Digesting process for modifying natural bamboo pulp and bleached wood pulp into dissolving pulp by compounding

Abstract

The invention discloses a digesting process for modifying natural bamboo pulp and bleached wood pulp into dissolving pulp by compounding. Composite pulp is fed into a continuous digester for digestion, a continuous digesting tube of the continuous digester has three sections, a section connected with a pre-reaction bin is provided with a T-shaped tube for adding an alkaline solution and a steam tube for adding steam, the other two sections are provided with steam tubes for adding steam, and a liquor ratio is 1:(2.0-4.0); the alkaline solution is NaOH, and is added in an amount which is 17 to 23 percent based on the oven dry weight; and the compression ratio is 1:(2-3.0). Because raw materials are the natural bamboo pulp and the bleached wood pulp, the cost of preparing the dissolving pump is reduced to a large extent; meanwhile, the prepared dissolving pulp meets the requirement for the quality of dissolving pulp for viscose.

Description

technical field [0001] The present invention relates to a method for compound modification of natural bamboo pulp and bleached wood pulp into dissolving pulp, in particular to a method for compound modification of natural color bamboo pulp and bleached wood pulp into dissolving pulp, wherein the dissolving pulp refers to pulp for viscose fiber Meal, cellulose and cellulose derivatives. Background technique [0002] The application number is 200710050470.9, the authorized announcement number is CN101158125, and the authorized announcement date is April 9, 2008. The Chinese invention patent discloses a paper-making grade coniferous wood pulp board modification process, wherein the cooking process uses paper-making grade wood pulp board Use caustic soda method, sulfate method or sulfite method for cooking, and the cooking agents are NaOH, NaOH+Na 2 S, Na 2 SO 3 + NaOH, the process conditions are: 1. The total alkali concentration of the cooking liquid by the caustic soda me...

AI Technical Summary

Problems solved by technology

But the bamboo pulp prepared by this invention has the following disadvantages: 1, the yield is low, and the highest yield is only 85%

2. The α-cellulose content fluctuates greatly, from 85% to 95%, which makes the modified bamboo pulp α-cellulose content unstable

3. The average length of fibers is lower than that of paper-making wood fibers, and the content of ash and polypentose in the production process is high, and the bamboo fibers are hard, have more thick-walled fibers, narrow cell lumens, dense fiber tissues, and the presence of air in the cells leads to dissolution Difficult, large amount of chemicals

4. The viscose fiber produced by a single bamboo pulp has monotonous performance and does not show individuality

But this invention is only applicable to the modification of cotton linters and is prepared into viscose fiber. If the composite material is modified by the method provided by the invention to prepare dissolving pulp, the quality index of the modified dissolving pulp cannot reach that of dissolving pulp. Requirements, and high energy consumption, low yield

[0007] To sum up, the above-mentioned invention patents mainly have the following disadvantages: 1. The raw material is single, and the dissolving pulp produced has single performance and does not show individuality

2. A single raw material has its own disadvantages, such as high production cost, low yield, and unstable product quality

3. Outdated production equipment, high energy consumption, and uneven cooking