Upcycling of brewers' spent grain liquid

Situation

Together with the Locher brewery, UpGrain AG has developed a process in which various products are obtained from brewers' spent grains. The proteins obtained by this have a lower greenhouse gas impact than plant proteins because the impact from primary production is eliminated. Individual products made from the recovered barley proteins and fibres are already commercially available. To ensure that the process is as sustainable as possible, the spent grains are dried mechanically as far as possible. This produces large quantities of press water. Its organic load is too high to be either discharged directly into the waste water treatment or to be fermented in a biogas plant. Press water treatment is therefore a crucial point in the entire process. At the same time, it is another side stream which could be utilised in a second step. The aim of this project is to develop a process for separating the solids from the press water to lower its organic load.