褐煤水煤浆气化炉工艺烧嘴改造的模拟研究及应用

摘要

分析了国内首套褐煤水煤浆气化炉的运行情况,针对气化炉运行不稳定的情况,决定对工艺烧嘴进行改造,利用CFD软件进行了改造前后工艺烧嘴的冷态数值模拟.根据模拟计算结果,确定并实施了工艺烧嘴改造方案.改进后的工艺烧嘴在气化炉运行后,实际运行状态与数值模拟结果具有一致性,烧嘴气化燃烧火焰被拉长,轴向温度梯度减小,从而使得炉子拱顶及炉膛局部超温情况得到了改善,在同样氧煤比的情况下,渣口排渣更顺畅,但内喷嘴的使用寿命成为制约烧嘴长周期运行的重要因素.%The operating condition of the first set of the coal-water slurry gasifier of lignite in China was analyzed. With reference to unstable gasifier operation that required modification on process burner,utilized CFD software for cold state numerical simulation of process burner before and after the modification.According to the simulation results,the modification scheme was determined and implemented. After the modified process burner was used in the gasifier,the operation state was consistent with the simulation results. The combustion flame was elongated,and the axial temperature gradient was decreased, thus improving the local overheating of the vault and hearth of the furnace. The slag delivery at slag notch was smoother with the same ratio of oxygen to coal,but the service life of inner burner became an important factor for constraining the long-period operation of the burner.