MAS introduces filter designed to extract contaminants from plastic scrap

Filter can be replaced in less than one hour using conventional tools, company says.

September 27, 2013
Recycling Today Staff
Equipment & Products Legislation & Regulations

The Austrian company Maschinen- und Anlagenbau Schulz (MAS) has introduced a continuous melt filter that has been designed to eliminate a range of contaminants typically found in processing plastic scrap.

The company says conventional filter systems using mesh screens are usually unable to manage even small amounts of impurities. However, MAS’ patented Continuous Disk Filter (CDF) system has as its central component a filtration disk rotating in the incoming flow of melt. The disk is made of tempered steel and has a pattern of fine perforations. According to the company, the filter is highly efficient at holding back impurities from the melt that it lets through.

The filter is available in four sizes. The basic modules have disk diameters of 300 or 510 millimeters (mm) and, depending on the type, either one or two fitted filter disks. The newly introduced and largest system, the CDF 500-D, is designed with two filter units in parallel, which have a diameter of 510 mm. The available active filter area is 3,650 square centimeters, which allows a melt throughput of between 1,300-2,000 kilograms per hour. MAS says the twin configuration makes it possible to keep the dimensions compact, ensuring that the filter is easy and flexible to handle, both during cleaning and maintenance and during transfers between a number of different extrusion lines when required.

To ensure the disk filter does not clog up in continuous operation, a scraper removes the contamination from the surface of the rotating screen disc, which is discharged continuously from the CDF, while the filtrated melt is forwarded to the pelletizing system.

Despite the considerably larger dimensions and masses of its components, the CDF 500-D filtration unit is as easy to maintain as smaller models of the same type because of its split housing, hinged connections and integrated service crane, the company says. The filter screen can be replaced in about 45 minutes using conventional tools and can be reused numerous times.

More information about the continuous melt filtration and the CDF 500-D from MAS is available from eFactor3 LLC in North America at 1-877-801-3232, or at