Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/02—Separating plastics from other materials
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/04—Disintegrating plastics, e.g. by milling
  • B29B17/0412—Disintegrating plastics, e.g. by milling to large particles, e.g. beads, granules, flakes, slices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/02—Separating plastics from other materials
  • B29B2017/0203—Separating plastics from plastics
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/02—Separating plastics from other materials
  • B29B2017/0213—Specific separating techniques
  • B29B2017/0217—Mechanical separating techniques; devices therefor
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/02—Separating plastics from other materials
  • B29B2017/0213—Specific separating techniques
  • B29B2017/0217—Mechanical separating techniques; devices therefor
  • B29B2017/0227—Vibratory or shaking tables
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/02—Separating plastics from other materials
  • B29B2017/0213—Specific separating techniques
  • B29B2017/0217—Mechanical separating techniques; devices therefor
  • B29B2017/0231—Centrifugating, cyclones
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/04—Disintegrating plastics, e.g. by milling
  • B29B2017/0424—Specific disintegrating techniques; devices therefor
  • B29B2017/0476—Cutting or tearing members, e.g. spiked or toothed cylinders or intermeshing rollers
• • 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
  • B29K2023/00—Use of polyalkenes or derivatives thereof as moulding material
  • B29K2023/04—Polymers of ethylene
  • B29K2023/06—PE, i.e. polyethylene
• • 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
  • B29K2067/00—Use of polyesters or derivatives thereof, as moulding material
  • B29K2067/003—PET, i.e. poylethylene terephthalate
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29L—INDEXING SCHEME ASSOCIATED WITH SUBCLASS B29C, RELATING TO PARTICULAR ARTICLES
  • B29L2009/00—Layered products
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
  • Y02W30/00—Technologies for solid waste management
  • Y02W30/50—Reuse, recycling or recovery technologies
  • Y02W30/62—Plastics recycling; Rubber recycling
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
  • Y02W30/00—Technologies for solid waste management
  • Y02W30/50—Reuse, recycling or recovery technologies
  • Y02W30/80—Packaging reuse or recycling, e.g. of multilayer packaging

