KR0162252B1 - Controlling deposits on paper machine felts and composition - Google Patents

Abstract

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Description

Methods and Compositions for Inhibiting Deposits in Paper Machines

1 is a schematic side elevational view of a felt in a paper machine that can be treated in accordance with the present invention.

2 is a schematic side elevational view of a felt in a batt forming paper machine that can be treated in accordance with the present invention.

The present invention relates to the provision of a clean sheet felt device for paper making and more particularly to the chemical treatment of paper machine felt for controlling the deposition of the adhesive material on the paper machine felt.

Papermaking typically involves processing a carefully prepared aqueous fiber suspension to produce a highly uniform dry paper sheet. The three steps involved in this typical process include a sheet forming step in which the suspension is placed on a porous mesh or wire on which liquid passes through the wire while the fibers are deposited, and the resulting sheet is passed through a compressor covered with porous felt and contained in the sheet. The sheet processing step of extracting the moisture to improve the uniformity of the sheet and impart the surface characteristics to the sheet, and the paper drying step of evaporating the remaining water from the sheet. This sheet can be further processed into a finished paper product.

Evaporating water is known to be relatively expensive because it is energy intensive. Effective papermaking thus relies on extracting water during the forming and compacting process and eliminating sheet bonds that make the drying sheet unsuitable for use. Felts and wires are therefore particularly important because they are in intimate contact with the sheet, affecting not only the water removal but also the quality of the sheet itself. Deposits collected on the felt or wire may adversely affect the water removal efficiency, puncture the sheet and may be transferred to the sheet material resulting in defects.

The quality of the aqueous fiber suspension used to make the sheet depends on many factors, including the wood and water used as raw materials, the composition of the recycled raw materials added to the process and the additives used during the preparation of the suspension. Therefore, various dissolved or suspended substances, including inks, latex and adhesives from recycled paper products, as well as inorganic materials such as salts and clays, and organic materials such as resins or pitches from wood, can be introduced into this manufacturing process. Can be. Accumulation of deposits containing inorganic and / or organic materials on felt and other sheet forming apparatus during this manufacturing process is a problematic obstacle to effective grassland. Particularly difficult are adhesive materials such as adhesives, resins, rubbers, and the like associated with recycled fibers.

The rapid and effective removal of these deposits from the sheet forming apparatus of the paper machine is of great industrial importance. The paper machine can be shut down for cleaning, but it is not desirable to stop the work for cleaning because of the reduced productivity. Therefore, on-line cleaning performed while producing effectively is very desirable.

The wire belt or cylinder used for sheet forming circulates continuously as a belt during production. The sheet contact area starts where the addition of the fiber suspension to the wire belt or cylinder begins and continues until the molded sheet is separated from the wire surface. The conveying area also returns the wire from the position where the molded sheet is removed from its surface to the beginning of the sheet contact area. In the case of wire belts such as Fourdrinier wires, on-line wire cleaning is often performed by treating the conveying wire with a cleaning liquid (typically water) during the conveying step (ie when the wire is not in contact with the forming sheet). Is carried out by showering with liquid under pressure. The shower can be performed with the aid of a mechanical surface wash. It has been found that using a water shower with or without assistance is not sufficient to prevent the accumulation of organic compounds or inorganic deposits on the wire, and additional materials have been used to provide more effective cleaning nuclei. Water-based materials containing acids or alkalis in combination with other compounds such as surfactants have been used to successfully remove mainly fiber or inorganic materials. When organic deposits predominate, they have been successfully removed to some extent by using organic solvents containing aromatic compounds having a low flash point or chlorine and hydrocarbon containing materials. In some machines microporous woven belts have recently been used instead of conventional wires.

The paper machine felt also circulates continuously on the belt between the sheet contacting step and the conveying step. During the sheet contacting phase, water is usually extracted from the sheet with the aid of pressure and / or vacuum and enters the pores of the felt. Clean felts having relatively open micropores are particularly preferred for the papermaking process because they effectively remove water from the paper sheet. The felt cleaning process must remove organic and inorganic deposits of general and local properties, maintain felt porosity and control the nap of the woven fabric without chemical or physical damage to the substrate. Typically mechanical removal by blade contact has been used to remove debris from the felt surface. But also cleaning fluids are used to remove the annoying organic and inorganic deposits. The fabric composition and structure of numerous paper machine felts make the felt prone to chemical degradation. The cleaning agent should also be easily removed by rinsing off. Most paper machines use both continuous and impact cleaning. Chemicals used include organic solvents, often chlorine and hydrocarbons. Acid and alkali based instruments are also used but at lower concentrations than those used for wire cleaning. Alkali metal hydroxides of too high concentration are unsuitable for felt cleaning because they invade the woven material.

Some of the more successful organic solvents have been defined as hygienic hazards such as carcinogens and therefore require special handling precautions. Products based on other solvents can damage the plastic or rubber components used in the paper forming process. One of the on-line treatments of felts that have been used successfully for some years is the use of aqueous cationic surfactant solutions such as alkyldimethyl benzyl ammonium chloride in which the alkyl group is a mixture of C ₁₂ H ₂₅ , C ₁₄ H ₂₉ and C ₁₆ H ₃₃ groups. Contacting the felt. Experience has shown, however, that even with these surfactants, certain sticky materials tend to stick to the felt. Another method of felt treatment that is preferred in the past is to add an aqueous cationic polymer solution to the felt. However, this treatment form may result in deposit accumulation from the cationic polymer itself.

Other sheet forming devices such as deckers, filters, screens and rolls may also be contaminated. Process issues and their handling are largely similar to felt devices, but certain considerations, such as maintaining the porosity and preventing chemical degradation of the woven fabric, which are important in felt cleaning and certain microporous device cleaning, are not so important for other devices.

Natural resins or gums in fresh wood may vary from species to species. Certain types of pine, especially pines containing more than 2% by weight of resin, are commonly used in very low percentages due to the rubber and resin problems they cause. Grasslanders have traditionally used alum or sodium aluminate to control natural hardwood deposits. These materials are added to the entire pulp system to suppress the deposition of resin on the fibers. The efficiency of this method is limited by factors such as pH, corrosion potential, paper sheet forming, and the need to adjust the interaction with other chemicals in the pulp system. Treatments that do not limit the use of pine sources in these problems provide significant economic benefits for pulp and paper producers.

The use of recycled fibers has become more common, leading to more serious accumulation of sticky material during paper molding. The adhesives, resins and rubbers found in the recycled secondary fibers tend to stick to various parts of the paper machine and also tolerate on-line sash cleaning. Material sticking to the felt can have a serious impact on drainage and paper forming. In the end, they cause holes in the product and in some cases tear the sheet during paper processing. It may be necessary to stop the work frequently to solvent wash the felt, particularly to remove sticky material associated with the regenerated fibers. The benefits of paper recycling can be offset in part by the reduced productivity of the paper machine.

Certain organic cleaners commonly used in the past have become environmentally undesirable. Thus, there has been a great need for cleaners to remove organic deposits without harming the environment. Naturally, the materials used should not break felt or other sheet forming apparatus. While it is known that certain materials can be run satisfactorily under certain conditions, there is still a need for more effective deposit inhibitors for paper molding, particularly paper molding in which recycled fibers are used as raw materials.

