The Experts below are selected from a list of 183 Experts worldwide ranked by ideXlab platform
Xuelai Zhang - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation on Inorganic Salt Solution s undercooling degree under the action of porous media and different concentrations
Journal of Thermal Analysis and Calorimetry, 2019Co-Authors: Xuelai ZhangAbstract:The undercooling degree of Inorganic Salt Solution has great effect on the characteristic of phase change materials in cooling storage methods. Ammonium chloride Solution was chosen as a kind of Inorganic Salt Solution, and the experimental system was built to study the influence on supercooling degree of Inorganic Salt Solution under the effection of concentration and porous media. The heat transfer enhancement method was studied by changing the concentration of Inorganic Salt Solution and the diameter of pellets constituting the porous media. The experimental results show that with the increase in concentration, the value of Inorganic Salt Solution’s supercooling degree and dispersion degree reduced, while the stability increased. The undercooling degree of the 15% ammonium chloride Solution decreased by 17.5% compared to the 5% ammonium chloride Solution. As the pellet diameter constituting the porous media decreased, the average value of the Solution’s undercooling degree and dispersion degree also decreased, while the stability increased. The average value of the Solution’s undercooling degree decreased by 21.7% when using 5-mm-diameter pellets compared to the ammonium chloride Solution without porous media.
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Experimental investigation on Inorganic Salt Solution’s undercooling degree under the action of porous media and different concentrations
Journal of Thermal Analysis and Calorimetry, 2018Co-Authors: Xuelai ZhangAbstract:The undercooling degree of Inorganic Salt Solution has great effect on the characteristic of phase change materials in cooling storage methods. Ammonium chloride Solution was chosen as a kind of Inorganic Salt Solution, and the experimental system was built to study the influence on supercooling degree of Inorganic Salt Solution under the effection of concentration and porous media. The heat transfer enhancement method was studied by changing the concentration of Inorganic Salt Solution and the diameter of pellets constituting the porous media. The experimental results show that with the increase in concentration, the value of Inorganic Salt Solution’s supercooling degree and dispersion degree reduced, while the stability increased. The undercooling degree of the 15% ammonium chloride Solution decreased by 17.5% compared to the 5% ammonium chloride Solution. As the pellet diameter constituting the porous media decreased, the average value of the Solution’s undercooling degree and dispersion degree also decreased, while the stability increased. The average value of the Solution’s undercooling degree decreased by 21.7% when using 5-mm-diameter pellets compared to the ammonium chloride Solution without porous media.
Lin Liang - One of the best experts on this subject based on the ideXlab platform.
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energy saving analysis for a Solution evaporation system with high boiling point elevation based on self heat recuperation theory
Desalination, 2015Co-Authors: W F He, Lin Liang, Wenhao PuAbstract:Abstract This paper focuses on the application of self-heat recuperation theory (SHRT) in mechanical vapor recompression (MVR) evaporation systems when used to concentrate Solutions with boiling point elevation (BPE). A nonlinear model is presented and used to analyze the advantages of heat recovery and multi-stage MVR over single-stage MVR. The model is then used to optimize the number of stages, evaporation temperatures, heat transfer temperature differences and stage concentration changes in relation to the compressor energy requirements. In comparison with single-stage MVR and conventional three-effect evaporation, multi-stage MVR with SHRT is shown to offer advantages when the number of stages is large, the evaporation temperatures are high and a large mass concentration difference between the outlet and inlet is required. However, the SHRT-based MVR system does not always yield energy savings when dealing with an Inorganic Salt Solution with high BPE. A case study on concentrating a calcium chloride Solution indicates that the SHRT-based MVR system uses more energy when the inlet mass fraction is over 38% compared to the conventional three-effect evaporation technology.
