低温多效海水淡化进料方式的比较与分析

COMPARISON AND ANALYSIS OF LT-MED FEED WATER ARRANGEMENTS

物料水进料方式决定着低温多效海水淡化装置的布置方式,对制水的经济性具有重要影响。对顺流进料、逆流进料和平流进料等几种进料方式的对比与分析表明,顺流进料方式蒸发器结垢风险最小,但经济性较差;逆流进料有效地改善了制水经济性,但需要多台中间进料泵,增加了系统的复杂性与运行电耗;平流进料盐水逐级自流,流程简单,经济性好。研究还表明,TVC的采用可显著降低蒸汽耗量和凝汽器的必要换热面积,有利于降低设备投资费用,提高制水经济性。

Feed arrangements determine the low temperature multi-effect desalination equipments layout,which remarkably affects the economical efficiency. It is showed by comparison and analysis of forward,backward and parallel arrangement of feed water to the evaporators of MED that forward feed arrangement is less efficient although with least trouble of scaling,the backward feed arrangement is more efficient than the forward one whereas the use of relay pumps increases the complexity and power consumption of the process,while the brine of parallel feed arrangement flows spontaneously from one effect to the next,which simplifies the technological process with economical efficient. It is also showed that the application of TVC significantly decreases the motive vapor consumption and essential heat transfer area of condenser,which reduces the equipment cost and efficiently improves the gained output ratio （GOR） of MED.