考虑不同水质输入的水电联产优化设计

Optimal Design of Desalination and Power Cogeneration System Considering Different Salinity Feed Water

结合已有的反渗透/多级闪蒸混产系统和发电多级闪蒸联产系统,设计了一个新的包括热力发电系统、反渗透海水淡化系统和多级闪蒸海水淡化系统的水电联产超结构,对以不同盐度苦咸水、海水为原水的水电联产系统进行了优化设计,通过求解系统以年费用最小为目标函数的非线性数学模型,得到不同盐度下联产系统优化的生产结构.结果表明,在低盐度（≤25000mg/L）下采用冷凝式发电和一级反渗透产水,高盐度下采用抽汽冷凝式发电和热膜混合产水,可降低联产系统的年费用,获得较低成本的淡化水.在本工作所定的生产规模下,优化联产方案的年费用可降低23%~36%.

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 （~〈25 000 mg/L）, the optimal cogeneration structure is condensing power generation and one stage RO desalination; when the salinity〉25 000 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.