LT6163B - Plant fiber panels and their method of manufacture - Google Patents

Abstract

The present invention relates to the fibrous plant panels, specifically to the panels of hemp fibre that can be used in the manufacture of environmentally friendly furniture. Invention aims to produce a completely ecologically clean fibrous panel, without chemical additives, but with a good mechanical properties. The task is realized in that the mass, consisting of main components: hemp fibers and soft bast particles - 90-95 %, paraffin emulsion - 0,2-0,5 % and 5-6 % water, is chopped, swelled, diluted and from the mass are shaped panels. Chopped hemp fibers and soft bast particles are fed into the swelling chamber where the mass is swollen for 3-5 minutes at 180-200 oC and 10-12 atm, once again is crushed, diluted with circulation water 1.4 to 2 % concentration, is mixed with the paraffin emulsion, from the formed layer is collected water and the mass is hot-pressed at 90-220 oC.

Description

FIELD OF THE INVENTION The present invention relates to fibreboard panels, particularly hemp fiber panels, which can be used in the production of eco-friendly furniture. There is a known wet board manufacturing process which consists in preparing the pulp from fibrous raw materials such as chips and sawdust and adding the binder before the board is dried and pressed, ie the binder (low soluble resin or concentrated resin) is added before the pulp. preparation (LT 3163 B, 021 H 17/06). These fiber boards use harmful chemicals in their production, and the use of wood is quite expensive.

There is also a known method of producing eco-friendly hardboard, which is used to crush, mix, mix pulpwood and flax pulp and dyeing-healing extracts, to form the resulting pulp on the mesh, to compress and to dry at high altitude. at temperature (LT 3892B, B27N 3/04).

Although this method of making hardboard is ecologically clean, the use of wood is quite expensive as it takes quite a long time for the trees to regenerate.

The closest embodiment of the present invention is a fiber product made from flax or corresponding stem fiber plants, made of both true straw fibers and woody pulp and filaments derived from the same plant material, blended with synthetic binder fibers which, when exposed to heat, soften to the glue. and consolidates the forming structure at cooling. Yes, in conjunction with pressing, thermal bonding is performed (LT 99-003 A, A01G 9/10, D04H 1/54, E04B 1/74, E04C 2/10).

It uses noxious synthetic materials to produce this fibrous product, the resulting fibreboard is ecologically impure, and the resulting fibreboard is not durable and is used for softer, matting-like products.

The object of the present invention is to make a fiber board completely ecologically clean without the use of chemical additives but having good mechanical properties.

The aim is achieved by grinding, grinding, diluting with water and from the main components: 90-95% hemp fiber and soft husk particles, 0.2-0.5% paraffin emulsion and 5-6% water. mixed masses form panels. The crushed hemp fiber and husk particles are first fed into a J-firing chamber where the mass is fired for 3-5 minutes. at 180-200 ° C and 10-12 atm, the resulting mass is again crushed and mixed, diluted to a concentration of 1.4-2% with circulating water, mixed with paraffin emulsion, suctioned from the formed layer and hot pressed at 90-220 ° C.

Cannabis is an annual herbaceous plant. Its stems can be 0.5 - 5 m high. fiber. The length of the elementary fibers is 10-14 mm and that of the technical fibers 50-250 mm. Cannabis is widely used in a variety of products, and due to its anatomical structure it is also well suited for the production of violin plates. The fiber of these plants is made up of a large proportion of cellulose fibers which, as a rigid structural material, form the basis of sheets formed by wet or dry (fiber-felting) processes.

Hemp fiber board is an eco-friendly material made from a blend of hemp fibers and woody husk particles by hot pressing. Fiberboard thickness of 1.5 mm or more. Particle binding occurs during fiber mat formation due to fiber binding properties.

The production method of the present invention is suitable for conventional slab production equipment (used in industry for the production of hardboard). Violets of hemp stems are heated with saturated steam and then fed to defibrator mill chambers to prepare the pulp. When recycled water is added, the mass concentration of the substances is about 2.5%. This mass is fed to the refiner for final fiber preparation. From the refiner, the pulp is fed to a forming clinic with mixer, which is further diluted to a concentration of 1.4-2%. The mass is then pumped into a forming-clinic box, where it is mixed with paraffin emulsion. The mass is then drained, compressed and dried in a hot press.

Because the hemp fiber board is made up of hemp fibers and husk particles, paraffin emulsion, and water taken in an appropriate ratio, and due to its favorable fiber binding properties, synthetic binders are not required. Paraffin emulsion is required to impregnate the fiber particles to reduce their swelling.

Here is an example of how to obtain a hemp fiber board (we add a known scheme of fiber board production equipment).

