1. ECSM 2010 – 2nd European Conference on Sludge Management
Budapest, Hungary 9 & 10 September, 2010
SEWAGE SLUDGE AS RENEWABLE
ENERGY
István Zsirai
Vice President, Global Supply Chain,
GE Power & Water,
Water & Process Technologies,
Trevose, US
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
2. Sewage Sludge as Renewable Energy
1. SEWAGE SLUDGE VOLUME INCREASE IN THE EU REGION
2. CURRENT STRATEGIES AND APPLIED TECHNOLOGIES TO HANDLE
ORGANIC SLUDGES
3. SEWAGE SLUDGE AS RENEWABLE ENERGY
4. FACTORS INFLUENCING FUTURE SLUDGE HANDLING STRATEGIES
5. DISCUSSION/CONCLUSIONS
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
4. Sewage Sludge volume increase in the EU Region
Sludge Production Volume Tds/a In the Member States of EU the agriculture
Countries
2010 estimate 2020 estimate usage of sewage sludge reaches 42% avg. and
USA 7.000.000 10.000.000 there are more than 7 countries within the EU27
Austria 273.000 280.000 where the usage is beyond 60% in agriculture.
UK 1.640.000 1.640.000 There are also more than 7 countries with less
Scotland 200.000 200.000 than 3% up to zero. Sludge is applied to less than
Spain 1.280.000 1.280.000 5% of agriculture land in EU and contributes <5%
Sweden 250.000 250.000 of the total amount of organic manure used.
France 1.300.000 1.400.000
Germany 2.000.000 2.000.000
Many states have stopped the Sludge to Land
Italy 1.500.000 1.500.000 recycling in the last 5 years.
Romania 165.000 520.000 The EU Sewage Sludge Directive was adopted
Portugal 420.000 750.000 more than 20 years ago with a view to encourage
Poland 520.000 950.000 the application of sewage sludge in agriculture
Hungary 175.000 200.000 and to regulate its use as to prevent harmful
EU27 11.500.000 13.500.000 effects on soil, vegetation, animals and humans .
EU27 2010 distribution estimate % EU27 2020 distribution estimate %
Recycled to Land Incineration Landfill Other Recycled to Land Incineration Landfill Other
42 27 14 16 44 32 7 16
Global Sludge Production > 50M Tds/a
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
5. Expected Trend for the next 10-30 years
• The population of the EU will grow slowly, from about 499 million in 2010 to just
under 514 million in 2020 (according to Eurostat projections)
• While industrial production will grow, process improvements, pollution prevention
and improved on-site treatment will reduce sludge coming from industry.
• Continued increased level of sewer connection and wastewater treatment across
the EU27, which means more sewage sludge being produced which will need
proper sludge management.
• Increased industrial water pre-treatment and pollution prevention, reducing or
eliminating discharge of toxic substances (heavy metals, chemicals) and
improving sludge quality.
• General phasing out of sludge being sent to landfill due to EC restrictions.
• The use of raw sludge will be no longer accepted, sludge shall be treated.
• Due to global population growth ( to 8 billion/2030) the demand for clean water
will be trippled and the demand for electricity will have two folds growth.
• Main alternative to „sludge to land” is likely to be incineration with energy
recovery.This will compensate landfill disposal discontinuation.
• Due to Climate Change Policy and Renewable Energy Policy the sludge
management will be influenced with novel technologies like AAD, Gasification,
Pyrolysis, Fuel Crops, SCWO, Incineration,Biodiesel, Bio-hydrogen,etc.
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
6. Global 2030 needs
62.2
Billions of kW hours (In billion cubic meters)
2x Electricity 3x Water 50.2
40,000
Emerging
35,000 Developed
30,000
20
*at same consumption rate
19.9
25,000
20,000 15
15,000
10
10,000
5
5,000
0 0
2008 2010 2015 2020 2025 2030
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Ja ia
ria
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Ru n
Fr a
Sp l
Al ia
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in
az
pa
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an
ab
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In
Ch
Ko
Br
i Ar
ud
Sa
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
8. Approved method for stabilization/disinfection in sludge
Source:Ødegaard, H., Paulsrud, B., Karlsson, I.
