Process Low-Bulk-Density Film More Reliably

Evaluate a PreDensifier when lightweight film, fibres or nonwovens need controlled densification and stable feeding into MAS extrusion without process-water injection in the densification/extrusion stage. A cutter-compactor may remain suitable when intensive agglomeration or another preparation behaviour is preferred. The choice should be based on representative material, feeding behaviour, temperature sensitivity, throughput and target output.

It may not be the right route when the input needs wet washing, a different size-reduction concept, intensive agglomeration or another preparation method outside the PreDensifier operating scope. It may also be unnecessary when the material already feeds consistently and the required output can be achieved with a simpler line. MAS should compare alternatives before recommending the equipment.

Potential materials include LDPE and LLDPE film, PP woven material, selected fibres, nonwovens, fleece, XPS and post-consumer or post-industrial film streams. Suitability depends on polymer, particle form, bulk density, moisture, contamination, additives and feeding behaviour. The published list should be treated as materials to evaluate, not a guarantee for every stream.

The PreDensifier and MAS extrusion concept is described as operating without process-water injection. This does not mean every complete recycling line is waterless. Depending on contamination and moisture, the material may still need upstream dry cleaning, wet washing or another preparation step.

Throughput depends on film type, polymer, bulk density, moisture, contamination, particle size, feeding stability, extrusion conditions, filtration load and target pellet quality. Do not plan from a theoretical maximum alone. Use representative material data and, where necessary, a trial to establish a realistic operating range.

The system adds preparation equipment, control requirements and investment that may not be justified for simple, stable feedstocks. Performance still depends on correct shredding, contamination control, filtration, operating settings and maintenance. Some inputs may need upstream washing or another preparation technology. These requirements should be compared with cutter-compactor and other routes.

Cost depends on input preparation, machine size, extrusion capacity, filtration and pelletising scope, automation, utilities, installation, testing and service requirements. Material condition, target throughput and required output quality determine the final configuration, so a meaningful quotation requires project-specific data.

Compare energy in kWh/kg under the same material, moisture, throughput, output and system-boundary conditions. Include upstream preparation, extrusion, filtration, pelletising and relevant utilities. Do not use “more energy efficient” or similar comparative claims without a stated benchmark and approved test evidence.

Test representative material for polymer, film form, bulk density, moisture, contamination, particle size and feeding behaviour. During the trial, record feed stability, throughput, temperature, pressure, vacuum, energy, filtration behaviour and downtime. Verify pellet consistency, moisture, contamination and the agreed application-specific properties.

Yes, additional filtration, compounding or line components can be evaluated when a defined bottleneck or new product requirement justifies them. Confirm the integration scope, downtime, utilities, expected performance and economics before selecting an upgrade.

Compare feasible preparation routes using realistic throughput, energy, yield, rejects, labour, cleaning time, downtime, maintenance, wear parts and the value of the final product. State all assumptions, material conditions, comparison period and product values clearly.