Biogas upgrading Technologies, framework and experience Owe Jönsson, E.ON Gas Sverige Presentation at Biogas Seminar, Fredericia 2008-08-28
Biogas as vehicle fuel the driver for biogas injection in Sweden 14500 vehicles in Sweden 2007, 20% market increase Total sales 2007-53 Mm 3 53% biogas in the CNG in 2007 20% increase in biogas sales 2007 Biogas is untaxed, 12,3 c/nm 3 for natural gas
Marketing methane as a vehicle fuel E.ON Gas Sverige AB sells compressed natural gas and biogas at 20 public filling stations in the south of Sweden 6 busdepots 170 GWh/a replacing about 17 million liters of gasoline/diesel 25 % is biogas Target: Supply 400 GWh/year in 2010, of which biogas will account for 25-50 %
ethane filling stations in weden existing filling station 2007 planned filling station 2008-2009 Source: Swedish Gas
E.ON Sverige biogas production 2007 Laholm injection) Norrköping fuel) Kristianstad gas grid) Eslöv injection) Bjuv injection) 20 GWh (grid 10 GWh (vehicle 15 GWh (local 5 GWh (grid 22 GWh (grid 72 GWh
Injection of gas into the gas grid I Laholm 500 nm 3 /h, E.ON Gas codigestion plant operation since 2000 water scrubber Helsingborg NSR and others codigestion plant 350 nm3/h, operation since 2004 PSA plants in 2008-650 nm 3 /h, and 250 nm 3 /h Göteborg, Göteborg Energi injection into the town grid new plant (1600 m 3 /h)in operation 2007 chemical absorption (CIRMAC)
Injection of gas into the gas grid II Bjuv - 600 nm 3 /h, E.ON Gas start of operation in 2007 PSA Malmö 500 nm 3 /h, E.ON Gas Operation since May 2008 PSA (see picture) Falkenberg 600 nm 3 /h(oct 2008), E.ON Gas operation in october 2008 Amine scrubber system (CIRMAC)
E.ON Bioerdgas - Biomethane plant Schwandorf Input material ca. 80.000 t/a (Maize and grass silage) Production of raw biogas ca. 2.000 m³/h Annual biomethane productionca. 90 Mio. kwh/a Gas quality 11,1 kwh/m³ (H-Gas) Start of construction July 2007 Start of production December 2007 Investment ca. 16 Mio.
Schwandorf upgrading with PSA technology Photo: Claus Bonsen, E.ON Bioerdgas
Technical and adminstrative framework Connection of biogas plants Connection fee based on connection cost Connection limit (measurement, upgrading, odorisation) Transport fee Feed in in distribution grid results in reduced cost in transmission grid Quality of biogas injected into the grid Grid owner liable for gas quality in grid Grid owner measures quality Liability for pressure, quality, odorisation etc.
Political framework Gas grid injection Tax exemption for biogas in the gas grid Trading of biogas to specific customers CO 2 -based road tax Reduced tax on company CNG/biogasvehicles Climate investment program Environmental policy for governmental organizations (85% env. vehicles 2007)
Swedish standard for biogas since 1999
Bugs in biogas? 0,25m 3 upgraded biogas 0,4 m 3 natural gas 1m 3 air from school class room
Injection in gas grid Upgrading Propane Gas grid
Large custom design upgrading plants Stockholm, 1500 m 3 /h
Biogas upgrading getting bigger! Malmberg Water, 1250 nm 3 /h
Standardised units Carbotech, Malmö, 500 m 3 /h
Upgrading plants in Sweden 2007 Water wash with regeneration 17 without regeneration 6 PSA 9 Selexol 1 (rebuilt) Chemical absorption 2 Total 35 Several plants under planning First plant in operation since 1992
Water scrubber systems CO 2 -absorption in water Suitable for sites with water readily available Methane losses has to be controlled Growth on packing requires attention Photo: BioMil
Pressure Swing Adsorption Adsorption of CO 2 on active carbon System pressure around 4 bar Sensitive to sulphur and water Erosion in valves and other mechanical equipement
Chemical absorption systems Most common Amine scrubber Regenerated by heating Low methane losses Can be operated at low pressure Handling of chemical on site Corrosion must be controlled Photo: Läckeby Water
Membrane upgrading systems Multiple membranes necessary for NG quality Demonstration plant in operation in Austria, 180 nm 3 /h, since 2007 Waste methane to CHP-unit
Cryogenic systems Technology still under development Potential for CO 2 -recovery Methane may be produced in liquid form
Possibility for CO 2 -recovery CO 2 may be used for Cooling of trucks Cooling in stationary applications Greenhouses Other applications Photo: BioMil
Small scale upgrading Small scale water scrubbing system Photo: BioMil
Upgrading plant investment costs (source: SGC) Investment cost (million SEK) 25,0 Investment cost 20,0 15,0 10,0 5,0 0,0 0 200 400 600 800 1000 1200 1400 1600 1800 Plant capacity, raw gas (m n 3 /h)
Total treatment cost biogas upgrading (source: SGC)
Total upgrading cost 11 25 c/m 3 injected gas Chemica Water PSA Heat demand [kwh/m 3 raw gas] 0,55 l 0 0 Electricity demand [kwh/m 3 raw 0,12 0,29 0,27 gas] Service cost [ c/m 3 raw gas] 0,16 0,16 0,16 Maintenance, supervision [h/year] 150 150 150 Consumables, spares [ c/m 3 raw 0,6 0,4 0,4 Methane gas] losses [vol-%] <0,1 1-2* 1-3* * can be reduced to <0,2% by e g catalytic oxidation
Summary Gas grid injection must be driven by a market demand for biogas Technologies for purification and upgrading are available Small scale upgrading technologies are still not commercial Biogas can be injected without any hazards to distribution grid or public safety General agreements between the gas industry and biogas producers are beneficial for the development
owe.jonsson@eon.se