EP2931968A1 - Use of sodium dithionite in a cellulose pulping process - Google Patents

Use of sodium dithionite in a cellulose pulping process

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Publication number
EP2931968A1
EP2931968A1 EP13805310.3A EP13805310A EP2931968A1 EP 2931968 A1 EP2931968 A1 EP 2931968A1 EP 13805310 A EP13805310 A EP 13805310A EP 2931968 A1 EP2931968 A1 EP 2931968A1
Authority
EP
European Patent Office
Prior art keywords
digestion
cooking
acid
salt
range
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Application number
EP13805310.3A
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German (de)
French (fr)
Other versions
EP2931968B1 (en
Inventor
Stefan Erren
Dieter SCHÖNHABER
Martin Schachtl
Steffen Fischer
Christian Baeurich
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BASF SE
Technische Universitaet Dresden
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BASF SE
Technische Universitaet Dresden
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Priority to EP13805310.3A priority Critical patent/EP2931968B1/en
Priority to PL13805310T priority patent/PL2931968T3/en
Publication of EP2931968A1 publication Critical patent/EP2931968A1/en
Application granted granted Critical
Publication of EP2931968B1 publication Critical patent/EP2931968B1/en
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Classifications

    • 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
    • D21C11/00—Regeneration of pulp liquors or effluent waste waters
    • D21C11/06—Treatment of pulp gases; Recovery of the heat content of the gases; Treatment of gases arising from various sources in pulp and paper mills; Regeneration of gaseous SO2, e.g. arising from liquors containing sulfur compounds
    • D21C11/08—Deodorisation ; Elimination of malodorous compounds, e.g. sulfur compounds such as hydrogen sulfide or mercaptans, from gas streams
    • 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
    • D21C3/00—Pulping cellulose-containing materials
    • 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
    • D21C3/00—Pulping cellulose-containing materials
    • D21C3/02—Pulping cellulose-containing materials with inorganic bases or alkaline reacting compounds, e.g. sulfate processes
    • 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
    • D21C3/00—Pulping cellulose-containing materials
    • D21C3/02—Pulping cellulose-containing materials with inorganic bases or alkaline reacting compounds, e.g. sulfate processes
    • D21C3/022—Pulping cellulose-containing materials with inorganic bases or alkaline reacting compounds, e.g. sulfate processes in presence of S-containing compounds
    • 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
    • D21C3/00—Pulping cellulose-containing materials
    • D21C3/04—Pulping cellulose-containing materials with acids, acid salts or acid anhydrides
    • 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
    • D21C3/00—Pulping cellulose-containing materials
    • D21C3/22—Other features of pulping processes
    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
    • D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
    • D21C9/10—Bleaching ; Apparatus therefor
    • D21C9/1084—Bleaching ; Apparatus therefor with reducing compounds
    • D21C9/1089—Bleaching ; Apparatus therefor with reducing compounds with dithionites

