减压膜蒸馏法脱除水溶液中氨——传质系数研究

Ammonia Removal from Aqueous Solutions by Vacuum Membrane Distillation——Study on Mass Transfer Coefficient

推导了传质系数计算公式 ,讨论了各种影响因素与传质系数的关系 ,并对传质数学模型计算的脱氨值与实验测定值进行了比较。结果表明 ,起始浓度与传质系数无关 ;随着料液温度的增加 ,传质系数呈指数增大 ;料液流量增加 ,传质系数增大 ,特别在流体处于层流区时更为明显 ;在一定范围内 ,减压侧压力对传质系数基本无影响 ;

The relationship between technological conditions and mass transfer coefficient was discussed, and ammonia removal values between the experimentally measured and the calculated by mathematical model were compared. The results show that, there was no influence of initial concentration on mass transfer coefficient; increasing feed temperature increased mass transfer coefficient exponentially; increasing feed flow rate increased mass transfer coefficient, especially in laminar flow regime; At a certain range of pressure in the permeate side, there was no influence of pressure in the permeate side on mass transfer coefficient; Ammonia removal values between the experimentally measured and the calculated agreed with each other satisfactorily.