BHS-Sonthofen supplies the largest indexing belt filter in the company’s history

BHS-Sonthofen has received the order from an American customer to supply an indexing belt filter for extracting reusable substances from plant waste. With a filter area of almost 90 m², the type BF 350-255 filter plant is not only the largest plant that BHS has ever built, but it is also one of the most efficient of its kind in the world.

Advertisement

The indexing belt filter of type BF 350-255 will process up to 5,000 kg of fibrous plant waste hourly, extracting recoverable liquid components generated in a previous production process. The filtrate is used for the manufacture of basic chemicals, while the remaining solids, which could not previously be used, are reprocessed.

During project planning, the customer had initially envisaged a multi-stage process with a sequence of consecutive screening and filtration steps and with the solids being resuspended several times. The proposal from BHS-Sonthofen to use an indexing belt filter of type BF with a single process step convinced the customer, however. Not only is the process much simpler, but it also concentrates the reusable substances to a greater extent. This means that less energy is required for extracting the substances at a later stage in the process.

As part of the treatment process, the plant waste is first suspended in water. To ensure that the reusable substances dissolved in this can be extracted as effectively from the solid as possible, BHS implements a multistage counter-current wash process in the filter plant. This allows the filter to achieve a very good washout quality, thereby significantly increasing the concentration of the dissolved reusable product in the liquid. The BHS indexing belt filter of type BF 350-255 extracts approximately 10 percent more recoverable materials than conventional procedures.

Moreover, the operating costs are lower because the indexing belt filter requires about 30 percent less water than the multistage process. This also results in considerably lower investment costs as no multiple cascades of stirring tanks and filters are required. As the entire filter plant is much simpler in design than conventional plants, it ensures a high operational reliability. At the same time, maintenance costs are significantly lower in comparison to conventional plants.

After receiving the order in December 2015, BHS supplied the filter plant in spring 2016. Commissioning is planned for autumn 2016.