ENTRAINED-BED GASIFICATION - PRESENT STATE AND DEVELOPMENT TRENDS.

Entrained-bed gasification is characterized by cocurrent flow of coal and gasification agents. Coal dust of grain size below 0. 1 mm and a mixture of oxygen and steam in a ratio of up to 20:1 are used. The gasification temperature always exceeds the slag melting point. All types of coal can be employed including caking coals and char. The Koppers-Totzek process is the only entrained-bed process which has become established on an industrial scale. It operates under normal pressure. The Shell-Koppers, the Texaco and the Saarberg-Otto processes are now in the development stage. They involve coal gasification in an entrained bed under pressure.