Method of production of pulp

FIELD: textiles; paper.

SUBSTANCE: method refers to production of pulp from flax raw material and can be used in the paper-pulp industry for producing of pulp for chemical processing as well as for example of cotton wool, paper and cardboad. The method is realised by means of consequent simultaneous tillage and purification of flax-cuke or flax straw, washing and cutting of the material. Then it is soaked, processed in a thermochemical way, washed through and bleached. Then it is washed again, wrung and dried. Following thermomechanic processing of the pulp containing material it is possible to perform maturation in the alkaline solution.

EFFECT: efficiency increase of method of producing of pulp from flax raw material with high degree of chaff.

2 cl, 1 tbl, 12 ex

 

The invention relates to pulp industry, namely the production of cellulose from cellulose-containing vegetable material, and can be used for pulp production from flax raw materials intended for generatenode, wool production, paper industry and so on

A method of obtaining cellulose from cereals, namely, that of plant cellulose raw material is cut into pieces 3-4 cm Sliced evenly sprinkle 15-40%solution of NaOH or KOH in water ratio 2:5 and mix thoroughly. The weight of the load in a closed container and process compressed air (pO2<1 ATM). Washed with water and dried. Pulp output is 46,2% (Accepted Japan's bid No. 52-6362, CL 39 A4, 1977).

However, the known method it is impossible to obtain high-quality cellulose of the linen raw material with a high yield of the target product.

A method of obtaining cellulose by loosening plant materials, alkaline cooking using NaOH, surface-active substances (surfactants), T=120-130°C for 1 hour, rinsing 1-5-fold amount of clarified water hydrocyclone cleaning the clarified water, grinding, fine hydrocyclone cleaning the clarified water, 2-fold bleaching NaOCl at pH=9-11,5, T=90°C for 1 hour, rinsing 2 times umaczeniowej, kislovka solution of H2SO4when 15-40°C for 1 hour, rinsing, softened water, wringing, drying air (Constant technological regulation No. 4-2 "Production of esters and ethers of cellulose", approved on 18 January 1995, Gene. Director Engels JSC "Khimvolokno").

A method of obtaining cellulose, including mechanical treatment of cellulose-containing material by its simultaneous loosening and cleaning, boiling in an alkaline solution at a temperature of 130-140°under the pressure of 3-4 ATM for 180-210 min, rinsing, bleaching in acid solution with sodium hypochlorite, centrifuge, loosening and drying (EN 2078163, CL D04H 1/02, epubl).

The disadvantages of the above methods are: the process of alkaline cooking in harsh conditions and at temperature T=120-140°C, pressure P=2-4 ATM, bleaching carcinogenic sodium hypochlorite.

The closest analogue is the method of obtaining cellulose by simultaneous loosening and clearing a cellulose-containing material, grinding, steeping in a solution of NaOH and cleaning, alkaline cooking for 1.5-3 hours at a water ratio of 1:(5-20), additionally containing surfactants, washing, bleaching in a solution of N2About2, rinsing, wringing and drying (Patent of the Russian Federation on the Application number 2005127650 with the decision on the grant of a patent on 27.02.07).

The disadvantage of this method of having aetsa the impossibility of obtaining cellulose from flax raw materials with a high degree of zakostrennost, in particular from flax straw and flax silence.

The basis of the offer of the invention is the creation of efficient, cost-effective method of producing pulp from flax raw materials with a high degree of zakostrennost and flax Selenza suitable for generatenode, wool production, paper industry and so on

The problem is solved so that, in the method of producing pulp by successive simultaneous loosening and clearing a cellulose-containing material, locks, thermochemical processing, washing, bleaching, washing, pressing and drying, before zamocky additionally carry out the washing and cutting of the material, the treatment is carried out termomekhanicheskoe, and as a cellulose-containing material take flax-Zieleniec or flax straw.

In the embodiment of the method according to claim 1 additionally after termomekhanicheskoi material handling his leave ripening in alkaline solution.

As a cellulose-containing material used flax raw materials: linen-Zieleniec - stems collected in the period between flowering and early yellow ripeness of flax plants (40-50 days) before the beginning of intensive accumulation of lignin (Zhivetin CENTURIES, L. Ginzburg, Olshanskaya O.M. Flax and its comprehensive use. - M.: information-Knowledge, 2002, at 400 C.) and/or straw oilseed crops (crown flax, flax-between who has umoc) after separation of the seed.