Another method for deposit inhibition is to use pulp additives such as anionic aryl sulfonic acid-formaldehyde condensates or cationic dicyandiamide-formaldehyde condensates. These additives may act as metal ion sequestrants, dispersants or surfactants. In particular, cationic dicyandiamide-formaldehyde aminoplast resins are known to adhere pitch to pulp fibers in a discontinuous position such that the pitch particles are evenly distributed over the fibers. Thus, the amount of pitch accumulated in the paper machine is said to be reduced without causing dark spots or small spots on the paper product.

The inventors have found that depositing adhesive material from the paper pulp onto paper machine felt and other paper making devices used to process the pulp slurry into sheets adds an aqueous solution containing at least about 2 ppm of cationic polymer to the device and from the cationic polymer. It was found that an aqueous solution containing a compound selected from the group consisting of an effective amount of water-soluble nonionic and cationic surfactants for inhibiting the formation of derived deposits can be suppressed by adding to the device. Preferably, aqueous solutions containing cationic polymers and surfactants are substantially free of anionic polymers. Preferred cationic polymers include quaternary ammonium polymers such as protonated polymers or polymers formed by reacting epihalohydrin with dimethylamine or diethylamine. Preferred cationic surfactants include alkyldimethyl benzyl ammonium chloride having alkyl groups between about 12 and 16 carbon atoms. The invention is particularly advantageous when used to treat felt and similar device parts used when processing pulp slurry into sheets.

One object of the present invention is to provide a method capable of effectively suppressing deposition of materials in a paper forming apparatus.

Another object of the present invention is to provide a paper machine deposition suppression method for improving papermaking efficiency using recycled or resin-rich pine pulp fibers.

It is yet another object of the present invention to provide an environmentally acceptable method for suppressing paper machine deposition.

It is yet another object of the present invention to provide a means for improving productivity and product quality in papermaking processes.

These and other objects and advantages of the present invention will become apparent from the following detailed description of the invention.

The present invention relates to aqueous solutions of certain water soluble cationic polymers and certain water soluble surfactants for substantially suppressing the deposition of organic and inorganic deposits on felt or other sheet forming devices, in particular other microporous parts of such devices. Treatment using cationic polymers in combination with cationic surfactants can effectively inhibit deposition on the treatment apparatus even if the recycled fibers make up a significant portion of the pulp material. The present invention provides a felt cleaner and conditiony that is particularly effective for paper machines.

The present invention can be used in a variety of different polymers as long as they are generally applicable and cationic with respect to the detailed properties of the polymer. The use of polyethyleneimine results in the use of various polymeric materials containing amino groups such as those prepared according to the methods described in US Pat. No. 3,250,664, US Pat. No. 3,642,572, US Pat. No. 3,893,885 or US Pat. It is within the scope of the invention. However, it is generally preferred to use protonated or quaternary ammonium polymers. These preferred polymers include polymers obtained by reaction between epihalohydrin and one or more amines, and polymers derived from ethylenically unsaturated monomers containing quaternary ammonium groups. Cationic polymers of the present invention also include dicyandiamide-formaldehyde condensates. Polymers of this type are described in US Pat. No. 3,582,461 and incorporated herein intact. Either of formic acid or ammonium salts, and most preferably both formic acid and ammonium chloride may be included as polymerisation. However, some dicyandiamide-formaldehyde condensates tend to aggregate on the felt even in the presence of cationic surfactants. One of the dicyandiamide-formaldehyde polymers is commercially available from Tinofix QF, manufactured by Ciba-Geigy Chemical Limited, Ontario, Canada, which is about 50% by weight polymer having a molecular weight ranging from about 20,000 to 50,000 as an active ingredient. Contains%

Quaternary ammonium polymers derived from epihalohydrin and various amines are obtained by reaction with at least one amine selected from the group consisting of epichlorohydrin dimethylamine, ethylenediamine and polyalkylenepolyamines. Triethanolamine can also be included in the present invention. Examples include polymers obtained by reaction with polyalkylene polyamines and epichlorohydrin as well as polymers obtained by reaction with epichlorohydrin, dimethylamine and one of ethylenediamine or polyalkylene polyamines. Typical amines that can be used are ethylene diamines used with dimethylamine and triethanol amines as well as N, N, N ', N'-tetramethylethylene-diamine. Polymers of this type include polymers of the general formula: and other amines may also be used.

Wherein A is 0 to 500.

Preferred cationic polymers of the present invention include those obtained by reacting dimethylamine, diethylamine, or methylethylamine, preferably dimethylamine or diethylamine with epihalohydrin, preferably epichlorohydrin. do. Polymers of this type are described in US Pat. No. 3,738,945 and Kenya Patent No. 1,096,070 and are incorporated herein intact. Such polymers are commercially available as Agefloc A-50, Agefloc A-50HV and Agefloc B-50 from CPS Chemical Company Limited, New Jersey, USA. These three products contain, as active ingredients, about 50% by weight polymer, each having a molecular weight of about 75,000 to 80,000, about 200,000 to 250,000, and about 20,000 to 30,000. Other commercially available products of this release are Magnifloc 573C manufactured by American Cyanamide Campanile, New Jersey, USA, which is believed to contain 50% by weight of a polymer having a molecular weight of about 20,000 to 30,000 as active ingredient.

Typical cationic polymers which can be used according to the invention and derived from ethylenically unsaturated monomers are vinyl pyridine and vinyl which can be quaternized with C ₁ to C ₁₈ alkyl halides, benzyl halides, especially chloride or dimethyl or diethyl solphate. Imidazole, or a general formula NR ₁ R ₂ wherein R ₁ , R ₂ and R ₃ are independently of each other lower alkyl having 1 to 4 carbon atoms, and one of R ₁ , R ₂ and R ₃ is C ₁ -C ₁₈ alkyl Homo- and copolymers of vinyl compounds such as vinyl benzyl chloride which may be quaternized with tertiary amines of R ₃ ; Allyl compounds such as diallyldimethyl ammonium chloride; Or C ₁ to C ₁₈ alkyl halides, benzyl halides or diethylsulfate, methacrylamido propyl tri (C ₁ to C ₄ alkyl, especially methyl) ammonium salts or (meth) acryloyloxyethyl tri (C ₁ to C ₄ With alkyl, especially methyl) ammonium salts, where the salts are quaternized with halides, in particular chloride, methosulfate, etosulphate or n- is 1 / n of the anion) Such as acrylic derivatives. These monomers can be copolymerized with (meth) acrylic acid derivatives such as acrylamide, acrylate or methacrylate C ₁ -C ₁₈ alkyl esters or acrylonitrile or alkylvinyl ethers, vinyl pyrrolidone or vinyl acetate. Typical such polymers contain from 10 to 100 mole percent of repeating units of the formula and from 0 to 90 mole percent of repeating units of the formula

Wherein R ₁ is hydrogen or a lower alkyl radical of typically 1 to 4 carbon atoms, R ₂ is typically a long chain alkyl group of 8 to 18 carbon atoms, and R ₃ , R ₄ and R ₅ are independently hydrogen Or a lower alkyl group, X is an anion, typically a halide ion, a methosulfate ion, an etosulphate ion or n is 1 / n of an anion.

