文档介绍：Replacement Refrigerants for
Water Chillers
Ian Maclaine-cross
The University of New South Wales
Contact Address:
School of Mechanical and Manufacturing Engineering
The University of New South Wales
Sydney, NSW, 2052, AUSTRALIA
Phone: +61 2 9385 4112 Fax: +61 2 9663 1222
E-mail: -******@
ABSTRACT
The Montreal Protocol requires large water chillers cease using refrig-
erants 11, 22 and 123. Comparing thermodynamic and transport property pa-
rameters for these, 134a, 290, 601, 601a, 717 and pentafluoroiodoethane avoids
certain errors and biases. The parameters for R717 (ammonia) offer energy sav-
ings about 20%. R290 or 717 can replace 22. The pentane mixture R601/601a
[50/50] with an electronic 38% rotor speed increase can economically replace
R11.
Keywords: chillers, air conditioning, refrigerant, ammonia, hydrocarbon.
ENVIRONMENTAL IMPACTS
6
liquid 3 vapour 2
Water is such an effective and economical heat transfer condenser
fluid that almost all large air conditioning plant pressor
£ C
on pression uses packaged water chillers. Ta- high pressure £ C
@   valve
ble 1 list the two most popular chiller refrigerants and @  £ C
  @ low pressure £ C
potential replacements in order of direct environmental £ C
impact. The Montreal Protocol to protect the strato-
-evaporator -
spheric ozone layer requires all sign