【作者】 陈金增；

【导师】 黄素逸；

【作者基本信息】 华中科技大学 ， 工程热物理， 2010， 博士

【摘要】 船舶远海执行任务,人员、设备需消耗大量淡水,尤其对于蒸汽动力船舶,淡水消耗量更大,据统计,每人每天需饮用水5-10升,洗涤用水30升,蒸汽动力系统补充水约为蒸汽耗量的1-1.5%,如此大的淡水消耗单靠船舶携带的淡水远不能满足需要,而且储存于水柜中的淡水储存过程中会受细菌污染变质,不适于饮用要求,对于动力设备用淡水,水质要求高,高压动力锅炉给水含盐量要求低于5-10ppm,为满足船舶淡水需求,大中型船舶都装备有海水淡化装置；船舶海水淡化装置主要有蒸馏式和反渗透式两种,本文在详细分析目前海水淡化技术的基础上,对船舶上蒸汽作为热源的50T/d单效蒸馏、5T/d机械蒸汽压缩淡化装置及真空造水装置、45T/d多级闪发及5T/d反渗透式海水淡化装置进行了详细分析计算,分析各种淡化装置的特点及性能变化规律。针对目前的蒸汽加热式单效蒸馏装置进行改进,提出通过增加蒸汽喷射器形成热力蒸汽压缩海水淡化装置,并着重对船舶用热力蒸汽压缩式海水淡化装置进行了详细研究,计算表明,在目前50T/d单效蒸馏装置基础上,通过增加蒸汽喷射器形成热力蒸汽压缩海水淡化装置,节能效果可达50%以上,而且蒸汽喷射器本身可靠性高；在对装置进行模拟计算基础上,对其中的关键部件—蒸汽喷射器进行数值计算,利用气体动力学理论计算不同工作蒸汽压力、蒸发温度条件下喷射器性能变化规律,得出船舶热力蒸汽压缩海水淡化装置的蒸汽喷射器的设计参数及运行参数,为喷射器设计及淡化装置的使用操作提供理论依据。在对反渗透海水淡化装置进行分析的基础上,利用研制的反渗透海水淡化装置进行详细试验,分析不同工作压力、海水浓度、海水温度变化、PH值变化对产水量、产水浓度、耗功、回收率的影响,利用反渗透海水淡化分析软件ROSA5.4进行分析计算,获得反渗透海水淡化装置工作参数的变化规律,为反渗透海水淡化装置的设计与使用提供理论依据。同时,根据目前船舶反渗透海水淡化装置的实际,结合某船用150T/d反渗透海水淡化装置,设计了一台新型结构的压力转换器,并给出了结构参数计算方法,该压力转换器的突出特点在于采用弯曲流道,利用压力水在流道中流动形成的力矩驱动自身旋转,能量回收效率高,达到节能、降低产水成本的目的,计算表明,利用压力转换器进行反渗透海水淡化装置的能量回收,节能效果明显,节能可达60%以上,具有明显的经济效益。更多还原

【Abstract】 As an individul unit, the ship sails on the ocean for different tasks. Great quantity fresh water is needed for equipments and members, such as fresh water for boiler, desel motor, high pressure compressure, especially for ships propeled by steam turbine power plant, Most great displacement ships are equipted with seawater desalination plants for fresh water supply. The normal desalination technology used on ships is distallation or reverse osmosis. In this thesis, different kinds of marine desalination plants were analisized, such as 5T/d and 50T/d single-effect distillation plants,45T/d multi-stage flash distillation,2.5T/d and 5T/d reverse osmosis plants, the 5T/d mechinacal vapor compression desalination plant, and the distillation plant using heat pump as source of heat energy. The improvement methods to reserve energy for different kinds of marine desalination plants were gotten.For ships propeled by steam turbine power plants, the high quality fresh water consumption makes the distillation plant be used porpularly. In this thesis, based on analisizing the marine 50T/d distillation plant, an improving method by adding a steam-ejector to form marine vapor compressure desalination plant was presented. By thermo-dynamic calculation, a steam-ejector for vapor compressure desalination was designed. It was found that with an ejector to improve the single-effect distillation to form vapor compression distillation, the motive steam consumption was sharply discreased from 50T/d to 23T/d. For the distillation plant, a steam-ejector was designed and numerical sinmulinked. For different motive steam pressures and evaporate temperatures, the work characteristics of steam-ejector were gotten. It is usable for steam-ejector designing.With the development of reverse osmosis technology, more and more reverse osmosis plants were used on ships for fresh water supply. With the marine 5T/d RO plant, different work pressures, feed water concentritions and temperatures, and the PH of seawater were tested. With the ROSA5.0 software developed by DOM’s company, the basic datas of the plant were calculated. Comparing with the test datas, it was found that the calculation datas were accordingly to the test datas. The conclusions are usable for reverse osmosis plant operation.To reduce the power consumption of reverse osmosis deslination plant, by analysizing the different kinds of energy recovery equipments, a new structure pressure exchanger was designed for marine 150T/d reverse osmosis plant. And the calculation method was given. The main characteristic of this pressure exchanger is that the fluid ducts of the rotor unit are in curve. With the fluid flow through ducts, rotor can turn itself. Calculation and analisis shows that with this pressure exchange unit, the power consumption of this plant reduced more than 60%.更多还原