CN100412267C - Method for bleaching middle and thick paper pulp by hydrogen peroxide and through double bleaching tower - Google Patents
Method for bleaching middle and thick paper pulp by hydrogen peroxide and through double bleaching tower Download PDFInfo
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- CN100412267C CN100412267C CNB200610035316XA CN200610035316A CN100412267C CN 100412267 C CN100412267 C CN 100412267C CN B200610035316X A CNB200610035316X A CN B200610035316XA CN 200610035316 A CN200610035316 A CN 200610035316A CN 100412267 C CN100412267 C CN 100412267C
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Abstract
The present invention discloses a method for bleaching middle and thick paper pulp by hydrogen peroxide through double bleaching towers. The method comprises: paper pulp is washed and concentrated; 0.5 to 1.5% of NaOH, 0.5 to 3% of sodium silicate, 0.05 to 0.5% of magnesium sulfate and 1.0 to 2.5% of hydrogen peroxide, etc. by absolute dry pulp weight are added, and the paper pulp is heated to 70 to 100 DEG C; the Number 1 bleaching tower carries out bleaching reaction for 30 to 90 minutes at the temperature of 70 to 100 DEG C; the Number 2 bleaching tower carries out bleaching reaction for 30 to 90 minutes by maintaining the temperature of 70 to 100 DEG C, and 0.5 to 1.5% of hydrogen peroxide and a proper amount of bleaching assistant are additionally added; the paper pulp is diluted by adding water and washed to obtain bleached pulp. The whiteness increment is from 25 to 30%ISO after the paper pulp is bleached; the whiteness is more than 88%ISO after the paper pulp is bleached by the method; as compared with the increment of the prior art, the whiteness of the bleached pulp is increased by 3 to 4%ISO, the quality of bleached pulp paper can be increased, and the production cost is reduced.
Description
Technical field
The present invention relates to the dioxde pulp bleaching process of pulp and paper industry, more particularly relate to a kind of hydrogen peroxide of middle concentration paper pulp efficiently double tower method for bleaching of wooden class, bamboo class, reed reed class, careless class paper pulp.
Background technology
The existing dioxde pulp bleaching process of China mainly is to be the method for bleaching agent with chlorine, method with elemental chlorine and hypochlorite bleaching, produce the toxic waste of a large amount of with serious pollution organic chlorides, wastewater flow rate is big, wastewater biochemical is handled can not solve wastewater toxicity fully, and of poor quality behind the association with pulp bleaching, and yellowing reversion of pulp is serious, physical strength is poor, can not float paramount whiteness.Therefore, the hydrogen peroxide bleaching replacement chlorine that development nothing (lacking) is polluted floats and becomes trend.But, hydrogen peroxide bleaching efficiency is not high, existing single hop list tower method for bleaching, the increment of bleaching whiteness can only be about 20%, final whiteness reaches 82～85%ISO, make chemical pulp adopt hydrogen peroxide bleaching not reach higher whiteness 88% and above requirement, can not meet the requirement of high whiteness commercial pulp.
Summary of the invention
The objective of the invention is to overcome the deficiency of existing single hop list tower hydrogen peroxide bleaching technology, a kind of hydrogen peroxide of middle concentration paper pulp efficiently double tower method for bleaching is provided, do not increase in chemicals consumption under the situation that (even slightly reduce), reaction time do not increase, increase bleaching back pulp brightness 3～4%, reach the whiteness of 88%ISO, whiteness increment 25～30%ISO behind the association with pulp bleaching.
The present invention is applicable to the middle concentration paper pulp bleaching of scales such as 50 ton per days, 100 ton per days, 150 ton per days, 200 ton per days, 300 ton per days, 400 ton per days.
