The PET Bottle Flakes Washing and Recycling Line from Chenxing Machinery is a fully integrated plastic recycling solution engineered to transform post-consumer PET bottles into clean, high-purity flakes ready for direct pelletizing or strapping production. With a scalable capacity range of 500–3000 kg/h, the line covers every stage—label removal, wet crushing, high-temperature steaming, friction washing, dual-tank hot caustic washing, dewatering, and pipe drying—delivering final flakes with moisture content ≤3–5%, flake size 18–22 mm, and bulk density 0.3 g/cm³.
Designed as a core component of any modern PET recycling plant, this line combines robust industrial construction with intelligent process design: counter-current dual-tank washing achieves ≥99% PET purity while reducing fresh water consumption by 30%, and the integrated water recirculation system achieves 85–90% reuse rate. Whether feeding a plastic pelletizer machine or a downstream PET strapping line, this washing line delivers consistent, production-grade output.
The table below presents key parameters across five standard capacity tiers. Values for 1000/1500/2000/3000 kg/h are engineering estimates based on the proven 500 kg/h baseline; actual configurations are tailored to raw material conditions and site requirements.
| Parameter | 500 kg/h | 1000 kg/h | 1500 kg/h | 2000 kg/h | 3000 kg/h |
|---|
| Raw Material | PET bottles & flakes | PET bottles & flakes | PET bottles & flakes | PET bottles & flakes | PET bottles & flakes |
| Capacity | 500 kg/h | 1000 kg/h | 1500 kg/h | 2000 kg/h | 3000 kg/h |
| Total Installed Power | 146 kW | ≈220 kW | ≈300 kW | ≈380 kW | ≈520 kW |
| Actual Power Draw | 70–80% (≈102–117 kW) | 70–80% (≈154–176 kW) | 70–80% (≈210–240 kW) | 70–80% (≈266–304 kW) | 70–80% (≈364–416 kW) |
| Water Consumption | 10–12 m³/h | 18–22 m³/h | 25–30 m³/h | 32–38 m³/h | 45–55 m³/h |
| Water Pressure | 0.6 MPa | 0.6 MPa | 0.6 MPa | 0.6 MPa | 0.6 MPa |
| Heat Supply Temp. | 170°C / 0.7 MPa | 170°C / 0.7 MPa | 170°C / 0.7 MPa | 170°C / 0.7 MPa | 170°C / 0.7 MPa |
| Operators Required | 3–6 persons | 4–8 persons | 5–10 persons | 6–12 persons | 8–15 persons |
| Workshop Footprint (L×W×H) | 50×15×5 m | 60×20×6 m | 70×22×6 m | 80×25×6 m | 90×28×7 m |
| Power Supply | 380V / 50Hz / 3-Phase | 380V / 50Hz / 3-Phase | 380V / 50Hz / 3-Phase | 380V / 50Hz / 3-Phase | 380V / 50Hz / 3-Phase |
| Delivery Time | 50–60 working days | 55–65 working days | 60–70 working days | 65–75 working days | 70–85 working days |
| Warranty | 1 year | 1 year | 1 year | 1 year | 1 year |
| Payment Terms | 30% T/T advance, 70% before delivery | 30% T/T advance, 70% before delivery | 30% T/T advance, 70% before delivery | 30% T/T advance, 70% before delivery | 30% T/T advance, 70% before delivery |
Note: Wires, cables, and water supply piping from the main utility connection to equipment are customer-supplied. An overhead crane for equipment installation and maintenance is also the customer's responsibility.
The line comprises 13 core machines arranged in a sequential process flow. Each unit serves a distinct function with specific process parameters.
