New enzyme technology converts waste oils into biodiesel
Novozymes’ latest offering secures flexible feedstock selection and lower operational costs for biodiesel producers.
Today, Novozymes announced the launch of Novozymes Eversa®, the first commercially available enzymatic solution to make biodiesel from waste oils. The enzymatic process converts used cooking oil or other lower grade oils into biodiesel. Biodiesel producers can thereby reduce their raw material costs. The resulting biodiesel is sold to the same trade specification as biodiesel created through traditional chemical processing.
A solution that loves free fatty acids
Growing demand for vegetable oil in the food industry has resulted in increased prices, causing biodiesel producers to search for alternative – and more sustainable – feedstocks. Most of the oils currently used are sourced from soybeans, palm or rapeseed, and typically contain less than 0.5% free fatty acids (FFA). Existing biodiesel process designs have difficulty handling oils containing more than 0.5% FFA, meaning that waste oils with high FFAs have not been a viable feedstock option until now.
“The idea of enzymatic biodiesel is not new, but the costs involved have been too high for commercial viability,” says Frederik Mejlby, marketing director for Novozymes’ Grain Processing division. “Eversa changes this and enables biodiesel producers to finally work with waste oils and enjoy feedstock flexibility to avoid the pinch of volatile pricing.”
Eversa can work with a broad range of fatty materials as feedstock, but initial focus has been on used cooking oil, DDGS corn oil and fatty acid distillates.
Better process economy
Making the change from a chemical catalyst to the enzymatic process requires retrofitting in existing plants. Biodiesel producers looking to utilize Eversa will therefore have to invest time and resources to make the switch to the enzymatic process. Novozymes’ engineering partners estimate that the resulting improved process economy indicates a payback time of three years or less, depending on the plant setup and feedstock savings potential in that region.
“The enzymatic process uses less energy, and the cost of waste oil as a feedstock is significantly lower than refined oils,” says Frederik Mejlby. “A small number of plants have been producing biodiesel from waste oils using existing technologies. But this has not been cost-efficient until now, broadly speaking, as the waste oils have had to be refined before being processed using chemicals. We hope that our technology can unleash more of the potential in these lower grade feedstocks.”
Safer and more sustainable
The enzymatic process eliminates the need for sodium methoxide, one of the most hazardous chemicals in traditional biodiesel plants. The radical reduction of harsh chemicals and by-products ensures safety for both personnel and the environment.
“Switching to Eversa can lead to a safer working environment for plant operators. The enzymatic process does not use high pressure or high temperature,” says Frederik Mejlby. “And when it comes to the actual enzymes, their organic nature and mild process conditions do not generate toxic components as in some chemical biodiesel processes.”