WO2023122637A1 - Procédé de régulation de la teneur en acides gras volatils dans une pâte à papier - Google Patents

Procédé de régulation de la teneur en acides gras volatils dans une pâte à papier Download PDF

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Publication number
WO2023122637A1
WO2023122637A1 PCT/US2022/082097 US2022082097W WO2023122637A1 WO 2023122637 A1 WO2023122637 A1 WO 2023122637A1 US 2022082097 W US2022082097 W US 2022082097W WO 2023122637 A1 WO2023122637 A1 WO 2023122637A1
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WIPO (PCT)
Prior art keywords
vfa
control agent
process flow
acid
biocidal
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PCT/US2022/082097
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English (en)
Inventor
Corinne E. Carrido
Sachin Borkar
William S. Carey
Original Assignee
Solenis Technologies Cayman, L.P.
Solenis Technologies, L.P.
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Application filed by Solenis Technologies Cayman, L.P., Solenis Technologies, L.P. filed Critical Solenis Technologies Cayman, L.P.
Publication of WO2023122637A1 publication Critical patent/WO2023122637A1/fr

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Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
    • D21H21/36—Biocidal agents, e.g. fungicidal, bactericidal, insecticidal agents
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
    • D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
    • D21C9/08—Removal of fats, resins, pitch or waxes; Chemical or physical purification, i.e. refining, of crude cellulose by removing non-cellulosic contaminants, optionally combined with bleaching
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H13/00—Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material
    • D21H13/10—Organic non-cellulose fibres
    • D21H13/28—Organic non-cellulose fibres from natural polymers
    • D21H13/30—Non-cellulose polysaccharides
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H17/00—Non-fibrous material added to the pulp, characterised by its constitution; Paper-impregnating material characterised by its constitution
    • D21H17/03—Non-macromolecular organic compounds
    • D21H17/05—Non-macromolecular organic compounds containing elements other than carbon and hydrogen only
    • D21H17/09—Sulfur-containing compounds
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/02—Agents for preventing deposition on the paper mill equipment, e.g. pitch or slime control
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/02—Agents for preventing deposition on the paper mill equipment, e.g. pitch or slime control
    • D21H21/04—Slime-control agents
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/06—Paper forming aids
    • D21H21/12—Defoamers
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
    • D21H21/16—Sizing or water-repelling agents
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21H—PULP COMPOSITIONS; PREPARATION THEREOF NOT COVERED BY SUBCLASSES D21C OR D21D; IMPREGNATING OR COATING OF PAPER; TREATMENT OF FINISHED PAPER NOT COVERED BY CLASS B31 OR SUBCLASS D21G; PAPER NOT OTHERWISE PROVIDED FOR
    • D21H21/00—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties
    • D21H21/14—Non-fibrous material added to the pulp, characterised by its function, form or properties; Paper-impregnating or coating material, characterised by its function, form or properties characterised by function or properties in or on the paper
    • D21H21/22—Agents rendering paper porous, absorbent or bulky
    • D21H21/24—Surfactants

Definitions

  • the present disclosure relates generally to pulp, paper, and/or board making processes and, more specifically, to methods of controlling contamination and odor associated with microbial starch degradation and fatty acid production.
  • Papermaking is a complex process in which paper is prepared from pulp (e.g. wood), water, filler, and various chemicals. Paper manufacturing is also among the most water intensive industries, with numerous stages reliant on substantial amounts of water and aqueous solutions being added to the cellulosic fibers (i.e., the “inflow stream”), and eventually separated therefrom (i.e., the “effluent stream”).
  • a relatively concentrated aqueous slurry of cellulosic material i.e., “thick stock”
  • a relatively diluted slurry of cellulosic material i.e., “thick stock”
  • the so-called “thin stock” which is used to prepare a paper web from which the water must be separated to give the final product.
  • the waste water (i.e., white water) volumes are thus quite high, necessitating reuse of water for both economical and environmental benefits.
  • typical paper mills employ increasingly closed water systems in order to maximize water reuse and abide environmental regulations.
  • recycled fiber material which is commonly used as raw material for paper or board, typically comprises starch that originates from the surface sizing of the paper or board. This starch is generally of low molecular weight and little to no ionic charge, and thus may not be retained on the fibers or effectively separated during screening, leading to increasing loads within closed water circulation systems.
  • VFA volatile fatty acids
  • a method of controlling volatile fatty acid (VFA) content in a pulp, paper, and/or board making processes includes treating a process flow comprising a cellulosic material comprising a starch with a VFA control agent.
  • the VFA control agent is non-biocidal, and utilized in an amount sufficient to inhibit microbiological production of one or more VFA.
  • the method optionally includes treating the process flow with a biocidal agent.
  • the VFA control agent comprises a surfactant or dispersant, a chelator or sequestrant, or a combination thereof, capable of inhibiting amylase activity in the process flow.
  • a method of controlling volatile fatty acid (VFA) content in pulp, paper, and/or board making processes is provided.
  • the method provides for an efficient and effective solution useful for controlling microbial-related starch degradation and odor in both the process stream as well as product being prepared.
  • the method may be used to increase the starch content available with recycled fibers, improve runnability, optimize retention, and increase strength properties associated with the process being utilized.
