CN111101397A - Preparation process of grey white board paper bottom pulp - Google Patents
Preparation process of grey white board paper bottom pulp Download PDFInfo
- Publication number
- CN111101397A CN111101397A CN201911398683.XA CN201911398683A CN111101397A CN 111101397 A CN111101397 A CN 111101397A CN 201911398683 A CN201911398683 A CN 201911398683A CN 111101397 A CN111101397 A CN 111101397A
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- Prior art keywords
- pulp
- pulping
- waste
- grey
- board
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Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
- D21H11/00—Pulp or paper, comprising cellulose or lignocellulose fibres of natural origin only
- D21H11/14—Secondary fibres
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21B—FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT
- D21B1/00—Fibrous raw materials or their mechanical treatment
- D21B1/04—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres
- D21B1/12—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres by wet methods, by the use of steam
- D21B1/30—Defibrating by other means
- D21B1/32—Defibrating by other means of waste paper
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21B—FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT
- D21B1/00—Fibrous raw materials or their mechanical treatment
- D21B1/04—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres
- D21B1/12—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres by wet methods, by the use of steam
- D21B1/30—Defibrating by other means
- D21B1/34—Kneading or mixing; Pulpers
- D21B1/345—Pulpers
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/1026—Other features in bleaching processes
- D21C9/1036—Use of compounds accelerating or improving the efficiency of the processes
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/1057—Multistage, with compounds cited in more than one sub-group D21C9/10, D21C9/12, D21C9/16
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/1084—Bleaching ; Apparatus therefor with reducing compounds
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/16—Bleaching ; Apparatus therefor with per compounds
- D21C9/163—Bleaching ; Apparatus therefor with per compounds with peroxides
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21D—TREATMENT OF THE MATERIALS BEFORE PASSING TO THE PAPER-MAKING MACHINE
- D21D5/00—Purification of the pulp suspension by mechanical means; Apparatus therefor
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/64—Paper recycling
Abstract
The invention relates to the technical field of papermaking, in particular to a preparation process of grey white board bottom pulp, which comprises pulping, purifying and screening, bleaching and pulping, wherein the deinked pulp board is used for replacing waste newspaper, the deinked pulp board has longer fiber, lower ash content, better devillicate brooming and reasonable freeness of finished pulp, can reduce the ash content, residual ink content and stickies content in the pulp, has high cleanliness of the bottom pulp, and each papermaking index of the pulp is in the process requirement range, thereby reducing the phenomena of paper surface hole breaking and paper breaking caused by the pulp problem; the addition of bleaching agent in the pulp can obviously improve the whiteness of the pulp. The process method is simple and suitable for large-scale production.
Description
Technical Field
The invention relates to the technical field of papermaking, in particular to a preparation process of grey-bottom white board bottom pulp.
Background
Because the control to imported waste paper is stricter at present, domestic waste paper fibre is worsen day by day, and the fibre is shorter and shorter, and the crystallinity is higher and higher, and the pulping freeness is lower and lower, and along with the appearance of all kinds of paper fillers, the waste paper ash content is higher and higher, has produced very big challenge to present waste paper papermaking technology. Meanwhile, the market of domestic waste paper purchasing does not form certain standards and specifications, the price change is large, the supply quantity of waste paper fluctuates, and the condition of insufficient supply of white waste paper often appears.
At present, waste newspaper is generally used as a raw material for white board bottom pulp with an ash bottom, so that the problem of large ink amount in an ink removing pulp line is caused, two sections of flotation and one section of thermal dispersion are needed to effectively remove ink stickies, only one section of flotation and one section of thermal dispersion are needed for an old pulp line, the residual ink in the pulp is high, the ink stickies on a scraper of a paper machine dryer are more, and various problems of paper machine hole breaking, paper breaking and the like can be caused in serious cases.
Disclosure of Invention
The invention aims to provide a preparation process of grey-bottom white board bottom pulp, which can solve the problem of hole breaking and paper breaking caused by much residual ink in the bottom pulp.
In order to achieve the purpose, the invention adopts the following technical scheme:
the preparation process of the grey white board paper bottom pulp comprises the following steps:
step one, pulping: sending the waste paper to a pulper through a chain plate machine for pulping to obtain raw pulp;
step two, purifying and screening: removing impurities from the primary pulp obtained in the step one through a slag remover, a coarse screen, a fine screen and flotation to obtain fine pulp;
step three, bleaching: then the good pulp obtained in the step two is concentrated by a multi-disc concentrator and then bleached;
step four, pulping: and thermally dispersing the bleached pulp, and then carrying out disc grinding and pulping to obtain the grey-bottom white board bottom pulp.
In the technical scheme, in the first step, the waste paper is prepared from the following raw materials in parts by weight: 50 to 70 percent of national waste, 10 to 30 percent of daily waste and 10 to 30 percent of deinked pulp board.
Specifically, the waste paper in the first step is prepared from the following raw materials in parts by weight: 60% of domestic waste, 20% of daily waste and 20% of deinked pulp board.
In the technical scheme, in the third step, the good pulp obtained in the second step is sent to a multi-disc concentrator for concentration, then a buffering agent is added into the pulp, an oxidation bleaching agent is added for oxidation bleaching for 25-35 min at 95-100 ℃, then multi-disc concentration is carried out again, and then a reduction bleaching agent is added for reduction bleaching for 20-30 min at 70-80 ℃.
Specifically, the oxidation bleaching agent is hydrogen peroxide.
Specifically, the mass ratio of the reduction bleaching agent to the oxidation bleaching agent is 1: 5-7.
Specifically, the buffer is a combination of sodium hydroxide and sodium sulfite.
The invention has the beneficial effects that:
the preparation process of the grey white board paper bottom pulp provided by the invention comprises pulping, purifying and screening, bleaching and pulping, wherein the deinked pulp board is used for replacing waste newspaper, the deinked pulp board has longer fiber and lower ash content, the fibrillation is better, the freeness of the finished pulp is reasonable, the ash content, the residual ink content and the content of stickies in the pulp can be reduced, the cleanliness of the bottom pulp is high, various papermaking indexes of the pulp are in the process requirement range, the phenomena of paper surface hole breaking and paper breaking caused by pulp problems are reduced, and meanwhile, the deinked pulp board replaces the waste newspaper to ensure that a machine table can stably run under the condition of shortage of traditional waste paper raw materials; the addition of bleaching agent in the pulp can obviously improve the whiteness of the pulp. The process method is simple and suitable for large-scale production.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects solved by the present invention more apparent, the present invention is further described in detail below with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
Example 1.
The preparation process of the grey white board paper bottom pulp comprises the following steps:
step one, pulping: sending 60% of national waste, 20% of daily waste and 20% of deinked pulp board in parts by weight to a pulper through a chain plate machine for pulping to obtain raw pulp;
step two, purifying and screening: removing impurities from the primary pulp obtained in the step one through a slag remover, a coarse screen, a fine screen and flotation to obtain fine pulp;
step three, bleaching: then the good pulp obtained in the second step is sent to a multi-disc concentrator for concentration, then buffer sodium hydroxide and sodium sulfite are added into the pulp, then an oxidation bleaching agent hydrogen peroxide is added for oxidation bleaching for 30min at the temperature of 98 ℃, then multi-disc concentration is carried out again, and then a reduction bleaching agent is added for reduction bleaching for 25min at the temperature of 75 ℃, wherein the mass ratio of the reduction bleaching agent to the oxidation bleaching agent is 1: 6;
step four, pulping: and thermally dispersing the bleached pulp, and then carrying out disc grinding and pulping to obtain the grey-bottom white board bottom pulp.
Example 2.
The preparation process of the grey white board paper bottom pulp comprises the following steps:
step one, pulping: sending 50% of national waste, 30% of daily waste and 20% of deinked pulp board in parts by weight to a pulper through a chain plate machine for pulping to obtain raw pulp;
step two, purifying and screening: removing impurities from the primary pulp obtained in the step one through a slag remover, a coarse screen, a fine screen and flotation to obtain fine pulp;
step three, bleaching: then the good pulp obtained in the second step is sent to a multi-disc concentrator for concentration, then buffer sodium hydroxide and sodium sulfite are added into the pulp, then an oxidation bleaching agent hydrogen peroxide is added for oxidation bleaching for 35min at the temperature of 95 ℃, then multi-disc concentration is carried out again, and then a reduction bleaching agent is added for reduction bleaching for 30min at the temperature of 70 ℃, wherein the mass ratio of the reduction bleaching agent to the oxidation bleaching agent is 1: 5;
step four, pulping: and thermally dispersing the bleached pulp, and then carrying out disc grinding and pulping to obtain the grey-bottom white board bottom pulp.
