Vilter single screw heat pump

The World’s Best Compressors
For Industrial Refrigeration
TM
Single Screw
Ammonia
Heat Pumps
Harness Your Heat...
Don’t Reject It
Vilter Single Screw Ammonia Heat Pumps
•
•
•
•
Convert Waste Heat to Hot Water, Up to 195° F (90° C)
Reduce or Eliminate Hot Water Boilers
Retrofit Existing Ammonia Refrigeration Systems
High Coefficient of Performance (COP) at Full or Part Load
Conventional Food and Beverage Processing Plants
Utilize Two Opposing Paths of Energy
Refrigeration
Heat Energy OUT
Refrigeration systems
absorb heat but then
reject it back into the
atmosphere.
Fossil Fuel
Heat Energy IN
Simultaneously, plant demands
for hot water, such as process
room clean-up activities, use
fossil fuel energy to heat water.
Vilter Single Screw Ammonia Heat Pumps Harness the Heat from
Refrigeration and Bridge the Gap for the Beneficial Use of Rejected Heat
High pressure Vilter Heat Pump Compressors allow plants to conserve energy by transferring
refrigeration waste heat into useful hot water heating, while reducing or eliminating hot water boilers
and the fossil fuels they consume.
Single Screw Ammonia Heat Pump
Single Stage Scavenging Heat Pump System
Desuperheating
Oil Cooling
Subcooling
Condensing
Ammonia Refrigeration Systems
Available Waste Heat
Oil Cooling
& Desuperheating
High Temperature Ammonia
Pressure and Temperature
Single Screw Ammonia Heat Pump
°F
psia
psig
cuft/lb
°C
barA
90.0
95.0
100.0
105.0
110.0
115.0
120.0
125.0
130.0
135.0
140.0
145.0
150.0
155.0
160.0
165.0
170.0
175.0
180.0
185.0
190.0
195.0
200.0
205.0
180.76
195.91
212.01
229.09
247.19
266.34
286.60
307.98
330.54
354.32
379.36
405.70
433.38
462.45
492.95
524.94
558.45
593.53
630.24
668.63
708.74
750.64
794.38
840.03
166.06
181.21
197.31
214.39
232.49
251.64
271.90
293.28
315.84
339.62
364.66
391.00
418.68
447.75
478.25
510.24
543.75
578.83
615.54
653.93
694.04
735.94
779.68
825.33
1.6588
1.5319
1.4163
1.3108
1.2144
1.1262
1.0452
0.9710
0.9026
0.8397
0.7817
0.7280
0.6785
0.6325
0.5899
0.5504
0.5136
0.4793
0.4473
0.4174
0.3895
0.3633
0.3387
0.3156
32.2
35.0
37.8
40.6
43.3
46.1
48.9
51.7
54.4
57.2
60.0
62.8
65.6
68.3
71.1
73.9
76.7
79.4
82.2
85.0
87.8
90.6
93.3
96.1
12.46
13.51
14.62
15.80
17.04
18.36
19.76
21.23
22.79
24.43
26.16
27.97
29.88
31.88
33.99
36.19
38.50
40.92
43.45
46.10
48.87
51.75
54.77
57.92
Single Stage Scavenging Heat Pump System
Ammonia Heat Pump Scavenging System
Scavenger Oil Cooling
& Desuperheating
Subcooling
Condensing
Host Oil Cooling
& Desuperheating
Existing Refrigeration System
Single Stage Heat Pump Scavenging System
Single Screw Ammonia Heat Pump
A scavenging heat pump system is designed to pull heat out of an existing refrigeration system by
diverting ammonia discharge gas away from refrigeration system condensers to the suction inlet
of the heat pump system. Vilter single screw compressors are designed to handle the high suction
pressures required of this duty, and deliver the very high discharge temperature vapors for water
heating in order to make use of the refrigeration system’s waste heat. In heating water to moderate
temperatures, up to 160° F (71° C), single stage single screw heat pump systems provide optimal
performance (COP’s) due to the duty’s relatively low differential pressures, up to 350 psid.