Other quaternary ammonium polymers derived from unsaturated monomers include homopolymers of diallyldimethyl ammonium chloride comprising repeating units of the general formula:

In this connection it should be noted that these polymers contain cyclic groups, but because these groups are connected in a straight chain, there is no crosslinking and therefore they should be regarded as substantial straight chains.

Other polymers that can be used and can be derived from unsaturated monomers include polymers having the structure

Wherein Z and Z 'are the same or different, -CH ₂ CH-CHCH ₂ -or -CH ₂ -CHOHCH _2- , Y and Y' are the same or different and X or -NR'R '', X is halogen of at least 30 atomic weights, n is an integer from 2 to 20, and R 'and R''are (i) the same or different and an alkyl group of 1 to 18 carbon atoms optionally substituted with 1 to 2 hydroxy groups Or (ii) a saturated or unsaturated ring of 5 to 7 atoms in combination with N, or (iii) an N-morpholino group in combination with N and an oxygen atom.

Especially preferred of such polymers are poly (dimethylbutenyl) ammonium chloride bis- (triethanol ammonium chloride).

Other examples of polymers that can be derived and used from ethylenically unsaturated monomers include polybutadiene in which some of the dialkyl amino groups resulting from reaction with lower alkyl amines are quaternized. Therefore, in general, this polymer contains a repeating monomer of the following structural formula in a: b ₁ : b ₂ : c molar ratio.

Wherein R is a lower alkyl radical, typically a methyl or ethyl radical. Lower alkyl radicals need not all be identical. Typical quaternization agents include methyl chloride, dimethyl sulfate, and diethyl sulfate. The change ratio of a: b ₁ : b ₂ : c may be used such that the amount of amine (b ₁ + b ₂ ) is generally 10 to 90% and (a + c) is 90% to 10%. These polymers can be obtained by reacting polybutadiene with carbon monoxide and hydrogen in the presence of a suitable lower alkylamine.

Other cationic polymers that can interact with anionic polymers and / or tacky materials in paper pulp can be used within the scope of the present invention. These are polyamide amines crosslinked with epichlorohydrin as well as cationic tannin derivatives formed from acetate, formate, hydrochloride or quaternized salts in a Mannich type reaction (condensed polyphenol form) of tannins with formaldehyde and amines. Crosslinked polyamine polymers, such as / polyethylene polyamine copolymers. Natural rubber and starch modified to include cationic groups are also useful.

Although the molecular weight of the most useful polymers of the present invention is generally between about 2,000 and about 3,000,000, polymers having molecular weights of up to 2000 and more than 3,000,000 can also be used successfully. The preferred molecular weight of the polymer used is at least about 10,000, and most preferably at least about 20,000. Preferably the polymer used has a molecular weight of about 300,000 or less, and most preferably about 50,000 or less. Most preferred polymers have a molecular weight in the range of about 20,000 to about 50,000. Mixtures of these polymers can also be used.

The present invention has general applicability with regard to the detailed properties of nonionic and cationic surfactants that can be used and as long as they are water soluble, several different surfactants can be used in combination with the polymer component. Suitable nonionic surfactants include hydrogenated molecules such as higher fatty acid alcohols, higher fatty acids, alkylphenols, polyethylene glycols, long chain fatty acid esters, polyhydric alcohols and their partial fatty acid esters, and partially esterified or etherified long chain polyglycols. And condensation products with ethylene oxide. Combinations of these condensation products can also be used.

Cationic surfactants are generally preferred. Particularly preferred cationic surfactants for use in the present invention include water-soluble surfactants having a molecular weight between about 200 and 800 and having the following structural formula.

Wherein R is independently selected from the group consisting of hydrogen, polyethylene oxide groups, polypropylene oxide groups, alkyl groups having from about 1 to 22 carbon atoms, aryl groups and aralkyl groups, at least one of which is about 8 An alkyl group having at least carbon atoms and preferably an n-alkyl group having from about 12 to 16 carbon atoms, and X is an anion, typically a halide ion (e.g. chloride), or n- is 1 / n of an anion. Mixtures of these compounds can also be used as surfactants of the invention.

및

로부터 선정되고 가장 바람직하게는 벤질이다. 특히 유용한 계면활성제는 약 12 내지 16개 탄소원자 사이의 알킬기를 갖는 알킬 디메틸벤질 암모늄 클로라이드를 포함한다. 이 형의 시판되고 있는 제품의 하나는 계면활성제의 약 50%가 C₁₄H₂₉n-알킬기를 갖고, 계면활성제의 약 40%가 C₁₂H₂₅n-알킬기를 가지며 또 계면활성제의 약10%가 C₁₆H₃₃n-알킬기를 갖는 알킬 디메틸 벤질 암모늄 클로라이드의 혼합물을 포함한다. 이 제품은 살균 작용으로도 공지되어 있다.The two R groups of the cationic surfactant of the above structural formula are preferably selected from the group consisting of methyl and ethyl, most preferably methyl, and preferably one aralkyl group

And

And most preferably benzyl. Particularly useful surfactants include alkyl dimethylbenzyl ammonium chlorides having alkyl groups between about 12 and 16 carbon atoms. One commercially available product of this type has about 50% of the surfactant having C ₁₄ H ₂₉ n-alkyl groups, about 40% of the surfactant having C ₁₂ H ₂₅ n-alkyl groups and about 10% of the surfactant And a mixture of alkyl dimethyl benzyl ammonium chlorides having a C ₁₆ H ₃₃ n-alkyl group. This product is also known for its bactericidal action.

Surfactants suitable for use in the present invention have a molecular weight of between about 1000 and about 26,000, R ₁ and R ₂ are polyethylene oxide, polypropylene oxide or a combination of ethylene oxide and propylene oxide, and R ₃ is a polyether, alkyl group. Or a group of pseudo cationic materials, the general formula (NR ₁ R ₂ R ₃ ) selected from the group consisting of hydrogen. Examples of surfactants of this type are described in US Pat. No. 2,979,528.

The addition of cationic polymers of the present invention to the felt together with nonionic and / or cationic surfactants prevents the formation of cohesive deposits on the felt. In particular, the adhesion of the tacky material associated with the regenerated fibers is effectively controlled. Therefore, the present invention is particularly advantageous for papermaking devices which use recycled fibers in substantial proportions ie about 10% or more. Moreover, excellent results are obtained in systems where the recycled material is at least 70% of the fibers, as well as in systems where paper pulp fibers are about 100% derived from the recycled material. The present invention is also particularly advantageous for controlling resin deposits derived from (i.e., at least 5% of) fibers, pines containing substantially at least 2% by weight of resin.

