(Photo: LFV/Tommy Säfström)
Mon 18 Jan 2010 – A major study to investigate the technical and financial feasibility of a biorefinery plant to supply Stockholm’s Arlanda Airport with 50,000 tonnes of jet biofuel per year has been completed. The project was initiated and part-financed by LFV, which operates Sweden’s airports and air navigation service, and has substantial carbon reduction targets to meet. LFV claims the biorefinery would make the airport truly carbon neutral. With the added production of other hydrocarbons and district heating, this could reduce total CO2 emissions at the airport by 150,000 tonnes per year with a 10 percent blend of jet biofuels. The biomass for the facility would come from forestry chips and other wood residues. The report says the prospects were “very promising, showing high efficiency and competitive production costs.”
The extensive and detailed project, led by Nykomb Synergetics, is amongst the first to study biomass gasification and jet biofuel production.
After investigating a number of possible sites, two locations of the plant were studied, each with different plant configurations and total capacities. The first, at Brista, just south of Arlanda, was chosen as a potential site for full production of jet biofuel. The other plant, south of Stockholm at Igelsta, would produce an intermediate Fischer-Tropsch (FT) synthetic oil product to be further refined and upgraded at another refinery to several different fuels as well as jet fuel.
The total investment costs have been calculated at around $726 million for Brista and $1,063 million for Igelsta, which the project group agrees were “rather steep” but says there was room for reductions.
The report says its calculated production costs at Brista were not competitive with conventional jet fuel at a current crude oil price of $67 per barrel. However, with the cost of crude forecasted to rise to $100 and the impact of the EU Emissions Trading Scheme in 2012, this would change. On the other hand, an intermediate FT product for further upgrade would be competitive already at today’s prices and costs. Costs can also be offset by revenues from other by-products such as heating, naphtha and heavy diesel.
Arlanda is the only airport in the world with a CO2 emissions cap in its environmental permit. This means that emissions from aircraft take-offs and landings (the LTO cycle), road traffic to and from the airport, internal vehicle traffic and the heating and cooling of buildings and terminals may be no higher in 2011 than they were in 1990. LFV must therefore minimize overall CO2 emissions from airborne as well as ground-based operations, and at the same time face up to the challenge of how to expand traffic operations at Arlanda over the coming years.
The LTO cycle accounts for around 10% of all fuel filled at Arlanda. With a 10% jet biofuel blend, there would be an estimated reduction of 150,000 tonnes of CO2 per year, depending on the CO2 efficiency of the fuel production, hence the annual requirement for 50,000 tonnes of jet biofuel (1 tonne of fuel emits 3.15 tonnes of CO2).
The main technical objectives of the plant are to be biomass-based with fluidized bed gasification technology integrated with a physical gas cleaning and conditioning process and a slurry-based synthesis plant, where the steam and power needs have been balanced with a biomass boiler plant. The project group has chosen “a simple and robust design to ensure competitive investment cost, high plant availability and reliability. Except for the biomass gasification technology, which has not been demonstrated at large scale for synthesis gas production, only proven and commercially available technology has been incorporated in the chosen plant configuration.”
The group had to consider fuel logistics, nearby heating networks, outdoor biomass storage capacity and other specific needs when locating a site, as well as easy integration with the current regular jet fuel supply and storage operations at Arlanda.
Although no CO2 life-cycle analysis was undertaken, the report says the overall environmental effects of using cleaner FT fuel are positive, with added reductions in emissions of sulphurs, aromatics and particles. The project group believes FT-based biofuel is the only alternative for technically viable commercial aviation fuel that complies with the ASTM D1655 (US) and DefStan 91-91 (UK) specifications.
It also accepts that the biomass is still a developing market in terms of price. In contrast to oil, biomass is also very voluminous and transport costs high. “For the purpose of FT production in Sweden, forest industry residuals would naturally be the biomass source and a versatile, efficient transport network must be considered when planning a FT plant,” it adds.
The study concludes that detailed feasibility work should be continued, with supplier contacts established alongside further technical optimization.
Copyright © 2014 GreenAir Communications