In order to effectively recover low and medium grade heat energy,a novel combined cooling and heating storage system based on zeolite-water is proposed in this paper.The system coupled the zeolite-water adsorption pro...In order to effectively recover low and medium grade heat energy,a novel combined cooling and heating storage system based on zeolite-water is proposed in this paper.The system coupled the zeolite-water adsorption process with the water evaporation refrigeration process during discharging process to realize generating cold energy and heat energy simultaneously.A more accurate kinetic model of zeolite and water adsorption is developed,and the thermodynamic performance of discharging process of the system is numerically analyzed.The results show the system has the higher energy conversion coefficient of 1.49 and the higher energy density of 1216.6 kJ/kg-zeolite.The change laws of system performances,such as energy generated,energy conversion coefficient and energy density,with key parameters during discharging process are revealed.The study provides a way for efficient utilization of low and medium grade heat energy.展开更多
Large amounts of waste heat below 100oC from the industrial sector are re-leased into the atmosphere. It has been suggested that energy system efficiency can be increased with adsorption chillers. However, the cooling...Large amounts of waste heat below 100oC from the industrial sector are re-leased into the atmosphere. It has been suggested that energy system efficiency can be increased with adsorption chillers. However, the cooling power and coefficient of performance (COP) of conventional adsorption chillers significantly decrease with the desorption temperature. In this paper, we proposed a mechanical booster pump (MBP)-assisted adsorption chiller cycle, and evaluated its performances. In the cycle, a MBP was incorporated into a zeolite-water-type adsorption chiller for facilitating water vapor transportation between an adsorber and an evaporator/condenser. We have experimentally studied the effect of the input electrical power of MBP on the performances of adsorption chiller cycle. It has been demonstrated that the heat input achieved by using MBP at the desorption temperature of 50oC was 1.6 times higher than that of without MBP at the desorption temperature of 60oC. And the increase of pump power was found to be effective in increasing the heat input. Therefore, it was confirmed that the operation range of desorption temperature, which can be generated by using the waste heat, was extended and the cooling power was increased directly by using MBP.展开更多
This work concerns a dynamic modeling and a numerical simulation of the operation of an adsorption solar refrigeration system using the zeolite-water couple. For this, a mathematical model representing the evolution o...This work concerns a dynamic modeling and a numerical simulation of the operation of an adsorption solar refrigeration system using the zeolite-water couple. For this, a mathematical model representing the evolution of heat and mass transfer at each component of the solar adsorption refrigerator has been developed. We have adopted the Dubinin-Astakhov model for the adsorption kinetics of the zeolite/water pair. This model allows to describe the phenomenon of adsorption and to calculate the rate of adsorbate (water) in the zeolite (adsorbent) as a function of the temperature and the pressure. The equations governing the operation of the solar adsorption refrigerator, deduced from the thermal and mass balances established at the collector adsorber, condenser and evaporator components, were solved by an implicit finite difference scheme and Gauss Seidel’s iterative method. We have validated the model established by applying it to the model of Allouhi et al. 2014. We analyzed the influence of the adsorbate/adsorbent couples, the solar flux, the ambient temperature on the adsorption and desorption process. The temperature profiles obtained representing the temperature evolution of the glass, the absorbent plate, the zeolite-water mixture, the condenser, the evaporator, as well as the pressure and the adsorbed mass allowed us to evaluate the performance of the solar adsorption refrigerator. SCOP is higher the higher the solar flux captured by the collector-adsorber.展开更多
High silica zeolite Y has been positively evaluated to clean-up water polluted with sulfonamides, an antibiotic family which is known to be involved in the antibiotic resistance evolution. To define possible strategie...High silica zeolite Y has been positively evaluated to clean-up water polluted with sulfonamides, an antibiotic family which is known to be involved in the antibiotic resistance evolution. To define possible strategies for the exhausted zeolite regeneration,the efficacy of some chemico-physical treatments on the zeolite loaded with four different sulfonamides was evaluated. The evolution of photolysis, Fenton-like reaction, thermal treatments, and solvent extractions and the occurrence in the zeolite pores of organic residues eventually entrapped was elucidated by a combined thermogravimetric（TGA–DTA）, diffractometric（XRPD）, and spectroscopic（FT-IR） approach. The chemical processes were not able to remove the organic guest from zeolite pores and a limited transformation on embedded molecules was observed. On the contrary, both thermal treatment and solvent extraction succeeded in the regeneration of the zeolite loaded from deionized and natural fresh water. The recyclability of regenerated zeolite was evaluated over several adsorption/regeneration cycles, due to the treatment efficacy and its stability as well as the ability to regain the structural features of the unloaded material.展开更多
基金This study is financially supported by National Key R&D Plan(Grant No.2017YFB0903605)the National Science Fund for Distinguished Young Scholars(Grant No.51925604)+2 种基金International Partnership Program,Bureau of International Cooperation of Chinese Academy of Sciences(Grant No.182211KYSB20170029)Transformational Technologies for Clean Energy and Demonstration,Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDA21070302)Beijing Key Laboratory of Distributed Combined Cooling Heating and Power System.
