摘要
煤气化是煤化工的先导技术,粉煤气化以其高碳转化率和高冷煤气效率日益得到重视。通过物理建模,建立起粉煤气化的数学模型,运用欧拉一拉格朗日方法分析气化炉冷态流场分布特性;运用非预混方法分析气化炉热态运行条件下温度分布和煤气成分变化规律。通过对模型的数值分析,冷态条件下颗粒相和连续相之间的最大速度比约为0.828;煤粉颗粒在旋转力矩作用下螺旋上升,颗粒在炉内停留时间增大;热态条件下湍流火焰中心存在"黑区",火焰外锥面对应氧浓度梯度变化最大的表面,燃烧剧烈、温度较高。热态条件下数值模拟得到生成气成分分布和气化炉设计工况基本吻合。
Coat gasification was the forerunner technology of coal chemical industry, and now pulverized coal gasification had been widely utilized due to its higher carbon conversion and cold gas efficiency. A mathematical model was established to predict the characteristic of fluid flow of pulverized coal gasifier. In this model, Eulerian and Laglange model were performed to analyse the characteristics of granule phase flow and continuous phase flow in cold condition ,and non-premixed combustion model was employed to analyse the hot condition of gasifier. Results show that the velocity ratio to particle phase and continues phase is 0.828 in cold condition; axial torque make particles spiral ascent, and prolong the residence time. In hot condition, there are some "low temperature area" in the middle of turbulent flame. The maximum concentration gradient of oxygen occurs in the flame male cone,where the temperature are higher than other areas. The coal gas distribution calculated by numerical simulation are in accord with design value.
出处
《中国电机工程学报》
EI
CSCD
北大核心
2007年第20期30-35,共6页
Proceedings of the CSEE
基金
国家重点基础研究发展计划(973计划:2004CB217701)~~
关键词
气化
冷热态运行
颗粒
渣层
gasification
cold and hot condition
particle
slag