Abstract:
A milk pasteurization system was developed by utilizing solar thermal energy for off-grid periods
of rural or urban milk products. This work sited on the warm climate condition of Doyogena.
Doyogena is located in Kambata Zone, S.N.N.P.R ., Ethiopia. The milk pasteurization process
consumes a huge amount of energy, using solar energy for the pasteurization process decreases
the required conventional energy. While milk is a perishable food item and needs careful
handling from source to supply. Unreliable handling of milk creates harmful pathogen and
spoilage microorganisms and milk-borne diseases in developing countries especially in Ethiopia
leads to millions of deaths and billions of illnesses annually. Milk producers in Doyogena, the
study area not used any milk preservation systems. Therefore milk pasteurization system is one
of several interventions that can improve public health.
The purpose of this work is to analyze the performance of the solar energy-based system for the
small-scale milk pasteurization process with a low-cost helical tube heat exchanger immersed in
the milk storage tank. The effectiveness of the milk pasteurization system has been studied using
CFD (computational fluid dynamics).
The system uses 2.42
the gross area of an inclined evacuated tube solar collector and the
solar radiation intensity on the inclined surface of the location has been analyzed from available
solar data. The monthly average useful energy received by the collector ranges from 650Wh/
to 10720Wh/ and the maximum hot water temperature exit from the collector ranges from
79 to 82.32 using water as heat transfer fluid(HTF). Energy loss by convection heat
transfer to ambient, the hot water temperature in the thermal storage tank (inlet to the helical
tube heat exchanger) found to be 70 to 78 which above the required pasteurization
temperature ranges from 65.5 to 69 . Overall results indicate that solar-based milk
pasteurization system was viable technology in this manner and it achieved the acceptable milk
temperature range being heated to kill microorganisms that leads to milk spoilage. I am
recommended using an integrated storage system to optimize the system for large-scall milk
pasteurization
