Abstract: The invention relates to a method for producing an absorbent fiber product, starting with a parent fiber product that comprises fibers that, on the one hand, lie at a statistical distance from one another and, on the other hand, make contact with one another at contact points. The method comprises treating the parent fiber product with a fluid medium in such a way that the fibers are at least partially wetted and the fluid medium is then rapidly evaporated by irradiation, so that the evaporation pressure generated by the evaporating fluid medium has a kinematic effect on the fibers, which increases the distance between them. In this way the risk of inadvertent, in particular, thermal damage to the fibers is eliminated. Furthermore, the intrinsic fiber structure is left unaffected, or is only affected in a controlled manner. This prevents the uncontrolled destruction of the fiber structure and a detrimental effect on the fiber product, for example, to its tear resistance when wet.

Abstract: Biomass (e.g., plant biomass, animal biomass, and municipal waste biomass) is processed to produce useful products, such as fuels. For example, systems are described that can use feedstock materials, such as cellulosic and/or lignocellulosic materials, to produce ethanol and/or butanol, e.g., by fermentation.

Abstract: The invention relates to a new pulp, which is derived from lignocellulosic material subjected to agitation in an aqueous tetra-alkylammonium salt solution under microwave irradiation. The invention relates also to a process for pulping lignocellulosic material and to a process for softening lignocellulosic material. The treated material is preferably wood, softwood or hardwood.

Abstract: This invention relates to pulp reactivity enhancement. In particular, the invention relates to a method of producing an alkali cellulose which includes steps of providing a pulp and subjecting the pulp to an alkaline treatment to produce the alkali cellulose in the presence of a spacer capable of entering the holes in the interfibrillar spaces of the cellulose fibres. The spacer enters the holes in the interfibrillar spaces of the cellulose fibres, particularly those created by the removal of hemi-cellulose, reducing the tendency for collapse to occur, for example during the subsequent pressing step. Examples of suitable spacers are polyethylene glycols, polyvinyl alcohols and polyacrylates.

Abstract: Methods of producing cellulosic or lignocellulosic materials for use in papermaking include treating a cellulosic or lignocellulosic dry feedstock having a first average molecular weight with ionizing radiation, and controlling the dose of ionizing radiation such that the average molecular weight of the feedstock is reduced to a predetermined level. A method of producing an irradiated paper product includes treating a paper product including a first carbohydrate-containing material having a first molecular weight with ionizing radiation, and controlling the dose of ionizing radiation so as to provide an irradiated paper product with a second carbohydrate-containing material having a second molecular weight higher than the first molecular weight. Pulp and paper products are produced.

Abstract: Irradiated lignocellulosic or cellulosic materials are provided which contain carboxylic acid groups and/or other functional groups not present in a naturally occurring cellulosic or lignocellulosic material from which the irradiated material was obtained

Abstract: A method is provided for subjecting a material which is partially in a solid state and partially in a liquid state to explosive forces. The method includes containing the material in a vessel having a length in a first direction and a width in a second direction perpendicular to the first direction, the length being greater than the width; subjecting the material to the explosive forces in the vessel, the explosive forces being caused by introducing energy to the material by discharging a capacitor through a capacitor discharge electrode located within the material; and removing the material from the vessel after being subjected to the explosive forces.

Abstract: The present invention is a rapid method of determining the concentration of the major components in a chemical stream. The present invention is also a simple, low cost, device of determining the in-situ concentration of the major components in a chemical stream. In particular, the present invention provides a useful method for simultaneously determining the concentrations of sodium hydroxide, sodium sulfide and sodium carbonate in aqueous kraft pulping liquors through use of an attenuated total reflectance (ATR) tunnel flow cell or optical probe capable of producing a ultraviolet absorbency spectrum over a wavelength of 190 to 300 nm. In addition, the present invention eliminates the need for manual sampling and dilution previously required to generate analyzable samples.

