Post on 20-Dec-2015
Alexander Pavlov
IETC, New Orleans, 20-21/05/10
Energy Efficiency in Compressed Air Systems
2
Atlas Copco in a Snapshot
A world-leading provider of industrial productivity solutions.
Products and services range from compressed air and gas equipment, generators, construction and mining equipment, industrial tools and assembly systems, to related aftermarket and rental.
In close cooperation with customers and business partners, Atlas Copco delivers sustainable solutions for increased productivity through innovative products and services.
Headquartered in Sweden, the Group’s global reach spans more than170 markets.
In 2009 Atlas Copco had 30 000 employees and annual revenues of approximately BSEK 64 (BEUR 6.0).
3
The Atlas Copco Organization
Executive Group Management and Corporate Functions
Oil-free Air
Industrial Air
Portable Air
Specialty Rental
Gas and Process
Compressor Technique Service
Airtec
CompressorTechnique
Construction and Mining Technique
IndustrialTechnique
Underground RockExcavation
Surface DrillingEquipment
Drilling Solutions
Secoroc
Construction Tools
Road Construction Equipment
Geotechnical Drillingand Exploration
Rocktec
Atlas Copco Tools and Assembly SystemsMotor Vehicle Industry
Atlas Copco Toolsand Assembly Systems General Industry
Chicago Pneumatic
Tooltec
Customer Centers and Service Providers
President and CEO
Board of Directors
4
Worldwide Presence
Production sites
5
Value of Energy in Compressed Air Systems
70% to 80% of life cycle costs is energy
In EU compressed air accounts for 10% of the energy consumed by industry
1 bar lower in pressure, reduces energy by 7%
Typically, after 5 years leakages can take 20% of the total air consumption
Some useful facts and figures
Investment 12%
Installation 3%
Maintenance 15%
Energy consumption 70%
Energy Savings
6
CO2 emissions – the big picture
Design of product
Logistics Energy use
Re-use
Design of product
Less electricity consumption
Atlas Copco focus
(95% +)
7
Why Atlas CopcoSaving energy is our way of life
A century of innovation in energy saving features
Over 400 patents
8
EU electricity consumption in compressed air
Real consumption in CAS TWh Share of electricity
In EU the compressed air accounts for 10% of the energy consumed by industry, 80 TWh/year
Source: Compressed air systems in the European Union, 2001, study by Fraunhofer Institute, ADEME, ECE, University of L’Aquila
9
Potential contribution to energy savings
System installation or renewal % applicability(1) % gains(2) Potential contribution(3)
Improvement of drives (high efficiency motors, HEM) 25 % 2 % 0.5 %
Improvement of drives (adjustable speed drives, ASD) 25 % 15 % 3.8 %
Upgrading of compressor 30 % 7 % 2.1 %
Use of sophisticated control systems 20 % 12 % 2.4 %
Recovering waste heat for use in other functions 20 % 20 % 4.0 %
Improving cooling, drying and filtering 10 % 5 % 0.5 %
Overall system design, including multi-pressure systems 50 % 9 % 4.5 %
Reducing frictional pressure losses 50 % 3 % 1.5 %
Optimising certain end use devices 5 % 40 % 2.0 %
System operation and maintenance
Reducing air leaks 80 % 20 % 16.0 %
More frequent filter replacement 40 % 2 % 0.8 %
TOTAL 32.9 %
Table legend: (1) % of CAS where this measure is applicable and cost effective(2) % reduction in annual energy consumption(3) Potential contribution = applicability * reduction
Source: Compressed air systems in the European Union, 2001, study by Fraunhofer Institute, ADEME, ECE, University of L’Aquila
32.9 % = 30.5 TWh/yr = 0.7 million tonnes of CO²/yr
10
Superior solutions
Total energysaving concept
From products to solutionsThe unique approach
Customer needs
coretechnology
drivetechnology
energy saving accessories
energy recovery
demandassessment
optimizationof the room
11
The Energy Circle
Superior solutionsCustomer needs
coretechnology
drivetechnology
energy saving accessories
energy recovery
demandassessment
optimizationof the room
12
Demand assessment
System audit:– Flow measurement
– Pressure measurement
– Power measurement
Report:– Simulation of optimal compressor installation
– Simulation of central control system
– Potential energy savings