Although the mechanism of this phenomenon has not been fully elucidated, it is known that adhesive materials associated with regenerated fibers are generally hydrophobic, so that the products formed after the interaction of these hydrophobic materials with the cationic component of the present invention are more readily bound to water I think. Thus, the wet adhesive material substantially loses the tendency to stick to the felt surface and can be easily removed from the felt. Paper pulp also contains not only synthetic anionic polymers that may be added as part of the papermaking process, but also naturally occurring anionic polymers, resins, soaps, surfactants, and organic acids associated with anionic debris in this industry (e.g. It is known to contain colloidal substances and anionic polymers. The cationic component added according to the present invention works with the anionic polymer and colloidal particles to form a product that can be easily removed from the felt. In any case, the tendency for the adhesive material to pass through it rather than to adhere to the papermaking device is greatly improved by the treatment according to the invention.

Cationic polymers and surfactants of the invention are added directly in the form of an aqueous solution to the device to be treated. Treatment with surfactants alone is less than the degree of deposit control that can be obtained with the combinations of the present invention. On the other hand, repeated addition of the polymer to the paper mill felt without sufficient surfactant will result in the formation of deposits originating from the polymer itself, which may eventually impede water removal or affect production (e.g. due to increased stickiness). Reduces porosity. Thus the polymer and surfactant throughputs must be adjusted to the needs of the particular system to be treated. Preferably, the aqueous solution containing the cationic polymer and the surfactant should be substantially free of anionic polymer. These anionic substances include natural substances such as wood lignin, by-products of chemical pulping such as sodium lignosulfonate, synthetic substances such as polyacrylates, and the like.

The polymers and surfactants of the present invention are typically supplied in a liquid composition comprising an aqueous polymer solution and / or surfactant. The polymer concentration in the composition can range from a relatively dilute solution having a concentration suitable for continuous addition to the limit of dissolution or gelation of the polymer, but in general the composition is relatively concentrated for actual shipping and handling purposes. Indeed the liquid composition may comprise additional substances which dissolve the polymer to allow for a more concentrated composition. Examples of these materials are alkoxyethanols such as butoxyethanol. Aqueous compositions suitable for shipping and handling generally contain 5-50% by weight of the active cationic polymer of the present invention. Cationic surfactants of the present invention are provided as a separate composition from the polymer composition and are added separately to the felt (e.g., by separate shower systems) or mixed before addition, and include cationic polymers as well as cationic surfactants. It is desirable to provide an aqueous composition. Other materials may also be present in the compositions of the present invention, but useful compositions may be prepared according to the present invention that contain a pitch control agent consisting essentially of the cationic surfactant and cationic polymer described above. Generally aqueous compositions suitable for shipping and handling contain 5-50% by weight of the total polymer and surfactant components. The weight ratio of surfactant to polymer is generally about 50: 1 to 1:50. Preferably the weight ratio of surfactant to polymer in the aqueous composition is from about 10: 1 to about 1: 1, in particular oil may be present, and most preferably about 1: 1 for general application, although oil is present In such cases, an excess of surfactant (weight ratio of at least 1.1: 1) may be considered to be most suitable.

One aqueous agent which is considered to be particularly suitable for the addition of the polymer component together with the further addition of the surfactant is commercially available from Divon Chemical Company Limited, Ontario, Canada and also has a formaldehyde, ammonium chloride, dish having a molecular weight of about 20,000 to 50,000. About 17% by weight of the active polymeric condensation product of andamide and formic acid, about 2% by weight of the active polymer obtained by reacting epichlorohydrin with dimethylamine having a molecular weight of about 20,000 to 30,000, and about 8% by weight of butoxyethanol do. Small amounts of other materials, including about 0.4% of the active alkyl dimethyl ammonium chloride surfactant containing a mixture of the aforementioned C ₁₂ , C ₁₄ and C ₁₆ n-alkyl substituents, may also be present in this product, It is not essential. In particular, the relative amounts of alkyldimethyl ammonium chloride surfactants in this product are insufficient to activate the polymer deposition inhibiting effect of the present invention. Other aqueous agents particularly suited for the separate addition of polymers are commercially available from Dearborn Chemical Company Limited and comprise about 17% by weight of active poly (hydroxy alkylene dimethyl ammonium chloride) having a molecular weight of about 20,000. Particularly suitable aqueous agents for the separate addition of surfactants according to the invention are commercially available from Dearborn Chemical Company Limited and comprise about 16% of the above-mentioned active alkyldimethyl benzyl ammonium chloride surfactant mixtures.

The most suitable throughput depends on factors such as the nature of the adhesive material and whether the cleaning is continuous or periodic. Liquid compositions comprising relatively high concentrations (eg 50%) of the polymers of the invention can be applied at full strength (100% as liquid composition) by spraying the undiluted liquid composition directly onto the felt. However, it is advantageous that the composition is diluted with purified or other aqueous liquids at the treatment site, especially when the continuous treatment is carried out. Good quality chemical water is suitable for dilution if needed for water economy.

The advantages of the present invention can be realized in surfactants that are sufficient to inhibit polymer addition concentrations as low as 2 ppm where continuous treatment is performed and formation of deposits derived from added cationic polymer components as shown below. Continuous treatment of the felt as used herein means that the felt is processed periodically one or more times while the felt is circulated between the sheet contacting step and its conveying step. This periodic processing is preferably applied during the initial part of the conveying step. The felt is contacted with the sheet so that the sticky material, including the sticky material associated with the regenerated fibers, is prevented from adhering to the felt and the aqueous wash solution is added during the conveying step so that non-deposited material is more easily removed. In some cases continuous treatment is not substantial and treatment with cationic polymers and surfactants of the present invention may be periodic. For example, aqueous solutions of polymers and surfactants are sprayed onto the felt until the felt is sufficiently conditioned, and the spray is discontinuous until supplemental control is needed to inhibit deposit formation on the felt.

The treatment process is described in more detail with reference to the typical papermaking felt device shown briefly in FIGS. The compression felt device, generally indicated at 10 in FIG. 1, includes an upper compression felt 12, a lower compression felt 14, a final compression lower felt 16 and a final compression upper felt 18. The final compressed lower felt 16 is wound around a series of rolls 20, 21, 22, 23, 24, 25 and 26 and the compression roll 29, Compression felt 14 is wound around a series of rolls 30, 31, 32, 33, 34, 35 and 36 and compression rolls 37 and 38. The upper compression felt 12 is wound around a series of rolls 40, 41, 42, 43, 44 and 45 and the compression roll 47, and the final compressed upper felt Is wound around the compression roll 49 and the series of rolls 60, 61, 62 and 63. Upper compression felt 12 and lower compression felt 14 pass between compression rolls 37 and 47. The lower compression felt 14 passes between the rolls 38 and 48, and the final lower compression felt 16 and the final compression upper felt 18 pass between the compression rolls 29 and 49. . Wash showers for the upper compression felt 12, the lower compression felt 14, the final compression lower felt 16 and the final compression upper felt 18 are respectively 50, 51, 52 and 53. Is shown. Sheet support rolls are shown at 55. Compressor 57 includes compression rolls 37 and 47. Compressor 58 includes compression rolls 38 and 48. In addition, the compressor 59 includes compression rolls 29 and 49.

