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M.B.T. Simple Process Flow Chart
2
Mechanical sorting
& pre-treatment
Biological
treatment
M.B.T. + Anaerobic Digestion + B Diagram – HassePlant
Principal Waste Management Options
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Waste
Landfill Thermal Recycling Biological
Incineration Gasification Pyrolysis AnaerobicDigestion
Composting
With EnergyRecovery
WithoutEnergy Recovery
Waste Technology Reviews & Case Studies carried out by the Enertech Team since 2002
World Wide
� Anaerobic Digestion 98
� Autoclave Processes 10
� Biological Aerobic Processor 17
� Gasification Processes 64
� Pyrolysis Processes 18
� Plasma Gasification 14
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The Future Energy Centre
MSW LIQUID WASTE
WASTE REDUCTION AND
SEPARATION
FARM WASTES
FOOD PROCESS WASTES
CHP
GAS CLEAN-UP
PLANT
Anaer obic Digest er
(Far m Wast e)
Anaer obic Digest er M.S.W. CO2 FOR
INDUSTRIAL PROCESS
EXISTING LANDFILL
ELECTRICITY TO GRID
CH4 HEAT
BY PRODUCTS DAY COVER
BY PRODUCTS TO FARMS
BIOGAS
HEAT
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advanced digestion technology
Bioenergy from AD in the UK
Dorian Harrison, Technical Director (Monsal)
Presented by, Gerald Tetchner of Enertech
Introduction
• Why AD gets such good press• Government support for AD• Market segments for AD• Types of AD Plant
Positive PressPublic Perception
• Perceived as natural• Recycling of organic waste• Recycling of Nitrogen and Phosporous• ‘Carbon neutral’• Flexible Technology (gas / elec / heat)• Easy to understand
– ‘it’s a cow!’
Positive PressPublic Perception
• 500 – 600 anaerobic digesters in UK now• Most towns have an AD plant (sewage)• Operational for >100years
SORP
Positive PressEconomic and Political
• Recycles organics away from landfill• Smaller more local plants• Renewable energy targets
– electricity
– gas– heat
• Coalition agreement
Positive Pressdigestate
• PAS110 – product• AD ‘Recycling’• Fertiliser
AD UptakeEconomic and Political
• Feed in Tariff • Renewable Obligation Certificates• Renewable Heat Incentive• Renewable Transport Fuels Obligation
Government SupportROCs
• AD 2X ROC (~ £90/MWh)• Sewage sludge only 0.5 x ROC• Sell Price ~ £30/MWh• 30,000tpa ~ £1.2M (revenue)
Government SupportFeed in Tariff
• Plants <500kW = 11.5p/kWh• Plants >500kW = 9p/kWh• Fast track revenue
– <250kW = 14p/kWh
– >250 – 500kW = 13p/kWh
• 30,000tpa ~ £1.2M
Government SupportRenewable Heat Incentive
• 6.5p/kW for Biomethane• 6.5p/kW (upto 200kW)• Open to all digestion including sewage• 30,000tpa ~ £1.4M
Monsal EEH Avonmouth
Technologywhat is anaerobic digestion
Buffertank
sludge
Waste
and/or
Boiler orgenerator
Water/sludgeheat exchanger
Recirculation
Digested sludge
Anaerobic digester
Technologyhow does it work
• All AD process follow this route• Multi stage process optimise
• Various stages can be optimised or inhibited
Monsal EEH Bromborough
TechnologyTypes of digestion plant
• Agricultural (£1M - £3M / ~6 months)
• 6K – 20K tpa• Simple
• No Permit (Usually)
• No Waste Licence
• Merchant (£6M - £10M, 18 - 24 months)
• 20K – 80K tpa
