Sorting Systems

You can separate the material by size using a trommel screen or screen drum as well as one of our disc screens or the star screen. Depending on the size, the material falls through the screen openings or is passed on to the end of the drum or trommel. With star screens, the finer fraction falls into the openings between the screen stars, while the coarse fraction is transported backwards on the screen deck by the rotating movement. We offer our BRT HARTNER SD screen drum and ST trommel screen as well as our STS star screen for this purpose. The BRT HARTNER SC and SF disc screens work in a similar way to the star screen.

In the disc as well as the star screens the coarse material is passed "smoothly" over the screen deck. This is done by means of rotating oval disks or screening stars with screening fingers, which push the material forward. The fine material falls through between the disks and screen stars. Star screens such as the STS are particularly suitable for very fine material such as compost or soil, but they are not suitable for material with risk of entanglement. Disc screens such as the SC or SF, on the other hand, are also perfect for throughputs such as paper, cardboard and cardboard packaging.

Technically, we differentiate between screen drums and trommel screens with regard to the material transfer within the drum. A trommel screen stands horizontally and the material is conveyed to the outlet by a screw or spiral as the trommel rotates and the material is thrown inside the trommel. A screen drum, on the other hand, has a pre defined incline and the material therefore automatically falls further and further forward as it is thrown up. A trommel screen can therefore be integrated into the process without a gradient, while the screening drum has a modular design. As it does not have a spiral, individual screening elements can be replaced at any time. This enables flexible adjustment of the screen section, so that the screen drum has three sections with different hole sizes, for example. With both screen types, the drum or trommel itself can of course also be replaced with another that has a different screen cut.
With our BRT HARTNER SD and ST, completely different grain sizes are possible.

You can sort by weight using an air belt separator or wind sifter. The material is usually blown under and the whirled up light fraction is sucked off from above. Air separation is often carried out on the discharge belts of sorting machines or in drop chutes. In the chute, the heavy fraction then falls down automatically by gravity.
You can also use a curved belt separator for certain materials. The material is propelled at high speed against a curved belt in order to utilize the different ballistic properties associated with its own weight. Heavy components are deflected downwards by the force of the impact, while lighter particles are whirled up and fly over the curved belt. In our BRT HARTNER BBS air belt separator, but also in the CO₂MPOST CLEANER, the use of wind sifting and curved belt is combined.

If you want to separate material into a 2D and a 3D fraction, you can take advantage of the different climbing ability and the uneven ballistic behavior of the components. Ballistic separators work by means of both vertical and horizontal conveying movements. Rolling, dimensionally stable bodies like stones, bottles and other hollow bodies follow the ballistic principle and are discharged towards the lower side of the machine. Flat materials like films, textiles or paper move to the overflow. They are thrown up several times and, when they hit the paddles, are freed as far as possible from any adhesions such as fine dirt or dust. A further fraction is separated by the screen perforation on the paddles. The size of the screen perforation can be freely selected. Ballistic separators can therefore produce a total of three fractions in just one pass. Depending on the type of waste, the BRT HARTNER BS ballistic separator is available as BSH, BSW or BSV. In addition, with the BRT HARTNER BPS we also have a ballistic separator especially for the separation of paper, cardboard and cardboard packaging.