EP0530501B1 - Method and device for glue coating of particles - Google Patents

Method and device for glue coating of particles Download PDF

Info

Publication number
EP0530501B1
EP0530501B1 EP92112993A EP92112993A EP0530501B1 EP 0530501 B1 EP0530501 B1 EP 0530501B1 EP 92112993 A EP92112993 A EP 92112993A EP 92112993 A EP92112993 A EP 92112993A EP 0530501 B1 EP0530501 B1 EP 0530501B1
Authority
EP
European Patent Office
Prior art keywords
glue
particles
pipe
electrostatic charge
charge
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.)
Expired - Lifetime
Application number
EP92112993A
Other languages
German (de)
French (fr)
Other versions
EP0530501A1 (en
Inventor
N. Lennart Eriksson
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.)
Valmet AB
Original Assignee
Sunds Defibrator Industries AB
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 Sunds Defibrator Industries AB filed Critical Sunds Defibrator Industries AB
Publication of EP0530501A1 publication Critical patent/EP0530501A1/en
Application granted granted Critical
Publication of EP0530501B1 publication Critical patent/EP0530501B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
    • B27N—MANUFACTURE BY DRY PROCESSES OF ARTICLES, WITH OR WITHOUT ORGANIC BINDING AGENTS, MADE FROM PARTICLES OR FIBRES CONSISTING OF WOOD OR OTHER LIGNOCELLULOSIC OR LIKE ORGANIC MATERIAL
    • B27N1/00—Pretreatment of moulding material
    • B27N1/02—Mixing the material with binding agent

Definitions

  • This invention refers to a method and a device for the glue coating of particles, primarily of cellulose material such as fibres and chips, in connection with the manufacture of e.g. fiber board according to the dry method, so-called MDF (Medium Density Fiberboard), dry-formed paper and particle board, according to the preambles of claims 1 and 7, respectively.
  • MDF Medium Density Fiberboard
  • the admixture of glue has the object to improve the bond between the particles in order to achieve a strong fibre, chip or paper product.
  • the glue is of the heat-curing type.
  • For fibre and chip products normally urea formaldehyde resin and phenol resin are used.
  • For paper products other binding agents are used, for example latex.
  • blow line glue coating is applied for glue coating.
  • the fibres are produced in a pulper, whereafter the fibres, together with the steam generated in the pulper and a small amount of water, are transported through a line to a drier.
  • the speed in this blow line is 30-300 m/s. Due to the high turbulence in the blow line, the liquid glue injected into the blow line at high pressure is atomized and adheres to the fibres.
  • Such a method and corresponding apparatus is known from US-A-4 510 184 on which the preambles of claims 1 and 7 are based.
  • the present invention solves the aforesaid problem and offers additional advantages.
  • the invention implies, that prior to their mixture a different electrostatic charge is applied to the glue and particles, so that a strong attractive force arises between the same.
  • the characterizing features of the invention are defined in the attached claims.
  • the amount of particles normally being greater than the amount of glue it is particularly suitable to apply a controlled and adjustable charge on the glue.
  • the particles can be charged during their transport before the place of mixture.
  • the glue can be in liquid or powder state and be of the type stated above.
  • the charging of the glue can be effected by means of an external current source or by friction charge.
  • the latter can be used with powdered glue, and the glue is charged by friction against the transport line, which preferably is a plastic line.
  • a suitable charge is 5000 - 100 000 V.
  • the method according to the invention generally, yields a greater flexibility in choosing the place in the process where the glue coating can take place.
  • liquid glue according to the invention contrary to conventional blow line glue coating, renders it possible to add the glue in a position where the temperature is lower than in the blow line, whereby the glue is less cured and, consequently, the glue consumption is smaller.
  • the admixture of dry glue according to the invention implies, that the total energy consumption can be reduced because no energy need to be supplied for evaporating the water contained in the liquid glue. This is an advantage, in spite of the fact that the glue is more expensive because it may be necessary at the manufacture of the glue to dry the glue from e.g. 60% dry matter content to 90% dry matter content. A saving of energy of up to 10% compared with conventional blow line glue coating can be obtained. This corresponds also to a 10% reduction in the glue of the drier or to a 10% higher capacity of the drier installed.
  • Particles in the form of fibres are transported through a pipe 1 at a flow rate of 25-40 m/s.
  • the glue is supplied through a feed line 2 to the fibre material in the pipe 1 in such a way, that the glue meets the fibre flow.
  • the desired charge is applied to the glue by means of an external controllable current source 3.
  • the injection of the glue preferably takes place immediately before a bend of the pipe 1, in order to render possible a simple arrangement of the necessary equipment as shown in the Figure.
  • the charging of the glue can be effected by so-called friction charge.
  • Such a charging can be brought about by air transport of the glue in a plastic line where the charging can be controlled by the flow rate and the line length.
  • the glue supply can be controlled in a conventional way.
  • portion 4 of the pipe 1,where the glue is injected may be suitable to form portion 4 of the pipe 1,where the glue is injected, of an insulating material, such as plastic, porcelain, wood or the like whereby the charge of the glue and, respectively, particles is not conducted away.
  • an insulating material such as plastic, porcelain, wood or the like whereby the charge of the glue and, respectively, particles is not conducted away.