Compression felt device 10 is shown in FIG. 1 to receive sheet material from a Fourdrinier wiring machine, which is shown in part 64 in FIG. 1, where wire 65 is a head box. It is designed to accommodate aqueous paper stock from (not shown). During the wire sheet contacting step, the liquid is generally squeezed through the pores in the wire as it moves into the mass grinding roll 66 and the couch roll 67 to compress the sheet material and separate it from the wire 65. . The wire passes through the head roll 68 and is then conveyed to receive additional paper stock. The conveyance is typically performed via a series of showers (not shown) and washing rolls such as shown by 69. Other showers (not shown) may be provided for certain components of the device, such as agglomerated grinding rolls 66 or head rolls 68.

While the felt device shown in FIG. 1 is in operation, the sheet material is removed from the wire 65 after the couch roll 67 is directed between the rolls 45 and 36 and the upper compression felt 12 and the lower compression felt. Compressed by the compression rolls 37 and 47 of the compressor 57 between 14. This sheet material moves along the lower compression felt 14 to the compressor 58, where the sheet material is compressed between the lower compression felt and the compression roll 48 using a compression roll 38. This sheet material is then removed from the lower compression felt 14 and transferred to the compressor 59 where the compression roll 29 of the compressor 59 between the final compressed lower felt 16 and the final compressed upper felt 18. And 49. The sheet material leaves the final compression felt 16 and passes through a support roll 55 to a processing device such as a dryer (not shown). In the compression felt device 10 as shown in FIG. 1, the sheet contacting step of the upper compression felt 12 is performed by the roll 57 or at some point between the roll 45 and the compressor 57. It continues to some point in the back. The sheet contacting step of the lower compression felt 14 continues from some point between the roll 46 and the compressor 57 to some point after the compressor 58. The sheet contacting step of the final compressed lower felt 16 continues from the roll 36 to some point after the compressor 59. The sheet contacting step of the final compressed upper felt 18 also continues from some point between the roll 63 and the compressor 59 to some point after the compressor 59.

It is clear that additional devices such as various compressors, rolls, showers, guides, vacuum devices and tensioning devices may be included in the felt device 10. Compressors for compressing moisture from the felt may also be provided. Also, some of the devices shown, such as compressor 58 and final compressed top felt 18, may be omitted from the felt device. It is known to those skilled in the art that the felt device varies widely depending on the number of felts used and the design of the felt circulator.

Felt devices can be used in combination with papermaking processes that do not use a Fourdrinier wire former. One particularly useful alternative to producing heavier sheet materials uses bat forming machines. The initial stage of the bat forming apparatus is shown generally in FIG. The apparatus 70 is a series of wire cylinders (i.e. bats) as indicated by (72) and (73) which rotate to adhere the cylinder portion to the pulp slurry and to deposit the paper web layer onto the lower couch felt 75. ). In addition to the lower couch felt 75, the device 70 includes a first upper couch felt 76 and a second upper couch felt 77. Couch rolls 78 and 79 are provided to assist the sheet material from moving from bats 72 and 73 to the lower couch felt 75, respectively. The lower couch felt 75 is wound around the couch rolls 78 and 79, the roll 80, the suction drum 81 and the compression rolls 83, 84, 85 and 86. The first upper couch felt is wound around the rolls 88, 89 and 90 and the suction drum couch roll 91, and the second upper couch felt is pressed through the compression rolls 93, 94 and 95. And (96) and rolls (97), (98), (99) and (100). The lower couch felt 75 and the first upper couch felt 76 pass together between the suction drum 81 and the suction drum couch 91 that suck water from the felt and the fibrous web. The lower couch felt 75 and the second upper couch felt 77 are between compression rolls 83 and 93, between compression rolls 84 and 94, between compression rolls 85 and 95, and Passes between compression rolls 86 and 96. Compressor 103 includes compression rolls 83 and 93, compressor 104 includes compression rolls 84 and 94, and compressor 105 includes compression rolls 85 and 95. And compressor 106 includes compression rolls 86 and 96.

Showers for cleaning the lower couch felt 75, the first upper couch felt 76, and the second upper couch felt 77 are shown in 107, 108, and 109, respectively.

During operation of the felt shown in FIG. 2, the sheet material from the batts 72 and 73 is passed through the suction drum to the lower couch felt 75 and between the lower couch felt and the second upper couch felt 77. Compressed by compressors 103, 104, 105, and 106. The sheet material is separated from the couch felts 75 and 77 and sent to another processing device, such as the felt device 10 shown in FIG. In the system shown in FIG. 2, the sheet contacting step of the lower couch felt 75 continues from the bat 72 to just behind the compression roller 86. The contacting step of the first upper couch felt is at the suction drum couch roll, and the sheet contacting step of the second upper couch felt is continued from the roll 100 to just behind the compression roller 96. The system 70 may include additional devices such as bats, compressors, rolls, showers, guides, vacuum devices, and tensioning devices. Also, some of the illustrated apparatus may be omitted in the bat forming apparatus. It is well known to those skilled in the art that the bat forming apparatus can vary widely depending on the number of felts used and the design of the felt circulator.

Each felt 12, 14, 16, 18, 75, 76 and 77 of the device shown in FIGS. 1 and 2 is a suitable cationic polymer and surfactant. The aqueous solution can be treated continuously according to the invention by adding it anywhere in the felt during the conveying step (ie from contact with the sheet material to the point where the felt is contacted again with the sheet material). It is preferred that the solution be sprayed onto the felt at the beginning of the felt conveying step so that the adhesive material transferred from the sheet material to the felt can be processed quickly. However, the treatment location is often limited by the felt device design. Therefore, showers such as those shown in (50), (51), (52), (53), (107), (108) and (109) in FIGS. 1 and 2 can be used for treatment purposes. have. If the added solution is much higher than the concentration required for the continuous treatment, stop the addition and resume as necessary. For example, when showers such as those shown in (50), (51), (52), (53), (107), (108) and (109) are used to add a solution, It can be activated or stopped. Devices other than felt may be similarly treated in a manner consistent with these processes.

Cationic polymers are generally added at about 0.002 g (g / m 2 -min) when using a typical papermaking process, especially significant amounts of regenerated fibers, preferably at least 0.01 g / m 2 -min for continuous processing, and addition Is sometimes at least about 0.02 g / m 2 -minute during addition. In order to minimize the possibility of felt clogging, a polymer addition ratio of preferably 0.5 g / m 2 -min or less is used. At standard initial values of 2 to 7 m felt width and 10 to 40 m felt length, the addition ratio is usually about 0.02 to 20 g of polymer (g / m 2 -min) per minute per meter width, more often about 0.5 to 12.5 g / m 2- Minutes. One method first adds 1 g / m 2 or more until the felt is conditioned. Once conditioning is complete, the sustained polymer addition rate may be lowered or the addition may be stopped periodically as described above. Surfactants are added to the felt at a rate effective to inhibit the formation of deposits derived from the added polymer and are therefore important in controlling felt clogging. Thus the weight ratio of surfactant to polymer is usually maintained between about 50: 1 and 1:50. Preferably the weight ratio of surfactant to polymer is at least about 1: 1 to provide sufficient surfactant to inhibit deposit formation derived from the polymer and to protect it from any amount of debris and oily material from the pulp, and excess In order to avoid the addition of surfactants, the surfactant to polymer weight ratio is preferably about 10: 1 or less. Most preferably the ratio of two components is about 1: 1. In either case, it is desirable to add a surfactant at a concentration of at least about 1 ppm. Other devices such as wires, screens, filters, rolls and suction boxes, and materials such as metals, granite, rubber and ceramics can be advantageously treated according to the present invention. However, the present invention is particularly useful for treating felt and similar device parts having pores suitable for water to enter (ie, relatively micropores) in which formation of substantial deposits derived from polymers is undesirable. This is in contrast to other devices such as metal and plastic wires with relatively large pores that can drain through them, where formation of certain amounts of deposit does not create undesirable problems.