Definitions

  • the present invention relates to a process for the production of cellulose from lignocellulosic material by means of sulphite digestion or sulphate pulping, as defined in the claims.
  • cellulose (herein and also referred to in the art as "pulp") from lignocellulosic material, such as wood, are known and described, for example, in U Ilmanns Enzyklopadie der ischen Chemie, 4th Edition, Volume 17, “Paper, Fiber Raw Materials ", Pp. 531-576, Verlag Chemie Weinheim, New York (1979).
  • the cellulose is obtained by chemical digestion processes from the lignocellulosic material, such as wood.
  • chemical digestion methods are, for example, the sulfite pulping used for this purpose or the likewise known sulfate exclusion. Sulphite digestion and sulphate digestion are described, for example, in the above-cited Ullmann literature.
  • lignocellulosic material in both of the above processes is treated as follows to recover cellulose.
  • lignocellulosic material usually wood
  • acidic or neutral medium in the presence of sulphites (salts of sulphurous acid H2SO3)
  • sulphites salts of sulphurous acid H2SO3
  • cooking acid so-called cooking acid
  • magnesium in the form of magnesium oxide (MgO) is used as base which is then converted to dihydrogen sulfite.
  • acidic bisulfite digestion can also cause calcium (Ca), sodium (Na) or Ammonium (NH4) + can be used as a base for the cooking solution, which are then used analogously to magnesium as corresponding oxides or hydroxides.
  • these metals can usually be used analogously, apart from calcium, also in bisulfite digestion.
  • the acid magnesium bisulfite process is the most widely used today.
  • lignocellulosic material usually coniferous wood such as spruce wood, also fir wood and the wood of Hemlocktanne in question.
  • coniferous wood such as spruce wood, also fir wood and the wood of Hemlocktanne in question.
  • deciduous species such as beech, poplar and birch are also suitable.
  • Spruce wood is preferred in the sulphite process.
  • the above-mentioned different types of processes of the sulfite process usually operate at pressures in the range of 0.1 to 10 bar and generally in certain pH ranges.
  • the acid Bisulfitauf gleich a) usually at a pH in the range of 2 to 3
  • the Bisulfitauf gleich b) usually at a pH in the range of 3 to 5
  • the neutral sulphite pulping c) usually at a pH in the range of 6 to 9
  • the alkalisulfite digestion d) usually at a pH of around 1 1.
  • the digestion temperatures differ in the sulfite process.
  • the temperature range of acid Bisulfitauf gleiches a) is usually at 120 ° C to 150 ° C
  • the bisulfite pulping b) usually at 150 ° C to 160 ° C
  • the sodium sulfite pulping c) or even the Alkalisulfitauf gleiches d ) usually at 160 ° C to 180 ° C.
  • the boiling acid of the sulphite process usually contains so-called free sulfur dioxide (SO2), which is present as SO2 and sulphurous acid (hereinafter also "H2SO3") and bound SO2, which is bound to a cation (base) Free SO2 and bound SO2 are in the Generally indicated as total SO 2.
  • the cooking acid of the sulphite process is generally composed as follows: of these, the H2SO3 and the SO2 are assigned to the free SO2 and the M2SO3 to the bound SO2.
  • M is the respective so-called base, example magnesium.
  • the proportion of the base and the SO2 in the cooking acid is given in percent by weight.
  • a cooking acid with a total S02 content of 80 g per liter contains 8% total SO2.
  • the base portion is represented as their respective oxide form such as MgO, CaO, Na 2 O.
  • the preparation of a cooking acid is usually carried out by absorption of SO 2 to water and base carrier.
  • the following equation is intended to serve as an example of the principle of Kochklareher ein the BisulfitaufInstitutes with magnesium as the base (magnesium bisulfite).
  • cellulose is usually made from lignocellulose-containing material, for example, the wood of trees or even of annual plants, for example reeds, grain (straw), sugar cane (bagasse) , Corn won.
  • woodchips of the lignocellulose-containing material for example wood or comminuted plant stems
  • pressure vessels for several hours, for example 3 to 6 hours, at elevated pressure, for example in the range from 7 to 10 bar, usually in a mixture of sodium hydroxide solution (aqueous NaOH ), Sodium sulfide
  • Na 2 S sodium sulfate
  • Na 2 CO 3 optionally sodium carbonate
  • black liquor soluble alkali lignin
  • Cellulose can be separated from lignin with the abovementioned sulphite and sulphate processes, although it is still desirable to increase the pulp yield, in particular while at the same time keeping the lignin content of the pulp low.
  • the kappa number is a measure of the lignin content of the pulp.
  • pulp components
  • pulp mainly hemicelluloses
  • a disadvantage of pulping by the sulphate process is the formation of malodorous substances such as mercaptans, in particular methylmercaptan.
  • the addition of sodium dithionite (hereinafter also "Na 2 S 2 O 4”) in the pulp production process is basically known from the following literature.
  • G. G. Jayme and Woerner describe an alkaline sulfite pulping of spruce wood at 170 ° C, 24 hours, in 100 cm 3 of the digestion solution 3 g NaOH, 1, 56 g of sodium dithionite (Na2S20 4) and 4.69 g of Na2S03 were included.
  • G. Jayme, G. Wörner, paper, Volume 6, Issue 1 1, p 220-222 (1952) In it, relatively large amounts of sodium dithionite, based on the wood to be treated, are described indirectly by means of the quantity of chemicals and the "lye ratio" (p. 221, left-hand column “Zahlentafel" and the subsequent paragraph).
  • the object of the present invention was to obtain a high pulp yield with a simultaneous low lignin content of the pulp in the digestion of lignocellulose-containing material, wherein the formation of malodorous emissions in particular in the sulphate process should be reduced.
  • Lignocellulosic material herein is any material, preferably from nature, containing lignin and cellulose.
  • Preferred lignocellulose-containing material are woods, including shredded woods, such as wood sections from sawmills. Suitable woods are softwoods, preferably spruce or pine or hardwoods such as beech.
  • lignocellulose-containing material is understood here to include grasses and annual plants, for example straw, reed, esparto grass, bamboo and bagasse, these usually not being digested by the sulphite process but preferably by alkaline digestion or the neutral sulphite process.
  • Sulphite pulping and sulphate pulping for the recovery of cellulose are known and are described in the beginning and in more detail in Ullmanns Enzyklopadie der ischen Chemie, 4th Edition, Volume 17, “Paper, Fiber Raw Materials", Verlag Chemie Weinheim, New York (1979) pp. 535-549 in chapter 1.4].
  • Salts of dithionic acid herein are all metal salts or substituted (NFV) or unsubstituted (NhV) ammonium salts of this acid.
  • Highly suitable salts of the dithionic acid are the alkali metal salts, alkaline earth metal salts, salts of the metals of group 12 of the Periodic Table of the Elements, and ammonium (NH 4 + ) salts.
  • Preferred salts of the dithionic acid are sodium dithionite (Na 2 S 2 O 4), potassium dithionite (K 2 S 2 O 4), calcium dithionite (CaS 2 O 4 ), zinc dithionite (ZnS 2 O 4 ), ammonium dithionite ((NhU) C).
  • Salts of dithionic acid including those preferred above, of course also include those individuals containing water of crystallization and / or additives, the latter for example for stabilization.
  • a well-suited dithionic acid salt is the sodium dithionite product, which is marketed by BASF SE as Blankit® or Blankit®S.
  • the digestion temperature in sulfite digestion is usually in the range of 100 ° C to 160 ° C.
  • a suitable sulphite digestion for the process according to the invention is the bisulphite process with Mg (HSC "3) 2 as a component of the cooking acid, which is described in more detail below.
  • Mg HSC "3) 2
  • lignocellulose-containing material coniferous woods, preferably spruce wood, are preferably used as woodchips
  • the amount used is calculated as dry matter (otro), in order to be able to determine, for example, the yield of pulp
  • MgCO-3 "MgCO-3" in the water and then introducing SO 2.
  • the introduction of SO 2 is usually carried out until a clear solution has formed which has a pH value for example, of about 3.8. Usually, approximately the entire dissolved substance is present as Mg (HSO) 2.
  • the pH would continue to decrease as the proportion of sulphurous acid increases.
  • the cooking of the so-called lignocellulosic material with the cooking acid takes place in the usual digesters, discontinuous or continuous. The total cooking time is in the range of 400 to 600 minutes.
  • a temperature profile is used for cooking in the bisulfite process referred to herein, preferably the bisulfite process with Mg (HSOs) 2 as a component of the cooking acid.
  • a well-suited temperature profile is as follows. 1 . Phase: Heating from a temperature in the range of 15 ° C to 30 ° C to a temperature in the range of 100 to 1 10 ° C, within 60 to 120 minutes.
  • 2nd phase Stability for 60 to 90 minutes at a temperature in the range of
  • 3rd phase heating up from a temperature in the range of 100 to 1 10 ° C, up to a temperature in the range of 150 to 160 ° C, within 45 to 90 minutes.
  • 5th phase Cooling to a temperature in the range of 100 to 90 ° C.
  • the salt of dithionous acid preferably sodium dithionite (Na2S20 4) Calciumdithionit (CaS20 4), zinc dithionite (ZnS20 4), particularly preferably sodium dithionite, in the mixture of lignocellulosic material, preferably of wood chips from spruce wood, and the cooking acid, as described above in an amount in the range from 0.1 to 4.0% by weight, preferably from 1.0 to 2.0% by weight, based in each case on the oven-dried lignocellulose-containing material, preferably the oven-dried wood chips from spruce wood.
  • the dosage of the salt of the dithionic acid at any time during the cooking process or before it happen.
  • the following dosage variants are preferred:
  • lignocellulosic material are woods, such as deciduous or preferably coniferous wood, particularly preferably spruce wood, preferably used as wood chips.
  • the mixture known for the sulphate process from sodium hydroxide solution (aqueous NaOH), sodium sulphate (Na 2 S) and sodium sulphate (hereinafter also “Na 2 SO 4") and optionally sodium carbonate (hereinafter also “Na 2 CO 3”), which contains the salt the dithionic acid, preferably selected from the group consisting of sodium dithionite, zinc dithionite, calcium dithionite, in an amount in the range of 0.1 to 4 wt .-% based on the amount of oven-dry lignocellulose-containing material was added.
  • sodium hydroxide solution aqueous NaOH
  • Na 2 S sodium sulphate
  • Na 2 SO 4 sodium sulphate
  • Na 2 CO 3 optionally sodium carbonate
  • the cooking liquor for sulphate pulping usually contains NaOH and sodium sulphide (Na2S) as effective cooking chemicals.
  • NaOH sodium sulphide
  • the necessary concentration of these substances in the cooking liquor is usually dependent on the so-called "liquor ratio.”
  • this liquor ratio is understood as meaning mass fractions of cooking liquor in relation to mass fractions of lignocellulose-containing material, preferably wood (oven-dry (otro)) usually depending on the filling density of wood in the digester, generally in the range from 4: 1 to 4.5: 1, for example 4.2: 1.
  • the concentration of active alkali in the cooking liquor is in the range from 45 to 60 g / l.
  • the content of sodium sulfide (Na2S) in the total effective alkali is the sulfidity (expressed in%). This is usually in the range of 30 to 38%, for example 30%.
  • the cooking liquor for the sulphate process according to the invention contains a salt of the dithionic acid, preferably selected from the group consisting of sodium dithionite, zinc dithionite, calcium dithionite, in an amount in the range from 0.1 to 4% by weight, based on the amount of oven-dried lignocellulose-containing Material.
  • a salt of the dithionic acid preferably selected from the group consisting of sodium dithionite, zinc dithionite, calcium dithionite, in an amount in the range from 0.1 to 4% by weight, based on the amount of oven-dried lignocellulose-containing Material.
  • the pH of the cooking liquor for the sulphate process according to the invention is usually about 14 at the beginning of the cooking process.
  • the cooking of the lignocellulosic material with the cooking liquor for the sulfate process according to the invention takes place in the usual digesters discontinuous or continuous.
  • the total cooking time for the sulfate process of the invention is usually in the range of 200 to 400 minutes, preferably 240 to 300 minutes.
  • the boiling temperature for the sulfate process of the invention is in the range of 160 to 185 ° C, for example at 170 ° C.
  • the salt of the dithionic acid preferably selected from the group consisting of sodium dithionite, zinc dithionite, calcium dithionite, more preferably sodium dithionite, is used in the sulphate process of the invention for mixing the lignocellulosic material and the cooking liquor in an amount ranging from 0.1 to 4.0 wt. %, preferably 1.0 to 2.0% by weight, based in each case on the oven-dried lignocellulose-containing material.
  • the dosage of the salt of the dithionic acid can be done at any time during the cooking process of the sulphate process according to the invention.
  • the salt of the dithionic acid is preferably added in the impregnation phase, the final phase of the digestion or in the main phase of the digestion of the sulphate process according to the invention, particularly preferably in the final phase of the digestion or in the main phase of the digestion of the sulphate process according to the invention.
  • the process according to the invention for the production of cellulose from lignocellulose-containing material by means of sulfite pulping or sulfate pulping produces pulp in good yield with good delignification of the lignocellulose-containing material. The whiteness of the unbleached pulp is improved.
  • the addition of a salt of the dithionic acid in the sulfate process of the invention reduces the concentration of malodorous substances, preferably mercaptans in the exhaust gas of the sulfate cooking process. Examples
  • Spruce wood chips pre-sorted and pre-dried in the room air for 2 to 3 days before cooking water content in the range of 23.4 to 33.2 wt .-%, on average about 30 wt .-%
  • 3200 g (oven-dry (otro) calculated) spruce chips with an original water content as described in A) and 16 liters of the cooking acid from B) were filled in the discontinuous cooker with a capacity of 25 liters, according to a quantitative ratio of cooking acid: otro wood of 5: 1.
  • the cooker had an acid circulation and electric jacket heating as well as a temperature controller, manometer, temperature sensor and pH electrode, as well as connected EDP system.
  • 3rd phase 60 min heating-up time from 105 ° C to final cooking temperature 155 ° C
  • the total digestion time was 510 min (8 h 30 min).
  • the pressure in the digester was 8 to 9 bar at the end of the final cooking time.
  • Sodium dithionite (Blankit®S from BASF SE) was dissolved in water by metering pump within 10 min in the digester added to the mixture and that 32 g of pure Na2S20 4 (1 wt .-% Na2S20 4 based on otro counted wood used) or 64 g pure Na2S20 4 (2 wt .-% Na2S20 4 based on used otro counted wood).
  • Sodium dithionite addition times were, per experiment, as follows:
  • experiment W 16 the chips were impregnated immediately before digestion with such an amount of aqueous solution of sodium dithionite (Blankit®S BASF SE), corresponding to 1 wt .-% pure Na 2 S 20 4 based on otro computed timber used.
  • the pulp was removed, mixed with water and defibered with a stirrer. The shredded pulp was filled into a sieve, washed with water and dehydrated in a centrifuge.
  • Acceptance of raw material means amount of pulp received (without coarse or splinter content) in relation to the wood used; It was determined by weighing and dry content measurement.
  • the kappa number indicates the hardness of the pulp and was determined in accordance with ISO 302. Put simply, when determining the kappa number in an aqueous pulp suspension in an acidic medium under defined conditions, the potassium permanganate consumption (KMnCM consumption) is measured. The higher the lignin content in the pulp, the higher the consumption of potassium permanganate and thus the kappa number. The higher the kappa number, the higher the residual lignin content of the pulp, the harder is the pulp in general.
  • Whiteness means remission at 457 nm and was determined on the Datacolor Elrepho® instrument according to ISO 2470.
  • the viscosity determination was carried out according to ISO 5351/1 (International Standard ISO 5351/1, Cellulose in dilute Solutions - Determination of liming viscosity number, Part 1: Method in cupri-ethylene-diamine (CED) Solution, First edition 1981 -12 -01).
  • ISO 5351/1 International Standard ISO 5351/1, Cellulose in dilute Solutions - Determination of liming viscosity number, Part 1: Method in cupri-ethylene-diamine (CED) Solution, First edition 1981 -12 -01.
  • a solution of cellulose in copper ethylenediamine solution is prepared.
  • the concentration of the solvent is fixed.
  • the concentration of cellulose in the solution should be determined according to the sample used in the determination.
  • the throughput time of both the solvent and the cellulose solution is measured by a capillary viscometer at 25 ° C.
  • the calculation of the intrinsic viscosity is based on the results of the determination and the known concentration of the cellulose solution according to the Martin equation.
  • the measurement was carried out according to the alternative A of the determination method (International Standard ISO 5351/1, Cellulose in dilute Solutions - Determination of liming viscosity number, Part 1: Method in cupri-ethylene-diamine (CED) Solution, First edition 1981 -12 -01). It is carried out at low cellulose concentration and used for the measurement of the transit times of solvent and cellulose solution, the same capillary.
  • Lignocellulose-containing material A) Lignocellulose-containing material:
  • the cooking liquor was prepared by adding commercial laboratory chemicals in water from caustic soda (NaOH) and sodium sulfide (Na2S). The amount of chemicals used was calculated so that an alkali ratio of 23% was used at a sulphidity of 20%.
  • Table 4 shows the yield of the accepts and the kappa number. Table 4: Cooking No. Auxiliary agent addition [1] Acceptance of raw material% Kappa number
  • Acceptance yield and kappa number are as defined under (I) above.
  • exhaust gases gases from the digester
  • exhaust samples were taken at different times with a tracer pump
  • concentration of methylmercaptan in these samples was measured with methylmercaptan-specific gas detector tubes.
  • the methylmercaptan concentration is highest.
  • the use of Na2S20 4 leads to a decrease of the methyl mercatane in the exhaust gas.

Abstract

The invention relates to a method for producing cellulose from material containing lignocellulose by means of sulfite decomposition or sulfate decomposition in the presence of a salt of dithionous acid, characterized in that the salt of dithionous acid is used in an amount in the range of 0.1 to 4.0 wt% with respect to the amount of kiln-dry material containing lignocellulose.