The process according to the invention carried out using the following apparatus and chemicals as follows.

Loosening and cleaning flax raw material is carried out simultaneously with keeporiginal types SRC, GRP removal of mechanical impurities, weeds, flowers, seeds.

The loosened materials by pneumatic transport goes in the washing machine, where the process water containing 0.5% of surface-active substances (surfactants) remove dust and dirt.

As the surfactant used sintana-ALM-10 - monoalkyl ether of polyethylene glycol on the basis of the highest synthetic fatty alcohols on THE 6-14-864-88 or Neonol AF9-12- monoalkylphenol based trimers of propylene in THE 2483-077-05766801-98.

Then flax raw materials are cut using a multi-disc mill type MDR-379 to the length of the chaff 10-15 mm

Locked to spend in the auger apparatus with reverse zones type AL-200 in alkaline solution, prepared by circulating water with NaOH content - 10-60 g/l and surfactant - 0.5 g/l, for 15-60 minutes at a temperature of 95-100°C. Hydraulic module equal to 1:(10-20).

The prepared slurry with a concentration of linseed raw 5-10% is subjected termomekhanicheskoi processing in screw machine Cam zones type AL-200 at a temperature of 95-100°C for 15-30 minutes.

The spent alkaline solution with dissolved in it n the components of flax pulp raw material is separated from the flax pulp pumping for possible re-use.

Semicellulose mass is subjected washed in softened water to remove residual alkali from semichemical pulp. Surgery is performed in 2 stages by storage in tanks with water at a temperature of 80-90°C for 20-30 minutes in the first stage and 40-50°C for 20-30 minutes on the second level. Hydraulic module when washing is 1:(10÷20) at each step.

The bleaching of flax pulp is carried out in the hydrogen peroxide solution with a concentration of 5-10 g/l at a temperature of 85-95°C for 90 minutes. The hydraulic module 1:(10÷20).

Leaching from the bleaching solution carried out softened water, as in washing after surgery alkaline cooking.

The pressing operation is carried out on type centrifuge AG or AG to a moisture content of 40-50%.

Drying cellulose conduct flue gases at a temperature of 140-160°With vibrosource.

The dried pulp is fed into the cyclone for separation from the air and then on the package.

According to claim 1 FIS. after termomekhanicheskoi processing if you need to improve the physico-chemical characteristics of cellulose spend maturing in the same alkaline solution doripenem to the concentration of NaOH 10-60 g/l at a temperature of 95-100°C for 30-60 minutes and serves on washing softened water in 2 stages, as described above.

To prove the conformity of the way CR is the criteria of "industrial applicability" presented concrete examples of implementation of the method.

Example 1.

100 kg unpacked flax silence served in cyprusregistered with a capacity of 22 kW and a capacity of 800 kg/h, where they were rastraivaius and removal of random mechanical inclusions, weeds, roots, etc. are Loosened and the raw material is washed in a cylindrical tank 3 m3technical water containing 5 g/l cintanya ALM-10.

Purified linseed raw cut on multi mill MDR-379 (power of 10 kW, capacity 25 tons/day) to the fiber length 10-15 mm

Then chopped flax-Zieleniec and 2 m3alkaline solution with a concentration of NaOH 10 g/l recycled water and 0.5 g/l cintanya ALM-10 serves to screw the device AL-200 reverse zones (capacity 1000 kg/h), preheated to a temperature of 100°and hold locked in for 60 minutes. Then cooked pulp massanassa (performance - 470 m3/h) is transported in a screw machine AL-200 containing the Cams, and spend termomekhanicheskoe processing for 30 minutes at a temperature of 100°C.

At the end termomekhanicheskoi processing and separation of the spent solution flax pulp twice washed in a volume of 10 m3softened water for 30 minutes at a temperature of 85±5°and for 30 minutes at a temperature of 35±5°Chydrauliczny module is 1:20.

