BW2Pro

Biowaste to Products

Topic

Within the framework of BW2Pro, a modular biorefinery for the utilization of municipal biowaste is set up and operated in a pilot scale with a throughput of 1 metric ton per day. On the basis of the biowaste, high-quality products are to be provided for material use on one hand and for energy generation on the other. A main challenge is the complex composition of the biowaste used, which is caused, for example, by seasonal influences.

Goals

The BW2Pro biorefinery will, therefore, be equipped with innovative technologies for the treatment of complex biowaste, which will make efficient recycling possible in the first place. These are a steam explosion (SE) and a high-load fermentation. In the SE, the biowaste is thermally treated under pressure and then abruptly depressurized. During this process, the cells in the biowaste burst open, allowing the cell fluids to escape while the fibers remain intact. A solid-liquid separation is executed afterwards. The solid phase is turned into plant pots or composite materials and thereby recycled. Biogas is exclusively obtained from the liquid phase and produced in a two-stage high-load digestion process. This means that hydrolysis and methanogenesis take place separately in a hydrolysis reactor and a methane reactor. The process can be operated very flexibly and is capable of efficiently utilizing the produced liquids by generation biogas on demand with high organic loading rates. The improved utilization of biowaste represents an important pillar for achieving a sustainable bioeconomy. 

Project tasks of the State Institute

The pilot biorefinery is currently being built on the site of the Rems-Murr district's waste fermentation plant and is scheduled to go into operation in June 2023. In addition, a lab-scale SE system and six fixed-bed digesters are being built as part of the project. Both are also scheduled to go into operation in June 2023.