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Energy saving analysis for a Solution evaporation system with high boiling point elevation based on self-heat recuperation theory
Desalination, 2015Co-Authors: Han Dong, Lin Liang, Chen Yue, He Weifeng, Pu WenhaoAbstract:This paper focuses on the application of self-heat recuperation theory (SHRT) in mechanical vapor recompression (MVR) evaporation systems when used to concentrate Solutions with boiling point elevation (BPE). A nonlinear model is presented and used to analyze the advantages of heat recovery and multi-stage MVR over single-stage MVR. The model is then used to optimize the number of stages, evaporation temperatures, heat transfer temperature differences and stage concentration changes in relation to the compressor energy requirements. In comparison with single-stage MVR and conventional three-effect evaporation, multi-stage MVR with SHRT is shown to offer advantages when the number of stages is large, the evaporation temperatures are high and a large mass concentration difference between the outlet and inlet is required. However, the SHRT-based MVR system does not always yield energy savings when dealing with an Inorganic Salt Solution with high BPE. A case study on concentrating a calcium chloride Solution indicates that the SHRT-based MVR system uses more energy when the inlet mass fraction is over 38% compared to the conventional three-effect evaporation technology. (C) 2014 Elsevier B.V. All rights reserved
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Analysis of energy saving for ammonium sulfate Solution processing with self-heat recuperation principle
Applied Thermal Engineering, 2014Co-Authors: W F He, Wenhao Pu, Lin LiangAbstract:Abstract As an important production process, the evaporative concentration of the Inorganic Salt Solution is extensively applied in the industry, and it is significant to investigate the energy saving potential of such evaporation systems. In the paper, taking the ammonium sulfate Solution for example, the self-heat recuperation technology (SHRT) is utilized to design two mechanical vapor recompression (MVR) systems, and the relevant energy saving performance is analyzed. It is found that the designed systems, which are satisfied with SHTR, enable the recovery of the sensible and latent heat of the emission Solution without any additional heat, and compared to the conventional three-effect evaporation system, the energy saving performance are more prominent. However, in view of the existence of the boiling point elevation (BPE) for the Inorganic Salt Solution, a maximum reduction amplitude of 40% of the energy saving performance for the double-stage MVR system is obtained compared with the single-stage MVR system. As a result, it is concluded that the only satisfaction to the SHRT is not enough, and the pattern of the MVR system should also be considered to ensure a prominent energy saving performance.
Marcin Nita - One of the best experts on this subject based on the ideXlab platform.
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structurally tailored carbon xerogels produced through a sol gel process in a water methanol Inorganic Salt Solution
Journal of Sol-Gel Science and Technology, 2011Co-Authors: Wojciech Kiciński, Mateusz Szala, Marcin NitaAbstract:The impact of solvent composition as well as Inorganic Salt content and type on carbon xerogel structure was investigated. Carbon xerogels were derived from the sol–gel polycondensation of resorcinol with furfural in a water–methanol–Inorganic Salt Solution. As Inorganic Salts, NaCl, NH4ClO4 and FeCl3 were used. In order to conduct an accurate examination of the carbon xerogel structures and textures, Inorganic Salts were removed prior to carbonization. The xerogel structures can be tailored according to the water/methanol ratio and, to a lesser extent, according to the Inorganic Salt content and type in the starting Solution. As a result, a significant amount of Salt can be introduced to the gel network of the desired structure. The morphology and physical properties of the organic xerogels, carbon xerogels and their composites were characterized by means of SEM, N2 sorption and XRD. It was found that samples derived from mixtures with FeCl3 manifest well developed mesoporosity and depleated microporosity in comparison to samples prepared from mixtures with NaCl and NH4ClO4. Iron ions chemically bond to the xerogel matrix and cause its partial graphitization during the carbonization process, resulting in enhanced mesoporosity.
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Structurally tailored carbon xerogels produced through a sol–gel process in a water–methanol–Inorganic Salt Solution
Journal of Sol-Gel Science and Technology, 2010Co-Authors: Wojciech Kiciński, Mateusz Szala, Marcin NitaAbstract:The impact of solvent composition as well as Inorganic Salt content and type on carbon xerogel structure was investigated. Carbon xerogels were derived from the sol–gel polycondensation of resorcinol with furfural in a water–methanol–Inorganic Salt Solution. As Inorganic Salts, NaCl, NH4ClO4 and FeCl3 were used. In order to conduct an accurate examination of the carbon xerogel structures and textures, Inorganic Salts were removed prior to carbonization. The xerogel structures can be tailored according to the water/methanol ratio and, to a lesser extent, according to the Inorganic Salt content and type in the starting Solution. As a result, a significant amount of Salt can be introduced to the gel network of the desired structure. The morphology and physical properties of the organic xerogels, carbon xerogels and their composites were characterized by means of SEM, N2 sorption and XRD. It was found that samples derived from mixtures with FeCl3 manifest well developed mesoporosity and depleated microporosity in comparison to samples prepared from mixtures with NaCl and NH4ClO4. Iron ions chemically bond to the xerogel matrix and cause its partial graphitization during the carbonization process, resulting in enhanced mesoporosity.