In any case, the concentration of cationic polymer in the aqueous solution added to the felt or other papermaking apparatus should be at least about 0.0002% by weight. In order to improve the uniformity of the distribution of the polymer, the continuous treatment of the felt through the felt shower according to the invention is carried out with an aqueous shower solution having from about 0.0002% by weight to about 0.02% by weight cationic polymer.

The practice of the present invention may be further detailed from the following non-limiting examples.

Example 1

The test of this example was carried out on a paper machine having a Fourdrinier wire former. This paper machine has an upper first felt felt, lower part somewhat similar to the upper compressed felt 12, the lower compressed felt 14, the final compressed upper felt 18 and the final compressed lower felt 16 shown in FIG. It has a 1st compression felt, an upper 2nd compression felt, and a lower 2nd compression felt. Each felt has a shower. The first compression felt accepts sheet material from a podlinear wire positioned somewhat similar to the device 64 shown in FIG. 1, so that about 20% of secondary (regenerated) fibers and about 80% of solid wood A cortex material is produced from paper stock with fibers.

The sheet material formed on the wire is separated therefrom and sent to a first compressor, somewhat similar to the compressor 57 of FIG. 1, to compress the sheet material between the upper first compression felt and the lower first compression felt. This sheet is again separated from the first compression felt and sent to a second compressor, somewhat similar to the compressor 59 in FIG. 1, which is compressed between the upper second compression felt and the lower second compression felt.

Paper machines have been faced with deposit formation on compression felt, especially on top of the second compression felt. This deposit is due to the pitch and sticky material derived from the pulp and recycled material and is obtained from the fibrous web in contact with the felt. Sheet failure in the second compressor has been an ongoing problem, with frequent failures occurring at one frequency per 8 hours of operation. Therefore, periodic shutdowns were necessary to reduce the number of sheet breaks. The upper second compression felt is about 609.6 cm (20 feet) wide and 1874.5 cm (61.5 feet) long (ie, the processing area of the upper second compressor is about 114,3 m 2).

The upper second compression felt is a mixture of alkyldimethyl benzyl ammonium chloride as described above containing C ₁₂ , C ₁₄ and C ₁₆ n-alkyl substituents in the shower water of a high pressure shower, similarly to shower 53 in FIG. 1. About 7.5% by weight and molecular weight about 20,000 and about 7.5% by weight polymer derived from dimethyl amine and epichlorohydrin, and a solvent (this solvent is mainly mixed with ethanol mixed with water and for example commercially available surfactants and / or polymers) The same small amount consists of the material) and is treated according to the invention by mixing with a test product containing about 85% by weight. The initial dose is about 0.06 g / min / m 2 of each component and after 4 hours the dose is reduced to about 0.02 to 0.03 g / min / m 2.

The effectiveness of this treatment is examined by the number of breaks occurring in Huyck Smith's porosity tester and second compressor area. The porosity of the felt can be thought of as a measure of the capacity to absorb water from the sheet. High porosity felts (ie, more open pores) may be considered desirable for sheet dewatering.

During 21 days of work using the Huyck Smith method, which provides relative porosity numbers (H, S numbers) ranging from up to 100% for non-porous or clogged felt to lower percentages for more porous felt. Examine the relative porosity of the upper second compression felt. The H. S number for the upper second compression felt is maintained at about 35% during the first few days of the test. The supply of the treated product is optionally stopped over 24 hours. An increase in the number of H. S is observed by about 50%, due to treatment interruption. Wash the felt and resume the test. After resuming treatment, the H. S number is reduced to about 45% and lasts for several days. Due to pump dysfunction, the dose of each treatment component is reduced by about half and the H. S number is increased by 53%. At the original dose, the H. S number lasts about 53% during the test.

Porosity measurements performed during the test indicate that the porosity of the felt can be maintained with the addition of polymers and surfactants in accordance with the present invention. If the supply is stopped, felt clogging is increased by about 15-40%. In addition, sheet failure by the upper second compression felt is also eliminated during the entire 30 day test period. Thus, the treatment according to the invention can prevent breakage and shutdown due to deposits in the second compressor, prevent adhesive deposits on the treated felt and significantly reduce felt clogging by fibers during the treatment. You can see that you can.

Example 2

The test of this example is carried out on a bat secondary mold machine (rather than a ford linear type) paper machine. This paper machine is similar to the lower lower couch felt 75, the upper upper couch felt 76 and the upper upper couch felt 77 shown in FIG. Have a felt. This paper machine also has a second upper felt, a second lower felt and a final felt somewhat similar to the upper compressed felt 12, the lower compressed felt 14 and the final compressed lower felt 16 shown in FIG. (Ie no felt similar to the final compressed upper felt 18). Each felt has a wash shower. The paper machine has seven wire cylinders (i.e. bats) located in series similar to the two bats 72 and 73 shown in FIG. 2, and also made of cardboard (e.g., yellow paper, tubes) from 100% recycled paper stock. Stock, chipboard or chipboard bulkhead).

The paper web formed on the cylinder is separated from the cylinder and bonded to the ground of the primary lower felt. The sheet on the primary lower felt is compressed between the primary lower felt and the suction drum couch felt and then passed about four other compressors between the primary lower felt and the primary upper felt. This sheet is separated from the primary lower felt and sent to a secondary compressor somewhat similar to the compressor 57 shown in FIG. 1 to compress between the secondary upper felt and the secondary lower felt. The sheet is separated from the secondary compression felt and then sent to the final felt to be recompressed using the upper compression roll without the felt in a compressor somewhat similar to the compressor 59 in FIG.

Prior to testing the combination of the cationic polymer and cationic surfactant of the present invention, the primary lower felt, suction drum couch felt, primary upper felt and secondary upper felt in the conventional manner are shown in FIGS. Containing a mixture of C ₁₂ , C ₁₄ and C ₁₆ n-alkyl substituents as described above using a shower positioned somewhat similar to the showers 107, 108, 109 and 50 shown. Pretreat with alkyldimethylbenzyl ammonium chloride product. Test product containing about 7.5% by weight alkyldimethyl benzylammonium chloride mixture, about 20,000 molecular weight and 7.5% by weight polymer derived from dimethylamine and epichlorohydrin, and about 85% solvent (i.e. Example 1 The same product as used in) is diluted with shower water to a concentration of about 2.6 ppm of surfactant and polymer and added to the same four felts. After the initial addition, the addition of the polymer during the period showed no blockage of the felt, followed by a 50% increase in the concentration of surfactant and polymer (level of about 4 ppm). Processing continues at this level as the remainder of the testing process. Each component is added to the felt at a rate of about 1.5 g / min during the beginning of the test and at a rate of about 2.25 g / min for the remainder of the test period. The primary lower felt, suction drum couch felt, primary upper felt and secondary upper felt are all about 236.2 cm (7.75 feet) wide and about 3169.9 cm (104 feet) long and 1889.7 cm (62 feet) respectively. ), 2011, 6 cm (66 feet) and 1280.1 cm (42 feet) (ie, the treatment areas are about 74.9 m 2, 44.7 m 2, 47.5 m 2 and 30.3 m 2, respectively).

