BIOGAS – DECENTRALIZED ENERGY SUPPLY FROM LOCAL AND RENEWABLE RESOURCES International Conference on “Integrated Resource Management in Asian cities: the urban Nexus” Visions, best practice, experience sharing Bangkok, 24.-26. June 2013

Dr.-Ing. Martin Wett Süddeutsche Abwasserreinigungs-Ingenieur GmbH www.sag-ingenieure.de (englisch) [email protected]

Abwasserreinigungs-Ingenieur-GmbH Sachsen www.sag-sachsen.de [email protected]  sewers  waste water treatment  sludge treatment  energy GERMANY Ulm  Heidenrod  Karlsruhe  Schramberg  Wiesbaden Würzburg  Dresden  Hamburg AUSTRIA Graz

Biogas in Germany

renewable energy _________________ political framework

Global energy issue‘s

Nature Can’t Handle Our Growing CO2-emission

 Time to change our way to produce energy

German legislation aim‘s Renewable energy resource act (EEG)

wind energy

biogas / thermal

water power

solar energy

German legislation aim‘s support : use of local and renewable ressources waste management

forestry

agricultural

sanitary engineering

energy industrie (solar, biogas, windpower,)

effects:

 climate protection by reducing CO2-emissions !  Increasing local net product!  new local working places!!!

German legislation aim‘s Renewable energy resource act (EEG)  biogasplants in germany Total installed electrical power

 2.900 MWel.

wind energy

biogas / thermal

water power

solar energy

German legislation aim‘s Renewable energy resource act (EEG)  biogasplants in germany All-rounder biogas

 energy on demand

wind energy

biogas / thermal

water power

solar energy

German legislation aim‘s Renewable energy resource act (EEG)  biogasplants in germany All-rounder biogas

 enables base load energy supply

German legislation aim‘s Renewable energy resource act (EEG)  biogasplants in germany

Biogas in Germany

biogas _________________ input ressources and technology

Biogas in Germany – input ressources BIOGAS in GERMANY as result of

organic waste (commercial and indusrial)





food residue



market waste

residues from poduction processes (e.g. bee, sugar, wine, milk, alcohol, juice, meat, products, vegetables pocessing) 

fat

waste from landfills



sorted organic fractions from waste treatment (MBT)

organic municipial waste

agriculture



sewage sludge



manure



municipal solid waste



residues

 landscape care



energy crops

Biogas in Germany – input determines technology Technology alternatives in anaerobic digestion Wet anaerobic digestion

Dry anaerobic digestion

 Biogas plants for pumpable organic matter

 Biogas plants for nonpumpable organic matter

 Main focus: energy crops, manure, slury

 Main focus: municipal organic waste, agricultural residues Target groups:  Waste management industry /compost facilities  Food processors  Municipalities  Energy providers

Target groups:  Farmers: Dairy and livestock farming  Energy providers  Public services

Biogas low-tech-solution – wet anaerobic digestion Turning organic liquid or waste with dry solid content 40% to valuable energy  Stackable substrates like yard waste and bio waste are the main material source for dry fermentation  Even low quality material can be utilised  Profitable material management, instead of expensive waste disposal  No tank-to-plate discussion since only waste products are utilised  No dependence to substrate supplier like agricultural  average specific bio waste yield = 126 kg/people/year  shielded against price fluctuations  Digestate comes as a high class fertiliser  No disposal – but production fertiliser, soil conditioner  Biogas is cleaned and grid injected or combusted in CHP

Biogas in Germany – dry anaerobic digestion Typical plant configuration

Biogas in Germany – dry anaerobic digestion Process design of a biogasplant with CHP Unit

Biogas in Germany – dry anaerobic digestion Process design of a biogasplant with CHP Unit The advantages of this dry anaerobic digestion process is: 1.No rotating parts like agitators 2.No pre-treatment like silaging 3.The system tolerates impurities such as plastic, metal or wood 4.Low parasitic load 5.No additional water is needed 6.High methane yields, low sulphur content 7.High degree of degradation  A small portion (ca. 5%) of the generated heat is used as process heat in the plant (in floor radiant heat of digester, heating of building or similar)

 The surplus heat is available for use externally  In the case that the heat cannot be utilized - the CHP or biogas boiler have emergency cooling equipment

Biogas in Germany – dry anaerobic digestion Reactor configuration  Rectangular, side by side reinforced concrete containers with a floor area of 7 x 30m in which the stackable charge materials are digested  Mixing or other production related processing is not necessary

Biogas in Germany – dry anaerobic digestion Opening of the fermenter after 28 days

 No free water  No smell of volatile fatty acids  Organic fraction is broken down form 90% to 50%

 Total solids went down from 30% to 17%  Charging and emptying of digester with a front loader or similar equipment  The plant is completely controlled via an SPS control system  Malfunctions are identified by the control system, registered and the plant operator is notified

Biogas in Germany – dry anaerobic digestion Ground plan – 6 fermentation chamber biogas plant (190 kWel.) size digester: 20m * 7m * 5m (L * W * H)

percolate 250 m³

Chp

Biogas in Germany – capital costs Reactor configuration Wet anaerobic digestion

Capital costs:  3.000 – 5.000 € / kW el. Installed

Dry anaerobic digestion

Capital costs:  4.000 – 6.000 € / kW el. installed

Substrate input  electrical output : 5.000 people  4.000 – 5.000 t biowaste  190 kW el.