  • the method comprises treating a process flow comprising a cellulosic material comprising a starch with a non-biocidal VFA control agent in an amount sufficient to inhibit microbiological production of one or more VFAs.
  • the process flow is not limited, and is to be understood to generally include any aqueous solution, suspension, or dispersion comprising cellulosic material (e.g. in the form of fibers, fines, etc.) used in a pulp, paper, and/or board making processes.
  • the process flow comprises recycled fiber material, e.g. from recycled paper, recycled board, etc., which comprise fibers and starch.
  • recycled fiber material may include broke originating from rejected materials from a paper or board.
  • the process flow may thus be a pulp flow, a think stock, a thick stock, a furnish, etc.
  • the process flow being treated involves a pulping step, e.g.
  • treating the process flow comprises combining the VFA control agent with water in a papermaking process or system, alternatively with water that is subsequently utilized in a papermaking process or system.
  • the water is not limited, and may be river water, municipal water, waste water (e.g. white water), recycled water, etc., or any other water source that may be typically used, as would be understood by those of skill in the art.
  • cellulosic material refers to any material comprising cellulose, including recovered (e.g. waste) paper.
  • cellulosic material includes all intermediate and final products during the paper making process, including dispersions or suspensions of cellulosic material, pulped cellulosic material, de-inked cellulosic material, blended cellulosic material, bleached cellulosic material, refined cellulosic material, screened cellulosic material, as well as the final paper, paperboard or cardboard prepared therefrom.
  • pulp, slurry, sludge, and stock may be considered cellulosic material.
  • the cellulosic material may contain further components besides cellulose and starch, such as chemicals used for pulping steps, dyes, bleaching agents, fillers, processing aids, etc.
  • starch is used in the conventional sense to refer to a polysaccharide carbohydrate comprising glucose units joined together via glycosidic bonds.
  • the starch may be modified or non-modified, including any starch typically employed in paper manufacture.
  • the starch may be native or added to the cellulosic material.
  • the cellulosic material comprising the starch may be from waste paper or broke, may be blended with virgin material, or may be prepared from pure virgin material by added starch thereto (e.g. from a recirculation unit supplying the pulper with recycle water, such as from the wet end of a papermaking machine).
  • VFA volatile fatty acids
  • fatty acids e.g. based on linear or branched carbon chains having one to seven carbon atoms (i.e., Cl to C7), optionally substituted with a carboxyl group (i.e., C(O)OH) and/or a hydroxyl group (-OH).
  • VFAs thus include methanoic (formic) acid, ethanoic (acetic) acid, propanoic (propionic) acid, butanoic (butyric) acid, pentanoic (valeric) acid, hexanoic (caproic) acid, heptanoic (enanthic) acid, as well as variants, salts, and esters thereof.
  • branched variants of butanoic acid include iso-butyric acid, n-butyric acid, and butyric lactic acid.
  • microbes present in the process flow system produce amylases, which are enzymes capable of hydrolyzing starch into the simpler sugar constituents.
  • microbiological production refers to the enzymatic conversion process of starch into sugars, and sugars into VFAs, as facilitated by enzymes produced by microbes.
  • the term “microbial production” is not necessarily limited to an occurrence within a microbe itself, but rather may occur extracellularly via free enzymes.
  • the method includes treating the process flow with a VFA control agent.
  • the VFA control agent is a substance capable of inhibiting the microbial production of VFAs from starch. More specifically, the VFA control agent is non-biocidal, in that it does not possess or exhibit activity to destroy a given microbe, i.e., is not a biocide. It will be appreciated that the VFA control agent may exhibit isolated biocidal activity under certain conditions, such as when present with a microbe in gross-excess concentrations, extreme temperatures, etc.
  • non-biocidal is used to describe a compound or composition that exhibits little or no biocidal activity under the conditions relevant to a papermaking process as described herein, as will be appreciated by those of skill in the art.
  • the VFA control agent comprises a surfactant, a dispersant, a chelator, a sequestrant, or a combination thereof.
  • the VFA control agent may be a single component or compound, or instead be a composition comprising at least one component or compound.
  • the VFA control agent may be, include, consist essentially of, or consist of, the surfactant, dispersant, chelator, sequestrant, or combination thereof, as described herein.
  • the terminology “consist essentially of’ may describe embodiments that are free of, or that include less than 5, 4, 3, 2, 1, 0.5, 0.1, 0.05, or 0.01, weight percent other actives based on a total weight of the VFA control agent, aside from those actives and optional components expressly described. In various non-limiting embodiments, all values and ranges of values including and between those set forth above are hereby expressly contemplated for use herein.
  • the VFA control agent comprises the chelator or sequestrant.
  • the VFA control agent may comprise the chelator or sequestrant based on functionality suitable for binding or bonding to a metal cation, e.g. such as an anionic functional group and/or a functional group with free lone pairs of elections.
  • chelator is uses to refer to compounds capable of binding/bonding to one metal center (e.g. a monovalent metal center), whereas the term “sequestrant” refers to compounds capable of binding/bonding to multiple metal centers and/or form chelate complexes with polyvalent metal ions (e.g. copper, iron, nickel, etc.).
  • polyvalent metal ions e.g. copper, iron, nickel, etc.
