1. Department of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China; Center for Environmental Energy Engineering (CEEE), Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA 2. 西安交通大学能源与动力工程系，中国西安 710049 3. 马里兰大学帕克分校机械工程系环境能源工程中心（CEEE），美国马里兰州 20742
Modeling analysis on solar steam generator employed in multi-effect distillation (MED) system
Zhaorui ZHAO1(), Bao YANG3, Ziwen XING2
1. Department of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China; Center for Environmental Energy Engineering (CEEE), Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA 2. Department of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an 710049, China 3. Center for Environmental Energy Engineering (CEEE), Department of Mechanical Engineering, University of Maryland, College Park, MD 20742, USA
Recently the porous bilayer wood solar collectors have drawn increasing attention because of their potential application in solar desalination. In this paper, a thermodynamic model has been developed to analyze the performance of the wood solar collector. A modeling analysis has also been conducted to assess the performance and operating conditions of the multiple effect desalination (MED) system integrated with the porous wood solar collector. Specifically, the effects of operating parameters, such as the motive steam temperature, seawater flow rate, input solar energy and number of effects on the energy consumption for each ton of distilled water produced have been investigated in the MED desalination system combined with the bilayer wood solar steam generator. It is found that, under a given operating condition, there exists an optimum steam generation temperature of around 145°C in the wood solar collector, so that the specific power consumption in the MED system reaches a minimum value of 24.88 kWh/t. The average temperature difference is significantly affected by the solar heating capacity. With the solar capacity increasing from 50 kW to 230 kW, the average temperature difference increases from 1.88°C to 6.27°C. This parametric simulation study will help the design of efficient bilayer wood solar steam generator as well as the MED desalination system.
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