[go: up one dir, main page]

WO2000077294A1 - Digesting liquor for pulp and method for producing pulp - Google Patents

Digesting liquor for pulp and method for producing pulp Download PDF

Info

Publication number
WO2000077294A1
WO2000077294A1 PCT/JP2000/003834 JP0003834W WO0077294A1 WO 2000077294 A1 WO2000077294 A1 WO 2000077294A1 JP 0003834 W JP0003834 W JP 0003834W WO 0077294 A1 WO0077294 A1 WO 0077294A1
Authority
WO
WIPO (PCT)
Prior art keywords
pulp
cooking liquor
cooking
liquor
polysulfide
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.)
Ceased
Application number
PCT/JP2000/003834
Other languages
French (fr)
Japanese (ja)
Inventor
Tatsuya Andoh
Junji Tanaka
Toshihiko Sumino
Keigo Watanabe
Makoto Nakao
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kawasaki Kasei Chemicals Ltd
Nippon Paper Industries Co Ltd
Jujo Paper Co Ltd
AGC Inc
Original Assignee
Kawasaki Kasei Chemicals Ltd
Asahi Glass Co Ltd
Nippon Paper Industries Co Ltd
Jujo Paper Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Kawasaki Kasei Chemicals Ltd, Asahi Glass Co Ltd, Nippon Paper Industries Co Ltd, Jujo Paper Co Ltd filed Critical Kawasaki Kasei Chemicals Ltd
Priority to JP2001503731A priority Critical patent/JP4704638B2/en
Priority to AU51097/00A priority patent/AU5109700A/en
Publication of WO2000077294A1 publication Critical patent/WO2000077294A1/en
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

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
    • 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
    • D21C3/22—Other features of pulping processes

