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Natural Refrigerant Alternatives
for the Industrial Marketplace
Newark, N.J., August 24, 2016
Andre Patenaude C.E.T. Antonio De LourdesDirector – CO2 Business Development Senior Project Engineer (R&D)
Emerson Climate Technologies Vilter Manufacturing,
Emerson Climate Technologies
Agenda
Why invest in natural refrigerants?
Ammonia applications
Key industrial refrigeration trends
CO2 system architectures
Strategies for warm ambient operation
Summary
Low-GWP Refrigeration?
Step 1, completed:
Thinning of the ozone layer
caused by CFC and HCFC
(banned)
Step 2, ongoing:
global warming damage
caused by HFC
(phased down / usage bans)
CFC = Chlorofluorocarbon
HCFC = Hydrochlorofluorocarbons
HFC = Hydrofluorocarbons
Step 1: Elimination of ozone-depleting refrigerants (CFC and HCFC)
Step 2: Phase-down of global-warming refrigerants (HFC)
Step 3: Ramp-up of CO2 commercial refrigeration equipment
Step 3, ongoing:
natural refrigerants
CO2, propane, ammonia
(ramping up)
2015 Was Warmest Year Since 1880, – USA Today Article, 1/20/16
• COP21 Meeting in Paris, 12/2015
• Nations agreed to limit global
temperature increase to 2 °C
• Countries to update pollution
reduction pledges by 2020
This means reducing
emissions by 40–70%
by 2050 compared
to 2010!
U.S. Environmental Protection Agency (EPA)
• Slide from Tom Land, U.S.EPA, ATMOsphere America, June 17, 2016
Alternatives for Refrigeration Applications
R-410A
like
capacity
R-404A &
R-407/22
like
R-134a
like
GWP level
400-675
< 1500
~600
~300
HFO 1234yf
HFO 1234ze
ARM-42
R410A
R22
R407A
R407C
R407F, R452A = XP44
ARM-35
0 500 1,000 1,500 2,000
Pressure
or
R32/HFC/HFO
Blends
R-32/HFO
Blends
HFC/HFO
BlendsR134a
CO2
R404A
R507A
DR2, N12, ARC 1
R290
NH3
A1 – Non-flammable
A2L – Mildly flammable
A3 – Flammable
B2L – Toxic, mildly flam.
R-123 like
(v. low pr.)
(3922)
R-32
R32/HFO Blends
R448A
R449A
R449B
R450A = N13
R513A = XP10
R-444B = L20
L40, DR7
ARM-20b
R-455A (HDR110)
DR3
ARM-20a
R-446A, R-447A, ARM-71a
<150
Qualitative; not to scale
R-515A
HFC and/or natural booster / high stage
(no CO2)
System Architecture Landscape
High stage
HFC or natural
(no CO2)CO2
BoosterVolatile brine
CO2-NH3 (or HFC) cascade system
CO2 booster transcritical
CO2 subcritical system CO2 transcritical systemSingle stage
Holistic Facility Approach Can Minimize
“Unintended Consequences”
Equipment
Energy
Economics
Environment
Toxicity, flammability,
working pressures
Heat transfer,
latent heat
Revenue, first cost,
total cost of ownership
CO2 emissions, climate
change
Legal, operations
Energy mgr.,
design eng.
CEO, merchandising, finance
Sustainability officers
Lack of technicians,
performance specs and
service contracts
Utility incentives,
continuous
commissioning,
integrated HVACR
Millennials,
fresh, urban stores
Natural refrigerants,
regulations
Key variables Stakeholders Trends
Refrigerants: Impact Comparison
Refrigerant R-404A R-507A R-22R-290
Propane
R-744
CO2
R-717
Ammonia
Ozone depletion
potential(ODP) 0 0 0.04 0 0 0
Global warming
potential (GWP)
3,700 3,800 1,810 3 1 0
Safety group A1 A1 A1 A3 A1 B2
Reference: ASHRAE Handbook
Ammonia Applications
• Food and beverage processing:
– Dairy, meat processing, breweries, baked goods, frozen foods
• Refrigerated cold storage
• Recreational ice:
– Hockey rinks, curling, ice skating paths
– Olympic speed skating, ski jump, bobsled tracks
• Ground soil freezing, mining HVAC
• HVAC, district heating and cooling, heat pumps
Ammonia Pros
Cost-effective
• Ammonia systems cost ~10–20% less than competitive systems using HCFCs and HFCs
• Less refrigerant required, smaller pipes required due to less mass flow: over nine times more energycontent (Btu/lb) than HFCs
• Up to 25% more efficient in energy usage
• Excellent refrigerant for heat recovery
• Low-cost refrigerant and oils:– Mineral and semi-synthetic oils
• Low-cost refrigerant and oils:– Mineral and semi-synthetic oils
Reference: ASHRAE Handbook
Ammonia: A Natural Refrigerant
Natural refrigerant, environmentally friendly:• One of the most abundant gases in the environment
• Exists all around us (air, water, soil, produced by our kidneys)
• Approx 1.7 times lighter than air
• Breaks down rapidly in the environment
• NH3 (R-717): Nitrogen and hydrogen
• Ozone-depletion potential (ODP) = 0
