Development of Solar Based Vapour Compression In Situ Milk Cooling System

Abstract

India is the largest milk producer. Most of the milk is produced by animals reared by small and marginal farmers. In most of the remote villages where dairy farming is done, there are poor transportation facilities to transport milk to the processing plants. The milk obtained during the morning session is transported to the milk processing plant during the day, and similarly, the evening milk is taken to the milk plants in late evening. This results in high expenditure for the farmers as they have to transport the milk twice a day. The raw milk obtained from dairy farm spoils within 5 h, if appropriate, cooling is not done. In many villages with dairy farms do not have access to electricity or a very limited power supply. Thus, milk quality affected due to insufficient refrigerating facilities and irregular power supply. A solar based vapour compression in-situ milk cooling systems of 40 l storage capacity was developed. The system consisting of three solar panels, battery and an inverter. The performance of developed cooling system was evaluated for three capacities (10, 25 and 40 l) at agitator speed of 0, 18, 36 and 54 rpm to know the cooling time, energy consumption and COP. The quality of milk stored in the cooler was compared with milk stored in ambient condition. The cooling time of 10, 25 and 40 l milk at agitation speeds of 0, 18, 36 and 54 rpm were varied from 68-75 min, 96-102 min and 116-124 min, respectively. The total energy consumed per day for cooling of milk was ranged from 1.14 to 1.88 kWh. Contd..... newline