  • the collective term “chelator or sequestrant” may refer to a single compound possessing both activities, or to a given compound with only chelating activity, etc.
  • a chelator or sequestrant VFA control agent is a polydentate ligand capable of binding one or more metal atoms, and may be referred to as “chelants”, “chelators”, “chelating agents”, and/or “sequestering agents” by those of skill in the art.
  • VFA control agent examples include phosphonates, acids or salts thereof, phosphates, and derivatives or combinations thereof.
  • the VFA control agent comprises an organic or inorganic phosphonate, a phosphonic acid or salt thereof, or a combination thereof.
  • the VFA control agent comprises an amino phosphonic acid or a salt thereof, a sodium or potassium phosphate, or combinations thereof.
  • the VFA control agent comprises a polyamino polyether methylene phosphonic acid (i.e., PAPEMP), a bis(hexamethylenetriaminepenta(methylene phosphonic acid)) (i.e., BHMTAP), a diethylenetriamine penta(methylene phosphonic acid) (i.e., DTPMP), a sodium hexametaphosphate (SHMP), or the like, or a combination thereof.
  • PAPEMP polyamino polyether methylene phosphonic acid
  • BHMTAP bis(hexamethylenetriaminepenta(methylene phosphonic acid))
  • DTPMP diethylenetriamine penta(methylene phosphonic acid)
  • SHMP sodium hexametaphosphate
  • the VFA control agent may comprise, alternatively may be utilized in conjunction with another component comprising, known chelators and/or sequestrants such as polyamino acids (e.g. ethylenediamine tetraacetic acid (EDTA), diethylenetriamine pentaacetic acid (DTP A), N-(hydroxyethyl) ethylenediamine triacetic acid (HEDTA), propylenediamine tetraacetic acid (PDTA)), other polycarboxylic acids (e.g.
  • polyamino acids e.g. ethylenediamine tetraacetic acid (EDTA), diethylenetriamine pentaacetic acid (DTP A), N-(hydroxyethyl) ethylenediamine triacetic acid (HEDTA), propylenediamine tetraacetic acid (PDTA)
  • EDTA ethylenediamine tetraacetic acid
  • DTP A diethylenetriamine pentaacetic acid
  • HEDTA N-(hydroxyeth
  • NTA nitrilotriacetic acid
  • mellitic acid 1, 2,3,4- cyclopentane tetracarboxylic acid
  • polyacrylic acids e.g. poly(a-hydroxyacrylic acid), poly(tetramethylene- 1 ,2-dicarboxylic acid), poly(4-m ethoxytetramethylene- 1 ,2-dicarboxylic acid), acrylic acid/maleic acid copolymers (polycarboxylate), acrylic acid/allyl alcohol copolymer (polycarboxylate), etc.
  • sodium, potassium, and ammonium salts of phosphonates, phosohonic acids, and salts thereof e.g.
  • the VFA control agent comprises diethylenetriamine penta(methylene diphosphonic acid) (DETPMPA), which may be used in the neutral/acid form or as the sodium salt thereof (i.e., DETPMPA-Na).
  • DETPMPA diethylenetriamine penta(methylene diphosphonic acid)
  • combinations of such chelators and sequestrants may also be utilized, with individual components being selected based on the particular process flow being treated, product being prepared, outcome desired, etc.
  • the VFA control agent comprises the chelator or sequestrant in an amount of from about 10 to about 100, alternatively from about 10 to about 90 wt.% actives, based on a total weight of the VFA control agent.
  • the VFA control agent comprises the chelator or sequestrant in an amount of from about 10 to about 25, about 15 to about 20, about 5 to about 15, about 5 to about 20, about 5 to about 25, about 10 to about 25, about 10 to about 20, about 10 to about 15, about 15 to about 25, about 14 to about 16, about 12 to about 18, or about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30, weight percent actives, based on a total weight of the VFA control agent.
  • all values and ranges of values including and between those set forth above are hereby expressly contemplated for use herein.
  • the VFA control agent comprises the surfactant or dispersant.
  • surfactant and “dispersant” are used herein in the conventional sense, and thus describe overlapping classes of compounds with surfactant or dispersing properties.
  • VFA agents specific examples are provided herein to exemplify surfactants, it is to be appreciated that various dispersant compounds may also be utilized in or as the VFA control agent.
  • surfactant or dispersant VFA control agents inhibit microbial surface adhesion in aqueous systems, prevent biofilm formation and fouling, and disperse bacterial slimes and other such biofilms, and thus reduce VFA formation by generally disrupting microbial systems in the process flow.
  • suitable surfactant-based VFA control agents typically include anionic surfactants such as alkylbenzene sulfonates, which may be linear or branched and generally comprise a benzenesulfonate having a 3 to 20-carbon linear or branched alkyl group substituent (e.g. a dodecyl group).
  • the surfactant may be or include an alkyl aryl sulfonate (such as a linear alkylbenzene sulfonate), an acid thereof, or a combination thereof.
  • the alkyl aryl sulfonate may be any in the art and may be further defined as having any alkyl group such as an ethyl group (e.g. ethyl aryl sulfonate), propyl group (e.g. propyl aryl sulfonate), etc., and combinations thereof.
  • the alkyl aryl sulfonate is a linear alkylbenzene sulfonate.