Definitions

  • the present invention relates to an effective pulp cooking liquor for cooking lignocellulosic materials and a method for producing pulp and pulp, and more particularly to a novel and useful pulp capable of improving pulp yield with a small amount of chemical solution
  • the present invention relates to a cooking liquor and a pulp manufacturing method using the pulp cooking liquor.
  • the main method for producing chemical pulp that has been industrially implemented so far is the alkaline cooking method of lignocellulosic materials for wood chips, of which alkaline cooking liquor is mainly composed of sodium hydroxide and sodium sulfide.
  • the craft method using is often used.
  • the quinone cooking method in which a quinone compound is present in such a kraft cooking method, is also widely known. According to the quinone cooking method, it is also known that, when compared with the same kappa monovalent value of pulp, the yield of pulp increases and the amount of cooking liquor used (chemical solution) decreases.
  • the quinone compound oxidizes and stabilizes the terminal aldehyde group of cellulose and hemicellulose in the wood chip, thereby suppressing the cell opening and the peeling reaction which is the hemicellulose dissolution reaction.
  • the quinone compound which has been reduced to a hydroquinone form by itself acts on lignin, reduces and elutes the lignin, and is itself oxidized to the quinone form.
  • the quinone compound stabilizes cellulose and hemicellulose through its own redox cycle and promotes delignification, thereby improving pulp yield when compared with the same kappa monovalent value of pulp. At the same time, it has the effect of reducing the amount of active alkali required for cooking.
  • polysulfide (polysulfide) digestion is widely known as a technique for improving pulp yield.
  • the polysulfide cooking method is a cooking method using a cooking liquor obtained by oxidizing white liquor used for kraft pulp cooking and partially converting sulfide ions in components into polysulfide ions. According to such a polysulfide digestion method, the terminal alcohol of cellulose and hemicellulose is used.
  • PS polysulfide
  • this cooking method produces the above-mentioned effects synergistically.
  • the PS-quinone cooking method improves the pulp yield at the same monovalent kappa and reduces the amount of active alkali used. Due to both effects, if the same amount of unbleached pulp is obtained, the amount of chemical solution used is small, so the load on the recovery boiler is reduced, and the power blister value is reduced, so that the load on the subsequent bleaching process is reduced. Has the effect.
  • pulp cooking liquor that can further improve the pulp yield and reduce the amount of chemical solution used without disrupting the chemical solution recovery balance in the pulp mill is desired. It is also desired to reduce the load on the recovery boiler.
  • pulp cooking liquor improvement such as pulp yield, differs depending on the type of wood chip used.
  • a chip selected from the scientific name: Fagus Crenata Blue as wood chip is selected and compared with the case of cooking with ordinary kraft pulp (KP).
  • KP ordinary kraft pulp
  • the pulp yield is increased by about 1% with respect to the absolutely dried chips compared with the same kappa monovalent pulp obtained, and the amount of cooking liquor (chemical solution) used There decreased about 1% relative to the bone-dry chip, as active alkali (N a 2 0 equivalent).
  • the pulp yield increases by about 16 with respect to the absolutely dry chips compared with the same kappa monovalent pulp obtained, but the cooking liquor used (chemical solution used) ) amount increases about 1% relative to the bone-dry chip, as active alkali (N a 2 0 equivalent).
  • the effects of each are said to appear synergistically.
  • the present invention provides a novel and useful pulp cooking liquor capable of improving the pulp yield with a small amount of added chemical solution and reducing the load on the recovery boiler, and a pulp manufacturing method using this pulp cooking liquor.
  • the purpose is to provide. Disclosure of the invention
  • the present invention relates to a digestion method for producing pulp having a kappa monovalent value of 10 to 45, in which the liquid ratio to absolutely dry chips is 1.5 to 5.0 LZ kg, and the maximum temperature is 140 to 180.
  • the wood chips scientific name: chips selected from Fagus C renata Blume
  • pulp of 8 When pulp of 8 is obtained, increase pulp yield by 3.5% or more and add Providing pulp cooking liquor, characterized in that the cooking liquor to reduce the rate more than 2%.
  • This invention is hereinafter referred to as a first invention.
  • the present invention relates to a white liquor or a green liquor containing at least polysulfide ions, wherein the concentration of sulfur sulfide constituting polysulfide ions is 6 gZL or more, and 0.01 to 1.
  • This invention is hereinafter referred to as a second invention.
  • the pulp cooking liquor of the present invention when pulp obtained by cooking is compared with the same kappa monovalent value, the effect of improving the yield and the effect of reducing the amount of active alkali used are achieved. Therefore recovery The load on the boiler can be reduced, and the cooking time can be reduced.
  • the present invention is applicable to all current pulp digestion systems.
  • the liquid ratio to the absolutely dry chip is 1.5 to 5.OLZkg
  • the maximum temperature is 140 to It is a pulp cooking liquor applicable to cooking methods in which the temperature is 180 ° C and the time required for the chips to reach the maximum temperature is 5 minutes or more. It is defined as a pulp cooking liquor having a predetermined effect when compared under certain cooking conditions.
  • the lignocellulosic material scientific name: F agus C renata B l um tip selected from e, N a OH: 70 g / L, N a 2 S: 3 0 g / L, N a 2 C 0 3: 1 5 g / L (N a 2 0 equivalent) as needed to evaporation solution liquid composition of distilled water was added, liquor ratio: 3. cooked under given conditions at 0 L / kg (bone dry per chip) Then, the temperature of the heating pulp file is such that the kappa monovalent value of the pulp becomes 18; for example, the temperature is raised from room temperature to 160 ° C in 60 minutes, and the temperature is raised to 160 ° C for 41 minutes.
  • Pulping is performed under conditions that are maintained.
  • a standard chip is a wood chip capable of obtaining pulp such that the pulp yield at that time is 50 to 51% based on the absolutely dry chip.And, using the same standard chip of the same material and the same shape, If necessary, add distilled water to make the same liquor ratio, raise the temperature with the same heating profile, and cook under the same conditions for the infiltration of the cooking liquor, for example, the same chip shape and size. Try to get 18 pulp.
  • cooking is performed by adjusting the amount of cooking liquor added. Increase the yield of the resulting pulp with a zipper value of 18 to 3.5% or more with respect to the absolutely dry chips and reduce the active alkali addition rate per absolutely dry chip by 2% or more with respect to the chip weight. Pulp cooking liquor.
  • the cooking liquor according to the present invention when a chip selected from the scientific name: Fagus C renata B 1 ume is selected as a wood chip, compared with a case where ordinary craft pulp (KP) cooking is performed, For the first time, an unprecedented large effect of improving pulp yield by 3.5% or more and a large effect of reducing chemical consumption by 2% or more as an active alkali addition rate are achieved.
  • the digester used for defining the pulp digestion liquid as described above is preferably a rotatable digester rather than a stationary cooker.
  • the pulp cooking liquor of the present invention preferably contains sodium hydroxide and sodium sulfide, and contains polysulfide ions.
  • polysulfide ion what is polysulfide ion?
  • Sulfur polysulfide refers to sulfur with an oxidation number of 0 in polysulfide ions and (X-1) sulfur in S. Further, N a
  • the 2 S state sulfur shall be the generic term for sulfide ions and sulfur (Sx 2 in one minute sulfur) of Ta ⁇ hydride ion during the oxidation number II.
  • the active alkali (hereinafter also referred to as "AA") is obtained by converting the N a OH + N a 2 S in N a 2 0 concentration.
  • the pulp cooking liquor of the first invention preferably contains polysulfide ion.
  • Examples of the method for producing the pulp cooking liquor containing polysulfide ions include an air oxidation method and an electrolytic method. .
  • the air oxidation method uses a solution containing sodium sulfide such as white liquor in the presence of an activated carbon catalyst. It comes into contact with air and oxidizes sulfide ions to produce polysulfide ions.
  • thiosulfate ion is inevitably produced as a by-product, and it is relatively difficult to increase the concentration of sulfur polysulfide constituting polysulfide ion. For this reason, in the present invention, it may be produced by an air oxidation method, but preferably, an electrolytic method is used.
  • the pulp cooking liquor of the first invention preferably contains a sulfur polysulfide concentration of 6 gZL or more.
  • a sulfur polysulfide concentration of 6 gZL or more.
  • the electrolysis method which is one of the methods for producing a pulp cooking liquor containing polysulfide ions, is particularly preferable as a method for producing a cooking liquor having a sulfur polysulfide concentration of 8 gZL or more.
  • Examples of such an electrolysis method include, for example, PCT No. JP 97/01456, Japanese Patent Application No. 10-16663 74, Japanese Patent Application No. 111-151016, developed by the present inventors. Japanese Patent Application 1 1 1 5 1 0 33 Electrolysis method such as No. 3 can be applied.
  • the electrolysis method when the reaction rate is increased to produce a high sulfur polysulfide concentration as in the air oxidation method, the selectivity is reduced, and a large amount of thiosulfate, which is ineffective for cooking, is not produced.
  • a solution containing sulfide ions for example, a white liquor or the like in an anode chamber of an electrolytic cell having an anode chamber provided with an anode, a cathode chamber provided with a cathode, and a diaphragm separating the two chambers.
  • a cooking liquor containing polysulfide ion can be obtained.
  • the anode must have alkali resistance and oxidation resistance.
  • nonmetals include carbon materials
  • metals include base metals such as nickel, cobalt, and titanium, and alloys and oxides thereof, or platinum, gold, and rhodium. And the like, and alloys and oxides thereof.
  • the structure of the anode is preferably a porous structure having a physically three-dimensional network structure.
  • an alkali-resistant material is preferable, and nickel, Raney nickel, nickel sulfide, steel, stainless steel, or the like can be used.
  • the shape is a flat plate or a mesh shape, and one or a plurality of them are used in a multilayer structure.
  • a three-dimensional electrode combining linear electrodes can also be used.
  • a cation exchange membrane As the membrane separating the anode compartment and the cathode compartment. Force cation exchange membranes guide cations from the anodic compartment to the cathodic compartment, but hinder the transfer of sulfide and polysulfide ions.
  • a cation exchange membrane a polymer membrane in which a cation exchange group such as a sulfonic acid group or a carboxylic acid group is introduced into a hydrocarbon-based or fluorine-based high molecule is preferable. If there is no problem in terms of alkali resistance or the like, a bipolar membrane, an anion exchange membrane, or the like can be used.
  • a part of the sulfide ion of the white liquor or the green liquor is oxidized to generate a polysulfide ion, which is supplied to the digestion step.
  • the pulp cooking liquor of the first invention if it contains polysulfide ions, it is preferable that N a 2 S state sulfur concentration remains 9 g ZL more than N a 2 0 conversion. If the concentration is less than 9 g / L, polysulfide ions become unstable, and the kappa monovalent of the pulp obtained by cooking may increase or the pulp yield may decrease.
  • the cooking liquor of the first invention preferably contains a quinone compound.
  • quinone compounds include 9,10-anthraquinone and 2-methyl-9,10-anthraquino Alkyl, anthraquinones such as 2,4-ethyl-9,10-anthraquinone, 1,4,4a, 9a-tetrahydro9,10-anthraquinone, 1,4-dihidro9,10-anthraquinone Quinone compounds such as, 2- (9,10-anthraquinol) -11-ethanesulfonic acid, 9,10-anthraquinone-2-sulfonic acid, amino-9,10-anthraquinone, and their reduced forms ( A dihydro form or a sodium salt of a dihydro form).
  • the addition to the state in reduced form in quinone body Ru oxidized der It can be either a hydroquinone body.
  • the state after addition may be either.
  • 1,4,4a, 9a-tetrahydro-9,10-anthraquinone is converted to 1,4-dihydro-19,10-dihydroxy-thracenedinatridium salt in an alkaline cooking liquor. ing.
  • the quinone compound preferably contained in the pulp cooking liquor of the first invention is preferably present in the cooking liquor such that the quinone compound is contained in an amount of 0.01 to 1.5% by weight per absolutely dried chip. More preferably rather is 0.02 to 0.06 weight 0/0. If abundance 0.0 less than 1 wt 0/0 per bone dry chips quinone compound is not Kappa monovalent or AA usage digestion after pulp abundance is too small can be reduced, the force wrapper value and AA The relationship between the addition rate and the pulp yield is not improved.
  • the pulp cooking liquor of the second invention is a white liquor or a green liquor containing at least polysulfide ions, wherein the concentration of sulfur sulfide constituting polysulfide ions is 6 gZL or more and 0.0 per absolutely dry chip.
  • 1 1. contains a quinone compound 5 weight 0/0.
  • the method for producing polysulfide ions contained in the cooking liquor may be an air oxidation method as in the case of the cooking liquor of the first invention, but the concentration of sulfur sulfide constituting the polysulfide ions may be reduced.
  • Cooking liquor above 6 g / L is preferably produced electrolytically. The electrolysis method can be performed as described above.
  • the sulfur polysulfide concentration is less than 6 g / L, the effect of improving pulp yield may be reduced. More preferably, it is 8 g / L or more.
  • the quinone compound is present in an amount of 0.01 to 1.5% by weight per absolutely dry chip. More preferably, it is 0.02 to 0.06% by weight. If the amount of the quinone compound is less than 0.01% by weight based on the absolutely dry chips, the amount of the quinone compound is too small to reduce the pulp power and AA consumption of the pulp after digestion. The relationship between additivity and pulp yield is not improved.
  • quinone compound even if the quinone compound is present in an amount exceeding 1.5% by weight, further reduction of pulp power and AA consumption after cooking and improvement of the relationship between pulp yield and pulp yield and AA consumption It is not allowed.
  • Specific examples and forms of the quinone compound are the same as those in the first invention.
  • N a 2 S state sulfur concentration remains N a 2 0 translated at 9 GZL above. If this concentration is less than 9 g / L, the polysulfide ions become unstable, and the pulp obtained by cooking may have a higher strength and the pulp yield may be reduced.
  • the method of adding the quinone compound may be any of a method of adding the compound at one time before or during the cooking or a method of adding the compound in steps.
  • the cooking liquor containing the quinone compound sufficiently penetrates into the chips.
  • the cooking liquor of the present invention is preferably used so that the liquor ratio when performing cooking using a batch digester is 2.0 to 5.0 LZkg per absolutely dry chip. More preferably, it is 2.5 to 4.0 LZkg. If the liquid ratio is less than 2.0 LZkg, the cooking liquor may not sufficiently penetrate into the chips, which may reduce the cooking effect, which is not preferable. When the liquid ratio exceeds 5.OLZkg, the effect of reducing the amount of used chemical liquid decreases, which is not preferable.
  • the liquid ratio is preferably adjusted to 1.5 to 5.0 L Zkg per absolutely dry chip. More preferably, it is 2.0 to 3.5 L / kg. If the liquid ratio is less than 1.5 L / kg, a gas phase is formed in the infiltration stage, and the digestion effect may be reduced, which is not preferable. If the liquid ratio exceeds 5.OL / kg, the effect of reducing the amount of chemical used decreases, which is not preferable. In addition, it is more preferable to use 1.5 to 3.5 L / kg when a softwood chip is used as a lignocellulosic material and 2.5 to 5.0 L / kg when a hardwood chip is used.
  • the cooking effect may be reduced due to insufficient penetration of the alkaline cooking liquor into the chips.
  • the liquor ratio refers to a bone-dry chip weight per liquid volume in the case of batch cooker force 5, in the continuous digester, Ze'inuichi-up flowing into the kettle per unit time It refers to the ratio between the weight and the volume of liquid flowing into the kettle.
  • the composition of white liquor usually used in pulp cooking is that white liquor used in current kraft pulp cooking usually contains 2 to 6 mol 1 ZL as alkali metal ions, of which 90% or more Is sodium ion, and the rest is almost force ion.
  • Anions are mainly composed of hydroxide ions, sulfide ions, and carbonate ions.
  • the sulfide ion concentration is usually 0.5 to 0.8 mo1 / L, and sulfate ions and thiosulfate ions are also included. , Including chloride ion and sulfite ion. It also contains trace components such as calcium, silicon, aluminum, phosphorus, magnesium, copper, manganese and iron.
  • the composition of green liquor is basically the same as white liquor. However, while white liquor is mainly composed of sodium sulfide and sodium hydroxide, green liquor is mainly composed of sodium sulfide and sodium carbonate.
  • a good cooking effect can be obtained with any of the lignocellulosic materials, coniferous or hardwood.
  • conifers such as Crypt 0 meria (cedar), P icea (ezoma, spruce, oshuyu spruce, sika pine), Pinus (radius pine, akamatsu, black pine, etc.), Thuja (bay Japanese cedars and cats), T suga (e.g., pegga), hardwoods such as E uca 1 yptus (eucalyptus), Fagus (beech), Quercus (oak, oak, etc.), and Acacia (acacia) Is raised.
  • Crypt 0 meria cedar
  • P icea ezoma, spruce, oshuyu spruce, sika pine
  • Pinus radius pine, akamatsu, black pine, etc.
  • Thuja bay Japanese cedars and cats
  • T suga
  • test method is as follows.
  • model white liquor was prepared of sodium hydroxide 70 GZL Contact and sodium sulfide 3 0 GZL, sodium carbonate 1 5 g / L (both N a 2 0 equivalent), the active alkali the addition of 1 4, 1 6, 1 8% by weight; was added at a rate of (vs.
  • the cooking liquor is assumed to be a polysulfide solution obtained by oxidizing the model white liquor of the composition of Comparative Example 1 with activated carbon catalyst, and assuming a reaction rate of 60% and a selectivity of 63%.
  • Sodium hydroxide 70 gZL, Na 2 S form 12.0 g / L, sodium carbonate 15 g / L and sodium thiosulfate 3.3 g / (all converted to Na 20 )
  • sulfur polysulfide 5.9 g / (sulfur conversion) model polysulfide cooking liquor was prepared.
  • Nickel plate on anode stack nickel foam on anode (100 mm x 20 mm x 4 mm, average mesh diameter of 0.5 mm, anode surface area per anode chamber volume: 56 0 m 2 Zm 3 , surface area with respect to the diaphragm area: 28 m 2 / m 2 ), a two-chamber electrolytic cell composed of iron expansion metal as a force source and a fluororesin cation exchange membrane as a diaphragm Assembled.
  • the anode chamber is 100 mm high, 20 mm wide and 4 mm thick.
  • the force source chamber is 100 mm high, 20 mm wide and 5 mm thick, and the effective area of the diaphragm is 20 cm.
  • the anode chamber is 100 mm high, 20 mm wide and 4 mm thick.
  • the force source chamber is 100 mm high, 20 mm wide and 5 mm thick, and the effective area of the diaphragm is 20 cm.
  • the digestion was performed under the same temperature conditions as in Comparative Example 1.
  • the kappa monovalent value and pulp yield after cooking are as follows. AA addition rate 0 / o Kappa monovalent pulp yield%
  • the digestion was performed under the same temperature conditions as in Comparative Example 1.
  • the kappa monovalent value and pulp yield after cooking are as follows.
  • Comparative Example 1 is positioned as one of the standard cooking conditions for defining the cooking liquor of the present invention.Comparative Examples and Examples described below were performed in Comparative Examples 1 to 5 and Examples 1 and 2. This is an example in which the same cooking liquor is used under the same cooking conditions as that of a conventional cooking and applied to different types of wood. ⁇ Comparative Example 6>
  • Example 1 The same experiment as in Example 1 was performed using the same wood chips as in Comparative Example 6 and the same cooking liquor as in Example 1.
  • the kappa monovalent value and pulp yield after cooking are as follows.
  • Example 2 The same experiment as in Example 2 was performed using the same wood chips as in Comparative Example 6 and using the same cooking liquor as in Example 2.
  • the kappa monovalent value and pulp yield after cooking are as follows.
  • Example 1 The same experiment as in Example 1 was performed using the same wood chips as in Comparative Example 11 and the same cooking liquor as in Example 1.
  • the kappa monovalent value and pulp yield after cooking are as follows.
  • Example 2 The same experiment as in Example 2 was performed using the same wood chips as in Comparative Example 11 and the same cooking liquor as in Example 2.
  • the kappa monovalent value and pulp yield after cooking are as follows.
  • the pulp yield can be further improved, and the relationship between monovalent kappa and pulp yield can be further improved. That is, according to the present invention, the pulp monovalent value at the same active alkali addition rate is reduced, and the pulp yield is improved at the same motive power value. The effect of reducing the load on the recovery boiler is achieved. Moreover, these effects can be achieved without breaking the chemical solution recovery balance in the pulp mill.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Inorganic Chemistry (AREA)
  • Paper (AREA)