EXAMPLE

Preparation of the pulp:

The cannabis fiber violins are fed from the hopper above the defibrator into the upper defibrator auger feeder (1) with adjustable rpm and through it into the firing chamber (2).

Saturated steam (180-200 ° C, 10-12 atm) is fed to the curing chamber. Curing takes 3-5 minutes. From the firing chamber, the violins are fed into the defibrator (3) mill chambers by means of a screw. The pulverized mass is discharged into cyclones (4) above the intermediate basin (5).

In cyclones, the mass is circulated with circulating water into a defibrator mass intermediate basin fitted with a paddle stirrer.

From the pool, the mass is automatically fed to the refiners (6) where it is milled. The aggregate mass, with a concentration of 3-3.5% and a temperature of 60-70 ° C, enters the refinery mass basins (7, 8), which are diluted with circulating water to a concentration of 2.5%.

From the refinery mass pool, the masses are pumped into the bedding clinic (9) with a stirrer at a concentration of 1.4 to 2%. The forming box automatically enters the pressure box (10) of the line molding machine. Part of the pulp from the box enters the intermediate layer of the upper layer and from there into the high mill refiner. After the third milling step, the finely ground pulp enters the upper layer pool (7), from where it is pumped to the upper layer forming box (11) and from there to the upper layer pressure boxes (12).

Casting process:

From the line refiner, the pump mass is pumped into the line refiner, then pumped to the bed basin forming box with agitator, which is diluted with circulating water. The mass passes through the concentration regulator. From the molding to the casting box, the mass is self-propelled into the press box of the injection molding machine.

In the pipeline, the mass is diluted with circulating water before entering the injection box press box. The molding process begins when the mass from the press box is fed to the molding machine net. The feed rate at the outlet to the grid must be close to the grid's movement speed. The mass transfer from the core layer mass formation adhesive box is returned (13) to the refiner mass pool.

The top layer mass is fed from the line basin by means of a pump into the top layer forming-laying box (11) into which the paraffin emulsion (14) is dosed.

From the upper layer, the mass of the continuous forming adhesive box is self-propelled into the filling boxes, from which the mass is uniformly poured onto the formed main fiber carpet layer. The vacuum system draws water from the formed carpet, then three rows of press rolls (15) and three larger press rolls (16) finally form the carpet and squeeze the water.

Pressing process:

The fiber carpets, which are covered with conveyor nets, are loaded into the loading ejector (17), from which they are pushed into the baler, where it is pressed. Pressing takes place in three phases: I - 25-27 MPa, pressing time 1.5 minutes; II - 4-6 MPa, pressing time 3-5 minutes; III - 25-27 MPa, pressing time 1-2 minutes. Pressing temperature 190 - 220 ° C.

After pressing, the plates are pulled into the discharge ejector.

Such hemp fiber boards can be used to make interior surfaces of furniture, decoration of living and public areas and other consumer and multi-purpose products that are not stored in humid areas.

Here are the physical-mechanical characteristics of the hemp fiber board (thickness 2.5 / 3.2 mm, density 800 kg / m ³ ):

Feature Test method Miss Nominal thickness limits (mm) <3.5 > 3.5 to 5.5 &Gt; 5.5 Thickness swelling within 24 h EN 317 % <35 - - Internal clutch EN 319 N / mm ² > 0.5 - - Bending strength EN 310 N / mm ² > 30 - -

For comparison purposes, we present the Requirements for general purpose boards for use in dry environments according to the European version of European Standard EN 622-2: 2004:

Feature Test method Unit Nominal thickness limits (mm) s 3.5 > 3.5 to 5.5 &Gt; 5.5 Thickness swelling within 24 h EN 317 % 37 30th 25th Internal clutch EN319 N / mm ² 0.50 0.50 0.50 Bending strength EN 310 N / mm ² 30th 30th 25th

A comparison of the indicators shows that hemp fiber boards meet the requirements.

Claims (2)

DEFINITION OF INVENTION 1. Fibreboard and a process for the production thereof comprising the step of milling, blending and forming a fiberboard in the form of a ready-to-use fiberboard, characterized in that the weight of the main components: 90-95% hemp fiber and husk particles, paraffin emulsion - 0.2 - 0.5% and 5 - 6% of water, grinds, brushes, dilutes with water and forms panels from the mixed mass. 2. A method according to claim 1, characterized in that the crushed hemp fiber and the husk particles are first fed to a digestion chamber where the mass is agitated for 3-5 minutes. at 180-200 ° C and 10 -12 atm, the resulting mass is again crushed and mixed, diluted with a circulating water concentration of 1.4-2%, mixed with paraffin emulsion, suctioned from the formed layer and hot pressed at 190-220 ° C.