| No. | Equipment | Qty | Function | Key Process Data |
|---|
| 1 | Belt Conveyor | 1 set | Feeds baled/loose PET bottles into the line at a controlled rate; manual or automatic sorting station can be integrated. | Conveyor speed adjustable to match downstream crusher throughput |
| 2 | Crusher (Wet Type) | 1 set | Wet crushes whole PET bottles into 18–22 mm flakes. Water is injected during crushing to pre-clean surfaces and reduce blade wear. | Flake size: 18–22 mm; wet crushing preserves flake integrity and reduces dust |
| 3 | Screw Loader | 1 set | Transports crushed flakes from crusher to steamer via inclined screw conveyor; perforated trough allows free water drainage. | — |
| 4 | Steamer (Hot Washer) | 1 set | High-temperature steaming at 85–95°C with 1.5–2.5% NaOH solution. PVC labels shrink at 70–80°C and detach; adhesives begin hydrolyzing. Retention time: 8–12 min. | Temperature: 85–95°C; NaOH: 1.5–2.5%; Retention: 8–12 min |
| 5 | Screw Loader | 1 set | Transfers steamed flakes to friction washer. | — |
| 6 | Friction Washer | 1 set | High-speed rotating paddles generate intense mechanical friction between flakes to scrub off remaining surface contaminants, soil, and loosened adhesives. | High RPM friction action; water-assisted scrubbing |
| 7 | Poaching Tank #1 | 1 set | First-stage hot caustic washing at ~85°C. Removes paper pulp from labels, surface mud, and bulk contaminants. This tank bears the heaviest dirt load. | NaOH: 1.5–2.5%; Temperature: ~85°C; Retention: 10–15 min |
| 8 | Screw Loader | 1 set | Transfers flakes from Poaching Tank #1 to Poaching Tank #2. | — |
| 9 | Poaching Tank #2 | 1 set | Second-stage hot caustic washing at 90–95°C with fresh alkali solution. Thoroughly hydrolyzes residual adhesives and removes fine contaminants. Counter-current overflow from Tank #2 feeds Tank #1, saving 30% water. | NaOH: 1.5–2.5%; Temperature: 90–95°C; Retention: 10–15 min; Counter-current design |
| 10 | Screw Loader | 1 set | Transfers washed flakes to dewatering machine. | — |
| 11 | Dewatering Machine | 1 set | Vertical or horizontal high-speed centrifugal dewatering; reduces surface moisture to ≤3–5% before thermal drying. | Final moisture: ≤3–5% |
| 12 | Pipe Drying System & Silo | 1 set | Pneumatic hot-air pipe dryer transports and thermally dries flakes into the storage silo. Silo provides buffering for continuous downstream processing. | Bulk density: 0.3 g/cm³ in silo |
| 13 | Electric Appliance (Control Cabinet) | 1 set | Centralized PLC-based control panel managing all motors, temperature zones, and safety interlocks across the entire line. | 380V/50Hz, 3-Phase; overload and phase-loss protection |
Label Stripper / Decalifier: Mechanically removes 90–95% of labels before crushing. Reduces downstream chemical load and improves final flake purity. Highly recommended for lines processing heavily labeled bottles.
PET Strap Production Line or Pelletizing Line: Downstream turnkey integration—connect the silo output directly to a plastic pelletizer for granulation or a PET strap extrusion line for finished strapping products.
The line handles a wide range of post-consumer PET bottle streams. The table below summarizes common material types, associated contaminants, and the process strategies deployed.
| Material Type | Typical Contaminants | Processing Strategy |
|---|
| Transparent PET Bottles | Light soil, beverage residue, paper labels | Standard hot caustic washing; highest-value output flake for fiber-grade applications |
| Blue-Tinted PET Bottles | Same as transparent; blue tint does not separate | Processed together with transparent bottles; acceptable for most PET recycling applications |
| Green PET Bottles | Same as transparent; green tint remains | Processed together; color sorting (optional optical sorter) recommended if color-separated flakes are required |
| PET Bottles with PVC Labels | PVC labels (density ~1.38–1.42 g/cm³), adhesives | Steamer shrinks PVC at 70–80°C → mechanical detachment; residual PVC fragments separated via hydro-cyclone or zig-zag air classifier |
| PET Bottles with PE/PP Caps | PE/PP caps (density 0.90–0.97 g/cm³, float), cap rings | Float-sink separation in poaching tanks: PE/PP floats, PET sinks (density 1.35–1.40 g/cm³); caps skimmed from water surface |
| Heavily Oiled / Soiled Bottles | Cooking oil, grease, mud, organic residues | Extended retention in Poaching Tank #1; increased NaOH concentration (2.5%) and temperature (90–95°C); optional pre-soak stage |
The steamer + dual-tank hot caustic washing combination is the cornerstone of the line's cleaning performance. Operating at 85–95°C with 1.5–2.5% NaOH, the system causes PVC labels to shrink and detach at 70–80°C while hydrolyzing adhesives into water-soluble compounds. The optional label stripper removes 90–95% of labels mechanically before crushing, significantly reducing downstream chemical consumption.
