Funding Success: Biofuel made from straw

A model of Germany's largest pilot plant for biotechnological production of biofuel from straw. © Süd-Chemie AGFederal Minister Schavan was in Straubing, Bavaria to officially open an exciting plant on 20 July 2012. At first glance, the steel tubes and boilers appear like any other industrial plant, and the manufactured product Ethanol is nothing new either. But there are two distinctive characteristics: for one thing, straw serves as the raw material, and for another, the transformation occurs biologically with the help of enzymes and microorganisms. This Clariant pilot plant produces bioethanol from agricultural residue. 4500 tonnes of straw are to be refined into 1000 tonnes of bioethanol each year. The pilot plant is expected to show how this process can be implemented commercially and on a large scale.

In order to decrease both emissions of the greenhouse gas CO2 and reliance on petroleum imports, we need alternatives - and one of these is the use of biomass. Bioethanol can be used as biofuel, but it is also a basis for many other products, including polyethylene (PE) - a widely used synthetic material.

Bioethanol, however, is not entirely undisputed: the introduction of the new biofuel E10, which contains 10% ethanol produced through the fermentation of sugar beets or cereal crops, met with public scepticism and debate about the competition between biofuels and food supply needs. Researchers are looking for ways to produce biofuel with plants or plant parts that are not needed in the production of food and thereby avoid the 'food or fuel' dilemma. Whereas the first generation biofuels currently on the market only use specific plant parts such as rapeseed, maize or the sugar beet tuber, second generation biofuels still in development will use all plant parts, including those that are lignified and inedible. This can make use of the many million tonnes of agriculture residues like straw and sugar beet leaves produced every year, while reducing competition for food supply. There is no longer a need to choose between fuel and food - now both can be supplied from the same field without interfering with each other.

Süd-Chemie AG, which has been part of Clariant AG since 1 July 2012, is leading the way in research and development in the field of second generation biofuels. With funding from the BMBF, the company is building the as yet largest pilot plant in Germany for the production of ethanol from straw.

Süd-Chemie started small-scale production of climate-friendly second generation biofuel in 2009. The company's sunliquid technology, an innovative and sustainable process of cost-effective and energy-efficient production of bioethanol from agricultural residues or other lignocellulosic biomass, was tested at the company's pilot plant. The sunliquid process involves breaking down plant parts that contain cellulose - wheat or maize straw, for example - into sugars through enzymatic conversion. Ethanol is produced through fermentation - a process similar to that in beer brewing. In addition to cellulose, the sunliquid process can convert hemicellulose into ethanol and thereby increase yield by about 50%. The cellulosic ethanol produced in the sunliquid process can cut greenhouse gas emissions by up to 95% as compared to fossil fuels such as petroleum or natural gas.

After the successful completion of the test phase, the Munich-based firm began building the largest pilot plant to date for the production of cellulosic ethanol in July 2011. Total costs for the project are about 28 million euros, 16 million euros of which will be spent on the construction of the plant itself, while just under 12 million euros will go to accompanying research. Part of these costs are carried by the Federal Ministry of Education and Research and the Bavarian State Government who are each contributing 5 million euros.

Bioethanol is produced from straw and other agricultural residues. ©Süd-Chemie AGThe pilot plant represents the last necessary step towards the realization of industrial-scale production plants that will use the sunliquid process. The knowledge gained through research and development at the plant will serve as the basis for future industrial-scale biorefineries with maximum efficiency and optimal greenhouse gas savings. The Clariant facility is a first step on the way to a sustainable and climate-friendly transformation of the energy system in Germany. It will also act as an important driver of the structural change envisioned by the Federal Government in the National Research Strategy BioEconomy 2030 to move from an oil-based to a bio-based economy.