Description

Verwendung von Natriumdithionit im Zellstoffkochprozess Beschreibung Die vorliegende Erfindung betrifft ein Verfahren zur Herstellung von Zellulose aus lignocellulo- sehaltigem Material mittels Sulfitaufschluss oder Sulfataufschluss, wie in den Ansprüchen defi- niert.  Description: The present invention relates to a process for the production of cellulose from lignocellulosic material by means of sulphite digestion or sulphate pulping, as defined in the claims.
Die Verfahren zur Gewinnung von Zellulose (hierin und in der Fachwelt auch„Zellstoff" ge- nannt) aus lignocellulosehaltigem Material, wie Holz, sind bekannt und beispielsweise in U Ilmanns Enzyklopädie der technischen Chemie, 4. Auflage, Band 17,„Papier, Faserrohsstoffe", S. 531 -576, Verlag Chemie Weinheim, New York (1979), beschrieben. Üblicherweise wird die Zellulose durch chemische Aufschlussprozesse aus dem lignocellulosehaltigen Material, beispielsweise Holz, gewonnen. Solche chemischen Aufschlussverfahren sind beispielsweise der für diese Zwecke angewendeter Sulfitaufschluss oder der ebenfalls bekannte Sulfatauschluss. Sulfitaufschluss und Sulfataufschluss sind zum Beispiel in der oben zitierten Ullmann-Literatur beschrieben. The processes for recovering cellulose (herein and also referred to in the art as "pulp") from lignocellulosic material, such as wood, are known and described, for example, in U Ilmanns Enzyklopadie der technischen Chemie, 4th Edition, Volume 17, "Paper, Fiber Raw Materials ", Pp. 531-576, Verlag Chemie Weinheim, New York (1979). Usually, the cellulose is obtained by chemical digestion processes from the lignocellulosic material, such as wood. Such chemical digestion methods are, for example, the sulfite pulping used for this purpose or the likewise known sulfate exclusion. Sulphite digestion and sulphate digestion are described, for example, in the above-cited Ullmann literature.
Vereinfacht gesagt wird lignocellulosehaltiges Material in beiden oben genannten Prozessen wie folgt behandelt um Zellulose zu gewinnen. Put simply, lignocellulosic material in both of the above processes is treated as follows to recover cellulose.
Beim Sulfitverfahren (hierin auch„Sulfitaufschluss" genannt) wird lignocellulosehaltiges Material, üblicherweise Holz, im sauren oder neutralen Milieu in Gegenwart von Sulfiten (Salze der schwefligen Säure H2SO3) mit einer sogenannten Kochsäure behandelt, wobei das Lignin übli- cherweise sulfoniert und wasserlöslich wird und somit aus den Fasern entfernt werden kann unter Zurücklassen des Zellstoffes. In the sulphite process (also referred to herein as "sulphite digestion"), lignocellulosic material, usually wood, in acidic or neutral medium in the presence of sulphites (salts of sulphurous acid H2SO3) is treated with a so-called cooking acid, the lignin usually becoming sulphonated and water soluble and thus can be removed from the fibers leaving the pulp.
Es existieren diverse Prozess-Typen des Sulfitaufschlusses, die sich unter anderem durch den pH-Wert ihrer Kochlösung unterscheiden. Dies sind beispielsweise: a) Der saure Bisulfitaufschluss mit Magnesiumdihydrogensulfit (im folgenden auch „Mg(HS03)2" ) und Schwefeldioxid, SO2 sowie Wasser als Komponente der Kochsäure, There are various process types of sulfite pulping, which differ, inter alia, by the pH of their cooking solution. These are, for example: a) the acid bisulfite digestion with magnesium dihydrogen sulfite (hereinafter also "Mg (HSO) 2") and sulfur dioxide, SO 2 and water as component of the cooking acid,
b) der Bisulfitaufschluss mit Mg(HSC"3)2, als Komponente der Kochsäure, c) der Neutralsulfitaufschluss mit Dinatriumsulfit (im folgenden auch ,,Na2S03-) und Natriumcarbonat (im folgenden auch„ Na2C03"), als Komponenten der Kochsäure und  b) the Bisulfitaufschluss with Mg (HSC "3) 2, as a component of the cooking acid, c) the neutral sulphite pulping with disodium sulphite (hereinafter also ,, Na2S03-) and sodium carbonate (hereinafter also" Na2C03 "), as components of the cooking acid and
d) der Alkalisulfitaufschluss mit Na2S03 und Natriumhydroxid (im folgenden auch „NaOH") sowie Wasser als Komponten der Kochsäure.  d) the Alkalisulfitaufschluss with Na2S03 and sodium hydroxide (hereinafter also "NaOH") and water as components of the cooking acid.
In der Regel wird beim sauren Bisulfitaufschluss Magnesium in Form von Magnesiumoxid (MgO) als Base verwendet welches dann zum Dihydrogensulfit umgesetzt wird. Anstelle des Magnesiums (Mg) kann beim sauren Bisulfitaufschluss auch Calcium (Ca), Natrium (Na) oder Ammonium (NH4)+ als Base für die Kochlösung verwendet werden, welches dann analog Magnesium als entsprechende Oxide bzw. Hydroxide eingesetzt werden. Ebenso können diese Metalle üblicherweise, bis auf Calcium, auch beim Bisulfitaufschluss analog eingesetzt werden. Beim Sulfitverfahren ist heute das saure Magnesiumbisulfitverfahren das am häufigsten angewendete. As a rule, in the case of acidic bisulfite pulping, magnesium in the form of magnesium oxide (MgO) is used as base which is then converted to dihydrogen sulfite. In place of magnesium (Mg), acidic bisulfite digestion can also cause calcium (Ca), sodium (Na) or Ammonium (NH4) + can be used as a base for the cooking solution, which are then used analogously to magnesium as corresponding oxides or hydroxides. Likewise, these metals can usually be used analogously, apart from calcium, also in bisulfite digestion. In the sulfite process, the acid magnesium bisulfite process is the most widely used today.
Für das Sulfitverfahren kommen als lignocellulosehaltiges Material in der Regel Nadelhölzer wie Fichtenholz, zudem Tannenholz und das Holz der Hemlocktanne in Frage. Überdies eig- nen sich auch einige Laubholzarten wie Buche, Pappel und Birke. Bevorzugt im Sulfitverfahren ist Fichtenholz. For the sulfite process come as a lignocellulosic material usually coniferous wood such as spruce wood, also fir wood and the wood of Hemlocktanne in question. In addition, some deciduous species such as beech, poplar and birch are also suitable. Spruce wood is preferred in the sulphite process.
Die oben genannten verschiedenen Prozesstypen des Sulfitverfahrens arbeiten üblicherweise jeweils bei Drücken im Bereich von 0,1 bis 10 bar und im Allgemeinen bei bestimmten pH- Wertbereichen. Der saure Bisulfitaufschluss a) üblicherweise bei einem pH-Wert im Bereich von 2 bis 3, der Bisulfitaufschluss b) üblicherweise bei einem pH-Wert im Bereich von 3 bis 5, der Neutralsulfitaufschluss c) üblicherweise bei einem pH-Wert im Bereich von 6 bis 9 und der Alka- lisulfitaufschluss d) üblicherweise bei einem pH-Wert um 1 1. Entsprechend des pH-Bereiches unterscheiden sich die Aufschlusstemperaturen beim Sulfitverfahren. So liegt der Temperaturbereich des sauren Bisulfitaufschlusses a) in der Regel bei 120 °C bis 150 °C, der des Bisulfitaufschlusses b) in der Regel bei 150 °C bis 160 °C und der des Natriumsulfitaufschlusses c) bzw. auch der des Alkalisulfitaufschlusses d) in der Regel bei 160 °C bis 180 °C. The above-mentioned different types of processes of the sulfite process usually operate at pressures in the range of 0.1 to 10 bar and generally in certain pH ranges. The acid Bisulfitaufschluss a) usually at a pH in the range of 2 to 3, the Bisulfitaufschluss b) usually at a pH in the range of 3 to 5, the neutral sulphite pulping c) usually at a pH in the range of 6 to 9 and the alkalisulfite digestion d) usually at a pH of around 1 1. Depending on the pH range, the digestion temperatures differ in the sulfite process. Thus, the temperature range of acid Bisulfitaufschlusses a) is usually at 120 ° C to 150 ° C, the bisulfite pulping b) usually at 150 ° C to 160 ° C and the sodium sulfite pulping c) or even the Alkalisulfitaufschlusses d ) usually at 160 ° C to 180 ° C.
Die Kochsäure des Sulfitverfahrens enthält üblicherweise sogenanntes freies Schwefeldioxid (SO2), das als SO2 und schweflige Säure (im folgenden auch„H2SO3") vorliegt und gebundenes SO2, welches an ein Kation (Base) gebunden ist. Freies SO2 und gebundenes SO2 werden in der Regel als Gesamt-S02 angegeben. Die Kochsäure des Sulfitverfahrens setzt sich im Allge- meinen folgendermaßen zusammen: davon werden das H2SO3 und das SO2 dem freien SO2 und das M2SO3 dem gebundenen SO2 zugeordnet. M ist hier die jeweilige sogenannte Base, Beispiel Magnesium. The boiling acid of the sulphite process usually contains so-called free sulfur dioxide (SO2), which is present as SO2 and sulphurous acid (hereinafter also "H2SO3") and bound SO2, which is bound to a cation (base) Free SO2 and bound SO2 are in the Generally indicated as total SO 2. The cooking acid of the sulphite process is generally composed as follows: of these, the H2SO3 and the SO2 are assigned to the free SO2 and the M2SO3 to the bound SO2. M here is the respective so-called base, example magnesium.
Der Anteil der Base und des SO2 in der Kochsäure wird dabei in Gewichts-Prozent angegeben. So enthält beispielsweise eine Kochsäure mit einem Gehalt an Gesamt-S02 von 80 g pro Liter 8 % Gesamt- SO2. Der Base-Anteil wird als deren jeweilige Oxid-Form wiedergegeben wie MgO, CaO, Na20. Die Herstellung einer Kochsäure erfolgt üblicherweise durch eine Absorption von SO2 an Wasser und Basenträger. Die nachstehende Gleichung soll als Beispiel für das Prinzip der Kochsäureherstellung des Bisulfitaufschlusses mit Magnesium als Base (Magnesiumbisulfit) dienen. Mg(OH)2 + 2 S02 -» Mg(HS03)2 The proportion of the base and the SO2 in the cooking acid is given in percent by weight. For example, a cooking acid with a total S02 content of 80 g per liter contains 8% total SO2. The base portion is represented as their respective oxide form such as MgO, CaO, Na 2 O. The preparation of a cooking acid is usually carried out by absorption of SO 2 to water and base carrier. The following equation is intended to serve as an example of the principle of Kochsäureherstellung the Bisulfitaufschlusses with magnesium as the base (magnesium bisulfite). Mg (OH) 2 + 2 S0 2 -> Mg (HSO 3 ) 2
Im Sulfatverfahren (auch als„Kraft-Aufschluss" oder„Sulfataufschluß" in der Fachwelt bezeichnet) wird Zellulose üblicherweise aus lignocellulosehaltigem Material beispielsweise dem Holz von Bäumen oder auch aus einjährigen Pflanzen, beispielsweise Schilf, Getreide (Stroh), Zu- ckerrohr (Bagasse), Mais gewonnen. In the sulphate process (also referred to as "power digestion" or "sulphate digestion" in the professional world) cellulose is usually made from lignocellulose-containing material, for example, the wood of trees or even of annual plants, for example reeds, grain (straw), sugar cane (bagasse) , Corn won.
