Preparation method of straw pulp

A technology for straw pulp and grasses, which is applied in the field of preparation of straw pulp for papermaking, can solve the problems of low extraction rate of black liquor, low pulping efficiency, limited wood resources, etc., and achieves the effect of improving the efficiency of delignification

Inactive Publication Date: 2013-08-21
KUNMING UNIV OF SCI & TECH +1
View PDF3 Cites 6 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, grass fiber raw materials have congenital deficiencies such as many miscellaneous cells and high silicon content, which lead to restrictive problems such as low black liquor extraction rate, serious silicon interference, and low pulping efficiency, which makes the development of grass pulp industry in recent ten years. More and more restrictions have been imposed on the remaining years, and people also hope that wood pulping can eventually replace grass pulping
[0003] However, the actual situation of my country's papermaking fiber raw materials is: wood resources are very limited, which is far from meeting the needs of the papermaking industry, and the hundreds of millions of tons of rice straw and wheat straw left over from the processing of agricultural products each year are used due to many problems in straw pulping. Not to mention the advantages that it should have as a papermaking resource
For example, high-yield semi-chemical pulping and mechanical pulping are difficult to meet people's requirements for paper product quality. Although chemical pulping methods can produce medium and low-end paper products, the yield is relatively low.

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method of straw pulp

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0035] The straw is cut short and dusted, then washed to remove debris and then dehydrated. The dehydrated rice straw is sent into the cooking equipment, and at the same time, the cooking liquid preheated to 80° C. is added and mixed evenly with it, and the weight ratio of the rice straw to the cooking liquid is 1:3.5. The cooking liquid is an aqueous solution of sodium hydroxide and magnesium sulfate, the consumption of sodium hydroxide is 13% of the weight of rice straw, and the consumption of magnesium sulfate is 2% of the weight of rice straw. After the charging is finished, the cooking equipment is sealed, and oxygen is introduced into it to keep the oxygen pressure in the cooking equipment at 0.5 MPa. The cooking equipment is heated, and the rice straw is steamed at 130° C. for 90 minutes with the cooking liquid. After the cooking is finished, pump the black liquor with low temperature and concentration into the system to lower the temperature in the digester below the ...

Embodiment 2

[0038] Repeat Example 1, and the partial reaction parameters are adjusted as follows: the weight ratio of rice straw and cooking liquid is 1:6, wherein the consumption of sodium hydroxide is 20% of rice straw weight, the consumption of magnesium sulfate is 0.7% of rice straw weight, cooking equipment The oxygen pressure in the oven was maintained at 1MPa, the cooking temperature was 90°C, and the cooking time was 240 minutes. After cooking, the slurry is directly sprayed.

[0039]In this example, the various index results of the prepared straw pulp are: fine pulp yield 54.5%, kappa number 7.7, whiteness 59%ISO, viscosity 850mL / g.

Embodiment 3

[0041] The straw is cut short and dusted, then washed to remove debris and then dehydrated. The dehydrated rice straw is sent into the cooking equipment, and at the same time, the cooking liquid preheated to 90° C. is added and mixed evenly with it, and the weight ratio of the straw to the cooking liquid is 1:4. The cooking liquid is an aqueous solution of sodium hydroxide, sodium sulfide and magnesium sulfate, the consumption of sodium hydroxide and sodium sulfide is 16% of the weight of rice straw, and the consumption of magnesium sulfate is 0.25% of the weight of rice straw. After the charging is finished, the cooking equipment is sealed, and the rice straw is precooked at 90° C. for 60 minutes with the cooking liquid. After completing the precooking, feed oxygen into the cooking equipment to keep the oxygen pressure in the cooking equipment at 0.3MPa. Heat the cooking equipment, and cook the rice straw with the cooking liquid at 110° C. for 30 minutes. The subsequent tre...

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
whitenessaaaaaaaaaa
whitenessaaaaaaaaaa
Login to view more

Abstract

The invention discloses a preparation method of straw pulp. The preparation method comprises the steps of: (1) adding straw raw materials and cooking liquor into cooking equipment according to the weight ratio being (1:3)-(1:6) and evenly mixing, and then sealing then cooking equipment, wherein the cooking liquor contains alkali; (2) introducing oxygen into the sealed cooking equipment to keep the oxygen pressure in the cooking equipment be 0.3-1.0MPa, and cooking the straw raw materials at 90-130 DEG C for 30-240 minutes by using the cooking liquor; and (3) washing and screening pulp obtained after the cooking process is completed. By adopting the preparation method of the straw pulp, provided by the invention, the advantages of the straw raw materials can be fully achieved, and the straw pulp with low hardness, high yield and good quality can be obtained.

Description

technical field [0001] The invention relates to the field of papermaking, in particular to a method for preparing straw pulp for papermaking. Background technique [0002] Grasses (such as straw and wheat straw), as an important class of plant fiber raw materials, have dominated the development of my country's pulp and paper industry in the past few decades, and have a prominent position in the world's non-wood paper industry. However, grass fiber raw materials have congenital deficiencies such as many miscellaneous cells and high silicon content, which lead to restrictive problems such as low black liquor extraction rate, serious silicon interference, and low pulping efficiency, which makes the development of grass pulp industry in recent ten years. More and more restrictions have been imposed on the remaining years, and it is hoped that wood pulping will eventually replace grass-based pulping. [0003] However, the actual situation of my country's papermaking fiber raw ma...

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
Patent Type & Authority Applications(China)
IPC IPC(8): D21C3/02D21C3/22D21H11/12
Inventor 陈克利吴初柱蓝海蓝洋
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