  • the surfactant is a linear alkylbenzene sulfonate (LAS), an acid thereof, or a combination thereof.
  • linear alkylbenzene sulfonates and acid thereof include those having the structure: wherein each subscript m is independently a number of from 0 to 16, each subscript n is independently a number of from 0 to 16, the sum of m+n is typically number of from 4 to 16, and X is a counter ion.
  • each of the variables designated as subscript m and subscript n may be the same or may be different from each other.
  • each of m and/or n is independently 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16, so long as the sum of m+n is a number of from 4 to 16, e.g. 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16.
  • the counter ion may be any ion that has a +1 charge, such as any organic or inorganic counter ion.
  • the counter ion is Na+ or K+.
  • m+n 8 to 10 and X is Na+.
  • Linear alkylbenzene sulfonates are commercially available from a number of suppliers including Stephan Company of Northfield Illinois, USA., and TCI America of Portland Oregon, USA. It will be appreciated that combinations of two or more independent alkyl aryl sulfonates may also be used in or as the VFA control agent herein.
  • the surfactant comprises, alternatively is, a dodecylbenzene sulfonate, dodecylbenzene sulfonic acid, or a combination thereof.
  • the VFA control agent may comprise the surfactant or dispersant in an amount sufficient to inhibit microbiological production of one or more VFA.
  • the VFA control agent comprises the surfactant or dispersant in an amount of from about 5 to about 30 weight percent (wt.%) actives, based on a total weight of the VFA control agent.
  • the VFA control agent comprises the linear alkylbenzene sulfonate in an amount of from about 10 to about 25, about 15 to about 20, about 5 to about 15, about 5 to about 20, about 5 to about 25, about 10 to about 25, about 10 to about 20, about 10 to about 15, about 15 to about 25, about 14 to about 16, about 12 to about 18, or about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30, wt.% percent actives, based on a total weight of the VFA control agent.
  • all values and ranges of values including and between those set forth above are hereby expressly contemplated for use herein.
  • the concentration of the of a particular active agent e.g. a chelator or sequestrant, the surfactant or dispersant, or both
  • the particular proportions of the VFA control agent are not particularly limited, and may be adjusted based on considerations relevant to the, e.g. storage, transportation, dosing, handling, ease of use, etc.
  • the amount of the VFA control agent utilized in the method itself can vary, and will be based on the active concentration (e.g. wt.% actives) described above.
  • the VFA control agent comprises additional components aside from the surfactant or chelant.
  • the VFA control agent comprises the surfactant or dispersant, a defoamer, a thickening agent, and water.
  • defoamers also known as an anti-foams
  • defoamers comprising fatty acids such as carboxylic acids with long aliphatic chains, may be used, including those that are saturated or unsaturated and branched or unbranched (i.e., linear).
  • fatty acids include those including unbranched chains having an even number of carbon atoms, such as from 4 to 28, as well as alcohols and/or esters thereof.
  • defoamers include silicone based polymers, such as those comprising hydrophobic silica, glycols and/or polyethers derived from ethylene oxide, propylene oxide, and combinations thereof, alkyl phosphates (e.g. tri-butyl phosphate), and the like, as well as combinations thereof.
  • the VFA control agent comprises a defoamer that is an emulsion comprising hydrophobic silica.
  • the defoamer is chosen from fatty acids, alcohols, and esters thereof; hydrophobic silicas; glycols; tri-butyl phosphates; and combinations thereof.
  • the defoamer comprises a glycol further defined as polyether derived from ethylene oxide, propylene oxide, and combinations thereof.
  • the defoamer comprises, alternatively is, an aqueous hydrophobic silica.
  • the defoamer may compose any practical amount of the VFA control agent, e.g. by weight and/or volume.
  • the VFA control agent comprises the defoamer in an amount of from about 1 to about 20 wt.% actives based on a total weight of the VFA control agent.
  • the defoamer is present in the VFA control agent in an amount of from about 1 to about 18, about 2 to about 18, about 5 to about 15, about 10 to about 15, about 5 to about 10, about 8 to about 12, about 10 to about 20, or about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20, wt.% actives, based on a total weight of the VFA control agent.
  • the VFA control agent may be provided in any form, such as a solution, suspension, dispersion, etc.
  • the VFA control agent comprises the surfactant and the defoamer and is in the form of a solution, an emulsion, a dispersion, etc.
  • a thickening agent may be utilized as well.
  • the VFA control agent is an emulsion or dispersion, e.g. when formulated with a hydrophobic silica-containing defoamer, a thickening agent is typically used.
  • a thickening agent may be utilized even if the VFA control agent is not a dispersion or emulsion.
  • Suitable thickening agents are not particularly limited and may be any known in the art.
  • the VFA control agent comprises a thickening agent chosen from modified cellulosics, such as hydroxyethyl cellulose, and modified polyacrylates, such as alkali soluble emulsions (ASE), cross-linked polyacrylic acids, and combinations thereof.
  • the thickening agent is a high-molecular weight cross-linked polyacrylic acid.
  • the thickening agent may compose a proportion of the VFA control agent of from greater than zero to an amount of about 3 wt.% actives, based on a total weight of the VFA control agent.
