PDF Publication Title:
Text from PDF Page: 020
The trade name for the CO2 in the refrigeration industry is R744, where R is for refrigerant application and the number 7 indicates the refrigerant family (Natural refrigerant) and the last two digits 44 shows the molecular weight of CO2. The refrigerant CO2 used in the refrigeration industry is basically a waste product of various industrial processes, and is extracted and processed by different companies to be used as refrigerant. 2.2.1 History of CO2 CO2 is an old refrigerant and it is one of those which were used in the early application right after the start of refrigeration industry. J&E Hall a British company, made the first two stage CO2 machine in 1889. CO2 was used in diverse applications and the most important application area at that time was marine refrigeration where other refrigerants (like ammonia) could not be used due to flammability and toxicity problems. Commonly stated problems at that time were, High pressure containment with the available technology at that time. Low COP and capacity loss at high heat rejection pressures. Old working fluids were replaced by CFC’s which were introduced in 1930’s and 1940’s, they were considered more safe than ammonia and SO2. Factors like low working pressure, better efficiency, low cost assembly and aggressive marketing of CFC’s replaced CO2 as well. As the problems associated with the CFC’s (Ozone Depletion) become clear, again there was search for reliable refrigerants. In 1989 Professor Gustav Lorentzen devised a system utilizing transcritical CO2 cycle, one promising application for that system was found in automobile air conditioning (a dominant sector in refrigerant emission) which needs a non-toxic and non flammable refrigerant. Professor Lorentzen compared the performance of CO2 with R-12 and although CO2 was less efficient but several practical considerations made the actual efficiencies of the two systems to be comparable. These were the results found by Professor Lorentzen and others which again raised interest in CO2 as refrigerant, now a number of research projects (both from industry and research sectors) are in process. 8PDF Image | heat recovery from R744 based refrigeration system
PDF Search Title:
heat recovery from R744 based refrigeration systemOriginal File Name Searched:
r744-heat-recovery.pdfDIY PDF Search: Google It | Yahoo | Bing
CO2 Organic Rankine Cycle Experimenter Platform The supercritical CO2 phase change system is both a heat pump and organic rankine cycle which can be used for those purposes and as a supercritical extractor for advanced subcritical and supercritical extraction technology. Uses include producing nanoparticles, precious metal CO2 extraction, lithium battery recycling, and other applications... More Info
Heat Pumps CO2 ORC Heat Pump System Platform More Info
| CONTACT TEL: 608-238-6001 Email: greg@infinityturbine.com | RSS | AMP |