Abstract

A digesting liquor for pulp, characterized in that when a standard chip is digested with the digesting liquor under a temperature profile predetermined for a standard digesting liquor at a liquor ratio of 3.0 L/kg (based on absolutely dried chip) to produce a pulp having a kappa value of 18, the standard chip being a wood chip providing a pulp having a kappa value of 18 in a yield of 50 to 51 % by using a standard digesting liquor having a specific composition under the same conditions and at the same liquor ratio as described above, an increase in yield by 3.5 % or more and a decrease in the ratio of addition of an active alkali to a pulp by 2 % or more are achieved; and a method for producing a pulp using the digesting liquor. The digesting liquor can be used for improving the relationship between a kappa value and a pulp yield, and also for reducing the amount of chemicals to be used and reducing the load on a boiler for recovery.

Description

ノ、°ルプ蒸解液およびノ、。ルプ製造方法 技術分野 No, ° Lup cooking liquor and no. Lup manufacturing method Technical field

本発明は、 リグノセルロース材料を蒸解する効果的なノ、°ルプ蒸解液およびノ、°ルプ製 造方法に関し、 特に、 少ない薬液添加量でパルプ収率を向上させることのできる新規 、 有用なパルプ蒸解液およびこのパルプ蒸解液を用いるパルプ製造方法に関する。 背景技術  The present invention relates to an effective pulp cooking liquor for cooking lignocellulosic materials and a method for producing pulp and pulp, and more particularly to a novel and useful pulp capable of improving pulp yield with a small amount of chemical solution The present invention relates to a cooking liquor and a pulp manufacturing method using the pulp cooking liquor. Background art

これまでに工業的に実施されている化学パルプの主な製造法は、 木材チップのリグ ノセルロース材料のアルカリ性蒸解法であり、 このうち、 水酸化ナトリウムと硫化ナ トリゥムが主成分のアルカリ性蒸解液を用いるクラフト法が多く利用されている。 こ のようなクラフト蒸解法にキノン化合物を存在させて蒸解するキノン蒸解法も広く知 られている。 キノン蒸解法によれば、 パルプの同一カッパ一価で比較した場合、 ノ、レ プ収率が増加するとともに、 用いられる蒸解液 （使用薬液） 量が減少することも知ら れている。  The main method for producing chemical pulp that has been industrially implemented so far is the alkaline cooking method of lignocellulosic materials for wood chips, of which alkaline cooking liquor is mainly composed of sodium hydroxide and sodium sulfide. The craft method using is often used. The quinone cooking method, in which a quinone compound is present in such a kraft cooking method, is also widely known. According to the quinone cooking method, it is also known that, when compared with the same kappa monovalent value of pulp, the yield of pulp increases and the amount of cooking liquor used (chemical solution) decreases.

すなわち、 キノン化合物が木材チップ中のセルロースおよびへミセルロースの末端 アルデヒド基を酸化し安定化させることにより、 セル口一スおよびへミセルロース溶 出反応であるピーリング反応を抑える。 一方、 それ自体は還元されてハイ ドロキノン 型となったキノン化合物はリグニンに作用し、 リグニンを還元溶出させ、 それ自体は 酸化されてキノン型になる。 このように、 キノン化合物はそれ自体の酸化還元サイク ルを通じてセルロースおよびへミセルロースを安定化させ、 脱リグニンを促進させる ことにより、 パルプの同一カッパ一価で比較した場合、 パルプ収率が向上するのと同 時に、 蒸解で必要な活性アルカリ量を減少させるという効果をもたらす。  That is, the quinone compound oxidizes and stabilizes the terminal aldehyde group of cellulose and hemicellulose in the wood chip, thereby suppressing the cell opening and the peeling reaction which is the hemicellulose dissolution reaction. On the other hand, the quinone compound which has been reduced to a hydroquinone form by itself acts on lignin, reduces and elutes the lignin, and is itself oxidized to the quinone form. Thus, the quinone compound stabilizes cellulose and hemicellulose through its own redox cycle and promotes delignification, thereby improving pulp yield when compared with the same kappa monovalent value of pulp. At the same time, it has the effect of reducing the amount of active alkali required for cooking.

一方、 パルプ収率の向上技術として多硫化物 （ポリサルフアイ ド） 蒸解法も広く知 られている。 多硫化物蒸解法とはクラフトパルプ蒸解に用いられる白液を酸化し、 成 分中の硫化物イオンを一部多硫化物イオンに変化させた蒸解液を用いる蒸解法である 。 このような多硫化物蒸解法によれば、 セルロースおよびへミセルロースの末端アル  On the other hand, polysulfide (polysulfide) digestion is widely known as a technique for improving pulp yield. The polysulfide cooking method is a cooking method using a cooking liquor obtained by oxidizing white liquor used for kraft pulp cooking and partially converting sulfide ions in components into polysulfide ions. According to such a polysulfide digestion method, the terminal alcohol of cellulose and hemicellulose is used.

1 デヒド基が多硫化物イオンにより酸化され安定化されることにより、 パルプ収率の向 さらに、 上記の蒸解方法を組み合わせたいわゆる P S (ポリサルファイ ド） キノ ン蒸解法も知られている。 この蒸解方法では上記で述べた効果が相乗的に現れるとい われている。 つまり、 P S—キノン蒸解法の効果として、 同一カッパ一価でのパルプ 収率を向上させ、 使用活性アルカリ量を減少させる。 両効果によ り、 同じ量の未晒し パルプ量を得るならば、 使用薬液量が少なくて済むので回収ボイラーの負荷が減り、 また力ッパー価が小さくなるので後の漂白工程の負荷が減る等の効果がある。 1 A so-called PS (polysulfide) quinone digestion method combining the above digestion methods is also known, in which the aldehyde group is oxidized and stabilized by polysulfide ions to improve the pulp yield. It is said that this cooking method produces the above-mentioned effects synergistically. In other words, the PS-quinone cooking method improves the pulp yield at the same monovalent kappa and reduces the amount of active alkali used. Due to both effects, if the same amount of unbleached pulp is obtained, the amount of chemical solution used is small, so the load on the recovery boiler is reduced, and the power blister value is reduced, so that the load on the subsequent bleaching process is reduced. Has the effect.

しかし、 このようなパルプ蒸解法においては、 パルプ工場内の薬液回収バランスを 崩すことなく、 更にパルプ収率を向上させ、 また薬液使用量の削減を達成できるパル プ蒸解液が望まれ、 また、 回収ボイラーの負荷を低減させることも望まれている。 パルプ蒸解液の改良によるパルプ収率等の効果は、 用いる木材チップによりそ の現れ方に差があるので、 標準となる木材チップを定めて検討するのが好ましい However, in such a pulp cooking method, a pulp cooking liquor that can further improve the pulp yield and reduce the amount of chemical solution used without disrupting the chemical solution recovery balance in the pulp mill is desired. It is also desired to reduce the load on the recovery boiler. The effect of pulp cooking liquor improvement, such as pulp yield, differs depending on the type of wood chip used.

。 そこで、 木材チップとして学名 ： F a g u s C r e n a t a B l umeから 選ばれるチップを選択し、 通常のクラフトパルプ （KP) 蒸解を行った場合と比較し て述べる。 たとえば、 前述したキノン蒸解法の場合、 得られた同一カッパ一価のパル プで比較してパルプ収率が絶乾チップに対して約 1 %増加するとともに、 用いられる 蒸解液 （使用薬液） 量が活性アルカリ （N a20換算） として絶乾チップに対して約 1 %減少する。 . Therefore, a chip selected from the scientific name: Fagus Crenata Blue as wood chip is selected and compared with the case of cooking with ordinary kraft pulp (KP). For example, in the case of the quinone cooking method described above, the pulp yield is increased by about 1% with respect to the absolutely dried chips compared with the same kappa monovalent pulp obtained, and the amount of cooking liquor (chemical solution) used There decreased about 1% relative to the bone-dry chip, as active alkali (N a 2 0 equivalent).