  • the VFA control agent comprises the thickening in an amount of from about 0.5 to about 2.5, about 1.0 to about 2.0, about 1.5 to about 2.0, about 1.0 to about 1.5, about 0.5 to about 1.0, about 0.5 to about 2.0, about 2.5 to about 3.0, about 1.0 to about 1.25, about 1.25 to about 1.50, about 1.25 to about 1.75, about 1.5 to about 1.75, about 1.75 to about 2.0, wt. actives, based on a total weight of the composition.
  • the VFA control agent may comprise water.
  • the water may be included in the VFA control agent in an amount such that the total wt.% actives is 100 parts or 100 wt.% actives.
  • the water itself is not particularly limited and may include tap water, deionized water, distilled water, etc.
  • the water of the VFA control agent is may be the same or different than water utilized in the aqueous system/process flow described herein.
  • the VFA control agent comprises the surfactant, the defoamer, the thickening agent, and water.
  • the VFA control agent comprises a linear alkylbenzene sulfonate surfactant having the structure: wherein X is a counter ion and each subscript m and n is independently from 0 to 16, with the proviso that m + n is from 4 to 16.
  • the linear alkylbenzene sulfonate surfactant is present in an amount of from about 5 to about 30 wt.% actives, based on a total weight of the VFA control agent.
  • the VFA control agent further comprises the defoamer, present in an amount of from about 1 to about 20 wt.% actives, and a thickening agent present in an amount of from greater than zero to an amount of about 3 wt.% actives, each based on a total weight of the VFA control agent.
  • the surfactant comprises or is sodium dodecylbenzene sulfonate
  • the thickening agent comprises or is hydrophobic silica
  • the thickening agent comprises or is a cross-linked polyacrylic acid, or any combination thereof.
  • the VFA control agent comprises the chelator or sequestrant in an amount of from about 10 to about 100, alternatively from about 10 to about 90 wt.% actives, based on a total weight of the VFA control agent.
  • the VFA control agent comprises the chelator or sequestrant in an amount of from about 10 to about 25, about 15 to about 20, about 5 to about 15, about 5 to about 20, about 5 to about 25, about 10 to about 25, about 10 to about 20, about 10 to about 15, about 15 to about 25, about 14 to about 16, about 12 to about 18, or about 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 wt.% actives, based on a total weight of the VFA control agent.
  • all values and ranges of values including and between those set forth above are hereby expressly contemplated for use herein.
  • the VFA control agent further comprises sodium bisulfite.
  • the sodium bisulfite may compose any practical amount of the VFA control agent, e.g. by weight and/or volume, which will be selected to provide the process flow with an effective amount thereof.
  • an effective amount of the sodium bisulfite in the process flow may be from about 5 to about 1,000 ppm, such as from about 10 to about 500, alternatively from about 15 to about 400, alternatively from about 20 to about 300, alternatively from about 25 to about 250, alternatively from about 25 to about 200, alternatively from about 25 to about 150 ppm.
  • the effective amount of the sodium bisulfite will typically be selected on the basis of performance of the VFA control agent to reduce, eliminate, stop, and/or prevent production of one or more VFAs in the process flow.
  • the VFA control agent comprises the sodium bisulfite in an amount sufficient to treat the process flow with the surfactant, dispersant, chelator, and/or sequestrant in a 1 :5 to 10: 1 ratio with the sodium bisulfite, such a ratio of from about 1 :2 to about 10: 1, alternatively of from about 1 :2 to about 5: 1, alternatively of from about 1 :2 to about 3: 1, alternatively of from about 1 : 1 to about 2: 1, ratio with the sodium bisulfite.
  • the VFA control agent may comprise the sodium bisulfite in any amount, such as an amount of from about 1 to about 80 wt.% actives, such as an amount of from about 2 to about 75, alternatively from about 5 to about 50 wt.% actives, based on a total weight of the VFA control agent.
  • amounts of sodium bisulfite outside these ranges may also be utilized.
  • all values and ranges of values including and between those set forth above are hereby expressly contemplated for use herein.
  • the treatment can be carried out continuously or discontinuously.
  • the term “continuously” means that the VFA control agent may be added to the process flow without interruption
  • the term “discontinuously” means that the addition of the of the VFA control agent to the process flows is instead performed by means of pulses of a predetermined length, e.g. interrupted by periods free from treatment.
  • any amount of the VFA control agent added to the process flow e.g. as an “inflow”, is performed to achieve a desired localized concentration in the process flow.
  • treating the process flow comprises adding the VFA control agent in an amount sufficient to inhibit microbiological production of one or more VFA, e.g. via inhibition of amylase enzymes, biofilm formation, dispersion of microbes, etc.
  • treating the process flow comprises adding the VFA control agent in an amount effective to give an active concentration in the process flow (e.g. of chelator or sequestrant, the surfactant or dispersant, or both) of from about 1 to about 1000 ppm, such as from about 5 to about 750 ppm, alternatively from about 5 to about 500 ppm, alternatively from about 10 to about 500 ppm, alternatively from about 15 to about 500 ppm, alternatively from about 20 to about 500 ppm, alternatively from about 20 to about 400 ppm, alternatively from about 20 to about 300 ppm, alternatively from about 20 to about 250 ppm, alternatively from about 25 to about 250 ppm, alternatively from about 25 to about 200 ppm, alternatively from about 25 to about 150 ppm, alternatively from about 25 to about 100 ppm, alternatively from about 50 to about 100 ppm.
