A review on co-pyrolysis of coal and oil shale to produce coke

It has become the top priority for coking industry to rationally use and enlarge coking coal resources because of the shortage of the resources. This review focuses on the potential utilization of oil shale (OS) as a feedstock for coal-blending coking, in which the initial and basic step is pyrolysis. However, OS has a high ash content. If such OS is directly used for coal-blending coking, the coke product will not meet market demand. Therefore, this review firstly summarizes separation and beneficiation techniques for organic matter in OS, and provides an overview on coal and OS pyrolysis through several viewpoints (e.g., pyrolysis process, phenomena, and products). Then the exploratory studies on co-pyrolysis of coal with OS, including co-pyrolysis phenomena and process mechanism, are discussed. Finally, co-pyrolysis of different ranks of coals with OS in terms of coal-blending coking, where further research deserves to be performed, is suggested.