[go: up one dir, main page]

WO2008035185A2 - Appareil et procédé d'extrusion de matériau plastique - Google Patents

Appareil et procédé d'extrusion de matériau plastique Download PDF

Info

Publication number
WO2008035185A2
WO2008035185A2 PCT/IB2007/002729 IB2007002729W WO2008035185A2 WO 2008035185 A2 WO2008035185 A2 WO 2008035185A2 IB 2007002729 W IB2007002729 W IB 2007002729W WO 2008035185 A2 WO2008035185 A2 WO 2008035185A2
Authority
WO
WIPO (PCT)
Prior art keywords
conveyor
plastic material
supply hopper
extrusion
extrusion apparatus
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/IB2007/002729
Other languages
English (en)
Other versions
WO2008035185A3 (fr
Inventor
Albino Rossi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
FERIOLI FILIPPO SpA
Original Assignee
FERIOLI FILIPPO SpA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by FERIOLI FILIPPO SpA filed Critical FERIOLI FILIPPO SpA
Publication of WO2008035185A2 publication Critical patent/WO2008035185A2/fr
Publication of WO2008035185A3 publication Critical patent/WO2008035185A3/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/78—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling
    • B29C48/80—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling at the plasticising zone, e.g. by heating cylinders
    • B29C48/83—Heating or cooling the cylinders
    • B29C48/834—Cooling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/03—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor characterised by the shape of the extruded material at extrusion
    • B29C48/04—Particle-shaped
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/27—Cleaning; Purging; Avoiding contamination
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/285—Feeding the extrusion material to the extruder
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/285—Feeding the extrusion material to the extruder
    • B29C48/287—Raw material pre-treatment while feeding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/375—Plasticisers, homogenisers or feeders comprising two or more stages
    • B29C48/39—Plasticisers, homogenisers or feeders comprising two or more stages a first extruder feeding the melt into an intermediate location of a second extruder
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/50—Details of extruders
    • B29C48/74—Bypassing means, i.e. part of the molten material being diverted into downstream stages of the extruder
    • B29C48/745—Bypassing means, i.e. part of the molten material being diverted into downstream stages of the extruder for plasticising or homogenising devices
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/50—Details of extruders
    • B29C48/76—Venting, drying means; Degassing means
    • B29C48/765—Venting, drying means; Degassing means in the extruder apparatus
    • B29C48/766—Venting, drying means; Degassing means in the extruder apparatus in screw extruders
    • B29C48/767—Venting, drying means; Degassing means in the extruder apparatus in screw extruders through a degassing opening of a barrel
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/78—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling
    • B29C48/793—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling upstream of the plasticising zone, e.g. heating in the hopper
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/78—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling
    • B29C48/80—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling at the plasticising zone, e.g. by heating cylinders
    • B29C48/83—Heating or cooling the cylinders
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/78—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling
    • B29C48/80—Thermal treatment of the extrusion moulding material or of preformed parts or layers, e.g. by heating or cooling at the plasticising zone, e.g. by heating cylinders
    • B29C48/83—Heating or cooling the cylinders
    • B29C48/832—Heating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/285—Feeding the extrusion material to the extruder
    • B29C48/297—Feeding the extrusion material to the extruder at several locations, e.g. using several hoppers or using a separate additive feeding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C48/00—Extrusion moulding, i.e. expressing the moulding material through a die or nozzle which imparts the desired form; Apparatus therefor
    • B29C48/25—Component parts, details or accessories; Auxiliary operations
    • B29C48/36—Means for plasticising or homogenising the moulding material or forcing it through the nozzle or die
    • B29C48/50—Details of extruders
    • B29C48/76—Venting, drying means; Degassing means
    • B29C48/762—Vapour stripping
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29K—INDEXING SCHEME ASSOCIATED WITH SUBCLASSES B29B, B29C OR B29D, RELATING TO MOULDING MATERIALS OR TO MATERIALS FOR MOULDS, REINFORCEMENTS, FILLERS OR PREFORMED PARTS, e.g. INSERTS
    • B29K2105/00—Condition, form or state of moulded material or of the material to be shaped
    • B29K2105/26—Scrap or recycled material

