Study On Air-Gap Diffusion Distillation Seawater Desalination

Water is the source of life,It is also the necessary for the development of the human society.However,the fresh water resources on the earth are scarce and distribute uneven.The sharply development of industry need more fresh water,the shortage of fresh water resources has become a serious problem for mankind.The amount of fresh water in China ranks fourth in the world,however,the amount of fresh water owned by per capita in china is only one-fourth of the world's.In order to solve the problem of water shortage,the most effective method is to produce fresh water,that is,seawater desalination,about 97.5% of the total water storage on the earth is seawater,which can provide sufficient supply liquid for desalination technology.Desalination technology has receiving more and more attention from many countries.The air-gap diffusion distillation seawater desalination(AGDD)proposed in this paper has the advantages of operation in normal pressure,equipment simple,and low-grade heat source recovery.It can be used in water treatment.In this paper,the study of air-gap diffusion seawater desalination technology is based on the combination of experiment and calculation.The air-gap diffusion seawater desalination model is built and analyzed,and the heat and mass transfer analysis is carried out according to the law of mass conservation and the law of energy conservation.The air-gap diffusion seawater desalination was simulated in MATLAB.The experimental platform of the AGDD device was built,we changed the operating parameters of the experimental device and the size of the device to analyzed the operating conditions of the device.The experimental contents include: changing the inlet temperature of the cold flow to 20 ?,25 ?,and 30 ?,respectively,changing the inlet temperatures of the heat flow to 50 ?,55 ?,60 ?,and65 ?,respectively,changing the flow rate of the working fluid to 2 kg/ h,3kg/h,4kg/h,and5kg/h,respectively,changing the air gap width of the experimental device to 5mm,8mm,10 mm,respectively,and the height of the device to 0.9m and 1.8.Compared the experimental results with the simulated calculation results,to analyze the influence of the operating parameters and dimensions of the device on the seawater desalination performance of the device,which will provides guidance for further research on air gap diffusion distillation seawater desalination.