Two poaching tanks operate in series with counter-current water flow: fresh water enters Tank #2 (the cleaner stage), overflows to Tank #1 (the dirtier pre-wash stage), then exits for treatment. This cascade design achieves two critical advantages: (a) 30% water savings versus single-tank systems, and (b) progressive dilution of contaminants, preventing soiled water from re-depositing onto cleaned flakes. Single-tank systems typically achieve only 80–85% glue removal; the dual-tank cascade reaches ≥99%.
Unlike dry crushing—which generates excessive fines, heat, and dust—wet crushing injects water directly into the crusher chamber, cooling blades and lubricating the cut. This produces cleanly cut 18–22 mm flakes with minimal micro-fractures and powdery residue, maximizing the yield of usable flake for pelletizing and extrusion.
The line exploits natural density differences between bottle materials for passive separation:
| Material | Density | Behavior in Water | Separation Mechanism |
|---|
| PET | 1.35–1.40 g/cm³ | Sinks | Remains in tank for processing |
| PP / PE (caps) | 0.90–0.97 g/cm³ | Floats | Skimmed from water surface |
| PVC (labels) | 1.38–1.42 g/cm³ | Sinks | Shrunk & detached in steamer; residual separated via hydro-cyclone or air classifier |
This multi-stage approach—mechanical detachment + float-sink + optional air classification—delivers final PET purity of ≥99%.
The high-speed centrifugal dewatering machine reduces surface moisture to ≤3–5%, followed by pneumatic pipe drying that further stabilizes the flakes at ≤3–5% before storage. Flakes at this moisture level can be fed directly into single-screw extruders or pelletizing lines without an additional pre-drying step—saving energy and floor space.
The line is built on a modular equipment platform: each machine (crusher, steamer, poaching tank, dewaterer, dryer) is independently sized, allowing the same proven process to scale from 500 to 3000 kg/h. Expanding capacity is a matter of upsizing or duplicating individual modules rather than redesigning the entire line. This modularity also simplifies maintenance—individual units can be serviced without shutting down the entire plant.
The integrated water treatment loop processes process water through: wedge-wire screen (>1 mm solids removal) → sedimentation basin → chemical flocculation (PAC + PAM) → inclined plate clarifier → sand filter → reuse. Fresh water make-up is reduced to just 1.5–2.0 m³/h for the 500 kg/h line (85–90% recirculation rate). Concentrated sludge is dewatered via filter press to ≤60% moisture for solid waste disposal. Full auxiliary machine solutions including water treatment equipment are available.
The silo discharge port is designed for seamless connection to downstream equipment. Chenxing Machinery offers integrated solutions including PET strapping band extrusion lines, pelletizing systems, and PVC pipe extrusion lines. Buyers can source a complete "bottle-to-product" plant from a single supplier, ensuring process compatibility and unified after-sales support. Supporting equipment—hopper dryers, vacuum loaders, chillers, and pipe coilers—are also available from our full product catalog.
The complete washing and recycling process follows seven sequential stages, each with documented process parameters.
Baled or loose PET bottles are loaded onto the belt conveyor at a controlled feed rate matched to line capacity. An optional manual sorting station allows operators to remove obvious non-PET contaminants (stones, metals, colored non-PET plastics) before crushing. If equipped, the label stripper / decalifier mechanically peels off 90–95% of bottle labels at this stage.
Bottles enter the wet crusher, where rotating blades slice them into 18–22 mm flakes under a continuous water spray. The water serves three purposes: (a) cooling blades to prevent heat-induced PET degradation, (b) pre-washing loose surface dirt, and (c) suppressing dust. Wet crushing produces clean-edged flakes with minimal fines.
Crushed flakes are screw-fed into the steamer, where they are agitated in a 85–95°C bath of 1.5–2.5% NaOH solution for 8–12 minutes. At these conditions: PVC labels shrink (70–80°C) and mechanically detach; paper labels disintegrate into pulp; and adhesives begin alkaline hydrolysis. This is the most energy-intensive stage but critical for downstream purity.