また、 前述した多硫化物蒸解法の場合、 得られた同一カッパ一価のパルプで比 較してパルプ収率が絶乾チップに対して約 1 6増加するが、 用いられる蒸解液 （ 使用薬液） 量も活性アルカリ （N a20換算） として絶乾チップに対して約 1 %増加 してしまう。 更に、 P S (ポリサルファイ ド） 一キノン蒸解法の場合、 それぞれの効 果力'相乗的に現れるといわれている力、 最も大きな効果が得られたとしても、 得られ た同一力ッパ一価のパルプで比較してパルプ収率が絶乾チップに対して最大で 3 %増 加し、 用いられる蒸解液 （使用薬液） 量が活性アルカリ （Na20換算） として絶乾 チップに対して最大 1. 5 %減少するにすぎなかった。 実験室レベルでの蒸解実験 であれば、 パルプ収率の向上と薬液使用量の削減効果が共に大きい蒸解液が調製 可能であるが、 パルプ工場でそのような蒸解液を用いるには、 工場内の薬品バラ ンスを崩さないことが使用の前提となるので、 従来、 パルプ収率が 3. 5 %以上 ±曾カ卩し、 活性アルカリが 2 %以上減少するような蒸解液は得られていない。 In the case of the polysulfide digestion method described above, the pulp yield increases by about 16 with respect to the absolutely dry chips compared with the same kappa monovalent pulp obtained, but the cooking liquor used (chemical solution used) ) amount increases about 1% relative to the bone-dry chip, as active alkali (N a 2 0 equivalent). Furthermore, in the case of PS (polysulfide) monoquinone digestion, the effects of each are said to appear synergistically. Even if the greatest effect is obtained, the same power obtained is the same compared with the pulp the pulp yield and maximum increased by 3% with respect to bone-dry chip, the maximum cooking liquor used (use the drug solution) amount with respect to the bone-dry chip, as active alkali (Na 2 0 equivalent) 1 Only reduced by 5%. Cooking experiments at the laboratory level can prepare cooking liquor that is both effective in improving the pulp yield and reducing the amount of chemical solution used. Chemical rose Since the prerequisite for use is that the pulp should not be destroyed, no cooking liquor has been obtained so far, in which the pulp yield is 3.5% or more and the amount of active alkali is reduced by 2% or more.

そこで、 本発明は、 少ない薬液添加量でパルプ収率を向上させ、 回収ボイラーの負 荷を低減させることができる新規、 有用なノ、°ルプ蒸解液およびこのパルプ蒸解液を用 いるパルプ製造方法を提供することを目的とする。 発明の開示  Accordingly, the present invention provides a novel and useful pulp cooking liquor capable of improving the pulp yield with a small amount of added chemical solution and reducing the load on the recovery boiler, and a pulp manufacturing method using this pulp cooking liquor. The purpose is to provide. Disclosure of the invention

本発明は、 カッパ一価が 1 0〜 4 5のパルプを生産する蒸解法のうち、 絶乾チップ に対する液比が 1. 5〜 5. 0 L Z k gであり、 最高温度が 1 40〜 1 80 °Cであり 、 チップが最高温度に達するまでの時間が 5分以上である蒸解法に適用される蒸解液 であって、 以下の標準蒸解液および液比： 3. 0 L/k g (絶乾チップ当り。 なお、 Lはリッ トルを表す、 本明細書中同じ） で所定の条件下で蒸解したとき、 パルプの力 ッパー価 1 8の時のパルプ収率が 50〜 5 1 %となるパルプが得られる木材チップ （ 学名： F a g u s C r e n a t a B l umeから選ばれるチップ） を標準チップ として、 この標準チップを用い、 同一液比で同一昇温プロファイルにおいて昇温して 、 カッパ一価が 1 8のパルプを得るとき、 パルプ収率を 3. 5%以上上昇させ、 対チ ップ活性アル力リ添加率を 2 %以上低下させる蒸解液であることを特徴とするパルプ 蒸解液を提供する。 この発明を以下第一発明という。  The present invention relates to a digestion method for producing pulp having a kappa monovalent value of 10 to 45, in which the liquid ratio to absolutely dry chips is 1.5 to 5.0 LZ kg, and the maximum temperature is 140 to 180. A cooking liquor applied to a cooking method in which the temperature of the chips is 5 minutes or more until the chips reach the maximum temperature, and the following standard cooking liquor and liquid ratio: 3.0 L / kg (absolutely dry) Pulp with a pulp yield of 50% to 51% when the pulp power is 18 when digested under the specified conditions under L Using the wood chips (scientific name: chips selected from Fagus C renata Blume) obtained as a standard chip, this standard chip is used, and the temperature is raised in the same temperature profile with the same liquid ratio, resulting in 1 kappa monovalent. When pulp of 8 is obtained, increase pulp yield by 3.5% or more and add Providing pulp cooking liquor, characterized in that the cooking liquor to reduce the rate more than 2%. This invention is hereinafter referred to as a first invention.

標準蒸解液組成： N a OH 70 g/L (N a 20換算） Standard cooking liquor composition: N a OH 70 g / L (N a 2 0 equivalent)

N a 2S 30 g/L (N a 20換算） N a 2 S 30 g / L (N a 20 conversion)

Na2C03 1 5 g/L (N a20換算） Na 2 C0 3 15 g / L (N a 20 conversion)

また、 本発明は、 少なくとも多硫化物イオンを含有する白液又は緑液のうち、 多硫 化物イオンを構成する多硫化硫黄濃度が 6 gZL以上で、 絶乾チップ当り 0. 0 1〜 1. 5重量％のキノン化合物を含有することを特徴とする蒸解液を提供する。 この発 明を以下第二発明という。 発明を実施するための最良の形態  In addition, the present invention relates to a white liquor or a green liquor containing at least polysulfide ions, wherein the concentration of sulfur sulfide constituting polysulfide ions is 6 gZL or more, and 0.01 to 1. A cooking liquor characterized in that it contains 5% by weight of a quinone compound. This invention is hereinafter referred to as a second invention. BEST MODE FOR CARRYING OUT THE INVENTION

本発明のノ、°ルプ蒸解液によれば、 蒸解で得られるパルプを同じカッパ一価で比較し たとき、 収率の向上効果と活性アルカリ使用量の低下効果が達成される。 従って回収 ボイラーの負荷を低減でき、 蒸解時間も短縮される。 本発明は現行のすべてのパルプ 蒸解システムに適用することができる。 According to the pulp cooking liquor of the present invention, when pulp obtained by cooking is compared with the same kappa monovalent value, the effect of improving the yield and the effect of reducing the amount of active alkali used are achieved. Therefore recovery The load on the boiler can be reduced, and the cooking time can be reduced. The present invention is applicable to all current pulp digestion systems.

第一発明は、 カッパ一価が 1 0〜4 5のパルプを生産する蒸解法のうち、 絶乾チッ プに対する液比が 1. 5〜 5. O LZk gであり、 最高温度が 1 40〜 1 80 °Cであ り、 チップが最高温度に達するまでの時間が 5分以上である蒸解法に適用されるパル プ蒸解液である。 そして、 ある蒸解条件下で比較した時に所定の効果を有するような パルプ蒸解液として規定される。 すなわち、 リグノセルロース材料として、 学名： F a g u s C r e n a t a B l um eから選ばれるチップを、 N a OH : 70 g/ L、 N a 2S : 3 0 g/L、 N a 2C 03 ： 1 5 g/L (N a 20換算） の組成の蒸 解液に必要に応じて蒸留水を加え、 液比： 3. 0 L/k g (絶乾チップ当り） で 所定の条件下で蒸解し、 得られるパルプのカッパ一価が 1 8になるような昇温プ 口ファイル、 例えば、 室温から 1 6 0 °Cまで 6 0分で昇温して、 1 6 0 °Cで 4 1 分間維持する条件で蒸解を行う。 その時のパルプ収率が絶乾チップに対して 5 0 〜 5 1 %となるようなパルプを得ることができる木材チップを標準チップとする そして、 この同一素材で同一形状の同じ標準チップを用い、 必要に応じて蒸留水を 加えて同一液比とし、 同一昇温プロファイルにて昇温し、 蒸解液の浸透条件、 例えば 、 チップの形状、 大きさ等が同一の条件において蒸解を行い、 カッパ—価 1 8のパル プを得るようにする。 具体的には蒸解液の添加量を加減して蒸解を行う。 その結果得 られた力ッパー価 1 8のパルプの収率を絶乾チップに対して 3. 5 %以上上昇させ、 絶乾チップ当りの活性アルカリ添加率をチップ重量に対して 2 %以上低下させること ができるパルプ蒸解液である。 In the first invention, of the digestion methods for producing pulp having a kappa monovalent value of 10 to 45, the liquid ratio to the absolutely dry chip is 1.5 to 5.OLZkg, and the maximum temperature is 140 to It is a pulp cooking liquor applicable to cooking methods in which the temperature is 180 ° C and the time required for the chips to reach the maximum temperature is 5 minutes or more. It is defined as a pulp cooking liquor having a predetermined effect when compared under certain cooking conditions. That is, as the lignocellulosic material, scientific name: F agus C renata B l um tip selected from e, N a OH: 70 g / L, N a 2 S: 3 0 g / L, N a 2 C 0 3: 1 5 g / L (N a 2 0 equivalent) as needed to evaporation solution liquid composition of distilled water was added, liquor ratio: 3. cooked under given conditions at 0 L / kg (bone dry per chip) Then, the temperature of the heating pulp file is such that the kappa monovalent value of the pulp becomes 18; for example, the temperature is raised from room temperature to 160 ° C in 60 minutes, and the temperature is raised to 160 ° C for 41 minutes. Pulping is performed under conditions that are maintained. A standard chip is a wood chip capable of obtaining pulp such that the pulp yield at that time is 50 to 51% based on the absolutely dry chip.And, using the same standard chip of the same material and the same shape, If necessary, add distilled water to make the same liquor ratio, raise the temperature with the same heating profile, and cook under the same conditions for the infiltration of the cooking liquor, for example, the same chip shape and size. Try to get 18 pulp. Specifically, cooking is performed by adjusting the amount of cooking liquor added. Increase the yield of the resulting pulp with a zipper value of 18 to 3.5% or more with respect to the absolutely dry chips and reduce the active alkali addition rate per absolutely dry chip by 2% or more with respect to the chip weight. Pulp cooking liquor.

すなわち、 本発明に従う蒸解液によれば、 木材チップとして学名 ： F a g u s C r e n a t a B 1 u m eから選ばれるチップを選択した場合に、 通常のクラフ トパルプ （KP) 蒸解を行った場合と比較して、 パルプ収率を 3. 5 %以上向上さ せるという、 これまでにない大きな効果と、 薬液使用量の減少が活性アルカリ添 加率として 2 %以上という大きな効果が同時に、 初めて達成される。 なお、 第一 発明において、 このようにパルプ蒸解液を規定する際に使用する蒸解釜は、 静止釜よ りは回転可能な蒸解釜であるのが好ましい。 第一発明のパルプ蒸解液を用いて、 実際に、 蒸解の原料となる種々のチップを蒸解 した場合、 チップの種類、 性状によりパルプ蒸解液の効果は大きくなつたり、 小さく なったりする力 \ 通常行われている KP蒸解の条件で本発明のパルプ蒸解液を用いれ ば、 これまで以上に、 収率は必ず向上し、 活性アルカリの添加率は必ず減少する。 第一発明のパルプ蒸解液は、 白液と同様、 水酸化ナトリウムと硫化ナトリウムを含 有する力、 多硫化物イオンを含有することが好ましい。 ここで、 多硫化物イオンとはThat is, according to the cooking liquor according to the present invention, when a chip selected from the scientific name: Fagus C renata B 1 ume is selected as a wood chip, compared with a case where ordinary craft pulp (KP) cooking is performed, For the first time, an unprecedented large effect of improving pulp yield by 3.5% or more and a large effect of reducing chemical consumption by 2% or more as an active alkali addition rate are achieved. In the first invention, the digester used for defining the pulp digestion liquid as described above is preferably a rotatable digester rather than a stationary cooker. When various chips, which are used as raw materials for cooking, are actually cooked using the pulp cooking liquor of the first invention, the effect of the pulp cooking liquor increases or decreases depending on the type and properties of the chips. If the pulp cooking liquor of the present invention is used under the conditions of the present KP cooking, the yield will always increase and the addition rate of active alkali will necessarily decrease. Like the white liquor, the pulp cooking liquor of the first invention preferably contains sodium hydroxide and sodium sulfide, and contains polysulfide ions. Here, what is polysulfide ion?