  • an active concentration in the process flow e.g. of chelator or sequestrant, the surfactant or dispersant, or both
  • the method may further comprise treating the process flow with a biocidal agent, i.e., in sequence with or simultaneously to the VFA control agent.
  • a biocidal agent i.e., in sequence with or simultaneously to the VFA control agent.
  • the method utilizes a synergistically effective amount of the VFA control agent and the biocide to provide improved VFA control with reduced overall loading of chemical additives.
  • the biocidal agent is not particularly limited, and may comprise any suitable biocidal agent compatible with the process flow being treated.
  • biocidal agent is used herein to describe a composition or compound that acts as a microbiocide or biocide under the treatment conditions described herein, which will be understood by those of skill in the art to refer to chemical substance capable of controlling microbes (e.g. bacteria) in a selective way. In this sense, the microbial production of new amylase enzymes can be prevented or at least controlled be inhibiting microbial growth with the biocidal agent.
  • suitable biocides include oxidizing and nonoxidizing biocides, as well as combinations thereof, which are known in the art to reduce the number of active/alive/intact microbes in the process flow.
  • the method comprises treating the process flow with an oxidizing biocide (i.e., in addition to the VFA control agent).
  • oxidizing biocides include oxidants, optionally combined with supporting compounds such as nitrogen compounds.
  • oxidants generally include halo compounds such as chlorine, alkali and alkaline earth hypochlorite salts, hypochlorous acid, chlorinated isocyanurates, bromine, alkali and alkaline earth hypobromite salts, hypobromous acids, bromine chloride, chlorine dioxides, as well as oxo compounds such as ozone, hydrogen peroxide, peroxy compounds such as peracetic acid, performic acid, percarbonates, etc.
  • Additional examples of oxidizing biocides generally include persulfate salts, halogenated hydantoins (e.g.
  • monohalodimethylhydantoins such as monochlorodimethylhydantoin, dihalodimethylhydantoins such as chlorobromodimethylhydantoin, etc.
  • monochloramines monobromamines, dihaloamines, trihaloamines, as well as combinations of any of the above.
  • the nitrogen compounds typically include ammonium salts, ammonia, urea, hydantoin, isothiazoline-l,l-dioxide, ethanolamine, pyrrolidone, 2-pyrrolidone, ethylene urea, N-methylolurea, N-methylurea, acetylurea, pyrrole, indole, formamide, benzamide, acetamide, imidazoline, or morpholine.
  • the oxidizing biocide comprises the reaction product of the nitrogen compound and the oxidant, such as the reaction product of a urea reacted with a hypochlorite.
  • the oxidizing biocide comprises monochloramine (MCA), such that the method further comprises treating the process flow with monochloramine (MCA).
  • the method comprises treating the process flow with a nonoxidizing biocide.
  • the non-oxidizing biocide comprises a thiazole- based microbiocide (e.g. methylchloroisothiazolinone, such as 5-chloro-2-methyl-4-isothiazolin-3- one (OMIT), 2-methyl-4-isothiazolin-3-one (MIT), etc.), a carbamate-based microbiocide (e.g. an ammonium carbamate, dimethyl dithiocarbamate), bronopol (i.e., 2-bromo-2-nitropropane-l,3- diol), and the like, as well as combinations thereof.
  • a thiazole- based microbiocide e.g. methylchloroisothiazolinone, such as 5-chloro-2-methyl-4-isothiazolin-3- one (OMIT), 2-methyl-4-isothiazolin-3-one (MIT), etc.
  • non-oxidizing biocides such as 2, 2-dibromo-3 -nitrilopropionamide (DBNPA), as well as antimicrobial glutaraldehydes and quaternary ammonium compounds known in the art.
  • DBNPA 2, 2-dibromo-3 -nitrilopropionamide
  • antimicrobial glutaraldehydes and quaternary ammonium compounds known in the art.
  • the biocidal agent is added to the process flow in an amount effective to give an active concentration of the oxidizing biocide (i.e., in a localized portion of the process flow) of from about 0.1 to about 250 ppm, alternatively from about 1 to about 250 ppm, alternatively from about 5 to about 250 ppm, alternatively from about 100 to about 250 ppm, alternatively from about 100 to about 200 ppm, alternatively of about 150 ppm.
  • the biocidal agent is generally added to the process flow in an amount effective to give an active concentration of the non-oxidizing biocide in the process flow of from about 0.1 to about 1000 ppm, alternatively from about 1 to about 500 ppm, alternatively from about 1 to about 250 ppm, alternatively from about 1 to about 100 ppm, alternatively from about 1 to about 50 ppm.
  • the amount of the biocidal agent is selected to result in a residual chlorine content of less than about 5 ppm.
  • the biocidal agent comprises monochloramine (MCA) and the VFA control agent comprises at least one of an alkylbenzene sulfonate, a polyamino polyether methylene phosphonic acid (PAPEMP), a bis(hexamethylenetriaminepenta(methylene phosphonic acid)) (BHMTAP)), a diethylenetriamine penta(methylene phosphonic acid) (DTPMP), and a sodium hexametaphosphate (SHMP).
