Effect of Hydro-Thermal Treatment with CaO Addition on the Coking Properties of Shengfu Coal
Shengfu (SF) coal was hydro-thermally treated with and without CaO addition at different temperatures and the crucible coking determinations were carried out to evaluate the effects. The results show that hydro-thermal treatment can obviously increase the micro-strength index (MSI) of the coke and particle coke strength after reaction (PSR), and decrease particle coke reactivity index (PRI), which are beneficial for metallurgical coke to increase the gas permeability in blast furnace. Addition of CaO during hydro-thermal treatment at 150-250°C greatly promotes the effects of hydro-thermal treatment. However, hydro-thermal treatment at 300°C with CaO results in dramatic decrease in MSI and PSR due to the enhanced hydrolysis reactions at this temperature by CaO to form strong cross-linking in the treated coal.