Process Modeling, Simulation and Optimisation of Different Configurations of Multi-Effect Distillation Plant

This research is focused on process modeling, simulation and optimization of various configurations of multi effect distillation desalination plants on Aspen Hysys v8.8 to get efficient performance ratio. For demonstration purpose multi effect distillation-forward, multi effect distillation parallel and multi effect distillation- double pre heating was chosen. For simulation purpose, the number of effects in multi effect was restricted to three. I conducted optimization of the production of triple effect distillation considering various possibilities for the optimal production of distilled water i.e. effect of mass flow rate of input steam (Case A) and effect of temperature of input steam on the mass flow rate of distillate (Case B) was obtained on Aspen Hysys V8.8. Then for each of the above two cases performance ratio was generated and the maximum mass flow rate of distillate was obtained. Within three different configurations of Multi- Effect Distillation (MED) it was concluded that highest value of performance ratio was obtained when the temperature of input steam was 60c for sea water having 0.05 mass fraction NaCl and 0.95 mass faction 1120. The maximum amount of distillate will be obtained when the maximum permissible mass flow rate of steam was supplied but for Multi-Effect Distillation- forward feed for both the cases of varying mass flow rate of input steam and by varying the temperature of input steam the mass flow rate of product obtained remains same. For given conditions of input feed water i.e. mass flow rate of 18000kg/h, 35c input temperature, zero vapour fraction and for triple effect distillation, MED double pre heating Case B has the highest value of performance among all configurations. Maximum amount of distillate was achieved in configuration of MED parallel case A and MED double pre heating case B for which the supplied steam was at temperature of 110c. Now depending upon the objective of the industry a compromise is to be done between maximum amount of distillate and the efficient performance ratio to feed its utilities.