The relative porosity (eg inch Hg), measured in vacuum during the test, is adjusted for the width of the untreated secondary lower felt as well as the width of the treated felt. Substantial increase in the degree of vacuum means deterioration of the felt. The results are shown in Tables I to V below.

It can be clearly seen from Tables I to V above that cationic polymers can be added to paper machine felt according to the invention without clogging the felt and without destroying the porosity of the felt. The pressure load (i.e. the pressure loaded by the compression rollers of the six compressors in the paper machine) does not change throughout the test period, and also the primary lower felt, suction drum couch felt, primary upper felt, secondary upper felt and secondary lower felt The vacuum pressure measured at the 13 points between the felts (ie the suction pressure applied to remove the liquid from the felt) also remained unchanged for the entire test period. The couch vacuum degree does not change during the test period. Several sheet characteristics during the test period are observed and summarized in Table VI below.

The pH of the paper stock is maintained at about 6 and the bat temperature is about 38 ° C. The consistency of the paper stock is about 0.37% for the cylinders 1 and 6 and about 0.40 for the cylinders 2, 3, 4, 5 and 6 %to be. Paper quality remains unchanged during the test. The optimum moisture content is about 5% and the optimum caliper is about 800.

It is clear from Table VI that the desired sheet moisture content can be maintained during the treatment and also high rates can be maintained during and after felt conditioning according to the invention.

Example 3

The test of this embodiment is run on a paper machine having a single wire pod linear with a series of compressors and felts connected to a pick-up felt and a yankee drier. Paper machines typically process paper stocks having a substantial proportion (ie between about 40 to 100%) of de-inked recycled pulp. Paper stock is typically maintained at pH 6.0-6.5 and a temperature of about 40 ° C., and paper machine production is about 50 tons per day.

Prior to testing, the felt is washed up to 15 times a day with an organic solvent and / or a mixture of organic solvent and cleaning agent. Approximately 5 gallons of solvent are used per wash (ie, less than about 75 gallons of solvent per day), and solvent washes are performed on-the-fly as described in Sheet Quality. Due to poor sheet quality, a significant amount of paper cannot be sold. De-ink regenerated pulp, which is relatively inexpensive and where high rates are desirable, causes running problems during processing steps that can lead to sheet inertia and / or failure. The proportion of deink pulp that can actually be used is typically limited to up to about 60%.

Before testing, install a new pick-up felt about 2.7 m wide and 16.2 m long. Two lubricant showers are provided for this pick-up felt. This type of felt has a shelf life of about 50 days. For this test, install a new low pressure fan shower on a sheet surface of approximately 91.4 cm (3 feet) of felt in front of the suction box. These showers use fresh water and 2U each minute. There are 13 nozzles in the S gallon.

In this test, a test article containing about 7.5% by weight alkyldimethyl benzyl ammonium chloride mixture, about 20,000 molecular weight and about 7.5% polymer derived from dimethylamine and epichlorohydrin, and about 85% solvent (ie, Examples) The same product as used in 1 and 2) is diluted with fresh shower water in a new low pressure shower to a concentration of about 34 ppm of surfactant and polymer, respectively, and the surfactant and polymer are added to the felt at a rate of about 0.09 g / m 2 -min.

If the felt porosity is not adjusted in this paper machine, it is evident that the frequency of solvent washing for the felt can be reduced within a few hours of the start of the test. Therefore, the deink pulp content in paper stock is increased to 100%. The frequency of solvent washes is reduced by 5 to 12 washes per day for 5 days, and the amount of solvent required per wash is reduced to about 3 gallons per wash, which can reduce the amount of solvent used per day to about half (ie about Up to 36 gallons).

Reposition the low pressure shower in a new location behind the suction box. The frequency of solvent washes is reduced about three times a day. The new shower location therefore means an improvement.

The paper stock content is changed to 60% deink pulp / 40% unused stock. This grade reduces the frequency of solvent washes to about once a day.

In summary, even in a preliminary test lasting about 18 days, the treatment of the felt in the machine according to the invention described herein allows the use of raw materials with high de-ink pulp content without causing poor runability problems and is necessary for effective production. It can be seen that significant cost savings can be provided by reducing the volume of solvent used for washing and washing, and also reducing the amount of rejects in the finished paper.

The above examples illustrate various embodiments of the invention. Other embodiments will be apparent to those skilled in the art by considering the specification and method of implementation described herein. Modifications and variations are feasible without departing from the spirit and scope of the invention. In addition, the present invention is not limited to the specific combinations and examples, and includes modifications thereof as long as they fall within the claims of the present invention.

Claims (45)

(a) adding an aqueous solution containing 0.0002 to 0.2% by weight of cationic polymer to the paper machine felt device part, and (b) containing the compound selected from the group consisting of water-soluble nonionic and cationic surfactants. Adding an aqueous solution to the felt in a weight ratio of 50: 1 to 1:50 of surfactant to polymer to inhibit deposit formation derived from the cationic polymer. A method of inhibiting deposit formation of tacky material on device components. The process of claim 1 wherein the cationic polymer is a dicyandiamide-formaldehyde condensation polymer comprising a compound selected from the group consisting of formic acid and ammonium salts as polymerization reactants. The method of claim 2, wherein the cationic polymer is derived from the reaction between formaldehyde, dicyanidiamide, formic acid, and ammonium chloride. The process of claim 1 wherein the cationic polymer is obtained by reaction between epihalohydrin and an amine or is derived from ethylenically unsaturated monomers containing quaternary ammonium groups. The method of claim 1 wherein the cationic polymer produces a proton or contains quaternary ammonium groups. The method of claim 1 wherein the cationic polymer is derived by reacting epihalohydrin with a compound selected from the group consisting of diethylamine, dimethylamine and methylethylamine. The method of claim 6, wherein the cationic polymer is prepared by reacting epichlorohydrin with dimethylamine. The method of claim 6, wherein the cationic polymer is prepared by reacting epichlorohydrin with diethylamine. Paper machine circulating between the sheet contacting step and the conveying step according to claim 1, wherein the surfactant and cationic polymer are added to the paper machine felt in the same aqueous solution with a surfactant to polymer weight ratio of 50: 1 to 1:50 during the conveying step of the felt. How to control material deposition on felt. The method of claim 9 wherein the aqueous solution is an aqueous solution free of anionic polymers. The method of claim 10, wherein the cationic polymer is added at a rate of 0.002 to 20 g / m 2 -min. 10. The method of claim 9 wherein the deposit is controlled on a felt containing sheet material from the bat of the bat forming machine. 10. The method of claim 9, wherein the deposit is controlled on a felt that receives the sheet material from the wire of the pod linear wire former. The method of claim 9, wherein the felt is continuously treated with an aqueous solution. The method of claim 14, wherein the cationic polymer is added at a ratio of 0.01 to 20 g / m 2 -minute. The method of claim 9 wherein the felting treatment with the aqueous solution is occasionally stopped. The method of claim 16 wherein the cationic polymer is added at a rate of 0.02 to 20 g / m 2 -min during the addition period. The method of claim 1 wherein 10-100% of the paper machine pulp fibers are derived from recycled material. The method of claim 1 wherein the paper machine pulp fibers are 100% derived from the recycled material. The process of claim 1 wherein the paper machine pulp slurry is derived from pine tree containing at least 2% by weight resin. The method of claim 1 wherein the aqueous solution containing the surfactant contains at least 1 ppm of surfactant. The method of claim 1 wherein the added surfactant is selected from surfactants having a molecular weight of 200 to 800 and having the general formula:

