Improvement of multi-stage flash seawater desalination system

According to the parameter characteristics of electricity-water cogeneration, a modified desalination system (Enhanced Multi-Stage Flash, MSF-E) was proposed which considered the advantages of multi-stage flash system (MSF) and low temperature multiple effect desalination system (LT-MED). The main idea is that the 0.12-0.25 MPa steam extracting form steam turbine is used as heat source, a part of flash vapor in flash room is taken into next one to heat the recycling brine, and the system makeup water is supplied by cooling seawater of thermal power unit instead of seawater. The performance calculating model of MSF-E was set up and the influences of parameter on system performance were analyzed. The calculation and research results show that the performance ratio can increase by 42.6% and the brine density in every flash stage can decrease by 22.1% averagely in comparison with conventional MSF system when the flash steam quotient increases to its maximum value 0.743.