CN101215794A - Zero residual base normal-pressure or low-pressure boiling high-concentration pulp preparing method by using base process - Google Patents
Zero residual base normal-pressure or low-pressure boiling high-concentration pulp preparing method by using base process Download PDFInfo
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- CN101215794A CN101215794A CNA2008100304590A CN200810030459A CN101215794A CN 101215794 A CN101215794 A CN 101215794A CN A2008100304590 A CNA2008100304590 A CN A2008100304590A CN 200810030459 A CN200810030459 A CN 200810030459A CN 101215794 A CN101215794 A CN 101215794A
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Abstract
The invention relates to a method for boiling high concentration pulping in normal pressure or low pressure by an alkaline method with zero residual alkaline, and the method comprises adding accelerating agent in the boiling process and utilizing a double screw to rub and squeeze a pulper, leading pulp making and boiling process with an alkaline method to go on in normal pressure or low pressure, and leaving no residual alkaline in black liquor, leading pulp to always keep a higher density in the pulping process of boiling, washing and bleaching, and the pulp which is prepared can meets the requirement of paper making. Accelerating agent chooses one or a plurality of magnesium hydrate, potassium hydrate, sodium metasilicate, sodium sulfide, sodium sulfite, ammonium sulfite and carbamide. Special-purpose pulping boiling equipment and high-pressure boilers are not needed by pulping paper mills through utilizing the invention, in the process of pulping, pulp always keeps higher density, and black liquid has high density, little numbers and low energy consumption, alkaline recovery project with great investment is not needed to be built, and the invention enables black liquid to prepare fertilizer or other chemical products with high quality, and the invention is suitable for popularizing and applying.
Description
Technical field
The invention belongs to the pulping technology for paper-making field, being specifically related to a kind of making does not have residual alkali in the black liquor of pulp making, carry out the slurrying new technology of higher concentration under normal pressure or the low pressure condition.
Background technology
Have a large amount of fibers and non-fibrous raw material and most of alkaline substance dissolves to become black liquor after the soda pulping process in cooking liquor, it is the pollution sources of paper industry maximum, and pollutional load can reach 90% of gross contamination load.Domestic and international large-scale papermaking enterprise is many at present administers black liquor with traditional alkali recovery technology, this technology is more effective to the environmental pollution that alleviates paper industry and cause, but traditional alkali recovery technology one-time investment is huge, build up a cover soda recovery unit and generally need invest tens million of units, and day-to-day operation appropriate litigation fees height, unable the bearing of the numerous middle-size and small-size pulping and paper-making factories of China thus, can only be with directly discharging or discharging after diluting of black liquor, cause the severe contamination of water body, because of a black liquor treatment difficult problem has caused China a large amount of middle-size and small-size slurrying enterprise to be forced to one after another close.
In addition, traditional alkali recovery technology has not only been burnt organic matter valuable in the black liquor, produces a large amount of pernicious gases simultaneously and causes secondary pollution, therefore, the further research of black liquor treatment has been become paper-making industry industry problem anxious to be solved.
Summary of the invention
The objective of the invention is to the problem huge at existing alkali recovery technology investment, that operating cost is high, a kind of alkaline cooking slurrying new technology is provided, carry out the slurrying of higher concentration under normal pressure or the low pressure condition, making does not have residual alkali in the black liquor of pulp making, is convenient to black liquor and handles.
The objective of the invention is to be achieved through the following technical solutions:
1) pretreatment of raw material: the pulping raw material of fragmentation and process dedusting, at first fully mix with alkali lye;
2) material cooking: in the pulping raw material that mixes with alkali lye, add catalyst, after stirring raw material is joined in the cook vat, logical then steam carries out normal pressure or low-pressure boiling;
Wherein catalyst is selected from one or more in magnesium hydroxide, potassium hydroxide, sodium metasilicate, sodium sulfite, ammonium sulfite, urea, the anthraquinone;
3) pulping with high density: logical steam carries out the raw material behind the atmospheric cooking, carries out high dense washing and bleaching slurrying with twin-screw rubbing extruding pulper.
Described 1) in the step, alkali liquid temperature is controlled at 10～90 ℃, and the alkali lye mass concentration is preferably 4～9%.
Wherein catalyst is 2～5% to oven dry stock quality consumption preferably.
