SU861443A1 - Cooking liquor for producing sulphate cellulose - Google Patents

Description

The invention relates to the field of cellulose paper production, namely to cooking solutions for the preparation of sulphate pulp. The task of the cooking process is to completely remove the pulp from wood for a specific purpose or in an incompatible form by dissolving lignin, as well as other related substances. The dissolution of the Nina leagues occurs under the action of the cooking liquor, to soften the effect of the pulpite on cellulose and to increase the yield of cellulose, the solution contains additives that include organic substances. A cooking solution is known for obtaining sulphate cellulose of increased yield containing sodium sulphide and hydroxide and the additive / answer to the formula: R () „(O), in an amount from 0.05 to 1.0% by weight of absolutely dry 1D wood. At the same time, R is a nucleus of a compound containing active hydrogen and taken from the group of substances including ethylene glycol, 1-3 - butylene glycol, 2-3 butylene glycol, propylene glycol, 1-5 - pentanediol, etc. In this case, m - is changed in such a way that the oxipropylene chain has a molecular weight of from 900 to 25,000 units, and n - changes in such a way that the weight of the oxyethylene groups is from 10 to 90% by weight of the weight of the mixture. The concentration of active alkali in the solution is 15-22 wt.%, By weight of absolutely dry wood chips. The ratio of liquid to wood mass is 3: 1 and 5: 1. The disadvantage of this cooking solution is that it contains an expensive scarce synthetic organic compound. A cooking liquor is known to produce sulphate pulp, which contains one stripped off liquor containing 146 g / l or 187 g / l N320 and spent liquor from neutral sulphite cooking of semi-cel c) on a sodium base, taken in an amount of 5-12% by weight absolutely dry wood in terms of the dry residue of lye. Hydromdul cooking is 3-4: 1 2. However, this cooking solution does not allow to obtain a total pulp yield of more than 51.1%. The aim of the present invention is to increase the yield of pulp during sulfate pulping. The goal is achieved by the fact that the cooking liquor for the production of sulphate pulp containing white sulphate lye and a lignin-containing product of chemical processing of wood contains, as a lignin-containing product, an alkaline extract of hydrolytic lignin at a ratio of white liquor and alkaline extract of 1: 3-: 3.7, The total organic matter content in the solution is 3-9% by weight of absolutely dry wood. The extract of hydrolytic lignin, obtained after treatment with alkaline reagent (beagle lye or sodium hydroxide) at an atmospheric temperature of 60 minutes, contains 92 g / l - 47 g / l dry matter, including 13-31 g / l Organic substances. Organic substances consist of 10–20% of resinous substances, 15–25% of carbohydrate degradation products and 55–75% of solid and colloidal lignin. The complex of these organic substances (products of destruction of carbohydrates, first of all 1 cellulose and lignin) has a protective effect on cellulose, which leads to an increase in its output during sulphate cooking. The amount of organic matter of the hydrolytic lignin alkaline extract in the cooking solution less than 3% by weight of absolutely dry wood does not affect the yield of pulp during sulphate cooking. With an increase in the amount of organic substances in the hydrolytic lignin extract of more than 9% by weight of absolutely dry wood in a cooking solution, no significant increase in the yield of cellulose is observed. The components of the cooking solution are taken in the following ratio:. white liquor: alkaline hydrolytic lignin extract 1: 3.0-3.7. Pine chips of laboratory preparation are cooked according to the following graph: heating to a temperature of 160 clays, aging at 172 ° C -90 min. The consumption of active alkali in units is 16% of the mass of wood. The hydronic module cooking - 1: 5. i. Example A solution of an alkaline hydrolytic lignin extract was obtained according to the following technology, 200 g of hydrolytic lignin of a powdery type obtained at the Segezhsky hydrolysis plant and produced with a moisture content of 63.1% were treated with white liquor in the amount of 316 ml, concentration of 124.6 g of N320 and sulphidity of 28% , 8% at a temperature of 90 ° С, a water ratio of 1: 6 for 60 minutes. Then, the obtained alkaline extract i of hydrolytic lignin, ideally, was separated by centrifugation from the solid residue within minutes. The obtained solid residue was rumsed with hot water in an amount of 0 ml. the washings were combined with the hydrolytic lygin fir extract. In total, 20% of the initial hydrolytic lygin originated in the solution. The solution contained 91.56, g / l of dry matter, including: 13.85 g / l of organic matter. The concentration of active alkali in the obtained rateor was 20.6 g / l. Laboratory pine pod chips with a moisture content of 8.0% in a quantity of 70 g of absolutely dry wood chips were loaded into an autoclave with a capacity of 0.4 l. A cooking solution was added that contained: 60 ml of white liquor with an active alkali concentration of 125.6 g / l and a sulfide content of 28.8%, 180 ml of an alkaline extract solution with a concentration of organic substances. 13.85 g / l, which is in the cooking solution of 3.8% organic matter by weight of absolutely dry chips. The consumption of active alkali white liquor was 16% Na.2.0 of the weight of absolutely dry chips. The cooking was carried out according to the following schedule: heating to the temperature was 172 s160 min, the duration of boiling at –90 min. Hydronic module cooking 1: 5. Cooking was carried out in triplicate. In tab. 1 presents the average data on the characteristic of the obtained cellulose. PRI me R 2 p A solution of an alkaline hydrolytic lignin extract was obtained: 200 g of hydrolytic lignin in the form of a powder obtained at the Segezhsky hydrolysis plant, humidity 63.7%, treated with white liquor in the amount of 310 ml, concentration 125.2 g / l HagO and sulfide 28.8% at a temperature of 90 ° C, water ratio 1: 6 for 60 clay. Then, the obtained alkaline hydrolysis lignin extract in the form of a solution was separated by centrifugation from the solid residue for 5 clays. The obtained solid residue was washed with hot water in an amount of 50 ml. The washings were combined with an alkaline hydrolytic lignin extract. In total, 20.5% of the substances of initial hydrolytic lignin passed into the solution. The solution contained 72.78 g / l of dry matter, including 14.53 g / l of organic matter. The active alkali concentration in the resulting solution was 17.36 g / L. Laboratory preparation pine chips of 8% in the amount of 60 g of absolutely dry chips were loaded into a 0.4 l autoclave. A cooking solution was added, which contained: 65 ml of white liquor with active alkali concentration, 86.4 g / l NajO and 29.9% sulfidity, 240 ml of alkaline extract solution with organic matter concentration 14.53 g / l, which amounted to a solution of 5.7% organic matter by weight of absolutely dry chips. The consumption of active alkali of white liquor was 16% of the weight of absolutely dry chips. The cooking was carried out according to the following schedule: heating to a temperature of -160 minutes, the duration of cooking at 90 minutes. Hydronic module cooking 1: 5.

