CN101573491A - Process for the production of cellulosic product - Google Patents

Abstract

The present invention relates to a process for the production of a cellulosic product which comprises providing an aqueous thick suspension containing cellulosic fibers having a fiber concentration of at least about 2% by weight; adding to the thick suspension an aluminum compound, alkaline earth metal salt and acid; diluting the obtained thick suspension to form a thin suspension; adding to the thin suspension one or more drainage and retention aids; and dewatering the obtained thin suspension. The invention further relates to a process for the production of a cellulosic product which comprises providing an aqueous thick suspension containing cellulosic fibers having a fiber concentration of at least about 2% by weight and an alkaline earth metal ion concentration of at least about 100 mg/l; adding to the thick suspension an aluminum compound and optionally an acid to obtain a pH of from about 4 to about 5.5; diluting the obtained thick suspension to form a thin suspension; adding to the thin suspension one or more drainage and retention aids; and dewatering the obtained thin suspension. The invention also relates to an aqueous composition comprising a mixture of an aluminum compound, alkaline earth metal salt and acid and the use of the composition.

Description

Make the method for cellulose product

Technical field

The present invention relates to make the method for cellulose product.More specifically, the present invention relates to comprise in the water slurry of cellulose fiber, add special additive, then with the method for its dehydration with the manufacturing cellulose product that forms cellulose product.

Background technology

In field of papermaking, cellulose fiber and the filler of choosing wantonly and the water slurry of additive are sent into head box, head box is sprayed onto this suspension on the forming web.See through forming web filtrate from this suspension, thereby at this online wet web that forms, and with the further dehydration and dry in the dryer section of paper machine of this paper web.Add in this suspension traditionally and help the filter retention agent, promoting drainage, and this is online so that they are stayed with fiber to impel particulate to be adsorbed onto on the cellulose fibre.

Except cellulose fibre, the water slurry of cellulose fiber may also contain the compound that production process is had negative effect.This compounds can be present in from magma with from the suspension that reclaims paper pulp.The compound that discharges in slurrying and the bleaching operating process often is known as resin.The example of resin comprises wood gum, for example lipophilic extract (fat and resin acid, sterol, stearoyl ester, triglycerides) and fat, terpenes, terpene, wax etc.This compounds causes the high anionic charge of suspension.

In addition, especially plain boiled water by the sealing paper mill of height recirculation in, this suspension also may comprise charged contaminants, salt for example, with various Xylon polymerized things, it is charged, low charged and uncharged compound aspect the absorption of the performance chemicals (for example helping filter retention agent, sizing agent etc.) that adds and interaction with the cellulose competition.Usually, this class interfering compound is known as the anion refuse.

All above-claimed cpds disturb the autofrettage of paper pulp and paper in every way.High anionic charge for the compensate for disturbances material causes has used the cationic additive that does a large amount in paper-making process, they help to improve dehydration and keep.

United States Patent (USP) 4,388,150 disclose in using the paper process of mineral filler and have used cationic starch with collodial silica, keep and drainage with improvement, and improve the characteristic of gained paper.

EP-A 0700473 discloses by add cationic extended chain polypropylene acid amides in the water slurry of cellulose fiber and has added polyaluminium salts and alkali or the sour paper process of keeping and/or dewatering of improving then.

Although in fact significantly improved the cellulose fiber water slurry drainage and keep, but still need to improve, especially when making cellulose product derived from the cellulose water slurry of mechanical pulp.Therefore, the purpose of this invention is to provide at the drainage of autofrettage and have the method for further improved manufacturing cellulose product aspect keeping.Other purpose will manifest hereinafter.

Brief summary of the invention

The present invention relates to make the method for cellulose product, it comprises:

(i) provide the moisture dense suspension of the fibre concentration cellulose fiber, that have about at least 2 weight %;

(ii) in this dense suspension, add:

(I) aluminium compound;

(II) alkali salt;

(III) acid;

(iii) the gained dense suspension is diluted to form dilute suspension;

(iv) in this dilute suspension, add one or more and help the filter retention agent; With

(v) the gained dilute suspension is dewatered.

The invention still further relates to the method for making cellulose product, it comprises:

(i) provide the moisture dense suspension of cellulose fiber, this dense suspension has:

(a) fibre concentration of about at least 2 weight %;

(b) the alkaline-earth metal ions concentration of about at least 100 mg/litre;

(ii) in this dense suspension, add aluminium compound and randomly add sour, to obtain about 4 to about 5.5 pH value;

(iii) the gained dense suspension is diluted to form dilute suspension;

(iv) in this dilute suspension, add one or more and help the filter retention agent; With

(v) the gained dilute suspension is dewatered.

The invention further relates to a kind of Aquo-composition, it comprises following mixtures of material:

(I) aluminium compound;

(II) alkali salt; With

(III) acid;

Wherein the weight ratio of aluminium compound, alkali salt and acid is about 60: 1: 0.1 to about 5: 1: 1.

The invention further relates to the purposes of described Aquo-composition, as the additive in the method for making cellulose product.

Detailed Description Of The Invention

According to the present invention, have been found that, the paper moulding can significantly do not damaged by following method, or even improve and to improve drainage under the situation of paper moulding and keep: this method comprises aluminium compound, alkali salt and acid add the cellulose fiber, have in the water slurry (being also referred to as dense suspension in this article) of about at least 2 weight % fibre concentrations, this dense suspension is diluted to form dilute suspension (being also referred to as diluted suspension in this article), one or more help the filter retention agent with adding in this dilute suspension, and the dehydration of gained dilute suspension is formed cellulose product.

