利用LNG冷能水合物海水淡化-冷电联产系统

A Combined System of Hydrate Seawater Desalination,Cooling and Power Generation Using LNG Cold Energy

液化天然气冷能的再汽化温度区间跨度大,传统单一的冷能利用方式很难实现高效利用。而现阶段的多联产系统大多以串联方式进行耦合,会存在不同利用方式温度区间重叠的问题,无法使各个单元均处在最佳的温度区间。针对这一问题,本文提出了一种混联耦合的水合物海水淡化-冷电联产系统,对系统中5种参数进行了敏感性分析。最后分别以系统的效率和净现值为目标函数进行优化,其最高效率可达42.93%,最高净现值为593×10^(6)USD。并分析两种优化方案下的传热匹配和冷量分配情况,为提高未来LNG冷能利用的多联产系统能量效率和经济性,打下了良好的基础。

The regasification temperature range of cold energy of liquefied natural gas is large,and the traditional single cold energy utilization method is difficult to achieve efficient utilization.However,most of the current polygeneration systems are coupled in series mode,and there will be the problem of overlapping temperature intervals of different utilization modes,so that each unit cannot be in the best temperature interval.In order to solve this problem,this paper proposes a hybrid coupled system of hydrate desalination,cooling and power generation,and carries out sensitivity analysis on five system parameters.Finally,the exergy efficiency and net present value of the system are respectively used as objective functions to be optimized.The maximum exergy efficiency is 42.93%and the maximum net present value is 5.93×10^(8) USD.The heat transfer matching and cold energy allocation under the two optimization schemes are analyzed.It lays a good foundation for improving the energy eficiency and economy of polygeneration system for LNG cold energy utilization in the future.