Üblicherweise erhitzt man im Sulfatverfahren Hackschnitzel des lignocellulosehaltigen Materials, beispielsweise Holz oder zerkleinerte Pflanzenstängel, in Druckkesseln mehrere Stunden, beispielsweise 3 bis 6 Stunden, lang bei erhöhtem Druck, beispielsweise im Bereich von 7 bis 10 bar, üblicherweise in einem Gemisch aus Natronlauge (wässrige NaOH), NatriumsulfidIn the sulfate process, woodchips of the lignocellulose-containing material, for example wood or comminuted plant stems, are usually heated in pressure vessels for several hours, for example 3 to 6 hours, at elevated pressure, for example in the range from 7 to 10 bar, usually in a mixture of sodium hydroxide solution (aqueous NaOH ), Sodium sulfide
(Na2S), und Natriumsulfat (im folgenden auch„Na2S04") und gegebenenfalls Natriumcarbonat (im folgenden auch„Na2C03") . (Na 2 S), and sodium sulfate (hereinafter also "Na 2 SO 4") and optionally sodium carbonate (hereinafter also "Na 2 CO 3").
Hierbei entsteht die sogenannte„Schwarzlauge" (lösliches Alkali-Lignin), die über Filtration vom Zellstoff abgetrennt wird. This results in the so-called "black liquor" (soluble alkali lignin), which is separated by filtration from the pulp.
Mit den genannten Sulfit- und Sulfatverfahren lässt sich Zellulose von Lignin abtrennen, allerdings ist es nach wie vor wünschenswert die Zellstoffausbeute zu erhöhen und dies insbesondere bei gleichzeitigem niedrigen Ligningehalt des Zellstoffs. Cellulose can be separated from lignin with the abovementioned sulphite and sulphate processes, although it is still desirable to increase the pulp yield, in particular while at the same time keeping the lignin content of the pulp low.
Es ist bekannt, dass es beispielsweise beim Aufschluss von Holz zu Zellstoff einen Zusammenhang gibt zwischen dem sogenannten„Aufschlussgrad", ausgedrückt zum Beispiel durch die „Kappa-Zahl", und der Zellstoffausbeute. It is known that, for example, in the pulping of wood to pulp there is a connection between the so-called "degree of pulping", expressed for example by the "kappa number", and the pulp yield.
Die Kappa-Zahl ist ein Maß für den Ligningehalt des Zellstoffes. The kappa number is a measure of the lignin content of the pulp.
Eine sehr niedrige Kappa-Zahl, also sehr niedriger Ligningehalt im Zellstoff, korreliert üblicherweise mit einer niedrigen Zellstoff ausbeute. Üblicherweise wird nämlich bei fortschreitendem Aufschluss nicht nur das Lignin mehr und mehr entfernt, sondern zunehmend auch Zellstoff (komponenten) (vorwiegend Hemicellulosen) aus dem Holz in die Kochsäure oder Kochlauge herausgelöst. Daraus resultiert eine geringere Menge an isoliertem Zellstoff relativ zum eingesetzten Holz. A very low kappa number, ie very low lignin content in the pulp, usually correlates with a low pulp yield. Usually, namely, with progressive digestion not only the lignin more and more removed, but increasingly also pulp (components) (mainly hemicelluloses) dissolved out of the wood in the cooking acid or cooking liquor. This results in a lower amount of isolated pulp relative to the wood used.
Ein Nachteil des Zellstoffaufschlusses nach dem Sulfatverfahren ist die Entstehung von übelriechenden Stoffen wie Mercaptanen, insbesondere Methylmercaptan. Der Zusatz von Natriumdithionit (im folgenden auch„Na2S204") beim Zellstoffherstellungspro- zess ist grundsätzlich aus der folgenden Literatur bekannt. G. Jayme und G. Wörner beschreiben einen alkalischen Sulfitaufschluss von Fichtenholz bei 170 °C, 24 Stunden, wobei in 100 cm3 der Aufschlusslösung 3 g NaOH, 1 ,56 g Natriumdithionit (Na2S204) und 4,69 g Na2S03 enthalten waren. (G. Jayme, G. Wörner, Papier, 6. Jahrgang, Heft 1 1 , S. 220-222 (1952)). Darin werden relativ große Mengen Natriumdithionit bezogen auf das zu behandelnde Holz indirekt über die Mengenaufstellung der Chemikalien sowie das„Laugenverhältnis" beschrieben (S. 221 , linke Spalte Zahlentafel und der sich daran anschließende Absatz). A disadvantage of pulping by the sulphate process is the formation of malodorous substances such as mercaptans, in particular methylmercaptan. The addition of sodium dithionite (hereinafter also "Na 2 S 2 O 4") in the pulp production process is basically known from the following literature. G. G. Jayme and Woerner describe an alkaline sulfite pulping of spruce wood at 170 ° C, 24 hours, in 100 cm 3 of the digestion solution 3 g NaOH, 1, 56 g of sodium dithionite (Na2S20 4) and 4.69 g of Na2S03 were included. (G. Jayme, G. Wörner, paper, Volume 6, Issue 1 1, p 220-222 (1952)). In it, relatively large amounts of sodium dithionite, based on the wood to be treated, are described indirectly by means of the quantity of chemicals and the "lye ratio" (p. 221, left-hand column "Zahlentafel" and the subsequent paragraph).
Weiterhin beschreiben Jayme und Wörner in Holz als Roh- und Werkstoff 10 (1952) 6, S. 244- 249, die Verwendung relativ großer Mengen von Natriumdithionit (Na2S204) in einer Sulfatlauge (65% NaOH, 25% Na2S und 10% Na2C03) beim Sulfataufschluss von Fichtenholz. Die Menge Natriumdithionit bezogen auf das zu behandelnde Holz ist auch hier indirekt über die Mengenaufstellung der Chemikalien sowie das„Laugenverhältnis" beschrieben (S. 246, linke Spalte ab„Wirkung des Natriumhypodisulfits in Sulfataufschlußlösungen" bis inclusive Tabelle 2). Das dort beschreibene„Laugenverhältnis" von 1 : 7,5 besagt, dass auf 1 Massenteil Holz 7,5 Massenteile Kochlauge eingesetzt wurden. Furthermore, Jayme and Wörner in Holz as Roh- und Werkstoff 10 (1952) 6, pp. 244-249, describe the use of relatively large amounts of sodium dithionite (Na 2 SO 4 ) in a sulphate liquor (65% NaOH, 25% Na 2 S and 10 % Na 2 C0 3 ) in sulphate pulping of spruce wood. The amount of sodium dithionite, based on the wood to be treated, is also described here indirectly via the quantitative preparation of the chemicals and the "alkali ratio" (page 246, left-hand column from "effect of the sodium hypodisulfite in sulphate digestion solutions" up to and including Table 2). The "lye ratio" of 1: 7.5 described there indicates that 7.5 parts by mass of cooking liquor were used for 1 part by mass of wood.
Aufgabe der vorliegenden Erfindung war es eine hohe Zellstoff ausbeute bei gleichzeitigem geringen Ligningehalt des Zellstoffs beim Aufschluss von lignocellulosehaltigem Material zu erhal- ten, wobei insbesondere beim Sulfatverfahren die Entstehung übelriechender Emissionen vermindert werden soll. The object of the present invention was to obtain a high pulp yield with a simultaneous low lignin content of the pulp in the digestion of lignocellulose-containing material, wherein the formation of malodorous emissions in particular in the sulphate process should be reduced.
Die Aufgabe wurde gelöst in dem man bei dem Sulfitaufschluss oder Sulfatausschluss geringe Mengen eines Salzen der dithionigen Säure (diese im folgenden auch„H2S2O4") zusetzt und wie im übrigen in den Ansprüchen beschrieben. The object was achieved by adding small amounts of a salt of the dithionic acid (hereinafter also "H 2 S 2 O 4") in the sulfite pulping or sulfate exclusion and as described in the other claims.
Zellulose ist bekannt und beispielsweise in„Ullmanns Enzyklopädie der technischen Chemie, 4. Auflage, Band 17,„Papier, Faserrohsstoffe", Verlag Chemie Weinheim, New York (1979) S. 531 -532 in Kapitel 1 " beschrieben. Lignocellulosehaltiges Material ist hierin jegliches Material, vorzugsweise aus der Natur, welches Lignin und Zellulose enthält. Cellulose is known and described for example in "Ullmann's Encyclopedia of Industrial Chemistry, 4th Edition, Volume 17," Paper, Faserrohsstoffe ", Verlag Chemie Weinheim, New York (1979) pp 531 -532 in Chapter 1". Lignocellulosic material herein is any material, preferably from nature, containing lignin and cellulose.
Bevorzugtes lignocellulosehaltiges Material sind Hölzer, inklusive zerkleinerte Hölzer, wie Holzabschnitte aus Sägewerken. Gut geeignete Hölzer sind Nadelhölzer, vorzugsweise Fichte oder Kiefer oder Laubhölzer wie Buche. Preferred lignocellulose-containing material are woods, including shredded woods, such as wood sections from sawmills. Suitable woods are softwoods, preferably spruce or pine or hardwoods such as beech.
Weiterhin werden hierin unter lignocellulosehaltigem Material noch Gräser und Einjahrespflan- zen, beispielsweise Stroh, Schilf, Espartogras, Bambus und Bagasse verstanden, wobei diese üblicherweise nicht mit dem Sulfitverfahren aufgeschlossen werden, sondern vorzugsweise mit alkalischen Aufschlussverfahren oder dem Neutralsulfitverfahren. Der Sulfitaufschluss und der Sulfataufschluss zur Gewinnung von Zellulose sind bekannt und werden eingangs und ausführlicher in Ullmanns Enzyklopädie der technischen Chemie, 4. Auflage, Band 17,„Papier, Faserrohsstoffe", Verlag Chemie Weinheim, New York (1979)S. 535- 549 in Kapitel 1.4] beschrieben. Furthermore, lignocellulose-containing material is understood here to include grasses and annual plants, for example straw, reed, esparto grass, bamboo and bagasse, these usually not being digested by the sulphite process but preferably by alkaline digestion or the neutral sulphite process. Sulphite pulping and sulphate pulping for the recovery of cellulose are known and are described in the beginning and in more detail in Ullmanns Enzyklopadie der technischen Chemie, 4th Edition, Volume 17, "Paper, Fiber Raw Materials", Verlag Chemie Weinheim, New York (1979) pp. 535-549 in chapter 1.4].
Salze der dithionigen Säure (H2S2O4) sind hierin alle Metallsalze oder substituierten (NFV) oder unsubstituierten (NhV) Ammoniumsalze dieser Säure. Salts of dithionic acid (H2S2O4) herein are all metal salts or substituted (NFV) or unsubstituted (NhV) ammonium salts of this acid.
Gut geeignete Salze der dithionigen Säure sind die Alkalimetallsalze, Erdalkalimetallsalze, Sal- ze der Metalle der Gruppe 12 des Periodensystems der Elemente, sowie Ammonium (NH4 +)- Salze. Highly suitable salts of the dithionic acid are the alkali metal salts, alkaline earth metal salts, salts of the metals of group 12 of the Periodic Table of the Elements, and ammonium (NH 4 + ) salts.
Bevorzugte Salze der dithionigen Säure sind Natriumdithionit (Na2S204), Kaliumdithionit (K2S2O4), Calciumdithionit (CaS204), Zinkdithionit (ZnS204), Ammoniumdithionit ((NhU^C ). Preferred salts of the dithionic acid are sodium dithionite (Na 2 S 2 O 4), potassium dithionite (K 2 S 2 O 4), calcium dithionite (CaS 2 O 4 ), zinc dithionite (ZnS 2 O 4 ), ammonium dithionite ((NhU) C).
Salze der dithionigen Säure, inklusive der oben bevorzugten, umfassen selbstverständlich auch jene Individuen, welche Kristallwasser und/oder Additive, letztere beispielsweise zum Stabilisieren, enthalten. Ein gut geeignetes Salz der dithionigen Säure ist das Natriumdithionit-Produkt, welches von BASF SE als Blankit® oder Blankit®S in den Handel gebracht wird. Salts of dithionic acid, including those preferred above, of course also include those individuals containing water of crystallization and / or additives, the latter for example for stabilization. A well-suited dithionic acid salt is the sodium dithionite product, which is marketed by BASF SE as Blankit® or Blankit®S.
