CN106638094A - P-RC APMP (pre-conditioning refiner chemical pretreatment alkaline peroxide mechanical pulp) pulping method of alkalescent hydrogen peroxide bleaching system - Google Patents
P-RC APMP (pre-conditioning refiner chemical pretreatment alkaline peroxide mechanical pulp) pulping method of alkalescent hydrogen peroxide bleaching system Download PDFInfo
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- CN106638094A CN106638094A CN201611095218.5A CN201611095218A CN106638094A CN 106638094 A CN106638094 A CN 106638094A CN 201611095218 A CN201611095218 A CN 201611095218A CN 106638094 A CN106638094 A CN 106638094A
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- paper pulp
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- bleaching
- apmp
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Classifications
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- 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
- D21C1/00—Pretreatment of the finely-divided materials before digesting
- D21C1/02—Pretreatment of the finely-divided materials before digesting with water or steam
-
- 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
- D21D1/00—Methods of beating or refining; Beaters of the Hollander type
- D21D1/20—Methods of refining
Abstract
The invention relates to a P-RC APMP (pre-conditioning refiner chemical pretreatment alkaline peroxide mechanical pulp) pulping method of an alkalescent hydrogen peroxide bleaching system, and provides a P-RC APMP pulping method using magnesium oxide and hydrogen peroxide as main bleaching agents. The magnesium oxide is used for totally replacing caustic soda in the machine pulp oxydol bleaching; sodium silicate and magnesium sulfate in a conventional method are totally replaced; the bleaching agent is added in a proper position (pulp spraying and discharging pipe positions) of the P-RCAPMP pulping process pipeline so as to provide stable pH value environment; finally, the high-yield paper pulp fiber with excellent performance is prepared.
Description
Technical field
The invention belongs to pulping and paper-making field, is related to a kind of P-RC APMP slurrying sides of alkalescent hydrogen peroxide bleaching system
Method.
Background technology
Plant fiber material shortage and problem of environmental pollution always restrict China's pulp and paper industry sustainable and healthy development
Major obstacle.In recent years, high yield cooking technique was excellent with its relatively low string resource consumption and ambient pollution burden etc.
Gesture gradually receives publicity, and develops very fast.Wherein, gentle pretreatment plus the chemically treated APMP of mill
(Pre-conditioning Refiner Chemical pretreatment Alkaline Peroxide Mechanical
Pulp, P-RCAPMP) pulp brightness is higher, mechanical strength is preferable, substitutes bleaching leaf wood chemistry in high-grade paper kind in recent years
The application aspect of slurry is becoming increasingly popular.But, traditional P-RC APMP pulping process is all with NaOH as alkalescence Jie
Matter.The strong basicity of NaOH can cause that paper pulp yield is low, waste water BOD and CODCrLoad weight, anionic trash interference etc. are a variety of
Problem, has a strong impact on production operation and the pulp quality of P-RCAPMP pulping bleachings.Therefore, domestic and international pulping and paper-making circle in recent years
Scientific research personnel actively develop the research work of the high yield cooking bleaching technology with MgO or Mg (OH) as alkali source, and in document
Disclosed in introduce magnesium alkali substitute soda high yield cooking bleaching technology：1st, Linyong Ye et al. are published in respectively
《Carbohydrate Polymers》Magazine 2012 year the 1435-1439 page of 4 phase " Effect of partially of volume 88
substituting MgO for NaOH on bleaching of pine(Pinus massoniana)
In thermomechanical pulp ", alkaline hydrogen peroxide bleaching pine class (masson pine) TMP is substituted with MgO parts, mainly
Inquire into MgO and substitute impacts of the NaOH to size performance and wastewater characteristics.Research shows that MgO substitutes part NaOH and can reduce
Dissolution rate of the chemical composition in paper pulp fiber, improves paper pulp yield, reduces drainage load.2nd, Zhao Jiangpeng et al. exists《In
State's papermaking》Magazine 2011 year the 7th the 1-6 page of the phase of volume 30《Magnesium alkali replaces the highly concentrated stop segment process of poplar P-RC APMP of soda
Parameter optimization》P-RC APMP slurrying is carried out by raw material of Triploid of Populus Tomentosa, (NaOH is used to inquire into highly concentrated stay segment technological parameter
Amount, H2O2Consumption and reaction time) impact to paper performance, find as MgO replaces the increase (0～60%) of NaOH ratios.