The object of the invention is achieved through the following technical solutions:
A kind of middle concentration paper pulp hydrogen peroxide double tower method for bleaching, its feature comprises the steps and process conditions:
Following % consumption is all by oven dry stock weight,
(1) pulp washing concentrates
The low-consistency stock of 2～4% (weight) is pumped into vacuum pulp washing machine, and after washing concentrating, pulp density is brought up to 10～14% (weight), falls in the conveying worm that is installed on below the Water Extraction Machinery;
(2) add bleaching assistant
0.5～1.5% the NaOH, 0.5～3% sodium metasilicate, 0.05～0.5% magnesium sulfate and 0～0.3% EDTA (or DTPA) bleaching assistant that in the paper pulp of the conveying worm of step (1), add oven dry stock weight, paper pulp is fallen in the storage slurry standpipe of middle underflow pump, dense blender during paper pulp delivers into by middle underflow pump subsequently, in paper pulp enters before the dense blender or in be incorporated as 1.0～2.5% hydrogen peroxide of oven dry stock weight in the dense blender, and feeding steam, it is 70～100 ℃ that paper pulp is heated to temperature;
(3) 1# bleaching tower bleaching
Step (2) gained paper pulp entered from 1# hydrogen peroxide bleaching tower (upflow tower) end, and paper pulp is 70～100 ℃ at the bleaching tower interior reaction temperature, and the reaction time is 30～90 minutes, discharges from cat head subsequently;
(4) 2# bleaching tower bleaching
The paper pulp of discharging from 1# bleaching cat head is added 0～0.75% NaOH into oven dry stock weight, 0～1.0% sodium metasilicate, 0～0.25% magnesium sulfate bleaching assistant and 0.5～1.5% hydrogen peroxide, by in dense blender mix, enter the cat head (downflow tower) of 2# bleaching tower then, bleaching temperature is 70～100 ℃ in its tower, normal pressure, the reaction time is 30～90 minutes;
(5) paper pulp is after the 2# bleaching tower reacts end, and paper pulp is being discharged behind (downflow tower) thin up at the bottom of the tower, and gets bleached pulp after washing (or neutralization washing).
Useful is, described step (5) is specially, and paper pulp is after the reaction of 2# bleaching tower finishes, and paper pulp adds dilution water at the bottom of the tower, and to be diluted to slurry dense 3%, discharges with pump, is pumped to the vacuum pulp washing machine washing then, after the washing bleached pulp.
The consumption explanation of bleaching chemical:
The addition of bleaching assistant and hydrogen peroxide (to oven dry stock weight meter) is as shown in table 1:
Table 1
| The 1# bleaching tower | The 2# bleaching tower | |
| Alkali (NaOH) | 0.5～1.5％ | 0～0.75％ |
| Sodium metasilicate | 0.5～3.0％ | 0～1.0％ |
| Magnesium sulfate | 0.05～0.5％ | 0～0.25％ |
| EDTA (or DTPA) | 0～0.3％ | 0 |
| Hydrogen peroxide (H 2O 2100%) | 1.0～2.5％ | 0.5～1.5％ |
Useful is that the paper pulp of the present invention's bleaching is wooden class, bamboo class, reed reed class, careless class paper pulp, specifically is wooden class chemical pulp, semi-chemical pulp, change machine slurry, mechanical pulp; Bamboo class chemical pulp, semi-chemical pulp; Reed reed class chemical pulp, semi-chemical pulp; Grass class chemical pulp, semi-chemical pulp etc.
The present invention compares with existing method, has following advantage:
(1) when reaching identical bleached pulp whiteness, the total amount of used bleaching assistant of the present invention and hydrogen peroxide can descend 20～30%, thereby reduces production costs greatly.
(2) adopt method for bleaching of the present invention and existing hydrogen peroxide bleaching method to produce institute's bleaching assistant that uses and bleaching total time identical with the hydrogen peroxide consumption when identical, the increment of bleached pulp whiteness increases by 3～4%ISO, starches the paper quality raising after bleaching.
(3) adopt method bleaching effect of the present invention to approach the effect of two sections of existing methods, thereby make investment reduce 40～50%, production cost descends more than 30%.Discharge wastewater flow rate in the production and reduce half, bleaching effluent is nontoxic.
The specific embodiment
The present invention is further illustrated below by embodiment, but the scope of protection of present invention is not limited to the scope of embodiment statement.
Embodiment 1
Produce the 150 tons of efficient middle concentration paper pulp hydrogen peroxide of bamboo chemical pulp double tower bleachings daily, paper pulp is through delignification, necessarily bleaching and preliminary treatment before the hydrogen peroxide bleaching, and pulp brightness is 62%ISO.
(1) the bamboo class chemical pulp that the about 62%ISO of whiteness is handled through front bleaching is pumped to vacuum pulp washing machine with weight concentration 4%, more than washing concentrating to 13% weight concentration after, fall in the conveying worm that is installed on below the Water Extraction Machinery about 50 ℃ of paper pulp temperature.