Alkali is to oven dry stock quality consumption 4～8%.In the preferred NaOH of described alkali, potassium hydroxide, the calcium hydroxide one or more.
When steam carried out boiling, the boiling preferred pressure was 0.0～0.3Mpa, and the preferred time of boiling is 5～20 hours.
Slurrying new technology of the present invention can be a raw material with non-wood fibers such as reed, straw, bamboo chip, cotton stalk, cotton linter, fiber crops and wheat straw and timber such as poplar, birch, be to carry out pulping by cooking under zero the condition at the residual alkali of pulping, according to raw material and the slurry purposes different, slurry yield can reach 60～85%.The residual alkali of the resulting slurry of the present invention is the raw material that zero black liquor can be used as organic fertilizer or other chemical products.
With the reed is pulping raw material, and in the preprocessing process, alkali liquid temperature is a normal temperature to 80 ℃, and concentration is 5%; Catalyst A quality consumption is 3% in the slurrying processing procedure, wherein anthraquinone 0.1%, sulfurous acid ammonia 2.8%, magnesium hydroxide 0.1%, and cooking pressure is 0.0～0.2Mpa, digestion time is 5～10 hours.
With the cotton stalk is pulping raw material, and in the preprocessing process, alkali liquid temperature is a normal temperature to 80 ℃, and concentration is 4%; Catalyst A quality consumption is 3.0% in the slurrying processing procedure, wherein anthraquinone 0.1%, sodium sulfite 2.1%, potassium hydroxide 0.5%, urea 0.3%, and cooking pressure is 0.0～0.3Mpa, digestion time is 8～15 hours.
With the bamboo chip is pulping raw material, and in the preprocessing process, alkali liquid temperature is a normal temperature to 80 ℃, and concentration is 6%; Catalyst A quality consumption is 4.0% in the slurrying processing procedure, wherein anthraquinone 0.1%, sodium sulfite 2.4%, ammonium sulfite 1.5%, and cooking pressure is 0.0～0.3Mpa, digestion time is 10～20 hours.
With the bluish dogbane is pulping raw material, in the pre-preg process, add temperature and be normal temperature to 80 ℃, concentration of lye is 4mg/L, catalyst A quality consumption is 3.0% in the slurrying processing procedure, wherein sulfurous acid ammonia 2.5% and magnesium hydroxide 0.5%, cooking pressure is 0.0～0.2Mpa, digestion time is 6～12 hours.
Technical scheme of the present invention can produce following technique effect:
1, the catalyst that adopted of slurrying new technology of the present invention can impel alkali lye and lignin fast reaction, efficient degradation, and making does not have residual alkali in the black liquor of pulp making.
2, the present invention can make pulping and paper-making factory need not the huge alkali recycling engineering of construction investment expense, has effectively saved investment and producing cost.
3, the present invention can carry out boiling under normal pressure or low pressure condition, does not need special digesting apparatus and high-pressure boiler in the digestion process, has significantly reduced investment cost;
4, to wash the material concentration of washing and bleaching generally be to be lower than 20% to original technology, beats by pump to be beneficial to raw material and to carry.And raw material of the present invention is washed and is washed and bleach concentration and can be controlled in 20～45%, carries by the double helix in the twin-screw rubbing extruding pulper, and in the process of carrying, realizes defibrination, washs and wash and bleach.
5, of the present invention washing washed and the bleaching efficiency height, and the black liquor and the sewage quantity that are produced are few, and energy consumption is low.
5, use slurrying new technology of the present invention, pulp yield can reach 60～90%, finished product pulp yield height, and can satisfy the needs of papermaking;
6, the present invention makes black liquor of pulp making be used for the preparation quality excellent organic fertilizer becomes possibility.
Advantage of the present invention also is: atmospheric cooking is preferably adopted in slurrying of the present invention, and the waste hot steam of traditional digestion process can be back to pulping by cooking, improves steam utilization.
In sum, the present invention makes pulping and paper-making factory need not special-purpose pulping and digesting equipment and high-pressure boiler, in the pulping process, slurry remains higher concentration, the black liquid consistency height, and quantity is few, energy consumption is low, need not the huge alkali recycling engineering of construction investment, and make black liquor be used for the good fertilizer of preparation quality or other chemical products become possibility, be suitable for promoting the use of.
