Experience in the Construction and Testing of a Solar-Powered Adsorptive Ice Maker

Abstract

The objective of this project is to study, construct and test the operation of the prototype of a solar-powered adsorptive ice maker that consists of 6 main components as adsorber-generator, receiver, water cool condenser, throttling device, evaporator and parabolic trough concentrator. The working pair is ammonia(refrigerant) and calcium chloride(adsorbent). A 1,500 Watt Tungsten halogen lamp is used as a heat source due to this project carried out during the rainy season. Adsorption Refrigeration cycle consists of 2 processes that are Regeneration process and Refrigeration process. The relation between temperature and pressure was studied. In the regeneration process, it is observed that when the temperature of the generator up to be about 45-50°C, the pressure in the system is about 20 barg, causing the condensation of ammonia vapor at the condenser . At the end of this process the liquid ammonia is collected in a receiver. The average condensation temperature and pressure are 26.4°C and 11.4 barg, respectively. In the refrigeration process, The liquid ammonia is throttled through the throttling valve to the evaporator where it evaporates by absorbing heat and provides useful cooling.

The test result shows that the lowest temperature obtained of the evaporator is about 9.0°C. In order to improve the system it is recommended that the reducing the number of coil and capacity of evaporator, increasing the refrigerant quantity or integrating blowers and air circulation systems be studied further so that the ice to form may be reached.