Pyrolysis is the thermal decomposition of large molecules by heating in the absence of oxygen at more than 500 °C. One of the products of this process is pyrolysis oil. Unfortunately, current fast pyrolysis processes produce an oil that is not directly usable. The Carbon Trust Pyrolysis Challenge seeks to develop new means of producing better quality pyrolysis oil and upgrading the oil before or at the refinery.

Specific expected outcomes of the program include:

• Proof of scientific and engineering principle for a novel process for low-cost and low GHG intensity production and/or upgrading of biomass pyrolysis oil;

• Complete characterization of the upgraded oil, including details of processes and the impact of different feedstocks;

• An assessment of the likely commercial and environmental value of any associated co-products, and processes for their exploitation;

• Development of a large lab-scale or small industrial demonstration unit (capable of delivering cubic meters of refinery-grade pyrolysis oil) modeling of the full-scale process economics, whole system GHG intensity; and

• Key technical parameters (e.g. catalyst lifetime).

Carbon Trust analysis shows that the carbon footprint of this new pyrolysis biofuel could potentially achieve a carbon saving of 95% when compared to fossil fuels. This is a significantly higher carbon saving than some existing biofuels, which also do not currently factor in the impacts of land use change when calculating the carbon saving.

The consortium aims to produce its first biofuel from a pilot plant in 2014 and there is potential, using UK biomass alone, to scale production to more than 2 million tonnes per year. This will generate a saving of 7 million tonnes of carbon, which is the equivalent to the annual emissions of 3 million cars, according to the Carbon Trust. Waste can be cost-effectively pyrolyzed at a relatively small scale; in the future, the UK could have a network of mini pyrolysis ‘oil refineries’ at locations such as landfill sites, according to the Carbon Trust.

The UK Renewable Transport Fuel Obligation (RTFO) stipulates that forecourt gasoline and diesel already must include a 3.25% blend of biofuel and by 2020 an EU directive will see this figure rise to 10%. Pyrolysis not only potentially offers the lowest cost production route of any biofuel technology (between £0.30 and £0.48 per liter—US$1.72 to $2.76 per gallon US—of diesel biofuel), but could also meet more than half of the 2020 RTFO target, according to the company.

Alongside the Axion consortium, Carbon Trust is also announcing a £500,000 research grant for the University of York to conduct earlier-stage R&D into a process to use microwaves to pyrolyze waste. This offers greater energy efficiencies and could also provide very high quality oil which could lead to pure biofuel being used in cars.

The Carbon Trust is a not-for-profit company with the mission to accelerate the move to a low-carbon economy, providing specialist support to business and the public sector to help cut carbon emissions, save energy and commercialize low carbon technologies.