When the present invention makes cellulose product at the suspension that by all types of cellulose suspensions, particularly contains the suspension of machinery or recycle slurry and have high content of salt (high conductivity) and a colloidal materials, with in paper process, drainage is provided, has kept the improvement with yield with high whitewater closure degree (i.e. height white water loop and limited fresh water supply).Therefore, the present invention can improve the speed of paper machine and use the additive than low dosage to produce corresponding drainage and/or keep effect, produces improved paper process and economic benefit thus.

Can comprise alum, aluminate (for example sodium aluminate or potassium aluminate), aluminium chloride, aluminum nitrate and polymeric aluminum compound by aluminium compound used according to the invention, for example aluminium polychloride, polyaluminium sulfate and not only polymeric aluminum compound, the polymeric aluminum silicate-sulphate of chloride ion-containing but also sulphate-containing ion, and composition thereof.This polymeric aluminum compound can also contain other anion, for example from the anion of phosphoric acid, organic acid (for example citric acid and oxalic acid).Alum used herein not only comprises the double salt K of aluminum sulfate and potassium sulfate ₂SO ₄* Al ₂(SO ₄) ₃* 24H ₂O also comprises aluminum sulfate Al ₂(SO ₄) ₃* 14H ₂O, Al ₂(SO ₄) ₃* 8H ₂O and their mixture.The example of suitable aluminium compound comprises United States Patent (USP) 5,127, those disclosed in 994, and this patent is incorporated herein by this reference.Suitably, described aluminium compound is selected from alum, aluminium chloride, polymeric aluminum compound (for example aluminium polychloride and poly aluminium sulfate silicate) and aluminate, preferred alum.

Can comprise magnesium, calcium and barium salt by alkali salt used according to the invention.This salt can have the halogen of being selected from ion, sulfate radical, carbonate, nitrate radical or organic acid anion.Suitably, this alkali salt is selected from magnesium and calcium salt, for example magnesium chloride, magnesium sulfate, calcium chloride and barium sulfate.This alkali salt is preferably magnesium salts.In a preferred embodiment of the invention, alkali salt is added in the dense suspension, to obtain about at least 100 mg/litre, the alkaline-earth metal ions concentration of about at least 150 mg/litre and preferred at least 200 mg/litre suitably.Dense suspension can have high concentration based on Ca ²⁺And Mg ²⁺The alkali salt of ion, these salt may be derived from the cellulose fiber peacekeeping filler that is used to form this suspension, particularly in integrated factory, in integrated factory, usually will mix with water from the concentrated aqueous fibrous suspension of pulp mill, be applicable to the dilute suspension of papermaking in the paper mill with formation.This salt also may be derived from and add the various additives in the dense suspension and be derived from the fresh water of supplying to this technology.In the method for plain boiled water height recirculation, salinity is higher usually, and this may cause salt significantly to accumulate in the recirculated water of this technology.Therefore, the dense suspension of the alkaline-earth metal ions concentration with about at least 100 mg/litre can be provided under the situation of further not adding alkali salt.

Can acid used according to the invention comprise inorganic acid, for example sulfuric acid, hydrochloric acid, phosphoric acid, hydrochloric acid and nitric acid, and organic acid, for example carboxylic acid, for example oxalic acid and citric acid.This acid is preferably inorganic acid, preferred hydrochloric acid or sulfuric acid.Should acid add in the dense suspension, to obtain about 2 to about 6 scopes, for example in about 4 pH values to about 5.5 scopes.Also can be by only aluminium compound being added the pH scope that obtains appointment in the dense suspension.In the present invention further optimization embodiment, optional acid is added in this dense suspension, to obtain about 4 to about 5.5 pH value.Preferably, according to the interpolation of aluminium compound of the present invention and optional acid make the pH value of dense suspension reduce to shown in scope.For example, add aluminium compound and can have about at least pH value of 6, for example about at least 6.5 with optional this sour dense suspension.

According to the preferred embodiments of the invention, in the dense suspension of pulp-making method, add one or more of aluminium compound, alkali salt and acid.This dense suspension can be derived from several paper pulp, for example chemical pulp (as sulfate and sulfite pulp), mechanical pulp (for example heat-mechanical pulp, chemistry-Re mechanical pulp), organic solvent paper pulp (orgasolv pulp), refinery's paper pulp or from the ground wood pulp of cork and hardwood, or derived from the fiber of annual plant (for example napier grass, bagasse, flax, straw etc.) with based on the suspension of recycled fiber.In a preferred embodiment of the invention, this dense suspension contains the cellulose fibre derived from mechanical pulp, and the content of mechanical pulp is preferably at least 50 weight % of paper pulp gross weight.Can be behind chemical digesting, for example after thick slurry washer or after (chemistry-) mechanical pulp refining, add aluminium compound, alkali salt and/or sour one or more.Usually, in comprising the multistage bleaching of different bleaching stages with association with pulp bleaching.The example of suitable bleaching stage comprises dioxide bleaching stage, for example elemental chlorine and chlorine dioxide bleaching stage; Nonchlorine bleach stage, for example peroxide stage, for example ozone, hydrogen peroxide and peracetic acid; And the combining of chlorine and nonchlorine bleach and oxidation stage, randomly combine with reduction phase (as handling) with dithionite.This paper pulp can be hydrogen peroxide bleaching, and adds aluminium compound, alkali salt and acid one or more behind bleaching stage.In a preferred embodiment of the invention, in this dense suspension, add one or more of aluminium compound, alkali salt and acid in the dilution point behind the bleaching stage.In another preferred embodiment of the present invention, before this dense suspension arrives paper pulp storage tank, one or more addings of aluminium compound, alkali salt and acid are present in the dense suspension in the blender.In the present invention further optimization embodiment, behind storage tank, in the way of going to the paper mill mixing channel, one or more of aluminium compound, alkali salt and acid are added in dense suspensions.In the time will adding aluminium compound, alkali salt and acid, this dense suspension has about at least 2%, suitably about at least 3% and the fibre concentration of preferred about at least 3.5 weight %.This concentration can be up to about 10 weight %.Preferably, in the time of in the dense suspension that aluminium compound, alkali salt and acid is added pulp-making method, be used in after the gained dense suspension in the paper process in the integrated factory.

