Investigation of Chinese oil shale resources comprehensive utilization performance

A novel comprehensive utilization system of oil shale involving retort subsystem, combustion subsystem, electricity generation and ash processing subsystem is recommended for Huadian oil shale. To ensure the thermal balance and stable operation of the whole system, part of non-condensable gases from retort process, as auxiliary fuel, are introduced into a combustor connected before the CFB furnace. The system performance is simulated using ASPEN software tool in this paper. The influence of retorting temperature, residence time, temperature and pressure of the CFB furnace, content of oil shale for combustion, content of non-condensable gases for combustion on the system performance are discussed. In order to explore advantages of this system, a retort system and a combustion system are investigated. The results show that increasing retorting temperature, residence time, pressure of CFB furnace and content of non-condensable gases for combustion has positive significant effect on improving the total profit and the output energy efficient of the comprehensive utilization system. The solid heat carrier technology is more adaptable for this system. Compared with other utilization modes for oil shale, the comprehensive utilization system has higher utilization efficiency of oil shale resources, more diversified products, lower pollutants emission and higher total profit.