A global filtration manufacturer approached MID to ask for assistance with a project involving the handling of domestic waste at a recycling facility in Wandsworth, London. As with most waste streams, problems in handling the material stem from the variance in material types, shapes and overall size and finding an ‘off the shelf’ valve that can reliably handle such a diverse range of materials is a difficult task.........
One of the largest and most successful filtration manufacturers in the world approached MID to assist with a major project involving the handling of shredded domestic waste at a material recycling facility in Wandsworth in London.
Consisting of a range of different materials from shredded paper and cardboard packaging to a variety of plastics in the form of food packaging, bottles and bottle tops, the waste was initially screened to eliminate oversized pieces or material that hadn’t shredded completely and then vacuumed to their cyclone filtration unit.
Choosing an ‘off the shelf’ rotary valve that could reliably cope with discharging such a wide range of materials with such differing sizes and shapes from the cyclone without repeatedly jamming, became a difficult task.
After consulting with MID, we recommended one of our Waste Handling Rotary Valves that had been designed specifically to handle material with such varying physical properties. The fundamental difference in design surrounds the rotor blades that are designed with flexible tips that when presented with oversized material ‘flex’ to allow the piece past the blade, and then spring back into position to maintain the rotor clearance with the valve body. With the valve body manufactured from ABRO steel, the carbon steel rotor was fitted with flexible spring steel tips that could bend enough to prevent the valve from jamming but could then spring back to their original position.
The dust generated from the shredding process was quite abrasive and would have created hours of future maintenance if we had employed the traditional gland packing method of sealing the shaft. Instead, we fitted our renowned mechanical shaft seals which require no maintenance at all and in most cases will outlast the normal operating life of the valve itself.
In addition to this the valve was supplied with ATEX Zone 22 certification.