Definitions

  • the present invention relates to an apparatus for extrusion of plastic material.
  • the present invention regards an apparatus for extrusion of recycled plastic material with a high content of residual humidity for the production of pellets.
  • An apparatus for extrusion of plastic material of a known type comprises: a supply hopper for supply of the plastic material; an extrusion head; and a first conveyor for fluidifying, compressing, heating, and feeding the plastic material in a direction of advance from the supply hopper to the extrusion head.
  • the type of extrusion apparatus identified above has proven to be particularly efficient in carrying out extrusion of recycled plastic material containing a low level of humidity. Instead, the type of extrusion apparatus identified above has proven ineffective in carrying out extrusion of recycled plastic material with a content of humidity higher than 0.5 wt% because the high content of residual humidity generates vapour that jeopardizes proper formation of the pellets.
  • conventional recycling of plastic material envisages the steps of: selecting the packages for eliminating any possible extraneous fractions; dividing the packages according to the type of polymer of which they are made; breaking up and shredding the packages into flakes of a homogeneous albeit irregular size; washing the flakes for eliminating any possible contaminants or other elements that could be harmful in the subsequent processing operations; possibly shredding the flakes of plastic material more finely in order to obtain flakes of smaller size; centrifuging the flakes of plastic material in a centrifuge to reduce the content of humidity from 20-25 wt% to 5-8 wt%; and thickening the flakes of plastic material in a densifier in order to reduce the content of humidity to a value lower than 0.5 wt% and rendering the content of humidity of the plastic material compatible with the apparatuses for extrusion of a known type.
  • the centrifuge and the densifier are apparatuses that are costly and of large dimensions, also considering the fact that the recycling method is applied to relatively large masses of plastic material.
  • the densifier requires a very high energy consumption. Consequently, recycling of the plastic material is a costly method, and a conspicuous part of the costs is determined by the necessary reduction in the content of humidity of the plastic material.
  • the aim of the present invention is to provide an extrusion apparatus able to carry out an effective extrusion of plastic material having a relatively high content of humidity, higher than the content of humidity compatible with extrusion apparatuses of a known type.
  • an apparatus for extrusion of plastic material comprising: a supply hopper for supply of the plastic material; an extrusion head; and a first conveyor for fluidifying, compressing, heating, and feeding the plastic material in a direction of advance from the supply hopper to the extrusion head; the extrusion apparatus being characterized in that it comprises auxiliary channels that set the first conveyor in communication with the supply hopper for conveying the vapour generated during heating of the plastic material from the first conveyor to the supply hopper.
  • the auxiliary channels that connect the first conveyor to the supply hopper enable release into the atmosphere of the vapour that has developed as a result of heating and compression performed during advance of the plastic material along the first conveyor.
  • the extrusion apparatus carries out extrusion of the plastic material and simultaneously drying of the plastic material before the latter reaches the extrusion head.
  • the present invention moreover regards a method for extrusion of plastic material.
  • a method for extrusion of plastic material comprising the steps of fluidifying, compressing, heating, and feeding in a direction of advance the plastic material in a first conveyor from a supply hopper to an extrusion head; the method being characterized in that the vapour developed in the step of heating of the plastic material is conveyed from the first conveyor to the supply hopper through auxiliary channels .
  • Figure 1 is a partially cross-sectional view in side elevation, with parts removed for reasons of clarity, of the extrusion apparatus forming the subject of the present invention
  • Figure 2 is a view in side elevation at an enlarged scale, with parts in cross-sectional view, parts removed for reasons of clarity, and exploded parts, of the extrusion apparatus of Figure 1;
  • the reference number 1 designates as a whole an apparatus for extrusion of plastic material.
  • the extrusion apparatus 1 extends prevalently in a direction of advance D and comprises: a supply hopper 2 for supply of plastic material preferably in flakes; an extrusion head 3; a screw conveyor 4, extending between the supply hopper 2 and the extrusion head 3 in the direction of advance D; and a recirculation screw conveyor 5, which connects an intermediate part of the screw conveyor 4 and the supply hopper 2.