Wherein R is independently selected from the group consisting of hydrogen, polyethylene oxide group, polypropylene oxide group, alkyl group having 1 to 22 carbon atoms, aryl group and aralkyl, at least one R group having 8 to 16 carbon atoms X 'is an anion or n / is 1 / n of an anion. 23. The method of claim 22, wherein the two to four R groups of the surfactant are n-alkyl groups having 12 to 16 carbon atoms. The method of claim 23, wherein two R groups of the surfactant are selected from methyl and ethyl and one R group

And

Method selected from. The method of claim 23, wherein the surfactant is an alkyl dimethyl ammonium chloride or a mixture of alkyldimethyl ammonium chlorides. (Iii) at least 2 PPM of cationic polymer having a molecular weight of 10,000 to 300,000, and (ii) an aqueous solution containing a water-soluble surfactant having a molecular weight of 200 to 800 and having the following general formula, inhibiting the formation of deposits derived from cationic polymers. Added to the felt during the conveying step in a weight ratio of surfactant to polymer of 50: 1 to 1:50, and 0.002 to 0.5 g / so that the cationic polymer and the surfactant are combined with the hydrophobic material to lose adhesion to the felt. Used to process the pulp slurry into a sheet, circulating between the sheet bonding step and the conveying step to inhibit deposit formation of the tacky hydrophobic material on the felt, comprising adding the cationic polymer at a ratio of minute / felt m 2. How to deal with a paperless felt,

Wherein R is independently selected from the group consisting of hydrogen, polyethylene oxide group, polypropylene oxide group, alkyl group having 1 to 22 carbon atoms, aryl group and aralkyl, at least one R group having 8 to 16 carbon atoms X 'is an anion or n / is 1 / n of an anion. 27. The method according to claim 26, wherein the papermaking felt is used in a system wherein the recycled fibers are selected from systems wherein 10 to 100% of the fibers in the system and at least 5% of the fibers are derived from pine trees containing at least 2% by weight resin. . 27. The process of claim 26, wherein the felt is typically treated one or more times during cycling between the sheet contacting step and the conveying step, and the cationic polymer is added at a rate of 0.02 to 0.5 g / m 2 -min. 27. The method of claim 26, wherein the aqueous solution is sprayed onto the felt at a rate of 0.02 to 0.5 g cationic polymer / m < 2 > -min until conditioning is achieved, and until further conditioning is required to inhibit deposit formation on the felt. How to stop spraying. During the conveying step, the felt was contacted with an aqueous solution containing no anionic polymer and (iii) at least 2 ppm of cationic polymer having a molecular weight of 10,000 to 3,000,000 and (ii) a water-soluble surfactant having a molecular weight of 200 to 800 and having the general formula And surfactants are added with a surfactant to polymer weight ratio of 10: 1 to 1: 1 to inhibit the formation of deposits derived from cationic polymers to interact with the anionic polymers and adhesive materials and to easily remove them from the felt. Wherein the recycled fiber is 10 to 100% of the fiber in the papermaking system, including forming a product that can be made, and the felt is circulated between the sheet contacting step and the conveying step and contains anionic polymer and adhesive material. A method of controlling the deposition of adhesive material on paper machine felt in papermaking systems used to process pulp slurry into sheets,

Wherein R is independently selected from the group consisting of hydrogen, polyethylene oxide group, polypropylene oxide group, alkyl group having 1 to 22 carbon atoms, aryl group and aralkyl, at least one R group having 8 to 16 carbon atoms X 'is an anion or n / is 1 / n of an anion. 31. The process of claim 30 wherein the regenerated fibers are 70-100% of the fibers in the papermaking system and the cationic polymer is added at a rate of 0.02-20 g / m 2. (a) cationic polymer, and (b) water-soluble surfactant having a molecular weight of 200 to 800 and having the general formula Compositions for controlling deposition,

Wherein R is independently selected from the group consisting of hydrogen, polyethylene oxide group, polypropylene oxide group, alkyl group having 1 to 22 carbon atoms, aryl group and aralkyl, at least one R group having 8 to 16 carbon atoms X 'is an anion or n / is 1 / n of an anion. 33. The composition of claim 32, wherein the cationic polymer has a molecular weight between 10,000 and 3,000,000. 34. The composition of claim 33, wherein the cationic polymer is a dicyandiamide-formaldehyde condensation polymer comprising a compound selected from the group consisting of formic acid and ammonium salts as polymerization. 34. The composition of claim 33, wherein the cationic polymer is derived from the reaction between formaldehyde, dicyanidiamide, formic acid, and ammonium chloride. 34. The composition of claim 33, wherein the cationic polymer is obtained from the reaction of epihalohydrin with an amine or derived from ethylenically unsaturated monomers containing quaternary ammonium groups. 34. The composition of claim 33, wherein the cationic polymer has a molecular weight of 2,000 to 300,000 and protons or contains quaternary ammonium groups. 34. The composition of claim 33, wherein the cationic polymer is derived by reacting epihalohydrin with a compound selected from the group consisting of diethylamine, dimethylamine, and methylethylamine. 34. The composition of claim 33, wherein two to four R groups of the surfactant are n-alkyl groups having from 12 to 16 carbon atoms. 40. The compound of claim 39 wherein two of the R groups of the surfactant are selected from methyl and ethyl, and one R group

And

Composition selected from. 40. The composition of claim 39, wherein the surfactant is an alkyldimethyl ammonium chloride or alkyldimethyl ammonium chloride mixture. The composition of claim 41 wherein the cationic polymer is derived from dimethylamine and epichlorohydrin and has a molecular weight of 20,000. 34. The composition of claim 33 which is an aqueous solution containing from 5 to 50% by weight of the polymer and surfactant. The composition of claim 33, wherein the weight ratio of surfactant to cationic polymer is from 10: 1 to 1: 1. 45. The composition of claim 44, wherein the weight ratio of surfactant to cationic polymer is from 10: 1 to 1.1: 1.

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