Bio-SNG (Synthetic Natural Gas)

A global overview of Biomethane for Transport (covering BioGas and Bio-SNG) presented by Deutsches Biomasse Forschungs Zentrum gemeinnützige GmbH at the "From today’s to tomorrow’s biofuels – From the Biofuels Directive to bio based transport systems in 2020; IEA Bioenergy Task 39 Subtask Policy and Implementation Workshop" on June 3-5, 2009, Dresden, Germany

Note: Biogas is produced by anaerobic digestion of organic materials (e.g. manure, organic waste) while Bio-SNG is produced by gasification of cellulosic materials (e.g. forestry residues, energy crops).

Bio-SNG Projects in Europe

Bio-SNG Demonstration of the Production and Utilization of Synthetic Natural Gas (SNG) from Solid Biofuels (Bio-SNG) (TREN/05/FP6EN/S07.56632/019895)

The objective of the "Bio-SNG"-project is to demonstrate SNG (Synthetic Natural Gas) production from solid biofuels and to integrate this Bio-SNG into the existing energy infrastructure (i.e. fuel station for vehicles, natural gas grid). To meet the specifications required for the gas-utilisation in vehicles or the gas-feeding into an existing natural gas grid the produced SNG will be upgraded. Cars will be operated with this upgraded renewable gaseous fuel to demonstrate the powerful application within the transportation sector.

This overall system of SNG production and use options will be assessed comprehensively according to technical, economical and environemtnal aspects, as well as possible contributions within the European energy system. Thereby effects of the commercial implementation of SNG into the energy system will be examined and can be compared with other options to produce transportation fuel from biomass. Also the possibility of heat and power production from solid biofuels will be considered within this overall assessment e.g. by taking into consideration economic advantages beyond the pure fuel production for transport issues.

SNG Demonstration in Güssing

Due to the fact of the excellent NG distribution infrastructure in Europe, SNG produce from biomass would most probably be in a gaseous form. Compressed natural gas (CNG) is a well known automotive fuel. From a Swiss-Austrian consortium a 1 MWSNG demonstration plant has been build up in Güssing, Austria for the complete value chain demonstration from woody biomass to SNG.

Commercial plants are expected to be in the scale from 20 to 200 MW. In the initial conversion step i.e. in the biomass gasification process wood chips are converted into a syngas or more general into a product gas. The FICFB gasification process has operated in Güssing since 2002 for a combined heat and power (CHP) plant and in this time has reached more than 40’000 h of operation. The product gas is delivered at ambient pressure, has a high content of CH4, higher hydrocarbons and tars. This product gas is suitable for SNG production.

The final conversion step consists of three individual steps, i.e. gas conditioning, SNG synthesis and gas upgrading. R&D work over the past 8 years was focused on gas conditioning and SNG synthesis. At the pilot scale it could be proven, that fluidized bed SNG synthesis is possible. Based on the data of this plant, the demonstration plant has been designed and operation conditions for the demonstration plant are selected.

The whole process chain reaches high conversion efficiencies and has the potential for lower investment and lower operation costs than conventional SNG synthesis technology. Tests on a demonstration scale are in preparation in Güssing to confirm these findings and prepare commercialization of the technology.

View poster on SNG production from woody biomass (259Kb PDF)
presented by the Paul Scherrer Institute, PSI at SPM2.

The ECN/HVC Project for BioSNG

ECN ECN has been developing a system for the conversion of dry lignocellulosic biomass into natural gas quality gas: BioSNG or Substitute Natural Gas from biomass. Technology choices have been based on the desire to have large-scale BioSNG plants with high overall efficiency. The ECN concept is based on so-called MILENA indirect gasification and OLGA tar removal.

The ECN concept offers 70% efficiency from biomass to BioSNG. A lab-scale system is available at ECN. A 1 MW pilot system at ECN is under commissioning for the two main parts of the system: the MILENA gasifier and the OLGA tar removal. HVC is a waste company, which is expanding its activities towards renewable energy. Joining the development of the BioSNG-concept perfectly fits in with HVC’s ambitions in the medium and long term. HVC intends to realize two demonstration plants to demonstrate the ECN-concept.

The first demo plant will be a ~10 MW CHP plant to demonstrate the combination of the MILENA and OLGA-processes. This will be operated from 2012. The second demo plant will be a ~50 MW SNG plant in which the MILENA and OLGA are up-scaled and further gas cleaning and methanation will be added. These additional units will be supplied by a large EPC, which will soon be involved in the development.

View Poster on ECN/HVC project ( 1.2 Mb PDF) presented at SPM2.

The GoBiGas project

The purpose of the GoBiGas project led by Göteborg Energie A/B is to build a large scale plant that converts low quality cellulosic materials to biofuel with a conversion rate of more than 60%. The plant will be built as a co-generation plant where most of the losses in the process are recovered, pushing the overall
efficiency to around 90%. It will have a capacity of 20 MW biomethane production, which is enough to supply some 15 000 passenger cars with biofuel. It will be operational in 2011. In a second phase, completed by 2015, the plant will be expanded to 100 MW plant, capacity. The plant will have with a continuous operation of 8000 hours per year.

Biomethane is the 2nd generation biofuel that allows for the highest conversion factors in gasification processes, because it’s the simplest hydrocarbon that exists. It also allows for very efficient transportation through the natural gas grid, because biomethane and natural gas is the same chemical substance, but with different origins. This is already being practiced in Sweden and other Member States.

The project will result in substantial reductions in CO₂ emissions, not only because of the small amounts of fossil fuels used in the WTW chain,resulting in CO2 savings of at least 85% for every unit of fossil fuel displaced, but most importantly it will provide very high CO₂ savings per unit of land used for fuel production. Apart from the difference of yield in the different processes, the use of the waste heat in GoBiGas is an important element in the CO₂ balance.