Rapid Pyrolysis of Chinese Chaili Washing Middling Coal in a Down-flow Reactor and Combustion of Mixture of Char and Sand in an Up-flow Reactor

　To ascertain whether a coal pyrolysis-combustion combined system, which we propose, can be applied to washing waste coal or not, a Chinese Chaili washing middling coal was rapidly pyrolyzed in a down-flow reactor and a mixture of char and sand was burnt in an up-flow reactor. It was effectively pyrolyzed to recover gaseous and tarry products but blocked the reactor because of its caking properties. The chars produced were difficult to burn and generated more NOx and SOx in the exhaust gases. These suggest that some pretreatment of the coal is necessary to reduce the caking properties and some methods are needed to decrease NOx and SOx contents in the exhaust gases.