A PP/PE film washing line should be configured around the feedstock and downstream product, not a standard equipment list. Film source, polymer mix, soil, labels, moisture, printing and required output determine the opening, sorting, cutting, washing, separation, drying and water-treatment stages. Capacity and cost become meaningful only after those assumptions are written into the quotation.
Start with the material and saleable product
Post-commercial stretch wrap, mixed packaging film, agricultural film and woven PP bags impose different loads on a line. Record bale density, loose material characteristics, polymer composition, dirt, moisture, metals, paper, organics and seasonal variation. Then define whether the downstream process needs clean flakes, squeezed agglomerate or material prepared for pelletizing.
If the feedstock mix is not yet understood, first review PE film types and their washing requirements. The product specification should state the test methods and sampling point for contamination, moisture, particle form and any polymer-separation requirement.
Typical process modules and when they are needed
| Modulo | Scopo | Selection questions |
|---|---|---|
| Bale opening and controlled feeding | Loosens compacted film and stabilizes the load to downstream machines. | Bale form, bulk density, manual sorting needs and foreign-object risk. |
| Pre-sorting and metal control | Removes incompatible material before it damages equipment or contaminates output. | Polymer mix, metals, rigid plastics, paper and hazardous items. |
| Shredding or crushing | Creates a manageable size for washing and separation. | Film toughness, wrapping tendency, dirt, desired size and wet-versus-dry operation. |
| Prewash and friction washing | Releases loose soil, labels, residues and surface contamination. | Contamination type, wash intensity, water quality and wear. |
| Separazione galleggiante-affondante | Separates floating PP/PE from many dense contaminants. | Film form, tank residence, skimming and bottom-discharge load. |
| Risciacquo | Removes released contamination and, where used, wash chemistry. | Output requirement, water cascade and carry-over control. |
| Mechanical dewatering and squeezing | Removes free water and may densify low-bulk-density film. | Feed consistency, required handling form and downstream extruder. |
| Air or thermal drying | Provides further moisture reduction when the downstream process requires it. | Measurement method, climate, energy source and final storage. |
| Trattamento dell'acqua | Maintains process-water quality and manages solids, oil and sludge. | Contaminant load, reuse target and local discharge conditions. |
How to compare stated capacity
Do not compare only a nominal kg/h figure. Ask whether capacity is measured as contaminated input, wet intermediate material or dry saleable output. Require the assumed feed composition, operating time, availability, reject rate and output specification. Dense, clean post-industrial film will behave differently from wet agricultural film even when both are called PP/PE.
Every module must support the same design basis. Sorting labour, tanks, dewatering, conveying, water treatment and bagging can limit the line even if the crusher has spare capacity. Buffering helps manage short fluctuations but does not correct a continuously undersized stage.
Wet crushing or dry crushing
Wet crushing can combine size reduction with initial cleaning and material transport. Dry crushing keeps water out of that stage but requires suitable dust, heat and conveying controls. The decision affects wear, water load, floor layout and downstream cleaning. See our detailed comparison of wet and dry crushing in a PE film washing line.
Drying and densification
Film holds water in folds and is difficult to feed at low bulk density. A mechanical dryer removes free water; a squeezer can remove additional water while compacting the material; air or thermal drying may follow when the output specification demands it. No single moisture percentage applies to every film mix and measurement method.
Define where samples are taken, how quickly they are tested, which procedure is used and what feed conditions apply. Also verify whether the densified material is suitable for the planned extruder rather than treating appearance as the only acceptance criterion.
What determines project cost
Equipment price changes with throughput basis, contamination, number of separation and wash stages, construction materials, wear protection, automation, water treatment, drying duty and site-specific engineering. Total project cost may also include freight, foundations, steelwork, lifting, piping, cabling, power distribution, heat supply, wastewater works, commissioning, training and initial spares.
Operating cost should be modeled with local electricity, heat, water, chemical, labour, wear-part and disposal assumptions. Yield is equally important: a cheap line that sends usable material to rejects or produces unstable output can have a higher cost per tonne of saleable product.
Quote and acceptance checklist
- Representative samples and feedstock composition range.
- Input rate and guaranteed saleable output stated separately.
- Output specification, sampling procedure and downstream use.
- Complete equipment, controls, water treatment and utility boundary.
- Layout, local voltage, climate, guarding and compliance requirements.
- Trial material and duration for performance acceptance.
- Training, documentation, spare parts, warranty and service scope.
A process proposal for a complete line is available on our PP/PE film triturazione e densificazione linea pagina.
Domande frequenti
Quale è la capacità giusta per una linea di lavaggio di pellicole PP/PE?
Dipende dal materiale di alimentazione disponibile, dalla contaminazione, dalla quantità di output vendibile richiesta, dal calendario di funzionamento, dalle utenze e dalla domanda a valle. Definire la capacità di output in base alle condizioni materiali concordate prima di selezionare le dimensioni della macchina.
Does every film washing line need hot washing?
No. Temperature and chemistry should be justified by the contamination and product specification. They also increase rinsing, energy and water-treatment requirements.
Does a film squeezer replace washing or separation?
No. A squeezer removes water and densifies prepared film. It does not remove contamination that should have been sorted, washed or separated upstream.
Fonti e ulteriori letture
- Association of Plastic Recyclers: PE Flexible Design Guidance
- CEFLEX: Recyclability Guidelines
- RecyClass: Protocolli di Test
Request a configuration review
Send Energycle representative feedstock information, required output, operating schedule, utilities and site constraints. We can map the necessary modules, capacity basis and supply boundary before preparing a project quotation.
