Fermentation plant and waste disposal centre Großefehn

Since the 1980s, MKW GmbH & Co KG has been operating a composting plant at the Großefehn waste disposal centre. Over the course of time, this has been modified again and again and at the start of the project consisted of 15 closed rotting tunnels. The challenge for us here was to expand the capacities, modernise the process and exploit the energy potential of the biogas.

By building a dry fermentation plant, we succeeded in increasing the total capacity of the plant by more than 15,000 Mg/a. It is based on plug flow fermentation in a partial flow process. For this purpose, the open biofilter plant had to be removed and replaced by a closed one elsewhere. A new hall with a feed bunker, crane system, feed doser, dewatering technology and conditioning boxes was built on the freed-up space. Next to it, the fermenter, the liquid fertiliser storage tank and two combined heat and power units were set up. With the help of a gas pipeline to the neighbouring MBWT*, the biogas can now be used either in the combined heat and power plants or fed to the RTO**. In addition, we designed a new pre-treatment technology and the associated conveyor technology and optimised the fine treatment.

Project data

• Increase in total capacity from 43,000 Mg/a to 60,000 Mg/a
• Fermentation capacity of 20,000 Mg/a
• Replacement of the open biofilter system by a closed one
• Pre-processing with shredder, star screen, two VU separators and conveyor belts
• Fine processing with two tension wave screens, two air classifiers, heavy material separator and

        conveyor belts

• Conveyor technology with crane system, feed dosing unit, screw conveyors, conveyor belts, tamping screw conveyor
• Dry fermentation by means of plug flow fermenter
• Dewatering by means of screw presses
• Biogas utilisation in two combined heat and power plants as well as in the RTO** of the neighbouring MBWT plant*
• Liquid fertiliser storage

Services

1.     Basic evaluation
2.     Preliminary planning
3.     Design planning
4.     Coordination of the experts for building ground, noise, odour and fire protection
5.     Integration of architectural services for building design
6.     Preparation for the awarding of contracts
7.     Participation in the awarding of contracts
8.     Accompaniment of the approval and works planning of the GC**
9.     Site management 

* Mechanical-biological waste treatment plant
** Regenerative thermal oxidation plant
*** General contractor