Aluminium compound, alkali salt and acid (being also referred to as component in this article) can be distinguished or add simultaneously in this dense suspension.When adding component respectively, they can add with any order.Suitably, before adding alkali salt and/or acid, add aluminium compound, and can before the acid, with acid simultaneously or after acid, add alkali salt.When adding component at the same time, they can add independently and/or with form of mixtures.The example of the appropriate mode of Tian Jiaing comprises the independent three kinds of components of adding simultaneously, add with the composition that comprises these components, and independent add component add two kinds of described component with form of mixtures in the lump.This mixture can comprise aluminium compound and alkali salt and acid one or both of.In a preferred embodiment of the invention, aluminium compound and alkali salt add simultaneously with form of mixtures, and optional adding acid in this dense suspension.

The invention further relates to Aquo-composition of the mixture that comprises said components and uses thereof.This Aquo-composition is suitable as the additive in the method for making cellulose product, preferably as helping the filter retention agent in these class methods.Preferably, said composition helps filter and/or retention agent (it preferably comprises at least a cationic polymerization retention agent and preferred the adding in the dilute suspension) to be used in combination with one or more.Preferably, said composition is moisture.This aluminium compound, alkali salt and acid can be to exist at 5 to 99 weight %, the dry matter content that changes in the wide region of 20 to 90 weight % suitably.These components can be present in the said composition with about 60: 1: 0.01 weight ratios to about 5: 1: 0.1 aluminium compound, alkali salt and acid.Composition of the present invention can preferably under agitation mix by aluminium compound, alkali salt and acid are mixed and preparation easily.

Component of the present invention can add with the amount that changes in wide boundary in this dense suspension.Usually, these components with in paper process with do not add these components and compare and produce drainage preferably, keep and/or the amount of yield is added.Aluminium compound is usually with about at least 10 kg/ton (ton is meant metric ton, and based on the dry weight of dense suspension), the amount of about at least 30 kg/ton is added usually, and the upper limit is typically about 90 kg/ton, is about 40 kg/ton suitably.Similarly, if use alkali salt, it is typically about 40 kg/ton with about at least 0.5 kg/ton, the amount interpolation of about at least 1.0 kg/ton, and the upper limit usually usually, is about 35 kg/ton suitably.Similarly, acid is typically about 2.0 kg/ton with about at least 0.01 kg/ton, the amount interpolation of about at least 0.05 kg/ton, and the upper limit usually usually, is about 1.5 kg/ton suitably.When using Aquo-composition of the present invention, it is typically about 120 kg/ton with about at least 10 kg/ton, the amount interpolation of about at least 30 kg/ton, and the upper limit usually usually, is about 50 kg/ton suitably.

After in dense suspension, adding aluminium compound, alkali salt and acid according to the present invention, with this dense suspension dilution, form the moisture dilute suspension that has less than the cellulose fiber of 2 weight % fibre concentrations, be also referred to as dilute suspension in this article.This dilute suspension has about 0.2 to about 1.5 weight % usually, about 0.5 fibre concentration to about 1.0 weight % for example.Can utilize any water, for example water, the aqueous solution and aqueous suspension, for example plain boiled water or clarification plain boiled water are realized dilution.

Add aluminium compound, alkali salt and acid according to the present invention after, if desired, can by add alkali with the pH value of moisture dense suspension or dilute suspension be increased to about 5.5 to about 10, suitably about 6 to about 9 and preferably approximately 6 to about 8 scope.The example of suitable alkali comprises alkali-metal bicarbonate and carbonate, and alkali metal hydroxide, is sodium bicarbonate, sodium carbonate and NaOH suitably, preferred NaOH.This alkali can help the filter retention agent add before, add simultaneously or afterwards.This alkali preferably added before interpolation helps the filter retention agent.

Used according to the invention one or more help the filter retention agent, preferably use in paper process.This method comprises dense suspension (its can available from pulp-making method) dilution and to add one or more and to help the filter retention agent in this dilute suspension, and gained suspension is dewatered to form dilute suspension.Term used herein " help filter retention agent " is meant one or more additives, when in the suspension that it is added the cellulose fiber, compares with not adding described one or more additives, has obtained preferably drainage and keeps.

The suitable example that helps the filter retention agent comprises cationic and anionic organic polymer, siliceous material and their mixture.Use organic polymer and siliceous material as helping the filter retention agent or being as known in the art as flocculant.At least a cation type polymer of preferred use is as helping the filter retention agent.Term used herein " cation type polymer " is meant the organic polymer with one or more cation groups.This cation type polymer can also contain anionic group, as long as this polymer has overall cationic charge.Term used herein " anionic polymer " is meant the organic polymer with one or more anionic groups.This anionic polymer also can contain cation group, as long as this polymer has overall anionic charge.

