Solar evaporation attracted lots of attention due to its environment-friendly and high efficiency,which is a potential approach to collecting fresh water.Many efforts have been made to improve the evaporation rate in ...Solar evaporation attracted lots of attention due to its environment-friendly and high efficiency,which is a potential approach to collecting fresh water.Many efforts have been made to improve the evaporation rate in the open space.While the actual water collection rate is far less than the evaporation rate,especially in passive water collection,limiting its practical and scalable applications.In this review,we focus on freshwater collection based on solar evaporation.Firstly,heat and mass transfer behaviors on the evaporation side were summarized to improve evaporation performance,including heat transfer processes in thermal radiation,convection,and conduction;mass transfer processes in water supply,evaporation enthalpy,and salt rejection.Sequentially,subcooling,wettability,and geometry of the condensation side were discussed to improve water collection performance,which should be designed collaboratively with the evaporation side in a confined space.Finally,thermal recovery and electricity generation beyond water collection were also introduced,and some challenges still need to improve in the further for scalable and practical applications,including passive water collection rate,integrated system,and long-term issues.展开更多
This paper is based on the rainwater collection project in the retrofit of the Dongyi teaching block in Zhejiang University Xixi Campus.The analysis incorporates the local meteorological data, recycling water utilizat...This paper is based on the rainwater collection project in the retrofit of the Dongyi teaching block in Zhejiang University Xixi Campus.The analysis incorporates the local meteorological data, recycling water utilization, and precipitation adjustment.The rainwater collection system in this program also adds the condensation water from the heating, ventilation and air conditioning （ HVAC） system and the concentration from the reverse-osmosis system used for watering greens and supplying waterscapes.By calculating, the quantity of the HVAC condensation water in summer is 3.48 m3/d, and the quantity of the reverse-osmosis concentrated water is 198 to 396 L/d.This method solves the water shortage caused by high evaporation in summer and low precipitation in winter.Supported by empirical monitoring data, the proposed method significantly increases the economic efficiency of the system during the summer period.展开更多
基金financially supported by the Central South University Innovation-Driven Research Programme(2023CXQD012).
文摘Solar evaporation attracted lots of attention due to its environment-friendly and high efficiency,which is a potential approach to collecting fresh water.Many efforts have been made to improve the evaporation rate in the open space.While the actual water collection rate is far less than the evaporation rate,especially in passive water collection,limiting its practical and scalable applications.In this review,we focus on freshwater collection based on solar evaporation.Firstly,heat and mass transfer behaviors on the evaporation side were summarized to improve evaporation performance,including heat transfer processes in thermal radiation,convection,and conduction;mass transfer processes in water supply,evaporation enthalpy,and salt rejection.Sequentially,subcooling,wettability,and geometry of the condensation side were discussed to improve water collection performance,which should be designed collaboratively with the evaporation side in a confined space.Finally,thermal recovery and electricity generation beyond water collection were also introduced,and some challenges still need to improve in the further for scalable and practical applications,including passive water collection rate,integrated system,and long-term issues.
文摘This paper is based on the rainwater collection project in the retrofit of the Dongyi teaching block in Zhejiang University Xixi Campus.The analysis incorporates the local meteorological data, recycling water utilization, and precipitation adjustment.The rainwater collection system in this program also adds the condensation water from the heating, ventilation and air conditioning （ HVAC） system and the concentration from the reverse-osmosis system used for watering greens and supplying waterscapes.By calculating, the quantity of the HVAC condensation water in summer is 3.48 m3/d, and the quantity of the reverse-osmosis concentrated water is 198 to 396 L/d.This method solves the water shortage caused by high evaporation in summer and low precipitation in winter.Supported by empirical monitoring data, the proposed method significantly increases the economic efficiency of the system during the summer period.