Definitions

• the present invention relates to a system and a method for separating the layers of multilayer plastics.
• Multilayer plastics are currently used in many activities and fields such as agriculture, industry and packaging. As awareness of the protection of the environment grows, there is a general shift towards a comprehensive management of the life of the product, including its recycling and the recovery of its useful parts, allowing a later use of the recovered materials for new products and a reduction of waste, pollution and costs.
• the methods comprise a first stage to weaken the bond between layers, that is, the adhesive, and a second stage to physically and / or chemically separate the layers.
• the first stage requires the direct heating of the multilayer plastic fragments. These fragments are obtained by a previous stage of shredding of the articles to reduce the size of the objects to a size suitable for processing by the recycling method.
• the second stage usually requires a chemical composition that reacts with some part of the multilayer plastic fragments, dissolving the adhesive or some of the layers of the multilayer plastic fragments.
• the second stage may also include, alternatively or jointly with the chemical separation, a physical separation of the layers of the multilayer plastic fragments by crushing, grinding, polishing, cutting and abrasive substances.
• a subsequent drying stage is commonly needed to remove traces of water and any remaining fluid from the second stage.
• the object of the invention is to provide a system and method for separating the layers of multilayer plastics that solve the aforementioned drawbacks.
• the invention provides a system for separating the layers of multilayer plastics, comprising: - an inlet hopper for the introduction of the multilayer plastic fragments,
• a mechanical separation unit located next to! discharge tank
• a mechanical classification unit located next to the mechanical separation unit, which also comprises a valve between the inlet hopper and the vessel, a discharge valve between the vessel and the discharge tank, a recovery valve between the tank discharge and mechanical recompression machine, a valve between the discharge tank and the pump and an inlet control valve between the boiler and the vessel
• the invention also provides a method for separating the layers of multilayer plastics, and comprising at least a first layer and a second layer of different plastics, and using the system of the invention, the method comprising the following
• Figure 2 shows a partial schematic view of the installation used to separate the layers of muiticap plastics of the invention.
• Figure 3 shows an embodiment of a mechanical separation unit used in the system to separate the layers of muiticap plastics of the invention.
• Muiticapa plastics have, at least, a first layer and a second layer of different plastics, being able to comprise more layers of other plastics.
• the bonding of the plastic layers is usually an adhesive, placed between two layers of plastic.
• vacuum refers to both the absolute vacuum, in which the absolute pressure is zero, and the relative vacuum, in which the pressure is less than another reference pressure.
• it is explicitly added by adding “absolute” or “relative” respectively.
• Multilayer plastics are shredded into multilayer plastic fragments by any mechanical procedure. In one embodiment, the final size of the fragments, measured in their greatest length, is not less than 10 mm.
• the superheated steam causes a thermal shock, which does not necessarily heat the entire particle to a certain temperature, and a mechanical shock, due to the abrupt change in pressure to which the plastic layers are subjected to passing from atmospheric pressure to working pressure, allowing the successful separation of the layers in the mechanical separation stage.
• the vapor puts pressure on the fragments, weakening and breaking the chemical bonds between the layers. Since only steam is heated, energy is saved, and no chemicals are needed.
• the temperature and pressure conditions inside the vessel and the discharge tank are kept constant by the boiler, valves, pumps or other control means. In this way, the loss of energy is avoided and productivity is increased, because the vessel and the tank are permanently prepared to receive multilayer plastic fragments.
• the vessel may be connected to a discharge tank through a discharge valve or other control means.
• the pressurization and vacuum cycles consist of the introduction of the multilayer plastic fragments into the vessel, which already contains steam superheated at the temperature and at the predetermined pressure according to the types of plastics to be treated, through a valve or other means of control, and keep them inside for a predetermined time according to the types of plastic to be treated.
• the multilayer plastic fragments are transferred to the discharge tank, which is about predetermined temperature and pressure conditions according to the types of plastics to be treated and less than the pressure and temperature conditions inside the vessel, and are kept inside for a predetermined time according to the types of plastic to be treated.
• pressurization and vacuum cycles can be executed once or several times depending on the types of plastic and other properties of the multilayer plastic fragments, returning, through valves and other control means, the multilayer plastic fragments of the discharge tank to the vessel.
• the application in the pressure and high temperature vessel is simultaneous thanks to the action of superheated steam.
• the application in the discharge tank of a vacuum and a reduced temperature is simultaneous.
• This type of pressurization and vacuum cycle increases the pressure difference that the multilayer plastic fragments support, compressing and decompressing the layers together, producing tensile, compression and shear forces between them, further weakening the bond between the layers.
• Another advantage of this pressurization and vacuum cycle is that the layers are dried during the vacuum phase, eliminating the subsequent drying stage.
• a valve is provided that communicates the vessel and the boiler and is managed by a control system.
• the control system manages the opening of the valve to allow steam to enter the vessel and thus keep constant the predetermined conditions of pressure and temperature inside the vessel.
• a valve and a pump are provided, the valve connects the pump and the discharge tank; The pump maintains the predetermined pressure and temperature conditions inside, extracting fluid from inside the discharge tank.
• the fluid extracted by the pump from the discharge tank can be recompressed and used in other parts of the method.
• the invention comprises a stage of mechanical separation of the plastic layers from the fragments to obtain monolayer plastic fragments, which are consequently also monocomponent fragments.
• the unions have weakened enough to allow mechanical separation of the layers. This separation includes the actions of cutting, brushing, polishing and rubbing the fragments.
• fragments Once the fragments have been separated into monolayer fragments, they are introduced into a mechanical layer separation unit, where they are classified by their composition taking advantage of the different densities of the plastics, placing the monolayer fragments in a controlled air flow.
• one of the layers of the muiticap plastics is polyethylene terephthalate (PEI) and another of the layers is polyethylene (PE).
• PEI polyethylene terephthalate
• PE polyethylene
• the method is suitable for separating layers of any other plastic materials.
• the vessel (1) comprises internal pressure and temperature sensors, which provide data on these quantities to a control system.
• This control system controls these variables by acting on control valves, which are the steam inlet control valve (10), the vessel discharge valve (2) (1) and the valve
• the composition of superheated steam is water.
• the boiler (3) produces water vapor by any heating method (for example, electrical resistance, microwave).
• the boiler (3) is controlled by the control system to produce a superheated steam of the characteristics required for the types of plastic to be treated.
• the boiler (3) is turned on, which produces superheated steam.
• the valve (10) opens to allow the passage of superheated water vapor to the vessel (1), until reaching predetermined pressure and temperature conditions (pressure: 1 -12 bar; temperature: 100-191, 12 e C ). These conditions remain constant during the application of the separation method to all the amount of fragments to be treated.
• the discharge tank (4) is fluidly connected to a pump (5) through a valve
• the pump (5) maintains constant relative vacuum conditions of -0.7 bar at 0.1 bar (with respect to ambient pressure) inside the discharge tank (4), which is kept during the apiication of! method of separation to all the amount of fragments to be treated.
• the temperature in the discharge tank (4) will be between 15-25 9 C.
• the pressure and temperature conditions in the vessel (1) and in the discharge tank (4) are the predetermined ones, after obtaining the fragments of multilayer plastics of a size greater than 10 mm from multilayer plastics, they are introduced into the vessel (1) by an inlet hopper (9) opening a valve (20), located at the outlet of the inlet hopper (9).
• the fragments are maintained for a predetermined time in the vessel (1), where they suffer the action of high pressure and high temperature of superheated water vapor. If the layers are made with PEI and PE, this time is preferably between 10 seconds and 60 seconds.
• the vessel discharge valve (2) opens (1), and the fragments pass to the discharge tank (4), where they are kept for a predetermined time (between 1 minute and 5 minutes), where they suffer the relative emptiness and the inferior femperafura of its inferior. If the layers are made with PET and PE, this time is preferably 5 minutes. After the predetermined time has elapsed under these conditions of relative vacuum, the fragments are transferred to a mechanical separation unit (6).
• the water vapor that had entered the discharge tank (4) is extracted through a recovery valve (1 1), which connects it to a mechanical recompression machine (8).
• the resulting condensed water is filtered and reintroduced into the boiler (3).
• the fragments are transferred to a mechanical separation unit (6).
• the mechanical separation unit (6) shown in Figure 3, comprises means for polishing, cutting, brushing and rubbing the multilayer plastic fragments together, to obtain monolayer fragments and composed of a single type of plastic.
• These means are one or several drums (16) that rotate on an axis within a chamber (17).
• Drums (16) comprise a rough surface that peels and polishes the fragments.
• Other drums (16) comprise a surface covered with metal bars placed perpendicularly to the surface of the drum. The cut, therefore, occurs without using blades or any other sharp element.
• the drums (16) are arranged in a straight line, one after the other, leaving a small space (19) between the closest point of its surface to one of the chamber surfaces (17) and this chamber surface (17), preferably a distance of 0.8 mm, to promote friction between the fragments and between the fragments and the surfaces of the drums (16).
• This space (19) is adjustable by the movement of the rollers towards or from the surface of the chamber (17), or by the movement of the surface of the chamber (17) closest to the drums (16) towards or from these drums (16).
• the row of drums (16) is arranged at an angle close to 60 ° to the ground.
• the drums (16) comprise a barrier (18) placed between every two drums (16), the drums (16) forming, the wall of the chamber (17) closest to these and the barriers (18) a separation volume ( 13) only opened by an inlet hopper (12), located at the upper end of the chamber (17) and by an outlet hopper (14), located at the lower end of the chamber (17), so that ios fragments only move by gravity from the inlet hopper (12) through the volume (13), preventing its passage to another chamber volume (17)
• the inlet hopper (12) comprises a wall (15) that directs the fragments towards the separation volume (13).
• the fragments are introduced into the separation unit (6) by the input hopper (12), and fall by gravity through the chamber (17), specifically the separation volume (13), receiving the action of the drums ( 16). Throughout their fall, the layers separate from each other and the remaining moisture is eliminated thanks to their agitation. Finally, already separated into monolayer fragments, they exit through the outlet hopper (14).
• the output hopper (14) is connected to the mechanical classification unit (7).
• the mechanical classification unit (7) comprises a vibrating table, a vacuum cleaner and a cyclone. The particles are transferred to the table.
• the action of the vibrating table combined with a regulated aspiration of the vacuum cleaner, separates the fragments according to their density, aspirating the lighter phase, leaving the heavier phase on the table, thus separating the fragments according to their composition.

