The ideal combination
Therefore we studied different processing methods very closely with regard to output quality and operating costs. In tests of high and low-speed shredders, throughput and energy consumption were measured, and the granular size composition was determined by screening. To evaluate operating costs, the company compared single-stage processing with high and low-speed shredders, and two-stage processing with a combination of low-speed shredder and screener to return overlengths.
The two-stage version with screener returning overlengths turned out to be the most economical setup, taking due account of various conditions.
Effective and economical: Crambo and Multistar One
In these tests, biomass and waste wood processing was most effective when a Multistar One star screen was used. Shredding is done by an upstream Crambo. The Multistar One then separates out a defined useful fraction and returns the overlengths to the shredder. With a feed hopper for precise material transfer to the generously dimensioned screen deck, a discharge conveyor with four metre discharge height and a return conveyor that can pivot through 220°, the Multistar One provides a throughput of up to 200 cubic metres per hour.
The current for the electric motors can come either directly from the grid or from a combination of additional hydraulic pump on the shredder and hydraulic generator on the star screen. With its compact crane lift frame and variable conveyors for flexible setup, plus electric drive, the Multistar One is a very efficient as well as economical star screen.
The drive train of the Crambo direct shredder combines the functionality of hydraulic drive with the efficiency of mechanical drive. That means top economy while retaining all benefits like overload protection, reversibility and adaptation to the material. Two 2.8 m counterrotating toothed drums in the extra-large shredding chamber ensure positive feed. The degree of shredding can be adjusted flexibly, either by changing the screen basket, or even more conveniently by changing the entire screen basket cartridge. The shredder is quickly ready for the next Job.