六效平流MED-TVC海水淡化系统[火用]分析

Exergy analysis of six effect parallel feed MED-TVC system

在热法海水淡化工业中,多效蒸馏-热蒸汽压缩(MED-TVC)系统因其较低的蒸汽消耗量而受到广泛的应用。本文针对电厂六效平流MED-TVC海水淡化系统进行了热力学和[火用]分析。揭示了系统[火用]损失变化,为进一步优化系统能量结构提供了方向。并进一步研究了动力蒸汽压力、进料海水盐度以及抽吸位置对系统性能的影响。结果表明动力蒸汽压力的增加有利于提高系统造水比但同时也增加了系统的能量及[火用]输入。抽吸位置在第四效时系统的输入[火用]及[火用]损耗较小,单位面积产水量最高。

In the thermal desalination industry,the MED-TVC system was widely used because of its low steam consumption.In this paper,a comprehensive thermodynamic and exergy analysis of six effect advection MED-TVC system in power plant was carried out.The change of exergy loss of the system was revealed,which provided a direction for further optimization of the energy structure of the system.Furthermore,the effects of steam pressure,salinity of feed water and suction position on the performance of the system were studied.The results show that the increase of steam pressure is beneficial to the increase of water production ratio,but also increases the energy and exergy input of the system.When the suction position is in the fourth effect,the input exergy and exergy loss of the system are small,and the water yield per unit area is the highest.