  • the supply hopper 2 is substantially defined by a cylindrical wall 6, which is joined to the screw conveyor 4 for introducing directly the flaked plastic material into the screw conveyor 4 in a free, i.e., non-forced, way. Consequently, the supply hopper 2 communicates directly with the surrounding environment .
  • the extrusion head 3 is set at the opposite end of the screw conveyor 4 with respect to the supply hopper 2 and is represented schematically in Figure 1.
  • the extrusion head 3 is built according to known constructional characteristics that are not illustrated in the attached plates of drawings, nor are they described herein.
  • the screw conveyor 4 extends between the supply hopper 2 and the extrusion head 3 along an axis Al parallel to the direction of advance D.
  • the screw conveyor 4 comprises: a duct 7, and a screw 8, which can turn within the duct 7 about the axis Al; and an electric motor 9 and a motor reducer 10 for rotating the screw 8 about the axis Al .
  • the duct 7 is heated and comprises a pipe 11 having a maximum diameter Dl, and a pipe 12, which has a diameter D2 smaller than the diameter Dl and a length sensibly greater than the length of the pipe 11 in the direction of advance D.
  • the pipes 11 and 12 are aligned along the axis Al and are connected to one another by a flange fixed with screws .
  • the pipe 11 has in succession in the direction of advance D a cylindrical seat 13 of diameter Dl, and a seat shaped like a truncated cone 14 converging towards the diameter D2 in the direction of advance D.
  • the pipe 12 has a cylindrical seat 15 of diameter D2.
  • the seat shaped like a truncated cone 14 connects the cylindrical seat 13 of diameter Dl to the cylindrical seat 15 of diameter D2 and has three longitudinal rectilinear ribs 16 (just two ribs 16 being illustrated in Figure 2) uniformly distributed about the axis Al and converging from the diameter Dl to the diameter D2.
  • the screw 8 has the shape of a truncated cone corresponding to the seat shaped like a truncated cone 14 so as to fit with a very small play into the ribs 16.
  • the seat shaped like a truncated cone 14 has, between each pair of adjacent ribs 16, an expansion chamber 17, delimited by a vaulted surface 18 and by the ribs 16.
  • Indicated with dashed lines in Figures 3, 4 and 5 are circles Cl, C2 and C3 , respectively, which define the encumbrance of the screw 8 rotating about the axis Al.
  • the height (measured in a radial direction with reference to the axis Al) of the surfaces 18 and of the ribs 16 with respect to the circles Cl, C2 and C3 reduces progressively as the seat shaped like a truncated cone 14 converges in the direction of the pipe 12.
  • Each expansion chamber 17 enables the vapour generated by heating of the screw conveyor 4 to reach the supply hopper 2 and to be released into the atmosphere.
  • the expansion chambers 17 define auxiliary channels for conveying the vapour in a direction substantially opposite to the direction of advance D of the plastic material . Evacuation of the vapour is facilitated by the fact that the vapour is able to pass through the plastic material, which in the seat shaped like a truncated cone 14 has started the fluidification phase, but still has spaces left free between the flakes.
  • the ribs 16 and the expansion chambers 17 are made in the duct 7 itself by machining, in particular in the pipe 11.
  • the screw 8 comprises a shaft 19, and a helical ridge 20, which extends from the shaft 19.
  • the shaft 19 extends along the axis Al and has in succession in the direction of advance D: a cylindrical section 21; a section shaped like a convergent truncated cone 22; a section shaped like a divergent truncated cone 23; a section shaped like a convergent truncated cone 24; a cylindrical section 25; and a section shaped like a divergent truncated cone 26.
  • the cylindrical section 21 is set in the cylindrical seat 13, the section shaped like a converging truncated cone 22 is set in the seat shaped like a truncated cone 14, whilst the sections shaped like a truncated cone 23, 24, and 26 and the cylindrical section 25 are set within the cylindrical seat 15.
  • the section shaped like a truncated cone 22 has a conicity smaller than the conicity of the seat 14 and, consequently, the radial dimension of the helical ridge 20 reduces progressively in the direction of advance D. In this way, the plastic material is compressed along the section shaped like a convergent truncated cone 22.
  • the variations in diameter of the shaft 19 cause a reduction in the effective section of passage or an enlargement in the effective section of passage.
  • the plastic material is compressed along the sections shaped like a divergent truncated cone 23 and 26 and is expanded along the section shaped like a convergent truncated cone 24.