—般式 S で表され単に多硫化物ともいう。 多硫化硫黄とは多硫化物イオン中酸化 数が 0の硫黄で S 中 （X— 1) 個分の硫黄をいう。 また、 N a2S態硫黄とは多硫 化物イオン中酸化数 IIの硫黄 （Sx2 中 1個分の硫黄） と硫化物イオンの総称とす る。 活性アルカリ （以下適宜 「AA」 とも記載する） とは N a OH + N a2Sを N a2 0濃度に換算したものである。 —Represented by the general formula S and simply called polysulfide. Sulfur polysulfide refers to sulfur with an oxidation number of 0 in polysulfide ions and (X-1) sulfur in S. Further, N a The 2 S state sulfur shall be the generic term for sulfide ions and sulfur (Sx 2 in one minute sulfur) of Ta硫hydride ion during the oxidation number II. The active alkali (hereinafter also referred to as "AA") is obtained by converting the N a OH + N a 2 S in N a 2 0 concentration.

第一発明のパルプ蒸解液は、 好ましくは多硫化物ィォンを含有することが好ましい 力 この多硫化物イオンを含有するパルプ蒸解液の製造方法としては、 例えば空気酸 化法や電解法が挙げられる。 空気酸化法は特開昭 6 1 - 2 59754号公報、 特開昭 53 - 9298 1号公報にも記載されているように、 活性炭触媒の存在下、 白液等の 硫化ナトリウムを含有する液を空気と接触させ、 硫化物イオンを酸化させて多硫化物 イオンを生成させるものである。 しかし、 この方法では必然的にチォ硫酸イオンが副 生し、 多硫化物ィォンを構成する多硫化硫黄濃度を大きくすることは比較的困難であ る。 このため、 本発明においては、 空気酸化法で製造してもよいが、 好ましくは電解 法が用いられる。  The pulp cooking liquor of the first invention preferably contains polysulfide ion. Examples of the method for producing the pulp cooking liquor containing polysulfide ions include an air oxidation method and an electrolytic method. . As described in JP-A-61-259754 and JP-A-53-92981, the air oxidation method uses a solution containing sodium sulfide such as white liquor in the presence of an activated carbon catalyst. It comes into contact with air and oxidizes sulfide ions to produce polysulfide ions. However, in this method, thiosulfate ion is inevitably produced as a by-product, and it is relatively difficult to increase the concentration of sulfur polysulfide constituting polysulfide ion. For this reason, in the present invention, it may be produced by an air oxidation method, but preferably, an electrolytic method is used.

第一発明のパルプ蒸解液は 6 gZL以上の多硫化硫黄濃度を含有することが好まし い。 このように多硫化硫黄濃度を高くすることにより、 セルロースの安定化をより促 進させ、 パルプ収率をより向上させることができる。 多硫化硫黄濃度が 6 g/Lに満 たないとパルプ収率の向上効果が小さくなるおそれがある。 より好ましくは 8 g/L 以上である。  The pulp cooking liquor of the first invention preferably contains a sulfur polysulfide concentration of 6 gZL or more. By increasing the sulfur polysulfide concentration in this manner, cellulose stabilization can be further promoted, and the pulp yield can be further improved. If the sulfur polysulfide concentration is less than 6 g / L, the effect of improving pulp yield may be reduced. It is more preferably at least 8 g / L.

多硫化物イオンを含むパルプ蒸解液の製造方法の一つである電解法は、 多硫化硫黄 濃度が 8 gZL以上含有する蒸解液を製造する方法として特に好ましい。 このような 電解法としては、 例えば本発明者らが先に開発した PC Tノ J P 97/01456 , 特願平 1 0— 1 663 74号、 特願平 1 1一 5 1 0 1 6号、 特願平 1 1一 5 1 0 3 3号等の電解法を適用することができる。 電解法によれば、 空気酸化法のように高 濃度の多硫化硫黄濃度を製造するために反応率を上げると、 選択率が低下して蒸解に は無効なチォ硫酸ィォンが多く生成することなく、 従来の方法に比べて高い選択率で 高濃度の多硫化硫黄および N a 2 S態硫黄を含む蒸解液を製造することができる。 それら電解法では、 例えば陽極を備えた陽極室と陰極を備えた陰極室とそれら 2つ の部屋を区画する隔膜を有する電解槽の陽極室に硫化物イオンを含有する溶液、 例え ば白液や緑液を導入して電解酸化することにより多硫化物ィォンを含む蒸解液が得ら れる。 陽極としては耐アルカリ性と耐酸化性をを有することが必要で、 例えば非金属 では炭素材料、 金属ではニッケル、 コバルト、 チタン等の卑金属やそれらの合金およ び酸化物、 あるいは白金、 金、 ロジウム等の責金属やそれらの合金および酸化物等を 用いることができる。 陽極の構造は物理的に 3次元網目構造を有する多孔性構造が好 ましい。 The electrolysis method, which is one of the methods for producing a pulp cooking liquor containing polysulfide ions, is particularly preferable as a method for producing a cooking liquor having a sulfur polysulfide concentration of 8 gZL or more. Examples of such an electrolysis method include, for example, PCT No. JP 97/01456, Japanese Patent Application No. 10-16663 74, Japanese Patent Application No. 111-151016, developed by the present inventors. Japanese Patent Application 1 1 1 5 1 0 33 Electrolysis method such as No. 3 can be applied. According to the electrolysis method, when the reaction rate is increased to produce a high sulfur polysulfide concentration as in the air oxidation method, the selectivity is reduced, and a large amount of thiosulfate, which is ineffective for cooking, is not produced. However, it is possible to produce a cooking liquor containing a high concentration of sulfur polysulfide and Na 2 S-type sulfur with a higher selectivity than the conventional method. In these electrolysis methods, for example, a solution containing sulfide ions, for example, a white liquor or the like in an anode chamber of an electrolytic cell having an anode chamber provided with an anode, a cathode chamber provided with a cathode, and a diaphragm separating the two chambers. By introducing green liquor and performing electrolytic oxidation, a cooking liquor containing polysulfide ion can be obtained. The anode must have alkali resistance and oxidation resistance.For example, nonmetals include carbon materials, metals include base metals such as nickel, cobalt, and titanium, and alloys and oxides thereof, or platinum, gold, and rhodium. And the like, and alloys and oxides thereof. The structure of the anode is preferably a porous structure having a physically three-dimensional network structure.

陰極としては、 耐アルカリ性の材料が好ましく、 ニッケル、 ラネ一ニッケル、 硫化 ニッケル、 鋼、 ステンレス鋼などを用いることができる。 形状は平板またはメッシュ 状の形状のものを、 一つまたは複数を多層構成にして用いる。 線状の電極を複合した 3次元電極を用いることもできる。  As the cathode, an alkali-resistant material is preferable, and nickel, Raney nickel, nickel sulfide, steel, stainless steel, or the like can be used. The shape is a flat plate or a mesh shape, and one or a plurality of them are used in a multilayer structure. A three-dimensional electrode combining linear electrodes can also be used.

陽極室と陰極室とを隔てる膜としては、 カチオン交換膜を用いるのが好ましい。 力 チオン交換膜は、 陽極室から陰極室へはカチオンを導くが、 硫化物イオンおよび多硫 化物イオンの移動を妨げる。 カチオン交換膜として、 炭化水素系またはフッ素系の高 分子に、 スルホン酸基、 カルボン酸基などのカチオン交換基が導入された高分子膜が 好ましい。 また、 耐アルカリ性などの面で問題がなければ、 バイポーラ膜、 ァニオン 交換膜などを使用することもできる。 このような電解槽の陽極室内で、 白液または緑 液の硫化物ィォンの一部を酸化して多硫化物ィオンを生成させ、 蒸解工程に供する。 第一発明のパルプ蒸解液では、 多硫化物イオンを含む場合、 N a 2 S態硫黄濃度が N a 2 0換算で 9 g Z L以上残存していることが好ましい。 この濃度が 9 g / Lに満 たないと多硫化物イオンが不安定になり、 蒸解により得られるパルプのカッパ一価が 上昇したり、 パルプ収率が低下するおそれがぁる。 It is preferable to use a cation exchange membrane as the membrane separating the anode compartment and the cathode compartment. Force cation exchange membranes guide cations from the anodic compartment to the cathodic compartment, but hinder the transfer of sulfide and polysulfide ions. As the cation exchange membrane, a polymer membrane in which a cation exchange group such as a sulfonic acid group or a carboxylic acid group is introduced into a hydrocarbon-based or fluorine-based high molecule is preferable. If there is no problem in terms of alkali resistance or the like, a bipolar membrane, an anion exchange membrane, or the like can be used. In the anode chamber of such an electrolytic cell, a part of the sulfide ion of the white liquor or the green liquor is oxidized to generate a polysulfide ion, which is supplied to the digestion step. The pulp cooking liquor of the first invention, if it contains polysulfide ions, it is preferable that N a 2 S state sulfur concentration remains 9 g ZL more than N a 2 0 conversion. If the concentration is less than 9 g / L, polysulfide ions become unstable, and the kappa monovalent of the pulp obtained by cooking may increase or the pulp yield may decrease.