The polymer that is suitable in the method can be from natural or synthetic source, and they can be straight chain, side chain or crosslinked.The example of suitable polymers comprises cationic polysaccharide, preferred starch; CATION and anionic chain growth polymerization thing, the polymer of preferred cationic and anionic acrylamido; And cationic poly (diallyldimethylammonium chloride); Cationic polymine; Cationic polyamine; Cationic daiamid and based on the polymer of ethernamine.The polymer of cationic starch and cationic acrylamido is particularly preferred polymer, and they can be separately, use together or with other polymer (for example other is cationic and/or anionic polymer) each other.The weight average molecular weight of this polymer is higher than 1,000,000 suitably, and preferably is higher than 2,000,000.The upper limit is not crucial; It can be for about 50,000,000, and is common 30,000,000, and about suitably 25,000,000.But, may be higher from the molecular weight of the polymer of natural origin.

The example of suitable siliceous material comprises anionic silica-based particles and montmorillonite type anionic clay.This siliceous material preferably has the particle in the colloidal state particle size range.The preferred anionic silica-based particles of using is promptly based on SiO ₂Or the particle of silicic acid, and this class particle is usually with aqueous, colloidal dispersion liquid (so-called colloidal sol) form supply.The example of suitable silica-based particles comprises colloidal silica and dissimilar poly-silicic acid (homopolymerization or copolymerization), for example polymeric silicicacid, poly-silicic acid microgel, polysilicate and polysilicate microgels.This silica-based sols can be modified, and contains other element, for example aluminium, boron, nitrogen, zirconium, gallium, titanium etc., and these elements can be present in water and/or the silica-based particles.The example of this suitable class silica-based particles comprises colloidal aluminium improved silica, alumina silicate, poly-aluminosilicate and poly-aluminosilicate microgel.Also can use the mixture of the suitable silica-based particles of this class.The suitable example that helps the filter retention agent that comprises the anionic silica-based particles comprises United States Patent (USP) 4,388,150; 4,927,498; 4,954,220; 4,961,825; 4,980,025; 5,127,994; 5,176,891; 5,368,833; 5,447,604; 5,470,435; 5,543,014; 5,571,494; 5,573,674; 5,584,966; 5,603,805; 5,688,482; With 5,707, those disclosed in 493, these patents are incorporated herein by this reference.

The example of suitable anionic silica-based particles comprise particle mean size be lower than about 100 nanometers, preferably be lower than about 20 nanometers, more preferably about 1 to those of about 10 nanometers.As common in the silica chemistry, granularity is meant the particle mean size of primary particle, and these primary particles can be that assemble or non-gathering.The specific area of silica-based particles is higher than 50 meters squared per gram suitably, and preferably is higher than 100 meters squared per gram.Usually, specific surface can be up to about 1700 meters squared per gram, preferably up to 1000 meters squared per gram.By with known manner, for example as G.W.Sears at AnalyticalChemistry 28 (1956): 12, among the 1981-1983 and United States Patent (USP) 5,176, described in 891, measure specific area with the NaOH titration.Therefore given area represents the average specific surface area of particle.

In the preferred embodiment of the invention, use that the S-value is 8 to 50%, the silica-based particles of preferred 10 to 40% solation.The S-value can be as Iler﹠amp; Dalton is in J.Phys.Chem.60 (1956), measurements and calculations described in the 955-957.The S-value is meant assembles or microgel formation degree, and the higher aggregation extent of low S-value representative.

The example of suitable montmorillonite type anionic clay comprises those that have negative electrical charge from the teeth outwards, comprises imvite/bentonite, hectorite, beidellite, nontronite, saponite, LAPONITE (laponite), preferred bentonite.The bentonitic example of suitable anionic comprises United States Patent (USP) 4,753,710; 5,071,512; With 5,607, those disclosed in 552, these patents are incorporated herein by this reference.

Cationic coagulating agent be can certainly use in the method for the invention, anion refuse agent for capturing and fixative are known as again.The example of suitable cationic coagulating agent comprises water-soluble organic polymer coagulating agent.Cationic coagulating agent can use separately or together, and promptly polymeric coagulants can be used in combination with inorganic coagulant.The example of the suitable cationic coagulating agent of water-soluble organic polymer comprises the polymer of grams of monomer blend cationic polyamine, daiamid, polymine, dicyandiamide condensation polymer and water-soluble olefinic bond formula unsaturated monomer or that be made of 50 to 100 moles of % cationic monomers and 0 to 50 mole of other monomer of %.The amount of cationic monomer is generally at least 80 moles of %, is 100% suitably.The example of the suitable unsaturated cationic monomer of ethylenic comprises (methyl) propenoic acid dialkyl aminoalkyl ester and dialkyl aminoalkyl (methyl) acrylamide, be preferably the season form, with the poly (dially dialkyl) ammonium chloride, diallyldimethylammonium chloride (DADMAC) for example is preferably homopolymers and the copolymer of DADMAC.The cationic coagulating agent of this organic polymer has 1,000 to 3,000 usually, and 000, be 5,000 to 700,000 and preferred 10,000 to 500,000 weight average molecular weight suitably.