(2) in the paper pulp of step (1) conveying worm, add the NaOH of 0.75% (in oven dry stock weight), the sodium metasilicate of 0.5% (in oven dry stock weight), the magnesium sulfate of 0.25% (in oven dry stock weight), the EDTA of 0.1% (in oven dry stock weight), paper pulp falls into middle underflow pump storage slurry standpipe after preliminary the mixing, during paper pulp delivers into by middle underflow pump subsequently in the dense blender, in paper pulp enters, add hydrogen peroxide 1.5% (in oven dry stock weight) before the dense blender and feed steam, paper pulp is heated to 100 ℃ of temperature.
(3) step (2) gained paper pulp entered from 1# bleaching tower (upflow tower) end, and the tower interior reaction temperature remains on 100 ℃, and normal pressure reacted 60 minutes, and paper pulp is discharged from cat head subsequently.
(4) paper pulp of discharging from 1# bleaching cat head is added the magnesium sulfate and the steam of the NaOH, 0.75% (in oven dry stock weight) of hydrogen peroxide 1.5% (in oven dry stock weight), 0.75% (in oven dry stock weight), mix by dense blender in, enter 2# bleaching tower cat head (downflow tower) then, 100 ℃ of its tower interior reaction temperatures, 90 minutes time.
(5) paper pulp pulp brightness when the reaction of 2# bleaching tower finishes can reach 88%ISO, adding dilution water at the bottom of 2# bleaching Tata is diluted to the dense 3% usefulness pump of slurry and discharges, pulp pump is delivered to vacuum pulp washing machine washing, washes the after bleaching slurry and enters pulp storage tower and store and send paper machine room or pulpboard workshop to manufacture paper with pulp.
The selected capital equipment of present embodiment is as follows:
A, float before pulp washing concentrate and float the back used vacuum pulp washing machine of washing and be 35m
2, be the product of Shandong Wenrui Machinery Manufacture Co., Ltd., Anqiu;
B, middle underflow pump are the SF100-250 type, lift 60m, and Foshan is agree richness and is come Co., Ltd's product;
C, in dense blender be the ZH-12 type, melting concn 8～15%, the papermaking of Guangdong South China Science ﹠ Engineering University with pollute control national project research center and make;
D, hydrogen peroxide bleaching tower (total measurement (volume) 150m
3, non-standard equipment), manufacture and design by papermaking of Guangdong South China Science ﹠ Engineering University and pollution control national project research center.
Embodiment 2
Produce the 150 tons of efficient middle concentration paper pulp hydrogen peroxide of wheat straw chemical pulp double tower bleachings daily, paper pulp is through delignification, necessarily bleaching and preliminary treatment before the hydrogen peroxide bleaching, and pulp brightness is 65%ISO.
(1) the about 65%ISO of wheat straw chemical pulp whiteness that handles through the front bleaching is pumped to vacuum pulp washing machine with weight concentration 2%.After pulp washing is concentrated into 10% weight concentration, fall into the conveying worm that is installed on below the Water Extraction Machinery, about 50 ℃ of paper pulp temperature.
(2) in the paper pulp of step (1) conveying worm, add NaOH 0.5% (in oven dry stock weight), sodium metasilicate 2% (in oven dry stock weight), EDTA0.2% (in oven dry stock weight), magnesium sulfate 0.05% (in oven dry stock weight), paper pulp falls into middle underflow pump storage slurry standpipe after preliminary the mixing, dense blender during paper pulp delivers into by the middle concentration paper pulp pump subsequently, in paper pulp enters, add hydrogen peroxide 1.0% (in oven dry stock weight) before the dense blender, feed and be steam heated to 70 ℃ of temperature.
(3) step (2) gained paper pulp entered from 1# bleaching tower (upflow tower) end, and the tower interior reaction temperature remains on 70 ℃, normal pressure, and the reaction time is 30 minutes, paper pulp is discharged from cat head subsequently.
(4) paper pulp of discharging from the 1# bleaching tower is added hydrogen peroxidase 10 .5% (in oven dry stock weight), 0.4% NaOH (in oven dry stock weight), 1% sodium metasilicate (in oven dry stock weight) and steam, mix by dense blender in, enter 2# bleaching tower cat head (downflow tower) then, 70 ℃ of its tower interior reaction temperatures, 90 minutes time.
