Semi-welded heat exchangers can increase the COP of industrial ammonia/NH3 (R717) heat pumps by raising the evaporation temperature of the refrigerant on the cold side and lowering the condensing temperature on the hot side.
This was the message from Tommy Ångbäck, Sales Director for Refrigeration for Swedish manufacturer Alfa Laval, in a webinar at the online ATMO World Summit on March 30. The World Summit was organized by ATMOsphere (formerly shecco).
“In general it is possible to obtain a 2K closer approach with semi-welded plate heat exchangers compared to other technologies with comparable size and cost,” Ångbäck explained, stressing that for each degree (K) higher evaporation temperature on the cold side, the ammonia heat pump can save 3–6% in power consumption.