Biogas plant heats greenhouses and closes nutrient cycle

Client: Steimbker Biogas GmbH & Co. KG
Location: 31634 Steimbke

Challenge

Steimbker Biogas GmbH & Co KG generates electricity and heat in its biogas plant. The waste heat from the combined heat and power plants is used, among other things, to heat the greenhouses of a neighbouring nursery, while the fermentation residues are used as fertiliser on the fields. Whereas silage from maize and other energy crops as well as separated cattle manure had previously been the main energy sources, the biogas plant now had to be converted to utilise residues such as manure in order to comply with the 30 per cent maize cap required by law from 2026 onwards.

Solution

Brandt GmbH planned and implemented the entire feeding technology. Brandt installed the LEF 90 – a solids feeder that can hold 90 m³ of manure. The container is made of stainless steel to withstand corrosion over time. The screw conveyor in the LEF container transports the fibrous residue to the MaCBox, a proprietary development from Brandt: The substrate is already shredded in the MaCBox (=Mix and Cut in a Box), mixed with liquid and fed efficiently and evenly into the fermenter as a homogeneous suspension via the pipe system. Instead of mixing and fermenting the solid substrate exclusively in the fermenter, this step is carried out much more energy-efficiently by the MaCBox: This halves the stirring times in the fermenter and reduces electricity consumption. The fermentation residues produced during biogas production are not a waste product, but are used as agricultural fertiliser in neighbouring vegetable cultivation, closing the nutrient cycle.

Since the entire insertion technology was configured with standard components such as Brandt's LEF and MaCBox and optimally coordinated, the conversion could be implemented cost-effectively.

The Steimbke biogas plant is therefore already equipped to meet future legal requirements. It operates more economically and continues to supply the nursery with energy and the agricultural sector with nutrient-rich fertiliser. A future-oriented example of how renewable energy production and the circular economy go hand in hand!