Little-chlorine and little-pollution bleaching process for paper pulp biomimetic pretreatment

A pulp bleaching and pretreatment technology, applied in the field of pulp bleaching, to achieve the effects of easy access, improved tear index, and high brightness

Inactive Publication Date: 2009-10-28
KUNMING UNIV OF SCI & TECH
View PDF4 Cites 7 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, it is a new attempt and application to combine imitation enzyme pretreatment with less toxic and less polluting chlorine-free eleme

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

Example Embodiment

[0018] Example 1

[0019] In the pulp with a concentration of 5% by weight, the amount of NaOH is 3.0%, H 2 o 2 Consumption is 1.2%, metal salen consumption is 0.025%, pyridine consumption and metal salen molar ratio are 0.95: 1, O 2 The pressure is 0.17MPa, and the pulp bleaching pretreatment is controlled at a temperature of 65°C to 75°C for 4h to 5h. Then carry out subsequent elemental chlorine-free bleaching treatment. In the chlorine dioxide bleaching section, the chlorine dioxide consumption is 0.2%, the sodium hydroxide and chlorine dioxide consumption ratio is 0.9: 3, the pulp concentration is 10% during treatment, the temperature is 60° C., and the time is 0.5 hours ; In the chelation treatment section, the chelation treatment diethylenetriaminepentaacetic acid consumption is 0.50%, the pulp concentration is 10% during treatment, the temperature is 50°C, and the time is 0.9 hours; in the hydrogen peroxide bleaching section, the sodium hydroxide consumption is 0.70%,...

Example Embodiment

[0020] Example 2

[0021] In the pulp with a concentration of 3% by weight, the amount of NaOH is 2.0%, H 2 o 2 Consumption is 1.0%, metal salen consumption is 0.02%, pyridine consumption and metal salen molar ratio are 0.90: 1, O 2 The pressure is 0.15MPa, and the pulp bleaching pretreatment is controlled at a temperature of 65°C to 75°C for 4h to 5h. Then carry out subsequent elemental chlorine-free bleaching treatment. In the chlorine dioxide bleaching section, the chlorine dioxide consumption is 0.18%, the sodium hydroxide and chlorine dioxide consumption ratio is 0.8:3, the pulp concentration is 9% during treatment, the temperature is 55°C, and the time is 0.4 hours ; In the chelation treatment section, the chelation treatment diethylenetriaminepentaacetic acid consumption is 0.45%, the pulp concentration is 9% during treatment, the temperature is 45°C, and the time is 0.8 hours; in the hydrogen peroxide bleaching section, the sodium hydroxide consumption is 0.68%, sili...

Example Embodiment

[0022] Example 3

[0023] In the pulp with a concentration of 7% by weight, the amount of NaOH is 4.0%, H 2 o 2 Consumption is 1.5%, metal salen consumption is 0.03%, pyridine consumption and metal salen molar ratio are 1: 1, O 2 The pressure is 0.20MPa, and the pulp bleaching pretreatment is controlled at a temperature of 65°C to 75°C for 4h to 5h. Then carry out subsequent elemental chlorine-free bleaching treatment, in the chlorine dioxide bleaching section, the chlorine dioxide consumption is 0.22%, the sodium hydroxide and chlorine dioxide consumption ratio is 1:3, the pulp concentration is 11% during treatment, the temperature is 65°C, and the time is 0.6 hours ; In the chelation treatment section, the chelation treatment diethylenetriaminepentaacetic acid consumption is 0.55%, the pulp concentration is 11% during treatment, the temperature is 55°C, and the time is 1.1 hours; in the hydrogen peroxide bleaching section, the sodium hydroxide consumption is 0.72%, silicon...

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

No PUM Login to view more

Abstract

The invention relates to a little-chlorine and little-pollution bleaching process for paper pulp biomimetic pretreatment, in particular to a little-chlorine element chlorine-free bleaching (ECF) process for the paper pulp biomimetic pretreatment. The process is a novel little-pollution bleaching technology in the paper pulp biomimetic pretreatment and belongs to the technical field of paper making. The process mainly comprises the following steps of: (1) carrying out metal salen biomimetic pretreatment to paper pulp bleaching, wherein metal salen, pyridine, H2O2 and O2 are used for carrying out bleaching pretreatment to oxygen-removal kraft pulp in alkaline condition; and (2) carrying out subsequent little-chlorine and little-pollution bleaching, wherein paper pulp after the biomimetic pretreatment undergoes three-section bleaching treatment, i.e., a chlorine dioxide bleaching section, a chelation treating section and a hydrogen peroxide bleaching section. The process is simple and easy to implement, has remarkable effect and can improve the whiteness and the property of the paper pulp. Compared with the conventional little-chlorine bleaching procedures, the bleaching process uses less chlorine. Compared with the conventional CEH bleaching, the bleaching process can reduce the time for pulping.

Description

technical field [0001] The invention relates to a paper pulp imitative enzyme pretreatment bleaching process with less chlorine and less pollution, belonging to the paper pulp bleaching technology. Background technique [0002] Conventional CEH (chlorination-alkali treatment-hypochlorite bleaching) bleaching of pulp requires a high amount of chlorine for bleaching, high toxicity in wastewater, serious environmental pollution, poor pulping performance, and long refining time. Therefore, the production cost is also higher. [0003] Elemental chlorine-free bleaching has been widely used in the field of pulp bleaching. It is a less-polluting bleaching process with the advantages of good pulping performance and high whiteness. However, in the conventional elemental chlorine-free bleaching process, two or more stages are generally required in the chlorine dioxide bleaching stage, and the amount of chlorine used for bleaching and the toxicity of waste water are relatively high, wh...

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): D21C9/16
Inventor 周学飞刘晶
Owner KUNMING UNIV OF SCI & 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

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap