AU4363393A - Manufacture of fibre board - Google Patents
Manufacture of fibre boardInfo
- Publication number
- AU4363393A AU4363393A AU43633/93A AU4363393A AU4363393A AU 4363393 A AU4363393 A AU 4363393A AU 43633/93 A AU43633/93 A AU 43633/93A AU 4363393 A AU4363393 A AU 4363393A AU 4363393 A AU4363393 A AU 4363393A
- Authority
- AU
- Australia
- Prior art keywords
- fiber
- disintegrated
- glue
- dried
- board
- 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.)
- Granted
Links
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
-
- 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
- B27N1/003—Pretreatment of moulding material for reducing formaldehyde gas emission
-
- 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
- B27N3/00—Manufacture of substantially flat articles, e.g. boards, from particles or fibres
- B27N3/04—Manufacture of substantially flat articles, e.g. boards, from particles or fibres from fibres
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Wood Science & Technology (AREA)
- Forests & Forestry (AREA)
- Dry Formation Of Fiberboard And The Like (AREA)
- Paper (AREA)
- Laminated Bodies (AREA)
- Artificial Filaments (AREA)
- Multicomponent Fibers (AREA)
- Iron Core Of Rotating Electric Machines (AREA)
- Diaphragms For Electromechanical Transducers (AREA)
- Harvester Elements (AREA)
- Moulding By Coating Moulds (AREA)
- Reinforced Plastic Materials (AREA)
Abstract
A method for the manufacture of fiberboard according to the dry method starting with lignocellulose-containing material which is disintegrated, glued, dried, formed to a web and pressed. Prior to the defibering, the material is treated with an impregnation solution containing fiber surface activating chemicals and preheated.
Description
Manufacture of board
This invention relates to the manufacture of board of lignocellulose-containing material, such as fiber board.
Board of this kind is manufactured by disintegrating the material to particles containing fiber bundles and fibers. Glue is added to the disintegrated material and the material is dried and a web is formed which finally is pressed at increased temperature for curing the glue so that a board is formed. Fiber board is made of material which is disintegrated by defibering, i.e. of more or less free fibers.
The binding agent normally used is urea formaldehyde glue, which is admixed to the disintegrated material. The amount of glue can be 6% or more. The glue is relatively expensive, and it is therefore desired to minimize the glue addition. A smaller amount of glue, however, deteriorates the strength of the completed board. In view thereof, the glue addition must be optimized.
At the drying of the glued material, a great or small amount of water soluble formaldehyde is given off from the glue. After the separation of the drying gas from the fiber material, for example in a cyclone, the liquid content is condensed out of the gas. In conventional cleaning processes the water soluble formaldehyde then causes problems. The formaldehyde following along with the material to the final pressing also can cause problems when it is successively given off from the completed board. When glue is added to the material after its drying, the problem with formaldehyde separation arises at the pressing as well as from the completed board.
Fiber board manufactured according to the dry method normally is called MDF (Medium Density Fiberboard) and is a board product made of wood fiber. The yield exceeds 95%. The starting material preferably is wood chips, which are defibered with relatively low energy input, 100-500 kWh/ton fibers, for freeing the fibers. The defibered fiber material is glued, dried, formed to a web and pressed in a hot press. Alternatively, the material can be dried prior to the gluing. The material normally is preheated prior to the defibering to above 150°C whereafter the defibering is carried out under pressure at this high temperature
in order to facilitate the freeing of the fibers. At such a high temperature, however, the material can be degradated and iscoloured due to occurring hydrolysis. A short heating time reduces this shortcoming, but miscolouring yet cannot be avoided, and at the same time the energy consumption increases.
The urea formaldehyde glue normally used can be mixed with the fiber material on the conveying line (blow line) from the defibering apparatus or in a separate mixing device. The amount of admixed glue can be 6% or more.
When the fiber material subsequently is dried in a tube drier by means of gas at high temperature, a great or small amount of water soluble formaldehyde is given off from the glue. As stated above, the formaldehyde following along with the fiber material to the final pressing also can cause problems when it is given off successively from the completed board. This applies especially to gluing after the drying of the material, which can be carried out at the manufacture of fiber board.
The aforesaid problems can be reduced by the present invention, which simultaneously offers further advantages. According to the invention, the fiber material is treated with an impregnation liquid containing fiber surface activating chemicals and preheated before it is finally disintegrated.
Examples of such chemicals are such which affect the lignin, such as Na2S03 and NaHS03. These chemicals can be added in an amount of 1-30 kg/ton material expressed as Na2S03. According to the invention, it is possible to increase the ISO-brightness of the completed product, to reduce the energy consumption at the defibering, to reduce the glue amount at maintained strength or to increase the strength at maintained glue amount. Furthermore, also the formaldehyde separation can be reduced substantially.
The invention is described in greater detail in the following with reference to some embodiments thereof.
Fiberboard is manufactured by impregnating the raw material in the form of chips of, for example, softwood with lignin affecting chemicals, such as Na2S03 and NaHS03, in an amount of 1-30, preferably 10-20 kg/ton fiber material expressed as Na2S03.
The impregnation, which has to be carried out rapidly, can last some minute. Thereafter the temperature is increased to 150-200°C, preferably 160-180°C, for 2-3 minutes. However, the preheating can of course be performed prior to or at the same time as the impregnation. The pH value is kept within 2-12. This implies, that an impregnation solution with Na2S03 and NaHS03 will contain sulphite in the form of HS03 " and/or S03 2". The pH value suitably can be controlled by NaOH. Due to this chemical treatment (sulphonation) , the subsequent defibering can be carried out to the desired defibering degree with an energy input lower than normal. The energy consumption is in the interval 50- 400 kWh/ton fiber material. The energy saving can amount to about 10% compared with conventional defibering.
Owing to the impregnation, also the brightness of the completed fiber board increases.
As regards the fiber disintegration in the defibered material, it was found that both the fine material content and the shives content were reduced, i.e. the proportion of pri a fiber has increased.
It was also found at the impregnation according to the invention that the strength properties of the completed board have improved substantially. The tensile strength as well as the elasticity modules and the fiber bond have increased by at least 10%. Alternatively, this effect can be utilized for reducing the amount of glue addition at maintained strength properties. A 10% increase in the fiber bond corresponds to a 1% decrease in glue addition. The sulphonation according to the invention also implies, that the separation of formaldehyde can be reduced, due to the fact, that the sulphite ions in the impregnation solution react with the formaldehyde so that it is bound in the fiber material instead of being given off from the completed board.
EXAMPLE
Raw material in the form of chips was exposed to different impregnation treatment. One batch was treated with 10 kg Na2S03 per ton chips, and one batch with 10 kg NaHS03 per ton chips. A reference batch was not impregnated.
The different batches were preheated to about 170°C and thereafter defibered. In the blow line after the defibering, urea formaldehyde glue of the type E2 was added in an amount of 10% dry glue calculated on dry fiber. The material was thereafter dried to a dry matter content of about 90%. The fibers were dry formed to a mat, which was prepressed with a pressure of about 1.5 MPa and hot pressed for 5-6 minutes at 170°C. The board thus manufactured was tested on strength, ISO-brightness and formaldehyde content (perforator value) . The relative energy consumption for the different batches was also measured. The results were as follows:
Property Reference Na2S03 NaHS03 batch batch batch
Bending strength
MPa 38 . 4 43.8 40.0
Internal bond strength
MPa 1 . 8 2.1 2.0
ISO-brightness
% 24 26 26
Formaldehyde content mg CH2O/ 100 g 27 20 18
Relative energy consumption 1.0 0.95 0.95
The results confirm the technical effects stated above.
The invention, of course, is not restricted to the embodiments described above, but can be varied within the scope of the invention idea.
Claims (5)
1. A method of manufacturing fiberboard according to the dry method starting with lignocellulose-containing material which is disintegrated, glued, dried, formed to a web and pressed, c h a r a c t e r i z e d in that the material, before it is finally disintegrated is treated with an impregnation solution containing fiber surface activating chemicals in an amount of 1-30 kg/ton fiber material, expressed as Na2S03, and preheated to 150-200°C whereby the pH value is kept within 2-12 and that the disintegration is performed with an energy input of 50-400 kWh/ton fiber material.
2. A method as defined in claim 1, c h a r a c t e r i z e d in that the fiber surface activating chemicals are of a type affecting the lignin.
3. A method as defined in claim 2, c h a r a c t e r i z e d in that the impregnation solution contains Na2S03 and/or NaHS03.
4. A method as defined in anyone of claims 1-3, c h a r a c t e r i z e d in that the disintegrated material first is glued and thereafter dried before it is formed to a web.