E. Weingartner - One of the best experts on this subject based on the ideXlab platform.
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Widening the gap between measurement and modelling of secondary organic aerosol properties
Atmospheric Chemistry and Physics, 2010Co-Authors: N. Good, David Topping, J. Duplissy, M. Gysel, A. Metzger, U. Baltensperger, Z. Ristovski, Nicholas Meyer, S. Turner, E. WeingartnerAbstract:Abstract. The link between measured sub-saturated hygroscopicity and cloud activation potential of secondary organic aerosol particles produced by the chamber photo-oxidation of α-pinene in the presence or absence of ammonium sulphate seed aerosol was investigated using two models of varying complexity. A simple single hygroscopicity parameter model and a more complex model (incorporating surface effects) were used to assess the detail required to predict the cloud condensation nucleus (CCN) activity from the sub-saturated water uptake. Sub-saturated water uptake measured by three hygroscopicity tandem differential mobility analyser (HTDMA) instruments was used to determine the water activity for use in the models. The predicted CCN activity was compared to the measured CCN activation potential using a continuous flow CCN counter. Reconciliation using the more complex model formulation with measured cloud activation could be achieved widely different assumed surface tension behavior of the growing droplet; this was entirely determined by the instrument used as the source of water activity data. This unreliable derivation of the water activity as a function of solute concentration from sub-saturated hygroscopicity data indicates a limitation in the use of such data in predicting cloud condensation nucleus behavior of particles with a significant organic fraction. Similarly, the ability of the simpler single parameter model to predict cloud activation behaviour was dependent on the instrument used to measure sub-saturated hygroscopicity and the relative humidity used to provide the model input. However, agreement was observed for Inorganic Salt Solution particles, which were measured by all instruments in agreement with theory. The difference in HTDMA data from validated and extensively used instruments means that it cannot be stated with certainty the detail required to predict the CCN activity from sub-saturated hygroscopicity. In order to narrow the gap between measurements of hygroscopic growth and CCN activity the processes involved must be understood and the instrumentation extensively quality assured. It is impossible to say from the results presented here due to the differences in HTDMA data whether: i) Surface tension suppression occurs ii) Bulk to surface partitioning is important iii) The water activity coefficient changes significantly as a function of the solute concentration.
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Widening the gap between measurement and modelling ofsecondary organic aerosol properties
2010Co-Authors: N. Good, David Topping, J. Duplissy, M. Gysel, N. K. Meyer, A. Metzger, U. Baltensperger, Z. Ristovski, Samantha J. Turner, E. WeingartnerAbstract:The link between measured sub-saturated hygroscopicity and cloud activation potential of secondary organic aerosol particles produced by the chamber photo-oxidation of α-pinene in the presence or absence of ammonium sulphate seed aerosol was investigated using two models of varying complexity. A simple single hygroscopicity parameter model and a more complex model (incorporating surface effects) were used to assess the detail required to predict the cloud condensation nucleus (CCN) activity from the subsaturated water uptake. Sub-saturated water uptake measured by three hygroscopicity tandem differential mobility analyser (HTDMA) instruments was used to determine the water activity for use in the models. The predicted CCN activity was compared to the measured CCN activation potential using a continuous flow CCN counter. Reconciliation using the more complex model formulation with measured cloud activation could be achieved widely different assumed surface tension behavior of the growing droplet; this was entirely determined by the instrument used as the source of water activity data. This unreliable derivation of the water activity as a function of solute concentration from sub-saturated hygroscopicity data indicates a limitation in the use of such data in predicting cloud condensation nucleus behavior of particles with a significant organic fraction. Similarly, the ability of the simpler single parameter model to predict cloud activation behaviour was dependent on the instrument used to measure sub-saturated hygroscopicity and the relative humidity used to provide the model input. However, agreement was observed for Inorganic Salt Solution particles, which were measured by all instruments in agreement with theory. The difference in HTDMA data from validated and extensively used instruments means that it cannot be stated with certainty the detail required to predict the CCN activity from sub-saturated hygroscopicity. In order to narrow the gap between measurements of hygroscopic growth and CCN activity the processes involved must be understood and the instrumentation extensively quality assured. It is impossible to say from the results presented here due to the differences in HTDMA data whether: i) Surface tension suppression occurs ii) Bulk to surface partitioning is important iii) The water activity coefficient changes significantly as a function of the solute concentration.
