Biologists offer distilleries a leaner, cleaner solution

Biologists in Manchester have helped create a breakthrough in alcohol production that could save industry millions of pounds and help clean up the environment.

Many distilleries across Europe still rely on 19th century technology pioneered by Louis Pasteur, so the invention of a vastly more efficient fermenting system offers exciting possibilities.

The technology, developed at Manchester Metropolitan University (MMU), also allows continuous production of the chemical, an improvement from the current process whereby ethanol (or ethyl alcohol) is produced in batches.

MMU, TTZ in Germany, INETI and the University of Coimbra in Portugal will develop the system, which will be commercialised and used by a consortium of six companies from the UK, Spain, Portugal and Germany. The £640,000 project is backed by a £320,000 grant from the European Union.

Dr Mike Dempsey, whose research on adhesive organisms and fluidised bed fermentation is central to the technique, said: “The new process involves the way organisms are used in the fermenter. By using fluidised beds we can increase cell concentration tenfold with a similar increase in the rate of production. Coupled with continuous fermentation, this should raise ethyl alcohol productivity at least 20 fold.

The development has implications for both commercial and environmental costs. This is because the process will use agricultural and food industry waste as a source of sugar, and the product ethanol can be used as a motor fuel or fuel-extender. Not only will any pollution (ie in rivers as effluent) by the original wastes be eliminated but also that caused by toxic fuel-extenders, such as MBTE.

The use of ethanol as a fuel will not make a net contribution to emissions of carbon dioxide (CO2, a greenhouse gas), because the crops from which the wastes come took it in during photosynthesis. This is what Dr Dempsey calls the “fuel ethanol diamond”; where CO2 take up by plants from air is converted to sugars, which are fermented to ethanol and end up back in the air when it is burnt.

MMU will receive £60,000, including a new post-doctoral researcher, to carry out research in the selection of microbes and in screening for adhesive, ethanol-producing strains suitable for the fluidised bed process.