In order to concentrate the diluted sulfuric acid from the titanium dioxide(TiO2)production of sulphate process,a new concentration process was proposed by coupling chemical dehydration and multi-effect evaporation.Th...In order to concentrate the diluted sulfuric acid from the titanium dioxide(TiO2)production of sulphate process,a new concentration process was proposed by coupling chemical dehydration and multi-effect evaporation.The ferrous sulfate monohydrate(FeSO4·H2O),as the dehydrant,was added to the diluted sulfuric acid to form ferrous sulfate heptahydrate(FeSO4·7H2O)according to the H2SO4-FeSO4-H2O phase diagrams,which partially removes the water.This process was named as Chemical Dehydration Process.The residual water was further removed by two-effect evaporation and finally 70 wt%sulfuric acid was obtained.The FeSO4·H2O can be regenerated through drying and dehydration of FeSO4·7H2O.The results show that FeSO4·H2O is the most suitable dehydrant,the optimal reaction time of chemical dehydration process is 30 min,and low temperature is favorable for the dehydration reaction.45.17%of the entire removed water can be removed by chemical dehydration from the diluted sulfuric acid.This chemical dehydration process is also energy efficient with 24.76%saving compared with the direct evaporation process.Furthermore,51.21%of the FeSO4 dissolved originally in the diluted sulfuric acid are precipitated out during the chemical dehydration,which greatly reduces the solid precipitation and effectively alleviates the scaling in the subsequent multi-effect evaporation process.展开更多
In this paper, through two case studies, evaporation systems are considered in the context of overall process, and then are optimized to obtain energy-saving effect. The possible evaporation schemes are given when int...In this paper, through two case studies, evaporation systems are considered in the context of overall process, and then are optimized to obtain energy-saving effect. The possible evaporation schemes are given when integrated with the background process and how to optimize the evaporator is shown. From the case studies, it can be seen that sometimes incomplete integration and heat pump evaporation are better than complete integration so should be considered as candidate retrofit schemes.展开更多
Based on constructal theory,a rectangular parallel phase change microchannel model in a three-dimensional electronic device(TDED)is established with R134a as the cooling fluid.Based on the minimization of a complex fu...Based on constructal theory,a rectangular parallel phase change microchannel model in a three-dimensional electronic device(TDED)is established with R134a as the cooling fluid.Based on the minimization of a complex function(CF)composed of linear weighting sum of maximum temperature difference and pumping power consumption,constructal design of the TDED is conducted first;and then,maximum temperature difference and pumping power consumption are minimized by non-dominated sorting genetic algorithm-II methods.The results reveal that there exist an optimal mass flow rate(0.0012 kg/s)and a quadratic optimal aspect ratio(AR)(0.39)of the microchannel which lead to quadratic minimum CF(0.817).Compared with the original value,the CF after optimization is reduced by 18.34%.Reducing the inlet temperature of cooling fluid and microchannel number appropriately can help to enhance the overall performance of TDED.By using the artificial neural network and genetic algorithms in the toolboxes of Matlab software,the optimal AR gained in the Pareto solution set is located between 0.2–0.45.The smallest deviation index among three discussed strategies is 0.346,and the corresponding optimal AR is 0.413,which is selected as the optimal design strategy of the microchannel in the TDED under multiple requirements.The findings in this study can serve as theoretical guides for thermal designs of electronic devices.展开更多
