Performance of parallel feed multiple effect evaporation system for seawater desalination

Performance analysis is presented for the parallel feed multiple effect evaporation system. Two operating modes are considered in the analysis, which includes the parallel and the parallel/cross flow systems. Analysis is performed as a function of the heating steam temperature, salinity of the intake seawater, and number of effects. Results are presented as a function of parameters controlling the unit product cost, which includes the specific heat transfer area, the thermal performance ratio, the conversion ratio, and the specific flow rate of the cooling water. Results indicate that better performance is obtained for the parallel/cross flow system. However, the parallel feed system has similar characteristics and simpler design and operation procedures. Performance of both systems is consistent with literature data. Comparison of the two parallel feed systems versus conventional multistage flash desalination and the forward feed multiple effect evaporation schemes show that the forward feed system has better performance characteristics than the other three systems.