Cooking was carried out in triplicate. The table presents the average data on the characteristics of the obtained cellulose.

PRI me R 3. A solution of an alkaline hydrolytic lignin extract was obtained: 100 g of hydrolytic lignin in the form of a powder obtained at the Segezhsky hydrolysis plant with humidity of 64.7% t was treated with a 150 gallium-NaOH solution of NaOH in a concentration of 125 g / l Na. jO at a temperature in the water ratio 1: 6 for 60 min. The obtained alkaline extract was separated from the solid residue by centrifugation for 5 minutes. The solid residue was washed with 50 ml of hot water. The whole extract was treated with a new batch of hydrolytic lignin (100 g) under the above conditions to increase the organic matter content of the solution. Then, the obtained alkaline hydrolytic lignin extract was separated from the solid residue by centrifugation for 5 minutes. The remaining solid residue was washed with a solution of wash water used during the washing of the first portion of hydrolyzed lignin. The alkaline extract solution was combined with prod. The resulting solution contained 47.2 g / l dry matter, including: 31.1 g / l organic matter. The concentration of active alkali in the solution was 12.4 g NagO.

Laboratory preparation pine chips with a moisture content of 8% in the amount of 65 g of absolutely dry chips were loaded into a 0.4 liter autoclave. A cooking liquor containing 54 ml was added.

0 white liquor with a concentration of 138.3 g / l and a sulfide awn of 28.8%, 190 ml of the previously obtained solution of an alkaline extract of hydrolytic lignin containing 31.1 g / l of organic substances, which accounted for the concentration of organic substances in the cooking melter 9% of the weight of absolutely dry wood chips. The consumption of active alkali white liquor 1b% N320 by weight of absolutely dry chips. The cooking was carried out according to the following graph: heating to –120 min; holding at –90 min. The hydronic module cooking 1: 6.

The cooking was carried out in triplicate, the table shows the average data of the pulp produced.

At the same time, for comparison, the laboratory preparation of pine chips was carried out under these conditions with white liquor at a consumption of active alkali of 16% of the weight of absolutely dry chips, and with a mixture of white and black liquor with a consumption of active alkali of 16%, also in triplicate. Black liquor from the sulphate melt of the main chip was taken in such quantity that the content of organic substances in the cooking solution was 6% of the weight of the flail. For now: ateli obtained cellulose pres1; avleny in the table.

Yield.cellulose from absolutely dry wood,%

TCHSHLOVO SHLHOD

oils,%

Breaking length, (. M. Resistance to fracture, the number of double kinks.

Claims (2)

Resistance to pressing, kgf / cm;:; tear resistance, HS As can be seen from the table, the yield of cellulose during cooking with the proposed cooking solution is significantly higher compared with data on the yield of cellulose during cooking with white liquor and with a mixture of white and black liquors. The optimal content of organic substances of alkaline hydrolytic lignin extract in the cooking solution is within 3–9% of the weight of absolutely dry wood, and with a further increase in their amount, the yield of cellulose remains almost unchanged. The table shows the mechanical parameters of the obtained cellulose with a milling of 60 ° SR and a casting weight of 75 g / m. According to the table, it is clear that sulphate unbleached cellulose obtained with an increased yield meets the requirements presented by lm to HC-2 celosis (example 1) and mark NS-3 (example 3) according to GOST 11208-65. High-strength packaging or wrapping papers can be obtained from the obtained pulp. With the introduction into the cooking solution of an alkaline extract of hydrolytic lignin containing up to 20% resinous and fatty substances, the yield of sulphate soap from sulphate cooking of pine chips increases, on average, by 25%. Claims Cooking solution for producing sulphate pulp, containing white sulphate liquor and lignin-containing product of chemical processing of wood, characterized in that, in order to increase the yield of cellulose, it contains as the lignin-containing product an alkaline extract of hydrolysis lignin with a ratio of white liquor and alkaline extract 1: 3-3,7, while the total content of organic matter in the solution is 3-9% by weight of absolutely dry wood. Sources of information taken into account in the examination 1. US patent 3,909,345, cl. D 21 C 3/20, 162-72, 162-82, 1974. 2. Authors certificate of the USSR I 539113, cl. O 21 S 11/00, O 21 S 3/02, 1976 - prototype