利用LNG冷能的间接冷冻法海水淡化流程及其初步分析

Preliminary analysis of the process of indirect freezing desalination of sea water utilizing LNG cold energy

介绍了一种利用LNG冷能进行海水淡化的间接冷冻法,即利用二次冷媒传递LNG气化过程中放出的冷量于海水的结冰过程,最终得到淡水。叙述其流程和优点,并指出选择二次冷媒的原因。对实验样机中的关键部件——结晶器的换热面积进行了估算,并给出其结冰过程中换热量、冰层厚度、换热系数等相关参数随时间的变化趋势。最后从能量效率和火用效率角度考察LNG冷能的利用效率。

An indirect freezing desalination method utilizing LNG cold energy was presented. In this process, the secondary refrigerant transfered the cold energy of the LNG gasification to the sea water freezing. The reason of choosing the secondary refrigerant was darified, and the advantages of the process were also pointed out. The heat transfer area of the crystallizer, the key dement of the whole process, were estimated for an experimental apparatus, and the curves of heat, ice thickness and heat transfer coefficient during the ice - forming process were also given. Finally, the energy efficiency and the exergy efficiency of utilizing LNG cold energy were evaluated respectively.