微波场薄膜蒸发器开发及液膜流动性能研究

Development of thin film evaporator for microwave field and study on flowing performance of liquid film

为有效利用微波实现混合物高效分离,依据微波场强化分离的特点开发了适用于微波场的薄膜蒸发分离装置,并分析了蒸发器内液膜流动特性。采用脉冲示踪法探究了进料流量和转速对停留时间的影响。结果表明,进料流量越大,蒸发器的平均停留时间越短,停留时间分布密度曲线均向左移,且分布密度峰值升高、曲线变窄。在小流量下,转速增大,平均停留时间也增大,而在较大流量下,转速对平均停留时间的影响不明显,且转速对分布密度的影响较弱。

To utilize microwave effectively to realize efficient separation of mixtures,a thin film evaporator suitable for microwave field is developed according to the characteristics of microwave-enhanced separation and the flowing performance of liquid film in the evaporator is analyzed.The influences of feeding flow rate and rotation speed on residence time are investigated through pulse-tracer method.It is shown that the larger the feeding flow rate,the shorter the average residence time（ART） in the evaporator,the residence time distribution（RTD） density curves will move to left and become narrower and the peak of distribution density get higher.Under smaller flow rate,ART increases with the increment of rotation speed,while the effect of rotation speed on ART is not obvious under larger flow rate.Meanwhile,the influence of rotation speed on RTD density is weaker,especially at low flow rate.