• Global warming potential (GWP) = 0 N
H
H
HReference: ASHRAE
Handbook
Reference: ASHRAE Handbook
Human production: 198 million tons annually (2012)
• Second-most produced chemical (after petroleum)
• ~80% is produced for fertilizer
• NH3 R-717 refrigerant 99.98% pure ~ 2% of
total production
• Cheap, affordable refrigerant
150 Years of Ammonia Refrigeration
Well known:
• Ammonia used for more than 150 years in refrigeration
• 1850s in France, 1860s in U.S., first patents in 1870s
• Consistently used for large industrial refrigeration for over 100 years
• Most common refrigerant for food and beverage production, cold storage, recreational refrigeration
• Proven safe track record
Key Industrial Refrigeration Trends
• Safety and environmental requirements
– OSHA requirements
– Low-charge ammonia systems
– Moving ammonia out of occupied spaces
– Cascade systems using CO2 in the low stage
– Booster transcritical CO2 architecture for MT and LT
– Increased use of R-744 (CO2) and a volatile secondary fluid
• Increased emphasis on total cost of ownership
– Equipment cost
– Maintenance costs
– Energy cost (improved performance of CO2 at LT such as -40 °F)
Key Industrial Refrigeration Trends
• Safety and environmental requirements
– OSHA requirements, 10,000-lb threshold
The burden of compliance will continue to be significant, with
OSHA’s National Emphasis Program (NEP) inspections, audits
and regulation changes related to the OSHA 1910.119 PSM
program and the U.S. Environmental Protection Agency’s (EPA)
40 CFR Part 68 Risk Management Plan.
PSM programs (process safety and risk management)
Key Industrial Refrigeration Trends
• Safety and environmental requirements
– OSHA requirements
– Low-charge ammonia systems
Key Industrial Refrigeration Trends
• Safety and environmental requirements
– OSHA requirements
– Low-charge ammonia systems
– Moving ammonia out of occupied spaces
Key Industrial Refrigeration Trends
• Safety and environmental requirements
– OSHA requirements
– Low-charge ammonia systems
– Moving ammonia out of occupied spaces
– Cascade systems using CO2 in the low stage
Key Industrial Refrigeration Trends
• Safety and environmental requirements
– OSHA requirements
– Low-charge ammonia systems
– Moving ammonia out of occupied spaces
– Cascade systems using CO2 in the low stage
– Increased use of R-744 (CO2) and a volatile secondary fluid
Contained in
equip room
Med-temp
Low-temp
Ammonia Evolution: The Future
Ammonia technology trends:
• Lower-charge systems, critically charged systems
– DX ammonia increasingly possible thanks to electronic controls, valves
• Combined ammonia / CO2 cascade
• Ammonia / pumped glycol secondary
• Ammonia / pumped CO2 secondary
• Consistent development of ammonia compressors and equipment …
• Removes ammonia from occupied space
Med-temp
Low-temp
CO2 System Architectures — Booster vs. Cascade vs. Secondary
CO2 DX
CO2 DX
CO2 DX
Transcritical
boosterCascadeSecondary
CO2 Secondary System — Schematic
The CO2 would typically be cooled to
-20 °F (200 psig) for the LT load
+20 °F (407 psig) for the MT load
The high-stage system is a simple chiller type system,
typically running on an HFC or HC or ammonia.
-40 °F
+20 °F
CO2 pumped as
volatile brine
CO2 direct
expansion
Metro Distribution Centre, Laval, QC: Ammonia / Secondary CO2 System
Facility• 240,000 square foot cold storage warehouse
• 1000 TR ammonia refrigeration with efficient Emerson / Vilter
single-screw compressors
• Distributed CO2 brine throughout the building
Emerson solution• Vilter compressors delivered superior part-load efficiency
• Expensive VFD drives would have been required with competitor’s
twin-screw compressors
End user benefits• Reduced ammonia charge
• Lower compressor and facility energy costs
• Non-ozone depleting refrigerants with zero global warming potential
• Vilter dual-slide valve technology avoids more than $100,000 of
compressor VFD drives
R-744 vs. HCFC/HFC
R-744 HFC / HCFC Impact on R-744 Systems
Global warming potential
Ozone-depleting potential
1
0
1,300 to 4,000
0 for HFC / high for HCFC
Future proof
Future proof
Saturation pressures
Operating pressures
Standstill pressures
(Power outages)
Higher
Higher
Higher
Rapid pressure rise
Lower
Lower
Lower
Lower
Additional safety design
Specialized components
Relief valves/tanks, etc.