Tensile strength, tearability decline, and whiteness, opacity, light scattering coefficient, bulk increase.3rd, application number
The application for a patent for invention of 201210029139.X discloses a kind of leaf wood P-RCAPMP pulping process of use magnesium alkali, the method
With magnesia as alkali source, the magnesium oxide powder that purity is more than 85% is configured into slimy magnesia magma, is made
For the new alkali source of high yield pulp bleaching, part substitutes NaOH and adds in leaf wood P-RCAPMP production lines, suitable to provide
PH environment, finally prepare the high-yield pulp fiber of function admirable.
The laboratory and correlation theory research (text of existing document or the High Yield Pulping Technology for being limited to substitute magnesium alkali soda
Offer 1,2)；Or substitute the related of soda only for the magnesium alkali carried out in North America TMP to BCTMP high yield cooking techniques prevailing
Research work (document 1), does not carry out correlative study for China's P-RC APMP techniques prevailing；Also useful magnesium alkali substitutes sodium
The introduction (document 3) of the P-RC APMP production technologies of alkali, but sodium metasilicate has wherein still been used, the presence of silicon can cause slurrying to give up
The problems such as rising of liquid viscosity, particularly equipment serious scale, affect pulping system runnability.
The content of the invention
It is an object of the invention to overcome the deficiencies in the prior art part, there is provided one kind is based on magnesia, hydrogen peroxide
The P-RCAPMP pulping process of drift agent, with the caustic soda in magnesia replacing whole reducing rules hydrogen peroxide bleaching in this method, and entirely
Portion substitutes sodium metasilicate, the magnesium sulfate in conventional method, sets up New-type weak alkali hydrogen peroxide bleaching system, and this make use of magnesia micro-
Characteristic that is molten and being converted into magnesium hydroxide, replaces sodium metasilicate to play cushioning liquid effect, keeps bleaching process pH stable；Use oxygen
Change magnesium and replace sodium metasilicate, it is to avoid the bleaching waste liquor viscosity that silicon causes rises and equipment scaling problem, while fundamentally avoid
Currently employed heat pump or evaporating concentrating method process the silicon obstacle problem during reducing rules waste liquid.Above-mentioned bleaching agent is existed
The appropriate location (at spray discharge pipe) of P-RCAPMP pulping process pipelines adds, final to prepare to provide stable pH environment
Go out the high-yield pulp fiber of function admirable.
The step of a kind of P-RCAPMP pulping process of alkalescent hydrogen peroxide bleaching system, method is：
(1) commodity chip raw material, into helical tear away, is being extruded Jing after screening, washing, steam preheating softening etc. are processed
Shredder exit adds the chemicals 1 that is pre-mixed, and into Presoaker, through the wood chip that compresses, part is extensive in decompression process
Restore shape and absorb chemicals；
(2) stayed for some time in reaction warehouse by the wood chip of pre-preg, into first paragraph high-density paste mill machinery is completed
Defibrination；The fibre material for going out first paragraph fiberizer enters spray discharge pipe, while chemicals 2 is added, through the vapour of cyclone separator
Gu after separating the slurry concentration adjustment with cooling spiral, into highly concentrated reserving tower, complete the bleaching of paper pulp；
(3) paper pulp of bleaching, into low dense defibrination process operation, obtains qualified paper pulp fiber after washing.
" chemicals 1 " and " chemicals 2 " composition and its percentage by weight consumption in terms of paper pulp bone dry fiber are distinguished
It is as follows：
The magnesia is configured to suspension and uses, and concentration is 5%-8%, and the magnesia magma is separately provided conveying
Pump and feed-line.
