Patent ID: 7845190
Filing Date: 2010-12-07
Classification: F25B

Abstract:
1. A transcritical vapour compression refrigeration apparatus which comprises: a reciprocating refrigerant compressor, a gas cooler, an economiser, an evaporator and carbon dioxide (R-744); said compressor being operative to compress to supercritical pressure the carbon dioxide in two separate streams, said gas cooler being operative to reject heat from the compressed carbon dioxide at supercritical pressure in the gas cooler, said evaporator being operative to expand the cooled compressed carbon dioxide in a first stage to first temperature and pressure conditions in the economiser and further expanding said carbon dioxide in a second stage to second temperature and pressure conditions; said compressor being further operative to compress to supercritical pressure a stream of carbon dioxide from the economiser at said first temperature and pressure conditions to form a first stream in the compressor; and to compress to said supercritical pressure a second stream of carbon dioxide at said second temperature and pressure condition after having absorbed heat in the evaporator; said apparatus being further operative to combine said first and second compressed streams at said supercritical pressure before one of passing said combined streams to the gas cooler and passing said first and second streams through separate gas coolers before being combined.