This helps the filter retention agent to add in the dilute suspension in a usual manner and with any order.When using siliceous material, preferably before adding siliceous material, cation type polymer is added in this dilute suspension, but also can use opposite interpolation order.More preferably added cation type polymer before shear stage, this can be selected from pumping, mixing, cleaning etc., and adds siliceous material after this shear stage.When using cationic coagulating agent, preferably before it is added in suspension at adding cation type polymer and siliceous material (if you are using).Perhaps, can cationic coagulating agent and cation type polymer is basic simultaneously (independently or with form of mixtures) add in this suspension, as in the United States Patent (USP) 5,858,174 that is incorporated herein by this reference disclosed like that.

Help the filter retention agent to add in the dilute suspension that will dewater with the amount that can change in wide boundary, this especially depends on the type of additive and number, the type of cellulose suspension, salt content, salt type, filer content, filler type, add point, whitewater closure degree etc.Usually, this retention and drainage aid agent adds to compare the amount that obtains drainage preferably and/or keep when not using this additive.Based on the plain suspension of dried fibres, the about at least usually 0.001 weight % of cation type polymer, the amount interpolation of about at least 0.005 weight % usually, and the upper limit is typically about 3%, about suitably 1.5 weight %.The addition commonly used of cation type polymer is about 0.01% until about 0.5 weight %.Based on the plain suspension of dried fibres, the anionic material, for example siliceous material (being anionic silica-based particles and montmorillonite type anionic clay) and anionic organic polymer about at least 0.001 weight %, the amount interpolation of about at least 0.005 weight % usually usually, and the upper limit is typically about 1.0%, about suitably 0.6 weight %.

When using cationic coagulating agent in the method, calculate by dried coagulating agent, based on the plain suspension of dried fibres, the amount that it can about at least 0.001 weight % is added.Suitably, this amount is for about 0.05 to about 3.0%, and preferably approximately 0.1 to about 2.0%.

In the method, certainly in this cellulose suspension, add other component.The example of these components comprises conventional fillers, fluorescent whitening agent, sizing agent, dry strength agent, wet strength agent etc.The example of suitable conventional fillers comprises kaolin, potter's clay, titanium dioxide, gypsum, talcum, natural and synthetic calcium carbonate, for example the aluminium oxide of chalk, the marble that grinds and winnofil, hydrogenation (three aluminium hydroxide), calcium sulfate, barium sulfate, calcium oxalate etc.The example of suitable sizing agent comprises the cellulose reactive sizing agent of tool not, for example based on the sizing agent of rosin, for example based on the soap of rosin, based on the emulsion/dispersion liquid of rosin, with cellulose is had reactive sizing agent, the emulsion/dispersion liquid of acid anhydrides (for example alkenyl succinic anhydride ASA), thiazolinyl and alkyl ketene dimer (AKD) and polymer for example.The example of suitable wet strength agent comprises polyamine and polyaminoamide.

The present invention further comprises paper process, wherein the plain boiled water height reclaims or recirculation, promptly has high whitewater closure degree, for example wherein whenever makes one ton of dried paper, use 0 to 30 ton of fresh water, common paper per ton less than 20, preferably less than 15, be more preferably less than 10, especially less than 5 tons fresh water.Can introduce fresh water in any stage in the method; For example, fresh water can be mixed forming cellulose suspension with cellulose fibre, and fresh water can be mixed with dense cellulose suspension so that its dilution is formed rare cellulose suspension.

Method of the present invention is used to make cellulose product, preferred paper.Term used herein " paper " not only comprises paper and manufacturing thereof, also comprises other width of cloth shape product (for example plate and cardboard) and manufacturing thereof.This method can be used for by above-mentioned dissimilar cellulose fibre suspension papermaking, and this suspension should preferably contain by dry 25%, more preferably this fibrid of at least 50 weight % at least.

The present invention preferably is used in and makes on the paper contain timber and the paper machine based on the paper of recycled fiber (for example SC, LWC) and dissimilar book printing paper and newsprint, with be used on the machine of making no wooden printing and writing paper, term does not have wooden meaning and is less than about 15% the wooden fiber that contains.The example of preferable use of the present invention comprises the layer of being made paper and multi-ply paper at least by the cellulose suspension of machinery that contains 50 weight % and/or recycled fiber.This method preferably be used in 300 to 3000 meters/minute, more preferably on 500 to 2500 meters/minute the paper machine of speed operation.

Further set forth the present invention in the following example, still, they are not to limit the present invention.Unless indicate separately, umber and % relate separately to weight portion and weight %.

Embodiment 1

By can be available from Akribi Kemikonsulter AB, the dynamic drainage analyzer of Sweden (Dynamic Drainage Analyser) (DDA) is evaluated and tested the moisture energy of filter that this method realizes, this analyzer measure remove stopper and to the opposite one side of the one side with there being cellulose suspension of forming web on set time of water slurry of the cellulose fiber of volume when applying vacuum (0.35 crust) via the forming web leaching.Evaluate and test retention by nephelometer one time by the turbidity of the filtrate (plain boiled water) of measuring leaching suspension and getting.Turbidity is measured with NTU (Nephelometric Turbidity Units).NTU is high more, and the material of keeping is few more.

The derive mixture of self-heating mechanical pulp (TMP) (70%) and Stone Ground Wood (SGW) (30%) of used cellulose suspension, it is by hydrogen peroxide/sodium metasilicate bleaching.This suspension is diluted with water to 4% fibre concentration, and comprises the mixture process of alum and magnesium sulfate salt in order to 35: 1.87 weight ratio.After the processing, by adding sulfuric acid (H ₂SO ₄) the pH value is reduced to about 5, and kept 30 minutes at 40 ℃.Then this suspension is diluted with water to 1 weight % fibre concentration, and makes the pH value remain on 5 by before carrying out the DDA test, adding extra sulfuric acid.

