Method for single section bleaching bamboo/bagasse pulp

A technology of bagasse pulp and bamboo, applied in pulp bleaching, post-treatment of cellulose pulp, pre-treatment of finely split raw materials, etc., can solve the problem of increasing water, electricity, gas, medicine, toxic sewage discharge, and operating costs Increase and other issues, to achieve the effect of improving production efficiency, environmental and social benefits, and short process

Inactive Publication Date: 2005-03-02
SOUTH CHINA UNIV OF TECH
View PDF0 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] At present, the bleaching process and equipment of straw pulp in my country are very backward. Most factories still use H single-stage bleaching, which generally has high chlorine consumption, low whiteness of bleached pulp (only about 70% ISO), low yield, poor strength, Disadvantages such as poor whiteness stability and serious environmental pollution
C-E-H three

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0023] The bleaching process is as follows:

[0024] 1. Pretreat the unbleached pulp with a chelating agent; the dosage of the chelating agent is 0.3% of the dry pulp weight, the processing temperature is 65°C, the processing time is 80 minutes, and the pH is 6;

[0025] 2. Add H separately 2 o 2 , NaOH and Na 2 SiO 3 ;Based on the dry pulp weight, H 2 o 2 The addition amount is 4%, the addition amount of NaOH is 1.5%, and the NaOH 2 SiO 3 The amount added is 4.0%;

[0026] 3. Introduce oxygen for bleaching; keep O 2 The pressure is 0.5Mpa, the bleaching temperature is 100°C, and the treatment time is 90 minutes.

[0027] The chelating agent is diethylenetriaminepentaacetic acid (DTPA).

Embodiment 2

[0029] 1. Pretreat the unbleached pulp with a chelating agent; the dosage of the chelating agent is 0.5% of the dry pulp weight, the processing temperature is 70°C, the processing time is 45 minutes, and the pH is 5;

[0030] 2. Add H separately 2 o 2 , NaOH and Na 2 SiO 3 ;Based on the dry pulp weight, H 2 o 2 The addition amount is 5%, the addition amount of NaOH is 2.5%, and the NaOH 2 SiO 3 The amount added is 4.0%;

[0031] 3. Introduce oxygen for bleaching; keep O 2 The pressure is 0.8Mpa, the bleaching temperature is 80°C, and the treatment time is 75 minutes.

[0032] The chelating agent is ethylenediaminetetraacetic acid (EDTA).

Embodiment 3

[0034] 1. Pretreat the unbleached pulp with a chelating agent; the dosage of the chelating agent is 0.7% of the dry pulp weight, the treatment temperature is 90°C, the treatment time is 20 minutes, and the pH is 4;

[0035] 2. Add H separately 2 o 2 , NaOH and Na 2 SiO 3 ;Based on the dry pulp weight, H 2 o 2 The addition amount is 6.5%, the addition amount of NaOH is 2.5%, and the NaOH 2 SiO 3 The amount added is 4.0%;

[0036] 3. Introduce oxygen for bleaching; keep O 2 The pressure is 1.0Mpa, the bleaching temperature is 110°C, and the treatment time is 40 minutes.

[0037] Described chelating agent is citric acid.

[0038] After the bamboo / bagasse pulp was bleached by the method of Example 2, the result was: the yield of bleached pulp was 93.02%, the whiteness reached 85.07% ISO, the kappa value was 5.60, and the kappa value reduction rate was 68.80%, all obviously high In bleaching without pretreatment or acid pretreatment, and H2 o 2 The consumption of the pro...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
Whitenessaaaaaaaaaa
Login to view more

Abstract

The single section bamboo/bagasse pulp bleaching process includes the following steps: pre-treatment of pulp with chelating agent; adding certain amount of H2O2, NaOH and Na2SiO3; and introducing oxygen to bleach under certain conditions. The single section bamboo/bagasse pulp bleaching process has excellent effect, advanced technological process, short period, low consumption of water, electric power, steam and chemicals and low cost.

Description

technical field [0001] The invention relates to a method for single-stage bleaching of bamboo / bagasse pulp, specifically a method for pretreating with a chelating agent, and then bleaching bamboo / bagasse pulp through the joint action of hydrogen peroxide and oxygen in a pressurized environment . Background technique [0002] my country is the main producer of bamboo in the world. There are 39 genera and more than 500 kinds of bamboo in my country, with an annual output of about 20 million tons of bamboo. Bamboo has the advantages of high fiber content, long fiber length, and can replace some coniferous wood fibers. It is a raw material with the highest value for pulping and papermaking among gramineous raw materials. my country is also a big sugar producing country in the world, with about 5.4 million tons of bagasse per year, of which about 3 million tons can be used for papermaking; moreover, bagasse is a by-product of sugar factories, which has the advantages of concentr...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): D21C1/00D21C9/10D21C9/147D21C9/16
Inventor 邱玉桂陈春霞王帅
Owner SOUTH CHINA UNIV OF TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products