Example 3.
The preparation process of the grey white board paper bottom pulp comprises the following steps:
step one, pulping: sending 70% of domestic waste, 20% of daily waste and 10% of deinked pulp board in parts by weight to a pulper through a chain plate machine for pulping to obtain raw pulp;
step two, purifying and screening: removing impurities from the primary pulp obtained in the step one through a slag remover, a coarse screen, a fine screen and flotation to obtain fine pulp;
step three, bleaching: then the good pulp obtained in the second step is sent to a multi-disc concentrator for concentration, then buffer sodium hydroxide and sodium sulfite are added into the pulp, then an oxidation bleaching agent hydrogen peroxide is added for oxidation bleaching for 25min at the temperature of 100 ℃, then multi-disc concentration is carried out again, and then a reduction bleaching agent is added for reduction bleaching for 20min at the temperature of 80 ℃, wherein the mass ratio of the reduction bleaching agent to the oxidation bleaching agent is 1: 7;
step four, pulping: and thermally dispersing the bleached pulp, and then carrying out disc grinding and pulping to obtain the grey-bottom white board bottom pulp.
Example 4.
The preparation process of the grey white board paper bottom pulp comprises the following steps:
step one, pulping: sending 60% of national waste, 10% of daily waste and 30% of deinked pulp board in parts by weight to a pulper through a chain plate machine for pulping to obtain raw pulp;
step two, purifying and screening: removing impurities from the primary pulp obtained in the step one through a slag remover, a coarse screen, a fine screen and flotation to obtain fine pulp;
step three, bleaching: then the good pulp obtained in the second step is sent to a multi-disc concentrator for concentration, then buffer sodium hydroxide and sodium sulfite are added into the pulp, then an oxidation bleaching agent hydrogen peroxide is added for oxidation bleaching for 33min at the temperature of 96 ℃, then multi-disc concentration is carried out again, and then a reduction bleaching agent is added for reduction bleaching for 27min at the temperature of 73 ℃, wherein the mass ratio of the reduction bleaching agent to the oxidation bleaching agent is 1: 5.5;
step four, pulping: and thermally dispersing the bleached pulp, and then carrying out disc grinding and pulping to obtain the grey-bottom white board bottom pulp.
Example 5.
The preparation process of the grey white board paper bottom pulp comprises the following steps:
step one, pulping: sending 60% of national waste, 15% of daily waste and 25% of deinked pulp board in parts by weight to a pulper through a chain plate machine for pulping to obtain raw pulp;
step two, purifying and screening: removing impurities from the primary pulp obtained in the step one through a slag remover, a coarse screen, a fine screen and flotation to obtain fine pulp;
step three, bleaching: then the good pulp obtained in the second step is sent to a multi-disc concentrator for concentration, then buffer sodium hydroxide and sodium sulfite are added into the pulp, then an oxidation bleaching agent hydrogen peroxide is added for oxidation bleaching for 27min at the temperature of 99 ℃, then multi-disc concentration is carried out again, and then a reduction bleaching agent is added for reduction bleaching for 23min at the temperature of 77 ℃, wherein the mass ratio of the reduction bleaching agent to the oxidation bleaching agent is 1: 6.5;
step four, pulping: and thermally dispersing the bleached pulp, and then carrying out disc grinding and pulping to obtain the grey-bottom white board bottom pulp.
Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the protection scope of the present invention, although the present invention is described in detail with reference to the preferred embodiments, it should be understood by those skilled in the art that modifications or equivalent substitutions can be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.
Claims (7)
1. A preparation process of grey white board paper bottom pulp is characterized by comprising the following steps: the method comprises the following steps:
step one, pulping: sending the waste paper to a pulper through a chain plate machine for pulping to obtain raw pulp;
step two, purifying and screening: removing impurities from the primary pulp obtained in the step one through a slag remover, a coarse screen, a fine screen and flotation to obtain fine pulp;
step three, bleaching: then the good pulp obtained in the step two is concentrated by a multi-disc concentrator and then bleached;
step four, pulping: and thermally dispersing the bleached pulp, and then carrying out disc grinding and pulping to obtain the grey-bottom white board bottom pulp.
