Thermodynamic analysis of feed water pre-heaters in multiple effect distillation systems

The purpose of this article is to investigate the influence of using feed water pre-heaters in multiple effect distillation systems with thermal vapor compression (MED-TVC). By using these heat exchangers, temperature difference between feed water and steam in each effect would be constant. In this way, the required energy for preheating the feed water will decrease and the feed water evaporates as soon as it enters the effect. In this article, it is shown preheating the feed water has a great influence on decreasing the energy consumption of MED-TVC distillation systems. The influence of different configurations of feed water preheating on energy consumption of MED-TVC process is investigated as well. Results show that the energy consumption will be minimum if the pre-heaters increase the feed water temperature in such a way that their temperature difference is equal to that of effects.