太阳能利用的多级闪蒸海水淡化装置热力过程计算
时间:2020-10-23 20:23 来源:毕业论文 作者:毕业论文 点击:次
摘 要 随着经济社会的高速发展,人类对淡水资源的需求越来越大。水资源的短缺问题日益突出,这已经制约了一些国家经济的发展和人民生活水平的提高。因海水资源丰富且分布广泛,发展海水淡化产业是解决这一问题的有力措施。传统海水淡化方式虽技术成熟,但能源消耗量大,生产成本较高,在推广上面临一些问题,尤其在能源短缺的地方。多级闪蒸海水淡化装置运行稳定可靠,产水品质好,但能源消耗量大,为此将太阳能热利用技术用于多级闪蒸海水淡化中,一方面可以降低能耗,节约生产成本;另一方面可以减少化石燃料燃烧带来的污染,具有现实意义。 本文对太阳能多级闪蒸海水淡化装置进行了理论分析,根据能量守恒和质量守恒,运用热力学热一律和传热学换热理论方法对装置的工艺参数进行了设计计算,确定了装置的海水流量、各级操作温度和压力、各级淡水产量、冷凝管传热面积以及进料海水在各级冷凝管的出口温度,从而得出了装置的热量需求。本文也根据太阳能的辐射强度和装置的热量需求,对太阳能集热器进行了选型计算,确定了集热器的型号与数量。通过对太阳能多级闪蒸海水淡化装置热力参数的设计计算,为装置的结构设计提供了依据,也为装置今后的优化设计提供了参考。同时,本文设计的小型太阳能多级闪蒸海水淡化装置,可以用来缓解沿海地区或岛屿居民的淡水短缺问题。 58548 毕业论文关键词:多级闪蒸; 海水淡化; 太阳能; 传热 Abstract With the rapid development of economic society, the human demand for fresh water is greater and greater, and the water shortage problem becomes increasingly serious, which has been restricting the development of some national economy and the improvement of people's living standards. Because the seawater resources are rich and widely distributed, developing seawater desalination industry is an effective measure to solve the problem. Traditional technologies of desalination are mature, but energy consumption is large, and the production cost is high, so there are some problems in the promotion, especially in those energy shortage area. Multi-stage flash desalination device operation is stable and reliable, and water product is in good quality, but energy consumption is large, so solar heat utilization technology is applied to mul ti-stage flash desalination, which is practical significant. On the one hand, it can reduce the energy consumption and save production cost; On the other hand i t can reduce the pollution caused by the burning of fossil fuels. In this paper, theory analysis for based on solar energy using mul ti-stage flash desalination device has been carried out. According to the conservation of energy and mass, some basic process parameters have been worked out with the first law of thermodynamics and heat transfer theory, such as device running seawater flow, operating temperature and pressure of each stage, fresh water production, condensing tube heat transfer acreage and feed water in the outlet temperature of condenser pipe at each stage. Thus device heat demand is got. In this article,according to the intensity of solar radiation and the device heat demand, the type of solar collector is selected and determine quantity of the collector. Based on the thermodynamics parameters calculation of solar energy multi-stage flash desalination device, this paper provides reference for structural design or optimal design of the device in future. And the device could relieve the problem of fresh water shortage in coastal areas. Keyword: multi-stage flash ; seawater desalination ; solar energy ; heat transfer. 目录 (责任编辑:qin) |