Recover residual materials from the brewing process
For most breweries, brewing grains are just what is left over after brewing and are often simply used as animal feed. In some cases, breweries even have to pay for their disposal, but a lot more lurks in these waste materials from the brewing process.
A project team jointly led by Steinecker and the two development specialists, Prof. Waldemar Reule and Dr. Rainer Gottschalk, is now demonstrating how these materials can be handled.
One of Brewnomic’s latest modules is a solution for recycling residual materials from the brewing process and using them for energy recovery. The solution is tested and optimized in a pilot plant as part of a Steinecker development project.
While the Brewnomic has so far only focused on using waste materials for energy recovery, the project team has now developed a material recovery process. This process consists of three steps:
- First, proteins are extracted from residual materials. This is done in a three-vessel system, similar to the concept of the CombiCube brewhouse. After dispersion and hydrolysis, the proteins are separated by membrane filtration.
- In the second step, the remaining biomass is acidified. Then the mineral fertilizer is obtained by means of an ion exchanger.
- This is followed by energy recovery in the form of biogas production. The wastewater from the brewery is also added and purified there.
Thanks to trends towards a sustainable, healthy and vegan lifestyle, the demand for plant-based protein sources is increasing in the manufacturing industry. Potential buyers of this highly sought-after raw material are not only dairies and food factories, but also producers of food supplements and the cosmetics industry. In addition, the sale of mineral fertilizer and the savings made by feeding biogas also pay off for the brewery. Thus, the sum of the annual revenues results in a return on investment (ROI) of only a few years, significantly lower than that of a conventional biogas installation where spent grains are only used for energy recovery.
The Ustersbacher Brauerei in Bavaria will be the first to use the concept developed for the recycling of spent grains in the reality of the workshop.
“Over the past 10 years, we have already implemented a number of measures. With each of them, we have taken one step at a time towards achieving our goal of becoming an energy self-sufficient brewery using the Brewnomic concept. It is therefore logical that our goal now is also to use the residual materials from the brewing process in the most sustainable way possible,” explained owner and manager of the brewery, Stephanie Schmid.