5. A method as defined in anyone of claims 1-3, c h a r a c t e r i z e d in that the disintegrated material first is dried and thereafter glued before it is formed to a web.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE9201800 | 1992-06-11 | ||
SE9201800A SE470330B (en) | 1992-06-11 | 1992-06-11 | Process for making fiberboard according to the dry method |
PCT/SE1993/000388 WO1993025358A1 (en) | 1992-06-11 | 1993-05-04 | Manufacture of board |
Publications (2)
Publication Number | Publication Date |
---|---|
AU4363393A true AU4363393A (en) | 1994-01-04 |
AU662432B2 AU662432B2 (en) | 1995-08-31 |
Family
ID=20386472
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
AU43633/93A Ceased AU662432B2 (en) | 1992-06-11 | 1993-05-04 | Manufacture of fibre board |
Country Status (29)
Country | Link |
---|---|
EP (1) | EP0647174B1 (en) |
JP (1) | JPH07507735A (en) |
KR (1) | KR950701267A (en) |
CN (1) | CN1029461C (en) |
AT (1) | ATE143625T1 (en) |
AU (1) | AU662432B2 (en) |
BR (1) | BR9306513A (en) |
CA (1) | CA2136537A1 (en) |
CZ (1) | CZ281548B6 (en) |
DE (1) | DE69305165T2 (en) |
DK (1) | DK0647174T3 (en) |
ES (1) | ES2095060T3 (en) |
FI (1) | FI97032C (en) |
HR (1) | HRP930967A2 (en) |
HU (1) | HU213466B (en) |
ID (1) | ID841B (en) |
IL (1) | IL105811A (en) |
MY (1) | MY131192A (en) |
NO (1) | NO944779L (en) |
NZ (1) | NZ253367A (en) |
PL (1) | PL170405B1 (en) |
RU (1) | RU2083359C1 (en) |
SE (1) | SE470330B (en) |
SI (1) | SI9300293A (en) |
SK (1) | SK153094A3 (en) |
TR (1) | TR28107A (en) |
TW (1) | TW223036B (en) |
WO (1) | WO1993025358A1 (en) |
ZA (1) | ZA934108B (en) |
Families Citing this family (18)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TR22594A (en) * | 1987-04-07 | 1987-12-15 | Nur Emaye San Ve Tic Tic A S | STOVE PIPE EXTENSION APPARATUS |
DE4327774A1 (en) * | 1993-08-18 | 1995-02-23 | Fraunhofer Ges Forschung | Process for the production of medium density fibreboard (MDF) |
PL184356B1 (en) | 1996-04-12 | 2002-10-31 | Marlit Ltd | Method of obtaining composite lignocellulose materials |
GB9625068D0 (en) * | 1996-12-02 | 1997-01-22 | Marlit Ltd | Method for production of lignocellulosic composite materials |
DE69629038T2 (en) | 1996-12-09 | 2004-04-22 | Plato International Technology B.V. | Process for the production of cellulose fiber aggregates |
CA2292661A1 (en) * | 1997-07-11 | 1999-01-21 | Panagiotis Nakos | Manufacture of composite boards |
WO2006039914A1 (en) * | 2004-10-15 | 2006-04-20 | Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V. | Method for reducing the release of volatile organic compounds (voc) from wood and wood chip products and wood materials derived therefrom in particular particle boards |
LT1907178T (en) * | 2005-07-27 | 2016-11-10 | Kronoplus Technical Ag | Method for production of wood material articles with low emissions of chemical compounds |
SE530084C2 (en) * | 2006-09-04 | 2008-02-26 | Metso Panelboard Ab | Manufacture of wood fiber board containing on-site generated formaldehyde |
DE102007054123B4 (en) | 2006-11-15 | 2012-03-15 | Edmone Roffael | Process for the production of fiberboard with reduced formaldehyde emission, high moisture resistance and hydrolysis resistance of the gluing |
DE102007038041A1 (en) † | 2007-08-10 | 2009-02-12 | Kronotec Ag | Method for preventing the emission of aldehydes and volatile organic compounds from wood-based materials |
DE102008023007A1 (en) | 2007-11-11 | 2010-06-02 | Roffael, Edmone, Prof. Dr.-Ing. | Method for producing moisture-resistant and hydrolysis-resistant medium density fiberboard from e.g. derived timber product, involves using chemicals for pulping, where chemicals partially or completely replace resin in gluing phase |
DE102007055415C5 (en) * | 2007-11-19 | 2018-11-29 | SWISS KRONO Tec AG | Method for reducing the emission of saturated and unsaturated aldehydes from wood-based materials |
DE102008050428A1 (en) | 2008-10-08 | 2010-06-10 | Roffael, Edmone, Prof. Dr.-Ing. | Medium-density fiberboard manufacturing method, involves performing disintegration of fiber plates in presence of accelerator provided for alkaline hardening phenol formaldehyde resin and as potassium carbonate and/or sodium carbonate |