And, the parameter setting scope of the operating unit of the pulping process is as follows：
It is pre- to steam storehouse；Temperature range is 60-100 DEG C；Minute time of staying 10-30
Reaction warehouse：Temperature range is 50-70 DEG C；Minute time of staying 10-50
Extruding ＆ Tearing Machine：Compression ratio is more than or equal to 4: 1
One section of mill：Refining concentration is 20%-40%；Refining pressure is 0.05-0.5MPa
Highly concentrated reserving tower：Temperature is 65-100 DEG C；Pulp density 20%-40%；Minute in reaction time 60-100
Eliminating potential pool：Paper pulp fiber concentration is 0.5%-10%；Temperature is 60-100 DEG C
Two sections of mills：Refining concentration is 1%-10%, atmospheric refining runs
Pressurized screen：Enter to starch concentration for 1%-10%
Pulp storage tower：Paper pulp fiber concentration is 10-20%.
And, high-yield pulp performance indications scope is as follows by obtained in described pulping process：
Paper pulp yield：85%-90% is to OD wood chip amount；
Tiny constituent content in paper pulp：10%-40% is to absolute dried paper pulp amount；
Pulp freeness：100-500ml CSF；
Paper pulp ISO whiteness：65-80%ISO；
Paper pulp bulk：2.5-3.5cm3/g；
Paper pulp fracture length：1.5-3km；
Paper pulp tear index：1-3mN.m2/g；
Ton slurry COD generating capacity ＜ 200kg；
Draining 15m is starched in ton3Under the conditions of, waste liquid viscosity declines 20%- compared with traditional soda processes hydrogen peroxide bleaching process
30%.
The present invention achieves advantages below and good effect relative to prior art：
1) New-type weak alkali hydrogen peroxide bleaching system is set up, it is adaptable to all hydrogen peroxide bleachings, including chemical pulp is completely without chlorine
Hydrogen peroxide bleaching section；
2) beneficial to magnesia slightly soluble and the characteristic of magnesium hydroxide is converted into, substitutes NaOH, can also replace sodium metasilicate to rise
To cushioning liquid effect, bleaching process pH stable is kept；
3) replace sodium metasilicate, there are problems that caused pulping waste liquor viscosity rises so as to avoid silicon, be particularly conducive to solve
Currently employed heat pump or evaporating concentrating method process the silicon obstacle problem during reducing rules waste liquid.
Specific embodiment
With reference to specific embodiment, the invention will be further described, and following examples are descriptive, is not limit
Qualitatively, it is impossible to which protection scope of the present invention is limited with this.
Embodiment 1
A kind of alkalescent hydrogen peroxide bleaching system pulping process, selected pulping raw material, chemicals and slurrying production
Equipment and specific pulping process parameter are described as follows respectively：
First, slurrying raw material and equipment
Slurrying scale up test adopts commodity poplar piece, the poplar Jing wood chipping equipments given birth to by 3-5 to be whittled into.
Magnesium alkali adopts magnesium oxide powder, and its physicochemical characteristic is：White powder, it is odorless, tasteless, nontoxic, it is highly active light
Powder is burnt, water is slightly soluble in, the suspension of its water is in alkalescent；It is insoluble in organic solvent；Acid and ammonium salt can be dissolved in；The purity of commodity is
More than 85%, calcium oxide content is not more than 2%, and impurity metal ion content is few, and (ferric ion content is not more than 0.2%；Two
Valency content of copper ion is not more than 1ppm；Manganese ion content is not more than 200ppm).Magnesium alkali needs to be configured in the medium of water in advance
Suspension, the suspension must be separately provided delivery pump and feed-line, " the spray discharge pipe " in P-RCAPMP technological processes
Place is separately added in pulping system, and consumption is 2% (in terms of bone dry fiber).The compound method of magnesium alkali suspension is as follows：
First, to volume to be passed through 2000kg clear water in the dissolving tank of 3L, (agitator is double-deck leaf to open agitator in tank
Piece, mixing speed is 60-100rpm), about 108kg magnesia pressed powders are continuously added into dissolving tank, continue to stir after adding
Mix 10 minutes, be then turned on tank outer circulation pump, make the magnesia magma that concentration is about 5.4%.
