Data Archiving and Networked Services (DANS) · 2006 · 16 citations · 4 references
EngineeringChemical EngineeringEnvironmental EngineeringCatalysisDownstream ProcessingSolid Waste ManagementAnaerobic DigestionBiofuel ProductionBiogas ProductionBiomass ConversionBiomass Energy SystemsEnergy ConversionAnaerobic Digestion ModelingBiogasBiogas GenerationDry StreamsFuel EconomyGasificationNatural GasRenewable Fuel Pathways
”Green Gas” as SNG (Synthetic Natural Gas) can play an important role in the transition process from the present Dutch fossil fuel-based energy supply to a renewable fuel-based economy. Anaerobic digestion and supercritical water gasification have been assessed for SNG production from wet biomass streams. For relatively dry biomass streams steam-blown indirect gasification, pressurised oxygenblown gasification, hydrogasification, and co-production of both Fischer-Tropsch diesel and SNG have been considered. All cases with upstream gasification are followed, after gas cleanup, by a downstream methanation step. Although upgrading of landfill gas, or biogas produced via anaerobic digestion of wet biomass, will be interesting for the short-term introduction of “Green Gas” in the Dutch energy supply, the supercritical water gasification processes seem to be more promising for conversion of wet biomass to “Green Gas” on the longer term. Based on the modelling results, the upstream-pressurised oxygen-blown CFB and indirect atmospheric steam-blown gasification with downstream methanation routes were identified to be the most promising options for stand-alone SNG production from relatively dry biomass feedstocks. In combination with downstream methanation, SNG production efficiencies up to 70% (LHV) can be achieved. The successful integrated lab-scale demonstration of “Green Gas” production confirmed the potential of the ECN gas cleanup concept to deliver a product gas that can satisfy, among others, the specifications for downstream methanation. For 100 MWth stand-alone systems and biomass costs of 2.3 €/GJwood, the SNG production costs range from 7.8 to 8.5 €/GJSNG and the CO2 emission reduction costs range from 83 to 95 €/tonne. “Green Gas” production via biomass gasification with downstream methanation will become an economic feasible process in the Netherlands, when “Green Gas” receives the same tax exemptions as currently are given to green electricity.
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