SU1666607A1 - Method for preparing cooking liquor for cellulose manufacture - Google Patents

Abstract

The invention relates to the technology of production of cartridge and sulphate pulp and reduces the content of resinous substances and lack of penetration in cellulose, while simultaneously increasing its yield and physical and mechanical properties. Sodium hydroxide or a mixture of its sodium sulfide is dissolved in the post-yeast brew of the hydrolysis production, after which polyacrylamide is added to the resulting solution in an amount of 0.05-0.20% by weight of absolutely dry wood chips required for cooking. 3 tab.

Description

The invention relates to the pulp and paper industry and can be used in the production of soda and sulphate pulp for the manufacture of various types of paper and cardboard.

The aim of the invention is to reduce the content of resinous substances and lack of penetration in cellulose, while simultaneously increasing its yield and physical and mechanical properties.

The proposed method is carried out by dissolving sodium hydroxide or combining it with sodium sulfide in a post-yeast brew (PDB) of the hydrolysis production and then introducing into the resulting solution of polyacrylamide in an amount of 0.05-0.20% by weight of absolutely dry wood chips.

The invention is illustrated by the following examples.

PRI me R 1. 6.3 g of sodium hydroxide are dissolved in PDB. The content of active alkali in the resulting solution is 18% of the mass of absolutely dry wood (a.s.d.) required for boiling. Then, polyacrylamide is added to the solution in an amount of 0.05-0.20% by weight of a.s. With cooked cooking solution in a volume of 140 ml, sodium boiling wire 35 g of pine wood chips. Cooking is carried out in parallel autoclaves according to the temperature schedule; temperature rise from 80 to 145 ° C - 70 minutes; 100 nka at a temperature of 145 ° C - 50 min; rise to 172 ° С - 45 min, stand at 172 ° С - 90 min.

As a control, soda wood is boiled from pine wood, for which the cooking liquor is prepared on a single PDB (according to the prototype). After cooking, the yield is determined

the degree of delignification and physico-mechanical indicators of cellulose,

The data presented in table 1.

EXAMPLE 2 The preparation of the cooking liquor and the soda cooking are carried out as described in Example 1, but spruce wood chips are subjected to cooking.

The data presented in table 2.

Example The method is carried out analogously to example 1, but dissolving sodium hydroxide is in PDB to an active alkali content of 15% of the mass of as., And birch wood chips are subjected to cooking.

Suburban presented in Table 3.

Example 4, A cooking solution was prepared by dissolving a mixture of sodium hydroxide and sodium sulfide in PDB to an active alkali content of 14% by weight as. and sulphidity 26%. The flow rate of the added polyacrylamide is 0.05-0.20% by weight of a.s.

Birch wood chips are subjected to sulphate cooking in a manner similar to Example 1 for soda cooking.

The data presented in table 3,

EXAMPLE 5 The preparation of the cooking liquor is carried out analogously to Example 4, but the dissolution of the mixture of sodium hydroxide and sodium sulfide is carried out until

0

active alkali is 17% of the mass of A..s., and sulphate cooking is subjected to chips from spruce.y wood.

The data presented in table 2.

Example 6: The method of implementation is the same as Example 5, but pine wood chips are subjected to cooking.

The data presented in table 1.

From the data presented in Tables 1-3, it can be seen that the proposed method allows, in comparison with the prototype method, to reduce the content of resinous substances and lack of penetration in cellulose, as well as to increase the yield of cellulose and its physical and mechanical properties.

Claims (1)

The invention of the method of preparing a cooking liquor for the production of cellulose by dissolving sodium hydroxide or a mixture of it with sodium sulfide in a post-yeast brew of hydrolysis production, characterized in that, in order to reduce the content of resinous substances and lack of penetration in cellulose, while simultaneously increasing its yield and physico-mechanical parameters After dissolving, polyacrylamide in the amount of 0.05-0.20% by weight of absolutely dry wood chips required for cooking is additionally introduced into the resulting solution. % - m 0.050,100.20 43.8 44,346,1 46,546,6 0.8 30.6 0.760 7800 8.5 1580 0.8 30.2 0.480 8000 9.0 1700 0.750, W 700.4 30.1 0.420 9880 9.0 1750 30.0 0.415 9000 9,2 1750 31,8 0.560 10200 8.6 1780 Table 1 46.6 0.4 31,8 0.560 102000 8.6 1780 0.05 47.1  0.35 31.0 0.380 10300 1800 Oh 10 47.9 0.30 31.2 0.345 10500 8.7 1820 0.20 48.2 0.25 31.0 0.345 11000 8,9 1900 table 2