基于低真空运行模式的水电联产系统热力分析  

Thermodynamic analysis of water-power cogeneration system based on low vacuum operation

作　　者：刘晓华[1] 杜宇[1] 沈胜强[1] 陈文博[1] 刘大伟[1] 

机构地区：[1]大连理工大学海洋能源利用与节能教育部重点实验室,辽宁大连116024

出　　处：《大连理工大学学报》2012年第1期11-15,共5页Journal of Dalian University of Technology

基　　金：中央高校基本科研业务费专项资金资助项目(DUT10ZD109);大连市建委科技计划资助项目(2010)

摘　　要：提出了对于低真空运行后的凝汽式机组,直接利用其末级排汽作为低温多效蒸馏海水淡化系统的加热汽源,从而实现水电联产的方法.采用矩阵法建立电厂热力系统多级回热数学模型,基于弗留格尔公式对低真空运行进行变工况计算,进而采用等温差法建立低温多效蒸馏海水淡化系统的数学模型.在计算范围内,当满足不同淡水产量的需求时,可以优选出最佳排汽温度和蒸发器效数,使得制水成本最低.此外,还讨论了各效温差值不同对水电联产系统经济性的影响.In order to achieve water-power cogeneration,the last-stage exhaust steam provided by condensing steam turbines under low vacuum operation is utilized as thermal resources for the low-temperature multi-effect distillation desalination system.Multi-stage heat-regenerative mathematical model of power plant thermodynamic system is constructed by matrix method.The off-design parameters under low vacuum operation are calculated on the basis of Friuli Nagel formula.Then,the mathematical model of low-temperature multi-effect distillation desalination system is built through equivalent temperature difference method.It can be concluded that within the selected temperature range of exhaust steam there exist optimal temperature of exhaust steam and the number of evaporators to make the fresh water cost lowest for different water demands.The effect of the temperature difference between desalination effects on the thermal economic performance of the water-power cogeneration system is also discussed.

关 键 词：海水淡化 低温多效蒸馏 凝汽式机组 低真空 水电联产 

分 类 号：TK114[动力工程及工程热物理—热能工程]