  • the duct 7 comprises electrical resistors 27, schematically illustrated in Figure 1, for heating the plastic material during advance thereof in the screw conveyor 4 according to known modalities .
  • the screw conveyor 4 is equipped with: a heat exchanger 28 set around the pipe 11 in a position corresponding to the supply hopper 2 for cooling the plastic material contained in the cylindrical seat 13 ; and a drain pipe 29 for evacuating the water that may possibly have accumulated and condensed in the cylindrical seat 13.
  • the recirculation screw conveyor 5 extends between an opening 30 provided along the pipe 12 and an opening 31 made in the wall 6 of the supply hopper 2 and comprises: a duct 32 extending along an axis A2 ; a screw 33, which can be turned about the axis A2 ; and an electric motor 34 and a motor reducer 35, connected to the electric motor 34 and to the screw 33.
  • the duct 32 has a seat 36 of constant diameter D3
  • the screw 33 comprises a shaft 37 of constant diameter and a helical ridge 38 of constant pitch.
  • the duct 32 has an end flange 39 fixed to the supply hopper 2 and is fixed to the pipe 12 by means of a manifold 40 set around the pipe 12 and provided with a seat for housing the screw conveyor 5 so as to set the cylindrical seat 15 in direct communication with the cylindrical seat 36.
  • the opening 30 is set in a position corresponding to the cylindrical section 25 of the shaft 19. In this area, the plastic material previously compressed expands on account of widening of the effective section of passage and penetrates into the seat 36 and is supplied by the screw conveyor 5 to the supply hopper 2 in which it is mixed to the flakes of plastic material supplied through the supply hopper 2 itself.
  • the screw conveyor 5 is equipped with electrical resistors 27 for preventing solidification of the plastic material and condensation of the vapour, and basically defines an auxiliary channel, through which the vapour developed owing to heating of the screw conveyor 4 is brought back to the supply hopper 2 and released into the atmosphere.
  • the extrusion apparatus 1 functions in the way described in what follows.
  • the flakes of recycled plastic material not subjected to centrifugation and thickening and, hence, containing a weight percentage of water higher than 0.5 wt%, are supplied to the supply hopper 2.
  • the screw conveyor 4 feeds the flakes of plastic material in the direction of advance D towards the extrusion head 3.
  • the plastic material is heated by the electrical resistors 27 and compressed by the screw 8 so as to transform the flakes of plastic material progressively into a pasty fluid and feed a flow Ql of plastic material to the extrusion head.
  • the first step of compression and heating of the plastic material is carried out in the seat shaped like a truncated cone 14.
  • heating and compression bring about production of water vapour, which is able to ascend the screw conveyor 4 in a direction substantially opposite to the direction of advance D thanks to the expansion chambers 17, which define auxiliary evacuation channels made directly in the screw conveyor 4.
  • the vapour reaches the cylindrical seat 13 and, in part, is released into the atmosphere through the supply hopper 2 and, in part, condenses to form water, which is evacuated through the drain pipe 29.
  • the plastic material is heated and further compressed along the section 23 shaped like a truncated cone of the shaft 19 and expands along the section shaped like a converging truncated cone 24 and along the cylindrical section 25.
  • the plastic material of the structure is transformed progressively from the solid structure in the form of flakes into a pasty fluid.
  • the plastic material releases further vapour.
  • the plastic material by expanding, in part, penetrates into the seat 36 of the screw conveyor 5 and is supplied by the screw conveyor 5 to the supply hopper 2 in which part of the vapour is released into the atmosphere and, in part, is condensed by the heat exchanger 28. Remixing of the recycled plastic material with the flakes supplied to the supply hopper 2 accelerates heating of the flakes and favours release of the vapour trapped in the plastic material itself.
  • the screw conveyor 5 has a flow Q2 of plastic material comprised between 5% and 20% of the flow Ql. Consequently, along the portion of the first screw conveyor 4 comprised between the supply hopper 2 and the opening 30, a flow of plastic material is fed equal to the sum of the flows Ql and Q2.
  • the heat exchanger 28 has the function of preventing an excessive heating of the flakes in the supply step and of preventing any possible seizing. In addition, the heat exchanger 28 enables condensation of possible vapour that has remained trapped by the plastic material. The condensed vapour is evacuated through the drainage channel 29.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
  • Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
  • Extrusion Moulding Of Plastics Or The Like (AREA)