Abstract: An apparatus is disclosed for controlling the consistency of a flow of stock solution flowing from a header to a slice lip of a headbox of a papermaking machine so that the cross machine direction consistency profile of a resultant web is controlled. The apparatus includes a flow channel which is disposed within the headbox between the header and the slice lip. The flow channel has an upstream and a downstream end such that the flow of the stock solution is in a flow direction from the upstream end towards the downstream end of the flow channel. The flow channel includes a primary channel having a first and a second extremity such that the flow of the stock solution is through the primary channel from the first extremity to the second extremity of the primary channel. A supply channel has a first and a second end and is disposed downstream relative to the primary channel for the flow therethrough of a supply portion of the flow of the stock solution.

Abstract: A system and method for altering the tack of a material, namely a polymer used as an adhesive, also known as stickies, or pitch. The present invention reduces the tack of the stickies and pitch by exposing the materials for a short duration to low-energy pulsed electrical discharges between a pair of electrodes that are submerged in a liquid medium, such as a fiber stream, water, a pulp slurry, or whitewater.

Abstract: This invention provides a process for treating chemical woodpulp, or chemical cellulose including cotton linter, including the step of applying an electron processing technology (EPT) step to chemical woodpulp, or chemical cellulose, as the case may be, on an in-line basis to provide control of pulp viscosity or degree of polymerization (DP). The invention also provides a method of process control in treating the aforementioned woodpulp or cellulose, including the step of using radiation dose-viscosity relationship curve for applying an EPT step on an in-line basis. The in-line EPT step may, in one form of the invention, replace and hence eliminate a chemical DP reduction step.

Abstract: The method is for treating a liquid or slurry with an ultrasonic energy. A movable endless member is provided that is permeable to a liquid. A transverse foil is disposed below the member and extends across the member and a transducer is in operative engagement with the foil. The member is moved about rollers. The transducer generates pressure pulses into the foil to form implosion bubbles in the liquid disposed above the member. The implosion bubbles have a first diameter (d1). A gap is formed between the member and the foil. The gap represents a distance (d2) that is less than the diameter (d1) of the bubbles to prevent any bubbles of critical size to be captured in the gap.

Abstract: A lignocellulose material is cooked by means of an alkaline cooking liquor containing polysulfides in the presence of a quinone-hydroquinone compound, of which the oxidation-reduction potential in the form present during the cooking, which potential is a value calculated as a standard oxidation-reduction potential (Ea) with a hydrogen ion activity of 1, is within a range of from 0.12 to 0.25V to the standard hydrogen electrode potential. It is thereby possible to cook the lignocellulose material with a low Kappa number and in good yield and at the same time, to reduce the amount of the chemical solution used and to reduce the load on a recovery boiler.

Abstract: A method of producing pulp for use in making paper products using microwave radiation to pretreat the source of pulp prior further processing. Practising the method of the invention results in substantial energy savings while decreasing environmental impact and improving paper qualities.

Abstract: This invention provides a process for treating chemical woodpulp, or chemical cellulose including cotton linter, including the step of applying an electron processing technology (EPT) step to chemical woodpulp, or chemical cellulose, as the case may be, on an in-line basis to provide control of pulp viscosity or degree of polymerisation (DP). The invention also provides a method of process control in treating the aforementioned woodpulp or cellulose, including the step of using radiation dose-viscosity relationship curve for applying an EPT step on an in-line basis. The in-line EPT step may, in one form of the invention, replace and hence eliminate a chemical DP reduction step.

Abstract: A resonant chamber that produces an ultrasonic energy field about a central axis of the chamber to separate contrary matter from a working material. The resonant chamber has a circular cross section and utilizes a series of transducer elements to generate an ultrasonic transverse wave disposed about the internal longitudinal axis of the chamber. In addition, a driver circuit is provided that is able to efficiently excite the transducer elements to generate the ultrasonic transverse wave with a minimum of heat dissipation and power loss.

Abstract: An Improved method of recovering and beneficially treating cellulosic fibers from compacted waste material containing waste paper before fibrillation by confining the waste material within a closed chamber containing a beneficially treating fluid and subjecting the contents of the closed chamber to one or more cycles of consecutive additions of beneficially treating fluid and removals of beneficially treating fluid.

Abstract: System and method for oxidizing contaminants to alter specific properties, such as tack, of contaminants. The present invention reduces the tack of the stickies and pitch by exposing the materials for a short duration to low-energy pulsed electrical discharges between a pair of electrodes that are submerged in a liquid medium, such as a fiber stream, water, a pulp slurry, or whitewater. An electrical discharge in the liquid medium oxidizes materials, which may be dissolved or suspended therein, such as stickies, pitch, sulfide, ink, toner, and other substances, thereby reducing tack, odor, and/or zeta potential, as well as producing other desirable effect.