CN101786286B (en) * | 2010-04-20 | 2012-04-25 | 东北林业大学 | Manufacturing method for modified enzymolysis lignin composite board |
CN104690804B (en) * | 2015-02-14 | 2017-07-18 | 广西丰林木业集团股份有限公司 | A kind of manufacture method of electro-magnetic screen function fiberboard |
EP3059056A1 (en) * | 2015-02-23 | 2016-08-24 | Basf Se | Method for producing wood fibres and wood fibre boards |
CN109986676A (en) * | 2019-04-06 | 2019-07-09 | 安徽凯彦达环保餐具有限公司 | A kind of production technology for the disposable lunch-box that can be degraded in a natural environment |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DD205382A1 (en) * | 1981-12-23 | 1983-12-28 | Heinz Pecina | METHOD FOR ACTIVATING WOODEN PARTICLES FOR WOOD PRODUCTION OF MATERIALS |
DD242193A1 (en) * | 1985-11-06 | 1987-01-21 | Univ Dresden Tech | METHOD FOR PRODUCING WOOD MATERIALS |
SE466060C (en) * | 1990-02-13 | 1995-07-11 | Moelnlycke Ab | Absorbent chemitermomechanical mass and preparation thereof |
SU1721149A1 (en) * | 1990-06-25 | 1992-03-23 | Центральный научно-исследовательский институт бумаги | Method of producing thermochemically-treated pulp |
SU1724763A1 (en) * | 1990-07-10 | 1992-04-07 | Центральный научно-исследовательский институт бумаги | Method of producing bleached wood pulp |
-
1992
- 1992-06-11 SE SE9201800A patent/SE470330B/en not_active IP Right Cessation
-
1993
- 1993-05-04 CZ CZ943088A patent/CZ281548B6/en unknown
- 1993-05-04 AU AU43633/93A patent/AU662432B2/en not_active Ceased
- 1993-05-04 ES ES93913692T patent/ES2095060T3/en not_active Expired - Lifetime
- 1993-05-04 DE DE69305165T patent/DE69305165T2/en not_active Revoked
- 1993-05-04 NZ NZ253367A patent/NZ253367A/en unknown
- 1993-05-04 SK SK1530-94A patent/SK153094A3/en unknown
- 1993-05-04 RU RU9394046252A patent/RU2083359C1/en active
- 1993-05-04 JP JP6501367A patent/JPH07507735A/en active Pending
- 1993-05-04 WO PCT/SE1993/000388 patent/WO1993025358A1/en not_active Application Discontinuation
- 1993-05-04 DK DK93913692.5T patent/DK0647174T3/en active
- 1993-05-04 BR BR9306513A patent/BR9306513A/en not_active Application Discontinuation
- 1993-05-04 PL PL93306760A patent/PL170405B1/en unknown
- 1993-05-04 CA CA002136537A patent/CA2136537A1/en not_active Abandoned
- 1993-05-04 AT AT93913692T patent/ATE143625T1/en not_active IP Right Cessation
- 1993-05-04 EP EP93913692A patent/EP0647174B1/en not_active Revoked
- 1993-05-04 HU HU9403101A patent/HU213466B/en not_active IP Right Cessation
- 1993-05-04 KR KR1019940703807A patent/KR950701267A/en not_active Application Discontinuation
- 1993-05-17 TW TW082103924A patent/TW223036B/zh active
- 1993-05-20 CN CN93106167A patent/CN1029461C/en not_active Expired - Fee Related
- 1993-05-21 MY MYPI93000970A patent/MY131192A/en unknown
- 1993-05-25 IL IL10581193A patent/IL105811A/en not_active IP Right Cessation
- 1993-06-02 SI SI9300293A patent/SI9300293A/en unknown
- 1993-06-08 ID IDP614393A patent/ID841B/en unknown
- 1993-06-10 ZA ZA934108A patent/ZA934108B/en unknown
- 1993-06-11 TR TR00460/93A patent/TR28107A/en unknown
- 1993-06-11 HR HR930967A patent/HRP930967A2/en not_active Application Discontinuation
-
1994
- 1994-12-09 NO NO944779A patent/NO944779L/en unknown
- 1994-12-09 FI FI945790A patent/FI97032C/en not_active IP Right Cessation
Also Published As
Similar Documents
Publication | Publication Date | Title |
---|---|---|
EP0647174B1 (en) | Manufacture of board | |
EP1011939B1 (en) | Manufacture of composite boards | |
AU5064298A (en) | Method for use of recycled lignocellulosic composite materials | |
US5100511A (en) | Method for the manufacture of products containing fibers of lignocellulosic material | |
EP0199481B1 (en) | A process for the manufacture of cellulose pulps | |
US3202569A (en) | Cold caustic fiberboard manufacture | |
SK143695A3 (en) | Board and manufacture thereof | |
GB1595719A (en) | Method of applying one or more layers of surface stock to the web of base pulp in fibreboard manufacture by the wet-lay system | |
RU2080429C1 (en) | Wet method for manufacturing cardboard | |
DE19958756A1 (en) | Production of light-colored medium-density fibreboard (MDF) from old fibreboard comprises treatment with sodium sulfite, conversion into pulp and feeding into the blow-line of an MDF plant |