Atmospheric moisture exploitation is emerging as a promising alternative to relieve the shortage of freshwater and energy.Efforts to exploit hygroscopic materials featuring flexibility,programmability,and accessibilit...Atmospheric moisture exploitation is emerging as a promising alternative to relieve the shortage of freshwater and energy.Efforts to exploit hygroscopic materials featuring flexibility,programmability,and accessibility are crucial to portable and adaptable devices.However,current two-dimensional(2D)or three-dimensional(3D)-based hygroscopic materials are dif-ficult to adapt to diverse irregular surfaces and meet breathability,which severely hinders their wide applications in wearable and programmable devices.Herein,hygroscopic organogel fibers(HOGFs)were designed via a wet-spinning strategy.The achieved fibers were composed of the hydrophilic polymeric network,hygroscopic solvent,and photothermal/antibacterial Ag nanoparticles(AgNPs),enabling hygroscopic capacity,photothermal conversion,and antibacterial.Owing to the good knittable feature,the HOGFs can be readily woven to adjusted 2D textiles to function as an efficient self-sustained solar evaporator of 4-layer woven HOGF device with a saturated moisture capacity of 1.63 kg m^(-2) and water-releasing rate of 1.46 kg m^(-2) h^(-1).Furthermore,the 2D textile can be applied as a wearable dehumidification device to efficiently remove the evaporative moisture from human skin to maintain a comfortable environment.It can reduce the humidity from 90 to 33.4%within 12.5 min.In addition,the introduction of AgNPs can also endow the HOGFs with antibacterial features,demonstrat-ing significant potential in personal healthcare.展开更多
Highly hydrophilic materials enable rapid water delivery and salt redissolution in solar-driven seawater desalination. However, the lack of independent floatability inhibits heat localization at the air/water interfac...Highly hydrophilic materials enable rapid water delivery and salt redissolution in solar-driven seawater desalination. However, the lack of independent floatability inhibits heat localization at the air/water interface. In nature, seaweeds with internal gas microvesicles can float near the sea surface to ensure photosynthesis. Here, we have developed a seaweed-inspired, independently floatable, but superhydrophilic (SIFS) solar evaporator. It needs no extra floatation support and can simultaneously achieve continuous water pumping and heat concentration. The evaporator resists salt accumulation, oil pollution, microbial corrosion, and protein adsorption. Densely packed hollow glass microbeads promote intrinsic floatability and heat insulation. Superhydrophilic zwitterionic sulfobetaine hydrogel provides a continuous water supply, redissolves the deposited salt, and endows the SIFS evaporator with excellent anti-fouling properties. With its unprecedented anti-contamination ability, this SIFS evaporator is expected to open a new avenue for designing floatable superhydrophilic materials and solving real-world issues of solar steam generation in complex environmental conditions.展开更多
基金the State Key Laboratory of Vanadium and Titanium Resources Comprehensive Utilization of China for its financial supportthe financial support of National Natural Science Foundation of China(Grant No.21576168)Science and Technology Cooperation Fund of Sichuan University-Panzhihua(No:2018CDPZH-23-SCU)。
文摘In order to concentrate the diluted sulfuric acid from the titanium dioxide(TiO2)production of sulphate process,a new concentration process was proposed by coupling chemical dehydration and multi-effect evaporation.The ferrous sulfate monohydrate(FeSO4·H2O),as the dehydrant,was added to the diluted sulfuric acid to form ferrous sulfate heptahydrate(FeSO4·7H2O)according to the H2SO4-FeSO4-H2O phase diagrams,which partially removes the water.This process was named as Chemical Dehydration Process.The residual water was further removed by two-effect evaporation and finally 70 wt%sulfuric acid was obtained.The FeSO4·H2O can be regenerated through drying and dehydration of FeSO4·7H2O.The results show that FeSO4·H2O is the most suitable dehydrant,the optimal reaction time of chemical dehydration process is 30 min,and low temperature is favorable for the dehydration reaction.45.17%of the entire removed water can be removed by chemical dehydration from the diluted sulfuric acid.This chemical dehydration process is also energy efficient with 24.76%saving compared with the direct evaporation process.Furthermore,51.21%of the FeSO4 dissolved originally in the diluted sulfuric acid are precipitated out during the chemical dehydration,which greatly reduces the solid precipitation and effectively alleviates the scaling in the subsequent multi-effect evaporation process.
文摘In this paper, through two case studies, evaporation systems are considered in the context of overall process, and then are optimized to obtain energy-saving effect. The possible evaporation schemes are given when integrated with the background process and how to optimize the evaporator is shown. From the case studies, it can be seen that sometimes incomplete integration and heat pump evaporation are better than complete integration so should be considered as candidate retrofit schemes.
