BOPET Crushed Film Recycling Line in Middle East

In the BOPET film recycling process, handling lightweight materials with a low bulk density of approximately 150Kg/m3 is a primary challenge.

BOPET crushed films are highly prone to bridging at the extruder feed throat, leading to starved feeding and directly restricting the continuous throughput. Furthermore, polyester (PET/BOPET) materials are highly susceptible to hydrolysis during high-temperature melt extrusion.

If volatiles and residual moisture are not efficiently extracted from the melt, the finished pellets are prone to void defects and face the risk of a drop in intrinsic viscosity (IV), thereby impairing their downstream reuse value.

To overcome the feeding bottlenecks of low-bulk-density materials, this solution features a flat-bottom silo and a vertical force feeder at the first open feeding barrel. An auxiliary agitation device, combined with the forced feeding screw, applies continuous mechanical thrust to the BOPET crushed films. This design significantly reduces the probability of material bridging and increases the filling degree in the screw channels, thereby sustaining a stable output of 600~900Kg/Hr.

To address BOPET’s susceptibility to hydrolysis, a dedicated vacuum exhaust chamber is equipped at the 5th barrel, integrated with a two-stage vacuum devolatilization system comprising a Roots pump and a screw pump. This system provides deep dehumidification and devolatilization capabilities during the melting phase, rapidly extracting residual moisture and low-molecular-weight volatiles from the polymer melt. This deep vacuum setup helps suppress high-temperature hydrolysis reactions, thereby reducing the risk of intrinsic viscosity (IV) loss in the recycled pellets.

For the melt filtration and pelletizing stages, the equipment utilizes a double-station dual-pillar screen changer and a water-cooled strand pelletizing system. The dual-pillar filter maintains controllable melt pressure fluctuations while intercepting unmelted impurities, reducing production interruptions during screen changes. Subsequently, the cold-pulling die head, paired with a stainless steel water tank, provides adequate cooling, and the pelletizer ensures uniform cutting, yielding finished granules with consistent visual appearance and bulk density.

During the full-load Factory Acceptance Test (FAT), the TDY110 production line operated steadily under the control of the Siemens S7-1500 PLC. Key processing metrics—such as stable main motor load, controllable melt pressure fluctuations, and temperature profiles remaining stable and in line with set requirements—all met engineering expectations.

Actual observations of the produced BOPET recycled pellets showed a uniform appearance without obvious void defects. The successful execution of this project provides a proven configuration reference for similar projects globally dealing with extremely low-bulk-density polyester scrap.