Coal gasification model

Wen, C. Y. Chaung, T. Z. "Entrained-Bed Coal Gasification Modeling," 71st Annual AIChE Meeting, Miami, 1978. 

Schobert, H, Diehl, E., and Streeter, R. (1982) Current Studies in coal ash slag viscosity. Proceedings of Coal Gasification Modeling Workshop, DOE/METC, 82 (24), 415-431. 

Wen, C. and Chaung, T. (1979) Entrainment coal gasification modeling. Industrial Engineering Chemistry Process Design and Development, 18 (4), 684-695. 

This report presents a set of failure rate and time-to-restore data for typical components of a coal gasification combined cycle power generation unit. The data was used to examine the reliability and availability of a generic power generation unit using risk analysis models. 

M. Greenfeld described unique laboratory experiments designed to stimulate and understand the complex chemistry of in-situ coal gasification. Developed at the Alberta Research Council, the gasification simulator was heavily instrumented with calorimeters and gas chromatographs to determine the enthalpy, composition, and kinetics of formation of the product gases. Computer techniques were used to calculate mass and heat balances and to test kinetic models. 

Modelling studies for the moving bed were made at two gas compositions, a hydrogen rich composition containing 50% H2 and 20% CO with 10% H20 and 5% CO2, and a CO rich gas mixture containing 50% CO and 20% H2 with 5% H2O and 20% C02. Most results were obtained with the latter mixture, which is representative of gas produced from coal gasification, which is likely to have a major application for reduction processes in the future.Pellets of 8mm diameter were modelled unless otherwise indicated.Temperatures were varied from 873 to 1273K while gas flows and solid flow rates are typical of those used commercially. 

The Steady-State Permeation Model for Underground Coal Gasification... 

The steady-state permeation model of in situ coal gasification is presented in an expanded formulation which includes the following reactions combustion, water-gas, water-gas shift, Boudouard, methanation and devolatilization. The model predicts that substantial quantities of unconsumed char will be left in the wake of the burn front under certain conditions, and this result is in qualitative agreement with postburn studies of the Hanna UCG tests. The problems encountered in the numerical solution of the system equations are discussed. 

The last ten years have witnessed a number of extensive field tests of underground coal gasification (UCG) in the United States and Europe. Model development is essential to the proper understanding of these test results and to the planning of future experiments. This report will focus upon the steady-state "permeation" or "packed bed" model of in situ gasification (forward combustion mode). In this useful but idealistic model the coal bed is assumed to be uniformly permeable to reactant and product gases. 

Although the ASPEN process models can be put together to simulate many types of processes, it may still be necessary to use specialized or proprietary models. Such would be the case, perhaps, for a specific type of a coal gasification reactor. 

NITSCHKE Waste Heat Recovery System for Coal Gasification Limits of the Model... 

The model does not refer to any particular coal gasification process. However, in. view of the fact that the coal/water ratio is an essential parameter in the following calculations, it is obvious that in these cases it is the Texaco coal gasification process that was used as a basis. 

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