ABSTRACT Multistage membrane distillation units connected in series for water desalination is considered. The influence of the number of stages and the module length per stage on the overall economics is investigated via simulations using a validated model. Depending on the degree of feed salinity, a suboptimal condition occurs at a structure size of 40 ~ 35 stages with an average module length of 15 ~ 12 m. The corresponding specific operating and fixed costs are $8 ~ 12.5/m3 and $0.97~−.8/m3, respectively. For a high salinity feed, the optimum specific operating cost increases due to reduced mass production. Membrane porosity and thickness showed a pronounced effect on cascade structure economics. The specific operating cost can be further reduced by an average of 60% using permeate heat recovery systems.

中文翻译：

---

多级膜蒸馏配置中模块长度和级数的优化

摘要 考虑串联连接用于海水淡化的多级膜蒸馏装置。级数和每级模块长度对整体经济性的影响通过使用验证模型的模拟进行研究。根据进料盐度的不同，在平均模块长度为 15～12 m 的结构尺寸为 40～35 级时出现次优条件。相应的特定运营成本和固定成本分别为 $8~12.5/m3 和 $0.97~-.8/m3。对于高盐度饲料，由于批量生产的减少，最佳的特定操作成本会增加。膜孔隙率和厚度对级联结构的经济性有显着影响。使用渗透热回收系统可将特定运营成本平均进一步降低 60%。