An overview of underground coal gasification and its applicability for Turkish lignite

It is accepted that coal is going to maintain its significance as an energy source for longer time than oil and natural gas. Environmental concerns brought about the concept of clean coal technologies in the recent years. Coal gasification is one of the clean coal technologies. It may be applied on the surface for the mined coal or in-situ. Gasification of coal in-situ is called "Underground coal gasification" (UCG) and has several advantages over surface gasification and conventional mining. UCG provides low rank low calorific value coals a potential to contribute to the energy basket of a country. The majority of the Turkish coals are lignite. Therefore, underground coal gasification may enable diversification of energy sources of Turkey and may help decrease external dependency regarding the energy. In the literature no documentation covering detailed information about the UCG techniques, applications and discussing the applicability of these techniques to Turkish lignite is encountered. Hence, this study aims at matching a UCG technique to the most appropriate (Afsin Elbistan) lignite reserve in Turkey which may pioneer undertaking a pilot project regarding the area