Bioplastic from sewage

Bioplastic from sewage

Sewage and industrial wastewater often contain many valuable substances that can be used as raw materials for biobased products. However, this potential is currently not or hardly exploited, resulting in the loss of valuable materials. In the INTERREG NWE project WOW! for sewage, it is examined whether sustainable value chains for these valuable substances can be developed. One of the value chains being investigated is the production of PHA (polyhydroxyalkanoates), a fully biodegradable bioplastic.

PHA can be produced by bacteria that are often already present in the secondary sludge of sewage treatment plants. Under the right conditions, these bacteria can convert fatty acids into PHA. The PHA is then stored in the bacterial cell as a reserve substance. The fatty acids needed for the accumulation of PHA may already be present in sewage or may be produced by partially fermenting the primary sludge of the sewage treatment plant.

Researchers of the Dutch Centre of Expertise Biobased Economy (CoEBBE) of Avans University of Applied Sciences, in collaboration with the University of Kaiserslautern and Wupperverbandsgesellschaft für integrale Wasserwirtschaft, are currently working on the improvement of the efficiency and stabilisation of this PHA production process. In the second half of 2020,  the extraction of PHA will be tested on a pilot scale . The intention is to produce 10 – 20 kg PHA.

(Innovative Materials 2020 volume 3)