A model for cavity growth and resource recovery during underground coal gasification

Journal Article · Sat Dec 31 23:00:00 EST 1988 · In Situ; (USA)

OSTI ID:5633832

Britten, J A; Thorsness, C B ^[1]

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1. Lawrence Livermore National Lab., CA (USA)

A model describing cavity growth and gas production during underground coal gasification (UCG) has been developed. It is applicable to UCG of shrinking coals in which oxidant injection is maintained at a fixed point low in the coal seam. It is based on a few fundamental assumptions; namely that the cavity is axisymmetric about the injection point, all resistance to injected gas flow is through ash and overburden rubble that accumulates on the cavity floor, thermal radiation dominates in the well-mixed void space, and the coal and overburden spall or rubblize on a small scale du to parameterized thermal effects. The model calculates water influx from the coal aquifer, flow dispersion trough the rubble piles, radiant and convective heat transfer, gas/solid, gas-phase and simple pyrolysis reactions to calculate, through mass and energy balances, recession rates of cavity surfaces and generation rates of major product species. Model predictions are shown to compare very well with process and geometrical data from two UCG field tests, and the model is used to simulate UCG Of other coals of UCG interest.

• OSTI ID: 5633832
• Journal Information: In Situ; (USA), Journal Name: In Situ; (USA) Vol. 13:1; ISSN 0019-3267; ISSN ISOMD
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
010404* -- Coal
Lignite
& Peat-- Gasification
012030 -- Coal
Lignite
& Peat-- Underground Mining-- (1987-)
COAL DEPOSITS
COAL GASIFICATION
COAL SEAMS
DATA ANALYSIS
ENERGY TRANSFER
ENHANCED RECOVERY
FLUID INJECTION
GAS INJECTION
GASIFICATION
GEOLOGIC DEPOSITS
GEOMETRY
HEAT TRANSFER
MATHEMATICAL MODELS
MATHEMATICS
MINERAL RESOURCES
MINING
RECOVERY
RESOURCES
THERMAL RECOVERY
THERMOCHEMICAL PROCESSES
UNDERGROUND MINING