  • PAPEMP polyamino polyether methylene phosphonic acid
  • BHMTAP bis(hexamethylenetriaminepenta(methylene phosphonic acid)
  • DTPMP diethylenetriamine penta(methylene phosphonic acid)
  • SHMP sodium hexametaphosphate
  • the biocidal agent comprises a methylchloroisothiazolinone, an ammonium carbamate, bronopol, or a combination thereof
  • the VFA control agent comprises at least one of an alkylbenzene sulfonate, a polyamino polyether methylene phosphonic acid (PAPEMP), a bis(hexamethylenetriaminepenta(methylene phosphonic acid)) (BHMTAP), a diethylenetriamine penta(methylene phosphonic acid) (DTPMP), and a sodium hexametaphosphate (SHMP).
  • PAPEMP polyamino polyether methylene phosphonic acid
  • BHMTAP bis(hexamethylenetriaminepenta(methylene phosphonic acid)
  • DTPMP diethylenetriamine penta(methylene phosphonic acid)
  • SHMP sodium hexametaphosphate
  • the method may comprise treating the process flow with independent (i.e., separate) additions of the VFA control agent and the biocidal agent.
  • the method may comprise treating the process flow with a single composition comprising both the VFA control agent and the biocidal agent
  • the present embodiments provide an effective solution to control contamination, odor, and starch content in the process flow and resulting products being prepared therewith.
  • the VFA control agent optionally in conjunction with the biocidal agent, is utilized to reduce and/or prevent the degradation of starch present in the process flow, providing a process improvement that may lead to increased retention, and thus increased strength parameters, in the final product.
  • the method also provides for reduced starch content in the process water upon recirculation (e.g. white water).
  • the method may be employed with recycled fibers to improve runnability, optimize retention, and increase the strength properties of the product being prepared from the process flow.
  • the composition may comprise one or more additional components. These additional components may be functional (i.e., provide a desired chemical reach vity/functi on to the composition) or may be simply included to formulate the composition in a desired fashion.
  • the composition may comprise a carrier vehicle, which may itself comprise one or more solvents, dispersants, etc.
  • the composition comprises water.
  • the composition comprises a water-miscible or water-soluble organic solvent, such as a liquid alcohol, alkylamine, etc.
  • a water-miscible or water-soluble organic solvent such as a liquid alcohol, alkylamine, etc.
  • the composition comprises a C1-C6 alcohol, such as a methanol, ethanol, propanol, butanol, pentanol, hexanol, phenol, or combination thereof.
  • the composition comprises an organic solvent selected from the group of ethanol, isopropanol, dodecanol, and combinations thereof.
  • the composition comprises isopropanol.
  • Equipment A Gas Chromatograph (GC) equipped with a flame ionization detector (FID) (e.g. Agilent 6890N GC or equivalent) equipped with an autosampler is utilized with a Fused Silica Capillary Column (e.g. Agilent DB-WAX UI, 30 m x 0.53 mm x 1.0 pm).
  • FID flame ionization detector
  • VFA mixture Free Fatty Acid Test Mixture, 1,000 ug/ml, water, Restek # 35272(1 mL) is weighed into a volumetric flask (10 ml) and brought to volume with a standard diluent (0.25% phosphoric acid/ 1% methanol in water) to give a 100 ppm working standard.
  • a portion (2.5 mL) of the 100 ppm working standard is transferred to a separate volumetric flask (5 mL) and brought to volume with the standard diluent to give a 50 ppm working standard.
  • the preceding process is repeated with another portion (0.1 mL) of the standard VFA to give a 10 ppm working standard, and subsequently a 5 ppm working standard, respectively.
  • a portion (0.5 mL) of the 10 ppm working standard is transferred to a separate volumetric flask (5 mL) and brought to volume with the standard diluent to give a 1 ppm working standard.
  • Sample Preparation An aliquot (0.5 mL) of a sample is taken from a shaken sample well via pipet and transferred into a glass vial with the standard diluent (4.5 mL). The glass vial is then capped and vortexed, and a portion of the contents transferred into a GC vial.
  • GC Standardization The GC is standardized by injecting 2.0 pL of each working standard using the instrument parameters listed in Table 2 below. The areas for the standards are used to create a linear calibration curve in GC software (e.g. Agilent Chemstation or equivalent).
  • Calibration A working standard (10 or 50 ppm, 2 pL) is injected at the beginning and end of each set of samples, and intermittently within long sequences of sampling, and the concentration determined and compared to the to the standard curve to maintain calibration (+/- 5% of standard curve).
  • the samples are then dosed with a VFA Control Agent, capped, and incubated with shaking at 35 °C. Aliquots of each sample are taken at various times post-dosage and analyzed via GC as described above, with each sample bottle capped and incubated between samplings along with an uninoculated control (sterile TGE broth) and an inoculated control (untreated). % VFA reduction is reported based on the relative VFA concentration (ppm) of a sample determined against the inoculated/untreated control.
  • the parameters and results of Examples 1-10 are set forth in Table 3 below.
  • Examples 24-35 Additional examples are prepared according to the general procedure above to demonstrate the efficacy of combinations of two different VFA Control Agents at different relative concentrations, to give Examples 24-35.
