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Ammonia Refrigeration & Scenario in Industrial Refrigeration
By
Ramesh Paranjpey
ASHRAE Fellow Life member
5th March 2014
Basic Components Of A Refrigeration
System
Refrigerant Flow Path
Refrigerant ?
REFRIGERANT EVALUATION PROCESS
1. ENVIRONMENT
2. PERFORMANCE
3. ENERGY EFFICIENCY
4. TOXICITY/SAFETY
5. FLAMMABILITY
6. MATERIAL CPMPATIBILITY
7. STABILITY
8. COST
THERMAL/PHYSICAL PROPERTIES
•BOILING POINT
•DISCHARGE TEMPERATURE
•DISCHARGE PRESSURE
•SPECIFIC VOLUME
•DENSITY
•LATENT HEAT OF VAPORISATION
•COMPRESSOR DISPLACEMENT
•HORSE POWER PER TON
•COP
Ammonia Refrigeration & Scenario in Industrial Refrigeration
Why Ammonia ?
5th March 2014
Reasons for Selecting Ammonia Refrigerant
• ODP-0
• GWP < 1
• Atmospheric Life- 0.01 years
• Natural Refrigerant
• Highest Efficiency-Better Heat Transfer
Properties
• Easier Oil Management
• Low Cost-Easy Availability
Natural Refrigerants
(Zero ODP & Ultra-low GWP Refrigerants)
• Hydrocarbons (HC-290, HC-600a)
• Ammonia (R-717)
• Carbon Dioxide (R-744)
• Water (R-718)