Für das erfindungsgemäße Verfahren sind grundsätzlich alle Varianten des Suflitaufschlusses, wie eingangs und in Ullmanns Enzyklopädie der technischen Chemie, 4. Auflage, Band 17, „Papier, Faserrohsstoffe", S. 531 -576, Verlag Chemie Weinheim, New York (1979)beschrieben, geeignet. For the inventive method are basically all variants of Suflitaufschlusses, as described in the beginning and in Ullmann's Encyclopedia of Industrial Chemistry, 4th Edition, Volume 17, "Paper, Faserrohsstoffe", pp 531 -576, Verlag Chemie Weinheim, New York (1979) , suitable.
Die Aufschlußtemperatur beim Sulfitaufschluß liegt üblicherweise im Bereich von 100 °C bis 160 °C. The digestion temperature in sulfite digestion is usually in the range of 100 ° C to 160 ° C.
Ein für das erfindungsgemäße Verfahren gut geeigneter Sulfitaufschluss ist das Bisulfitverfah- ren mit Mg(HSC"3)2 als Komponente der Kochsäure, welches im Folgenden näher beschrieben wird. Als lignocellulosehaltiges Material werden Nadelhölzer, vorzugsweise Fichtenhölzer, bevorzugt als Hackschnitzel eingesetzt. Die Hackschnitzel werden üblicherweise waldfrisch (also mit einem Trockengehalt von etwa 50 Gew.-%) eingesetzt. Die Einsatzmenge wird als Trockensubstanz (otro) errechnet, um dann beispielsweise die Ausbeute an Zellstoff bestimmen zu können. Die Kochsäure kann durch Aufschlämmen von Magnesiumcarbonat (im folgenden auchA suitable sulphite digestion for the process according to the invention is the bisulphite process with Mg (HSC "3) 2 as a component of the cooking acid, which is described in more detail below.As lignocellulose-containing material, coniferous woods, preferably spruce wood, are preferably used as woodchips The amount used is calculated as dry matter (otro), in order to be able to determine, for example, the yield of pulp
„MgCO-3") im Wasser und anschließendes Einleitens von SO2 hergestellt werden. Die Einleitung von SO2 erfolgt in der Regel solange, bis eine klare Lösung entstanden ist, die einen pH-Wert beispielsweise von etwa 3,8 aufweist. Dabei liegt üblicherweise etwa die gesamte gelöste Substanz als Mg(HS03)2 vor. Bei weiterer Einleitung von SO2 würde der pH-Wert mit zunehmendem Anteil an schwefliger Säure weiter sinken. Die Kochung des sogenannten lignocellulosehaltigen Materials mit der Kochsäure findet in den üblichen Kochern, diskontinuierlich oder auch kontinuierlich statt. Die Gesamtkochzeit liegt im Bereich von 400 bis 600 Minuten. "MgCO-3") in the water and then introducing SO 2. The introduction of SO 2 is usually carried out until a clear solution has formed which has a pH value for example, of about 3.8. Usually, approximately the entire dissolved substance is present as Mg (HSO) 2. Upon further introduction of SO2, the pH would continue to decrease as the proportion of sulphurous acid increases. The cooking of the so-called lignocellulosic material with the cooking acid takes place in the usual digesters, discontinuous or continuous. The total cooking time is in the range of 400 to 600 minutes.
Vorzugsweise wird für die Kochung in den hierin genannten Bisulfitverfahren, vorzugsweise dem Bisulfitverfahren mit Mg(HSOs)2 als Komponente der Kochsäure, ein Temperaturprofil verwendet. Preferably, a temperature profile is used for cooking in the bisulfite process referred to herein, preferably the bisulfite process with Mg (HSOs) 2 as a component of the cooking acid.
Ein gut geeignetes Temperaturprofil ist wie folgt. 1 . Phase: Aufheizung von einer Temperatur im Bereich von 15 °C bis 30 °C auf eine Temperatur im Bereich von 100 bis 1 10 °C, innerhalb von 60 bis 120 Minuten. A well-suited temperature profile is as follows. 1 . Phase: Heating from a temperature in the range of 15 ° C to 30 ° C to a temperature in the range of 100 to 1 10 ° C, within 60 to 120 minutes.
2. Phase (Imprägnierphase): 60 bis 90 Minuten Verharren bei einer Temperatur im Bereich von 2nd phase (impregnation phase): Stability for 60 to 90 minutes at a temperature in the range of
100 bis 1 10 °C.  100 to 1 10 ° C.
3. Phase: Hochheizen von einer Temperatur im Bereich von 100 bis 1 10 °C, bis zu einer Temperatur im Bereich von 150 bis 160 °C, innerhalb von 45 bis 90 Minuten. 3rd phase: heating up from a temperature in the range of 100 to 1 10 ° C, up to a temperature in the range of 150 to 160 ° C, within 45 to 90 minutes.
4. Phase (Fertigkochzeit): 150 bis 250 Minuten verharren bei einer Temperatur im Bereich von 150 bis 160°C 4th phase (final cooking time): 150 to 250 minutes remain at a temperature in the range of 150 to 160 ° C
5. Phase: Abkühlung auf eine Temperatur im Bereich von 100 bis 90 °C. 5th phase: Cooling to a temperature in the range of 100 to 90 ° C.
Das Salz der dithionigen Säure, vorzugsweise Natriumdithionit (Na2S204), Calciumdithionit (CaS204), Zinkdithionit (ZnS204), besonders bevorzugt Natriumdithionit, wird in die Mischung aus lignocellulosehaltigen Material, vorzugsweise der Hackschnitzel aus Fichtenholz, und der Kochsäure, wie oben beschrieben in einer Menge im Bereich von 0,1 bis 4,0 Gew.- %, vor- zugsweise 1 ,0 bis 2,0 Gew.- %, jeweils bezogen auf das ofentrockene lignocellulosehaltige Material, vorzugsweise den ofentrockenen Hackschnitzeln aus Fichtenholz, zugesetzt. Grundsätzlich kann die Dosierung des Salzes der dithionigen Säure jederzeit während des Kochprozesses oder auch davor geschehen. Bevorzugt sind allerdings die folgenden Dosierungsvarianten: The salt of dithionous acid, preferably sodium dithionite (Na2S20 4) Calciumdithionit (CaS20 4), zinc dithionite (ZnS20 4), particularly preferably sodium dithionite, in the mixture of lignocellulosic material, preferably of wood chips from spruce wood, and the cooking acid, as described above in an amount in the range from 0.1 to 4.0% by weight, preferably from 1.0 to 2.0% by weight, based in each case on the oven-dried lignocellulose-containing material, preferably the oven-dried wood chips from spruce wood. Basically, the dosage of the salt of the dithionic acid at any time during the cooking process or before it happen. However, the following dosage variants are preferred:
a) am Anfang der 2. Phase a) at the beginning of the second phase
b) am Anfang der 4. Phase  b) at the beginning of the 4th phase
c) in ca. der Hälfte der 4. Phase Bevorzugt wird das Salz der dithionigen Säure am Anfang der 2. Phase, also der Imprägnierphase, dosiert.  c) in about half of the 4th phase Preferably, the salt of the dithionic acid at the beginning of the second phase, ie the impregnation, dosed.
Ein für das erfindungsgemäße Verfahren gut geeigneter Sulfataufschluss wird im Folgenden beschrieben. A sulphate digestion which is well suited for the process according to the invention is described below.
Als lignocellulosehaltiges Material werden Hölzer, wie Laub- oder vorzugsweise Nadelhölzer, besonders bevorzugt Fichtenhölzer, bevorzugt als Hackschnitzel, eingesetzt. As lignocellulosic material are woods, such as deciduous or preferably coniferous wood, particularly preferably spruce wood, preferably used as wood chips.
Grundsätzlich kann als Kochlauge das für das Sulfatverfahren bekannte Gemisch aus Natron- lauge (wässrige NaOH), Natriumsulfid (Na2S) und Natriumsulfat (im folgenden auch„Na2S04") und gegebenenfalls Natriumcarbonat (im folgenden auch„Na2C03") verwendet werden, dem das Salz der dithionigen Säure, vorzugsweise ausgewählt aus der Gruppe bestehend aus Nat- riumdithionit, Zinkdithionit, Calciumdithionit, in einer Menge im Bereich von 0,1 bis 4 Gew.-% bezogen auf die Menge an ofentrockenem lignocellulosehaltigen Material zugegeben wurde. In principle, the mixture known for the sulphate process from sodium hydroxide solution (aqueous NaOH), sodium sulphate (Na 2 S) and sodium sulphate (hereinafter also "Na 2 SO 4") and optionally sodium carbonate (hereinafter also "Na 2 CO 3"), which contains the salt the dithionic acid, preferably selected from the group consisting of sodium dithionite, zinc dithionite, calcium dithionite, in an amount in the range of 0.1 to 4 wt .-% based on the amount of oven-dry lignocellulose-containing material was added.
Eine gut geeignete Kochlauge für das erfindungsgemäße Sulfatverfahren ist im Folgenden beschrieben: A suitable cooking liquor for the sulphate process according to the invention is described below:
Die Kochlauge für den Sulfataufschluss enthält üblicherweise als wirksame Kochchemikalien NaOH und Natriumsulfid (Na2S). Die Summe beider Substanzen (ausgedrückt als NaOH) relativ zum lignocellulosehaltigen Material, vorzugsweise Holz (ofentrocken (otro) gerechnet), ist das Alkaliverhältnis. Dieses Verhältnis liegt üblicherweise im Bereich von 20 bis The cooking liquor for sulphate pulping usually contains NaOH and sodium sulphide (Na2S) as effective cooking chemicals. The sum of both substances (expressed as NaOH) relative to the lignocellulose-containing material, preferably wood (oven-dry (otro)), is the alkali ratio. This ratio is usually in the range of 20 to
24 Gew.-%. Die notwendige Konzentration dieser Substanzen in der Kochlauge ist üblicherweise abhängig vom sogenannten„Laugenverhältnis". Hierunter versteht der Fachmann Massenanteile Kochlauge in Relation zu Massenanteilen lignocellulosehaltigem Material, vorzugsweise Holz (ofentrocken (otro) gerechnet). Bei Nadelhölzern, beispielsweise Fichte und Kiefer liegt dieses Laugenverhältnis üblicherweise in Abhängigkeit von der Fülldichte an Holz im Kocher im allgemei- nen im Bereich von 4 :1 bis 4,5 : 1 , beispielsweise 4,2 : 1. Somit liegt die Konzentration an wirksamem Alkali in der Kochlauge beispielsweise im Bereich von 45 bis 60 g/l. Der Anteil an Natriumsulfid (Na2S) am wirksamen Gesamtalkali ist die Sulfidität (in % angegeben). Diese liegt in der Regel im Bereich von 30 bis 38 %, beispielsweise 30 %. 24% by weight. The necessary concentration of these substances in the cooking liquor is usually dependent on the so-called "liquor ratio." In the case of softwoods, for example spruce and pine, this liquor ratio is understood as meaning mass fractions of cooking liquor in relation to mass fractions of lignocellulose-containing material, preferably wood (oven-dry (otro)) usually depending on the filling density of wood in the digester, generally in the range from 4: 1 to 4.5: 1, for example 4.2: 1. Thus, for example, the concentration of active alkali in the cooking liquor is in the range from 45 to 60 g / l. The content of sodium sulfide (Na2S) in the total effective alkali is the sulfidity (expressed in%). This is usually in the range of 30 to 38%, for example 30%.
