What is considered a good UCG potential resource?
A wide variety of coals are amenable to the UCG process. Coal grades from lignite through to bituminous may be successfully gasified and in South Africa, both Sasol and Eskom has gasified bituminous coal. A great many factors are taken into account in selecting appropriate locations for UCG, including surface conditions, hydrogeology, lithology, coal quantity, and quality. The main criteria used for UCG are:
· Coal seam depth of +200 metres
· Coal thickness of more than 3 metres
· Ash content less than 60%
· Minimal discontinuities
· Isolation from valued aquifers.
The TUCG project conforms to all the minimum requirements with bituminous coal well over 300m deep and well isolated from surface aquifers and designed to stay 50m away from any detectable discontinuities / dykes.