Two plants can both say they “recycle plastic” and still require very different equipment. The biggest divider is where the feedstock comes from:
- Post-industrial (often called PIR): factory scrap and production waste generated in controlled settings
- Post-consumer (often called PCR): waste collected after use from households and commercial sources
This distinction matters because it changes contamination risk, water usage, sorting needs, and melt filtration requirements. If you design a PCR project like a PIR project, it may “run,” but it often produces inconsistent output, higher downtime, and lower saleable yield.
Conclusioni rapide
- PIR is usually cleaner and more consistent; many lines can reduce or skip washing.
- PCR is often wet, dirty, and mixed; sorting and washing become core modules.
- As contamination and moisture increase, filtration and degassing requirements increase.
- Compare proposals on saleable output per hour under a defined feedstock condition, not only on machine size.
PIR vs PCR: The Practical Differences That Drive Equipment Choices
| Fattore | Post-Industrial (PIR) | Post-Consumer (PCR) | Why Buyers Care |
|---|---|---|---|
| Coerenza | Usually stable by source and supplier | Often variable by batch and season | Variability causes downtime and quality drift. |
| Sorting intensity | Often minimal | Often required (metals, non-target polymers) | Sorting protects equipment and raises product value. |
| Washing / water management | Sometimes reduced or skipped | Commonly required; water management becomes a system | Dirty water becomes dirty flakes; water control affects yield. |
| Umidità | Often lower and more stable | Often higher and less predictable | Moisture drives drying cost and extrusion stability. |
| Filtrazione a fusione | Basic filtration may be enough | Higher load; stronger filtration strategy often required | Filtration downtime can dominate saleable output. |
What a Typical PIR Line Looks Like (And Why It Can Be Simple)
Typical PIR sources include edge trim, startup purge, off-spec parts, and factory scrap. Many streams are single-polymer and relatively clean.
Common equipment approach (varies by polymer and form factor):
1) size reduction (only if needed) 2) densification/controlled feeding (especially for film and light scrap) 3) extrusion and pelletizing with basic filtration
This is why many PIR projects start with a compactor-pelletizer style system rather than a full washing line. Energycle’s macchine per la pellettizzazione della plastica overview is a useful reference for pelletizing terminology when you compare proposals.
What Changes in PCR (And Why PCR Lines Need More “Modules”)
PCR streams often include:
- dirt, sand, paper, and labels
- food residue and oils
- mixed polymers and non-plastic items
- inconsistent moisture and bale quality
As a result, PCR equipment lists commonly add:
- sorting and metal removal up front
- full washing and separation stages (often with hot wash depending on polymer and contamination)
- dewatering and drying sized for wet material
- stronger melt filtration to handle higher contaminant load
- vacuum degassing for moisture and volatiles when pelletizing
If PCR cleanliness and repeatability matter, it is usually better to start from a full washing concept. Energycle’s sistema di lavaggio a riciclo is a reference point for the modules that show up in PCR projects.
Typical Equipment Emphasis by PCR Stream (Examples)
PCR is not one stream. These examples show how “PCR” changes the equipment emphasis:
| PCR stream | What usually drives complexity | Modules that often decide success |
|---|---|---|
| bottiglie in PET | PVC risk, label/adhesive removal, stable washing and drying | Sorting, hot wash control, rinsing, drying/moisture control |
| PE/PP film | Low bulk density, high surface contamination, dewatering difficulty | Feeding/densification, strong washing, dewatering and filtration planning |
| Rigid PP/HDPE packaging | Labels, paper, occasional metals and non-target polymers | Pre-sorting, washing consistency, separation and QC checkpoints |
The Hidden PCR Problem: Variability (Not Only Dirt)
PIR tends to behave predictably; PCR does not. Even within one “bale grade,” composition can drift based on collection method, season, and local packaging mix.
If you are building a PCR line, plan for:
- inbound sampling and bale audits (typical and worst-case)
- an operating window that covers good and bad batches
- QC checkpoints (PVC risk for PET, ash/fines indicators, moisture checks, filtration pressure trend if pelletizing)
The goal is not to design for “perfect input.” The goal is to design for a defined operating window that you can buy and manage.
