摘要
基于直接热解氯化稀土溶液制备稀土氧化物技术,设计一种新型射流热解反应器,并采用CFD方法对反应器内压力、速度等流体动力学特性进行了数值模拟。结果表明:射流热解反应器喉管处自主产生的动压(p)与燃气的进口速度(v)呈二次函数关系(p=0.06v^2+0.23v-4.49)。欲使氯化稀土溶液热解反应充分利用燃料燃烧所产生的热量,需在进料口施加一定的压力,此压力与燃料的进口速度呈二次函数关系(p=v^2+3v-4.27)。进料口的直径增加到原来的1.25和1.5倍,稀土氧化物的吸入量分别增加了30%和60%以上。整个反应器内流体流动主要受燃料的入口速度影响,且在喉管附近速度形成波峰,随物料加入速度急剧下降,到射流反应器末端速度趋于平缓。
Rare earth oxide was prepared via direct pyrolysis of rare earth chloride solution. Based on this technique, a new-type jet-flow pyrolysis reactor was designed, and then the fluid dynamics (pressure and velocity) inside the reactor was numerically simulated using a computational fluid dynamics method. The self-produced pressure (p) and the fuel inlet velocity (v) satisfied a quadratic function,p=0.06v2+0.23v?4.49. To fully utilize the combustion-generated heat in pyrolysis of rare earth chloride, an appropriate external pressure p=v2+3v?4.27 should be imposed at the feed inlet. The 1.25- and 1.5-fold increase of feed inlet diameter resulted in decline of adsorption dynamic pressure, but the intake of rare earth chloride increased by more than 30% and 60%, respectively. The fluid flow in the reactor was affected by the feeding rate; the fluid flow peaked near the throat of venturi and gradually smoothed down at the jet-flow reactor’s terminal along with the sharp decline of feeding rate.
基金
Projects(51204040,U1202274)supported by the National Natural Science Foundation of China
Projects(2010AA03A405,2102AA062303)supported by the National High-tech Research and Development Program of China
Project(2012BAE01B02)supported by the National Science and Technology Support Program of China
Project(N130702001)supported by the Fundamental Research Funds for the Central Universities,China
关键词
数值模拟
氯化稀土
射流
热解反应器
numerical simulation
rare earth chloride
jet-flow
pyrolysis reactor