Experimental Study On Spray Flash Evaporation Of Seawater Desalination

It is well known that the shortage of fresh water has become one of the three biggest environmental problems in the 21st century. Therefore, the study on seawater desalination is taken more attention. Flash evaporation is the main one of the seawater desalination techniques, at present, so it is very useful to study flash evaporation.In this paper, the swirl nozzle was used in the flash chamber to do seawater desalination. And the temperature of the water and artificial seawater which were used to do flash evaporation is 24℃to 34℃.The factors such as superheat, inlet temperature which influence the flash evaporation are studied base on the experiment. The mechanism of the flash evaporation was also analysed.The non-equilibrium property of the flash evaporation was mainly studied. The phenomenon of the non-equilibrium temperature difference and its'influenced factors,such as superheat and inlet temperature, were analysed,and the general regularities were gained. The empirical correlation of non-equilibrium temperature difference is obtained based on the experimental data, and the error of it is not more than 20 percent.In addition, the factors of superheat and inlet temperature which influnce the flash evaporation temperature difference were analysed.Furtherly, the superheat and inlet temperature which influence on the flash evaporation ratio and the distillate production were studied,and a correlation between the flash evaporation temperature difference and the flash evaporation ratio was also obtained during this paper.According to the contrastive to the experimental data,the error of the correlation is not more than 20 percent.