SU1288602A1 - Method of determining the yield of wood pulp - Google Patents

Abstract

The invention relates to pulp and paper production and can be used to determine the yield of pulp. The aim of the invention is to improve the accuracy of determining the yield of pulp. In the method described, the concentration of wood pulp in the suspension under study and the volume of filtrate to be taken from a sample of the pulp suspension are measured. Then the filtrate is taken in the amount of 40-60% of the specified volume and return to the filter. The yield of wood pulp is determined taking into account the moisture content of the initial wood pulp, (1- |) - 100 raw materials according to the formula S.- Se (G- |) where P is the yield of wood pulp,%; Wg - the content of dry fiber in the circulating water, g; W is the dry fiber content in the wood pulp suspension, g; S is the dry matter content of wood pulp, g; Sg - dry matter content in the circulating water, g; C is the concentration of the suspension Y., mass,%; B - moisture content of the original wood,%. The pulp can be filtered using a strainer. 1 tab. i (L yu cx 00 O5 o to

Description

I-

The invention relates to pulp and paper production and can be used to determine the yield of pulp.

The purpose of the invention is to improve the accuracy of determining the yield of pulp.

The method of determining the intake is carried out with the help of an instrument with a removable grid, which provides for the selection of the filtrate and return it in an amount of 40-60% for repeated fixing

A suspension of wood pulp and recycled water is fed to the pulverizer from the bath of the grinder.

The tested suspension of wood pulp and recycled water is divided into two samples, the first of which is analyzed for the second dry matter content — the fiber content in the following sequence.

Initially, the content of dry substances in the pulp suspension and circulating water is determined, for which 100 ml of the pulp suspension and circulating water suspension, respectively, are placed in evaporation cups. The temperature of the pulp samples should be (20 ± 3) С Moisture is evaporated in a water bath and the residue is dried in a drying cabinet at () ° С to a constant weight. The mass of dry substances in the suspension of wood pulp and in the circulating water is determined by the formula

 S

hr

5 „S

e.h

where S | ,, and Sg is the dry content

substances in suspension, respectively, wood pulp and circulating water;

8, and - the mass of the dried samples, respectively, wood pulp and circulating water.

The determination is repeated three times. The average result of the three definitions expresses the amount of dry matter in the pulp and in the circulating water 5 "and S.

The dry fiber content of the wood pulp suspension Wrt is then determined.

For the tests, a sample of the fibrous suspension is taken from a volume based on the content of 2 g of absolutely dry matter in it. The sampled mass was diluted with pure water (from 20 ° C), adjusting the volume of the suspension to 1 l. The sample is stirred and poured into a vessel to filter the suspension of the instrument used. After 400-600 ml of filtrate is leaked, it is returned for re-filtration.

Upon completion of the filtration, a removable mesh is removed from the device and the resulting casting is removed. The casting of the pulp is dried in an oven at (105 ± 2) to constant weight. The result results in a suspension volume of 100 ml.

The determination is repeated 3 times. The average result of the three definitions expresses the amount of fiber in the pulp suspension Wf ,. Next, the concentration of solids in the pulp suspension (C) and the fiber content (Wg) in the circulating water are determined by filtering individual samples of 100 g each through paper filters and drying them at (10512) C to a constant weight.

The yield of wood pulp is calculated according to the formula

WH W.

(1 -) in

100

where P is the yield of wood pulp,%; W is the dry fiber content in the wood pulp suspension, g; ;

W is the dry fiber content in the circulating water, g;

SP is the dry matter content in the pulp suspension, g;

S is the dry matter content in circulating water suspension. dy, g;

C is the concentration of wood pulp suspension,%; B - moisture content of the original wood,%.

Examples of determining the yield of pulp are tabulated.

Claims (1)

Invention Formula The method of determining the wood pulp yield, which consists in separating the pulp suspension and circulating water into two samples by separately evaporating the first pulp suspension and circulating water samples to obtain dry matter of the pulp and circulating water and filtering their second samples with subsequent drying of precipitated sediments on filters before obtaining dry fiber, measuring the dry matter and fiber in each sample and calculating the determined value from the measured values, characterized in that, in order to increase Neither the accuracy of the determination, measure the concentration of wood pulp in the suspension under study, the volume of the filter taken from the sample of the pulp suspension and the moisture content of the original wood, and return the initially collected filtrate to re-filtering in the amount of 40-60% of the volume of the filtered sample of wood suspension 11, 3015 1, 1549 0.28750,14871,2405 21,3496 1,1507 0,28150,15311,2031 31,3158 1,1489 0,28530,14861,1744 to Wed 1,3223 1,1515 0,28480,15051,2060 11.2772 1.0863 0.3268 0.16041.0971 21.2513 1,10140,32430,16191,0847 3.1,2965 t, 0915 0.3211 0.16421.1062 Wed.1,2750 1,0911 0,3241 0.16221.0960 filtering of the pulp suspension is carried out through a strainer, and the determination of the yield of pulp is made by the formula w - and „(1 -5) -100 R at - SB (1 - i five 0 five where P is the yield of wood pulp,%; the content of dry fiber in the circulating water, g; the content of dry fiber in the suspension of wood may, sy, g; dry matter content in wood pulp suspension, g; dry matter content in circulating water, g; the concentration of wood pulp in the suspension under study,%; moisture content of the original wood,%. 9 w s s e c 50, 0 0,9759 50.0 0.9759 96.2 50.0 0.9781 50.0 0.9781 97.3 11.5261 1.3098 0.3250 0.1745 1.3370 21.4782 1.2893 0.3227 0.1637 1.3011 31.5200 1.3009 0.3256 0.1716 1.2913 sr, 5081 1.3000-0.3244 0.1716 1.3098 11.2896 1.0381 0.32711.1404 1.0882 21.2852 1.1933 0.32420.1492 1.0767 3.1.2915 1.0506 0.32460.1507 1.0945 Wed.1,2887 1,0940 0,32530,1467 1,0864 Editor O. Bugir Compiled by N. Nikolsky Tehred V. KadarKorrektor l. Patay Order 7802/43 Circulation 799 Subscription VNIIPI USSR State Committee on affairs of inventions and discoveries 113035 ,, Moscow, Zh-35, Raushsk nab. 4/5 Production and printing company, Uzhgorod, st. Project, 4 Table continuation 50.0 0.9738 50.0 0.9738 95.9 50.0 0.9783 50.0 0.9783 97.9