scroll compressors for propane (r290)
TRANSCRIPT
Scroll Compressor for Propane (R290)
Bachir Bella
2 2
Contents
Why Propane (R290)
Binomial Refrigerant/System Architecture (F-gas)
Variable Speed Scroll with Propane
Regulation and Standards for Propane
3 3 3
Why Propane: Efficient Future Proof Option But Some Limitations Exist
Regulatory
• Very low GWP
• Future Proof Refrigerant
• Natural Alternative To CO2 With GWP=3
Properties & Performance
• Up to -20% Lower Capacity
• But Up to 30% Higher COP
• Discharge Temperature comparable to R404A
Limitations
• Flammability / Hazardeous
• R290 Is Less Addressed In The Standards (IEC)
But Under Revision
• Directives (ATEX) & Standards Not Fully
Harmonized
• Directives & Regional Legislations Not Aligned
• Various Level Of Expertise In Different Channels
Advantage of Propane
• No Temperature Glide during constant pressure
phase change
• Up to -50% Lower system charge (lower liquid
density) compared to R404A & R407C
• Wide application range (NBT = -42.2°C, Tcrit. =
96.7°C)
• Moderate working pressure pcrit.= 42.6 bar
4 4
Hermetic Sealed
R290
HFO GWP <150
R404A
R407A/F
HFO R290
R450A,R513A
R448A/R449A/R134a
Indirect Systms
R450A, R513A,
R448A, R449A,
R134a, R407A/F
Non Hermetic Sealed
ENTR Lot. 1
For condensing
Units
Commercial Refrigeration System Architecture & Refrigerants
Tomorrow
Syste
ms ≤
40kW
S
yste
ms >
40kW
Cascade Booster
R744 R744
R450A, R513A
R448A/R449A/R134a HFO GWP <150
Centralized DX LT
HFO GWP <150
HFO
R290
Today
Centralized DX
Flammable
Mildly flammable
Non flammable
MT w/ secondary
GWP < 1500
5 5
Hermetically Sealed
R290
HFO GWP <150
Today
Centralized DX
R404A
R407A/F
HFO? R290
R450A,R513A
R448A/R449A/R134a
Indirect Systems
R450A, R513A,
R448A, R449A, R134a, R407A/F
Non Hermetically Sealed
ENTR Lot. 1
For condensing
Units
Commercial Refrigeration System Architecture & Refrigerants
Tomorrow
Syste
ms <
40kW
S
yste
ms >
40kW
Cascade Booster
R744 R744
R450A, R513A
R448A/R449A/R134a HFO GWP <150 ?
Centralized DX LT
HFO GWP <150?
R290
Small charge
R290
Medium & large charge
R290 medium charge
Trend
MT w/ secondary
GWP < 1500
Flammable
Mildly flammable
Non flammable
6 6
Residential Heating Architecture & Refrigerants Trend
R1234 Blends &
R32 Low Temp.
Ou
tdo
or
Mo
no
blo
c.
R410A / R407C Architecture
Future
Ind
oo
r
(B/W
) In
-
Ou
tdo
or
R290
Today
• ≤ to 8kg* or
• ≤ 40kg* w/ vent’d
Enclosure
• ≤ 1kg or
• ≤ 5kg w/ vent’d
Enclosure
• > 5kg National Std.
• ≤ 5kg
• > 5kg National Std.
• ≤ 40kg
Challenges Availability DHW (R32) Safety
Up to 10 kW
(*) Regulatory Standard under revision to increase A2L charge
Up to 50 kW
Up to 50 kW
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Heating Performance w/ Load Variation Degradation Factor impacting the COP
Cycling (Cd)
CD (Degradation Coefficient): The measure of the efficiency loss due to the cycling of the unit. Smaller Is Better!
COPPL = COPd × (1−Cd ×(1−CR ))
COPPL: According to EN14825
8 8
R290 Compressors Trend
Fixed Speed
HFC Scroll
Fixed Speed
R290 Scroll
Variable Speed
R290 Scroll
Compactness
Weight
Natural Refrigerant
Energy Efficiency
Single Compressor To Cover
Multitude System Range
R290 VSS Applications: Self-Contained Cases, Ref Small Chiller And Monobloc HP
9 9
R290 Scroll Compressor Line-Up Heating Application
0
10
20
30
40
50
60
70
80
-40 -30 -20 -10 0 10 20 30
R290 R410A EVI R410A Non EVI
– Compressor with DC Brushless Motor
– Frequency Drive (220VAC Single Phase)
– Motor Speed from 15 to 120 Hz
– Requires special design consideration
– Inverter generates electro-magnetic interference (EMI)
– Variable shaft speed necessitates piping circuits to ensure Oil return
– Variable speed requires special consideration to avoid resonances
10 10
1
1.4
1.8
2.2
2.6
3
0 2000 4000 6000 8000
CO
P
Compressor Speed (rpm)
50 C
35 C
-10 C evaporating
R290 Scroll Performance & Map Refrigeration Application
–COP quasi costant at full range of speeds
ZBV021
–Wide operating Envelope with R290
–(2400 to 4800 rpm full operating limit)
11 11
Relevant Regulations & Standards Charge Limits for R290
EN 378 (Refrigeration Systems)
System Design
&
System
Location
Occupancy
Public
Access
Supervised
Occupancy
Authorized
Access Only
All in Occupied
Space 1.5 2.5 10
Compressor &
Receiver in
unoccupied
space
1.5 2.5 25
All in Open
Space or
Machinery
room
5 10 unlimited
- 40 (Household and Similar Electrical Appliances)
Max. Charge 5 kg
- 89 (Commercial Ref. Appliances): Max. charge 150g with no restriction
Sm
all
Sys
tem
L
arg
e S
ys
tem
Refrigeration Comfort
Occupancy
Public
Access
Supervised
Occupancy
Authorized
Access Only
1.0 1.0 1.0
1.0 1.0 1.0
5 10 unlimited
And Charge is Limited by Room Volume
IEC 60335-2
Charge limit in kg
12 12
• Risk Assessment
0
10
20
30
40
50
60
-5 5 15 25 35 45 55 65 75
Vis
co
sit
y (
cS
t)
Temperature ( C)
Oil Viscosity
R404A 3MAF R290 3MAF R290 HXL 4467
Tevap. -10°C
Dedicated Scroll Compressor Design
• Design review driven by PED req’t – Shell, fittings
– New Material and Processes
• Reliability Refrigerant highly solubile in lubricant.
Newly Developed lubricant for viscosity
improvement
– Electrical components source of ignition and Hot
surfaces exceeding auto-ignition temperature,
Shall not be located in an area where a potentially
flammable mixture of refrigerant and air could
accumulate. (IEC60079, IEC60335-2-40)
13 13
Conclusions • F-gas Regulation pushing towards the lowest GWP
refrigerant
• Modulation with VS provides significant energy savings
• Propane (R290) Compressor with Variable DC motor gives High Efficiency over a wide range of speed
• R290 supports more extreme working conditions
• Propane (R290) should be a future proof refrigerant for dedicated Refrigeration and HP systems
• Propane R290 needs Dedicated compressor design because of safety and reliability
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