Die Kochlauge für das erfindungsgemäße Sulfatverfahren enthält ein Salz der dithionigen Säu- re, vorzugsweise ausgewählt aus der Gruppe bestehend aus Natriumdithionit, Zinkdithionit, Calciumdithionit, in einer Menge im Bereich von 0,1 bis 4 Gew.-% bezogen auf die Menge an ofentrockenem lignocellulosehaltigen Material. The cooking liquor for the sulphate process according to the invention contains a salt of the dithionic acid, preferably selected from the group consisting of sodium dithionite, zinc dithionite, calcium dithionite, in an amount in the range from 0.1 to 4% by weight, based on the amount of oven-dried lignocellulose-containing Material.
Der pH-Wert der Kochlauge für das erfindungsgemäße Sulfatverfahren liegt am Anfang des Kochprozesses üblicherweise bei etwa 14. The pH of the cooking liquor for the sulphate process according to the invention is usually about 14 at the beginning of the cooking process.
Die Kochung des lignocellulosehaltigen Materials mit der Kochlauge für das erfindungsgemäße Sulfatverfahren findet in den üblichen Kochern diskontinuierlich oder kontinuierlich statt. Die Gesamtkochzeit für das erfindungsgemäße Sulfatverfahren liegt üblicherweise im Bereich von 200 bis 400 Minuten, vorzugsweise 240 bis 300 Minuten. The cooking of the lignocellulosic material with the cooking liquor for the sulfate process according to the invention takes place in the usual digesters discontinuous or continuous. The total cooking time for the sulfate process of the invention is usually in the range of 200 to 400 minutes, preferably 240 to 300 minutes.
Die Kochtemperatur für das erfindungsgemäße Sulfatverfahren liegt im Bereich von 160 bis 185 °C, beispielsweise bei 170 °C. The boiling temperature for the sulfate process of the invention is in the range of 160 to 185 ° C, for example at 170 ° C.
Das Salz der dithionigen Säure, vorzugsweise ausgewählt aus der Gruppe bestehend aus Natriumdithionit, Zinkdithionit, Calciumdithionit, besonders bevorzugt Natriumdithionit, wird im erfindungsgemäßen Sulfatverfahren der Mischung des lignocellulosehaltigen Materials und der Kochlauge in einer Menge im Bereich von 0,1 bis 4,0 Gew.- %,, vorzugsweise 1 ,0 bis 2,0 Gew.- %, jeweils bezogen auf das ofentrockene lignocellulosehaltige Material, zugesetzt. The salt of the dithionic acid, preferably selected from the group consisting of sodium dithionite, zinc dithionite, calcium dithionite, more preferably sodium dithionite, is used in the sulphate process of the invention for mixing the lignocellulosic material and the cooking liquor in an amount ranging from 0.1 to 4.0 wt. %, preferably 1.0 to 2.0% by weight, based in each case on the oven-dried lignocellulose-containing material.
Grundsätzlich kann die Dosierung des Salzes der dithionigen Säure jederzeit während des Kochprozesses des erfindungsgemäßen Sulfatverfahrens geschehen. Bevorzugt wird das Salz der dithionigen Säure in der Imprägnierphase, der Endphase des Aufschlusses oder in der Hauptphase des Aufschlusses des erfindungsgemäßen Sulfatverfahrens zugegeben besonders bevorzugt in der der Endphase des Aufschlusses oder in der Hauptphase des Aufschlusses des erfindungsgemäßen Sulfatverfahrens. Das erfindungsgemäße Verfahren zur herstellung aus Zellulose aus lignocellulosehaltigem Material mittels Sulfitaufschluß oder Sulfataufschluß liefert Zellstoff in guter Ausbeute bei guter Delignifizierung des lignocellulosehaltigen Materials. Der Weißgrad des ungebleichten Zellstoffs ist verbessert. Der Zusatz eines Salzes der dithionigen Säure im erfindungsgemäßen Sulfatverfahren verringert die Konzentration übelriechender Substanzen vorzugsweise Mercaptanen im Abgas des Sulfatkochprozesses. Beispiele In principle, the dosage of the salt of the dithionic acid can be done at any time during the cooking process of the sulphate process according to the invention. The salt of the dithionic acid is preferably added in the impregnation phase, the final phase of the digestion or in the main phase of the digestion of the sulphate process according to the invention, particularly preferably in the final phase of the digestion or in the main phase of the digestion of the sulphate process according to the invention. The process according to the invention for the production of cellulose from lignocellulose-containing material by means of sulfite pulping or sulfate pulping produces pulp in good yield with good delignification of the lignocellulose-containing material. The whiteness of the unbleached pulp is improved. The addition of a salt of the dithionic acid in the sulfate process of the invention reduces the concentration of malodorous substances, preferably mercaptans in the exhaust gas of the sulfate cooking process. Examples
(I) Sulfitaufschluß nach dem Bisulfitverfahren mit Mg(HS03)2 als Komponente der Kochsäure A) Lignocellulosehaltiges Material: (I) Sulfite digestion by the bisulfite method with Mg (HSO) 2 as a component of the cooking acid A) Lignocellulose-containing material:
Fichtenholzhackschnitzel vorsortiert und 2 bis 3 Tage vor der Kochung an der Raumluft vorgetrocknet, Wassergehalt im Bereich von 23,4 bis 33,2 Gew.-%, im Mittel etwa 30 Gew.-%  Spruce wood chips pre-sorted and pre-dried in the room air for 2 to 3 days before cooking, water content in the range of 23.4 to 33.2 wt .-%, on average about 30 wt .-%
B) Kochsäure: B) Cooking acid:
Rechnerisch 2,7 Gew.-% MgO pro Liter. pH-Wert vor der Kochung (Anfangs-pH-Wert) 3,8.Calculated 2.7 wt .-% MgO per liter. pH before boil (initial pH) 3.8.
1 100 g MgCÜ3 wurden in 17 Liter entionisiertem Wasser aufgeschlämmt, um eine rechnerische MgO-Konzentration von ca. 2,7 Gew.-% zu erhalten. In die Suspension wurde gasförmiges Schwefeldioxid (SO2) eingeleitet bis der pH-Wert 3,8 betrug. C) Kochung 1 100 g of MgCl 3 were slurried in 17 liters of deionized water to give a calculated MgO concentration of about 2.7% by weight. Gaseous sulfur dioxide (SO 2) was introduced into the suspension until the pH was 3.8. C) cooking
3200 g (ofentrocken (otro) gerechnet) Fichtehackschnitzel mit einem ursprünglichen Wassergehalt wie in A) beschrieben und 16 Liter der Kochsäure aus B) wurden in den diskontinuierlichen Kocher mit einem Fassungsvermögen von 25 Liter gefüllt, entsprechend einem Mengen- verhälnis Kochsäure : otro Holz von 5 : 1 . Der Kocher verfügte über eine Säureumwälzung und elektrische Mantelheizung sowie einen Temperaturregler, Manometer, Temperatursensor und pH-Elektrode, sowie angeschlossenes EDV-System.  3200 g (oven-dry (otro) calculated) spruce chips with an original water content as described in A) and 16 liters of the cooking acid from B) were filled in the discontinuous cooker with a capacity of 25 liters, according to a quantitative ratio of cooking acid: otro wood of 5: 1. The cooker had an acid circulation and electric jacket heating as well as a temperature controller, manometer, temperature sensor and pH electrode, as well as connected EDP system.
Es wurde folgendes Heizprogramm durchgeführt: 1 . Phase: 105 min Anheizzeit von Raumtemperatur (23 °C) auf 105 °C The following heating program was carried out: 1. Phase: 105 min heating time from room temperature (23 ° C) to 105 ° C
2. Phase: 90 min Haltezeit (Imprägnierphase) bei 105 °C  2nd phase: 90 min holding time (impregnation phase) at 105 ° C
3. Phase: 60 min Hochheizzeit von 105 °C auf Fertigkochtemperatur 155 °C  3rd phase: 60 min heating-up time from 105 ° C to final cooking temperature 155 ° C
4. Phase: 195 min Fertigkochzeit bei Fertigkochtemperatur 155 °C  4th phase: 195 min. Final cooking time at final cooking temperature 155 ° C
5. Phase: ca. 60 min Abgaszeit (nach Erreichen der Kochdauer Heizung aus) bis Tempe- ratur unter 100 °C fiel.  5th phase: approx. 60 min. Exhaust gas time (heating off after reaching the cooking time) to temperature below 100 ° C.
Die Gesamtaufschlußzeit betrug 510 min (8 h 30 min). Der Druck im Kocher betrug am Ende der Fertigkochzeit 8 bis 9 bar. The total digestion time was 510 min (8 h 30 min). The pressure in the digester was 8 to 9 bar at the end of the final cooking time.
Natriumdithionit (Blankit®S der BASF SE) wurde in Wasser gelöst per Dosierpumpe binnen 10 min in den Kocher zum Gemisch zugegeben und zwar 32 g reines Na2S204 (1 Gew.-% Na2S204 bezogen auf eingesetztes otro gerechnetes Holz) bzw. 64 g reinens Na2S204 (2 Gew.-% Na2S204 bezogen auf eingesetztes otro gerechnetes Holz). Die Zugabezeitpunkte des Natriumdithionits waren, pro Versuch, wie folgt: Sodium dithionite (Blankit®S from BASF SE) was dissolved in water by metering pump within 10 min in the digester added to the mixture and that 32 g of pure Na2S20 4 (1 wt .-% Na2S20 4 based on otro counted wood used) or 64 g pure Na2S20 4 (2 wt .-% Na2S20 4 based on used otro counted wood). Sodium dithionite addition times were, per experiment, as follows:
Am Anfang der Haltezeit (Imprägnierphase), ca. 105 min nach Versuchsbeginn oder am Anfang der Fertigkochzeit , ca. 255 min nach Versuchsbeginn oder in der Hälfte der Fertigkochzeit, ca. 360 min nach Versuchsbeginn. At the beginning of the holding time (impregnation phase), approx. 105 minutes after the start of the experiment or at the beginning of the final cooking time, approx. 255 minutes after the start of the test or in the half of the finished cooking time, approx. 360 minutes after the start of the test.
Bei Versuch W 16 wurden die Hackschnitzel unmittelbar vor dem Aufschluß mit einer solchen Menge wässriger Lösung von Natriumdithionit (Blankit®S der BASF SE) imprägniert, entsprechend 1 Gew.-% reinens Na2S204 bezogen auf eingesetztes otro gerechnetes Holz. Nach Beendigung der Aufschlüsse wurde der Zellstoff entnommen, mit Wasser versetzt und mit einem Rührgerät zerfasert. Der zerfaserte Zellstoff wurde in ein Sieb gefüllt, mit Wasser gewaschen und in einer Zentrifuge entwässert. In experiment W 16, the chips were impregnated immediately before digestion with such an amount of aqueous solution of sodium dithionite (Blankit®S BASF SE), corresponding to 1 wt .-% pure Na 2 S 20 4 based on otro computed timber used. After completion of the digestions, the pulp was removed, mixed with water and defibered with a stirrer. The shredded pulp was filled into a sieve, washed with water and dehydrated in a centrifuge.
D) Aufstellung und Auswertung D) Setup and evaluation
Tabelle 1 gibt die Versuche wieder: Table 1 shows the experiments:
Tabelle 1 : Table 1 :
[1] Die Werte bedeuten Anzahl Minuten nach Versuchsbeginn, ergo Start der ersten Aufheizung [2] Natriumdithionit Na2S204 In Tabelle 2 sind die Ergebnisse der Versuche aus Tabelle 1 zusammengestellt: [1] The values mean number of minutes after the start of the experiment, ergo start of the first heating [2] sodium dithionite Na 2 S 2 0 4 Table 2 summarizes the results of the experiments in Table 1:
Tabelle 2: Table 2:
Darin bedeuten: In this mean:
Gutstoff ausbeute bedeutet erhaltene Zellstoffmenge (ohne Grobstoff bzw. Splitteranteil) in Relation zum eingesetzten Holz; sie wurde bestimmt durch Wägung und Trockengehaltsmessung. Acceptance of raw material means amount of pulp received (without coarse or splinter content) in relation to the wood used; It was determined by weighing and dry content measurement.
