Low Charge ADX Ammonia. Presented by: Bruce Nelson, President, Colmac Coil Manufacturing Rick Watters, Vice President, AMS Mechanical Systems

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2 Low Charge ADX Ammonia Presented by: Bruce Nelson, President, Colmac Coil Manufacturing Rick Watters, Vice President, AMS Mechanical Systems

3 Background Why use ammonia? It s a natural refrigerant ODP = zero, GWP < 1 Abundant and low cost Widely used for over 100 years It is energy efficient! Table 8 Comparative Refrigerant Performance (Te = -25F, Tc = 86F) Refrigerant R744 Net Refrigerating Effect, Btu/lb 56.8 Refrigerant Circulated, lb/min 3.52 Power Consumption, Hp Coefficient of Performance R507A R404A R R

4 Background Concerns with ammonia: Toxicity Flammability Regulations (> 10,000 lbs) OSHA Process Safety Management (PSM) EPA Risk Management Program (RMP) DHS Chemical Facility Anti-Terrorism Standards (CFATS)

5 Background Regulation and risk has driven interest in new low charge ammonia technologies Advanced Direct Expansion (ADX) is one method of reducing ammonia charge

6 Low Charge ADX Ammonia Benefits: Much smaller ammonia charge 7 lbs/tr vs 30+ lbs/tr for pumped bottom feed 30X to 50X charge reduction in evaporators Ammonia charge <10,000 lbs even for large systems Energy Efficient Lower first cost compared to pumped ammonia

7 Making ADX Ammonia work Three critical issues must be addressed: 1. Separated flow in evaporator tubes - Tube ID enhancement 2. Management/removal of water - Only dry high pressure liquid is used - Trap and remove water at the accumulator 3. Refrigerant distribution - Tank Distributor technology

8 Low Charge ADX Ammonia Many systems now in operation USA, Canada, Australia Large cold storage distribution centers Food service distribution centers Food processing facilities

9 Low Charge ADX Case Studies Rick Watters, AMS Mechanical Systems Vice President of Refrigeration/Food Process Piping

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12 WHY USE ADX AMMONIA? Lower refrigerant operating charge Simplify Operation Location Location Location

13 JCS aerial view

14 JCS plan view with Phase 2-10 F/ +40 F CONVERTIBLE ROOM -10 F/ +40 F CONVERTIBLE ROOM -10 F FREEZER -10 F/ +40 F CONVERTIBLE ROOM -10 F FREEZER -10 F/ +40 F CONVERTIBLE ROOM -10 F FREEZER +40 F DOCK +40 F DOCK OFFICE SUPPORT MECH ROOM

15 LCS aerial view

16 +40 F COOLER LCS plan view with Phase 2 PRODUCTION +40 F COOLER -10 F/ +40 F CONVERTIBLE ROOM -10 F FREEZER -10 F FREEZER +40 F COOLER +40 F DOCK +40 F DOCK OFFICE SUPPORT MECH ROOM +40 F PRODUCTION MECH ROOM SUPPORT

17 JCS Refrigeration System Highlights Single stage economized -15/+20/+95 Thermosyphon oil cooling Anhydrator System Cleaner H.A. Phillips transfer system Controlled pressure receiver +20 and -15 accumulators Nickel-Brazed Liquid Sub-Cooler Motorized TXV s

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19 Liberty Cold Refrigeration System Highlights Single stage economized -15/+20/+95 Thermosyphon oil cooling H.A. Phillips transfer systems Controlled pressure receiver +20 and -15 accumulators Nickel-Brazed Liquid Sub-Cooler Pulse Width TXV s

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21 Refrigeration System Highlights VFD s on large evaporator fans

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23 Refrigeration System Highlights VFD s on large evaporator fans ADX Evaporators

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27 Refrigeration System Highlights VFD s on large evaporator fans ADX Evaporators Low Charge Condenser

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31 Refrigeration System Highlights VFD s on large evaporator fans ADX Evaporators Low Charge Condenser Low Charge Vessels

32 JCS vessels

33 LCS vessels

34 JCS engine room

35 LCS engine room

36 Operating Efficiency Calculated 1.3% more Hp per ton compared to Liquid Overfeed Systems as worst case

37 Refrigerant Charge Comparison JCS with Phase 2 Liberty Comparison Freezer Temp. Deg. F Freezer sq. ft. 300, ,600 90,301 Convertible room. Deg. F -10/35-10/28-10/35 Convertible room sq. ft. 37,800 15,700 45,311 Dock Temp. Deg. F Dock/Cooler area sq. ft. 63,600 88,500 35,958 Central Refrigeration System ADX ADX Pumped Liquid Refrigeration tons 1, Ammonia charge lb. 8, ,000 Total refrigerated sq. ft. 401, , ,610 Charge per square foot.0212 #/sqft.0298 #/sqft #/sqft Charge per Ton of Refrigeration 8.02#/TR #/TR #/TR

38 Electrical Comparison Comparison JCS Phase 1 only Liberty Phase 1 only Refrigerated space sq. ft. 137,448 ft² 201,805 ft² 135,807 ft² Central Refrigeration Control System No Yes Yes VFD s on Large Evaporator Fan Motors No VFD s VFD s VFD s Motion Sensing LED Lighting No Yes Yes Blast Freezing No Yes Yes 2015 Total Power Usage (KWH) 5,165,708 KWH 4,721,655 KWH 4,227,007 KWH Annual Average Power per sq. ft KWH/ ft² 23.4 KWH/ ft² 31.1 KWH/ ft² Percent Difference (%) 0% 38% 18%

39 Construction Cost 2.37% savings over a liquid over feed $100,000.00

40 Design Considerations Use the recommended oil (Frick #9 in this case) Keep the system dry and oil free You will have some liquid return. Defrost, under floor system. Be able to deal with it Going to a fluid cooler for compressor oil cooling in place of thermosyphon would have reduced the ammonia charge 750#

41 Design Considerations (cont.) Fluid cooler system would have added $300, of install cost to the project Liquid injection would lower the install cost and refrigerant charge but would have decreased operating efficiency's by and additional 4.5% Law of unintended consequences

42 In Summary ADX Evaporators worked as advertised System is easy to work on Restarts quickly after power failure Both Motorized and Pulse Width DX valves work great Add Hot Gas heat cycle to evaporators in Coolers/Dock depending on location 5 projects completed, 1 under construction

43 Questions?