Optimal Design of Desalination and Power Cogeneration System Considering Different Salinity Feed Water
WU Xian-li HU Yang-dong WU Lian-ying
College of Chemistry and Chemical Engineering, Ocean University of China Chemistry and Chemical Engineering Institute of Ocean University of China Qingda Chemistry and Chemical Engineering Institute of Ocean University of China Qingda
Abstract：Combined with the RO/MSF hybrid system and MSF-power cogeneration system, a new cogeneration system, including the coal-fired thermal power plant, MSF system and RO desalination system, is designed. A simplified superstructure model of the system is presented, which includes all the possible alternative configurations of the cogeneration system. Its production structure, using different salinity brackish water and seawater as feed water, is optimized. By solving the non-linear programming mathematical model of the cogeneration system with the objective of minimizing annual cost, an optimal cogeneration system can be obtained. The results show that at the low salinity (≤25000 mg/L), the optimal cogeneration structure is condensing power generation and one stage RO desalination; when the salinity>25000 mg/L, extraction condensing power generation and RO/MSF hybrid system is the optimal cogeneration system. The optimal cogeneration solution can reduce 23%~36% of the total annual cost.