吸收膜蒸馏淡化海水研究

STUDY ON SEAWATER DESALINATION BY OSMOTIC DISTILLATION

针对吸收膜蒸馏(OD)系统的进料液和吸收液的温度非常接近甚至相同,其传质过程无相变热损失,有可能实现能耗较低的膜蒸馏过程这一设想,尝试开展OD法海水淡化研究。以葡萄糖水溶液为吸收液,考察了温度、料液及吸收液流速、吸收液含量等参数对OD过程的影响。结果表明,随温度的升高,膜通量增大明显;随吸收液和料液流速的增大,膜通量增大,且料液浓缩倍数较小、含量较低时,吸收液流速相对料液流速,对通量的影响更大,反之,料液浓缩倍数较大、含量较高时,料液流速的影响更大;随着吸收液含量的增大,膜通量也相应增大。试验过程中未发生疏水膜的亲水化渗漏现象。

Due to the temperatures between the both sides of the membrane are quite close or even the same in osmotic distillation system, there is no phase inversion heat loss in this process. It is possible to achieve a lower energy consumption of membrane distillation process. Therefore, the study on seawater desalination by osmotic distillation is carried out. The osmotic distillation experiments were performed with the seawater as feed solution and glucose solution as extractant in seawater desalination. The effect of operating conditions, such as temperature, feed and extractant flow velocities, and extractant concentration, onosmotic distillation flux were investigated. It was observed that increasing temperature improves the osmotic distillation flux significantly. Feed and extractant flow velocities also have obvious effect on osmotic distillation flux. At lower feed concentration range, the extractant velocity is more important than the feed velocity, while it is the opposite at higher feed concentration range. The osmotic distillation flux increased as increasing the extractant concentration. Hydrophilic leakage of the hydrophobic membrane did not occur in the experimental process.