Fundamentals of coal gasification technology and its relevance to Botswana coal industry

Abstract

Coal is plentiful in many parts of the world but its combustion can create severe environmental and aesthetic problems.In the past three decades, the cost of crude oil and natural gas has been unstable and the reserves of these fuels are exhaustible. Other non-conventional energy resources, for example, solar, wind and tidal energy are only making a small contribution to the energy mix in few countries. Consequently, coal still has an important role to play to satisfy the energy demand, especially when it can be converted before combustion to other less environmentally objectionable forms, e.g. coal gas/producer gas. This paper describes the basic principles of coal gasification process and compares the performance of different gasifiers. The fundamentals of the raw gas cleaning methods are presented and experience to date of coal gasification in Botswana is discussed.It seems certain that coal gasification in tanderm with combined cycle power plant will be a principal technique for electricity generation in the next century. The paper recommends that Botswana takes necessary actions to gain maximum advantage from these developments.