Overall system design
13
Leak detection
Ultrasound leak detection
Report– Location
– Leak flow
– Equivalent energy loss
14
System assessmentAirScan - Tools
Hot tapping
Temperature
Leak detection
Flow
Dewpoint measurement
Power/logging device
VIP sens
Measurement box
Flow measurement output
15
The Energy Circle
Superior solutionsCustomer needs
coretechnology
drivetechnology
energy saving accessories
energy recovery
demandassessment
optimizationof the room
16
Oil-free screw compressors55-900 kW
Oil-injected screw compressors5-500 kW
Turbo compressors500-2500 kW
Matching air treatment equipmentDryers,filters,drains,separators,etc
ES – energy saving central controllersOptimization, monitoring, control
Oil-free scroll compressors1-15 kW
Oil-free tooth compressors15-45 kW
Best compression and treatment technologies under one roof
Products
17
Atlas Copco has all the technologies availableS
pec
ific
en
erg
y J/
l (H
p/c
fm)
centrifugalscrewtooth
Power (flow)
scroll
Appropriate selection can save a lot of energy
18 kW 55 kW 750 kW
Energy Savings
18
Before 19902008
Sp
ec
ific
En
erg
y (
J/l
, H
p/c
fm)
1 10 (21.2) 100 (212) 1000 (2,120)
FAD l/s (cfm)
1995 - 20032000 - 2006
System design : innovations in screw elements
3-5%
3%
11kW 22kW 30kW 55kW 90kW 132kW 200kW 300kW
5-6%
19
The Energy Circle
Superior solutionsCustomer needs
coretechnology
drivetechnology
energy saving accessories
energy recovery
demandassessment
optimizationof the room
20
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sunday
l/s
hour
50
100
150
200
250
Typical air demand pattern
Measurement and simulation tools are available to calculate precise energy savings in a real environment
Energy Savings
Average use 50%
21
time
Theory
Loaded pressure
Unloaded system pressure
Energy savings with VSD
T
T- time for complete system venting
Actual
Excess energy
Power consumption during transition from load to no load with traditional regulation
seconds
kW
0
10
20
30
40
50
0
20
40
60
80
10
0
12
0
14
0
16
0
18
0
20
0
22
0
24
0
26
0
Power consumption GA45 L-NL at 50%
Energy savings with VSD
~80%
Power consumption during transition from load to no load with traditional regulation vs. VSD
VSD
23
VSD technology can save up to 35% of energy
centrifugalscrewtooth
Flow m3 / min
scroll
18 Kw 55 Kw 750 Kw
$/M3
Sp
ecif
ic e
ner
gy
J/L
or
$/M
3Energy cost per m3 of air at 7 bar(e) (100 psig)
VSD – Variable speed drives
24
0 250 500 750 1000 kW
Company A
Company B
Company E
Others : mainly promoting free-standing
Company C
Company D
Atlas Copco
Widest integrated VSD range (from 7.5 to 900 KW)
Our commitment to VSD technology
25
The Energy Circle
Superior solutionsCustomer needs
coretechnology
drivetechnology
energy saving accessories
energy recovery
demandassessment
optimizationof the room
26
MD and XD dryers – energy-less air drying
Heat of compression is used for drying
No external energy or purge is required
Very low pressure drops
Energy savings between 5 and 20% are possible !
Efficiency – Air quality
27
Dryer energy consumption (-20oC, -4°F PDP)
Type of dryer
% o
f co
mp
ress
or
po
we
r
7.70%
19.53%
2.30%
0.02%0%
5%
10%
15%
20%
25%
BD heat reactiveted CD purge reactivated XD 0 purge HOC MD HOC
28
The Energy Circle
Superior solutionsCustomer needs
coretechnology
drivetechnology
energy saving accessories
energy recovery
demandassessment
optimizationof the room
29
PRESSURE BAND CASCADE
com-pressor
1
com-pressor
2
com-pressor
3
com-pressor
4
Ne
t p
res
su
re
Time
LOCAL CONTROLCENTRAL CONTROL
Average pressure
Required minimum pressure
HIGH COSTS LOW COSTS
Energy savings through optimization
ES controls the net pressure– Net pressure is guaranteed while compressors run at lowest required pressure
Lower pressure by 1 bar reduces energy by 7%
30
Automatic selection of “Best Size” compressor
Net pressure drops fast
Net pressure drops slowly
Pre
ssu
re
Time
Pre
ssu
re
Time
Big compressor
Small compressor
31
Efficient?
Optimization of VSD compressors
VSD 2: ~ 70%
Local control
Flo
w
Time
VSD 2: 50%
VSD 2: ~50%
ES optimization
Flo
w
Time
VSD 1: 30%
SE
R (
J/l)
Flow (l/s)
VSD 1 VSD 2
SE
R (
J/l)
Flow (l/s)
VSD 1 VSD 2
32
Optimization of Turbo’s and VSD
Efficient?
