tests performed in an actual small circular-grate gasifier, converted from an existing circular-hearth combustor at Midland-Ross Corporation in Toledo, Ohio. The results of the experimental runs showed that (1) the circular-grate gasifier can be used to produce a high-quality low-Btu gas, (2) it can be used to gasify highly caking coals, coals not normally possible to gasify satisfactorily in conventional fixed-bed gasifiers, (3) it can produce a product gas with extremely low dust, tar and oil levels, (4) it can gasify high-sulfur coals with most of the sulfur remaining in the ash and little appearing in the product gas, and (5) it can be controlled easily by changing air and steam rates and the speed of the grate. 11 figs., 7 tabs.

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Manual for applying fluidized bed combustion residue to agricultural lands

Atmospheric fluidized bed combustion (AFBC) is a process that reduces sulfur emissions from coal-fired electric-generating plants. The residue from this process is a mixture of alkaline oxides, calcium sulfate, and coal ash constituent. Since 1976, USDA/ARS has investigated the potential agriculture use of this residue. The investigations comprised an extensive series of laboratory, greenhouse, field plot, and animal feeding experiments. The best and safest use of AFBC residue in agriculture was as a substitute for agricultural lime. This report contains guidelines for applying AFBC residue to agricultural lands. 2 figs., 27 refs., 2 tabs.

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