This sample is packed in the DDA jar of being with baffle plate.Following adding retention and dehydrating agent:

I) before leaching suspension 15 seconds, the cationic-type polyacrylamide of various amounts (Eka PL1510).

Ii) before leaching suspension 5 seconds, the anionic silica-based particles of 0.5 kg/ton (Eka NP 320).

In all embodiments, amount is based on the dry weight of cellulose suspension, and ton is meant metric ton.Test 1-3,5-7,9, be used for comparison 10 and 12 to No. 18, and test the 4th, 8 and No. 11 demonstration by handle the result who gets according to the present invention.

Table 1

Tested number	The interpolation of alum [kg/ton]	Mixture (alum: MgSO 4) interpolation [kg/ton]	The interpolation of cation type polymer [kg/ton]	Drainage time [s]	Turbidity [NTU]
						1	0	0	0.5	19.3	214
2	15	0	0.5	17.9	214
						3	35	0	0.5	15.0	196
4	0	35∶1.87	0.5	12.0	176
						5	0	0	1.0	15.3	205
6	15	0	1.0	15.3	197
						7	35	0	1.0	11.9	172
8	0	35∶1.87	1.0	9.3	124
						9	15	0	1.25	14.7	190
10	35	0	1.25	10.5	148
						11	0	35∶1.87	1.25	7.1	101
12	0	0	1.5	14.4	165
						13	15	0	1.5	14.0	190
14	35	0	1.5	9.2	126
						15	0	0	2.0	12.2	146

16	15	0	2.0	10.5	164
						17	0	0	3.0	9.6	121
18	15	0	3.0	8.2	137

The result who lists from table 1 compares with the suspension of not handling fully with the suspension of only handling with alum with the suspension of alum and magnesium sulfate processing according to the present invention as can be seen, has produced better drainage and retention performance.

Embodiment 2

In this embodiment, according to general procedure evaluation and test drainage and the retention performance of embodiment 1, different is also to use cationic coagulating agent.Cationic coagulating agent of following interpolation and retention chemical conditioner:

I) before leaching suspension 30 seconds, the cationic-type polyacrylamide coagulating agent of various amounts (EkaATC 5439);

Ii) before leaching suspension 15 seconds, the cationic-type polyacrylamide of 0.5 kg/ton helped filter retention agent (Eka PL 1510)

Iii) before leaching suspension 5 seconds, the dry pulp of the anionic silica-based particles of 0.5 kg/ton (Eka NP 320).

Test 19-21,24-26,28-30 and 32-34 number and be used for comparison, and test the demonstration treatment in accordance with the present invention the 22nd, 23,27 and No. 31.

Table 2

Tested number	The interpolation of alum [kg/ton]	Mixture (alum: MgSO 4) interpolation [kg/ton]	The interpolation of cationic coagulating agent [kg/ton]	Drainage time [s]	Turbidity [NTU]
						19	0	0	0	19.3	214
20	15	0	0	15	214
						21	35	0	0	17.9	196
22	0	35∶1.87	0	12	176
						23	0	35∶1.87	0.25	11	130

24	0	0	0.5	16.1	200
						25	15	0	0.5	11.3	202
26	35	0	0.5	15.3	160
						27	0	35∶1.87	0.5	8.8	99
28	0	0	0.75	15.7	178
						29	15	0	0.75	9.9	200
30	35	0	0.75	14.9	129
						31	0	35∶1.87	0.75	7.3	85
32	0	0	1.0	14.2	171
						33	15	0	1.0	8.5	178
34	35	0	1.0	13.8	103

The result who lists from table 2 compares with the suspension of not handling fully with the suspension of only handling with alum with the suspension of alum and magnesium sulfate processing according to the present invention as can be seen, has produced drainage and retention performance preferably.

Embodiment 3

In this embodiment, the yield of evaluation and test this method when using the composition that comprises alum and magnesium sulfate of the present invention.

Large batch of hydrogen peroxide/sodium metasilicate TMP bleaching/SGW is diluted with water to 4% fibre concentration.This batch of material is fully mixed and is divided into the quartering.Handle gained suspension by different way.But, dilute all suspension in the mode of unanimity, and the heavy change of evaluation and test paper substrate.The processing of suspension is listed in the table 3.

Table 3

Tested number	Handle
		1	Non-processor.By adding sulfuric acid, the pH value is reduced to 5, and kept 30 minutes at 40 ℃.To set volume suspension concentration is reduced to 1% then.In all tests, use and set volume, to reach 1%.
2	Handle under 4% pulp density with alum.Be metered into 35 kg/ton alum, and the pH value be adjusted to 5 by adding sulfuric acid.Then it was kept 30 minutes at 40 ℃, then according to test 1 dilution.
		3	Handle under 4% pulp density with the mixture that comprises alum and magnesium sulfate.This mixture mixes with following ratio: effective dose is 35 kg/ton alum and 1.87 kg/ton magnesium sulfate, and by adding sulfuric acid the pH value is adjusted to 5.Then it was kept 30 minutes at 40 ℃, then according to test 1 dilution.
4	Handle under 1% pulp density with the mixture that comprises alum and magnesium sulfate.This mixture mixes with following ratio: effective dose is 35 kg/ton alum and 1.87 kg/ton magnesium sulfate, and by adding sulfuric acid the pH value is adjusted to 5.Then it was kept 30 minutes at 40 ℃.