(5) paper pulp is when the reaction of 2# bleaching tower finishes, pulp brightness can reach 88%ISO, add dilution water dilution bleached pulp and discharge to starching dense 3% usefulness pump at the bottom of 2# bleaching Tata, pulp pump is delivered to the vacuum pulp washing machine washing, washes the after bleaching slurry and enters pulp storage tower and store and send paper machine room or pulpboard workshop to manufacture paper with pulp.
The selected capital equipment of present embodiment is as follows:
Paper pulp concentrates and bleaches the back used vacuum pulp washing machine of washing and is 50m before A, the bleaching
2, be the product of Shandong Wenrui Machinery Manufacture Co., Ltd., Anqiu;
B, middle concentration paper pulp pump are the SF100-250 type, lift 60m, and Foshan is agree richness and is come Co., Ltd's product;
C, in dense blender be the ZH-12 type, melting concn 8～15%, the papermaking of Guangdong South China Science ﹠ Engineering University with pollute control national project research center and make;
D, hydrogen peroxide bleaching tower (total measurement (volume) 150m
3, non-standard equipment), manufacture and design by papermaking of Guangdong South China Science ﹠ Engineering University and pollution control national project research center.
Embodiment 3
Produce 200 tons of Eucalyptus machines daily and starch efficient middle concentration paper pulp hydrogen peroxide double tower bleaching, paper pulp is through delignification, necessarily bleaching and preliminary treatment before the hydrogen peroxide bleaching, and pulp brightness is 60%ISO.
(1) the Eucalyptus machine of whiteness 60%ISO slurry after the preliminary treatment, is pumped to vacuum pulp washing machine with weight concentration 3% before overbleach.After pulp washing is concentrated into 14% weight concentration, fall into the conveying worm that is installed on below the Water Extraction Machinery wash engine, about 50 ℃ of paper pulp temperature.
(2) in the paper pulp of step (1) conveying worm, add NaOH 1.5% (in oven dry stock weight), sodium metasilicate 3% (in oven dry stock weight), magnesium sulfate 0.2% (in oven dry stock weight), DTPA0.3% (in oven dry stock weight), paper pulp is after preliminary the mixing, fall into middle underflow pump storage slurry standpipe, dense blender during paper pulp delivers into by the middle concentration paper pulp pump subsequently, in entering, paper pulp adds hydrogen peroxide 2.5% (in oven dry stock weight) before the dense blender, feeding is steam heated to 90 ℃ of temperature, enters the 1# bleaching tower then.
(3) step (2) gained paper pulp entered from 1# bleaching tower (upflow tower) end, and the tower interior reaction temperature remains on 90 ℃, normal pressure, and the reaction time is 90 minutes, paper pulp is discharged from cat head subsequently.
(4) paper pulp of discharging from the 1# bleaching tower is added hydrogen peroxide 1.0% (in oven dry stock weight), magnesium sulfate 0.05% (in oven dry stock weight) and steam, mix by dense blender in, enter 2# bleaching tower cat head (downflow tower) then, 90 ℃ of its tower interior reaction temperatures, 30 minutes time.
(5) paper pulp is when the reaction of 2# bleaching tower finishes, pulp brightness can reach 88%ISO, add dilution water dilution bleached pulp and discharge to starching dense 3% usefulness pump at the bottom of 2# bleaching Tata, pulp pump is delivered to the vacuum pulp washing machine washing, washes the after bleaching slurry and enters pulp storage tower and store and send paper machine room or pulpboard workshop to manufacture paper with pulp.
The selected capital equipment of present embodiment is as follows:
A, float before paper pulp concentrate and float the back used vacuum pulp washing machine of washing and be 45m
2, be the product of Shandong Wenrui Machinery Manufacture Co., Ltd., Anqiu;
B, middle underflow pump are the SF100-250 type, lift 60m, and Foshan is agree richness and is come Co., Ltd's product;
C, in dense blender be the ZH-12 type, melting concn 8～15%, the papermaking of Guangdong South China Science ﹠ Engineering University with pollute control national project research center product;
D, hydrogen peroxide bleaching tower (total measurement (volume) 150m
3, non-standard equipment), manufacture and design by papermaking of Guangdong South China Science ﹠ Engineering University and pollution control national project research center.
Embodiment 4
Produce 200 tons of reedization machines daily and starch efficient middle concentration paper pulp hydrogen peroxide double tower bleaching, paper pulp is through delignification, necessarily bleaching and preliminary treatment before the hydrogen peroxide bleaching, and pulp brightness is 63%ISO.
