Chemical mechanical pulping process for whole corn stalk

Abstract

The invention relates to a chemical mechanical clean pulping process with whole corn stalk as a raw material. Firstly, the cut corn stalk is subjected to pre-extraction in hot water, after solid-liquid separation, the stalk is squeezed, ground and washed, the washed stalk is subjected to three-section high-concentration normal-pressure slurry grinding after being subjected to pre-impregnating treatment, and high-yield and high-strength chemical mechanical pulp is obtained, wherein the corn stalk is cut in a conventional hay cutter; extraction in hot water is chemical-free heating autocatalyticextraction under normal pressure; the extrusion and grinding process is performed in a double-screw extrusion and grinding machine; pre-impregnation is impregnation with sodium hydroxide under normalpressure; three-section high-concentration normal-pressure slurry grinding is performed in a high-concentration normal-pressure disc mill. The process has the benefits that compared with conventionalcorn stalk pulping processes, the process does not require physical separation of stalks and leaves of the corn stalk and is applicable to pulping of the whole corn stalk, part of non-fiber components are separated while fiber components in raw materials are almost completely reserved, a few chemicals are consumed in the pulping process, the obtained pulp is high in yield and good in strength, and high-pressure environment is avoided in the whole process. Produced waste liquids can be directly used as raw materials for other procedures.

Description

technical field [0001] The invention relates to the technical field of chemical mechanical pulping, in particular to a whole stalk chemical mechanical pulping process of corn stalks. Background technique [0002] my country's fiber resources are in short supply, and the import of waste paper is limited. How to use existing resources to alleviate the huge pressure of raw material shortage is imminent. The development of non-wood pulping can effectively solve the current dilemma. However, the annual output of crop stalks in my country is huge, and corn stalks account for more than one-third of the proportion, but most of them are directly burned, causing serious pollution and waste. There have been some studies on the use of corn stover for pulping. [0003] Chinese patent 200310124000.4 discloses a chlorine-free bleaching pulping process of depilled corn stalks as raw materials, which uses the pith-removed and leaf-removed corn stalk husks as raw materials, cooks and bleac...

AI Technical Summary

Problems solved by technology

[0007] The purpose of the present invention is to provide a pure corn stalk chemical-mechanical pulping process, which avoids the low-efficiency physical separation of bark and leaves, retains most of the fiber components in raw materials, and solves the problem of corn stalk pulping. Low pulp yield, large consumption of chemical solution, and poor physical properties of pulp. At the same time, hot water pre-extraction waste liquid and pre-impregnation waste liquid can also be used as raw materials for other processes, which is conducive to realizing high-value utilization of all components.