Numerical simulation of flow and gasification characteristics with different swirl vane angles in a 2000 t/d GSP gasifier

摘要

A 2000 t/d GSP entrained flow pulverized coal gasifier suffered problems of high temperature corrosion to burners and cooling screens. The simulation of the flow and gasification characteristics was conducted to find the cause. The cold-flow experiments in a 1:3.5 scale model gasifier and mimic simulation were carried out to verify the numerical methods. Then through the full-scale thermal simulation, the simulation results showed favorable agreement with the previous results in the literatures. The combustion reaction for pulverized coal occurred mainly in the jet region, while the coal gasification reaction was dominant in the gasification chamber. As the swirl vane angle increased from 0 degrees to 36 degrees, the expansion angle of the flame increased gradually, and the radial distance from the jet region to the wall decreased; the hot gas in the jet region was more concentrated and close to the burner. These aggravated the high temperature corrosion to the cooling screen and the burner. When the swirl vane angle was 26 degrees, the molar fraction of the syngas (CO + H-2) and carbon conversion rate reached the peak values of 96.2% and 98.1%, respectively.