Then p is washed linen pulp is placed in a container with a volume of 10 m 3with a solution of hydrogen peroxide concentration of 10 g/l for bleaching at a temperature of 90°C for 1.5 hours. Hydraulic module when the bleaching is 1:20.

Bleached pulp is washed with softened water in a volume of 10 m3first for 30 minutes at a temperature of 85±5°C, then for 30 minutes at a temperature of 35±5°C. Hydraulic module at both stages of this flushing is 1:20.

Suspension of flax pulp massanassa served on a horizontal centrifuge (capacity 900 kg/h). The pulp is squeezed to a moisture content of 40%.

Drying of the cellulose is carried out by feeding flax pulp in vibracoustic. Flue gas temperature is 140-160°Poluchat the pulp with a yield of 60%, with mass fractions α-pulp - 94%, dynamic viscosity 16 mPas·C.

Example 2-3 behave analogously to example 1, by changing the process conditions. Data examples are presented in table 1.

Example 4.

The same conditions as in example 1, but to increase the mass fraction αpulp to enter the operation ripening after termomekhanicheskoi processing. The pulp goes to the screw apparatus of the AL-200 reverse zones (capacity 1000 kg/h), where a worker alkaline solution doubleplays to the alkali concentration of 10 g/L. Ripening is conducted for 60 minutes while the temperature is th 100° Spoke washing softened water in two stages and bleaching (concentration of H2About25 g/l, temperature is 95° (C) the rest is performed according to the conditions of example 1. Get the pulp with a yield of 57% and an ash content of 0.2%.

Example 5-6. Cellulose receive analogously to example 4, by changing the process conditions (see table 1).

Example 7-12. The method is carried out analogously to examples 1-6, only as a source of raw materials use straw flax (table 1).

Physico-chemical characteristics of the target product are determined according to GOST 595-79 "Cellulose cotton" (see table 2).

Analysis of the data of tables 1 and 2 shows that the proposed method is effective because it allows you to obtain cellulose used for generatenode, wool, paper, cardboard, etc. And use as feedstock straw oilseed crops (waste of flax oil or flax silence (stems collected in the period between flowering and early yellow ripeness of flax plants (40-50 days), significantly reduces the cost of pulp.

Table 1
Technological parameters of the methodUnitsThe examples and the value of the parameters
12 456789101112
Raw materialsFlax-ZieleniecStraw flax
Timocka using

- caustic soda
g/l146146235235
- cintanya ALM-10g/l0,50,5-0,50,5-0,50,5-0,5-0,5
- neonols AF9-12g/l--0,5--0,5--0,5-0,5-
Temperature°100100100100100100100100100100100100
Durationmin60 6030603015606060303015
Hydraulic module1:201:201:201:201:201:101:201:201:201:201:201:10
2. Termomekhanicheskoe processing
Temperature°100100100100100100100100100100100100
Durationmin303030303030151515151515
3. Ripening

Temperature


°
--- 100100100---100100100
Durationmin---603030---451515

Continuation of table 1
4. The bleaching solution of hydrogen peroxideg/l101010555101010555
Temperature°909090959595909090959595
Durationmin909090909090909090909090
Hydraulic module1:201:201:201:20 1:201:101:201:201:201:201:201:10

0,3
Table 2
Name of indicator quality of flax pulpUnitsExamples and parameter values
123456789101112
1. Mass fraction αpulp%94,094,79595,89695,69190for 91.392,89392,5
2. Dynamic viscosityMPa·2643756010186183457214326
3. Mass fraction of ash%0,30,281,170,20,210,200,410,390,330,210,26
4. White%707580737572607063656160

1. The method of producing pulp by successive simultaneous loosening and clearing a cellulose-containing material, locks, thermochemical processing, washing, bleaching, washing, pressing and drying, characterized in that before zamocky perform additional washing and cutting of the material, the treatment is carried out termomekhanicheskoe, and as a cellulose-containing material take flax-Zieleniec or flax straw.

2. The method according to claim 1, characterized in that it further after termomekhanicheskoi material handling his leave ripening in alkaline solution.



 

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1 tbl, 4 ex

The invention relates to the production of cellulose and can be used in the pulp and paper industry

The invention relates to the pulp and paper industry, in particular to a technology for pulp for paper and chemical processing
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