Flakes pass through the friction washer—a high-speed rotating paddle system that generates intense flake-to-flake and flake-to-wall scrubbing. Water jets continuously flush away loosened contaminants. This mechanical action removes stubborn surface soils, residual label fragments, and partially hydrolyzed adhesives that survived steaming.
This is the heart of the cleaning system:
Poaching Tank #1 (Pre-Wash): Operates at ~85°C, handling the majority of paper pulp, mud, and bulk contamination. Water here is turbid by design—it absorbs the heaviest dirt load.
Poaching Tank #2 (Fine-Wash): Operates at 90–95°C with cleaner, fresher alkali solution. Residual adhesives undergo complete hydrolysis; fine particles are removed. Retention time: 10–15 minutes per tank.
Counter-current flow: Fresh water enters Tank #2 → overflows to Tank #1 → exits for treatment. This cascade saves 30% water and ensures flakes leaving Tank #2 are washed with the cleanest water in the system.
Washed flakes are transferred to the centrifugal dewatering machine. High-speed rotation (vertical or horizontal axis) spins off surface water, reducing moisture content to ≤3–5%. This mechanical step is energy-efficient compared to thermal drying alone and dramatically reduces the heat load on the downstream dryer.
Partially dried flakes enter the pneumatic pipe drying system, where hot air (sourced from the plant's heat supply, 170°C / 0.7 MPa) carries and simultaneously dries the flakes through an insulated duct. Dried flakes (moisture ≤3–5%, bulk density 0.3 g/cm³) are deposited into the storage silo, ready for bagging or direct feed to a pelletizing line or PET strap production line. For integrated plants, a vacuum conveyor loader can automate silo-to-extruder material transfer.
The system combines thermal, chemical, and mechanical mechanisms. In the steamer, PET flakes are agitated at 85–95°C in a 1.5–2.5% NaOH solution for 8–12 minutes. At this temperature, PVC labels shrink at 70–80°C and physically detach from bottle fragments, while paper labels disintegrate into pulp. Simultaneously, the alkaline solution hydrolyzes common bottle adhesives (acrylate-based and starch-based), breaking their polymer chains into water-soluble fragments. The downstream dual-tank poaching system provides an additional 20–30 minutes of cumulative retention (10–15 min per tank) to complete the hydrolysis. When the optional label stripper is installed upstream, it mechanically removes 90–95% of labels before crushing, significantly reducing the chemical and thermal load on the steamer. For comprehensive recycling solutions, including washing and downstream pelletizing, contact our engineering team.
Separation exploits the density differences between PET, polyolefin caps, and label materials. PET (1.35–1.40 g/cm³) sinks in water, while PP/PE caps (0.90–0.97 g/cm³) float and are continuously skimmed from the surface of poaching tanks and float-sink separation channels. This achieves near-complete removal (>99%) of polyolefin caps in a single pass. PVC labels present a greater challenge: at 1.38–1.42 g/cm³, their density overlaps with PET, so simple float-sink is insufficient. The line addresses this via (a) thermal shrinking in the steamer (70–80°C) causing PVC labels to curl and detach, (b) mechanical friction washing to dislodge loosened fragments, and (c) an optional zig-zag air classifier or hydro-cyclone for final separation of any residual lightweight fragments (paper scraps, film bits). The result is final PET purity of ≥99%.
A dual-tank counter-current design delivers both higher cleanliness and lower water consumption compared to a single tank:
| Criterion | Single Tank | Dual Tank (Counter-Current) |
|---|
| Adhesive Removal Rate | 80–85% | ≥99% |
| Water Consumption | Baseline | 30% less (Tank #2 overflow feeds Tank #1) |
| Recontamination Risk | High: paper pulp and mud re-attach to flakes | Low: flakes exit through the cleanest water |
| Process Control | One setpoint for all stages | Independent temperature & concentration per stage |
In Tank #1 (~85°C), the dirtiest work occurs—bulk paper pulp, surface mud, and most label residue are removed. The water here is intentionally turbid. In Tank #2 (90–95°C), fresh alkali solution completes the adhesive hydrolysis on pre-cleaned flakes. The counter-current overflow from Tank #2 to Tank #1 ensures that flakes leaving the system are always washed with the cleanest available water while the dirtiest water exits with the heaviest contaminants—a classic counter-current extraction principle adapted for solid-liquid washing. For facilities processing diverse bottle streams, this design is essential for consistent output quality suitable for high-output extrusion.