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Widening the gap between measurement and modelling of secondary organic aerosol properties?
2009Co-Authors: N. Good, D. O. Topping, J. Duplissy, M. Gysel, N. K. Meyer, A. Metzger, S. F. Turner, U. Baltensperger, Z. Ristovski, E. WeingartnerAbstract:Abstract. The link between measured sub-saturated hygroscopicity and cloud activation potential of secondary organic aerosol particles produced by the chamber photo-oxidation of α-pinene in the presence or absence of ammonium sulphate seed aerosol was investigated using two models of varying complexity. A simple single hygroscopicity parameter model and a more complex model (incorporating surface effects) were used to assess the detail required to predict the cloud condensation nucleus (CCN) activity from the sub-saturated water uptake. Sub-saturated water uptake measured by three hygroscopicity tandem differential mobility analyser (HTDMA) instruments was used to determine the water activity for use in the models. The predicted CCN activity was compared to the measured CCN activation potential using a continuous flow CCN counter. Reconciliation using the more complex model formulation with measured cloud activation required widely different assumed surface tension behavior of the growing droplet; this was entirely determined by the instrument used as the source of water activity data. This unreliable derivation of the water activity as a function of solute concentration from sub-saturated hygroscopicity data indicates a limitation in the use of such data in predicting cloud condensation nucleus behavior of particles with a significant organic fraction. Similarly, the ability of the simpler single parameter model to predict cloud activation behaviour was dependent on the instrument used to measure sub-saturated hygroscopicity and the relative humidity used to provide the model input. However, agreement was observed for Inorganic Salt Solution particles, which were measured by all instruments in agreement with theory. The difference in HTDMA data from proven instruments means that it cannot be stated with certainty the detail required to predict the CCN activity from sub-saturated hygroscopicity. In order to narrow the gap between measurements of hygroscopic growth and CCN activity the processes involved must be understood. It is impossible to say from the results presented here whether: i) Surface tension suppression occurs ii) Bulk to surface partitioning is important iii) The water activity coefficient changes significantly as a function of the solute concentration.
Wenhao Pu - One of the best experts on this subject based on the ideXlab platform.
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energy saving analysis for a Solution evaporation system with high boiling point elevation based on self heat recuperation theory
Desalination, 2015Co-Authors: W F He, Lin Liang, Wenhao PuAbstract:Abstract This paper focuses on the application of self-heat recuperation theory (SHRT) in mechanical vapor recompression (MVR) evaporation systems when used to concentrate Solutions with boiling point elevation (BPE). A nonlinear model is presented and used to analyze the advantages of heat recovery and multi-stage MVR over single-stage MVR. The model is then used to optimize the number of stages, evaporation temperatures, heat transfer temperature differences and stage concentration changes in relation to the compressor energy requirements. In comparison with single-stage MVR and conventional three-effect evaporation, multi-stage MVR with SHRT is shown to offer advantages when the number of stages is large, the evaporation temperatures are high and a large mass concentration difference between the outlet and inlet is required. However, the SHRT-based MVR system does not always yield energy savings when dealing with an Inorganic Salt Solution with high BPE. A case study on concentrating a calcium chloride Solution indicates that the SHRT-based MVR system uses more energy when the inlet mass fraction is over 38% compared to the conventional three-effect evaporation technology.
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Analysis of energy saving for ammonium sulfate Solution processing with self-heat recuperation principle
Applied Thermal Engineering, 2014Co-Authors: W F He, Wenhao Pu, Lin LiangAbstract:Abstract As an important production process, the evaporative concentration of the Inorganic Salt Solution is extensively applied in the industry, and it is significant to investigate the energy saving potential of such evaporation systems. In the paper, taking the ammonium sulfate Solution for example, the self-heat recuperation technology (SHRT) is utilized to design two mechanical vapor recompression (MVR) systems, and the relevant energy saving performance is analyzed. It is found that the designed systems, which are satisfied with SHTR, enable the recovery of the sensible and latent heat of the emission Solution without any additional heat, and compared to the conventional three-effect evaporation system, the energy saving performance are more prominent. However, in view of the existence of the boiling point elevation (BPE) for the Inorganic Salt Solution, a maximum reduction amplitude of 40% of the energy saving performance for the double-stage MVR system is obtained compared with the single-stage MVR system. As a result, it is concluded that the only satisfaction to the SHRT is not enough, and the pattern of the MVR system should also be considered to ensure a prominent energy saving performance.