基金supported by the National Natural Science Foundation of China(Grant No.52171317)Graduate Innovative Fund of Wuhan Institute of Technology(Grant No.CX2022073)。
文摘Based on constructal theory,a rectangular parallel phase change microchannel model in a three-dimensional electronic device(TDED)is established with R134a as the cooling fluid.Based on the minimization of a complex function(CF)composed of linear weighting sum of maximum temperature difference and pumping power consumption,constructal design of the TDED is conducted first;and then,maximum temperature difference and pumping power consumption are minimized by non-dominated sorting genetic algorithm-II methods.The results reveal that there exist an optimal mass flow rate(0.0012 kg/s)and a quadratic optimal aspect ratio(AR)(0.39)of the microchannel which lead to quadratic minimum CF(0.817).Compared with the original value,the CF after optimization is reduced by 18.34%.Reducing the inlet temperature of cooling fluid and microchannel number appropriately can help to enhance the overall performance of TDED.By using the artificial neural network and genetic algorithms in the toolboxes of Matlab software,the optimal AR gained in the Pareto solution set is located between 0.2–0.45.The smallest deviation index among three discussed strategies is 0.346,and the corresponding optimal AR is 0.413,which is selected as the optimal design strategy of the microchannel in the TDED under multiple requirements.The findings in this study can serve as theoretical guides for thermal designs of electronic devices.
基金supported by the Natural Science Foundation of China(52073295)Ningbo Science and Technology Bureau(2021Z127)+4 种基金Ningbo Public Welfare Science and Technology Plan Project(2021S150)The Sino-German Mobility Program(M-0424)Key Research Program of Frontier Sciences,Chinese Academy of Sciences(QYZDB-SSW-SLH036)Bureau of International Cooperation,Chinese Academy of Sciences(174433KYSB20170061)K.C.Wong Education Foundation(GJTD-2019-13).
文摘Atmospheric moisture exploitation is emerging as a promising alternative to relieve the shortage of freshwater and energy.Efforts to exploit hygroscopic materials featuring flexibility,programmability,and accessibility are crucial to portable and adaptable devices.However,current two-dimensional(2D)or three-dimensional(3D)-based hygroscopic materials are dif-ficult to adapt to diverse irregular surfaces and meet breathability,which severely hinders their wide applications in wearable and programmable devices.Herein,hygroscopic organogel fibers(HOGFs)were designed via a wet-spinning strategy.The achieved fibers were composed of the hydrophilic polymeric network,hygroscopic solvent,and photothermal/antibacterial Ag nanoparticles(AgNPs),enabling hygroscopic capacity,photothermal conversion,and antibacterial.Owing to the good knittable feature,the HOGFs can be readily woven to adjusted 2D textiles to function as an efficient self-sustained solar evaporator of 4-layer woven HOGF device with a saturated moisture capacity of 1.63 kg m^(-2) and water-releasing rate of 1.46 kg m^(-2) h^(-1).Furthermore,the 2D textile can be applied as a wearable dehumidification device to efficiently remove the evaporative moisture from human skin to maintain a comfortable environment.It can reduce the humidity from 90 to 33.4%within 12.5 min.In addition,the introduction of AgNPs can also endow the HOGFs with antibacterial features,demonstrat-ing significant potential in personal healthcare.
基金supported by the National Natural Science Foundation of China(21621004,21961132005,22078238,21908160,and 21805204)the Tianjin Natural Science Foundation(19JCQNJC05100 and 20JCQNJC00170)+1 种基金Young Elite Scientists Sponsorship Program by Tianjin(TJSQNTJ-2018-17)the China Postdoctoral Science Foundation(2019M651041).
文摘Highly hydrophilic materials enable rapid water delivery and salt redissolution in solar-driven seawater desalination. However, the lack of independent floatability inhibits heat localization at the air/water interface. In nature, seaweeds with internal gas microvesicles can float near the sea surface to ensure photosynthesis. Here, we have developed a seaweed-inspired, independently floatable, but superhydrophilic (SIFS) solar evaporator. It needs no extra floatation support and can simultaneously achieve continuous water pumping and heat concentration. The evaporator resists salt accumulation, oil pollution, microbial corrosion, and protein adsorption. Densely packed hollow glass microbeads promote intrinsic floatability and heat insulation. Superhydrophilic zwitterionic sulfobetaine hydrogel provides a continuous water supply, redissolves the deposited salt, and endows the SIFS evaporator with excellent anti-fouling properties. With its unprecedented anti-contamination ability, this SIFS evaporator is expected to open a new avenue for designing floatable superhydrophilic materials and solving real-world issues of solar steam generation in complex environmental conditions.