In once-through (no recycling) mode, the 500 kg/h line consumes 10–12 m³/h of fresh water. With the integrated water treatment and recirculation system, fresh water make-up drops to just 1.5–2.0 m³/h—an 85–90% reuse rate.
The water treatment train: Wedge-wire screen (removes solids >1 mm) → Sedimentation basin (gravity settling of sand and silt) → Chemical flocculation (PAC coagulant + PAM flocculant dosing) → Inclined plate clarifier (accelerated solids settling) → Sand filter (polishing) → Reuse tank → Return to process. Concentrated sludge from the clarifier is dewatered via a plate-and-frame filter press to ≤60% moisture for solid waste disposal. The system is designed for 24/7 continuous operation with automated chemical dosing and sludge discharge. Supporting equipment such as chillers can be integrated for temperature-sensitive processes. Detailed water treatment sizing tailored to site conditions is provided with every quotation.
The washing line output delivers flakes with moisture ≤3–5%, flake size 18–22 mm, bulk density 0.3 g/cm³, PET purity ≥99%, and intrinsic viscosity (IV) typically in the 0.70–0.80 dL/g range. These flakes are directly suitable for: (a) polyester staple fiber and filament yarn (≥99% purity suffices), (b) PET strapping band production, (c) PET sheet and thermoforming, and (d) engineering-grade PET compounds. For bottle-to-bottle (B2B) food-contact applications (e.g., new beverage bottles), the washed flakes must undergo an additional Solid-State Polycondensation (SSP) process to raise IV to ≥0.80 dL/g, followed by EFSA/FDA-compliant decontamination and certification. The washing line is the critical front-end step—if cleaning is inadequate (residual adhesives, PVC fragments, or low purity), no amount of downstream SSP can compensate. Our line is specifically engineered to produce SSP-ready flakes with the consistency required for food-grade applications. For turnkey projects including pelletizing, explore our plastic pelletizer machines and complete production lines.
Every PET washing line is configured based on your raw material profile, throughput target, and end-product specification. Our engineers analyze your bottle stream (label types, cap materials, contamination level, color mix) and size each unit—crusher, steamer, poaching tanks, dewaterer—to match. This is not a fixed catalogue of pre-packaged models; it is process engineering tailored to your factory floor.
Unlike many competitors who default to single-tank washing (adhesive removal: 80–85%), we build the dual-tank counter-current system into every line as standard. This delivers ≥99% adhesive removal with 30% less water—a measurable difference in both flake quality and operating cost, backed by news and case studies from installations worldwide.
Chenxing Machinery manufactures not just washing lines but the complete downstream ecosystem: single-screw extruders, plastic heating mixers, pelletizers, embossing machines, and full extrusion lines. Buy a washing line today, add a pelletizing line tomorrow—same supplier, same service team, guaranteed compatibility.
Every line includes a 1-year comprehensive warranty on all mechanical and electrical components. Our support extends beyond warranty: remote diagnostics, spare parts dispatch from stock, and on-site commissioning engineers available for installation and operator training. Learn more about us and our commitment to after-sales service.
Step 1 — Tell Us Your Requirements Send us your target capacity (kg/h), typical bottle source (municipal collection / deposit system / industrial scrap), and the desired end use of the flakes (fiber / strapping / pelletizing / food-grade). Photos or videos of your raw material are extremely helpful.
Step 2 — Receive a Tailored Proposal Our engineering team will respond within 1–2 business days with a customized line configuration, equipment list, 3D layout drawing proposal, and a detailed quotation including water treatment and optional equipment.
Step 3 — Factory Visit or Virtual Tour Visit our manufacturing facility in Zhangjiagang, Jiangsu, China, to see lines under assembly and witness a live production demonstration. Alternatively, we offer a video walkthrough of an operating reference line.
Step 4 — Production, Delivery & Commissioning After order confirmation (30% T/T deposit), manufacturing begins. Delivery within 50–60 working days. Our commissioning engineers travel to your site for installation, start-up, operator training, and performance acceptance testing.