Effect of several chlorides on combustion property of pulverized coal injection in blast furnace

In order to inhance the combustion rate of pulverized coal injection in the blast furnace, the combustion properties of pulverized coal injection in blast furnace were analyzed using chlorides (CaCl2, MgCl2, NaCl and FeCl3) as additives, and the influence of four kinds of chloride on coal combustion rate were obtained. The results show that the proper quantities of CaCl2, MgCl2, FeCl3 and NaCl can improve the combustion properties of pulverized coal injection in blast furnace respectively. When the content of CaCl2 and MgCl2 added is less than 1%, and FeCl3 content is less than 2%, the coal combustion rate improves with the increase of CaCl2, MgCl2 and FeCl3 content respectively; while increasing the additive contents continually, the coal combustion rate will all reduce. The coal combustion rate of pulverization coal injection increases when the content of NaCl added is increased. Compared with unburned pulverization coal produced from raw coal, the grains of unburned pulverization coal from coal with chloride additives become irregularity, and the particle size also diminish significantly. Generally speaking, the suitable proportion of CaCl2 and MgCl2 are 1% and FeCl3 2% respectively, and NaCl is less than 1%. FeCl3 should be chosen firstly as chloride additive for improving the combustion property of pulverization coal injection, CaCl2 and MgCl2 are the second choice, and NaCl is the last. ©, 2014, Meitan Xuebao/Journal of the China Coal Society. All right reserved.