Abstract

L'invention concerne un appareil (1) d'extrusion de matériau plastique recyclé à haute teneur en humidité résiduelle, qui est équipé : d'une trémie (2) qui alimente en matériau plastique; d'une tête d'extrusion (3); d'un premier transporteur (4) pour fluidifier, comprimer, chauffer le matériau plastique et le fournir dans la direction d'avancement (D) à partir de la trémie d'alimentation (2) à la tête d'extrusion (3); et de canaux auxiliaires (5; 17), qui mettent le premier transporteur en communication avec la trémie d'alimentation (2) pour transporter la vapeur produite pendant le chauffage du matériau plastique du premier transporteur (4) à la trémie d'alimentation (2).
PCT/IB2007/002729 2006-09-21 2007-09-21 Appareil et procédé d'extrusion de matériau plastique Ceased WO2008035185A2 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
ITMI2006A001798 2006-09-21
IT001798A ITMI20061798A1 (it) 2006-09-21 2006-09-21 Apparecchiatura e metodo di estrusione di materiale plastico

Publications (2)

Publication Number Publication Date
WO2008035185A2 true WO2008035185A2 (fr) 2008-03-27
WO2008035185A3 WO2008035185A3 (fr) 2008-07-17

Family

ID=38963075

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IB2007/002729 Ceased WO2008035185A2 (fr) 2006-09-21 2007-09-21 Appareil et procédé d'extrusion de matériau plastique

Country Status (2)

Country Link
IT (1) ITMI20061798A1 (fr)
WO (1) WO2008035185A2 (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115847906A (zh) * 2022-11-29 2023-03-28 萍乡市路盟环保新材料研发中心有限公司 一种球形催化剂的挤出成型头

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2235023C3 (de) * 1972-07-17 1975-05-07 Nordenia-Kunststoffe Peter Mager Kg, 2841 Steinfeld Vorrichtung zum Vorwärmen pulverförmiger oder körniger thermoplastischer Kunststoffe
US4636085A (en) * 1982-03-16 1987-01-13 Mapro Inc. Apparatus for removing volatiles from plastic materials delivered to an extrusion or injection molding machine
DE3485203D1 (de) * 1983-07-22 1991-11-28 Mapro Inc Verfahren und vorrichtung zur beseitigung von feuchtigkeit und fluechtigen bestandteilen aus aus partikeln bestehendem plastikformwerkstoff.

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115847906A (zh) * 2022-11-29 2023-03-28 萍乡市路盟环保新材料研发中心有限公司 一种球形催化剂的挤出成型头

Also Published As

Publication number Publication date
WO2008035185A3 (fr) 2008-07-17
ITMI20061798A1 (it) 2008-03-22

Similar Documents

Publication Publication Date Title
CN1123437C (zh) 同方向旋转双螺杆挤出机的高熔点树脂脱水方法
JP7144513B2 (ja) バルク形態の熱機械的変形可能材料の押出装置および押出方法、ならびにコンパクト・スクリュー押出機
US6619575B1 (en) Apparatus for continuously recycling synthetic material, preferably polymers
CA2390199C (fr) Appareil de traitement preliminaire et de plastification ou d'agglomeration subsequente de matieres plastiques synthetiques
CA2524331C (fr) Dispositif de traitement d'un materiau plastique en vue de son recyclage
MX2014004450A (es) Dispositivo para procesar material plastico.
JP2014530134A (ja) プラスチック材料処理装置
WO2008035185A2 (fr) Appareil et procédé d'extrusion de matériau plastique
CN207310597U (zh) 一种提高压榨效率的螺旋压榨机
CN100556561C (zh) 聚氨酯硬泡沫废弃物无害化处理方法
CN109719924A (zh) 一种发泡废料低温裂泡挤出机及挤出方法
JP3597070B2 (ja) 耐衝撃性熱可塑性樹脂の製造装置およびその方法
CN101259747A (zh) 一种基于单螺杆挤出的一步法木塑复合材料挤出成型设备
US12390975B2 (en) Extruder
CN202528414U (zh) 三阶式高效塑化过滤排气塑料挤出系统
JP3895103B2 (ja) 廃棄プラスチックの脱塩素処理装置
JP3892366B2 (ja) 廃プラスチックの処理装置
KR101627720B1 (ko) 폐 가교 폴리올레핀 수지의 연속식 재생 장치
KR101204050B1 (ko) 펠릿성형 및 자연건조를 이용한 폐석분의 재활용 처리방법 및 폐석분 재활용 처리장치
CN109049398A (zh) 一种新型塑料voc脱除装置
KR101171966B1 (ko) 폐비닐 압축 성형방법
CN1541156A (zh) 制模方法和设备
JP5617770B2 (ja) 高分子化合物の処理方法及び装置
KR100538478B1 (ko) 발포수지 감용기
JP2001058346A (ja) ベント式単軸スクリュ押出機

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 07825148

Country of ref document: EP

Kind code of ref document: A2

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 07825148

Country of ref document: EP

Kind code of ref document: A2