Biogas in Germany – impressions Biomethane plant aiterhofen – 11,4 MW gas Owner: E.ON Bioerdgas GmbH Raw gas input: 2.000 m³/h Processing capacity: ca. 10 Mio. m³/year Injection capacity/year: 100 billion kWh in natural gas grid Input: Maize silage, WCS, grass silage, catch crops Gas grid: Energienetze Bayern Utilisation: Operation of decentralized CHP by E.ON Commissioning: September 2009

Biogas in England – impressions Biogas plant Stoke Bardolph – 2,12 MWel Customer: Severn Trent Water Ltd., England Installed electrical output: 2 x 1063 kWel Input: Maize silage, whole crop silage Commissioning: May 2010 Utilisation: The generated electrical and thermal energy is used for a neighbouring sewerage treatment plant operated by Severn Trent Water Ltd. Excess electrical energy is fed into the public grid.

Biogas in Germany – impressions Biogas plant fischbach (agricultural plant) – 0,185 MW gas Customer: Farmer Johann Mayer Installed electrical output: 185 kW Input: 3.500 t Beef slurry 1.700 t Grass silage 1.700 t Maize silage 400 t Solid pig manure Commissioning: December 2009 Utilisation: The generated electrical energy is fed into the public grid.

Biogas in Germany – impressions Biogas plant Allendorf (eder) – 0,185 MW gas Operator Viessmann Biomasse KG Location Allendorf, Germany Input material 7.000 t Green waste and yard waste Comissioning August 2010 Utilisation: The generated electrical energy is fed into the public grid. Thermal energy is used in a local district heating network, to provide heat to the Viessmann headquarter as a part of the Efficiency Plus initiative.

Biogas in Germany – impressions Biogas plant Moosdorf(eder) – 0,84 MW gas Operator BIOMethan Moosdorf Location Germany Input material 9.000 t biological waste 7.000 t green waste Comissioning August 2007

biogas _________________ decentralized energy supply for bioenergy villages

Biogas in Germany – decentralized bioenergy villagec

Biogas in Germany – decentralized bioenergy village bird view on biogas plant (840 kW el.)

fermentation-residue repository pit storage fermenter/digester

separated fraction of solid matter

plug-flowfermenter/digester

feeder

block heating station

Biogas in Germany – decentralized bioenergy village Drying (Heating) plant as part of the biogas plant

Biogas in Germany – decentralized bioenergy village bird view on biogas plant (840 kW el.)

Heating net:  length: 11.314 m  Capacity: for 300 housholds  Considered heat loss: 25%

Biogas in Germany – decentralized bioenergy village Heat supply cascade concept

sorted annual heat load curve

peakload-vessel (xx)

wood-pellet-vessel (xx)

water-buffer heating net chp biogasplant and satelite chp yearly operation time

Biogas in Germany – decentralized bioenergy village pelletitzing and drying of solid fermentation residues and use as fertilizer/combustible

fermentation residue pellet‘s

straw pellet‘s

Biogas in Germany – decentralized bioenergy village Environmental effect of biogas

 CO2-reduction 4,800 tpy = 30% of today‘s CO2-emission of Wettesingen !!! electricity

CHP heat

 Production of electricity for 7,000 people (about 2,000 private households) !!!  Heat production for 300 privat houses !!!

biogas _________________ biogas in gas grids

Biogas in Germany – decentralized bioenergy village Typical plant configuration

plant for biogas upgrading by pressure swing absorption (PSA)

biogas _________________ biogas as fuel car

Biogas in Germany – decentralized bioenergy village Biogas as car fuel

biogas _________________ sewage sludge drying

Biogas in Germany – centralised sludge drying

Use of biogen waste for sewage sludge drying within a county with 170.000 people

Biogas in Germany – centralised sludge drying Future sewage sludge disposal concept  Semicentrale dewatering on 5 wwtp with  Centralised sewage sludge drying and sludge degasification to ash  enery ressoruce for drying local biogene waste: biowaste, leftover foodstuff, wood from landscape conservation  Intelligent coupling of local waste and energyconcepts

Biogas in Germany – centralised sludge drying ANAEROBE VERGÄRUNGSANLAGE

1.) biowaste

Use of wood in thermal heating station

2.) leftover foodstuff

from landscape conservation

3.) wood from landscape conservation 4.) Abfälle aus der Landwirtschaft

drying of grain Anaerobe Vergärungsanlage

wood

sewage sludge drying

wood heating

Landwirtschaftliche Reststoffverwertung

gain concept :

gain concept:

gain concept :

sale of residues as fertilizer or pellet

sale of heat in heat grit

drying of grain

ENERGIEMANUFAKTUR

biogas project realisation

_________________

decission process

Biogas projects – decission process  should you transfer your biogas with a biogas grid to the point of usefully use ?  which substrate ressources you have (municipal, industrial, other) ?

 which biogas technologie is appropriated ?  what is your financial budget ?

what can you do usefully with heat?

 can you combine biogas with other technologies to realise decentralised energy supply solutions ?

 there is no need to do something but something usefull

THANK YOU FOR YOUR INTEREST !

june 2013