Rhewum has been awarded the contract by Geldof N.V. to supply 3 screening machines for a leading Belgian energy supplier.
The screening machines type WA 220×538/1 including corresponding distributing feeders have been installed at Electrabel’s site in Nijmegen, Netherlands.
With a feed capacity of 120 m3/h (approx. 30 t/h) per each screen it has to be guaranteed that the crushed wood pellets will be separated from any oversize product. Such oversize grains would possibly lead to a clogging of the downstream processing units that blow the crushed wood pellets into conventional steam boilers.
The partial replacement of coal dust through crushed wood pellets as a source of emission allows to shift Co2 emissions of conventional energy sources to renewable ones.
This demanding screening application is realized by Rhewum WA screening machines with their highly efficient electro-magnetic drive system. The Rhewum electro-magnetic vibrating heads are the optimum solution for keeping the screen cloths free from any product cloggings and when applying fine resp. very fine screen cuts at high feed rates. The deciding factor for the screening is the high accelerations achieved by the magnetic drives. The inclination of the screening machine which classifies the feed product according to the projected mesh size further assists to prevent any cakings through wood fibers which themselves are being fluidised by means of the high-frequent oscillations. A flat standing screening machine (e.g. a Rhewum MDS screen) would not ensure a keeping-free of the screen cloths.
The crushed wood pellets flow at high speed over the screen cloths. Even at this high processing speed the screen installation length of 5,38 m in combination with the high frequency of the electro-magnetic drives ensure that each particle will frequently be in contact with the applied screen cloths for being screened out eventually.