• Remove Contamination • Compete for Waste (Lowest Gate Fee Wins)
• Requires IPPC Permit, ABPR, Planning
• Municipal (£30M+, PFI ~ 2 – 5 years)• 70K – 300K tpa
• Recycling Facility
• Very Heavy Engineering• MRF + AD Plant
• Permit + Animal Health + Planning + + +
Monsal - Waterbeach
TechnologyAgricultural (crops grown 2009)
• Wheat– 14,379– 108% of UK requirement
• Barley– 6,769– 112% of UK requirement
� Total Cereal– 21,197,000 (dry) tpa– 104% of UK requirement
� Excess of 815,269 (dry) tpa
Monsal Bioenergy – Car Farm
TechnologySewage Sludge
• Sewage– 30,000,000 (wet) tpa
– 1,600,000 (dry) tpa
– 60% already treated by AD
• Challenges– relatively low energy value– low dry solids concentration
– 40% sewage sludge not digested
Monsal - Crewe
TechnologyFood / C&I
• Food and Drink Industry– 1,800,000 (dry) tpa
• Retail Outlets– 400,000 (dry) tpa
• Other (Schools / Hospitals)– 1,000,000 (dry) tpa
• Issues– diverse wastes (solid / liquid)– dispersed production sites– De-packaged is essential
TechnologyFood, C&I – waste streams
• Supermarkets / Retail• Manufacturing• Hospitality• Service Industry
• Council collections
TechnologyFood, C&I – de-packaging
Food Waste Digester FeedWaste pulping/screening
De-packaging is essential to prepare the feedstock for effective digestion
Technologytypes of AD plant
(AN Digestion)
(Biogen Greenfinch) (Kompogas)
(Monsal)
Feed Stock Arisingwhat is the potential
Source Wet tpa Dry tpa Biogas yield
Biogas
Mtpa Mtpa m3/dryT m3/year 106
MSW 30 2.2 700 1,522
C&I 12.8 3.2 700 2,240
Slurries 4.0 1.0 500 500
Crops NA 0.8 600 480
Sewage 30 1.6 350 560
Total 76.8 8.0 5,302
Energy Valuehow much energy is there?
Source Biogas CH4 CH4 Energy
106 m3/year % 106 m3/year TW
MSW 1,522 62 944 9.4
C&I 2,240 62 1,389 13.9
Slurries 500 62 310 3.1
Crops 480 55 264 2.6
Sewage 560 65 364 3.6
Total 4,822 3,006 32.6
Energy Valuehow much energy is there potentially?
Source Biogas CH4 CH4 Energy
106 m3/year % 106 m3/year TWh
MSW 1,522 62 944 9.4
C&I 2,240 62 1,389 13.9
Slurries 500 62 310 3.1
Crops 480 55 264 2.6
Sewage 560 65 364 3.6
Total 4,822 3,006 32.6
Energy Valuehow much energy is there really?
Source CH4 Potential Reality?
106 m3/year TWh TWh
MSW 944 9.4 4.7 (50%)
C&I 1,389 13.9 7.0 (50%)
Slurries 310 3.1 0.3 (10%)
Crops 264 2.6 2.1 (80%)
Sewage 364 3.6 2.9 (80%)
Total 3,006 32.6 17.0 (52%)
Technology types of anaerobic digestion
• ‘Wet’– Digester feed <15%DS– CSTR Reactors– Food Waste– Sewage Sludge– Agricultural Waste
Monsal Biowaste - Deerdykes
Technology types of anaerobic digestion
• ‘Dry’– Digester feed >15%DS– Plug Flow Reactors– Garden Waste– Green / Food (mixed)
Kompogas Dry Digester
Technology types of anaerobic digestion
• Mesophilic– Range 25C to 42C– Normal 35C to 40C– 99% of UK Digesters
• Thermophilic– Range 52C to 65C– Normal 55C to 62C
– More Common for Dry Digesters
Conclusion
• AD has positive public perception• AD is uncontroversial in Government• Strong incentives to drive AD growth• Relatively simple technology• Large infrastructure investment required
advanced digestion technology
Questions?
Dorian Harrison
Technical Director
t: 01623 429500