All four kinds of samples all have identical setting dilution factor, and do not compensate the solid content variation.Prepare hand-made paper according to the method described in the SCAN-CN 64:00, and use 5 kg/ton cationic starch as helping the filter retention agent.Under plain boiled water recirculation, make 25 paper.Use last 10 paper evaluation and test gained yield.To evaluate and test the raising of inorganic yield by the increase of the content of ashes evaluated and tested out according to the method for ISO 2144-1977.The results are shown in the table 4.

Table 4

From table 4 listed result as can be seen, the paper process of alum used according to the invention and magnesium sulfate (test 3) has improved the yield of this method.

Embodiment 4

In this embodiment, evaluation and test paper product matter aspect basic weight, content of ashes, thickness, density, apparent density, tensile figure, tear index, gas permeability, brightness, opacity, light scattering and light absorption.Between from the paper that the water-containing pulp suspension of bleaching and bleached pulp is not made, comparing.Pulp treatment suspension by different way.Suspension is available from the TMP/SGW (70/30) of TMP/SGW (70/30) or hydrogen peroxide/sodium metasilicate bleaching.Suspension in the test do not handle fully, handle or with alum, magnesium sulfate and acid treatment with calcined clay.When the conduct of adding cationic starch helps the filter retention agent in suspension, further compare in a similar manner.Use standard method SCAN-CM 64:00 to prepare paper.The processing of suspension is listed in the table 5.

Table 5

Tested number	Handle
		1	Unbleached TMP/SGW
2	The TMP/SGW of hydrogen peroxide/sodium metasilicate bleaching
		3	The TMP/SGW of hydrogen peroxide/sodium metasilicate bleaching based on the dry weight of suspension, adds the calcined clay of 2.5 weight % in fibre concentration is the dilution cellulose suspension of 1 weight %.
4	The TMP/SGW of hydrogen peroxide/sodium metasilicate bleaching based on the dry weight of suspension, adds the calcined clay of 5.0 weight % in fibre concentration is the dilution cellulose suspension of 1 weight %.
		5	The TMP/SGW of hydrogen peroxide/sodium metasilicate bleaching handles under 4% pulp density with the mixture that comprises alum and magnesium sulfate.This mixture mixes with following ratio: effective dose is 35 kg/ton alum and 1.87 kg/ton magnesium sulfate, and by adding sulfuric acid the pH value is adjusted to 5.Then it was kept 30 minutes at 40 ℃, be diluted to the fibre concentration of 1 weight % then.
6	The TMP/SGW of hydrogen peroxide/sodium metasilicate bleaching, the cationic starch of 20 seconds adding 5 kg/ton before drainage.

7	The TMP/SGW of hydrogen peroxide/sodium metasilicate bleaching, dry weight based on suspension, to fibre concentration is the calcined clay that adds 2.5 weight % in the dilution cellulose suspension of 1 weight %, adds the cationic starch of 5 kg/ton before drainage in 20 seconds.
		8	The TMP/SGW of hydrogen peroxide/sodium metasilicate bleaching, dry weight based on suspension, to fibre concentration is the calcined clay that adds 5.0 weight % in the dilution cellulose suspension of about 1 weight %, adds the cationic starch of 5 kg/ton before drainage in 20 seconds.
9	The TMP/SGW of hydrogen peroxide/sodium metasilicate bleaching handles under 4% pulp density with the mixture that comprises alum and magnesium sulfate.This mixture mixes with following ratio: effective dose is 35 kg/ton alum and 1.87 kg/ton magnesium sulfate, and by adding sulfuric acid the pH value is adjusted to 5.Then it was kept 30 minutes at 40 ℃, be diluted to the fibre concentration of 1 weight %, before drainage, added the cationic starch of 5 kg/ton then in 20 seconds.

According to standard ISO 536:1995 evaluation and test basic weight, according to ISO 2144-1977 evaluation and test content of ashes, according to ISO 534:1988 evaluation and test thickness, apparent density and density, according to SCAN-P kN/kg evaluation and test in 67: 93 tensile figure, according to ISO 1974:1990 evaluation and test tear index, and according to ISO 5636-5:2003 evaluation and test gas permeability.

Table 6

Tested number	Basic weight [g/m 2]	Content of ashes [%]	Thickness [μ m]	Density [kg/dm 3]	Apparent density [dm 3/kg]	Tensile figure [kN/kg]	Tear index [mNm 2/g]	Gas permeability [s]
									1	59.38	0.43	169	351	2.85	18.4	2.97	9.0
2	62.35	1.01	175	356	2.81	21.0	3.74	31.4
									3	59.14	1.51	174	349	2.87	21.0	3.48	22.0
4	60.67	2.12	172	344	2.91	19.2	3.69	22.3
									5	58.64	2.85	175	335	2.98	17.2	3.35	13.6
6	64.83	1.24	178	364	2.75	20.9	3.48	23.0
									7	63.93	3.01	174	371	2.70	20.1	3.35	26.9
8	64.49	4.78	173	370	2.71	20.4	3.53	22.5
									9	62.84	3.41	177	355	2.82	20.9	3.43	12.1

Also aspect brightness, opacity, light scattering and light absorption, evaluate and test paper product matter.Measure by equipment Technidyne.Colour Touch and according to following standard: according to ISO 2470 measurement brightness, according to ISO 2471 measurement for opaque degree, according to ISO 9416 measuring light scattering and light absorption.

