低温多效蒸馏海水淡化设备大型化的技术研究

在2.5万t/d低温多效蒸馏(LT-MED)海水淡化试验装置上通过改变工艺参数,考察装置操作温度、工艺流程、蒸发器换热管布置、物料海水流量及其过冷度对淡水产量的影响。结果表明,在工作蒸汽量相同的条件下,低温2效产水量只有高温2效产水量的50%～70%;适当预热物料海水,有利于提高蒸发器的工作效率;换热管倾斜布置,对提高蒸发器换热效果作用不显著;加大物料海水喷淋量将减小淡水产量和造水比,喷淋密度宜保持在0.04～0.06kg/ms范围内。

STUDY ON SIZE - ENLARGING TECHNOLOGY OF SEA - WATER DESALINATION EQUIPMENT BY USING LOW- TEMPERATURE MULTI - EFFECT DISTILLATION

On interim-test equipment of sea-water desalination using low-temperature and multi-effect distillation(LT-MED) with output capacity of 25-thousand t/d,through changing the technological parameters,the influence of working temperature in operation of equipment,technological process,arrangement of heat-exchaning pipes in the evaporater,flow rate of material and sea-water,and degree of over cooling upon the output of fresh water has been investigated.Results show that the water yield under condition of low temperature and two-effect mode is only 50%~70% of that in high-temperature and two-effect mode;suitably preheating material and sea-water is advantageous to enhance the work efficiency of the evaporator;the declination arrangement of heat-exchanging pipes hasn’t substantial effectiveness for enhancing the heat-exchanging in evaporator;increasing the spray amount of material and sea-water will decrease the output of fresh water and the water-making ratio;and the spraying density is adequate to maintain in a range of 0.04~0.06 kg/ms.