大规模粉煤气化炉水汽系统水动力模拟研究

Hydrodynamic simulation of steam-water system of large scale pulverized coal gasifier

为评价气化炉水汽系统的水动力安全或优化水汽系统的操作参数,设计了循环系统校核计算迭代流程,开发了适用于干煤粉气流床气化系统的水动力计算软件。采用CFD数值模拟和水动力计算软件相结合的方法,对耗煤量为2 200 t/d的干煤粉气流床气化炉水汽系统进行了研究,获得了大型气流床气化炉烧嘴支撑、水冷壁、排渣口和热裙壁水汽系统的进出口水温、压力、水量和水速等参数值。在此工况下,各水路的热负荷均低于临界热负荷,不会发生水管烧坏的风险。研究结果表明,气化炉水汽系统中不同水路的水量相差较大,如热裙壁的水量为3.211 5 kg/s,水冷壁的水量为91.105 6 kg/s。气化炉汽水系统各支路水速变化不大,变化范围是3.044 4~4.261 0 m/s。气化炉水汽系统各水路入口压力几乎相同,约为5.6 MPa,出口压力约为5.5 MPa。

It is important to evaluate steam-water system's hydrodynamic security and optimize the operational parameters of steam-water system of gasifier. An iterative flow chart of circulatory system checking calculation was designed. A hydrodynamic calculation software was developed for entrained flow pulverized coal gasification system. The CFD and hydrodynamic calculation software were used to investigate the steam-water system hydrodynamic of entrained flow pulverized coal gasifier which consumed dry pulverized coal 2200 t/d. The hydrodynamic parameters of burner support, cooling wall, slag discharged, heat skirt membrane of large entrained flow gasifier were obtained, respectively. Under the operation, the cooling wall could not burn out. The water mass flow of heat skirt membrane and cooling wall are 3.2115 kg/s and 91.1056 kg/s, respectively. The variety of water mass flow in different water paths is big. The range of water velocity is 3.0444-4.2610 m/s and the change is small. The pressure of inlet and outlet of gasifier's steam-water system are 5.6 MPa and 5.5 MPa, respectively. © 2015, China Coal Society. All right reserved.