文摘In order to effectively recover low and medium grade heat energy,a novel combined cooling and heating storage system based on zeolite-water is proposed in this paper.The system coupled the zeolite-water adsorption process with the water evaporation refrigeration process during discharging process to realize generating cold energy and heat energy simultaneously.A more accurate kinetic model of zeolite and water adsorption is developed,and the thermodynamic performance of discharging process of the system is numerically analyzed.The results show the system has the higher energy conversion coefficient of 1.49 and the higher energy density of 1216.6 kJ/kg-zeolite.The change laws of system performances,such as energy generated,energy conversion coefficient and energy density,with key parameters during discharging process are revealed.The study provides a way for efficient utilization of low and medium grade heat energy.
文摘Large amounts of waste heat below 100oC from the industrial sector are re-leased into the atmosphere. It has been suggested that energy system efficiency can be increased with adsorption chillers. However, the cooling power and coefficient of performance (COP) of conventional adsorption chillers significantly decrease with the desorption temperature. In this paper, we proposed a mechanical booster pump (MBP)-assisted adsorption chiller cycle, and evaluated its performances. In the cycle, a MBP was incorporated into a zeolite-water-type adsorption chiller for facilitating water vapor transportation between an adsorber and an evaporator/condenser. We have experimentally studied the effect of the input electrical power of MBP on the performances of adsorption chiller cycle. It has been demonstrated that the heat input achieved by using MBP at the desorption temperature of 50oC was 1.6 times higher than that of without MBP at the desorption temperature of 60oC. And the increase of pump power was found to be effective in increasing the heat input. Therefore, it was confirmed that the operation range of desorption temperature, which can be generated by using the waste heat, was extended and the cooling power was increased directly by using MBP.
文摘This work concerns a dynamic modeling and a numerical simulation of the operation of an adsorption solar refrigeration system using the zeolite-water couple. For this, a mathematical model representing the evolution of heat and mass transfer at each component of the solar adsorption refrigerator has been developed. We have adopted the Dubinin-Astakhov model for the adsorption kinetics of the zeolite/water pair. This model allows to describe the phenomenon of adsorption and to calculate the rate of adsorbate (water) in the zeolite (adsorbent) as a function of the temperature and the pressure. The equations governing the operation of the solar adsorption refrigerator, deduced from the thermal and mass balances established at the collector adsorber, condenser and evaporator components, were solved by an implicit finite difference scheme and Gauss Seidel’s iterative method. We have validated the model established by applying it to the model of Allouhi et al. 2014. We analyzed the influence of the adsorbate/adsorbent couples, the solar flux, the ambient temperature on the adsorption and desorption process. The temperature profiles obtained representing the temperature evolution of the glass, the absorbent plate, the zeolite-water mixture, the condenser, the evaporator, as well as the pressure and the adsorbed mass allowed us to evaluate the performance of the solar adsorption refrigerator. SCOP is higher the higher the solar flux captured by the collector-adsorber.
基金co-funded by the Italian Ministry of Education, University, and Research (No. PRIN 2008 BL2NWK: Zeolites as nano-reactors for the environment: efficiency, selectivity and stability in the adsorption of drugs from contaminated waters)
文摘High silica zeolite Y has been positively evaluated to clean-up water polluted with sulfonamides, an antibiotic family which is known to be involved in the antibiotic resistance evolution. To define possible strategies for the exhausted zeolite regeneration,the efficacy of some chemico-physical treatments on the zeolite loaded with four different sulfonamides was evaluated. The evolution of photolysis, Fenton-like reaction, thermal treatments, and solvent extractions and the occurrence in the zeolite pores of organic residues eventually entrapped was elucidated by a combined thermogravimetric（TGA–DTA）, diffractometric（XRPD）, and spectroscopic（FT-IR） approach. The chemical processes were not able to remove the organic guest from zeolite pores and a limited transformation on embedded molecules was observed. On the contrary, both thermal treatment and solvent extraction succeeded in the regeneration of the zeolite loaded from deionized and natural fresh water. The recyclability of regenerated zeolite was evaluated over several adsorption/regeneration cycles, due to the treatment efficacy and its stability as well as the ability to regain the structural features of the unloaded material.
