Milk storage system for remote areas using solar thermal energy and adsorption cooling

As there is a time gap between milking and storage, milk spoilage is more in remote areas in India, hence, immediate pasteurization and storing facility is required. For pasteurization heating is compulsory. In India most villages face scarcity of electricity, hence, solar and biomass heat (easily available) is a good option for milk pasteurization. After the pasteurization process for storing (150Ltrs of milk) in low temperature till its distribution, adsorption refrigeration is proposed here as it is run by solar/ waste heat or biogas (easily available from farm waste). During milk heating and storing at low temperature, materials used for containers and piping have chosen stainless steel (SS316), so that materials should not react with milk. For pasteurization of milk, one parabolic collector has been designed and developed. The result shows that at 5LPM flow rate, milk can be easily heated at 75 °C for 30 min. For storing 150ltrs of milk at 15-20 °C for 10-12 hrs, a solar power (flat plate collectors 8 m2) adsorption refrigeration has been designed and discussed. For adsorption refrigeration, selection of adsorption pair is very important. After reviewing different literatures, here activated carbon and methanol have chosen and justified. The experimental result shows that for 400LPH hot water supplied at 90 °C (desorber bed temperature at 80 °C), 35 °C condenser temperature and evaporator temperature 5 °C system's specific cooling power varies between 5.7 kW/kg to 5.4 kW/kg (variation due to uncertainty analysis) which is sufficient for storing 150ltrs of milk.