• Proceedings of the KSME Conference
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• 2000.04b
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• pp.228-233
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• 2000

An experimental study has been performed regarding heat and mass transfer in a falling film absorber of domestic small-sized absorption chiller/heater. Components were concentrically arranged in cylindrical form : from the center, with a series of low temperature generator, absorber and evaporator. The arrangement of such helical-typed heat exchangers allows to make the system more compact as compared to conventional one. Experimental measurements were conducted with a helical absorber using $LiBr+LiI+LiNO_3+LiCl$ and LiBr solutions. As a result, the heat and mass flux performance of $LiBr+LiI+LiNO_3+LiCl$ solution shows the tendency of $2{\sim}5%$ increase. Therefore, $LiBr+LiI+LiNO_3+LiCl$ solution can be taken consideration into applying to small-sized absorption chiller/heater because of using without crystal through high concentration as 4wt% comparing with LiBr solution.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.400-406
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• 1999

In an effort to obtain high efficiency in gas fired absorption chillers, a new working fluid has been developed with thc addition of the component of $LiNO_3$, LiCl and LiI to the conventional solution of $LiBr-H_2O$. The solubility and vapor pressure of the 4 component working fluid developed in this work were measured and compared to the results of $LiBr-H_2O$ solution. It was observed that there exists an optimal mole ratio of the inorganic salts in terms of solubility. The mole ratio of LiBr, $LiNO_3$ and LiCl was found to be around 5:1:1~2 in the $LiBr-LiNO_3-LiCl-H_2O$ mixture, and in the case of $LiBr-LiO_3-Lil-H_2O$ and $LiBr-Lil-LiCl-H_2O$ mixtures, the mole ratio of LiBr, $LiNO_3$ and Lil/ LiBr, LiI and LiCl were found to be around 5:1:1 and 5:1:0.5~1 respectively. The vapor pressure of the 4 component working fluid of the optimal mole ratio was increascd with adding the component of $LiNO_3$, LiCl and LiI except for $LiBr-LiNO_3-LiCl-H_2O$ mixture. The absorption capacity of $LiBr-LiNO_3-LiCl-H_2O$ mixture was obtained higher than that of $LiBr-H_2O$ mixture.

• Journal of Energy Engineering
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• v.7 no.2
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• pp.231-240
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• 1998

The global environmental problems such as CFC, energy losses in heat recovery system as well as summer peak time power demands, the development of high efficiency absorption refrigeration systems is one of the most promising method in this problems. The absorption refrigeration system to utilize treated sewage is available for environmental protection and energy conservation. Simulation analysis on the double-effect absorption refrigeration cucles with parallel or series flow type has been performed. LiBr+LiI+LiCl+LiNO$_3$ solution was selected as the new working fluid. The main purpose of this study is evaluating the possibilities of effective utilization of treated sewage as a cooling water for the absorber and condenser. The other purpose of the present study is to determine the optimum designs and operating conditions based on the operating constraints and the coefficient of performance in the parallel or series flow type. In this study, we found out the characteristic of new working solution through the cycle simulation and compared LiBr solution to evaluate. The absorption refrigeration machine using the new working fluid was obtained better results COP rise and compactness of system by comparison with LiBr solution.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.1 no.3
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• pp.219-227
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• 1989

Performance analysis of an absorption heat pump system for solar energy recovery has been done by computer simulation to find improved working pairs. Based on the thermodynamic analysis, the coefficient of performance and mass flow ratio have been calculated to compare two aqueous solutions [LiCl-water, $LiCi-CaCl_2-Zn(NO_3)_2$-water] which were developed for cooling by others, with the conventional LiBr-water solution. As a result of this analysis, the performances of the new aqueous solutions were found to be better than that of LiBr-water solution not only in cooling systems, but also in heating and in heat transformer systems. Their theoretical thermodynamic performance data were given here with.

• Journal of the Korean Chemical Society
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• v.40 no.4
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• pp.243-248
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• 1996

New routes have been developed for the practical syntheses of dl-Muscone(1) employing cyclopentadecanone(2) as the starting material. In this experiment, addition of bromine to cyclopentadecanone in dried E. Ether solution with a trace of $AlCl_3$ as the catalyst were produced 2-bromocyclopentadecanone(3). This process was enhanced formation of regioselective enolate anion at $C_2$ position. 2-Bromocyclopentadecanone was put into $Li_2CO_3$-LiBr-DMF solution at 140∼150$^{\circ}C$, were produced trans- and cis-2-cyclopentadecen-1-one(4) mixture. Other by-products were reduced by control of reaction temperature and time. Trans- and cis-2-cyclopentadecen-1-one(4) mixture was directly put into dried E. Ether solvent and induce to react dropwise with $CH_3MgBr-Cu_2Cl_2$ complex, all of them got into 1,4-addition, dl-Muscone (1) was formed as the result. Conculsion, through three steps procedure from cyclopentadecanone(2) to dl-Muscone(1), the pure dl-Muscone was obtained with the high proportion of 85%, and synthetic cost was able to be much lower than any other conventional methods as there were no chemical separating steps.