The specific embodiment
Following examples are intended to illustrate that the present invention rather than the present invention further limit, and embodiments of the present invention can be implemented in the described any mode of summary of the invention.
Embodiment 1:
In and the reed that dedusting is good broken at 2000kg, the adding temperature is 80 ℃, and concentration is 5% aqueous slkali 700L, under agitation adds catalyst, joins after stirring to carry out boiling in the digester.Cooking pressure is that 0.0～0.3Mpa, digestion time are that 6 hours, slurry concentration are controlled to be 20～45%, pulping pH value is 6.5～7.5, black liquor pH value is 6.5～7.5, the catalyst quality consumption is 3%, wherein: sodium sulfite 2.6%, magnesium hydroxide and sodium metasilicate each 0.2%.Raw material is washed and is washed and slurrying with twin-screw rubbing extruding pulper (the positive twin-screw pulping equipment in sky, Hebei Co., Ltd buys) after the boiling, dense at slurry with double disc refiner then is to finish grind under 6% condition, the pulping beating degree is 38 degree, join with homemade secondary stock and to copy high-strength corrugated base paper, the reed pulp additional proportion is 20% (mass ratio), becomes the every quality index of paper all to reach the standard of GB13023-91A level fluting medium.
Embodiment 2:
In and the cotton stalk that dedusting is good broken at 2000kg, the adding temperature is 70 ℃, and concentration is 4% aqueous slkali 700L, under agitation adds catalyst, joins after stirring to carry out boiling in the digester.Cooking pressure be 0.0～0.2Mpa, digestion time be 10 hours, the slurry concentration be controlled to be 20～45%, pulping pH value is 6.5～7.5, black liquor pH value is 6.5～7.5, the catalyst quality consumption is 4%, wherein anthraquinone 0.1%, sodium sulfite 3.5%, potassium hydroxide 0.3% and urea 0.1%.Raw material is washed with twin-screw extruding pulper and is washed and slurrying after the boiling, dense at slurry with double disc refiner then is to finish grind under 6% condition, the pulping beating degree is 35 degree, join with homemade secondary stock and to copy high-strength corrugated base paper, the cotton stalk pulp additional proportion is 30%, becomes the every quality index of paper all to reach the standard of GB13023-91A level fluting medium.
Embodiment 3:
In and the bamboo chip that dedusting is good broken at 2000kg, the adding temperature is 80 ℃, and concentration is 6% aqueous slkali 700L, under agitation adds catalyst, joins after stirring to carry out boiling in the digester.Cooking pressure is that 0.0～0.2Mpa, digestion time are that 15 hours, slurry concentration are 20～45%, pulping pH value is 6.5～7.5, black liquor pH value is 6.5～7.5, the catalyst quality consumption is 3%, wherein: anthraquinone 0.15%, sodium sulfite 2.7% and magnesium hydroxide 0.15%.Raw material is washed with twin-screw rubbing extruding pulper and is washed and slurrying after the boiling, dense at slurry with double disc refiner then is to finish grind under 6% condition, the pulping beating degree is 42 degree, and the brown paper of the 80g that manufactures paper with pulp after the making beating becomes the every quality index of paper all to reach the requirement of QB/T3516-1999 standard A level paper.
Embodiment 4:
In and the bluish dogbane that dedusting is good broken at 2000kg, the adding temperature is 80 ℃, and concentration is 4% aqueous slkali 700L, under agitation adds catalyst, joins after stirring to carry out boiling in the digester.Cooking pressure is that 0.0～0.2Mpa, digestion time are that 10 hours, slurry concentration are 20～45%, pulping pH value is 6.5～7.5, and black liquor pH value is 6.5～7.5, and the catalyst quality consumption is 3%, wherein: sodium sulfite 2.5% and magnesium hydroxide 0.5%.Raw material is washed with twin-screw rubbing extruding pulper and is washed and slurrying after the boiling, dense at slurry with double disc refiner then is to finish grind under 6% condition, the pulping beating degree is 40 degree, join with homemade secondary stock and to copy high-strength corrugated base paper, bluish dogbane slurry additional proportion is 30%, manufacture paper with pulp after the making beating fluting medium of 150g becomes the every quality index of paper all to reach the standard of GB13023-91A level fluting medium.