Table 7

Tested number	Brightness [%]	Opacity [%]	Light scattering [m 2/kg]	Light absorption [m 2/kg]
					1	58.97	93.40	55.15	2.64
2	75.31	86.23	54.21	0.49
					3	75.37	86.94	57.16	0.58
4	75.71	86.80	58.48	0.61
					5	76.12	86.04	56.96	0.52
6	75.00	88.24	57.22	0.62
					7	75.90	89.24	61.86	0.62
8	77.26	90.09	67.86	0.63
					9	75.84	88.07	58.70	0.64

From table 6 and 7 listed result as can be seen, roughly the same or even the better paper characteristic of the paper that the paper process that test shows and use calcined clay to make additive 9 (wherein the method according to this invention prepares paper) is made.

Claims (32)

1. make the method for cellulose product, it comprises:

(i) provide the moisture dense suspension of the fibre concentration cellulose fiber, that have about at least 2 weight %;

(ii) in this dense suspension, add:

(I) aluminium compound;

(II) alkali salt;

(III) acid;

(iii) the gained dense suspension is diluted to form dilute suspension;

(iv) in this dilute suspension, add one or more and help the filter retention agent; With

(v) the gained dilute suspension is dewatered.

2. make the method for cellulose product, it comprises:

(i) provide the moisture dense suspension of cellulose fiber, this dense suspension has:

(a) fibre concentration of about at least 2 weight %;

(b) the alkaline-earth metal ions concentration of about at least 100 mg/litre;

(ii) in this dense suspension, add aluminium compound and randomly add sour, to obtain about 4 to about 5.5 pH value;

(iii) the gained dense suspension is diluted to form dilute suspension;

(iv) in this dilute suspension, add one or more and help the filter retention agent; With

(v) the gained dilute suspension is dewatered.

3. according to claim 1 or 2 each methods, wherein said aluminium compound is alum, aluminium polychloride, poly aluminium sulfate silicate, aluminate, aluminum nitrate or their mixture.

4. according to each method of claim 1 to 3, wherein alkali salt is added in the described dense suspension to obtain the alkaline-earth metal ions concentration of at least 100 mg/litre.

5. according to each method of claim 1 to 4, wherein said alkali salt is magnesium, calcium or barium salt.

6. according to each method of claim 1 to 5, wherein alkali salt has the halogen of being selected from ion, sulfate radical, carbonate, nitrate radical or organic acid anion.

7. according to each method of aforementioned claim, wherein said alkali salt is magnesium chloride, magnesium sulfate, calcium chloride or barium sulfate.

8. according to each method of aforementioned claim, wherein said acid is inorganic acid.

9. according to each method of aforementioned claim, wherein said acid is hydrochloric acid or sulfuric acid.

10. according to each method of aforementioned claim, wherein acid is added in the dense suspension pH value to obtain about 4 to about 5.5.

11., wherein after adding aluminium compound, alkali salt and acid, the pH value of dense suspension is brought up to about 6 to about 8 by adding alkali according to each method of aforementioned claim.

12. according to each method of aforementioned claim, wherein said dense suspension has the fibre concentration of about at least 3.5 weight %.

13. according to each method of aforementioned claim, wherein said dense suspension contains the cellulose fibre derived from mechanical pulp.

14. according to the method for claim 13, wherein said mechanical pulp is a hydrogen peroxide bleaching.

15. according to each method of aforementioned claim, wherein:

(I) aluminium compound;

(II) alkali salt; With

(III) acid;

Added in the suspension respectively.

16. according to each method of aforementioned claim, wherein:

(I) aluminium compound;

(II) alkali salt; And/or

(III) acid;

Add in the suspension with form of mixtures.

17. according to each method of aforementioned claim, the wherein said filter retention agent that helps comprises one or more cationic organic polymers.

18. according to each method of aforementioned claim, the wherein said filter retention agent that helps comprises siliceous material.

19. according to each method of aforementioned claim, the wherein said cationic organic polymer that helps the filter retention agent to be included in to add before the shear stage and the siliceous material of interpolation shear stage after.

20. according to each method of aforementioned claim, the wherein said filter retention agent that helps comprises the anionic silica-based particles.

21. according to each method of aforementioned claim, wherein said cellulose product is a paper.

22. according to each method of aforementioned claim, wherein the method for this manufacturing cellulose product is being carried out in comprehensive paper mill.

23. an Aquo-composition, it comprises following mixtures of material:

(I) aluminium compound;

(II) alkali salt; With

(III) acid;

Wherein the weight ratio of aluminium compound, alkali salt and acid is about 60: 1: 0.1 to about 5: 1: 1.

24. according to the composition of claim 23, wherein said aluminium compound is alum, aluminium polychloride, poly aluminium sulfate silicate, aluminate, aluminum nitrate or their mixture.

25. according to the composition of claim 23 or 24, wherein said acid is inorganic acid.

26. according to each composition of claim 23 to 25, wherein said acid is hydrochloric acid or sulfuric acid.

27. according to each composition of claim 23 to 26, wherein said salt is magnesium, calcium or barium salt.

28. according to each composition of claim 23 to 27, wherein said salt has the halogen of being selected from ion, sulfate radical, carbonate, nitrate radical or organic acid anion.

29. according to each composition of claim 23 to 27, wherein said salt is magnesium chloride, magnesium sulfate, calcium chloride or barium sulfate.

30. according to each the purposes of Aquo-composition of claim 23 to 29, as the additive in the method for making cellulose product.

31. according to the purposes of claim 30, wherein said composition is as helping the filter retention agent in the method for making cellulose product.

32. according to the purposes of claim 30 or 31, wherein said composition with comprise at least a cationic polymerization retention agent one or more help the filter retention agent to be used in combination.