A study on gasification reactivity of pressurized two-stage entrained flow coal gasifier

CRIEPI and Mitsubishi Heavy Industry, Ltd. have developed a pressurized twostage entrained flow coal gasifier using a 2T/D bench scale gasifier. This type of gasifier was adopted for the 200T/D pilot plant project. The pilot plant test operation was started in March 1991 and was successfully finished in February 1996. Based on the results from the pilot plant, all Japanese electric power companies decided to construct the demonstration plant using the pressurized two-stage entrained flow type gasifier. In this type of coal gasifier, the product char is recycled to improve its efficiency. Using the experimental data of 2T/D gasifier, this report examines gasification characteristics such as product gas composition, cold gas efficiency and carbon conversion efficiency. Then, the effect of char recycle on gasifying efficiency and amount of product char is examined. Furthermore, per pass carbon conversion efficiency and fixed carbon conversion efficiency are evaluated.