Page 367 - Applied Process Design For Chemical And Petrochemical Plants Volume III

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324 Applied Process Design for Chemical and Petrochemical Plants

Table 11-6 (continued)
Genetron CFC and HCFC Types of Refrigerants Indicating Substitution “Phasing-Out” of Selected Compounds
®
with Newer Replacement Compounds

Difluoromethane Chlorodifluoro- Azeotrope Pentafluoroethane Chlorodifluoro- Azeotrope
Pentafluoroethane methane (CHClF 2 /CClF 2 CF 3 ) Trifluoroethane methane (CHF 2 CF 3 /CH 3 CF 3 )
Tetrafluoroethane Pentafluoroethane An azeotropic mix- Tetrafluoroethane Pentafluoroethane AZ-50 is a non-
(CH 2 F 2 /CHF 2 CF 3 / Trifluoroethane ture used in low- (CHF 2 CF 3 /CH 3 CF 3 / Propane ozone-depleting
CF 3 CH 2 F) (CHClF 2 /CHF 2 CF 3 / and medium- CF 3 CH 2 F) (CHClF 2 /CHF 2 CF 3 / azeotropic mixture
A long-term, non- CH 3 CF 3 ) temperature A long-term, non- C 3 H 8 ) of HFC-125 and
ozone-depleting A interim replace- applications. ozone-depleting An interim replace- HFC-143a. It has
replacement for ment for retrofitting replacement for ment for R-502 used been primarily
HCFC-22 in various low- and medium- R-502 in low- mainly for ice designed to replace
air-conditioning temperature and medium- machines and soft R-502 in low-
applications, as well commercial temperature ice cream machines. and medium-
as in positive dis- refrigeration commercial temperature
placement refrigera- systems. refrigeration commercial refriger-
tion systems. It is a systems. ation applications
ternary blend of such as supermarket
HFC-32/HFC-125/ display cases and ice
HFC-134a. machines.

Selected Blend Blend Azeotrope Blend Blend Azeotrope
Physical Data 407C 408A 502 404A HP81 AZ-50
Substitutes (see legend)
ASHRAE number R-407C R-408A R-502 R-404A R-402B R-507
Molecular weight 86.2 87.7 111.6 97.6 94.7 98.9
Boiling point @ 1 atm, (°F) 46.4 49.0 49.8 51.0 52.5 52.1
Freezing point @ 1 atm, (°F) 256 — — — — 178
Critical temperature (°F) 189.1 201.1 180 162.3 180.7 160
Critical pressure (psia) 699.1 736.7 591 535.0 644.6 550
3
Saturated liquid density @ 86°F, (lb/ft ) 70.5 64.87 74.4 63.5 69.73 63.8
Specific heat of liquid @ 86°F (Btu/lb•°F)* 0.37 0.34 0.30 0.37 0.32 0.35
Specific heat of vapor @ constant pressure*
(Cp), @ 86°F and 1 atm, (Btu/lb•°F) 0.18 0.19 0.17 0.21 0.18 0.22
Flammable range, (based on ASHRAE
Standard 34 with match ignition)†† None None None None None None
ANSI/ASHRAE Standard 34-1992 safety
group classification A1/A1 A1/A1 A1 A1/A1 A1/A1 A1
NOTE: 502 is an NOTE: AZ-50 is
azeotropic an azeotropic
mixture mixture
consisting of consisting of
HCFC-22 HFC-125
LEGEND: (CHClF 2 ), 48.8% (CHF 2 CF 3 ), 50%
by weight and by weight and
CFC 11 Substitutes CFC 115 HFC-143a
CFC 12 Substitutes (CClF 2 CF 3 ), (CH 3 CF 3 ), 50%
51.2% by weight. by weight. U.S.
R-502 Substitutes
Patent 5,211,867
CFC 13/R-503 Substitutes AlliedSignal Inc.
HCFC 22 Substitutes

*Preliminary information based on estimated properties.

: Bubble point temperature.
†: Upper and lower vapor flammability (vol %).
††: ASTM E681-85 match ignition ambient conditions.
†††:N.C. not classified.
: @ 30°F.

Used by permission: Bul. G525-001, ©1998. AlliedSignal, Inc., Speciality Chemicals . ®