聚光管式太阳能苦咸水淡化系统性能研究

发布时间：2018-05-02 10:58

  本文选题：管式 + 苦咸水淡化　； 参考：《内蒙古工业大学》2017年硕士论文

【摘要】：随着世界淡水资源的匮乏和化石能源的日益枯竭,利用太阳能聚光集热技术产生热能驱动苦咸水淡化装置生成淡水将是缓减淡水短缺的有效途径之一。尤其在人口密度低,降雨量少、阳光充足的地区进行太阳能苦咸水淡化的意义显而易见。常规使用的多级闪蒸或低温多效苦咸水淡化装置需要一定的规模要求,为此,提出一种可以小规模生产、分布式应用的聚光管式太阳能苦咸水淡化系统,该系统结构简单,维护方便,能够满足偏远地区的淡水需求。本文介绍了新型聚光管式太阳能苦咸水淡化系统的结构和工作原理,设计了为管式太阳能苦咸水淡化装置的供能槽式复合多曲面聚光集热器,给出了组成聚光集热器的抛物线方程,利用光学仿真软件对影响聚光器性能的接收体形状、入射偏角、安装误差等参数进行了计算和仿真研究,得到该聚光器的跟踪精度要求。同时,搭建槽式复合多曲面聚光器性能测试试验台,并对带冷却装置的板式太阳能电池接收体的光热性能进行测试。结果表明,在近2倍聚光比条件下,换热工质为水,进水流量为2.41 g/s时,该系统的综合性能效率可达69.88%。分析了管式太阳能苦咸水淡化装置内部传热传质过程,给出了理论产水量的计算方法。搭建管式太阳能苦咸水淡化产水性能测试试验台,对影响该装置产水性能的苦咸水水膜厚度、进水流量等分别进行了试验研究,同时对该装置进行了定功率加热过程产水量和温度测试。研究表明,在定功率加热试验中,该装置最大的性能系数为0.80。为了提高聚光管式太阳能苦咸水淡化装置的淡水产量,本文探索了强化装置内部传热传质的方法和途径,分别对回热运行工况、负压运行工况、风冷负压运行工况和水冷负压运行工况时的装置淡水产量和蒸发、冷凝温度变化进行了分析研究。结果表明,当运行温度为50℃,运行压力从100kPa减小到75kPa时,淡水产量增加了43%。在水冷负压运行工况下中,当运行温度为70℃,运行压力为75kPa时,装置稳定运行淡产水量为683.8g/h,比同工况下无水冷的产水量提高289%。通过提高蒸发冷凝温差、减少装置内部的不凝气体均可以实现强化装置内部传热传质过程的目的,进而有效地提高装置的淡水产量。
[Abstract]:With the shortage of fresh water resources and the depletion of fossil energy in the world, it is one of the effective ways to reduce the shortage of fresh water by using solar energy gathering technology to generate heat energy to drive brackish water desalination device to generate fresh water. Especially in areas with low population density, low rainfall and abundant sunshine, the significance of desalination of brackish water by solar energy is obvious. The conventional multi-stage flash or low-temperature multi-effect brackish water desalination device needs certain scale requirement. Therefore, a kind of concentrated light tube solar brackish water desalination system with small scale production and distributed application is put forward, which has a simple structure. Convenient maintenance to meet the freshwater needs of remote areas. This paper introduces the structure and working principle of a new type of solar brackish water desalination system with condensing tube, and designs the energy supply trough type multi-curved condensing collector for the tubular solar brackish water desalination device. The parabola equation of the concentrator is given. The parameters such as the shape of the receiver, the angle of incident deflection and the installation error which affect the performance of the concentrator are calculated and simulated by using the optical simulation software, and the tracking accuracy requirements of the concentrator are obtained. At the same time, the performance test bench of the slot composite multi-curved concentrator is built, and the photothermal performance of the plate solar cell receiver with cooling device is tested. The results show that when the heat transfer medium is water and the influent flow is 2.41 g / s, the comprehensive performance efficiency of the system can reach 69.88 under the condition of close to 2 times concentrated light ratio. The heat and mass transfer process in the tube solar desalination unit is analyzed, and the calculation method of theoretical water production is given. A tubular test rig was set up to test the water production performance of solar brackish water desalination. The thickness of brackish water film and the influent flow rate, which affect the water production performance of the device, were tested and studied respectively. At the same time, the water production and temperature of the device were measured during the constant power heating process. The results show that the maximum performance coefficient of the device is 0.80 in constant power heating test. In order to increase the fresh water output of the solar brackish water desalination device, the methods and ways of enhancing heat and mass transfer inside the unit are explored in this paper. The fresh water output, evaporation and condensing temperature of the unit under the operating conditions of air-cooled negative pressure and water-cooled negative pressure are analyzed and studied. The results showed that when the operating temperature was 50 鈩，

本文编号：1833591