Fluid flow characteristics and coal gasification performance under various injection patterns in a Shell gasifier

Abstract

Shell gasifiers utilize four opposing burners to generate a fluid flow that maintains symmetrical rotational motion, which is known as symmetrical swirl flow. This flow pattern intensifies the interaction and mixing between coal particles and gas, thereby facilitating heat transfer, mass transfer, and reaction efficiency. However, the burner injection fluctuations may occur due to the operational troubles. Herein, in-depth insights into fluid flow characteristics and coal gasification performance in a Shell gasifier were studied via simulation. Three types of injection patterns were investigated: the normal operating condition (NOC) and two abnormal operating conditions including a pair of burners with halving feedstock (AOC1) and complete blockage (AOC2). Typical fluid flow patterns were elucidated from the evolution of coal particle motion. Compared to the axisymmetric swirling flow in NOC, the swirling flow was out of balance and extended outward to impact wall in AOCs. The temperature within gasifier was illuminated by analyzing the inside-out transition of isothermal surface. The syngas production in NOC was averagely lower by 37.32 % than that in AOC2.