SU1518123A1 - Method of producing wood flour - Google Patents

Abstract

The invention relates to the production of wood flour and can be used in the production of wood plastics. The purpose of the invention is to increase the moisture resistance, bulk density and reduce the ash content of flour. Steaming before pre-grinding facilitates grinding, and the introduction of a solution of sulfuric acid converts the amorphous part of the wood and the ash elements into a water-soluble state. The method allows to reduce the unit cost of electricity for grinding wood. Sulfuric acid consumption 0.3-0.6 wt.h. per 100 wt.h. Absolutely dry wood provides a decrease in water absorption by 2-6 times, ash content by 2.8-5.5 times and an increase in bulk density by 20-45%. 1 tab.

Description

one

(21) "3753 2 / 23-15

(22) 09.02.88

() 30.10.89. Bul V kQ

(71) Kirov Polytechnic Institute

(72) Z.I. Grebenkina, N.A.Hukov, A.S.Russkikh and G.V.Koltunova (53) 67.816 (088.8)

(56) USSR Author's Certificate K 686897, cl. In 27 K 5/06, 1978.

(Yvin N.M., Kottsov S.G., Shmakov I.V. Production of wood flour. N .: Lesna pryumyshlennost, 1982, p. 16.

(5) METHOD FOR PREPARING WOOD FLOUR

(57) The invention relates to the production of wood flour and can be used in the production of wood plastics. The purpose of the invention is to increase the moisture resistance, bulk density and reduce the ash content of flour. Steaming before the preliminary grinding facilitates grinding, and the introduction of a solution of sulfuric acid converts the amorphous part of the wood and the ash elements into a water-soluble state. The method allows to reduce the unit cost of electricity for grinding wood. Sulfuric acid consumption 0.3-0.6 mph. on 100 ma.ch. Absolutely dry wood provides a decrease in water absorption (value by 2-6 times, ash content by 2.8 - 5.5 times and an increase in bulk density by 20-45. 1 tab.

S

WITH

The invention relates to the production of wood flour and can be used in the production of wood plastics.

The purpose of the invention is to increase the moisture resistance, bulk density and reduce the ash content of flour.

Propelling before the pre-grinding allows easy grinding and warming up of the mass, into which the sulfuric acid solution is then introduced to convert the amorphous part of the wood and ash elements into a water-soluble state. With the consumption of sulfuric acid 0, .3 wt. by 100. wood amorphous part is not completely removed, which affects the moisture resistance. The ash elements are neutralized, and the residue of the acid is no longer enough

decomposition of the amorphous part of wood polysaccharides. The introduction of acid more than 0.6 wt.h. It does not increase moisture resistance, bulk mass and does not significantly reduce ash content, but reduces the yield of the finished product, since amorphous areas of cellulose decay and become water-soluble.

In addition, the proposed method makes it possible to reduce the unit cost of electricity for grinding the wood, since after removing the amorphous part of the wood, the remaining crystalline part is more easily subjected to mechanical grinding. The use of wood flour in the production of phenoplasts as a filler makes it possible to use them at higher temperatures, since the flour consists of

SP

00

INO

oo

R BASIC from cellulose, the temperature of destruction and melting of which is higher (230 ° C), mem branded amorphous part

The method is carried out as follows.

Example. Large wood waste is pre-crushed to even out the size. The prepared raw material is fed into the steam chamber, kept for 2 minutes in a medium of saturated steam at a pressure of 1.2 MPa, and milled under the same conditions in a disk mill. 0.1 mash is introduced into the ground wet mass. sulfuric acid monohydrate at 100 mash. absolutely dry (a.s.) wood, i.e. 20 kg of solution per 1 ton of a.s. wood Stand for 3 minutes under the same conditions. At the same time, the amorphous part of wood destructs and passes into iodine-soluble state. The decomposition products are extracted with water. The filtered residue is dried to a moisture content of 3% in a two-stage dryer and fed to the mill for grinding to the required dispersion.

Example2. Same as in example 1, but sulfuric acid in the amount of 0.3 mash is introduced into the ground wet mass. monohydrate per 100. completely dry wood.

EXAMPLE 3 Same as example 1, but O m.ch. eroic acid monohydrate at 100 mash. completely dry wood.

Example. Same as in Example 1, but 0.6 mash was introduced into the ground wet mass. monohydrate cone

0

five

about 5

.

35

acids per 100 mash completely dry wood.

Example p5. Same as in Example 1, but 0.8 wt.h. was added to the ground wet mass. sulfuric acid monohydrate at 100 mash. absolutely euh woods.

Example 6: Prototyping of wood flour was carried out using a prototype.

The indicators characterizing the {received wood flour, are given in the table.,

As can be seen from the Table, the consumption of sulfuric acid is 0.3 - 0.6 mach.h. monohydrate per 100 mac. woods, provides the best results in water absorption, wet density and ash content.

Energy consumption determined when grinding in a laboratory mill. to the prototype prototype, 270 kwh / t eoetavil, and l80 kWh / t according to the proposed epooeba, i.e. 1.5 times energy reduction occurs on grinding.

Claims (1)

Formula isotopic Making flour of wood flour, including pre-grinding, feeding, grinding, grinding and sorting, magnetic separation, and talting with the fact that, in order to increase the moisture resistance, loose density and reduce the ash pit of the flour, before the preliminary grinding, the raw materials are steamed, and before it is treated with a solution of eeric acid 0, 6 wt.h. ferric acid monohydrate at 100 mash. It is completely dry and extracted with water.