Investigation of the performance characteristics of an ammonia-water absorption chiller in a tri-generation system arrangement

Trigeneration systems have been used in a number of applications including commercial buildings and industrial facilities. Most of these have been for space cooling applications with a smaller number for refrigeration applications in the food processing industry which requires temperatures below 0oC. This paper is concerned with the investigation and development of modular trigeneration systems for food industry applications based on the integration of microturbines and ammonia water absorption refrigeration systems. Specifically, the paper presents results of experimental investigations on the performance of a 12 kW capacity ammonia-water absorption refrigeration system driven by thermal energy recovered from the exhaust gases of a microturbine in a trigeneration arrangement. The heat transfer between the microturbine exhaust heat exchanger and the generator of the absorption refrigeration system is performed by a heat transfer fluid in a closed heat transfer loop. Tests were performed at different brine temperatures and heat transfer fluid temperatures. The performance of the unit was evaluated and found to compare favourably with the performance of a directly gas fired absorption chiller. In addition, the overall efficiency of the trigeneration system was also evaluated.