Description
The sunliquid® process developed by Clariant meets all the requirements of a technically and economically efficient, innovative process for converting agricultural residues into climate-friendly advanced biofuel. Using process-integrated enzyme production, optimized enzymes, simultaneous conversion of cellulose and hemicellulose into ethanol and an energy-efficient process design, it has been possible to overcome technological challenges and sufficiently reduce production costs in order to arrive at a commercially viable basis. Renewable lignocellulosic resources, such as agricultural residues, do not compete with food and feed crops, but are created in sufficient quantities worldwide as a by-product of current agricultural practices, as in the case of straw from cereal production.
Since 2009, Clariant has been successfully operating a first pilot plant at its research facility in Munich. In July 2012, Germany´s largest plant to date started into operation in Straubing – a demonstration project with an annual capacity of up to 1,000 tons of ethanol.
Added value
- GHG savings of this second-generation ethanol are 95% compared to fossil fuels.
- Pre-treatment: Chemical-free pre-treatment lowers production and investment costs. At the same time, environmental, health and safety risks are minimized.
- The enzymes are highly optimized based on feedstock and process parameters, resulting in maximum yields and short reaction times under optimal conditions.
- Using optimized microorganisms, the sunliquid® process provides for efficient fermentation, giving rise to maximum ethanol yields. This highly-optimized, one-pot system simultaneously converts both C5 and C6 sugars to ethanol, delivering up to 50% more ethanol than conventional processes which convert only C6 sugars.
- The innovative and highly energy saving purification method reduces energy demand by up to 50% compared with conventional distillation. It is based on thorough process planning and energy integration, resulting in an entirely energy self-sufficient process.
- Finally, the sunliquid technology enables the use of lignocellulosic biomass, a 100% renewable feedstock found in wheat straw, corn stover and sugarcane bagasse that is available globally in large quantities.
- In addition to the application in the transport sector, the technology offers a platform for conversion of agricultural residues into a range of chemicals for different industries and applications.
Challenges
- Feedstocks with low indirect land use change impacts when used for biofuels are inadequately promoted for their contribution to the decarbonisation of the economy.
- Low levels of support to feedstocks for advanced biofuels, for which technology is more innovative and less mature.
- Targeted research and innovation programs, public-funding for research-oriented pilot plants and demonstration activities, and public support to minimize financial risks are lacking.
- Low market demand for bio-based products through tax reduction or bio-based product categories, deduction of bio-based carbon footprint in the calculation of the product’s total CO2 emissions, improved EU and international standards.
- Legal uncertainty.