Numerical and experimental study of strata behavior and land subsidence in an underground coal gasification project

N. N. Sirdesai, R. Singh, T. N. Singh, P. G. Ranjith

Research output: Chapter in Book/Report/Conference proceedingConference PaperOther

16 Citations (Scopus)

Abstract

Underground Coal Gasification, with enhanced knowledge of hydrogeological, geomechanical and environmental aspects, can be an alternative technique to exploit the existing unmineable reserves of coal. During the gasification process, petro-physical and geomechanical properties undergo a drastic change due to heating to elevated temperatures. These changes, caused due to the thermal anisotropy of various minerals, result in the generation of thermal stresses; thereby developing new fracture pattern. These fractures cause the overhead rock strata to cave and fill the gasification chamber thereby causing subsidence. The degree of subsidence, change in fluid transport and geomechanical properties of the rock strata, in and around the subsidence zone, can affect the groundwater flow. This study aims to predict the thermo-geomechanical response of the strata during UCG. Petro-physical and geomechanical properties are incorporated in the numerical modelling software COMSOL Multiphysics and an analytical strength model is developed to validate and further study the mechanical response and heat conduction of the host rock around the gasification chamber. Once the problems are investigated and solved, the enhanced efficiency and the economic exploitation of gasification process would help meet country's energy demand.

Original languageEnglish
Title of host publicationProceedings of the International Association of Hydrological Sciences
Pages455-462
Number of pages8
Volume372
DOIs
Publication statusPublished - 12 Nov 2015
Event International Symposium on Land Subsidence 2015 - Nagoya, Japan
Duration: 15 Nov 201519 Nov 2015
Conference number: 9th

Publication series

NameProceedings of the International Association of Hydrological Sciences
ISSN (Print)2199-8981

Conference

Conference International Symposium on Land Subsidence 2015
Abbreviated titleNISOLS 2015
CountryJapan
CityNagoya
Period15/11/1519/11/15

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