(1) the Eucalyptus machine of whiteness 63%ISO slurry after the preliminary treatment, is pumped to vacuum pulp washing machine with weight concentration 2% before overbleach.After pulp washing is concentrated into 12% weight concentration, fall into the conveying worm that is installed on below the Water Extraction Machinery wash engine, about 50 ℃ of paper pulp temperature.
(2) in the paper pulp of step (1) conveying worm, add NaOH 1.0% (in oven dry stock weight), sodium metasilicate 1% (in oven dry stock weight), magnesium sulfate 0.5% (in oven dry stock weight), through tentatively sneaking into, fall into middle underflow pump storage slurry standpipe, dense blender during paper pulp delivers into by the middle concentration paper pulp pump subsequently adds hydrogen peroxide 1.2% (in oven dry stock weight) before the dense blender in paper pulp enters, feeding is steam heated to 80 ℃ of temperature, enters the 1# bleaching tower then.
(3) the 1# bleaching tower is a upflow tower, and the reed pulp after mixing with medicine enters at the bottom of the 1# bleaching tower, and the tower interior reaction temperature remains on 80 ℃, normal pressure, and the reaction time is 50 minutes, paper pulp is discharged from cat head subsequently.
(4) paper pulp of discharging from the 1# bleaching tower is added hydrogen peroxidase 10 .8% (in oven dry stock weight) and steam, mixes by dense blender in, enters 2# bleaching tower cat head (downflow tower) then, 80 ℃ of its tower interior reaction temperatures, 70 minutes time.
(5) paper pulp is when the reaction of 2# bleaching tower finishes, pulp brightness can reach 88%ISO, add dilution water dilution bleached pulp and discharge to starching dense 3% usefulness pump at the bottom of 2# bleaching Tata, pulp pump is delivered to the vacuum pulp washing machine washing, washes the after bleaching slurry and enters pulp storage tower and store and send paper machine room or pulpboard workshop to manufacture paper with pulp.
The selected capital equipment of present embodiment is as follows:
A, float before paper pulp concentrate and float the back used vacuum pulp washing machine of washing and be 50m
2, be the product of Shandong Wenrui Machinery Manufacture Co., Ltd., Anqiu;
B, middle underflow pump are the SF100-250 type, lift 60m, and Foshan is agree richness and is come Co., Ltd's product;
C, in dense blender be the ZH-12 type, melting concn 8～15%, the papermaking of Guangdong South China Science ﹠ Engineering University with pollute control national project research center product;
D, hydrogen peroxide bleaching tower (total measurement (volume) 200m
3, non-standard equipment), manufacture and design by papermaking of Guangdong South China Science ﹠ Engineering University and pollution control national project research center.
Can see that from the foregoing description paper pulp more than the whiteness 88%ISO, has bigger must the raising than existing single tower method for bleaching, and helps environmental protection after middle concentration paper pulp hydrogen peroxide double tower method for bleaching bleaching of the present invention, cost is lower, has market prospects preferably.
Claims (3)
1. middle concentration paper pulp hydrogen peroxide double tower method for bleaching, its feature comprises the steps and process conditions:
Following % consumption is all by oven dry stock weight;
(1) pulp washing concentrates
The low-consistency stock of 2～4% (weight) is pumped into vacuum pulp washing machine, and after washing concentrating, pulp density is brought up to 10～14% (weight), falls in the conveying worm that is installed on below the Water Extraction Machinery;
(2) add bleaching assistant
0.5～1.5% the NaOH, 0.5～3% sodium metasilicate, 0.05～0.5% magnesium sulfate and 0～0.3% EDTA or the DTPA bleaching assistant that in the paper pulp of the conveying worm of step (1), add oven dry stock weight, paper pulp is fallen in the storage slurry standpipe of middle underflow pump, dense blender during paper pulp delivers into by middle underflow pump subsequently, in paper pulp enters before the dense blender or in be incorporated as 1.0～2.5% hydrogen peroxide of oven dry stock weight in the dense blender, and feeding steam, it is 70～100 ℃ that paper pulp is heated to temperature;
(3) 1# bleaching tower bleaching
Step (2) gained paper pulp enters at the bottom of 1# hydrogen peroxide up-flow bleaching tower, and paper pulp is 70～100 ℃ at the bleaching tower interior reaction temperature, and the reaction time is 30～90 minutes, discharges from cat head subsequently;
(4) 2# bleaching tower bleaching
The paper pulp of discharging from 1# up-flow bleaching cat head is added 0～0.75% NaOH into oven dry stock weight, 0～1.0% sodium metasilicate, 0～0.25% magnesium sulfate bleaching assistant and 0.5～1.5% hydrogen peroxide, by in dense blender mix, enter the cat head that the stream bleaching tower falls in 2# then, bleaching temperature is 70～100 ℃ in its tower, normal pressure, the reaction time is 30～90 minutes;
(5) paper pulp falls after stream bleaching tower reaction finishes at 2#, and paper pulp falls at the bottom of the stream bleaching tower from 2# discharges behind the thin up, and after washing bleached pulp.