  • an expected reduction value is calculated by adding the % VFA reduction of the two single- VFA Control Agent examples run at the same concentration of VFA Control Agent utilized. In this fashion, the difference in observed performance (% VFA reduction) of the combination of VFA Control Agent from the expected value represents the synergy demonstrated.
  • the parameters and results of Examples 24-35 are set forth in Tables 6-7 below.
  • the VFA Control Agents reduce VFA content over time. Moreover, addition of Biocides in synergistic combinations enhances performance overall, and allows for a reduction in concentration of the VFA Control Agent needed (e.g. from 250 or 500 ppm to 50 or 100 ppm). As also shown, use of the VFA Control Agents in synergistic combinations provides for increased performance in terms of VFA reduction over time as compared to the same VFA Control Agents when used alone in the same concentrations. Moreover, such synergistic combinations demonstrate improved performance in reducing VFA content over time, beyond the expected cumulative/additive performance of the individual VFA Control Agents. In this sense, a synergistic performance may be defined as a % VFA reduction at least 2 hours after treatment of at least Im alternatively at least 4 % greater than the cumulative individual % VFA reduction of the VFA Control Agents utilized.
  • any ranges and subranges relied upon in describing various embodiments of the present invention independently and collectively fall within the scope of the appended claims, and are understood to describe and contemplate all ranges including whole and/or fractional values therein, even if such values are not expressly written herein.
  • One of skill in the art readily recognizes that the ranges and subranges enumerated herein sufficiently describe and enable various embodiments of the present invention, and such ranges and subranges may be further delineated into relevant halves, thirds, quarters, fifths, and so on.
  • a range “of from 0.1 to 0.9” may be further delineated into a lower third, i.e., from 0.1 to 0.3, a middle third, i.e., from 0.4 to 0.6, and an upper third, i.e., from 0.7 to 0.9, which individually and collectively are within the scope of the appended claims, and may be relied upon individually and/or collectively and provide adequate support for specific embodiments within the scope of the appended claims.
  • a range such as “at least,” “greater than,” “less than,” “no more than,” and the like, it is to be understood that such language includes subranges and/or an upper or lower limit.
  • a range of “at least 10” inherently includes a subrange of from at least 10 to 35, a subrange of from at least 10 to 25, a subrange of from 25 to 35, and so on, and each subrange may be relied upon individually and/or collectively and provides adequate support for specific embodiments within the scope of the appended claims.
  • An individual number within a disclosed range may be relied upon and provides adequate support for specific embodiments within the scope of the appended claims.
  • a range “of from 1 to 9” includes various individual integers, such as 3, as well as individual numbers including a decimal point (or fraction), such as 4.1, which may be relied upon and provide adequate support for specific embodiments within the scope of the appended claims.

Abstract

L'invention concerne un procédé de régulation de la teneur en acides gras volatils (AGV) dans des procédés de fabrication de la pâte à papier, de papier et/ou de carton. Le procédé peut être utilisé pour apporter des améliorations au processus sous la forme d'une réduction de la contamination microbienne et de l'odeur, d'une réduction de la dégradation de l'amidon, d'une optimisation de la rétention et d'une amélioration du comportement machine. Le procédé consiste à traiter un flux de traitement comprenant un matériau cellulosique contenant de l'amidon avec un agent de régulation des AGV. L'agent de régulation des AGV est non biocide, comprend un surfactant ou un dispersant, un chélateur ou un séquestrant, ou une combinaison de ceux-ci, est en mesure d'inhiber l'activité de l'amylase dans le flux du processus, et est utilisé en quantité suffisante pour inhiber la production microbiologique d'un ou de plusieurs AGV. Le procédé comprend facultativement le traitement du flux de processus avec un agent biocide en combinaison avec l'agent de régulation des AGV.
PCT/US2022/082097 2021-12-22 2022-12-21 Procédé de régulation de la teneur en acides gras volatils dans une pâte à papier WO2023122637A1 (fr)

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Citations (2)

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Publication number Priority date Publication date Assignee Title
EP0726357A1 (fr) * 1995-02-07 1996-08-14 Betz Laboratories Inc. Inhibition de la production anaérobique des acides gras volatils et de l'hydrogène par des bactéries
US9091024B2 (en) * 2012-06-05 2015-07-28 Buckman Laboratories International, Inc. Method to preserve native starch present in pulp in a papermaking process

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0726357A1 (fr) * 1995-02-07 1996-08-14 Betz Laboratories Inc. Inhibition de la production anaérobique des acides gras volatils et de l'hydrogène par des bactéries
US9091024B2 (en) * 2012-06-05 2015-07-28 Buckman Laboratories International, Inc. Method to preserve native starch present in pulp in a papermaking process

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
JONES DAVID R.: "Solving Volatile Fatty Acids Issues in Recycled Packaging Operations", WORLD PULP & PAPER THE INTERNATIONAL REVIEW FOR THE PULP AND PAPER INDUSTRY, 1 January 2016 (2016-01-01), XP093077844, Retrieved from the Internet <URL:https://www.buckman.com/resources/solving-volatile-fatty-acids-issues-in-recycled-packaging-operations/> [retrieved on 20230831] *

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