“Sludge disposal strategies and corresponding treatment technologies aimed at
sustainable handling of wastewater sludge”, 2010
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
9. Multiple-stage utilization of sewage & organic sludge
Regional/rural
Sewage transported sludge
Road transport Organic food waste water
(fecalia)
Sewage Treatment Plant
Wastewate treatment Sludge handling
Concentrated raw sludge
Brown coal and/or
Dewatered
sludge
lignit coal
Treated wastewater
I. Anaerob
injection
Solar digestion
dewatering biogas-energy
drying production
Digeste
sludge
d
Composting
Agricultural utilization
Irrigation - Sludge disposal
Bioethanol, Biodiesel flora Energy Flora *
rape, maize, sweet sorghum, Other agricultural utilization
process
Dr. Stadler patented
elephantgrass, sunflower, built environment energy grass energy forest*
energyhemp, chinese reed stb
* sludge disposal only in the year of planting
II. Biomass
Liquid fuel production
heat + electric energy production
Heat energy prod.
Electric energy prod.
l
l
III. Pelet, briquette, compost fuel production
heat + electric energy production
Source: Endre Juhász dr. publication, 2007.
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
11. Renewable Energy generation from Sewage
Source: Parliamentary Office of Science and Technology, UK
April, 2007 number 282
Modified by Istvan Zsirai
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
12. Aqua Citrox® SWCO technology (Chematur Eng.AB)
Under normal conditions, water is seen in any of its three states:
steam, liquid water, or ice. If water is heated and compressed to
sufficiently high temperature and pressure, water enters a 4th state
known as the super critical state. In the case of water this occurs
above 374 °C and 221 bar
In the reactor oxygen is injected to start the
oxidation reaction. The reaction is exothermic
and temperatures increase as the reaction
progresses. After passing through the reactor
the effluent flows through the economiser
where it heats the incoming stream. In larger
plants the heat of reaction can be recovered
via a steam generator for power generation.
District heating is also an option depending on
the plants location. Following any heat
recovery the effluent is cooled to its exit
temperature by a cooler prior to passing
through the pressure reduction system where
the pressure is lowered to <10 barg. The
effluent then passes to a gas /liquid separator
where the CO2, N2 and residual O2 are
separated from the liquid stream. The
inorganic residue is removed from the liquid Source:
J. O’Regan, S. Preston, A. Dunne:
stream. This stream has a COD of <5mg/ltr. Supercritical Water Oxidation of Sewage Sludge
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
13. Sludge Gasification Process ( Primenergy LLC.)
Source: Primenergy, A Safe Alternative
The steps in this integrated process design are:
1. High moisture content sewage sludge at 25% solids, either digested or undigested, is introduced into a thermal dryer. The
two common types of dryers are direct contact, which uses heated air as the drying medium, or indirect contact, which uses
steam or heated oil as the drying medium.
2. Dried biosolids are discharged from the dryer. Moisture content is reduced to approximately 10%, creating a quality
biosolids fuel.
3. The dried biosolids are fed into the gasification and energy conversion process.
4. The remnant ash is discharged from the gasification process. At this point over 85% of the weight of the wet sludge has
been removed.
5. The synthesis gas is oxidized in a series of stages and the released thermal energy is captured either in heated air or in the
production of steam.
6. The thermal energy is directed to the dryer, providing the energy necessary for the evaporation of the moisture contained in
the wet sludge.