Landscapes

• Engineering & Computer Science (AREA)
• Environmental & Geological Engineering (AREA)
• Mechanical Engineering (AREA)
• Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)
• Processing And Handling Of Plastics And Other Materials For Molding In General (AREA)
• Processing Of Solid Wastes (AREA)
• Disintegrating Or Milling (AREA)

Priority Applications (21)

Applications Claiming Priority (1)

Publications (1)

Family

ID=69231459

Family Applications (1)

Country Status (21)

Families Citing this family (2)

Citations (14)

Family Cites Families (6)

• 2018
  • 2018-08-01 CN CN201880096247.4A patent/CN112888541B/zh not_active Expired - Fee Related
  • 2018-08-01 HU HUE18928302A patent/HUE061073T2/hu unknown
  • 2018-08-01 AU AU2018434968A patent/AU2018434968B9/en active Active
  • 2018-08-01 RS RS20230033A patent/RS63974B1/sr unknown
  • 2018-08-01 EP EP18928302.1A patent/EP3831566B1/en active Active
  • 2018-08-01 MX MX2021001275A patent/MX2021001275A/es unknown
  • 2018-08-01 HR HRP20230051TT patent/HRP20230051T1/hr unknown
  • 2018-08-01 ES ES18928302T patent/ES2936236T3/es active Active
  • 2018-08-01 SI SI201830848T patent/SI3831566T1/sl unknown
  • 2018-08-01 DK DK18928302.1T patent/DK3831566T3/da active
  • 2018-08-01 JP JP2021529528A patent/JP7268920B2/ja active Active
  • 2018-08-01 MA MA53303A patent/MA53303B1/fr unknown
  • 2018-08-01 IL IL280561A patent/IL280561B2/en unknown
  • 2018-08-01 US US17/264,718 patent/US11858174B2/en active Active
  • 2018-08-01 BR BR112021001779-8A patent/BR112021001779B1/pt active IP Right Grant
  • 2018-08-01 PT PT189283021T patent/PT3831566T/pt unknown
  • 2018-08-01 CA CA3108394A patent/CA3108394A1/en active Pending
  • 2018-08-01 PL PL18928302.1T patent/PL3831566T3/pl unknown
  • 2018-08-01 FI FIEP18928302.1T patent/FI3831566T3/fi active
  • 2018-08-01 WO PCT/ES2018/070541 patent/WO2020025836A1/es not_active Ceased
• 2021
  • 2021-03-01 ZA ZA2021/01407A patent/ZA202101407B/en unknown

Patent Citations (14)

Non-Patent Citations (2)

Also Published As

Similar Documents

Legal Events