ANALYSIS OF AN IMPROVED AQUA-AMMONIA ABSORPTION-REFRIGERATION CYCLE EMPLOYING EVAPORATOR BLOWDOWN TO PROVIDE RECTIFIER REFLUX

Increased concern over the continued availability of cheap oil and gas , combined with environmental concern relating to the large-scale comb ustion of fossil fuels has led to a renewal of interest in the absorpt ion refrigeration cycle. The aqua-ammonia cycle is particularly suitab le for applications in the process industries, where the refrigerant i s required to be at temperatures below 0 degrees C. A modification of the conventional cycle configuration is proposed and investigated The modified cycle employs liquid blowdown from the evaporator to provide reflux for the distillation-column generator. This modification can be employed to eliminate the use of fresh refrigerant, from the condense r, as reflux in the conventional aqua-ammonia absorption refrigeration cycle. Simulations of the modified cycle, using the PROCESS(TM) compu ter simulation package, predict an improvement in the coefficient of p erformance (COP) of approximately 5% coupled with a net reduction in t he total heat-transfer area required.