DEVELOPMENT OF A REFRIGERATION SYSTEM FOR COOLING MILK AT RURAL REGIONS

Morsi, M E. M.

doi:10.21608/mjae.2013.102048

DEVELOPMENT OF A REFRIGERATION SYSTEM FOR COOLING MILK AT RURAL REGIONS

Document Type : Original Article

Author

M E. M. Morsi

Researcher, Agric. Eng. Res. Inst., Agric. Res. Center Egypt.

10.21608/mjae.2013.102048

Abstract

The present paper presents an experimental evaluation of a solar refrigerator, prototype, based on an intermittent thermodynamic cycle of adsorption, using milk as refrigerant and the mineral zeolite as adsorber. This system uses a mobile adsorber, which is regenerated out of the refrigeration cycle and no condenser is applied. Because the solar regeneration is made in the ambient air for the regeneration, a SK14 solar cooker is considered. The cold chamber, with a capacity of 4 liters, is aimed for cooling milk. The objective is to analyze the advantages and disadvantages of the eventual use of this refrigerator in rural regions of Egypt, where no electricity is available. On the bases of the results obtained, a new prototype of refrigerator for rural regions is designed, based on the same thermodynamic cycle, but including changes in design and operation. According to the experiments Zeolite pan size of 2*20*25 cm proved to be the most optimum, it is the size recommended for use in milk cooler. According to the results of the mathematical modeling of drying of zeolite, the best describing the drying characteristic is Wang and Singh model. The regression equation R (correlation coefficient) indicates the degree of association between the observed and predicted values coefficient of efficient (C_e) was 0.999.

Main Subjects

Processing Engineering of Agricultural Products

References

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