2. The process for preparing grey board paper bottom pulp according to claim 1, characterized in that: in the first step, the waste paper is prepared from the following raw materials in parts by weight: 50 to 70 percent of national waste, 10 to 30 percent of daily waste and 10 to 30 percent of deinked pulp board.
3. The process for preparing the grey board paper bottom pulp according to claim 2, characterized in that: in the first step, the waste paper is prepared from the following raw materials in parts by weight: 60% of national waste, 20% of daily waste and 20% of deinked pulp board.
4. The process for preparing grey board paper bottom pulp according to claim 1, characterized in that: and in the third step, the good pulp obtained in the second step is sent to a multi-disc concentrator for concentration, then a buffering agent is added into the pulp, an oxidation bleaching agent is added for oxidation bleaching for 25-35 min at the temperature of 95-100 ℃, then multi-disc concentration is carried out again, and then a reduction bleaching agent is added for reduction bleaching for 20-30 min at the temperature of 70-80 ℃.
5. The process for preparing grey board paper bottom pulp according to claim 4, characterized in that: the oxidation bleaching agent is hydrogen peroxide.
6. The process for preparing grey board paper bottom pulp according to claim 4, characterized in that: the mass ratio of the reduction bleaching agent to the oxidation bleaching agent is 1: 5-7.
7. The process for preparing grey board paper bottom pulp according to claim 4, characterized in that: the buffer is a combination of sodium hydroxide and sodium sulfite.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911398683.XA CN111101397A (en) | 2019-12-30 | 2019-12-30 | Preparation process of grey white board paper bottom pulp |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911398683.XA CN111101397A (en) | 2019-12-30 | 2019-12-30 | Preparation process of grey white board paper bottom pulp |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN111101397A true CN111101397A (en) | 2020-05-05 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201911398683.XA Pending CN111101397A (en) | 2019-12-30 | 2019-12-30 | Preparation process of grey white board paper bottom pulp |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113430869A (en) * | 2021-07-16 | 2021-09-24 | 四川金田纸业有限公司 | Preparation system and method for manufacturing single-sided white board paper by adopting secondary fibers |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102677515A (en) * | 2012-05-28 | 2012-09-19 | 东莞天龙纸业有限公司 | Process for preparing recovered pulp with high whiteness and high cleanliness |
| CN103243599A (en) * | 2013-04-28 | 2013-08-14 | 汕头市松炀纸业有限公司 | Process for recycling and preparing coated white board paper by using waste paper |
| CN105239439A (en) * | 2015-10-14 | 2016-01-13 | 东莞玖龙纸业有限公司 | Method for making environmental-friendly low-quantification high-endurability coated duplex boards with grey backs |
| CN105672054A (en) * | 2016-01-19 | 2016-06-15 | 吉安集团有限公司 | Manila board for red packet paper and preparation method of Manila board for red packet paper |
-
2019
- 2019-12-30 CN CN201911398683.XA patent/CN111101397A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102677515A (en) * | 2012-05-28 | 2012-09-19 | 东莞天龙纸业有限公司 | Process for preparing recovered pulp with high whiteness and high cleanliness |
| CN103243599A (en) * | 2013-04-28 | 2013-08-14 | 汕头市松炀纸业有限公司 | Process for recycling and preparing coated white board paper by using waste paper |
| CN105239439A (en) * | 2015-10-14 | 2016-01-13 | 东莞玖龙纸业有限公司 | Method for making environmental-friendly low-quantification high-endurability coated duplex boards with grey backs |
| CN105672054A (en) * | 2016-01-19 | 2016-06-15 | 吉安集团有限公司 | Manila board for red packet paper and preparation method of Manila board for red packet paper |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113430869A (en) * | 2021-07-16 | 2021-09-24 | 四川金田纸业有限公司 | Preparation system and method for manufacturing single-sided white board paper by adopting secondary fibers |
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Application publication date: 20200505 |
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