Output Choice: Flake vs Pellets (Where PCR and PIR Diverge Again)
Many plants assume “pelletizing is the final step,” but the best choice depends on your end market and your quality targets.
- Flake output can be the right business model if you have buyers who pelletize or compound, and if you can hit cleanliness and moisture targets consistently.
- Pellet output can increase market flexibility, but it adds extrusion, filtration, and tighter moisture control. For PCR, it often requires more stable upstream washing and drying.
If you are deciding between flakes and pellets, start from your buyer’s acceptance tests and penalties for drift, then map equipment to those tests.
What to Put in Your RFQ (So Quotes Are Comparable)
Many “cheap” proposals are cheap because the input assumptions are unrealistically clean. To avoid that, put these items in your RFQ:
- polymer(s), form factor, and the contamination window you expect
- moisture at key points (inbound and after washing, if known)
- target output (flakes or pellets) and how it is tested
- throughput definition: saleable output per hour under defined feedstock conditions
- expected duty cycle (shifts and hours)
If you share photos of your material and your target product spec, Energycle can recommend a line concept via its pagina dei contatti.
FAQ (Domande reali sugli appalti)
1) Can I run PCR on a “PIR-style” pelletizer without washing?
Sometimes for relatively clean streams, but it is a higher-risk path. PCR variability shows up as moisture swings, contamination spikes, and more downtime from filtration and cleaning. A pelletizer can be tuned to run on a good day and still struggle on a bad day. If you want to test feasibility, define a representative “worst-case” feedstock condition and run a trial that measures saleable output, restart scrap, and filtration behavior. If the line requires constant operator intervention or frequent stops, the economics usually shift in favor of adding sorting and washing rather than pushing a simple system beyond its tolerance window.
2) What are the first three upgrades that usually pay back on PCR (before buying bigger machines)?
Most PCR efficiency gains come from stabilizing input and cleanliness, not from increasing motor size. First, tighten inbound QC and sorting to keep metals and non-target polymers out. Second, stabilize washing and separation so water quality and residence time do not drift. Third, improve dewatering and drying control so moisture at extrusion feed is stable. These upgrades reduce unplanned stops and increase saleable yield. Bigger equipment only helps when the process is already stable. If you share your stream details, Energycle can help map upgrades to bottlenecks through its pagina dei contatti.
3) How should I define “throughput” so suppliers don’t quote unrealistic numbers?
Request throughput as saleable product per hour at a defined feedstock condition. Specify polymer, moisture, and a contamination window (labels/paper/sand/metals). Then require assumptions: screen-change interval, planned cleaning downtime, operator count, and expected scrap/restart losses. Without those definitions, suppliers can inflate “capacity” by assuming cleaner material or by ignoring downtime and yield loss. A good RFQ ties performance to measurable conditions and acceptance tests. This makes different proposals comparable and protects you from buying assumptions instead of equipment performance.
4) Do I always need pelletizing, or can I sell flakes?
You can sell flakes if your buyers accept your cleanliness, moisture, and size distribution. Flake selling can reduce capex and simplify operations because you avoid extrusion, filtration, and pellet quality management. Pelletizing can increase market flexibility, but it requires stable upstream cleaning and moisture control, plus more process skill. Start by asking buyers what tests they use and what they reject (specks, paper, odor, moisture, melt flow). Then choose the output form that matches your market and your operating capability. If you plan to pelletize, Energycle’s macchine per la pellettizzazione della plastica page helps align pelletizing terminology across quotes.
5) What reference documents help me write a realistic bale and contamination specification?
Use an industry reference for contamination language, then adapt it to your stream and end market. The Association of Plastic Recyclers (APR) model bale specifications are widely used as a starting point for describing bale quality factors and contaminants. The goal is not “perfect bales”—it is a bale quality window your line can process without constant stops and quality drift. Write requirements for the contaminants that damage quality (for example, PVC risk items in PET) and the contaminants that damage uptime (metals, stones, high dirt). Then align inbound QC with those requirements so the spec is enforceable.