Local control
SE
R (
J/l)
Turbo 2
Turbo 1
SE
R (
J/l)
Flow (l/s)
VSD
SE
R (
J/l)
Flow (l/s)VSD
Blow-off SE
R (
J/l)
Turbo 1Blow-off
Turbo 2
Flo
w
Time
Turbo 2: 50%(blow-off ~20%)
Turbo 1: 100%(blow-off 0%)
VSD 2: 90%
ES optimization
Flo
w
Time
Turbo 2: 80%(blow-off 0%)
Turbo 1: 100%(blow-off 0%)
VSD 2: 50%
….. …..
33
Carbon ZeroThe unique approach
coretechnology
drivetechnology
efficient air treatment
optimizationof the room
demandassessment
‘Carbon Zero’
“net zero energy”
The new milestone
Recovery
34
Measured parameters TÜV test
35
Type test of ZR 55-750 range with built-in energy recovery systemsType test of ZR 55-750 range with built-in energy recovery systems
Comparison of the electrical energy consumption with heat energy recoveredComparison of the electrical energy consumption with heat energy recovered
Certified results “100% of the electrical energy
consumed could be recovered” “ net power (energy) consumption of
the ZR compressor with built-in energy recovery at specific design conditions is zero”
Certified results “100% of the electrical energy
consumed could be recovered” “ net power (energy) consumption of
the ZR compressor with built-in energy recovery at specific design conditions is zero”
36
Introducing Carbon Zero
Electrical energy input converted
to heat
10% losses in radiation, etc.
Direct energy recovery 90%
Energy in atmospheric air
(latent heat)
Atmospheric energy 12%
102
Result – Net Zero energy consumption
Released due to condensation in coolers
100%
15%
37
Carbon Zero principal build-upZR Energy recovery
ZR Energy recovery
Oil cooler
HP element
LP element
Aftercooler
Intercooler
Thermostatic valve
ER control unitWater circuit
42%
37%
9%
12%
Recovered energy at 10 bar(e) (145 psig)
20-40°C (68-104°F)70-90°C (158-194°F)
38
Components of the energy recovery systems
H H
H
HT
T
TI
PI
H H
H H
Control unit scope is within the dashed line. Outside is customer’s scope.
H
Heat consumer
ZR
Secondary cooling
water system
39
What makes ZR compressor unique
Compared to oil-injected screws– ZR compressors have much higher temperatures due to which they can recover 100% of
the electrical energy as heat, under design conditions. Watercooled OIS can recover +/- 70%
Compared to turbos– Lower temperatures in turbos restrict energy recovery severely
– Interstage energy recovery can create instability
– At reasonable temperatures energy recovery is 30-35%
Compared to other oil-free screws– Others are not recovering energy from oil coolers and jackets, thus losing 20-25%. So
energy recovery with competitors OFS could be at best 80%
40
Applications
Space heating
Showers
Boiler feed
41
Some high level steam applications
42
Example of savings with Carbon Zero
Consider a ZR132 kW compressor and an energy recovery of 135 kW
Heat equivalent per second = 135 kJ/s
When using heating oil (HO)
Calorific value = 41,200 kJ/l
Boiler efficiency = 70% without recovery and 90% with recovery
Heat generated per hour = 135 kJ/s x 3600
Fuel saved = 135 x 3600 / (41,200 x 0.9) = 13 l/h = 3.4 gal/h
Cost of fuel = 0.5€/l x 13 l/h = 6.50 €/h = 8 $/h
Yearly savings = 6.5€ x 8000 h/y = 52,000 € per year = $ 64,000 per year* Calculation based on full load running for 8000 hours – full potential
43
Carbon Zero ZR range
270 m³/h 7,470 m³/h
4 bar(e) 58 psig
10.4 bar(e) 151 psig
ZR 55 – ZR 750
ZR 75 VSD – ZR 700 VSD
159 cfm 4,387 cfm
44
Conclusions: Energy Efficiency in CAS
Reducing air leaks– Ultrasonic leak detection
Overall system design– System audits and simulation
– Optimal compression technologies
– Control and ancillary systems
Use of adjustable speed drives (ASD)– Variable Speed Drives
Recovery of waste heat– Carbon Zero compressors recover up to 100%
Atlas Copco approach
45
Committed tosustainable productivity.
46