" chemicals 1 " and " chemicals 2 " and according to P-RCAPMP pulping process flows add, comprising chemicals use
Amount is as follows：
Above-mentioned percentage is that, with the percentages of the bone dry fiber weight in paper pulp, the bone dry fiber in paper pulp is to calculate
Benchmark.
2nd, the idiographic flow of pulping process
(1) poplar piece in chip bin is scrubbed, after dehydration, be transferred to pre- steaming storehouse, is passed through steam；Then, the pre- vapour of Jing
Steam the wood chip for processing and enter Extruding ＆ Tearing Machine (MSD), in MSD exits chemicals 1 is added, into Presoaker, wood chip undergoes machine
Tool extruding, dipping absorb chemicals；
(2) stayed for some time in reaction warehouse by the wood chip of pre-preg, into first paragraph high-density paste mill machinery is completed
Defibrination；The fibre material for going out first paragraph fiberizer enters spray discharge pipe, while chemicals 2 is added, through the vapour of cyclone separator
Gu after separating the slurry concentration adjustment with cooling spiral, jointly into highly concentrated reserving tower, complete with a temperature of in the regular hour
The bleaching of paper pulp, improves the optical property of paper pulp fiber；
(3) abeyance of the curling kink of paper pulp fiber is eliminated using the dehydration concentration of pressafiner and by eliminating potential pool,
Into the low dense defibrination of second segment, further machinery grinding is carried out to paper pulp fiber and is processed, develop pulp strength；
(4) paper pulp fiber is concentrated by the screening of pressurized screen, the dehydration of many disk thickeners, and dense pump is delivered to storage slurry in Jing
Tower, it is standby.
3rd, specific pulping process parameter
The technological parameter of primary operational unit is as follows：
It is pre- to steam storehouse：Temperature range is 80 DEG C；15 minutes time of staying；
Reaction warehouse：Temperature range is 60 DEG C；15 minutes time of staying；
One section of mill：Refining concentration is 35%；Refining pressure is about 0.17MPa；
Highly concentrated reserving tower：Temperature is 85 DEG C；Pulp density 30%；The liquid level (about 73% or so) in reserving tower is adjusted,
To ensure bleaching time as 90 minutes；
Eliminating potential pool：Paper pulp fiber concentration is 5%；Temperature is about 80 DEG C；
Two sections of mills：Refining concentration is about 5%, atmospheric refining runs；
Pressurized screen：Enter to starch concentration and be about 5%；
Pulp storage tower：Paper pulp fiber concentration is about 20%；
The high-yield pulp numbering produced by embodiment is 1#.
Comparative example 1
Selected pulping raw material, chemicals and slurrying production equipment are identical with the embodiment of the present application：
First, slurrying raw material and equipment
Slurrying scale up test adopts commodity poplar piece, the poplar Jing wood chipping equipments given birth to by 3-5 to be whittled into.
The amount of " chemicals 1 " and " chemicals 2 " addition is as follows：
2nd, the idiographic flow of pulping process
Using concrete technology flow process and technological parameter it is all identical with the embodiment of the present invention 1.
The high-yield pulp numbering produced by comparative example 1 is 2#.
1# and 2# high-yield pulps performance comparison such as following table：
Table 1
Remarks：The reference unit price of commodity sodium hydrate solid is 1880 yuan/ton；The reference unit price of commodity magnesia is 700
Yuan/ton；The reference unit price of technical grade sulfuric acid magnesium is 1200 yuan/ton.
As can be seen from Table 1,
When being produced with tradition bleaching reducing rules using magnesia replacing whole application, into slurry intensity and whiteness index
In the case of being basically unchanged, pulping waste liquor COD declines about 20%, and viscosity reduces about 25%, and ton slurry cost declines 110 yuan of left sides
It is right.