7. Environmentally compliant dryer exhaust, spent productions of combustion and moisture, are vented to the atmosphere.
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
14. Global Renewables
Wind & Solar PV annual installations
(GWs) 55 CAGR
Wind
Wind ~41%
40%
40%
GR 37
CA
Solar PV
Solar PV 24%
<1% ~22%
<1%
Concentrated
Concentrated 17
Solar <1%
Solar <1% Solar
PV 8
4
Wind
‘00 ‘03 ‘06 ‘09 ‘12
Biomass
Biomass Source: REN21 2006 update + EER
19%
19%
Sewage Sludge to Energy
Small hydro
Small hydro will grow drastically in the next
32%
32%
20 years and get significant %
Sludge on the Renewable Energy map
Tidal
Tidal ?%
<1%
<1%
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Geothermal
Geothermal Focusing on electricity growth rates
Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
<1%
<1%
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
15. Sludge to Energy
Global production of Sewage Sludge exits 50M Tds/a
Raw Sludge 25.5 MJ/kgds [ 100 %]
Surplus active sludge 20.9 MJ/kgds [ 88 %]
Digested raw sludge 11.6 MJ/kgds [ 45 %]
Digested mixed sludge 13.4 MJ/kgds [ 52 %]
Biobriquette, biopellet app.14.0 -18,0 MJ/kg [~ 63 %]
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
17. Factors Influencing Future Sludge Handling Strategies
1. Legislation, Law Enforcement
• EU Urban Wastewater Treatment Directives, EU Waste Management Licensing Regulation
• EU Water Framework Directives, EU Sewage Sludge Directives
• EC Bathing Water Directive, EU Animal By-product Regulation
• EU 20-20-20 Directives, EU ETS & CCA’s,EU Directives on Renewable Energy
• Kyoto Protocol,reduction of GHG emission, Upcoming Regulation on EDC’s.
2. Economical incentives
• Government fundings, special incentives for Renewable Energy investments
• Water-Energy Relationship
• Energy and Sewage Relationship
3. Public concerns, acceptance
• Odour, dust, noise of traffic movement
• Problems of potentially toxic elements (PTEs) in sewage sludge
• Sewage sludge contains a number of volatile organic compounds
• Environment quality goals for a poison-free environment
4. Technology development
• Beside of implemented incineration and biogas generation processes there are lot of novel
technologies on market offering more benefits, better and easier sludge handling
• Leading global companies are developing and implementing new sludge mgmt processes
• Sewage Sludge is a new target for renewable energy generation
5. Product development
• There are matured product on market enabling to turn sludge to energy in an economic way
• Jenbacher generators
• Anvanced Anaerob Digestion
• SWCO
• Etc…..
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
18. EU 20-20-20
Reduction of GHG by 20%
Increase Renewable Energy ratio by 20 %
Decrease primer energy usage by 20%
1. Speed up the coal free energy implementation
Mandatory target of EU to achieve till 2020 minimum 20%
Renewable Energy ratio in the total energy mix. For the Bio-Diesel ratio
there is a special target a minimum 10% , which shall be achieved..
2. Energy efficiency
As per the Commettee the primer energy usage shall be
decreased by 20% till 2020.
3. GHG reduction
As per the Commettee the GHG emission shall be reduced by
20% till 2020.
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
20. GE is a world leader in renewable energy solutions
Wind
EFS Solar
ecomagination
ecomagination
Jenbacher
$5B invested since ‘02
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
21. Jenbacher gas engines
A leading manufacturer of gas-fueled reciprocating engines for PG
• Power range from 0.25MW to 4MW, 4 platforms (Type 2, 3,4 & 6) / 11
products
• Generator sets, cogeneration systems, container solutions
• Delivered engines: about 8,500 units / ~10000 MW
• Diversified customer base: farmers, small Industries, Commercial buildings,
IPPs, utilities …
• ,
Service offerings: CSA’s,T&Ms,parts,repairs upgrades,Remote diagnostics
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
22. Jenbacher solutions
Landfill Gas Biogas
1MW saves 5,000 cows
32,000 CO2 fuel 1MW
tons/y
(eq. 15,000 cars)
Coal Mine Gas Cogeneration
1MW saves J624 (4MW)
32,000 CO2 avoids 32,000
tons/y barrels of oil
Approx. 70% of JB …..
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
24. Conclusion
The Sewage Sludge is not waste, rather a potential
source of energy, throught its components is such a
Raw Material, which directly or indirectly – via
appropriate changeover – able to replace or to
complement primer materials (chemical fertiliser)
and/or energy (termal, electrical) !
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010
25. Key Takeaways
• Focus on „Sludge to Energy”
• Energy objectives to Sewage Treatment
• Sludge is a growing part of Renewable Energy
• Sludge might effect the EU 20/20/20 results
• $30B market by 2020
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Sewage Sludge as Renewable Energy ECSM 2010 – 2nd European Conference on Sludge Management
Istvan Zsirai Budapest, Hungary, 9&10 September, 2010