第一発明の蒸解液はキノン化合物を含有することが好ましい。 キノン化合物として は、 具体的には、 9， 1 0 —アン トラキノン、 2—メチルー 9 , 1 0 —アン トラキノ ン、 2—ェチルー 9， 1 0—アン トラキノン等のアルキルアン トラキノン、 1、 4、 4 a、 9 a—テトラヒ ドロー 9， 1 0—アン トラキノン、 1 , 4ージヒ ドロー 9, 1 0—アン トラキノン、 2— (9， 1 0—アン トラキノィル） 一 1一エタンスルホン酸 、 9， 1 0—アン トラキノンー 2—スルホン酸、 アミノー 9， 1 0—アン トラキノン 等のキノン化合物、 およびこれらの還元体 （ジヒドロ体またはジヒドロ体のナトリウ ム塩） があげられる。 The cooking liquor of the first invention preferably contains a quinone compound. Specific examples of quinone compounds include 9,10-anthraquinone and 2-methyl-9,10-anthraquino Alkyl, anthraquinones such as 2,4-ethyl-9,10-anthraquinone, 1,4,4a, 9a-tetrahydro9,10-anthraquinone, 1,4-dihidro9,10-anthraquinone Quinone compounds such as, 2- (9,10-anthraquinol) -11-ethanesulfonic acid, 9,10-anthraquinone-2-sulfonic acid, amino-9,10-anthraquinone, and their reduced forms ( A dihydro form or a sodium salt of a dihydro form).

これらのキノン化合物を蒸解液に蒸解以前または蒸解直前に添加することにより、 第一発明のパルプ蒸解液として好ましい蒸解液となる力5、 添加する状態は酸化型であ るキノン体でも還元型であるハイ ドロキノン体でもどちらでもよレ、。 また、 添加後の 状態もそのどちらでもよい。 例えば、 1、 4、 4 a、 9 a—テトラヒドロ一 9， 1 0 —アン トラキノンはアルカリ性の蒸解液中では 1， 4—ジヒ ドロ一 9， 1 0—ジヒ ド ロキシアン トラセンジナトリゥム塩になっている。 By adding these quinone compounds digestion before or cooking just prior to the cooking liquor, force 5 to be preferably cooking liquor as the pulp cooking liquor of the first invention, the addition to the state in reduced form in quinone body Ru oxidized der It can be either a hydroquinone body. The state after addition may be either. For example, 1,4,4a, 9a-tetrahydro-9,10-anthraquinone is converted to 1,4-dihydro-19,10-dihydroxy-thracenedinatridium salt in an alkaline cooking liquor. ing.

第一発明のパルプ蒸解液に、 好ましくは含まれるキノン化合物は、 絶乾チップ当り 0. 0 1〜 1. 5重量％になるように蒸解液に存在することが好ましい。 より好まし くは 0. 02〜0. 06重量0 /0である。 キノン化合物の存在量が絶乾チップ当り 0. 0 1重量0 /0未満であれば、 存在量が少なすぎて蒸解後パルプのカッパ一価や AA使用 量が低減されず、 力ッパー価と A A添加率およびパルプ収率の関係が改善されない。 また、 キノン化合物を 1. 5重量％を超えた量でも、 それ以上の蒸解後パルプの力ッ パー価や A A使用量の低減およびカッパ一価とパルプ収率および A A使用量の関係の 改善は認められない。 The quinone compound preferably contained in the pulp cooking liquor of the first invention is preferably present in the cooking liquor such that the quinone compound is contained in an amount of 0.01 to 1.5% by weight per absolutely dried chip. More preferably rather is 0.02 to 0.06 weight 0/0. If abundance 0.0 less than 1 wt 0/0 per bone dry chips quinone compound is not Kappa monovalent or AA usage digestion after pulp abundance is too small can be reduced, the force wrapper value and AA The relationship between the addition rate and the pulp yield is not improved. In addition, even if the amount of the quinone compound exceeds 1.5% by weight, further reduction of the pulp value and AA consumption of the pulp after digestion and improvement of the relation between the kappa monovalent value and the pulp yield and AA consumption are not expected. unacceptable.

第二発明のパルプ蒸解液は、 少なく とも多硫化物イオンを含有する白液又は緑液の うち、 多硫化物イオンを構成する多硫化硫黄濃度が 6 gZL以上で、 絶乾チップ当り 0. 0 1〜 1. 5重量0 /0のキノン化合物を含有している。 この蒸解液に含まれる多硫 化物イオンの製造法は、 第一発明の蒸解液の場合と同様に、 空気酸化法で製造しても よいが、 多硫化物イオンを構成する多硫化硫黄濃度が 6 g/L以上の蒸解液は、 好ま しくは電解法で製造される。 電解法は前述のとおり実施することができる。 多硫化硫 黄濃度を高くすることによ り、 セルロースの安定化をより促進させ、 パルプ収率をよ り向上させることができる。 多硫化硫黄濃度が 6 g/Lに満たないとパルプ収率の向 上効果が小さくなるおそれがある。 より好ましくは 8 g/L以上である。 また、 第二発明のパルプ蒸解液には、 キノン化合物が絶乾チップ当り 0. 0 1〜 1 . 5重量％になるように存在する。 より好ましくは 0. 02〜0. 06重量％である 。 キノン化合物の存在量が絶乾チップ当り 0. 0 1重量％未満であれば、 存在量が少 なすぎて蒸解後パルプの力ッパー価や AA使用量が低減されず、 力ッパー価と AA添 加率およびパルプ収率の関係が改善されない。 また、 キノン化合物が 1. 5重量％を 超えた存在量でも、 それ以上の蒸解後パルプ力ッパー価や A A使用量の低減および力 ッパ一価とパルプ収率および A A使用量の関係の改善は認められない。 キノン化合物 の具体例や存在形態につていは前述第一発明の場合と同様である。 The pulp cooking liquor of the second invention is a white liquor or a green liquor containing at least polysulfide ions, wherein the concentration of sulfur sulfide constituting polysulfide ions is 6 gZL or more and 0.0 per absolutely dry chip. 1 1. contains a quinone compound 5 weight 0/0. The method for producing polysulfide ions contained in the cooking liquor may be an air oxidation method as in the case of the cooking liquor of the first invention, but the concentration of sulfur sulfide constituting the polysulfide ions may be reduced. Cooking liquor above 6 g / L is preferably produced electrolytically. The electrolysis method can be performed as described above. By increasing the sulfur polysulfide concentration, cellulose stabilization can be further promoted, and pulp yield can be further improved. If the sulfur polysulfide concentration is less than 6 g / L, the effect of improving pulp yield may be reduced. More preferably, it is 8 g / L or more. In the pulp cooking liquor of the second invention, the quinone compound is present in an amount of 0.01 to 1.5% by weight per absolutely dry chip. More preferably, it is 0.02 to 0.06% by weight. If the amount of the quinone compound is less than 0.01% by weight based on the absolutely dry chips, the amount of the quinone compound is too small to reduce the pulp power and AA consumption of the pulp after digestion. The relationship between additivity and pulp yield is not improved. In addition, even if the quinone compound is present in an amount exceeding 1.5% by weight, further reduction of pulp power and AA consumption after cooking and improvement of the relationship between pulp yield and pulp yield and AA consumption It is not allowed. Specific examples and forms of the quinone compound are the same as those in the first invention.

第二発明のパルプ蒸解液においても、 第一発明と同様に、 N a2S態硫黄濃度が N a 20換算で 9 gZL以上残存していることが好ましい。 この濃度が 9 g/Lに満た ないと多硫化物イオンが不安定になり、 蒸解により得られるパルプの力ツバ一価が上 昇したり、 パルプ収率が低下するおそれがぁる。 Also in the pulp cooking liquor of the second invention, similar to the first invention, it is preferable that N a 2 S state sulfur concentration remains N a 2 0 translated at 9 GZL above. If this concentration is less than 9 g / L, the polysulfide ions become unstable, and the pulp obtained by cooking may have a higher strength and the pulp yield may be reduced.

第一および第二の発明において、 キノン化合物の添加時期は、 蒸解前または蒸解途 中に一括添加する方法、 あるいは段階的に分割して添加する方法のいずれでも有効で ある。 ただし、 キノン化合物を含む蒸解液がチップ内に十分浸透するように添加する のが好ましい。 本発明の蒸解液を用い、 回分式蒸解釜を用いて蒸解を行う際の液比は 、 絶乾チップ当り 2. 0〜 5. 0 LZk gになるようにするのが好ましい。 より好ま しくは 2. 5〜4. 0 LZk gである。 液比が 2. 0 LZk g未満であると、 蒸解液 がチップに十分に浸透しないことによる蒸解効果の低下のおそれがあるので好ましく ない。 液比が 5. O LZk gを超えると使用薬液量削減効果が低下するので好ましく ない。  In the first and second inventions, the method of adding the quinone compound may be any of a method of adding the compound at one time before or during the cooking or a method of adding the compound in steps. However, it is preferable to add so that the cooking liquor containing the quinone compound sufficiently penetrates into the chips. The cooking liquor of the present invention is preferably used so that the liquor ratio when performing cooking using a batch digester is 2.0 to 5.0 LZkg per absolutely dry chip. More preferably, it is 2.5 to 4.0 LZkg. If the liquid ratio is less than 2.0 LZkg, the cooking liquor may not sufficiently penetrate into the chips, which may reduce the cooking effect, which is not preferable. When the liquid ratio exceeds 5.OLZkg, the effect of reducing the amount of used chemical liquid decreases, which is not preferable.

連続式蒸解釜を用いて蒸解を行う際には、 液比は絶乾チップ当り 1. 5〜 5. 0 L Zk gになるようにするのが好ましい。 より好ましくは 2. 0〜3. 5 L/k gであ る。 液比が 1. 5 L/k g未満であると、 浸透段に気相部が生じ、 蒸解効果が低下す るおそれがあるので好ましくない。 液比が 5. O L/k gを超えると、 使用薬液量削 減効果が低下するので好ましくない。 また、 特にリグノセルロース材料に針葉樹チッ プを用いる場合は 1. 5〜3. 5 L/k g、 広葉樹チップを用いる場合は 2. 5〜5 . 0 L/k gであるとより好ましい。 液比が 1. 5 L/k g未満であると、 アルカリ 性蒸解液がチップに十分に浸透しないことによる蒸解効果が低下するおそれがあるの で好ましくない。 ここで液比とは、 回分式蒸解釜の場合には絶乾チップ重量当り の液量のことをいう力5、 連続式蒸解釜においては、 単位時間当りの釜への絶乾チ ップ流入重量と釜への液体の容積流入量の比をいう。 When cooking is performed using a continuous digester, the liquid ratio is preferably adjusted to 1.5 to 5.0 L Zkg per absolutely dry chip. More preferably, it is 2.0 to 3.5 L / kg. If the liquid ratio is less than 1.5 L / kg, a gas phase is formed in the infiltration stage, and the digestion effect may be reduced, which is not preferable. If the liquid ratio exceeds 5.OL / kg, the effect of reducing the amount of chemical used decreases, which is not preferable. In addition, it is more preferable to use 1.5 to 3.5 L / kg when a softwood chip is used as a lignocellulosic material and 2.5 to 5.0 L / kg when a hardwood chip is used. If the liquid ratio is less than 1.5 L / kg, the cooking effect may be reduced due to insufficient penetration of the alkaline cooking liquor into the chips. Is not preferred. Here, the liquor ratio, refers to a bone-dry chip weight per liquid volume in the case of batch cooker force 5, in the continuous digester, Ze'inuichi-up flowing into the kettle per unit time It refers to the ratio between the weight and the volume of liquid flowing into the kettle.

