Optimisation and operational experience of the ‘Pilothof’ pilot plant for the treatment of milking parlour wastewater in Wipperfürth
How can heavily polluted wastewater from farms be treated reliably? This question is at the heart of research being carried out at a pilot plant that combines two near-natural treatment processes: a constructed wetland and a soil retention filter. The pilot plant at the Pilothof has been under development for optimisation purposes since 2025. The Research Institute for Water Management and Climate Future at RWTH Aachen University (FiW) e. V. is working closely with Wegerhof KG, the farm where the pilot plant is located, and the Wupperverband.
Through regular site visits and weekly sampling, the participants analyse the plant’s operation and are gradually implementing technical and operational optimisation measures. The aim is to identify existing challenges and systematically improve treatment performance under practical conditions.
Since 2025, the pilot plant at the Pilothof has been further developed to improve the treatment of agricultural wastewater under real-world conditions. Analyses of the wastewater streams show that one particular stream, originating from the cleaning of the milking system, contains high levels of milk and milk fat and places an excessive load on the plant. A system control mechanism originally planned to operate based on electrical conductivity and pH proved to be insufficient, so the individual sub-streams were examined in great detail. This identified a small but particularly heavily polluted wastewater stream with high levels of milk and fat residues. In the future, separate treatment of this sub-stream is expected to significantly improve the plant’s cleaning performance.
Treatment performance has already been improved through structural and operational adjustments. These include stabilising the pH value in the retention bed filter, optimised water distribution and improved oxygen supply to the filter media. At the same time, plant operation has been stabilised through adjustments to the batch feeders and the replacement of pumps. Challenges remain in the form of sludge and grease deposits in the pre-treatment tank and the constructed wetland itself, as well as in the continuous monitoring of the plant. Here, automated remote monitoring offers potential for further improvements to operations in the future.
The project is made possible by LANUK.
