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论文类型：期刊论文

发表时间：2017-03-01

发表刊物：EDS Conference on Desalination for the Environment - Clean Water and Energy

收录刊物：SCIE、CPCI-S

卷号：69

页面范围：217-228

ISSN号：1944-3994

关键字：Desalination; Multi-effect evaporation; Parallel feed; Mixed feed

摘要：Horizontal-tube falling-film evaporator has been widely applied in the low-temperature multi-effect evaporation (LT-MEE) desalination system because of its unique advantages. Research shows that the spray density has a significant effect on the heat transfer effect of this kind of evaporator and it is closely related to the feed configuration. Therefore, this paper focused on the feed configurations suitable for the large-scale LT-MEE desalination plant based on a reasonable spray density, which include the parallel feed and mixed feed. Based on the mass and energy conservation equations, the corresponding mathematical models were established, which consider the thermodynamic losses including boiling point elevation (BPE), non-equilibrium allowance inside evaporators/condensers and distillate flashing boxes, and flow resistances from evaporation to condensation. Validity of the model was verified through comparison between the industrial data. The effects of heating steam temperature and number of effects on the performance parameters were investigated. The comparison of performance and scaling tendencies between various feed configurations was accomplished. Results show that the mixed feed system presents a better performance than the parallel feed systems, while scaling risk of the combination of backward and parallel feed configuration is the highest. This comparison illustrates the logic behind choosing each feed configuration.