パルプ蒸解で通常用いられる白液の組成は、 現在行われているクラフトパルプ蒸解 に用いられている白液の場合、 通常、 アルカリ金属イオンとして 2〜6mo 1 ZLを 含有し、 そのうちの 90 %以上はナトリウムイオンであり、 残りはほぼ力リウムィォ ンである。 またァニオンは、 水酸化物イオン、 硫化物イオン、 炭酸イオンを主成分と し、 硫化物イオン濃度は通常 0. 5〜0. 8 mo 1 /Lであり、 他に硫酸イオン、 チ ォ硫酸イオン、 塩素イオン、 亜硫酸イオンを含む。 更にカルシウム、 ケィ素、 アルミ 、 リン、 マグネシウム、 銅、 マンガン、 鉄のような微量成分を含む。 緑液の組成は基 本的に白液と同じである。 ただし、 白液は硫化ナトリウムと水酸化ナトリウムが主成 分であるのに対して、 緑液は硫化ナトリウムと炭酸ナトリゥムが主成分である。  The composition of white liquor usually used in pulp cooking is that white liquor used in current kraft pulp cooking usually contains 2 to 6 mol 1 ZL as alkali metal ions, of which 90% or more Is sodium ion, and the rest is almost force ion. Anions are mainly composed of hydroxide ions, sulfide ions, and carbonate ions.The sulfide ion concentration is usually 0.5 to 0.8 mo1 / L, and sulfate ions and thiosulfate ions are also included. , Including chloride ion and sulfite ion. It also contains trace components such as calcium, silicon, aluminum, phosphorus, magnesium, copper, manganese and iron. The composition of green liquor is basically the same as white liquor. However, while white liquor is mainly composed of sodium sulfide and sodium hydroxide, green liquor is mainly composed of sodium sulfide and sodium carbonate.

本発明のパルプ蒸解液によれば、 リグノセルロース材 である針葉樹または広葉樹 の何れの樹種でも良好な蒸解効果が得られる。 例えば、 針葉樹としては C r y p t 0 m e r i a (スギ）、 P i c e a (ェゾマッ、 トウヒ、 ォゥシユウ トウヒ、 シ トカ ト ゥヒ等）、 P i n u s (ラジア一夕マツ、 ァカマツ、 クロマツ等）、 Th u j a (べィ スギ、 ネズコ等）、 T s u g a (ッガ、 ペイッガ等）、 広葉樹では E u c a 1 y p t u s (ユーカリ類）、 F a g u s (ブナ類）、 Qu e r c u s (ナラ、 カシ等）、 A c a c i a (アカシア類） 等があげられる。 実施例  According to the pulp cooking liquor of the present invention, a good cooking effect can be obtained with any of the lignocellulosic materials, coniferous or hardwood. For example, conifers such as Crypt 0 meria (cedar), P icea (ezoma, spruce, oshuyu spruce, sika pine), Pinus (radius pine, akamatsu, black pine, etc.), Thuja (bay Japanese cedars and cats), T suga (e.g., pegga), hardwoods such as E uca 1 yptus (eucalyptus), Fagus (beech), Quercus (oak, oak, etc.), and Acacia (acacia) Is raised. Example

以下、 実施例に基づき本発明をさらに詳しく説明する力 s、 本発明がこれらの実施例 に限定されないことはもちろんである。 試験法は下記のとおりである。 Hereinafter, the force s which will be described in detail further present invention based on examples, the present invention is not limited to these Examples. The test method is as follows.

《試験法》  《Test method》

得られた未晒しノ、°ルプのノ、°ルプ収率としては、 単繊維化していない柏を除去した精 選パルプの収率を測定した。 未晒しパルプの力ッパー価は、 T A P P I試験法 T 23 6 hm— 85に従って行った。 アルカリ性蒸解液中のチォ硫酸ナトリウム、 Na2S 態硫黄および硫黄換算での多硫化硫黄濃度の定量は特開平 7— 92 1 48号公報に記 載された方法に基づいて行つた。 〈比較例 1 > As the yields of the obtained unbleached pulp and pulp, the yield of the selected pulp from which the non-single fiber kashiwa was removed was measured. The power value of unbleached pulp was determined according to TAPPI test method T236 hm-85. The determination of the concentration of sodium thiosulfate, Na 2 S-form sulfur and sulfur polysulfide in terms of sulfur in the alkaline cooking liquor was carried out based on the method described in JP-A-7-92148. <Comparative Example 1>

オイルバス内で回転可能な蒸解釜を用い、 学名 ： F a g u s C r e n a t a B 1 umeから選ばれた 3 0年生前後のチップのうち、 9 / 8インチ径丸穴篩を通過し 3/1 6ィンチ径丸穴篩を通過しないチップを用い、 水酸化ナトリウム 70 gZLお よび硫化ナトリウム 3 0 gZL、 炭酸ナトリウム 1 5 g/L (いずれも N a 20換算 ) のモデル白液を調製し、 活性アルカリ添加率を 1 4、 1 6、 1 8重量％ (対絶乾チ ップ； N a 20換算） の割合で添加し、 液比を絶乾パルプ重量に対してチップ持ち込 み水分を合わせて 3. 0 k g/Lになるように蒸解液と水を加えた。 室温から 1 60 °Cまで 6 0分で昇温し、 1 60 °Cで 4 1分間維持した。 蒸解後のカツノ、'一価とパルプ 収率は、 次の通りである。 Using a digester that is rotatable in an oil bath, scientific name: Chips of about 30th grade selected from Fagus C renata B 1 ume passed through a 9/8 inch diameter round hole sieve and 3/16 inch using a chip which does not pass through the neck round Anafurui, model white liquor was prepared of sodium hydroxide 70 GZL Contact and sodium sulfide 3 0 GZL, sodium carbonate 1 5 g / L (both N a 2 0 equivalent), the active alkali the addition of 1 4, 1 6, 1 8% by weight; was added at a rate of (vs. Ze'inuichi-up N a 2 0 equivalent), the combined chip retention write-water liquid ratio to absolute dry pulp weight The digestion liquor and water were added to 3.0 kg / L. The temperature was raised from room temperature to 160 ° C. in 60 minutes and maintained at 160 ° C. for 41 minutes. Katsuno, 'monovalent and pulp yield after cooking are as follows.

A A添加率％ 力ッパ —価 パルプ収率％  A A addition rate% Power pulp value Pulp yield%

1 4 2 9. 6 53. 3  1 4 2 9. 6 53.3

1 6 2 0. 4 5 1. 7  1 6 2 0.4 5 1.7

1 6 1 9. 6 50. 7  1 6 1 9. 6 50. 7

1 8 1 6. 2 4 9. 1  1 8 1 6. 2 4 9. 1

1 8 1 6. 1 4 9. 8  1 8 1 6. 1 4 9.8

これらのデータから、 カッパ一価 1 8でのパルプ収率は 50 · 3%、 AA添加率は 1 7. 0 %であった。  From these data, the pulp yield at kappa monovalent 18 was 50 · 3% and the AA addition rate was 17.0%.

〈比較例 2 >  <Comparative Example 2>

比較例 1 と同様のチップを用い、 蒸解液は比較例 1の組成のモデル白液を活性炭触 媒で空気酸化した多硫化物溶液を想定し、 反応率 60%、 選択率 63%を仮定し、 水 酸化ナトリウム 70 gZL、 N a 2 S態ィォゥ 1 2. 0 g/L, 炭酸ナトリウム 1 5 g/Lおよびチォ硫酸ナトリウム 3. 3 g/ (いずれも N a 20換算）、 多硫化硫黄 5. 9 g/ (硫黄換算） のモデル多硫化物蒸解液を調製した。 酸化する前の白液に 換算した活性アルカリ添加率を 1 5重量％、 1 7重量％、 1 9重量％ (対絶乾チップ ； N a20換算） の割合で添加し、 比較例 1 と同様に、 液比を絶乾パルプ重量に対し てチップ持ち込み水分を合わせて 3. 0 k g/Lになるように蒸解液と水を加えた。 比較例 1 と同様の温度条件で蒸解を行った。 蒸解後のカッパ一価とパルプ収率は、 次 の通りである。 A A添加率％ 力ッパー価 パルプ収率％ Using the same chips as in Comparative Example 1, the cooking liquor is assumed to be a polysulfide solution obtained by oxidizing the model white liquor of the composition of Comparative Example 1 with activated carbon catalyst, and assuming a reaction rate of 60% and a selectivity of 63%. , Sodium hydroxide 70 gZL, Na 2 S form 12.0 g / L, sodium carbonate 15 g / L and sodium thiosulfate 3.3 g / (all converted to Na 20 ), sulfur polysulfide 5.9 g / (sulfur conversion) model polysulfide cooking liquor was prepared. 1 5% by weight of active alkali addition rate in terms of white liquor prior to the oxidation, 1 7 wt%, 1 9% by weight; was added at a rate of (vs. bone-dry chip N a 2 0 equivalent), and Comparative Example 1 Similarly, the digestion liquor and water were added so that the liquid ratio became 3.0 kg / L in total with the water brought in chips with respect to the absolutely dry pulp weight. The digestion was performed under the same temperature conditions as in Comparative Example 1. The kappa monovalent value and pulp yield after cooking are as follows. AA addition rate% Power value Pulp yield%

1 5 26. 7 54. 1  1 5 26. 7 54. 1

1 7 1 9. 5 52. 1  1 7 1 9. 5 52. 1

1 9 1 5. 8 49. 7  1 9 1 5.8 49.7

これらのデータから、 カッパ一価 1 8でのパルプ収率は 5 1. 0%、 AA添加率は 1 7. 9 %であった。  Based on these data, the pulp yield at kappa monovalent of 18 was 51.0% and the AA addition rate was 17.9%.