Pulping technique of the present invention can be a raw material with timber such as non-wood fibers such as reed, bagasse, straw, bamboo chip, cotton stalk, cotton linter, fiber crops and wheat straw and eucalyptus, poplar, birch, be to carry out pulping by cooking under zero the condition at the residual alkali of pulping, according to raw material and the slurry purposes different, slurry yield can reach 60～85%.
Claims (10)
1. alkaline process zero a residual alkali normal pressure or a low-pressure boiling high-concentration pulping process is characterized in that, may further comprise the steps:
1) pretreatment of raw material: the pulping raw material of fragmentation and process dedusting, at first mix with alkali lye;
2) material cooking: in the pulping raw material that mixes with alkali lye, add catalyst, after stirring raw material is joined in the cook vat, logical then steam carries out normal pressure or low-pressure boiling;
Wherein catalyst is selected from one or more in magnesium hydroxide, potassium hydroxide, sodium metasilicate, sodium sulfite, ammonium sulfite, urea, the anthraquinone.
3) pulping with high density: logical steam carries out the raw material behind the atmospheric cooking, carries out high dense washing and bleaching slurrying with twin-screw rubbing extruding pulper.
2. a kind of alkaline process according to claim 1 zero residual alkali normal pressure or low-pressure boiling high-concentration pulping process is characterized in that wherein catalyst is 2～5% to the quality consumption of oven dry stock.
3. a kind of alkaline process according to claim 1 zero residual alkali normal pressure or low-pressure boiling high-concentration pulping process is characterized in that described normal pressure or low-pressure boiling pressure are 0.0～0.3Mpa.
4. a kind of alkaline process according to claim 1 zero residual alkali normal pressure or low-pressure boiling high-concentration pulping process is characterized in that digestion time is 5～20 hours.；
5. according to each described a kind of alkaline process of claim 1-4 zero residual alkali normal pressure or low-pressure boiling high-concentration pulping process, it is characterized in that, raw material in boiling, wash wash with bleaching process in, mass concentration is 20～45%.
6. a kind of alkaline process according to claim 1 zero residual alkali normal pressure or low-pressure boiling high-concentration pulping process is characterized in that 1) alkali liquid temperature is controlled at 10 ℃ to 90 ℃ in the step, and the alkali lye mass concentration is 4～9%.
7. according to claim 1 or 6 described a kind of alkaline process, zero residual alkali normal pressure or low-pressure boiling high-concentration pulping process, it is characterized in that alkali is to oven dry stock quality consumption 4～8%.
8. a kind of alkaline process according to claim 1 zero residual alkali normal pressure or low-pressure boiling high-concentration pulping process is characterized in that:
With the reed is pulping raw material, and in the preprocessing process, alkali liquid temperature is a normal temperature to 90 ℃, and mass concentration is 4～5%; The catalyst quality consumption is 3% in the digestion process, wherein anthraquinone 0.1%, sulfurous acid ammonia 2.8%, magnesium hydroxide 0.1%, and cooking pressure is 0.0～0.2Mpa, digestion time is 5～10 hours.
9. a kind of alkaline process according to claim 1 zero residual alkali normal pressure or low-pressure boiling high-concentration pulping process is characterized in that:
With the cotton stalk is pulping raw material, and in the preprocessing process, alkali liquid temperature is a normal temperature to 90 ℃, and mass concentration is 4%; Catalyst A quality consumption is 3.0% in the slurrying processing procedure, wherein sodium sulfite 2.3%, potassium hydroxide 0.5%, urea 0.2%, and cooking pressure is 0.0～0.2Mpa, digestion time is 8～15 hours.
10. a kind of alkaline process according to claim 1 zero residual alkali normal pressure or low-pressure boiling high-concentration pulping process is characterized in that:
With the bamboo chip is pulping raw material, and in the preprocessing process, alkali liquid temperature is a normal temperature to 90 ℃, and mass concentration is 6%; Catalyst A quality consumption is 3.5% in the slurrying processing procedure, wherein anthraquinone 0.1%, sulfurous acid ammonia 2.6%, sodium metasilicate 0.3%, and potassium hydroxide 0.5%, cooking pressure are 0.0～0.2Mpa, digestion time is 10～20 hours.
