New dry recycling process

Soil and building rubble processing with 3-fraction star screen, grizzly screen, impact crusher and air separation

T‌he combination consists of the starscreen 3-mta and a windsifter. It can be extended with an impact crusher. The 3-fraction starscreen has a fine and a coarse starscreen deck and a grizzly screen above the starscreen material hopper. First of all, the very coarse material is separated before it goes to coarse screening and is then finely screened. In the course of the material feed, the grizzly screen separates out oversized material components with rotating rollers; these coarse components (e.g. larger stones or wood components) fall off to the side of the starscreen. The fraction 0 – 150/300 mm passes between the individual rollers into the material hopper and is transferred from there to the coarse starscreen. The coarse screen separates at 63 mm (corresponds to a length of approx. 160 mm). The fraction 63 – 150/300 mm falls off before the starscreen. In this case it is taken over by an impact crusher and crushed.

From the fraction 0 – 63 mm the fine star screen deck then screens at 18 mm. The fine fraction (in this case soil) is discharged to the side in a large, easily removable windrow. The fraction 18 – 63 mm is transferred well cleaned to the windsifter bws 5.0, which transports the material to the side of the starscreen. During the transfer of material from the starscreen to the air classifier, iron is removed by a magnetic roller and collected in a container. The feeding belt from the air classifier conveys the fraction 18 – 63 mm over the blower nozzle. The light fractions are blown by the air classifier in the direction of flow. The wind flow can be adjusted to different strengths. The heavy fraction falls onto a conveyor belt and is discharged laterally by the air classifier.

After the first pass, the soil and fraction 18 – 63 mm can be recycled. Before the second pass, the space is cleared and the fractions > 150/300 mm and 63 – 150/300 mm are crushed and then returned to the star screen. In the second pass the fraction 0 – 18 mm consists of crushed mineral.

The wheel-mounted and track-mounted starscreen travels on site by means of a caterpillar to the pile. Displacement is possible quickly at any time. The air separation can be relocated by means of a wheel loader or excavator. The system can already be used for a working area of 400 – 500 m².


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