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Wood Science & Technology (AREA)
  • Forests & Forestry (AREA)
  • Application Of Or Painting With Fluid Materials (AREA)
  • Manufacturing Of Micro-Capsules (AREA)
  • Dry Formation Of Fiberboard And The Like (AREA)
  • Paper (AREA)
  • Adhesives Or Adhesive Processes (AREA)

Abstract

A method and a device for glue coating primarily cellulose-containing material, in connection with the manufacture of fiber board, particle board, dry-formed paper and the like. The glue is supplied through a supply line (2) to a flow of particles in a pipe (1). Prior to the mixing, a different electrostatic charge is applied in a controlled way on the glue and particles, so that a strong attractive force arises between glue and particles. <IMAGE>

Description

  • This invention refers to a method and a device for the glue coating of particles, primarily of cellulose material such as fibres and chips, in connection with the manufacture of e.g. fiber board according to the dry method, so-called MDF (Medium Density Fiberboard), dry-formed paper and particle board, according to the preambles of claims 1 and 7, respectively.
  • The admixture of glue has the object to improve the bond between the particles in order to achieve a strong fibre, chip or paper product. The glue is of the heat-curing type. For fibre and chip products normally urea formaldehyde resin and phenol resin are used. For paper products other binding agents are used, for example latex.
  • At the manufacture of particle board, and in certain cases of MDF, so-called mechanical glue mixers are used at present (see DE-B-1 908 957). These mixers consist in principle of a trum comprising a rotor member. Particles and glue are supplied to the drum where the glue is sprayed in form of a suspension over the particles. For effecting a good distribution of the glue, the mixture of particles and glue is subjected to heavy stirring by the rotor.
  • At the manufacture of MDF, another method, so-called blow line glue coating, is applied for glue coating. The fibres are produced in a pulper, whereafter the fibres, together with the steam generated in the pulper and a small amount of water, are transported through a line to a drier. The speed in this blow line is 30-300 m/s. Due to the high turbulence in the blow line, the liquid glue injected into the blow line at high pressure is atomized and adheres to the fibres. Such a method and corresponding apparatus is known from US-A-4 510 184 on which the preambles of claims 1 and 7 are based.
  • At these known methods, the use of mechanical glue mixers results in a glue consumption which is lower than at blow line glue coating. The disadvantage of mechanical glue mixers, however, is that it is not possible to distribute the glue uniformly on the fibres. On some fibres the amount of glue adhering thereon is so great, that lumps are formed. These lumps appear as dark-coloured spots on the finished product.
  • The present invention solves the aforesaid problem and offers additional advantages. The invention implies, that prior to their mixture a different electrostatic charge is applied to the glue and particles, so that a strong attractive force arises between the same. The characterizing features of the invention are defined in the attached claims.
  • The amount of particles normally being greater than the amount of glue, it is particularly suitable to apply a controlled and adjustable charge on the glue. The particles can be charged during their transport before the place of mixture.
  • The glue can be in liquid or powder state and be of the type stated above. The charging of the glue can be effected by means of an external current source or by friction charge. The latter can be used with powdered glue, and the glue is charged by friction against the transport line, which preferably is a plastic line. A suitable charge is 5000 - 100 000 V.
  • The method according to the invention, generally, yields a greater flexibility in choosing the place in the process where the glue coating can take place.
  • The admixture of liquid glue according to the invention, contrary to conventional blow line glue coating, renders it possible to add the glue in a position where the temperature is lower than in the blow line, whereby the glue is less cured and, consequently, the glue consumption is smaller.
  • The admixture of dry glue according to the invention implies, that the total energy consumption can be reduced because no energy need to be supplied for evaporating the water contained in the liquid glue. This is an advantage, in spite of the fact that the glue is more expensive because it may be necessary at the manufacture of the glue to dry the glue from e.g. 60% dry matter content to 90% dry matter content. A saving of energy of up to 10% compared with conventional blow line glue coating can be obtained. This corresponds also to a 10% reduction in the glue of the drier or to a 10% higher capacity of the drier installed.
  • The invention is described in greater detail in the following, with reference to an embodiment thereof shown in the accompanying drawing.
  • Particles in the form of fibres are transported through a pipe 1 at a flow rate of 25-40 m/s. The glue is supplied through a feed line 2 to the fibre material in the pipe 1 in such a way, that the glue meets the fibre flow. The desired charge is applied to the glue by means of an external controllable current source 3. The injection of the glue preferably takes place immediately before a bend of the pipe 1, in order to render possible a simple arrangement of the necessary equipment as shown in the Figure.
  • The charging of the glue, alternatively, can be effected by so-called friction charge. Such a charging can be brought about by air transport of the glue in a plastic line where the charging can be controlled by the flow rate and the line length.
  • The glue supply can be controlled in a conventional way.
  • It may be suitable to form portion 4 of the pipe 1,where the glue is injected, of an insulating material, such as plastic, porcelain, wood or the like whereby the charge of the glue and, respectively, particles is not conducted away.
  • The invention, of course, is not restricted to the embodiments set forth, but can be varied within the scope of the invention as claimed.