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| CNA2008100304590A CN101215794A (en) | 2008-01-11 | 2008-01-11 | Zero residual base normal-pressure or low-pressure boiling high-concentration pulp preparing method by using base process |
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| CNA2008100304590A CN101215794A (en) | 2008-01-11 | 2008-01-11 | Zero residual base normal-pressure or low-pressure boiling high-concentration pulp preparing method by using base process |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010069151A1 (en) * | 2008-12-19 | 2010-06-24 | 北京英力和泓新材料技术有限公司 | Process for extracting cellulose |
| CN102212973A (en) * | 2011-04-05 | 2011-10-12 | 凌受明 | Cooking liquor and preparation method of cotton stalk bark pulp |
| CN103255660A (en) * | 2013-05-31 | 2013-08-21 | 台州学院 | Process for extracting of bamboo fibers |
| CN105178082A (en) * | 2015-09-18 | 2015-12-23 | 新疆国力源投资有限公司 | Method for preparing bamboo willow unbleached pulp |
| CN105256624A (en) * | 2015-09-18 | 2016-01-20 | 新疆国力源投资有限公司 | Method for preparing natural color bamboo pulp |
| CN105297515A (en) * | 2015-09-18 | 2016-02-03 | 新疆国力源投资有限公司 | Method for preparing unbleached pulp from sugarcane bagasse |
| CN105648815A (en) * | 2016-03-28 | 2016-06-08 | 新疆国力源环保科技有限公司 | Method for making corrugated base paper by rice straw unbleach pulp |
| CN105821699A (en) * | 2016-03-28 | 2016-08-03 | 新疆国力源环保科技有限公司 | Method for making degradable ground film paper from cotton stalks |
| CN105821690A (en) * | 2016-03-28 | 2016-08-03 | 新疆国力源环保科技有限公司 | Method for preparing unbleached pulp from rice straw |
| CN107558283A (en) * | 2017-07-24 | 2018-01-09 | 广西柳城县成霖农业科技有限公司 | A kind of resource reutilization method of bagasse |
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2008
- 2008-01-11 CN CNA2008100304590A patent/CN101215794A/en active Pending
Cited By (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2010069151A1 (en) * | 2008-12-19 | 2010-06-24 | 北京英力和泓新材料技术有限公司 | Process for extracting cellulose |
| CN102212973A (en) * | 2011-04-05 | 2011-10-12 | 凌受明 | Cooking liquor and preparation method of cotton stalk bark pulp |
| CN102212973B (en) * | 2011-04-05 | 2014-12-03 | 凌受明 | Cooking liquor and preparation method of cotton stalk bark pulp |
| CN103255660A (en) * | 2013-05-31 | 2013-08-21 | 台州学院 | Process for extracting of bamboo fibers |
| CN103255660B (en) * | 2013-05-31 | 2015-12-02 | 台州学院 | A kind of technique extracting mao bamboon fiber |
| CN105256624A (en) * | 2015-09-18 | 2016-01-20 | 新疆国力源投资有限公司 | Method for preparing natural color bamboo pulp |
| CN105178082A (en) * | 2015-09-18 | 2015-12-23 | 新疆国力源投资有限公司 | Method for preparing bamboo willow unbleached pulp |
| CN105297515A (en) * | 2015-09-18 | 2016-02-03 | 新疆国力源投资有限公司 | Method for preparing unbleached pulp from sugarcane bagasse |
| CN105297515B (en) * | 2015-09-18 | 2017-12-29 | 新疆国力源投资有限公司 | The method of bagasse natural color pulp |
| CN105648815A (en) * | 2016-03-28 | 2016-06-08 | 新疆国力源环保科技有限公司 | Method for making corrugated base paper by rice straw unbleach pulp |
| CN105821699A (en) * | 2016-03-28 | 2016-08-03 | 新疆国力源环保科技有限公司 | Method for making degradable ground film paper from cotton stalks |
| CN105821690A (en) * | 2016-03-28 | 2016-08-03 | 新疆国力源环保科技有限公司 | Method for preparing unbleached pulp from rice straw |
| WO2017166854A1 (en) * | 2016-03-28 | 2017-10-05 | 新疆国力源投资有限公司 | Method for making corrugated medium using brownstock pulp of straw |
| CN107558283A (en) * | 2017-07-24 | 2018-01-09 | 广西柳城县成霖农业科技有限公司 | A kind of resource reutilization method of bagasse |
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