Abstract:

Polyvinylidene fluoride (PVDF) hollow fiber membrane is used as membrane material, NaCl solutions with concentrations of 5%, 15% and 25% are treated by direct contact membrane distillation. Orthogonal experiment is used to optimize the operation conditions, and the result show that value of the permeate flux (J) could achieve maximum value of 12.599 kg/(m²·h) when the inlet temperature of liquid side (T₁) is 80℃, inlet temperature of osmotic side (T₃) is 20℃, and flow rate (Q) is 100 L/h. Gained output ratio (GOR) could be 13.775 when T₁ is 80℃, T₃ is 35℃ and Q is 40 L/h. The salt rejection ratio all is more than 99.9%. The result of single factor experiment show that J is raised with the increase of T₁ and Q, but decreased with the increase of T₃. GOR is increased with the increase of T₁ and T₃, but decreased with the increase of the Q. The research indicate that membrane distillation technology has a good applied prospect of treat saline solution.

摘要：

采用聚偏氟乙烯（PVDF）中空纤维膜作为膜材料，利用直接接触式膜蒸馏法处理质量分数分别为5%、15%和25%的NaCl溶液；使用正交实验方法对操作条件进行优化设计，研究表明当料液侧入口温度T₁为80℃，渗透液侧入口温度T₃为20℃，流量100 L/h时膜通量最大，可达12.599 kg/（m²·h）；当料液侧入口温度T₁为80℃，渗透液侧入口温度T₃为35℃，流量Q为40 L/h时造水比最高，可达13.775，截留率均可达到99.9%以上；单因素实验结果表明膜通量随着T₁和Q的增大而增加，随着T₃的升高而降低；造水比随着T₁、T₃的升高而增加，随着Q的增加而降低。研究表明膜蒸馏技术处理含盐溶液具有很好的应用前景。