Claims (10)

  1. A method of glue coating particles, primarily of cellulose-containing material, in connection with the manufacture of fiber board, particle board, dry-formed paper and the like, comprising the supply of the glue directly into a flow of particles in a pipe, characterized in that prior to their mixture a different electrostatic charge is applied in a controlled way on the glue and particles, so that a strong attractive force arises between glue and particles.
  2. A method as defined in claim 1, characterized in that an electrostatic charge is applied on the glue by means of an external current source.
  3. A method as defined in claim 1, characterized in that an electrostatic charge is applied on the glue by means of friction in the supply line.
  4. A method as defined in any one of the preceding claims, characterized in that the glue is supplied so that it meets the particle flow in the pipe.
  5. A method as defined in any one of the preceding claims, characterized in that the electrostatic charge is 5 000-100 000 V.
  6. A method as defined in any one of the preceding claims, characterized in that the particle flow rate is 25-40 m/s.
  7. A device for size coating particles, primarily of cellulose-containing material, in connection with the manufacture of fiber board, particle board, dry-formed paper and the like, comprising a pipe (1) for transporting the particles and a supply line (2) for the glue connected to said pipe (1), for supply of the glue directly into the flow of particles in the pipe, characterized in that means are provided to apply an electrostatic charge on the glue in the glue supply line (2) which electrostatic charge is different from the charge of the particles.
  8. A device as defined in claim 7, characterized in that the electrostatic charging is effected by an external controllable current source (3).
  9. A device as defined in claim 7, characterized in that the electrostatic charging is effected by friction charging the glue in the supply line (2).
  10. A device as defined in the claims 7-9, characteized in that the portion (4) of the pipe (1) where the glue is supplied, is formed of a material which does not conduct away the charge of the glue and, respectively, particles.
EP92112993A 1991-09-05 1992-07-30 Method and device for glue coating of particles Expired - Lifetime EP0530501B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE9102549 1991-09-05
SE9102549A SE502518C2 (en) 1991-09-05 1991-09-05 Methods and apparatus for bonding particles

Publications (2)

Publication Number Publication Date
EP0530501A1 EP0530501A1 (en) 1993-03-10
EP0530501B1 true EP0530501B1 (en) 1995-11-02

Family

ID=20383626

Family Applications (1)

Application Number Title Priority Date Filing Date
EP92112993A Expired - Lifetime EP0530501B1 (en) 1991-09-05 1992-07-30 Method and device for glue coating of particles

Country Status (5)