Die Kappazahl gibt die Härte des Zellstoffs an und wurde bestimmt gemäß ISO 302. Vereinfacht gesagt, wird bei der Bestimmung der Kappa-Zahl in einer wäßrigen Zellstoffsuspension im sauren Medium unter definierten Bedingungen der Kaliumpermanganatverbrauch (KMnCM- Verbrauch) gemessen. Je höher der Ligningehalt im Zellstoff ist, desto höher ist der Kalium- permanganatverbrauch und somit die Kappa-Zahl.Je Höher die Kappazahl um so höher der Restligningehalt des Zellstoffs, um so härter ist in der Regel der Zellstoff. The kappa number indicates the hardness of the pulp and was determined in accordance with ISO 302. Put simply, when determining the kappa number in an aqueous pulp suspension in an acidic medium under defined conditions, the potassium permanganate consumption (KMnCM consumption) is measured. The higher the lignin content in the pulp, the higher the consumption of potassium permanganate and thus the kappa number. The higher the kappa number, the higher the residual lignin content of the pulp, the harder is the pulp in general.
Weißgrad (R457) bedeutet Remission bei 457 nm und wurde bestimmt am Gerät Datacolor El- repho® nach ISO 2470. Whiteness (R457) means remission at 457 nm and was determined on the Datacolor Elrepho® instrument according to ISO 2470.
Die Viskositätsbestimmung wurde nach ISO 5351/1 durchgeführt (International Standard ISO 5351/1 , Cellulose in dilute Solutions - Determination of liminting viscosity number, Part 1 : Me- thod in cupri-ethylene-diamine (CED) Solution, First edition 1981 -12-01 ). Dabei wird eine Lösung der Cellulose in Kupferethylendiamin-Lösung hergestellt. Die Konzentration des Lösungsmittels ist festgelegt. Die Konzentration an Cellulose in der Lösung ist entsprechend der Probe bei der Bestimmung festzulegen. Gemessen wird die Durchlaufzeit, sowohl des Lösungsmittels als auch der Cellulose-Lösung durch ein Kapillar-Viskosimeter bei 25 °C. Die Berechnung der Grenzviskositätszahl erfolgt aus den Ergebnissen bei der Bestimmung und der bekannten Konzentration der Cellulose-Lösung nach der Martin- Gleichung. Die Messung wurde nach der Alternative A der Bestimmungsmethode durch geführt (International Standard ISO 5351/1 , Cellulose in dilute Solutions - Determination of liminting viscosity number, Part 1 : Method in cupri-ethylene-diamine (CED) Solution, First edition 1981 -12-01 ). Dabei wird bei niedriger Cellulosekonzentration gearbeitet und für die Messung der Durchlaufzeiten von Lösungsmittel und Celluloselösung die gleiche Kapillare verwendet. The viscosity determination was carried out according to ISO 5351/1 (International Standard ISO 5351/1, Cellulose in dilute Solutions - Determination of liming viscosity number, Part 1: Method in cupri-ethylene-diamine (CED) Solution, First edition 1981 -12 -01). In this case, a solution of cellulose in copper ethylenediamine solution is prepared. The concentration of the solvent is fixed. The concentration of cellulose in the solution should be determined according to the sample used in the determination. The throughput time of both the solvent and the cellulose solution is measured by a capillary viscometer at 25 ° C. The calculation of the intrinsic viscosity is based on the results of the determination and the known concentration of the cellulose solution according to the Martin equation. The measurement was carried out according to the alternative A of the determination method (International Standard ISO 5351/1, Cellulose in dilute Solutions - Determination of liming viscosity number, Part 1: Method in cupri-ethylene-diamine (CED) Solution, First edition 1981 -12 -01). It is carried out at low cellulose concentration and used for the measurement of the transit times of solvent and cellulose solution, the same capillary.
Man erkennt dass die Zugabe des Hilfsmittels, besonders vorteilhaft am Anfang der Imprägnierungsphase, eine verbesserte Kombination der Eigenschaften Gutstoffausbeute/Kappazahl bzw. Weißgrad ergibt. It can be seen that the addition of the auxiliary agent, particularly advantageously at the beginning of the impregnation phase, results in an improved combination of the properties of acceptor yield / kappa number or whiteness.
(II) Sulfataufschluß (II) sulphate digestion
A) Lignocellulosehaltiges Material: A) Lignocellulose-containing material:
Fichten- Kiefern Mischhackschnitzel mit einem Mischungsverhältnis Fi-Ki (7:3) ungetrocknet, Wassergehalt 57 %. Spruce and Pine mixed wood chips with a mixing ratio Fi-Ki (7: 3) undried, water content 57%.
B) Kochlauge: B) cooking liquor:
Die Kochlauge wurde durch Eintragen von handelsüblichen Laborchemikalien in Wasser aus Natronlauge (NaOH) und Natriumsulfid (Na2S) hergestellt. Die Einsatzmenge an Chemikalien wurde so bemessen, dass ein Alkaliverhältnis von 23 % bei einer Sulfidität von 20 % zur Anwendung kam.  The cooking liquor was prepared by adding commercial laboratory chemicals in water from caustic soda (NaOH) and sodium sulfide (Na2S). The amount of chemicals used was calculated so that an alkali ratio of 23% was used at a sulphidity of 20%.
C) Kochung: C) cooking:
Es wurden entsprechend des Holztrockengehaltes soviel Hackschnitzel in einen 101 Kocher eingetragen, dass 1300 g an Trockensubstanz (ofentrocken (otro) gerechnet) Holz verwendet wurden. Der Kocher wurde mit Kochlauge gefüllt. Diese enthielt bei einem gewünschten Alkaliverhältnis von 23 % und einer Sulfidität von 20 % 239,2g NaOH und 59,8g Na2S (als NaOH gerechnet) .Anschließend wurde der Kocherinhalt auf 170°C hochgeheizt und bei dieser Tem- peratur solange gehalten, bis die gewünschte Aufschlussdauer erreicht war. In accordance with the wood dry content, so much wood chips were introduced into a 101 cooker that 1300 g of dry substance (oven-dry (otro)) wood were used. The cooker was filled with cooking liquor. At a desired alkali ratio of 23% and a sulphidity of 20%, this contained 239.2 g of NaOH and 59.8 g of Na 2 S (calculated as NaOH). Subsequently, the contents of the Kocher were heated to 170 ° C. and held at this temperature, until the desired digestion time was reached.
Für die Kalkulation der gewünschten Aufschlussdauer wurde der sog. H-Faktor genutzt. Dabei wird die Temperaturabhängigkeit der relativen Reaktionsgeschwindigkeit für den alkalischen Aufschluss zugrunde gelegt. Für alle Kochungen wurde ein H-Faktor von 3500 realisiert.  For the calculation of the desired digestion time the so-called H-factor was used. The temperature dependence of the relative reaction rate is used for the alkaline digestion. For all cookings an H-factor of 3500 was realized.
Bei ausgewählten Kochungen wurden jeweils 2 Gew.-% relativ zur eingetragenen Holzmenge (ofentrocken (otro) gerechnet) Natriumdithionit zugegeben. Bei einer Kochung erfolgte die Zugabe in der Hauptphase des Aufschlusses, bei einer weiteren Kochung in der Endphase des Aufschlusses. Nach Erreichen des H-Faktors von 3500 wurden die Kochungen durch beenden der Beheizung und Abkühlung in Verbindung mit Druckentspannung („Abgasen") abgebrochen. Der Zellstoff wurde durch kräftiges Rühren zerfasert und gewaschen. D) Aufstellung und Auswertung In selected cooking, in each case 2% by weight, relative to the amount of wood introduced (oven-dry (otro)), sodium dithionite was added. In a cooking, the addition was carried out in the main phase of the digestion, in a further boiling in the final phase of the digestion. After reaching the H-factor of 3500, the cooking was stopped by stopping the heating and cooling in conjunction with pressure release ("flue gases") .The pulp was defibered and washed by vigorous stirring D) Setup and evaluation
Tabelle 3 gibt die Versuche wieder: Table 3 shows the experiments:
Tabelle 3 Table 3
Kochung Nr. Hilfsmittelzugabe [1 ] Zugabezeitpunkt Temperatur bei Zugabe Cooking no. Addition of auxiliary agent [1] Addition time Temperature on addition
1 Ohne  1 without
2 2% Hauptphase 170°C  2 2% main phase 170 ° C
3 2% Endpühase 170°C  3 2% final pH 170 ° C
[1] Natriumdithionit Na2S204 [1] Sodium dithionite Na2S20 4
In der Tabelle 4 ist die Gutstoffausbeute und die Kappa-Zahl dargestellt. Tabelle 4: Kochung Nr. Hilfsmittelzugabe [1 ] Gutstoffausbeute % Kappa-ZahlTable 4 shows the yield of the accepts and the kappa number. Table 4: Cooking No. Auxiliary agent addition [1] Acceptance of raw material% Kappa number
1 ohne 43,3 20,1 1 without 43.3 20.1
2 2 % in Hauptphase 46,4 19,4  2 2% in the main phase 46.4 19.4
3 2 % in Endphase 47,1 19,9  3 2% in final phase 47.1 19.9
[1] Natriumdithionit Na2S2Ü4 [1] Sodium dithionite Na2S2Ü 4
Gutstoffausbeute und Kappa-Zahl sind wie unter (I), oben definiert. Acceptance yield and kappa number are as defined under (I) above.
Man erkennt, dass die Zugabe des Natriumdithionits mit einer deutlichen Ausbeutesteigerung (3 bis 4 Prozentpunkte) verbunden ist, wobei sogar die Kappa-Zahl noch leicht reduziert wurde. E) Reduktion der Methylmercaptan-Emissionen It can be seen that the addition of sodium dithionite is associated with a significant increase in yield (3 to 4 percentage points), with even the kappa number being slightly reduced. E) Reduction of methylmercaptan emissions
Es wurde ein Sulfataufschluß von Nadelholz wie oben beschrieben, durchgeführt A sulphate pulping of softwood was carried out as described above
Während des Ablassens der Gase aus dem Kocher („Abgasen") wurde mit einer Spürpumpe zu unterschiedlichen Zeiten Abgasproben entnommen. Die Konzentration von Methylmercaptan in diesen Proben wurde mit methylmercaptanspezifischen Gasprüfröhrchen gemesen. During the discharge of the gases from the digester ("exhaust gases"), exhaust samples were taken at different times with a tracer pump The concentration of methylmercaptan in these samples was measured with methylmercaptan-specific gas detector tubes.
Die jeweils erste Messung erfolgte unmittelbar nach Beendigung der Kochung, Temperatur im Kocher bei 172 °C. Die folgenden Mesungen erfolgten bei weiter abgesunkenen Kochertemperaturen, siehe Tabelle 5 Die Ergebnisse sind in Tabelle 5 zusammengestellt. Tabelle 5: Methylmercaptankonzentartionen The first measurement was carried out immediately after completion of the cooking, temperature in the digester at 172 ° C. The following measurements were carried out at further reduced temperatures of the digester, see Table 5. The results are summarized in Table 5. Table 5: Methyl mercaptan concentration
[1]: Bezogen auf otro Holz Darin bedeuten:  [1]: Related to otro wood Darin means:
Sulfiditat: Anteil an Na2S im wirksamen Alkali  Sulfidity: Proportion of Na2S in the active alkali
Bei hoher Sulfiditat ist die Methylmercaptankonzentration am größten. Durch den Einsatz von Na2S204 kommt es zu einer Abnahme des Methyl mercatans im Abgas. At high sulfidity, the methylmercaptan concentration is highest. The use of Na2S20 4 leads to a decrease of the methyl mercatane in the exhaust gas.

