Comparison of Heat Transfer for R22 and some Alternatives in a 25 MW Shell-and-Tube Condenser
Paper in proceedings, 2000
Calculations have been carried out for a 25 MW horizontal shell-and-tube condenser with shell-side condensation, part of a heat pump for district heating. Due to a coming ban on refilling R22, which is used in some district heating heat pumps, calculations of heat transfer were carried out for R22, R134a and four zeotropic refrigerant mixtures, to see how well they perform. It was found that some of the refrigerant mixtures are competitive to R134a as replacement for R22.
Two comparisons were made, one for fixed duty and one for a fixed heat pump system. In both comparisons some of the mixtures seem to have better performance than R134a when considering duty and heat transfer whilst maintaining lower flow rates.