奥里乳化油气流床气化过程的数值模拟研究

CFD simulation of Orimulsion gasification in an entrained-flow gasifier

采用欧拉-拉格朗日方法对奥里乳化油气流床气化过程进行数值模拟研究,对气化炉内的非均相反应过程采用颗粒表面化学反应模型描述,对均相反应过程采用考虑了湍流对均相反应影响的有限速率/涡耗散反应模型。研究结果表明,气化炉内靠近喷嘴区域反应剧烈,温度及组分变化明显,但在气化炉的后半段变化较小。同时考察了氧气当量比对气化炉性能的影响,高氧气当量比可以得到较高的炉内温度和碳转化率以及较低的CO和H2摩尔分数。

The Orimulsion gasification process in an entrained-flow gasifier is simulated with a Eulerian-Lagrangian method. The heterogenous reactions are described by the particle surface reaction model,while the homogenous reactions are modeled by the finite-rate/eddy-dissipation model, which considers the turbulence-chemistry interaction. The simulation results demonstrate that the chemical reactions are intense in the near-nozzle region, where the changes of temperature and species concentration are obvious. However, the temperature and species concentration only change slightly in the remaining part of the gasifier. In addition, higher oxygen/oil ratio leads to higher temperature and carbon conversion, but lower CO and H. concentration.