Abstract

The underground coal gasification (UCG) has a potential for converting the world’s coal resources into energy, liquid fuels and chemicals. The UCG process involves the injection of steam and air or oxygen into an underground coal seam and igniting and burning of coal in-situ to produce the combustible gas. Previous studies showed that many criteria affect site selection of UCG. The criteria include coal seam properties, faulting, discontinuity, properties of hanging wall and footwall of coal seam and hydrogeological regime. In this paper, considering proper UCG site selection criteria, coal seam was ranked and selected for the UCG based on the controlled retraction injection point (CRIP) configuration in Mazino coal deposit. The result of this investigation showed that the M2 coal seam has great advantage (considering the seam thickness and reservoir) related to the other coal seams for the gasification by CRIP configuration.

Key words: Underground coal gasification (UCG), site selection criteria, Tabas coalfield, clean energy.