2. according to the described middle concentration paper pulp hydrogen peroxide of claim 1 double tower method for bleaching, it is characterized in that described step (5) is specially, paper pulp is after stream bleaching tower reaction end falls in 2#, paper pulp adds dilution water at the bottom of the tower and is diluted to slurry dense 3%, discharge with pump, be pumped to the vacuum pulp washing machine washing then, get bleached pulp after the washing.
3. according to the described middle concentration paper pulp hydrogen peroxide of claim 1 double tower method for bleaching, it is characterized in that the paper pulp of described bleaching is wooden class, bamboo class, reed reed class or careless class paper pulp.
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Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JP4822456B2 (en) * | 2007-02-15 | 2011-11-24 | ウエスチングハウス・エレクトリック・カンパニー・エルエルシー | Removal of second phase particle deposits of niobium from pickled zirconium-niobium alloy |
| CN102251427B (en) * | 2011-07-28 | 2012-12-05 | 华南理工大学 | Two-stage high-efficiency bleaching method for poplar chemical-mechanical pulp |
| CN109930417A (en) * | 2017-12-15 | 2019-06-25 | 中国制浆造纸研究院有限公司 | A kind of recoverying and utilizing method of cold alkali density waste liquid |
| CN110761104A (en) * | 2019-10-08 | 2020-02-07 | 中国宣纸股份有限公司 | Chlorine-free bleaching method for Chinese art paper sandalwood pulp |
| CN115491916A (en) * | 2022-09-22 | 2022-12-20 | 牡丹江恒丰纸业股份有限公司 | Conveying system and conveying method for high-concentration slurry unpowered equipment |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1154729A (en) * | 1994-07-11 | 1997-07-16 | 贝洛特工艺技术公司 | Method for bleaching wood pulp using hydrogen peroxide |
| CN1176673A (en) * | 1994-07-11 | 1998-03-18 | 具洛特工艺技术公司 | Peroxide bleaching process for cellulosic and lignocellulosic material |
| CN1050642C (en) * | 1996-06-25 | 2000-03-22 | 华南理工大学 | Everyday production 30-150 ton high concentration paper pulp bleaching method by using hydrogen peroxide |
| CN1107140C (en) * | 1998-05-14 | 2003-04-30 | 华南理工大学 | Method for bleaching medium thick paper pulp by for hydrogen peroxide for medium-small paper mill |
-
2006
- 2006-04-30 CN CNB200610035316XA patent/CN100412267C/en not_active Expired - Fee Related
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1154729A (en) * | 1994-07-11 | 1997-07-16 | 贝洛特工艺技术公司 | Method for bleaching wood pulp using hydrogen peroxide |
| CN1176673A (en) * | 1994-07-11 | 1998-03-18 | 具洛特工艺技术公司 | Peroxide bleaching process for cellulosic and lignocellulosic material |
| CN1050642C (en) * | 1996-06-25 | 2000-03-22 | 华南理工大学 | Everyday production 30-150 ton high concentration paper pulp bleaching method by using hydrogen peroxide |
| CN1107140C (en) * | 1998-05-14 | 2003-04-30 | 华南理工大学 | Method for bleaching medium thick paper pulp by for hydrogen peroxide for medium-small paper mill |
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Application publication date: 20061011 Assignee: National Engineering Research Center of papermaking and pollution control, South China University of Technology, Guangdong, China Assignor: South China University of Technology Contract record no.: 2010440000202 Denomination of invention: Method for bleaching middle and thick paper pulp by hydrogen peroxide and through double bleaching tower Granted publication date: 20080820 License type: Exclusive License Record date: 20100118 |
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