Claims

Patentansprüche claims
1 . Verfahren zur Herstellung von Zellulose aus lignocellulosehaltigem Material mittels 1 . Process for the production of cellulose from lignocellulosic material by means of
Sulfitaufschluß oder Sulfataufschluß in Gegenwart eines Salzes der dithionigen Säure, dadurch gekennzeichnet, dass das Salz der dithionigen Säure in einer Menge im Bereich von 0,1 bis 4,0 Gew.-% bezogen auf die Menge an ofentrockenem lignocellulosehaltigen Material verwendet.  Sulphite digestion or sulphate digestion in the presence of a salt of the dithionic acid, characterized in that the dithionic acid salt is used in an amount in the range of from 0.1 to 4.0% by weight, based on the amount of oven-dried lignocellulosic material.
2. Verfahren nach Anspruch 1 , wobei das Salz der dithionigen Säure ausgewählt wird aus der Gruppe bestehend aus: Natriumdithionit, Zinkdithionit, Calciumdithionit. 2. The method of claim 1, wherein the dithionic acid salt is selected from the group consisting of: sodium dithionite, zinc dithionite, calcium dithionite.
3. Verfahren nach Anspruch 1 bis 2, wobei das Salz der dithionigen Säure Natriumdithionit ist. 3. The method of claim 1 to 2, wherein the salt of the dithionic acid is sodium dithionite.
4. Verfahren nach Anspruch 1 bis 3, wobei der Sulfitaufschluß im Temperaturbereich von 100 °C bis 160 °C und der Sulfatauschluß im Temperaturbereich von 160 °C bis 185 °C durchgeführt wird. 4. The method of claim 1 to 3, wherein the sulfite pulping in the temperature range of 100 ° C to 160 ° C and the sulfate exclusion in the temperature range of 160 ° C to 185 ° C is performed.
5. Verfahren nach Anspruch 1 bis 4, wobei das lignocellulosehaltige Material Holz ist. 5. The method of claim 1 to 4, wherein the lignocellulosic material is wood.
6. Verfahren nach Anspruch 1 bis 5, wobei das Verfahren diskontinuierlich durchgeführt wird. 6. The method of claim 1 to 5, wherein the process is carried out batchwise.
Verfahren nach Anspruch 1 bis 6, wobei man im Sulfitaufschluß das Salz der dithionigen Säure zugibt, sobald das Gemisch aus Kochsäure und aufzuschließendem lignocellulosehaltigen Material beim Aufheizen eine Temperatur im Bereich von 60 °C bis 1 10 °C erreicht hat und man das so erhaltene Gemisch bei einer Temperatur im Bereich von 100 °C bis 1 10 °C für 30 bis 90 Minuten belässt (Imprägnierungsphase). A process as claimed in any of claims 1 to 6, wherein the salt of the dithionic acid is added in the sulfite digestion as soon as the mixture of cooking acid and lignocellulose-containing material has reached a temperature in the range from 60 ° C to 110 ° C during heating and the mixture obtained in this way at a temperature in the range of 100 ° C to 1 10 ° C for 30 to 90 minutes leaves (impregnation phase).
Verfahren nach Anspruch 1 bis 6, wobei man im Sulfataufschluß das Salz der dithionigen Säure in der Imprägnierphase, der Hauptphase oder der Endphase des Aufschlusses zugibt. Process according to Claims 1 to 6, in which the salt of the dithionic acid in the impregnation phase, the main phase or the final phase of the digestion is added in the sulfate digestion.
Verwendung von Salzen der dithionigen Säure zur Verminderung der Konzentration übel riechender Substanzen in einem Verfahren zur Herstellung von Zellulose aus lignocellulosehaltigem Material mittels Sulfitaufschluß oder Sulfataufschluß. Use of salts of dithionic acid to reduce the concentration evil smelling substances in a process for the production of cellulose from lignocellulosic material by means of sulphite digestion or sulphate digestion.
EP13805310.3A 2012-12-12 2013-12-02 Use of sodium dithionite in a cellulose pulping process Active EP2931968B1 (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2021058483A1 (en) * 2019-09-23 2021-04-01 Université Catholique de Louvain Process for producing lignin components from lignocellulosic biomass

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* Cited by examiner, † Cited by third party
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CN112900130B (en) * 2021-02-02 2022-08-12 大连工业大学 Method for reducing whiteness reduction of cooked plant fibers

Family Cites Families (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE912169C (en) * 1952-02-22 1954-05-24 Georg Jayme Dr Ing Process for the alkaline digestion of plant substances
FR1150451A (en) * 1956-05-04 1958-01-14 Saint Gobain Improvement in the manufacturing processes of semi-chemical cellulose pulps
FR2615874B1 (en) * 1987-05-25 1992-02-21 Atochem PROCESS FOR THE PREPARATION OF CHEMICOTHERMOMECHANICAL PASTES
JP5207191B2 (en) * 2006-05-19 2013-06-12 ザ リサーチ ファンデーション オブ ステート ユニヴァーシティ オブ ニューヨーク Method for carbonate pretreatment and pulping of cellulosic materials
US20080105392A1 (en) * 2006-11-03 2008-05-08 Duggirala Prasad Y Method and composition for improving fiber quality and process efficiency in mechanical pulping
US20090090478A1 (en) * 2007-10-05 2009-04-09 Hollomon Martha G Selectivity improvement in oxygen delignification and bleaching of lignocellulose pulp using singlet oxygen
US20120168102A1 (en) * 2009-04-02 2012-07-05 Sung-Hoon Yoon Pulping process for quality protection including methods for hemicellulose extraction and treatment of hemicellulose-extracted lignocellulosic materials

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2014090609A1 *

Cited By (1)

* Cited by examiner, † Cited by third party
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WO2021058483A1 (en) * 2019-09-23 2021-04-01 Université Catholique de Louvain Process for producing lignin components from lignocellulosic biomass

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