Country Link
EP (1) EP0530501B1 (en)
AT (1) ATE129660T1 (en)
DE (1) DE69205772T2 (en)
ES (1) ES2079111T3 (en)
SE (1) SE502518C2 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
IT1296755B1 (en) * 1997-11-10 1999-07-27 E T A S R L PROCEDURE FOR THE DISTRIBUTION OF AN AGGLOMERATING AGENT ON EACH OTHER INCOHERENT PARTICLES.
DE10153593B4 (en) 2001-11-02 2005-11-17 Fritz Egger Gmbh & Co Apparatus and method for wetting wood fibers with a binder fluid

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3143895C2 (en) * 1981-11-05 1985-01-17 Triangel Spanplatten KG, 3177 Sassenburg Method and device for applying glue to particulate material in the form of chips, fibers or the like.

Also Published As

Publication number Publication date
EP0530501A1 (en) 1993-03-10
ES2079111T3 (en) 1996-01-01
ATE129660T1 (en) 1995-11-15
SE502518C2 (en) 1995-11-06
SE9102549D0 (en) 1991-09-05
DE69205772T2 (en) 1996-04-04
DE69205772D1 (en) 1995-12-07
SE9102549L (en) 1993-03-06

Similar Documents

Publication Publication Date Title
US5064689A (en) Method of treating discontinuous fibers
JPH04504287A (en) Discontinuous fiber processing method
US7207793B2 (en) Method and apparatus for introducing an additive to a composite panel
CZ2004555A3 (en) Device for wetting wood fibers with a binder fluid, method for wetting wood fibers with a binder fluid, process for producing fiberboard and the fiberboard per se
US4937100A (en) Process for the production of pulped cellulose material, in particular wood fibers, for the production of fiberboard and products produced
IE62452B1 (en) Apparatus and method of manufacturing synthetic boards including fire-retardant boards
EP0914914A2 (en) A process for distribution of a binder on loose particles
EP0821749A1 (en) Method for co-refining dry urban wood chips and blends of dry urban wood chips and thermoplastic resins for the production of high quality fiberboard products
RU2286248C2 (en) Mechanical spliced plate of wood material
US5792264A (en) Gluing machine for wood fibreboard panel production plants, and a plant using the gluing machine
US2761420A (en) Apparatus for applying sprayable materials to solid particles
CA1315064C (en) Method and apparatus for manufacturing fibre board sheets
EP0530501B1 (en) Method and device for glue coating of particles
JPH06509032A (en) Method for producing fiberboard from wood chips using isocyanates as binders
JPH04504233A (en) Natural fiber products coated with thermosetting binder materials
US4311555A (en) Method of manufacturing fiberboard
JP2002522251A (en) Manufacturing method of medium density board
CA2094940C (en) Atomized resin binding method and system for making wood-shaving panels
SE442724B (en) SET FOR MANUFACTURING FIBER DISKS ACCORDING TO THE DRY METHOD
US7182831B2 (en) Method and device for moistening fibrous raw materials with binding agents
JPH06285890A (en) Manufacture of molded from by waste paper fibrillated pulp
JPH03270901A (en) Method and apparatus for manufacturing flame retardant composite board
SE467244B (en) CLIMBING METHOD FOR MANUFACTURING FIBER BODIES ACCORDING TO THE DRY METHOD
JPS61108760A (en) Production of resin felt
SE189585C1 (en)

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT DE ES FR IT SE

17P Request for examination filed

Effective date: 19930322

17Q First examination report despatched

Effective date: 19940524

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): AT DE ES FR IT SE

REF Corresponds to:

Ref document number: 129660

Country of ref document: AT

Date of ref document: 19951115

Kind code of ref document: T

ITF It: translation for a ep patent filed
REF Corresponds to:

Ref document number: 69205772

Country of ref document: DE

Date of ref document: 19951207

ET Fr: translation filed
REG Reference to a national code

Ref country code: ES

Ref legal event code: FG2A

Ref document number: 2079111

Country of ref document: ES

Kind code of ref document: T3

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19960202

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19970630

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19970704

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: AT

Payment date: 19970715

Year of fee payment: 6

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: ES

Payment date: 19970729

Year of fee payment: 6

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: AT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19980730

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF THE APPLICANT RENOUNCES

Effective date: 19980731

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19990331

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 19990501

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

REG Reference to a national code

Ref country code: ES

Ref legal event code: FD2A

Effective date: 20001102

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20050730