Abstract: The invention relates to a method of bleaching and/or delignifying cellulose, in which (a) a sodium hydroxide solution and a peroxydisulphate solution are first of all produced by electrolysis of a sulphate, (b) the peroxydisulphate solution is converted by hydrolysis into a Caro's acid/caroate solution, (c) said Caro's acid/caroate solution is left to cool and (d) used immediately as a bleaching solution for bleaching and/or delignifying cellulose, the Caro's acid/caroate solution becoming neutralised upon introduction into the bleaching solution.

Abstract: This invention relates to a novel on-line pulp digester control system. More particularly, this invention pertains to a novel control system which employs real time measurements from ion mobility spectrometry to automatically rapidly and continuously determine the physical and chemical characteristics of wood chip feedstock being fed into a pulp digester and thereby maximize process efficiencies, minimize chemical and energy consumption and improve product uniformity.

Abstract: The invention relates to a method of bleaching and/or delignifying cellulose, in which

Abstract: The invention relates to a fluorescence microscopy technique for measuring physical and chemical properties of individual fiber-like particles. Fluorescence intensity per unit length is shown to be proportional to the fiber coarseness. In addition, other fiber properties such as fiber length, width and wall thickness can be obtained from fluorescence images, and lignin content from fluorescence spectra. The present invention will provide a process for determining the uniformity of pulp samples in terms of the physical and chemical properties of the individual fiber-like particles, particularly wood pulp fibers.

Abstract: The present invention relates to a method and assembly for controlling the behaviour of particulate matter such as mist and dust occurring in the manufacture of paper and board. In the method, a web (1) is passed to web treatment equipment (22, 23) wherein at least one treatment step is applied to the web (1) causing the emission of said particulate matter (24). According to the method, in the vicinity of the emission point (21) of said particulate matter are placed at least two electrodes (25, 26) and at least one electrode, called a counter-electrode (26), is taken to a low potential.

Abstract: Online methods of quantitatively and qualitatively monitoring the biofilm and deposition organic and inorganic contaminants in paper processing equipment provided. Spectroscopic methods, and more specifically attenuated total reflectance techniques are disclosed.

Abstract: Method for improving the formation of a web material in a wire machine, including dispersing existing flocks in stock which is transported along a transport direction from an inlet box onto a plurality of wire sections which are arranged after each other along the direction of travel, counteracting the reformation of flocks in the stock on the wire by furnishing ultrasound energy as ultrasound waves with frequencies between 15 and 75 kHz to the stock on the wire sections. The ultrasound has a higher frequency within at least one section which is closer to the inlet box than a subsequent section further away from the inlet box, within which subsequent section the ultrasound has as lower frequency.

Abstract: Measurement device for quantitatively detecting constituents of a pulp/fluid mixture for paper and/or cardboard production. The device includes at least one radiation source for irradiating the mixture in a number of definite, different wavelength ranges. The device also includes at least one sensor for measuring the intensity of radiation that has been influenced by the mixture, and at least one set of measurement electronics. Each sensor detects only one of the definite, different wavelength ranges of the radiation at a particular time.

Abstract: An electrochemical process is provided for treatment of molten kraft smelt produced from black liquor in a kraft recovery boiler. Treated smelt can be contacted with water to produce white liquor which can be re-used or recycled in the kraft process.

Abstract: Process and measurement device for quantitatively detecting constituents of a pulp/fluid mixture for paper and/or cardboard production. The device includes at least one radiation source for irradiating the mixture in a number of definite, different wavelength ranges. The device also includes at least one sensor for measuring the intensity of radiation that has been influenced by the mixture, and at least one set of measurement electronics. Each sensor detects only one of the definite, different wavelength ranges of the radiation at a particular time. The process includes irradiating the mixture with at least one radiation source, the irradiation occurring in a number of definite, different wavelength ranges; and measuring the intensity of radiation that has been influenced by the mixture by at least one sensor. Each sensor detects only one of the definite, different wavelength ranges of the radiation at a particular time.

