Thermal brown coal dust processing - in two cyclone stages recycling part of gas mixture

摘要

Brown coal dust and other low-grade fuel is processed thermally in a first heating stage at 500-800 degrees C for 1 sec, and a second heating stage by a gaseous heat carriers at 600-900 degrees C. The mixture of steam and gas from the second stage is recycled to the first stage together with a part of a solid fuel produced, if necessary, with an additional heat input. Low-grade fuel is thus converted into a high-quality gas with a better yield and for the same energy consumption, compared with conventional processes.