Pressure relief venting
Inert gas
Flammability
Toxicity
Odor
Yes
A1
No
None
Yes
A1
No
None
Copper may be used
Not flammable
Asphyxiate in high concentrations
Leak detection required
Volumetric mass flow
Heat transfer
High ambient performance
Low ambient performance
Higher
Higher
Lower
Good
Lower
Lower
Higher
Good
Smaller tubes and compressors
Better thermal efficiency
System design to compensate
Subcritical cascade favorable
Cost per pound
Complexity of systems
Adoption
Legislation / regulations
Low
Higher
Low
Low
Higher
Lower
Higher
Higher
Economical
Higher first cost, training and experience
Higher first cost
Long-term viability
R-744 Provides Many Benefits Over HFC Options.
Pressure-Enthalpy Diagram, CO2
Liquid and gas density
are the same ONLY at
critical point.
https://www.youtube.com/watch?v=-gCTKteN5Y4
CO2 DX
CO2 DX
CO2 DX
Transcritical
boosterCascadeSecondary
Selecting the Best System — Booster vs. Cascade vs. Secondary
Introduction to Cascade — Simple Systems
Simple cascade system comprises:
• Low stage provides the cooling load
It uses CO2 and is always subcritical
• High stage absorbs heat from the
condensing CO2 at the cascade HX
• CO2 condensing temperature is always
below the critical point
• High stage is usually a simple, close-
coupled system
• Typically applied in warm climates
High stage
(HFC or ammonia)
Low stage
CO2
NH3/CO2 Cascade
• Move NH3 out of
occupied space
• Improved efficiency
• Regulatory
compliance
• Natural refrigerant
Primary
stage
NH3
MT
LT
Low-temp
DX — CO2
25 °F = 440 psig
-30 °F = 163 psig
New CO2 Subcritical Open Drive
• Vilter – division of Emerson Climate Technologies
• Founded in 1867 in Wisconsin
• Currently in Cudahy, Wis.
• Products include:
– Recips, single screws, packaged systems for:
• Refrigeration, heat pumps
• Smart vapor management, gas compression for CHP
550 SeriesSingle screwPackage systems SVM unit
552 Test Site: The Helix, Innovation Center
Dayton, Ohio (Startup Sept. 15)
Combined circuit on a common
skid with two cylinder compressors
working in parallel to provide
50 tons at -35 °F SST 25 °F SCT
Ability to test at “real” conditions
Development of the HP Reciprocating Compressor
Vilter 552 Vilter 554 Vilter 556 Vilter 558
1,800 RPM 1,800 RPM 1,800 RPM 1,800 RPM
CFM 56 112 168 224
-30 °F SST/23 °F
SDT
Capacity
(tons)48 97 145 193
BHP 56 112 167 223
-58 °F SST/23 °F
SDT
Capacity
(tons)23 46 69 92
BHP 48 96 145 193
Production statusTesting stage
(Helix)Design stage Design stage
Prototype
stage
CO2 DX CO2 DX
CO2 DX
Transcritical
boosterCascadeSecondary
Selecting the Best System — Booster vs. Cascade vs. Secondary
Time Spent in Transcritical
1,020 hrs/yr
w/std. gas cooler
9 hrs/yr
w/adiabatic
gas cooler
202 hrs/yr
w/std. gas cooler
Toronto, ONAtlanta, GA
Five Ways of Improving Efficiencies in Warm Ambient Regions
• Spray nozzles
• Evaporative or adiabatic gas coolers
• Parallel compression
• Sub-cooling
• Ejectors
Supermarket LCCP Analysis
Annual Energy LCCP LT = Low-temperature
MT = Medium-temperature
DX = Direct expansion
LCCP = Life cycle climate performance
Min Cond: 70F
Min Cond: 70F
Min Cond: 70F
Min Cond: 50F
Assumptions
LT load: 384 MBTU
MT load: 1,250 MBU
Leak rate assumptions: 15% for all systems
Note: 15% is probably high for the ammonia systems. Even if we use 0% it will not change the results, as the GWP for ammonia is 0.
Electric generation factor: 1.5 lbs CO2/kWh
Ammonia system was assumed to be single-stage with no subcooling.
Summary of Options
-40 °F
+20 °F
CO2 pumped as
volatile brine
Medium-temp CO2 direct
expansion
Low-temp
CO2 pumped as
volatile brine
Low-temp only
CO2 pumped as
volatile brine
Medium-temp only
Ammonia
Compressor
Ammonia
Compressor
100% ammonia system
Ammonia/CO2 cascade with MT pumped secondary
CO2 transcritical booster system
Questions?
DISCLAIMER
Although all statements and information contained herein are believed to be accurate and reliable, they are presented without guarantee or warranty of any kind, expressed or
implied. Information provided herein does not relieve the user from the responsibility of carrying out its own tests and experiments, and the user assumes all risks and liability for
use of the information and results obtained. Statements or suggestions concerning the use of materials and processes are made without representation or warranty that any such
use is free of patent infringement and are not recommendations to infringe on any patents. The user should not assume that all toxicity data and safety measures are indicated
herein or that other measures may not be required.
Thank You!
Andre.Patenaude@Emerson.com
519-717-5282
Antonio.Delourdes@Emerson.com
414-486-2634
For further details, contact
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