Abstract: Apparatus and process in a machine for at least one of producing and processing the fibrous web. The apparatus includes an essentially water-free traveling surface adapted to guide the fibrous web, and a measuring device positioned and adapted to detect moisture content of the fibrous web while the fibrous web is supported by the essentially water-free traveling surface. The process includes guiding the fibrous web on the essentially water-free traveling surface, and detecting a moisture content of the fibrous web while the fibrous web is supported by the essentially water-free traveling surface.

Abstract: A method and apparatus for subjecting a material in a liquid to explosive forces is provided. The method and apparatus involve a vessel having a length greater than it width. The vessel has a top which is quickly and easily lockable and removable so as to increase the material processing rate of the vessel.

Abstract: An increasing problem with the pulping chemical recovery system, is the presence of chloride and potassium in the recovery boiler. Chloride and potassium increase inter alia the stickiness of carryover deposits and dust particles to the recovery boiler tubes, which accelerate fouling, corrosion and plugging of the recovery boiler. As the environmental legislation becomes more stringent, the degree of system closure increases. The present invention relates to a process by which the collected precipitator dust is leached, at a temperature exceeding 50.degree. C., for a residence time sufficient to get a chloride and potassium enriched leach solution and to remove at least a part of the content of metal ions in a solid phase. Said leach solution is electrochemically treated, preferably in an electrodialysis cell, in order to remove at least a part of the chloride and potassium therein. By the present process, the problem of sticky deposits in the recovery boiler can be substantially reduced.

Abstract: The present invention relates to a method of processing white liquor obtained from the causticization stage of a pulp mill. According to the method, the white liquor, which principally contains sodium hydroxide (6) and sodium sulfide, is oxidized into polysulfide liquor (3), whereby the sodium sulfide is oxidized most advantageously with the help of a catalyst and an oxidizer such as air substantially into sodium polysulfide (7) and sodium thiosulfate. The method according to the invention is characterized in that the sodium hydroxide (6) contained in the white liquor is separated from the white liquor prior to the oxidizing step or from the polysulfide liquor (3) after the oxidizing step either entirely or partly by means of a diffusion dialysis process (4). The invention is further characterized in that the sodium hydroxide (6) separated from the white liquor is returned to the chemical circulation of the pulp mill.

Abstract: This invention is related to a process for producing pulp from a cellulosic starting material, wherein an aqueous process effluent is purified from metal impurity cations. This process comprises that the effluent is purified by an electro-chemical membrane treatment in an electrochemical membrane device comprising a unit cell through which an electric current is passed between an anode side and a cathode side of said cell, said cell comprising at least two ion permeable membranes forming between them at least one compartment, said effluent being fed into an effluent feed compartment in said cell, in which the effluent is purified by removing with the electric current metal impurity cations from the effluent through a cation selective membrane on the cathode side of said compartment, and withdrawing from said compartment the purified effluent. The purified effluent may be recirculated to the pulp mill process, e.g. as washing water.

Abstract: This invention relates to an environmentally preferred process for the delignification of a cellulosic biomass comprising pulp. The process uses the oxidative properties of nascent oxygen to complete pulping and bleaching operations. The process may be used in a pulping stage, a bleaching stage or can be used for both the pulping and bleaching stages of a delignification process. The process does not rely on large volumes of environmentally offensive chemicals such as caustic soda, sulfur, and chlorine to achieve delignification of the pulp.

Abstract: The present invention relates to an environmental-friendly process for reducing the content of chloride in a liquor inventory of a chemical pulp mill. According to the invention, in a recovery system for pulping chemicals containing sulphur and an alkali metal, precipitator dust formed in a recovery boiler is collected and withdrawn, dissolved in water and electrolyzed for production of chlorine or hydrochloric acid in the anolyte. Since the dust normally contains a large amount of sodium sulphate, sulphuric acid and sodium hydroxide can also be produced in the electrolysis. To reduce the content of impurities, before the electrolysis, the pH of the aqueous solution is adjusted to above about 10 to precipitate inorganic substances which are separated-off together with flocculated or undissolved substances.