Claims (3)
1. the P-RC APMP pulping process of a kind of alkalescent hydrogen peroxide bleaching system, step is：
(1) by commodity wood chip is scrubbed, after dehydration, be transferred to pre- steaming storehouse, it is passed through steam, the wood chip that Jing presteamings are processed is entered
Extruding ＆ Tearing Machine, the chemicals 1 being pre-mixed is added in Extruding ＆ Tearing Machine exit, and into Presoaker, wood chip undergoes machinery and squeezes
Pressure, dipping absorb chemicals；
(2) stayed for some time in reaction warehouse by the wood chip of pre-preg, into first paragraph high-density paste mill mechanical jordaning is completed；
The fibre material for going out first paragraph fiberizer enters spray discharge pipe, while adding chemicals 2, separates admittedly through the vapour of cyclone separator
After the slurry concentration adjustment of cooling spiral, jointly into highly concentrated reserving tower, the bleaching of paper pulp is completed；
(3) abeyance of the curling kink of paper pulp fiber is eliminated using the dehydration concentration of pressafiner and by eliminating potential pool, is entered
The low dense defibrination of second segment, further machinery grinding is carried out to paper pulp fiber and is processed, and obtains paper pulp fiber；
(4) paper pulp fiber is concentrated by the screening of pressurized screen, the dehydration of many disk thickeners, and dense pump is delivered to pulp storage tower in Jing,
Obtain final slurry；Characterized in that, " chemicals 1 " and " chemicals 2 " composition and its in terms of paper pulp bone dry fiber
Percentage by weight consumption is as follows respectively：
2. method according to claim 1, it is characterised in that the magnesia is configured to suspension and uses, and concentration is
5%-8%, the magnesia magma is separately provided delivery pump and feed-line.
3. method according to claim 1, it is characterised in that：The parameter setting scope of the operating unit of the pulping process
It is as follows：
It is pre- to steam storehouse：Temperature range is 60-100 DEG C；Minute time of staying 10-30；
Reaction warehouse：Temperature range is 50-70 DEG C；Minute time of staying 10-50；
Extruding ＆ Tearing Machine：Compression ratio is more than or equal to 4: 1；
One section of mill：Refining concentration is 20%-40%；Refining pressure is 0.05-0.5MPa；
Highly concentrated reserving tower：Temperature is 65-100 DEG C；Pulp density 20%-40%, minute in reaction time 60-100；
Eliminating potential pool：Paper pulp fiber concentration is 0.5%-10%；Temperature is 60-100 DEG C；
Two sections of mills：Refining concentration is 1%-10%, atmospheric refining runs；
Pressurized screen：Enter to starch concentration for 1%-10%；
Pulp storage tower：Paper pulp fiber concentration is 10-20%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201611095218.5A CN106638094A (en) | 2016-12-02 | 2016-12-02 | P-RC APMP (pre-conditioning refiner chemical pretreatment alkaline peroxide mechanical pulp) pulping method of alkalescent hydrogen peroxide bleaching system |
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|---|---|---|---|
| CN201611095218.5A CN106638094A (en) | 2016-12-02 | 2016-12-02 | P-RC APMP (pre-conditioning refiner chemical pretreatment alkaline peroxide mechanical pulp) pulping method of alkalescent hydrogen peroxide bleaching system |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110468611A (en) * | 2019-08-14 | 2019-11-19 | 岳阳林纸股份有限公司 | A kind of PRC-APMP pulping process of Eucalyptus urophylla |
| CN110725148A (en) * | 2019-10-18 | 2020-01-24 | 天津科技大学 | Technology for stabilizing pH value in hydrogen peroxide oxidation bleaching process |
| CN112176750A (en) * | 2020-10-09 | 2021-01-05 | 岳阳林纸股份有限公司 | P-RC APMP pulping method for hardwood mixed wood |
-
2016
- 2016-12-02 CN CN201611095218.5A patent/CN106638094A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110468611A (en) * | 2019-08-14 | 2019-11-19 | 岳阳林纸股份有限公司 | A kind of PRC-APMP pulping process of Eucalyptus urophylla |
| CN110725148A (en) * | 2019-10-18 | 2020-01-24 | 天津科技大学 | Technology for stabilizing pH value in hydrogen peroxide oxidation bleaching process |
| CN112176750A (en) * | 2020-10-09 | 2021-01-05 | 岳阳林纸股份有限公司 | P-RC APMP pulping method for hardwood mixed wood |
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Application publication date: 20170510 |