New technology of high concentration coal water slurry (CWS) preparation technology from low rank coals and lignite for CWS gasification

摘要

A new technology for preparation of coal water slurry (CWS) with high concentrationfrom low rank coals and lignite by dry method with optimum particle size distribution （PSD）wasdeveloped based on two principals: high bulk density with optimum PSD and conversion ofinterior bound water into free water by grounding coal to less than several ?m and developing newadditive. The coal loading in CWS using the new technology can reach 68% for Shenmu coal and58% for lignite about 10% higher in comparison with conventional method, which will greatlyincrease the economic and social benefits. The recent progress using this new technology isintroduced in this paper. The dry mill with capacity of 80 t coal/h has been developed. The majoradvantage is that the lignite with water content of less than 40% can be directly fed to the millwithout pre-dry. Various low rank coals and lignite are tested for several coal chemical plants. Thereformation of the existed plant and the technology for construction of new plant are alsointroduced.