Abstract: A process for the production of cellulose from wood and annual plants is provided where the digesting liquor contains free caustic soda, sodium salts of alkyl benzenesulfonic acids, and of aromatic or aliphatic carboxylic acids. By the addition of anthraquinone or its derivatives to the digesting liquor, the delignification is improved. Anthraquinone is resistant to wet oxidation and can be reintroduced into the digesting process. The solubility and, therefore, the effectiveness of anthraquinone is improved by the use of sulfonic acid salts. For the recovery of the digesting chemicals contained in the black liquor, solubilized liquor is precipitated with mineral acid or carbon dioxide and the hemicelluloses are separated by ultra filtration. The resins are separated by extraction with the residual organic compounds, except for the sulfonates and carboxylics, being burned in an aqueous phase with air and/or oxygen.

Abstract: The invention relates to a process for treating a low-concentrated aqueous feed solution which includes at least one aqueous process stream from a pulp mill. The process includes concentrating the feed solution by evaporation to form an evaporation concentrate, and subjecting at least a part of the concentrate to a first electrodialysis treatment, thereby forming a first electrodialysis concentrate containing salt removed from the evaporation concentrate and at least one diluate depleted in the salt. The invention also relates to a plant for carrying out the above process.

Abstract: A method of recovering energy and chemicals from a spent liquor which, after thickening to a dry content of 50-90%, is fed into a reaction chamber (1) in which a plurality of temperature zones are maintained, said method comprising the steps of (a) converting the liquid phase in the spent liquor to a steam phase, (b) thermally decomposing the spent liquor to form gaseous organic substances and solid and/or molten organic and inorganic substances, (c) reducing and (d) oxidizing said substances produced during the thermal decomposition, oxygen or oxygen-containing gas being supplied to the reaction chamber (1) in a controlled amount in order to maintain the reactions, which comprise combustion of organic substances, and a bed of said solid and/or molten substances being formed in a lower temperature zone in the reaction chamber (1). According to the invention said steps are carried out during exposure to low frequency sound.

Abstract: A process and reactor for recovering energy and chemicals from spent liquor obtained in pulp production by thermal decomposing the spent liquor are described, said decomposing being carried out in a reactor at a pressure of from atmospheric pressure up to 150 bar and at a temperature of 500.degree.-1500.degree. C. so that a gas and solid and/or molten inorganic material are formed, said gas being rich in energy to be used as fuel or being useful as raw material for chemical production. According to the invention the thermal decomposition of the spent liquor is carried out during exposure to low frequency sound and without or with simultaneously supply of oxygen or a gas containing oxygen in an amount below that stoichiometrically required for complete oxidation of the substances formed at the thermal decomposition. The reactor comprises at least one sound generator arranged to generate low frequency sound in the reactor.

Abstract: A method for the deinking of recycled fibers, in which the macerated fibers are slurried with water; introduced to a deinking cell which has a central anode and a perimetal cathode; subjected to a direct current electric field applied between the anode and the cathode, causing the ink to be attracted away from the fibers and to electrocoagulate the ink then floating to the surface of the slurry with the aid of gas bubbles generated during the application of the electric field; and washed to recover a cleaner, brighter pulp of recycled fibers.

Abstract: A method for pretreating a cellulosic waste product with microwaves is disclosed as well as a method and apparatus for converting cellulosic wastes into soluble saccharides. The invention greatly enhances a reaction rate for enzymatic hydrolysis. A feed mixture of cellulose, water and acetic acid are irradiated with microwaves at a superatmospheric pressure in an autoclave reaction vessel and the treated cellulose is enzymatically hydrolyzed in a bioreactor. The acid and enzymes are optionally separated for reuse. As a feed stock for the culture of microbes, the sugars can be further processed into ethanol or food protein. High yield, low hazard potential, low energy usage and ready preparation in space of acetic acid and the enzyme makes the present invention well suited for use on long duration space missions.

Abstract: Oxidized weak black liquor or effluents from alkaline bleaching stages, particularly oxygen delignification and/or ozone and/or hydrogen peroxide bleaching effluents are treated in process stages which include an electrolytic cell to recover NaOH, lignin, O.sub.2, H.sub.2 and to achieve other important benefits, the most important of these are (i) to unload the evaporator-recovery furnace and lime-kiln causticizing plant, and (ii) to enable a mill to implement low- or no-chlorine bleaching techniques without overloading their recovery furnace and/or lime kiln or requiring a new, larger recovery system, the electrolytic treatment can be carried out with one or a combination of the above types of effluents; it is also possible to increase the conductivity if required and thus the efficiency of the electrolytic cells and the yield/production of NaOH by the introduction of Na.sub.2 SO.sub.

