Aralin 1Mga pamamaraan ng dewatering at drying: centrifuges, thermal dryers, vacuum, target moisture levels bago ang extrusionNakatuon sa dewatering at drying ng washed flakes bago ang extrusion. Inihahalintulad ang centrifuges, mechanical dewatering, thermal at vacuum dryers, at tinutukoy ang target moisture levels para sa iba't ibang polymers upang maiwasan ang hydrolysis, voids, at processing instability.
Mechanical dewatering: screw presses and centrifugesThermal dryers: hot air, infrared, and contact typesVacuum drying for hygroscopic polymers like PETTarget moisture levels for PET, PA, and othersEnergy optimization and dryer performance controlAralin 2Solid-state cleaning at post-extrusion steps: melt filtration, solid-state polycondensation (SSP) para sa IV recovery sa PETTinatalakay ang mga post-extrusion steps para sa high-performance recyclates, kabilang ang melt filtration polishing, pellet cooling, at solid-state polycondensation para sa PET IV recovery. Ipinaliliwanag ang mga kondisyon ng proseso, quality control, at regulatory considerations para sa food-contact use.
Melt filtration polishing and fine contaminant removalStrand and underwater pelletizing system choicesSolid-state polycondensation principles for PETIV monitoring, residence time, and temperatureFood-contact compliance and decontamination testsAralin 3Separation at density-based processes: float-sink tanks, hydrocyclones, specific gravity windows para sa PET/PE separationIpinaliliwanag ang density-based separation na ginagamit sa recycling, kabilang ang float-sink tanks at hydrocyclones. Inilalarawan ang specific gravity windows para sa karaniwang polymers, process water conditioning, at kung paano nakakaapekto ang operating parameters sa separation sharpness at yield.
Principles of density separation in water mediaFloat-sink tank design and operating parametersHydrocyclone configuration and cut-point controlSpecific gravity windows for PET, PE, and PPWater chemistry, surfactants, and contaminationAralin 4Reception at pre-sorting: manual sorting, trommels, ballistic separators, size at throughput considerationsIpinaliliwanag ang reception at pre-sorting ng incoming plastic waste. Tinatalakay ang feed inspection, manual picking, trommels, at ballistic separators, na may diin sa pag-alis ng non-conformities, pamamahala ng throughput, at paghahanda ng stable feed para sa automated sorting.
Incoming load inspection and quality checksManual sorting stations and ergonomicsTrommel screens for size classificationBallistic separators for 2D and 3D separationBalancing throughput, staffing, and safetyAralin 5Reject handling at residue processing: contaminants, fines, wastewater solids, at safe disposal o valorization optionsTinatalakay ang paghawak ng rejects at residues mula sa sorting, washing, at extrusion. Tinutugunan ang mga karaniwang kontaminante, fines, at wastewater solids, na may mga opsyon para sa safe disposal, energy recovery, o material valorization habang sumusunod sa environmental at regulatory requirements.
Typical contaminants and off-spec plastic streamsCollection and treatment of fines and dustWastewater solids thickening and dewateringSafe landfill, co-processing, and incineration routesValorization options: RDF, co-processing, and reuseAralin 6Sizing at shredder options: coarse shredding, granulators, knife mills, particle size targets at energy useTinutukoy ang mga size reduction strategies mula sa coarse shredding hanggang sa fine granulation. Ipinaliliwanag ang mga uri ng kagamitan, rotor at knife configurations, at kung paano nakakaapekto ang particle size targets, throughput, at energy consumption sa downstream washing, drying, at extrusion performance.
Coarse shredders for bulky plastic feedstocksGranulator design, rotor types, and screen selectionKnife mill applications and wear managementParticle size targets for film, rigid, and fiberEnergy use, throughput, and maintenance trade-offsAralin 7Automated sorting technologies: NIR, VIS cameras, float-sink, eddy current, X-ray at typical sorting efficienciesInilalarawan ang mga automated sorting technologies na ginagamit sa plastic recycling, kabilang ang NIR at VIS systems, float-sink, eddy current, at X-ray. Sinuri ang mga karaniwang sorting efficiencies, limitations, at kung paano nakakaapekto ang disenyo ng sistema sa purity, yield, at operating costs.
NIR sorting for polymer type identificationVIS cameras for color and label detectionEddy current separators for non-ferrous metalsX-ray systems for PVC and metal contaminationSorting efficiency, purity, and yield metricsAralin 8Washing at cleaning stages: hot-wash, counter-current washers, caustic washes, surfactant use, temperatures at residence timesTinutukoy ang mga washing at cleaning stages para sa plastic flakes, kabilang ang pre-wash, hot-wash, caustic at surfactant systems. Tinalakay ang temperature, residence time, mechanical action, at kung paano tinatanggal ng disenyo ng proseso ang labels, adhesives, at organic residues.
Pre-wash and friction washer configurationsHot-wash conditions for label and glue removalCaustic washing chemistry and controlSurfactant selection and foaming managementResidence time, agitation, and soil loadingAralin 9Compounding at additive dosing: stabilizers, odor absorbers, impact modifiers, dosing system considerationsSinusuri ang compounding ng recycled plastics, na nakatuon sa stabilizers, odor control, impact modifiers, at colorants. Tinalakay ang dosing technologies, feeding accuracy, dispersion quality, at kung paano inaangkop ang additive packages sa target applications at regulatory limits.
Thermal and UV stabilizers for recycled resinsOdor absorbers and deodorization approachesImpact modifiers and toughness enhancementColor masterbatches and pigment selectionGravimetric and volumetric dosing system designAralin 10Extrusion, filtration at degassing: single-screw vs twin-screw, melt filtration (screen changers, pore sizes), melt temperature rangesInilalahad ang extrusion sa mechanical recycling, na naghahambing ng single-screw at twin-screw designs, melt temperature control, at degassing. Tinatalakay ang melt filtration hardware, pore size selection, at kung paano nakakaapekto ang mga factor na ito sa contaminant removal at pellet quality.
Single-screw extruder design and operating windowsTwin-screw extruders for compounding and devolatilizationMelt temperature control and residence time effectsMelt filtration hardware, screen changers, pore sizesVacuum degassing, vent design, and volatile removal
