Semi-GAX cycles for waste heat powered refrigeration [absorption heat pumps]

Waste heat powered absorption refrigeration is an economical and environmentally beneficial means of providing refrigeration. When the temperature is too low to power a conventional single effect absorption cycle, the double-lift cycle is needed. This paper describes several recently conceptualized double-lift cycles that incorporate internal heat exchange between the intermediate pressure absorber and the high pressure generator (termed semi-GAX). Computer modeling identified their key performance parameters. Compared to conventional double-lift cycles, the semi-GAX cycles enjoy a 20% increase in coefficient of performance, and require less total heat duty, implying lower first cost.