Biffa Polymers, the world’s first food grade high density polyethylene (HDPE) bottle recycling plant, based at the Wilton International Petrochemical Complex in Redcar, UK, has installed a new swan neck conveyor, designed and manufactured by recycling engineering specialists Middleton Engineering.
Operating 24/7 as part of Biffa Polymers’ milk bottle processing line for post-consumer plastics, the new conveyor is designed to feed material at up to 2 metric tons per hour or 50 metric tons per day, transporting it from a high-speed electronic sorting unit that removes non-compliant material, to leave a clean HDPE waste stream, then up into the granulator. Chopped HDPE is then heated, extruded and cut into pellets and sold on for blow moulding new dairy bottles and other commodities.
The new conveyor was required following modifications to the granulator. It has been designed by Middleton to provide a consistent feed of material, to minimize previous spillage issues between the conveyor and the granulator and overcome overloading and jamming at the foot of the conveyor.
Middletons undertook a series of product trials at its manufacturing center in Somerset using scrap HDPE bottles to determine the optimal design for the conveyor, including the size of vertical rubber flights to deliver material to the granulator at the right speed and volume to keep the line working at maximum efficiency. Ease of access for scheduled cleaning and maintenance were also important design considerations for Biffa to allow debris to be removed and preventative maintenance to be carried out at required weekly intervals.
Middleton Engineering has also been awarded a further contract to design and supply a second conveyor to form part of a new milk bottle bale breaking system at Biffa Polymers. Bales of plastic bottles arriving at the plant will then be broken open by the machine and transported through an opening into the building on the new belt conveyor, which rises from the floor at an angle of 31 degrees to feed downstream processing.
With an overall length of 10.5m the conveyor includes a fully adjustable safety rope pull system, an automatic chain lubricator, soft start to minimize wear and speed controls to optimize flow rates. The exterior section of the conveyor is covered.
Earlier this year Middleton helped Island Waste, Guernsey’s largest independent waste recycling business, diverting 100 percent of the island’s waste from landfills after installing a twin ram baler and conveyor.