• Air
Refrigerants Time-line
1875 1900 1925 1950 1975 20001850
SO2NH3
CFCs
CH3Cl
HCFCs
HFCs
HCs
air
water
CO2
© A Pearson 1999
PHYSICAL PROPERTIES
TOXICITY HOW MUCH
HOW LONG
FLAMABILITY
EXPLOSIVENESS
ODOUR PUNGENT
DETECTABLE-5PPM ONWARDS
LEAKAGE TENDENCY LESS LOSS-PURGING/LEAKS
8.2CFT/LB AGAINST1.2CFT/LB
FOR R-22
MOISTURE TOLERENCE IMMENSE-AQUA/AMMONIA
OIL MISCIBILITY IMMISCIBLE
ASHRAE Standard 34.1-2013-Toxicity/Flammability
Flammability in Air @ 60°C & 101.3 kPa ASHRAE Standard Safety Group
Higher Flammability
LFL or ETFL60 ≤ 100 g/m3 OR HOC ≥ 19 MJ/kg
A3 B3
Lower Flammability
LFL or ETFL60 > 100 g/m3 & HOC < 19 MJ/kg
A2 B2
Lower Flammability
LFL or ETFL60 > 100 g/m3 & HOC < 19 MJ/kg
with a maximum burning velocity of ≤ 10 cm/s
A2L B2L
No flame Propagation A1 B1
Flammability in Air @ 60°C & 101.3 kPaLower Toxicity
OEL ≥ 400PPM
Higher Toxicity
OEL
< 400 PPM
LFL = Lower Flammability Limit
ETFL60 = Elevated Temperature Flame Limit @ 60°C
HOC = Heat Of Combustion, OEL-Occupational Exposure Limit
Toxicity
5 PPM Onwards Detectable
25 PPMDetected by most – no health hazard exposure
10 – 15 years
100 PPM No dangerous effects, minor irritation.
400 – 700
PPM
Irritation Eyes, Nose, Mucous . Lead to
dryness
1700 PPM Cough, Cramp, Serious Irritation, Injuries
2000 PPM Can Lead to Death
7000 PPM Lethal within few minutes
Comparison of Various RefrigerantsASHRAE Fundamentals 2009 Table 9-29.9
Refrigerant Capacity-
TR
Shaft
Power
HP/ TR
R 717 104.4 245.2 2.349
R-22 104.7 264.9 2.530
R134a 53.8 148.6 2.762
R404A 97.9 290.8 2.970
R 507 102.2 302.3 2.958
R410A 151.5 415.3 2.741
Comparison at -200 F/+95 0F
Ammonia Refrigerant v/s R-22
1. Specific heat of liquid is 4 times - 4 to 1
2. Latent heat of vaporization is- 6 to 1
3. Liquid thermal conductivity is -5.5 to 1
4. Viscosity is less- 0.8 to1
5. Liquid density is less - 0.5 to 1
Field of Applications
1. Ice Plants-commercial/amusement centers
2. Cold storages-Fruit/Vegetables/meat/Fish/Seeds/Dry
fruits
3. Freezing of foods-Fish/meat/Fruits/Vegetables
4. Breweries/ Dairies
5. Chemical/Dyestuff –process cooling
6. Concrete cooling-Dams/Roads/Runways
7. Water Chillers-Air conditioning
8. Thermal storages-Heat Pumps
9. Super markets-Ammonia/CO2 cascade
10.Industrial Process/Fertilizer plants
11.Bottling Plants-Coca Cola/Pepsi
Comparison R404a V/S Ammonia For cold room Design
Basis-3 Rooms, Each 12mx24mx9m-Sotage 500 Ton each
Temperature -200 C, For storage of Frozen Products,
Refrigeration load 3x42kW=126kW
R404a-Air Cooled R717-Ammonia-Water cooled
2units per Room screw compressors-6nos.
Power 22.7 kW each with air cooled
condenser
Two stage reciprocating compressor 4
cylinder, 1 No 54.4 kW power
Evaporator Star Coolers Model 2383, each
2 Fans -999W, with electric defrost each
with 18 kW heaters
Evaporator Star coolers-2383-3fans
0.5kW, gravity flooded, water defrost
Piping, controls, gas insulation etc Evaporative condenser-200 kW heat
rejection, Receiver, piping, gas, controls
,insulation etc.
Total cost without Duty 74,90000 Total cost 4234000+ standby compressor
motor
Total power with out defrost 117.3 kW 68.5 kW
Recent Trends
1. Semi Hermetic Compressors with aluminum
windings
2. High Speed screw compressors-3600 RPM
3. Low Charge systems with high side Float
4. Use of PHE foe condenser/Chiller
5. Air Cooled Ammonia systems with wet pads
6. Direct Expansion systems using miscible oils
7. Ammonia-CO2 Cascade for Super markets
8. Heat pump applications
9. Ammonia blends with DME to reduce toxicity
