Research On New Technology Of Water Harvest From Air And Seawater Desalination Based On Solar Chimney

Global warming may change the air circulation pattern and increase the frequency of outbreaks of extreme weather events such as drought,heat waves,heavy rains and floods around the world.In recent years,the El Nino phenomenon has made drought become more and more serious,and the demand for sustainable freshwater is increasing.With the rapid development of solar chimney technology,it is reported that the solar chimney system in the output of electricity at the same time there is the possibility of water harvest from air and desalination applications,this article will focus on the new technology of water harvest from air and desalination based on solar chimney.Firstly,based on the analysis of the development of solar chimney technology researches,the mechanism of the technology of water harvest from air based on solar chimney is theoretically analyzed,and the environmental and economic benefits brought by water harvest from air technology are discussed.Secondly,a new type of solar chimney system with collector being replaced by black tubes around the chimney to warm water and air is proposed,combined with water production and power generation.One-dimensional compressible flow and heat transfer mathematical model has been developed to describe the moist air which cools down along the chimney and condenses above the lifting condensation level.The feasibility and effectiveness of the new solar chimney system for water production are verified by comparing the calculated water output with the natural rainfall of the city stations.By analyzing the sensitivity of the key parameters affecting the water production and power generation performance of the system,it is concluded that the height of the chimney has a great influence on the amount of condensed water,and the relationship between the condensed water and the output power of the system is mutually restricted.The optimal design method of total power and total efficiency is put forward.At last,the desalination performance of Manzanares pilot model was numerically investigated by establishing the three-dimensional compressible flow and heat transfer mathematical model to describe the moist air which cools down along the chimney and condenses above the lifting condensation level.The optimization method of desalination performance of sprayed humidification at the entrance of chimney is proposed.The results show that with the increase of the amount of spray droplets,the higher the mass fraction of water in the air,the greater the influence of the microclimate in the local environment.The evaporation of the spray droplets improves the relative humidity of the air inside the chimney,and the condensation level thus can be greatly reduced.Moreover,the output of freshwater is increasing with the increase of the amount of spray droplets,which is beneficial to improve the desalination efficiency of the system.In this article,the new technology of water harvest from air and seawater desalination based on solar chimney is analyzed and optimized from theoretical analysis,theoretical calculation and numerical simulation,which is a more comprehensive study of theory,technology,feasibility and economy,etc.For the future development of solar chimney technology applications,this article will be a good reference.