Abstract: Pretreatment of cellulosic material with carbon dioxide gas, preparatory to being converted chemically, as by hydrolysis, etc. Biomass material, such as branches, stalks, brush, or foliage, or cellulosic products, such as waste paper or cardboard, is reduced to finely divided dry form and is exposed to carbon dioxide in an anhydrous environment, is compressed to superatmospheric pressure and then is decompressed to subatmospheric pressure, expelling air and other gases, particulates, water, other volatiles, etc. Then the cellulosic material is returned to atmospheric pressure, and subsequently is either recycled through such compression and decompression and return, or is compressed to even high pressure. Such environment is enriched in carbon dioxide, such as comprising it in substantial or major part or consisting essentially thereof.

Abstract: A procedure for controlling cellulose digestion by measuring activity of chemicals essentially influencing the cellulose digestion and which are present in a cellulose digester. Feeding of chemicals to be added into the cellulose digester is controlled on the basis of the measurement results. The measurement is carried out by placing, in the cellulose digester, one or several measuring electrodes and reference electrodes, and a current-supplying counterelectrode. Current is supplied to the thus-established circuit from a current source, in a manner such that the voltage across the measuring electrode and the reference electrode, in other words the electrochemical potential of the measuring electrode, is substantially constant. The current intensity corresponding to such potential is directly proportional to activity of the chemicals in the cellulose digester. A method for measuring the cellulose digestive activity is also provided in accordance with the present invention.

Abstract: Wash water input into a pulp washing system is controlled in response to measurements on a stream of output constituents of reduced transverse dimension compared to the transverse dimension of the washed pulp mat discharge stream from the pulp washing system. The measurements are conducted simultaneously across the entire width of the reduced dimension stream on all the washed pulp and water leaving the pulp washing system. The measurements are readily carried out using apparatus including means below said reduced dimension stream.

Abstract: Pulp washing efficiency at any given dilution factor and production rate is maximized by controlling washing surface speed in response to determination of total mass of product stream in weight per unit area on the surface and simultaneously controlling the rate of dilution liquid introduction in response to sensing of feed level in the container feeding the surface, thereby to obtain a substantially constant level of pulp in the feed and in the pulp mat formed on the washing surface which is to undergo washing and a substantially constant weight of pulp mat (on a dry pulp basis) per unit area on the washing surface.

Abstract: A method of rapidly and efficiently treating ligno-cellulosic material for removal of lignin and other non-carbohydrates as well as non-cellulosic carbohydrates from cellulosic matter. Such material is first impregnated with a liquor which is a reaction product obtained by mixing triethyleneglycol with an arylsulfonic or other organic acid. The impregnated material is then rapidly heated by microwaving or application of rf energy to a temperature between about 119 degrees Centigrade to 130 degrees Centigrade and maintained at that temperature for only two to five minutes to reduce the effects of hydrolysis. Thereafter, conventional filtration and washing techniques are applied to achieve a residue material suitable for further use as a wood pulp or for further hydrolysis for the production of organic chemicals.

Abstract: Reductive bleaching of lignin containing pulps employing polydentate ligand complexes of dipositive vanadium, chromium and titanium. High brightness pulps with good reversion stability are obtained. The process is essentially polution free as the reduced complexes can be repeatedly regenerated electrochemically.

Abstract: A batt of non-delignified fibers is stabilized by applying ultrasonic energy thereto in narrow compressed lines which aid in distributing liquid within the batt. The fibers are partially delignified at fiber intersections which are hydrogen bonded. Supplementary stabilization may be provided by thermoplastic bond sites.

Abstract: Reductive bleaching of lignin containing pulps employing polydentate ligand complexes of dipositive vanadium, chromium and titanium. High brightness pulps with good reversion stability are obtained. The process is essentially polution free as the reduced complexes can be repeatedly regenerated electrochemically.