Bacteria possible key to produce useful bioplastics from the gasification of urban waste
Each year, the European Union produces three billion tonnes of waste. According to Eurostat (the statistical office of the European Union), this equates to six tonnes of solid waste for every EU citizen. A major challenge is finding ways to reduce and reuse a large amount of this waste. But now, the EU funded Synpol Project, which aims to propel the sustainable production of new biopolymers from feedstock, has discovered ways to use bacteria for fermenting gases that can be used to produce bioplastics.
The project team has found that mixtures of bacterial species may enhance efficiencies of conversion. Such bioplastic compounds might have multiple applications, such as medical prosthetics to packaging applications.
Complex waste raw materials, such as municipal and chemical waste, contain a lot of reusable carbon that bacteria can digest and transform into biopolymers, which is the starting point for the project.
Three-step process shows promise
Following compression, the waste is pyrolysed before being gasified to produce syngas (synthesized fuel gas). This is a fuel gas mixture consisting primarily of hydrogen, carbon monoxide, and very often some carbon dioxide.
“The crucial questions are whether the high-energy inputs of gasification of biomass wastes are suitable and if the gasification process will technically work for the target feedstocks,” says Achim Raschka, head of technology and markets, Bio-based Chemistry & Industrial Biotechnology, Nova Institute (a private biotech and chemistry research center in Cologne, Germany). “These questions will be addressed by an economic and ecological analysis of the whole process in the project.”
It is still early days for the bioplastics sector. “Now, we are a very small industry, we have to grow,” says Krysty- Barbara Lange, spokesperson for the European Bioplastics Association in Berlin, Germany. Nowadays, food crops are the main source for first generation biopolymers. Second generation biopolymers are derived from other biomass resources such as wood or other plants. “We just grow a 0.01% of the global agriculture industry, but we need more options, and the Synpol project sounds very promising as a driver for a third generation of biopolymers.” But there are still significant challenges ahead to make this approach economically feasible and environmentally sustainable she thinks.
If the project platform delivers on efficiency, the biopolymer’s sector will take a significant step forward.
“[The compounds] will be a 100 percent biodegradable,” says Oliver Drzyzga, who is project manager, Synpol. He concludes: “now, we are working with [only] some grams of waste, but the aim is to make it economically sustainable, and build a big facility in Murcia [Spain].”