• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.1
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• pp.34-41
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• 2004

The chemical heat pump based on the Dehydration/Hydration process with a MgO/$H_2O$ system has been researched. The reactor bed could be expected to store the heat around 200∼37$0^{\circ}C$ by the dehydration reaction and to release the heat around 100∼16$0^{\circ}C$ by the hydration reaction under the heat amplification mode operation. The heat output rate of the heat pump system was evaluated using the experimentally determined parameters. The results show that 6∼50 W/kg of heat output and 0.5∼0.8 of heat recovery ratio are attainable. The heat pump will be applicable for a load leveling in a co-generation system by chemical storage of surplus heat at low heat demand and by supplying heat in the peak load period.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1993.11a
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• pp.78-81
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• 1993

AN EXTENSIVE RESEARCH AND DEVELOPMENT WORK WILL BE CARRIED OUT FOR THE COMMERCIALIZATION OF THE CHEMICAL HEAT PUMP SYSTEM WHICH BASED ON THE ELF AQUITAINE FRANCE PATENTED AND KIME LICENSED SOLID/GAS CHEMICAL REACTION TECHNOLOGY. TOWARD ON THAT GOAL, THE BASIC AND ENGINEERING DETAILS SUCH AS IMPEX BLOCK MATERIAL, PHYSICO-CHEMICAL AND THERMO-CHEMICAL CHARACTERISTICS OF REACTION MECHANISMS IN THE SOLID/GAS CHEMICAL REACTION HEAT PUMP SYSTEMS. THREE KIND OF APPLICATION SYSTEM ARE NOW INVESTIGATED; AIR CONDITIONING, REFRIGERATOR AND INDUSTRIAL PROCESS HEATING AND COOLING SYSTEM.

• Journal of Hydrogen and New Energy
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• v.1 no.1
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• pp.24-30
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• 1989

Prototype metal hydride chemical heat pump was constructed using $LaNi_{4.7}Al_{0.3}$ for high temperature hydride and $MmNi_{4.15}Fe_{0.65}Al_{0.2}$ for low temperature hydride, and the effects of operating conditions on the performace of heat pump were investigaed to find out the optimum operating condition. Operating variables considered in this work were cycling time, temperature of hot air blown to the high temperature reactor, the amount of hydrogen gas with which the system was charged initially, and the flow rate of air at both reactors. Power of heat pump increases monotonically as $T_h$ increases, and shows maxima at 4.8H/M and 15-25 min in $H_2$ charged and cycling time respectively. Power of heat pump increases as air flow rate increases at low flow rate, but saturates to some value confined by heat flow rate through the hydride bed, These all phenomena can be explained by the modified power equation.

• 제어로봇시스템학회:학술대회논문집
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• 1991.10a
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• pp.1085-1090
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• 1991

Chemical heat pump is a system to upgrade the low level energy such as industrial waste heat and solar energy by using coupled endothermic and exothermic chemical reactions. Dehydrogenation of 2-propanol can absorb heat near 80.deg. C and is transformed into acetone and hydrogen. Hydrogenation of acetone can liberate heat near 200.deg. C. Dehydrogenation of 2-propanol is difficult around 80.deg. C because .DELTA.G has positive value, but dehydrogenation reaction in liquid phase can overcome this problem because vaporized acetone and hydrogen can be rapidly eliminated. In this work, dehydrogenation of 2-propanol was investigated in liquid phase with Raney nickel catalyst. The energy efficiency of the chemical heat pump was estimated by computer simulation.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.6 no.4
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• pp.406-416
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• 1994

In this study the reactor design procedure and method of solid-solid-gas chemical heat pump system using STELF technology were investigated. For manufacturing IMPEX block which is the kernel of reactor, proper salt pair should be selected, and equilibrium temperature drop and COP should be examined for selected salt pair. Moreover, apparent density, residual porosity, and graphite ratio should be calculated to give minimum block volume and mass, and maximum energy density without causing heat and mass transfer problems. Since heat exchange area can be changed with operating condition, reactor diameter, length, and stainless steel thickness should be decided for desired specifications. These procedure and method were applied to the case study of 6kW cold production and 8 hours storage capacity reactor.

• Journal of Energy Engineering
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• v.15 no.4 s.48
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• pp.284-290
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• 2006

The improvement of energy recovery is mandatory to decrease consumption of fossil fuels and to minimize negative impacts on the environment which originates from large cooling and heating demand. The absorption heat pump technology has a large potential for energy saving in this respect. Absorption heat pump is a means to upgrade waste heat without addition of extra thermal energy. In this study, resorption heat pump for energy recovery has been investigated using methanol-glycerine. The simulated calculation of theoretical thermal efficiency was performed based on the thermodynamic properties of the working fluid over various operating conditions. The thermal efficiency of higher than 0.4 was obtained by raising industrial waste heat, $70{\sim}80^{\circ}C$, by $40^{\circ}C$ in this system.

• Journal of Energy Engineering
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• v.6 no.1
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• pp.87-95
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• 1997

A chemical heat pump based on the reversible reactions between metal chlorides and ammonia gas is attractive alternative to compression system and liquid absorption systems in cooling and refrigerating fields. The advantages of chemical heat pump are no regulatory constants due to CFC refrigerants, utilization of gas, industrial waste heat, electricity, fuel oil etc. as heat sources and wide applications to energy storage system, large-scale energy managements for industrial process. The scale-up of chemical heat pump from laboratory prototype to pilot plants necessitates the interpretation of system performance and evaluation of dynamic behavior in the chemical reactor. This study contains the prediction of performance of chemical refrigerator according to operating condition, the dynamic simulations through reactor modelling, which is used for the calculation of reactive medium temperature and the conversion variation with reactor cooling temperature, and the effect survey of block parameters on the power of refrigerator.

• Journal of the Korean Society of Industry Convergence
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• v.8 no.4
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• pp.191-196
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• 2005

This study was carried out to investigate the heat storage/release characteristics of the thermochemical reaction of the calcined dolomite with the packed bed shape experimental apparatus for development of chemical heat pump system. In the present study, it was found that MgO of the calcined dolomite was not hydrated during the hydration process under the experimental conditions. Therefore, the MgO of the calcined dolomite can be regard as an inert material. As a result, it was found that all of CaO packed kept the reaction temperature of about $510^{\circ}C$ through the entire part of the bed. The dehydration reaction was incurred first at the wall side area as the supplied heat was transferred through the wall side into the packed bed. As a result of the temperature and concentration spread, the reaction was completed at the wall side progressed into the center.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.12
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• pp.1192-1203
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• 2005

A technical analysis was conducted to predict the development trend for heat pump system. The study was based on a submitted patent from 1983 to 2002 in Korea, U.S.A. and Japan. The total number of raw data from the registered database was 19,261 and the obtained data to be analyzed through the filtering process was 5,143. Technical development of compression type heat pump was more dominant than the other types, absorption, adsorption, and chemical heat pump. The patents for compression type made up over $80\%$ in each country, Most of patents were developed for the defrosting and controlling technology of the compression type heat pump system. Approximately $24\%\;and\;62\%$ of the patents about compression type heat pump were for defrosting and control technologies, respectively.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.22 no.5
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• pp.325-340
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• 1993