基于太阳能与尾气废热利用的渔船用海水淡化装置设计

Design of desalination unit for fishing vessels with combination of solar energy and waste heat

为满足中小型渔船船员饮用水问题，设计了一种利用柴油机尾气废热与太阳能相结合的海水淡化装置。该装置由柴油机、太阳能空气集热器、壳管式海水蒸发器及板式冷凝器组成，利用柴油机废热与太阳能作为热源，废气经蒸发器与海水进行热质交换；同时，太阳能集热器的热空气经曝气管与海水鼓泡增湿，产生的水蒸气由冷凝器凝结为淡水。柴油机废气的排放量、温度和温差对造水量有很大影响，废气的出口温度在150～250℃时，随着温度的增加，造水量逐渐增多，废气的排放温度保持在208℃，海水淡化装置的造水率保持在20kg／h，能够满足中小型渔船8—10名船员的生活需求。

In order to solve the crews＇ drinking improve the quality of drinking water, a sea water problems of the small-and medium-size fishing vessels and water desalination unit which works through the combination of diesel engine exhaust heat and solar energy. The unit consists of diesel, solar air collector, shell-and-tube seawater evaporator, plate-type heat exchanger. The primary heat source of this unit is diesel engine waste heat and solar energy. Heat and mass exchange operates between the exhaust gas and seawater though the evaporator, meanwhile the hot air of auxiliary solar collector bubbles and humidifies with seawater though the aeration tube, and then the water vapor produced by the plate heat exchanger condenses into freshwater. Diesel exhaust emissions, temperature and the temperature difference have a great influence on water production capacity. When the temperature of the exhaust gas outlet maintain 150-250 ℃, water production capacity increases gradually along with the increase of the temperature. If the exhaust gas temperature at 208 ℃ is maintained, desalination unit will make water-producing rate continued at 20kg/h, it is able to meet 8 to 10 crews＇ living needs of the small-and medium-size fishing vessel.