Single Stage Ammonia Heat Pumps
Heat Water from 55°F to 155° F
Compressor
Model
°F (°C)
Nominal
Water
Flow
GPM (m3/hr)
160 (71)
Suction
Pressure
SST
Discharge
Pressure
SDT
psig (barg)
°F (°C)
psig (barg)
mBTUH (kW)
Total
Absorbed
Power
HP (kW)
unitless
72 (16.4)
4874 (1429)
305 (228)
6.28
Heat
Recovered
COP
VSS-291
178 (12.1) 94 (34.5) 478 (32.5)
VSS-341
178 (12.1) 94 (34.5) 474 (32.2) 159 (70.5)
84 (19.1)
5657 (1658)
354 (264)
6.28
VSS-451
178 (12.1) 94 (34.5) 468 (31.9)
158 (70)
126 (28.6)
8540 (2503)
517 (386)
6.49
VSS-601
178 (12.1) 94 (34.5) 469 (31.9)
158 (70)
149 (33.9)
10041 (2943)
599 (447)
6.59
* Based upon compressors operating at 3550 RPM (60 Hz)
Single Stage Ammonia Scavenging Heat Pump Package
Single Screw Ammonia Heat Pump
Two-Stage Scavenging Heat Pump System
Ammonia Heat Pump Scavenging System
2nd Stage Oil Cooling
& Desuperheating
Subcooling
Condensing
1st Stage Oil Cooling
& Desuperheating
Host Oil Cooling
& Desuperheating
EXISTING AMMONIA REFRIGERATION SYSTEM
Existing Refrigeration System
TWO-STAGE HEAT PUMP SCAVENGING SYSTEM
Two-Stage Heat Pump Scavenging System
LOW STAGE
DESUPERHEATER
SYSTEM
CONDENSOR
MAIN
DISCHARGE GAS
1ST STAGE
COMPRESSOR
2ND STAGE
COMPRESSOR
OIL COOLER
OIL COOLER
INTERCOOLER
HIGH STAGE
DESUPERHEATER
EXISTING
COMPRESSORS
OUTLET WATER
EQUALIZING
MAIN SYSTEM
LIQUID
MAIN RECEIVER
LEVEL CONTROLLER
CONDENSER
SUBCOOLER
INLET WATER
Single Screw Ammonia Heat Pump
Two-stage scavenging heat pump systems are utilized where the desired water temperatures are higher than
those provided by single stage systems. Higher differential water temperatures correlate to higher differential
pressures in heat pump compressors. By splitting the heat pump design from a single stage to a two-stage
system, superior COP’s are realized in achieving very high water temperatures, up to 195° F (90° C). Vilter
single screw compressors employed to satisfy the high pressures and temperatures of two-stage ammonia
heat pumps operate reliably and efficiently at such intensive duties due to their naturally balanced axial and
radial design.
Two-Stage Ammonia Heat Pumps
Heat Water from 55°F to 190° F
Stage
Compressor
Model
Suction
Pressure
SST
Discharge
Pressure
SDT
Power
psig (barg)
°F (°C)
psig (barg)
°F (°C)
HP (kW)
Nominal
Water
Flow
GPM (m3/hr)
mBTUH (kW)
Total
Absorbed
Power
HP (kW)
unitless
Heat
Recovered
COP
Low
High
VSS-451
VSS-291
178 (12.1) 94 (34.5) 371 (25.2) 141 (60.5)
366 (24.9) 140 (60) 721 (49.0) 193 (89.5)
383 (286)
425 (317)
130 (29.5)
8772 (2571)
808 (603)
4.27
Low
High
VSS-601
VSS-341
178 (12.1) 94 (34.5) 370 (25.2) 141 (60.5)
365(24.8) 140 (60) 720 (49.0) 193 (89.5)
445 (332)
498 (371)
158 (35.9)
10680 (3130)
942 (703)
4.45
Low
High
VSS-901
VSS-451
178 (12.1) 94 (34.5) 371 (25.2) 141 (60.5)
366 (24.9) 140 (60) 721 (49.0) 193 (89.5)
766 (571)
768 (573)
234 (53.2)
15819 (4636)
1534 (1144)
4.06
Low
High
VSS-1051
VSS-601
178 (12.1) 94 (34.5) 370 (25.2) 141 (60.5)
365 (24.8) 140 (60) 720 (49.0) 193 (89.5)
828 (618)
867 (647)
271 (61.6)
18339 (5375)
1694 (1264)
4.25
* Based upon compressors operating at 3550 RPM (60 Hz)
Two-Stage Ammonia Scavenging Heat Pump Package
Single Screw Ammonia Heat Pump
Stand-Alone Heat Pump System
The city of Drammen, Norway is embarking on
a novel energy saving plan using an ammoniabased stand-alone heat pump system. When
the project comes on line, all of Drammen’s
hot water heating needs with be supplied
with energy extracted from the frigid North
Sea, greatly reducing the use and emissions of
fossil fuels.
The city of Drammen (population 60,000) needed
hot water at 90° C (194° F) for their new district
heating system. Using ammonia refrigerant (R-717)
the project is highly efficient, greatly reduces the
use of fossil fuels, and has no negative impact on
the ozone layer or global warming.
The use of heat pumps to
extract heat from air and water
is increasingly popular, largely
because the heat they deliver
far exceeds the energy they
consume.
Vilter engineers, collaborating
with Star Refrigeration and
Norsk-Kulde, made use of Vilter
single screw compressors to
produce the pressures and
temperatures required for the
system.
IT’S NEVER
BEEN DONE
BEFORE
Courtesy of Star Refrigeration
Emerson.com/StarRefrigeration
Vilter reserves the right to make changes in design and specifications without notice.
Emerson and Vilter are trademarks of Emerson Electric Co. or one of its affiliated companies.
©2010 Emerson Electric Co. All rights reserved. Printed in the USA
v11 3/2010