Pump Circulation overfeed Design systems
ECO Mesh Ammonia Air cooled condenser
http://www.google.co.in/url?sa=i&rct=j&q=&esrc=s&source=images&cd=&cad=rja&docid=RMecJ1Um2ChU7M&tbnid=EOu7dLSoK8g1_M:&ved=0CAUQjRw&url=http://www.starcooler.co.in/air-cooled-condensers-ecomesh-cooling.html&ei=ZfcSU6XGIsSFrQeXtYCIAQ&bvm=bv.62286460,d.bmk&psig=AFQjCNFUp8jaAl6l6ytNWN7cMTnZVSEbJg&ust=1393838285140277
Aluminum Coolers
Modern Packaged Ammonia Systems
•New design (PHEs or spray type shell & tube evaporator)
•Liquid injection system
•Better efficiency (>30%) than HFC134a
•Less charge (0.02 to 0.5 kg/kW) for dry and flooded evaporation
•Higher discharge pressure (up to 40 bar)
•Safety level increased significantly towards “zero leak”
•Used in Europe for both display cabinets and space conditioning
Ammonia for A/C and Commercial Refrigeration
•Ammonia A/C with central plants
•Ammonia display freezer cabinets
•Independent circuits
•Secondary refrigerants used
•Risk free AC&R
PACKAGE CHILLER
AIR COOLED AMMONIA PACKAGE
CHILLER
WATER COOLED PACKAGE CHILLER-SCREW
COMPRESSORS & PHE CONDENSER/COOLER
WATER CHILLER USING RECIPROCATING
COMPRESSOR
& ENCLOSED PHE CONDENSER/COOLER
PACKAGE MILK CHILLER WITH ‘U’ TUBE
ACCUMULATOR
Falling Film Water Chiller
http://www.google.co.in/url?sa=i&rct=j&q=Falling+film+water+chillers&source=images&cd=&cad=rja&docid=R2jZBF8MU0OTIM&tbnid=fCUE72vQO0spUM:&ved=0CAUQjRw&url=http://www.patkol.com/index.php?tpid=0026&ei=3h0fUuLwCsKHrgeXj4HQCQ&bvm=bv.51495398,d.bmk&psig=AFQjCNEoKFh1RVWmwhKK0UqMdFwZhOF6sg&ust=1377857312333300
SPIRAL FREEZER
http://www.google.co.in/url?sa=i&rct=j&q=spiral+freezer&source=images&cd=&cad=rja&docid=k20VEzQ1eNvLkM&tbnid=3iG1UXRjS-dV9M:&ved=0CAUQjRw&url=http://my.packexpo.com/pei2012nn/Public/Booth.aspx?IndexInList=&Upgrade=&FromPage=nzcust_ALExhibitorSearch.aspx&BoothID=119962&Task=ProductsDetails&PRODID=19011&ei=HJFjUe3TGpDs0gXd_oD4BQ&psig=AFQjCNFFAGYaI7SsHACfu3Uk1XvXLWP1Qg&ust=1365565888415475
IQF
http://www.google.co.in/url?sa=i&rct=j&q=iqf&source=images&cd=&cad=rja&docid=ipdi5Lz3Ip53GM&tbnid=jN6qPK8g-FJwkM:&ved=0CAUQjRw&url=http://www.slattumprodukter.no/default.pl?showPage=167&ei=b5JjUcilLdOz0QXIuoCgCg&bvm=bv.44990110,d.ZGU&psig=AFQjCNGaFVogupsorAnYWYQkCqGCWTGa2Q&ust=1365566267360168
IQF
http://www.google.co.in/url?sa=i&rct=j&q=IQF&source=images&cd=&docid=a83SsebnurnkIM&tbnid=C49ULbI7pSdJvM:&ved=0CAUQjRw&url=http://www.ramtechrefrigeration.co.in/iqf-freezer.html&ei=WJNjUeznA4TZ0QXO9oCoBA&bvm=bv.44990110,d.ZGU&psig=AFQjCNF5M68cdVtRK_kpPXDxufSRoNrBZg&ust=1365566593886238
SPIRAL FREEZER
http://www.google.co.in/url?sa=i&rct=j&q=spiral+freezer&source=images&cd=&cad=rja&docid=_1q2uchx_8l_WM&tbnid=zYL6uYbZmiQqxM:&ved=0CAUQjRw&url=http://www.freezer-services.co.uk/freezer-services-news&ei=qJRjUY2TKeeK0AWFu4GQCw&bvm=bv.44990110,d.ZGU&psig=AFQjCNGcxehY57hVcqnDGDBrit1agiaimw&ust=1365566984965314
PLATE FREEZER
http://www.google.co.in/url?sa=i&rct=j&q=Plate+freezer&source=images&cd=&cad=rja&docid=e4DPr9LbYDcHwM&tbnid=mK9ixwOZatKSIM:&ved=0CAUQjRw&url=http://worldbase.xm15.host.35.com/products1.asp&ei=vZVjUcXGG-ec0AXMmoGQBg&bvm=bv.44990110,d.ZGU&psig=AFQjCNHGHb0eI2fEuwMfUNWvGD_xIP9ayw&ust=1365567190025210
CO2 Ammonia Cascade
AMMONIA-CO2 BRINE SYSTEM –FRUIT STORAGE-
HOLLAND
AMMONIA CHILLER AT HEATHROW AIRPORT
AMMONIA-CO2 BRINE SYSTEM –FRUIT STORAGE-
HOLLAND
AMMONIA -CO2 CASCADE
Thank you
Any Questions ?
Ramesh.paranjpey@gmail.com
Cell No.: 9822398220
mailto:Ramesh.paranjpey@gmail.com