Numerical Simulation On The Swirl-flow Melting Furnace In MSW Gasification And Melting System

In China, municipal solid waste (MSW) has become a serious environmental problem to block the sustainable development of the society. The traditional technologies to dispose MSW have been proven having many shortcomings in harmlessness, especially the problems of the release of heavy metals and dioxins by incineration technology. MSW gasification & melting technology is a new technology for waste treatment. It combines MSW gasification and fly ash melting, having several outstanding advantages, such as strict pollution control, notice volume reduction, and effective resource utilization. Thus, MSW fluidized-bed gasification and swirl-flow melting technology has been proposed and developed. This paper is mainly on numerical simulation of gas-particle two-phase flow of swirl-flow melting furnace for designing and optimizing the swirl-flow melting furnace of 200 t/d's system.Based on the review on the gas-particle two-phase models, the merits and drawbacks of various models were compared and analyzed. According to the characteristics of swirl-flow melting furnace, suitable gas turbulence model, gas-particle two-phase flow model and discrete phase model were chosen. Analysis of the stresses on particles was made.In order to design the swirl-flow melting furnace of the MSW fluidized-bed gasification & melting system with a capacity of 200 t /d, a preliminary design was proposed, the parameters of traditional coal-combustion cyclone furnace used for reference. Numerical simulation was carried out to predict temperature field, pressure field, flow field and particles' trajectories in the swirl-flow melting furnace. The effects of different structural parameters and operating conditions on gas combustion and slag particles capture were researched and analyzed.For increasing the efficiency of slag capture, the design parameters of swirl-flow melting furnace were optimized. By changing parameters, the study emphasized on smaller particles capture. According to numerical simulation results, considering...