Feed and feed preheating effect on MED-TVC enhancement

Abstract EN

Rapid and significant growth of world installed capacity of Reverse Osmosis (RO) followed by Multi-Effect Distillation (MED) has taken place year after year.

Efforts are made to improve the system performance through increasing productivity and lowering specific power consumption by utilizing waste heat for seawater feed preheat.

The present work studies the importance of seawater preheating in MED by utilizing power plants condenser cooling water.

A steady state mathematical model for Multi-Effect Distillation combined with Thermal Vapor Compression (MED-TVC) system and the governing equations are solved using a computer program to evaluate the MED-TVC system performance.

The model validity is examined by data collected from two MED-TVC plants which showed good agreement.

Furthermore; the study results show that an increase of seawater feed temperature from 32 to 46 oC enhances the system productivity.

Also, it increases the Gain Output Ratio by 8.7%, and decreases the specific heat consumption and the heat transfer area by 9.6% and17.4% respectively.