The efficient utilization of liquid manure and digestate poses growing challenges for farms and biogas plants. Especially in regions with high livestock densities and intensive arable farming, the pressure to manage excess nutrients in a targeted manner is increasing. The agricultural company Bösing has specialized in precisely this problem and uses its mobile decanter centrifuge to demonstrate how modern separation technology can help to optimize the use of digestate both economically and ecologically.
A farm near Osnabrück operates its own biogas plant in addition to keeping sows, rearing piglets and fattening pigs. The plant is mainly fed with NaWaRo and pig manure. Due to the pig manure, the fermentation substrates have a correspondingly high phosphorus content. Due to the P upper limits within the Fertilizer Ordinance, the fermentation substrate can only be applied to the farm's own arable land to a limited extent. The aim of the farm is to process the fermentation residues in such a way that the low-viscosity phase (filtrate) can be used specifically on its own land, while the phosphorus-rich solid matter is marketed.
Earlier trials with press screw separators from various manufacturers showed inadequate results. Although coarse fibers were removed, fines, suspended solids and, above all, phosphorus remained in the thin phase. The result: ineffective separation and hardly any benefit for the company. It would not have been economically viable for the company to purchase its own decanter centrifuge.
The mobile decanter centrifuge from the agricultural company Bösing solves the problem on several levels: It achieves significantly higher separation efficiencies, especially for phosphorus, and also separates the finest suspended solids and sand components. It is the ideal technology for pig manure and fermentation residues with a high nutrient density. The service solution eliminates high investment costs for the farm.
The decanter centrifuge is installed on a mobile trailer and can be used completely independently. The equipment includes
Thanks to the accompanying pump trolley, the raw slurry can be conveyed up to 80 meters to the centrifuge. Depending on the conditions, it only takes around 30 minutes to set up on site. Hygiene is also taken into account: The entire system is cleaned and disinfected after each use.
At the heart of the system is a high-performance centrifuge with a drum that rotates at up to 3600 rpm. An internal screw continuously transports the solids away. Separation takes place purely physically by centrifugal force, based on the different densities of the components - a clear advantage over the "squeezing out" of screw separators.
The raw substrate is sucked in via a cutting filter and a rotary lobe pump, passes through a flow meter and enters the centrifuge. The filtrate passes through a special slalom system to minimize foaming before being pumped into the final storage facility via fire hoses. The solids are deposited at the rear of the system by means of a swiveling screw.
The entire system can be operated via remote maintenance. The company's technicians adjust parameters such as speed or flow rate as required. With homogeneous slurry, the system runs for several days at a time. The farmer simply checks the surroundings and pushes the solid matter aside if necessary.
The decanter centrifuge is particularly suitable for pig manure, fermentation substrates and also cattle manure. The low-viscosity phase can be applied to cereals and grassland in spring and summer, while the solids are exported or used as humus fertilizer.
If the agitators fail or the dry matter content is too high, the centrifuge allows for a recirculation separation directly in the tank. Sand deposits at the bottom of elevated tanks can also be separated in a targeted manner - without interrupting ongoing operation.
In combination with a mobile polymer plant, sewage sludge, industrial sludge or pond sludge can also be dewatered. Flocculants are used to optimize the separation performance.
Many wastewater treatment plants or industrial plants use the mobile centrifuge temporarily to bridge maintenance or overhauls of their stationary systems - often for several weeks or months.
The mobile decanter centrifuge offers agricultural businesses an economically and ecologically sensible solution for slurry/digestate separation and sludge dewatering. It closes the gap between technical performance and economic efficiency. Particularly in nutrient surplus regions, it enables nutrients to be targeted to where they are needed - without unnecessary ballast. Whether in pig farming, on biogas plants or in industry/municipalities: anyone who wants to separate efficiently can hardly avoid this technology.
The company should be able to provide at least 500 m³ of raw substrate. All that is required is a standard slurry connection and a storage tank for the filtrate. Everything else - including hoses, hose bridges, pumps and power supply - is provided by the Bösing team.
The technology is used in agriculture (especially for pig and cattle manure), in biogas plants, in sewage treatment plants and for industrial and municipal sludge.
The main area of application is in Germany and the neighboring Netherlands. International assignments are also possible on request.
After each job, all parts of the plant are thoroughly cleaned and disinfected. We leave the site as we found it.
That depends on the volume - with homogeneous liquid manure, up to 1,000 m³ can be processed per day, almost continuously in automatic mode.
The solids contain high amounts of phosphorus and organic matter. They are therefore ideal for export to arable farming regions or as humus fertilizer.