FOERFARANDE FOER SAMTIDIG ALSTRING AV BRAENNGAS OCH PROCESSVAERME UR KOLHALTIGA MATERIAL

摘要

In a process of simultaneously producing fuel gas and process heat from carbonaceous materials wherein the carbonaceous materials are gasified in a first fluidized bed stage and the combustible constituents left after the gasification are subsequently burnt in a second fluidized bed stage the throughput rate and the flexibility are increased in that the gasification is carried out at a pressure of up to 5 bars and a temperature of 800 DEG to 1100 DEG C. by a treatment with oxygen-containing gases in the presence of steam in a circulating fluidized bed and 40 to 80% of the carbon contained in the starting material are thus reacted. Sulfur compounds are removed from the resulting gas in a fluidized state at a temperature in the range from 800 DEG to 1000 DEG C. and the gas is then cooled and subjected to dust collection. The gasification residue together with the by-products which have become available in the purification of the gas, such as laden desulfurizing agent, dust and aqueous condensate, are fed to another circulating fluidized bed and the remaining combustible constituents are burnt there with an oxygen excess of 5 to 40%.