Industrial screens are used in the minerals processing industry to separate solids from liquids and to separate particulate materials into different size ranges. The Sweco separator is a screening device that vibrates about its centre of mass. Sweco claim greater capacity and screening efficiency with less blinding than other types of screening devices. However, technology invented and developed by Vibtec Engineering in Israel has demonstrated that the throughputs of Sweco screens can be increased by at least an order of magnitude (at mesh sizes less than 100 mum) for dry material, without sacrificing efficiency, by retrofitting a device called a Kroosher. The Kroosher is a mechanical converter, converting monoharmonic oscillations to amplified polyharmonic oscillations. Dry screening test work was conducted in order to identify and quantify changes in efficiency for the screening process. It was found that for the same screening efficiency, the throughput may be increased by more than 810% by fitting the Kroosher to a standard Sweco. (C) 2002 Elsevier Science Ltd. All rights reserved.