opportunities and barriers for efficient energy use in a medium … · 2012-04-16 · opportunities...
TRANSCRIPT
Opportunities and barriers for efficient energy use in a medium-sized brewery
B. Sturm Sir Joseph Swan Centre for Energy Research, Newcastle University
Thermal Energy Management in the Food and Drink Industry
Introduction
1. History of Brewing
2. Key figures of the British Brewing Sector
3. The Brewery investigated 1. Key figures
2. Data availability
3. State of the brewery
4. Waste heat recovery
5. Energy generation
6. Barriers to energy efficiency
4. Conclusions
History of Brewing
• Roman-Celtic Britain
• Middle ages
• 1400-1699
• 1700-1899 Industrialisation
Empire
• 1900 to present Megabreweries
Microbreweries
J. Amman, 16th century, The Brewer
Key Figures British Brewing Sector
Source: Hugenschmidt, 2011
0
20
40
60
80
100
120
0
100
200
300
400
500
600
700
800
2002 2003 2004 2005 2006 2007 2008 2009 2010
bee
r p
rod
uct
ion
[h
l 10
6]
per
cap
ita
con
sum
pti
on
[l]
Nu
mb
er o
f b
rew
erie
s
Year
annual production
annual consumption
per capita
breweries
Source: Pattinson, 2010
Beer Sales by Type
Energy Demands in Industrial Breweries
Source: Bonnaccelli et al. 2006
Wort boiling 30.0%
Mashing 30.0%
Packaging 20.0%
Warehouse 2.0%
Utilities 6.0%
Beer Processing 10.0%
Others 2.0%
Brewhouse 48% Fermentation and
storage 9%
Filtration 3%
Filling bottles 26%
Filling kegs 9%
Administrative department
6%
Source: Esslinger, 2009
Distribution of Thermal Energy Consumption
Development of specific energy demand
Source: British Beer and Pub Association, 2005
Energy demand as a function of size
0
40
80
120
160
200
240
1.E+03 1.E+04 1.E+05 1.E+06 1.E+07
sp
ecif
ic e
nerg
y d
em
an
d [M
J/h
l]
annual beer production [hl]
e_el
e_th
Source: Feltschlaeger et al., 2003
Key figures of the brewery investigated
• Commercial brewery since early 18th century
• Current production: 250,000 hl/a
• 15 beers (ales and stouts)
• 90 % “standard“ beer (bottom fermented ale, 3.5 %)
• High gravity brewing
• 24 brews/week
• 195...240 MJ/hl 45...60 MJel/hl (ca. 25 %)
150...180 MJth/hl (ca. 75 %)
• 6.4...7.2 hlwater/hlbeer
Data available for the audit
• Gas and electricity bills • General information on the process and datasheets of
components • Protocols of wort boiling and other process steps
where available • Information from engineering manager and brew
master • Estimations and literature data as well as
measurements where necessary • Problem: statements like “a medium porridge“ are
difficult to quantify
State of the brewery set up
• Conventional gas boiler, no flue gas heat recovery
• Wort boiling Calandria more than 20 years old
Internal structure of copper wrong
No steam recovery
• Insufficient data acquisition
• Automatic process control only in parts of the fermentation and conditioning processes
• New variable power refrigeration system
• No variable speed drives in place
Process set up
Mashing
(65 °C)
Copper
(101 °C)
Fermentation
(20 °C)
Conditioning
(1 °C)
WP
HLT
(80 °C)
Malted grain
Chilled water (4...12 °C)
Trub
Spent Grain
Process Water (68...70 °C)
Steam
6 barBoiler
Hops
Wort
CAL
Water
Steam
Heating 65...101 °C
Steam
Cooling plant
238 kW max
17 % base load
Water
Thermal losses in the process
MT WC WP FV CT Total
0
50
100
150
200
250
300
350
400
He
at
Lo
sse
s [M
J]
Theoretical Energy Demand
0
500
1000
1500
2000
2500
3000
3500
Water (HLT) Wort heating Wort evap. Heat losses
En
erg
y D
em
an
d [
MJ]
Easily applicable measures
• Insulation, where they are worn out or not existing Pipes
HLTs
Vessels
• Enclosure Tanks and Vessels (close lids)
• Use waste heat for space heating, e.g. air compressors
• Use automated process control where it is already installed
Potentials for waste heat recovery and energy consumption reduction
• Boiler Flue gas heat recovery for existing boilers
Condensing boiler
• Copper Vapour heat recovery
Replacement of calandria or even copper
• Motors and Pumps Variable speed drive
Motor size reduction
• Air compressors
• Process control systems
Energy Supply
• Combined Heat and Power (CHP)
• Tri-Generation
• Renewable Energy Sources Solar PV
Solar thermal
Wind
• Energy from Waste Direct combustion (after drying)
Bio gasification
Barriers to Energy Efficiency
• Availability of data
• Lack of time
• High capital expenditures, prioritisation of investment
• Disruption of the production process during the installation period
• Possible Impact on beer flavour
• Possible Impact on beer quality
• New equipment has to be adjusted (to fulfil product specifications)
• Staff must get used to the modified production process
Conclusion
• Great potential for reduction of energy consumption
• Growing awareness and need for changes due to Rising energy costs
Growing pressure to become more sustainable
• Lack of knowledge and/or time to look into energy efficiency measures
• Financial constraints
• Reluctance due to Fear of changes in product quality
Lack of information
Thank You for Your Attention
Questions?