〈比較例 3 >  <Comparative Example 3>

比較例 1と同様のチップを用い、 蒸解液は以下の構成の電解槽で以下の条件で製造 した。  Using the same chips as in Comparative Example 1, a cooking liquor was produced in an electrolytic cell having the following configuration under the following conditions.

ァノ一 ド集積体にニッケル板、 アノー ドにニッケル発泡体 （ 1 0 0 m m X 2 0 mm X 4 mm、 網目の平均孔径 0. 5 1 mm、 アノード室体積当りのアノード表 面積： 5 6 0 0 m2Zm3、 隔膜面積に対する表面積 ： 2 8 m2/m2)、 力ソード として鉄のェクスパンジョンメタル、 隔膜としてフッ素樹脂系カチオン交換膜と からなる 2室型の電解槽を組み立てた。 ァノ一ド室は高さ 1 0 0 mm、 幅 20 m m、 厚み 4 mmであり、 力ソー ド室は高さ 1 00mm、 幅 2 0 mm、 厚み 5mm で、 隔膜の有効面積は 2 0 c m2であった。 比較例 1で使用した白液を用い、 ァ ノ―ド液線速度 ： 4 c mZ s e c、 電流密度 ： 6 k A7m2、 電解温度 ： 9 0 °C にて循環電解を行い、 硫化ナトリゥムの反応率 ： 5 5 %、 選択率 ： 9 5 %で次の 組成の多硫化物蒸解液を得た。 Nickel plate on anode stack, nickel foam on anode (100 mm x 20 mm x 4 mm, average mesh diameter of 0.5 mm, anode surface area per anode chamber volume: 56 0 m 2 Zm 3 , surface area with respect to the diaphragm area: 28 m 2 / m 2 ), a two-chamber electrolytic cell composed of iron expansion metal as a force source and a fluororesin cation exchange membrane as a diaphragm Assembled. The anode chamber is 100 mm high, 20 mm wide and 4 mm thick.The force source chamber is 100 mm high, 20 mm wide and 5 mm thick, and the effective area of the diaphragm is 20 cm. Was 2 . Using the white liquor used in Comparative Example 1, anodic liquid linear velocity: 4 cmZ sec, current density: 6 kA7 m 2 , electrolysis temperature: 90 ° C, circulating electrolysis was performed, and sodium sulfide was reacted. A polysulfide digest having the following composition was obtained at a rate of 55% and a selectivity of 95%.

水酸化ナ ト リ ウム 7 0 g/L (Na20換算） Hydroxide Na Application Benefits um 7 0 g / L (Na 2 0 equivalent)

N a 2 S態硫黄 1 3. 5 g/L (N a20換算） 炭酸ナ ト リ ウム 1 5 g/L (Na20換算） N a 2 S state sulfur 1 3. 5 g / L (N a 2 0 equivalent) carbonate Na Application Benefits um 1 5 g / L (Na 2 0 equivalent)

チォ硫酸ナト リ ウム 0. 8 g/L (Na20換算） Chio sulfate isocyanatomethyl Li um 0. 8 g / L (Na 2 0 equivalent)

多硫化硫黄 8. 1 g/L (硫黄換算）  Sulfur polysulfide 8.1 g / L (sulfur conversion)

活性アル力リ添加率を 1 5重量％、 1 7重量％、 1 9重量％ (対絶乾チップ； N a 20換算） の割合で蒸解液を添加し、 比較例 1と同様に、 液比を絶乾パルプ重量に対 してチップ持ち込み水分を合わせて 3. 0 k g/Lになるように蒸解液と水を加えた 。 比較例 1と同様の温度条件で蒸解を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。 A A添加率0 /o カッパ一価 パルプ収率％ The active Al power Li addition of 1 5 wt%, 1 7%, 1 9% by weight; the addition of cooking liquor in a ratio of (vs. bone-dry chip N a 2 0 equivalent), in the same manner as in Comparative Example 1, the liquid The cooking liquor and water were added so that the ratio of the water brought in chips to the absolutely dried pulp weight was 3.0 kg / L. The digestion was performed under the same temperature conditions as in Comparative Example 1. The kappa monovalent value and pulp yield after cooking are as follows. AA addition rate 0 / o Kappa monovalent pulp yield%

1 5 2 1. 2 5 3. 9  1 5 2 1. 2 5 3. 9

1 7 1 7. 6 5 1. 9  1 7 1 7. 6 5 1. 9

1 9 1 3. 7 5 0. 1  1 9 1 3. 7 5 0.1

これらのデータから、 カッパ一価 1 8でのパルプ収率は 52. 3%、 AA添加率は 1 6. 6 %であった。  Based on these data, the pulp yield at kappa monovalent of 18 was 52.3% and the AA addition rate was 16.6%.

〈比較例 4〉  <Comparative Example 4>

比較例 1 と同様のチップを用い、 蒸解液は比較例 3と同様にして製造し、 反応率 6 8 %、 選択率 95 %で以下の組成の多硫化物蒸解液を得た。  Using the same chips as in Comparative Example 1, a cooking liquor was produced in the same manner as in Comparative Example 3, and a polysulfide cooking liquor having the following composition with a conversion of 68% and a selectivity of 95% was obtained.

水酸化ナ ト リ ウム 7 0 g/L (N a 20換算） Hydroxide Na Application Benefits um 7 0 g / L (N a 2 0 equivalent)

N a 2 S態硫黄 9. 6 gZL (N a 20換算） N a 2 S state sulfur 9. 6 gZL (N a 2 0 equivalent)

炭酸ナト リ ウム 1 5 gZL (Na20換算） Carbonate isocyanatomethyl Li um 1 5 gZL (Na 2 0 equivalent)

チォ硫酸ナトリウム 1. 0 g/L (N a 20換算） Chio sodium sulfate 1. 0 g / L (N a 2 0 equivalent)

多硫化硫黄 1 0. 0 g/ (硫黄換算）  Sulfur polysulfide 10.0 g / (sulfur conversion)

活性アル力リ添加率を 1 5重量％、 1 7重量％、 1 9重量％ (対絶乾チップ； N a 20換算） の割合で蒸解液を添加し、 比較例 1 と同様に液比を絶乾パルプ重量に対し てチップ持ち込み水分を合わせて 3. 0 k gZLになるように蒸解液と水を加えた。 比較例 1 と同様の温度条件で蒸解を行った。 蒸解後のカッパ一価とパルプ収率は、 次 の通りである。 The active Al power Li addition of 1 5 wt%, 1 7%, 1 9% by weight; the addition of cooking liquor in a ratio of (vs. bone-dry chip N a 2 0 equivalent), liquor ratio as in Comparative Example 1 The cooking liquor and water were added to bring the total amount of water brought into chips to the absolutely dry pulp weight to 3.0 kg ZL. The digestion was performed under the same temperature conditions as in Comparative Example 1. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率％ 力ッパ一価 パルプ収率％  A A addition rate% Monovalent pulp Pulp yield%

1 5 2 1. 1 54. 2  1 5 2 1. 1 54. 2

1 7 1 6. 0 5 2. 0  1 7 1 6. 0 5 2.0

1 9 1 3. 7 50. 7  1 9 1 3. 7 50. 7

これらのデータから、 カッパ一価 1 8でのパルプ収率は 52 9%、 A A添加率は 1 6. 2 %であった。  From these data, the pulp yield at kappa monovalent 18 was 529% and the AA addition rate was 16.2%.

〈比較例 5〉  <Comparative Example 5>

比較例 2の蒸解液に 1， 4ージヒドロー 9， 1 0—ジヒドロキシアントラセンジナ トリウム塩を絶乾チップ当り 0. 0 5重量0 /0 (アントラキノン換算） 添加した蒸解液 を用いた以外は比較例 2と同様の実験を行った。 蒸解後の力ッパー価とパルプ収率は 、 次の通りである。 1 to the cooking liquor of Comparative Example 2, 4 Jihidoro 9, 1 0 0.0 5 wt absolute dry chips per dihydroxy anthracene Gina thorium salt 0/0 except for using (anthraquinone conversion) the added cooking liquor Comparative Example 2 The same experiment was performed. The power value and pulp yield after cooking are It is as follows.

A A添加率％ 力ッパ一価 パルプ収率％  A A addition rate% Monovalent pulp Pulp yield%

1 5 2 9. 4 5 5. 8  1 5 2 9. 4 5 5.8

1 7 1 7. 6 53. 1  1 7 1 7. 6 53.1

1 9 1 4. 7 52. 5  1 9 1 4. 7 52. 5

これらのデータから、 カッパ一価 1 8でのパルプ収率は 53 4%、 A A添加率は 1 5. 4 %であった。  Based on these data, the pulp yield at kappa monovalent of 18 was 534%, and the AA addition rate was 15.4%.

《実施例 1》  << Example 1 >>

比較例 3の蒸解液に 1 , 4ージヒドロー 9， 1 0—ジヒドロキシアントラセンジナ トリゥム塩を絶乾チップ当り 0. 0 5重量0 /0 (アントラキノン換算） 添加し、 活性ァ ルカリ添加率を 1 3重量0 /0、 1 5重量％、 1 7重量％ (対絶乾チップ； N a 20換算 ) の割合で蒸解液を添加した以外は比較例 3と同様の実験を行った。 蒸解後のカッパ 一価とパルプ収率は、 次の通りである。 1 to the cooking liquor of Comparative Example 3, 4 Jihidoro 9, 1 0-dihydroxy anthracene Gina Toriumu salt per absolutely dried chip 0.0 5 wt 0/0 (anthraquinone equivalent) was added, 1 3 weight active § alkali addition rate It was subjected to the same experiment as Comparative example 3 except for adding cooking liquor at the rate of; (N a 2 0 in terms of pairs absolute dry chips) 0/0, 1 5 wt%, 1 7% by weight. Kappa monovalent after cooking and pulp yield are as follows.

A A添加率 % カッパ一価 ノ、°ルプ収率％  A A addition rate% Kappa monovalent, ° Loop yield%

1 3 2 3. 0 5 5. 7  1 3 2 3. 0 5 5. 7

1 5 1 6. 7 54. 0  1 5 1 6. 7 54. 0

1 7 1 3. 8 52. 5  1 7 1 3.8 52.5

これらのデータから、 カッパ一価 1 8でのパルプ収率は 54. 3%、 AA添加率は 1 4. 6%であった。  Based on these data, the pulp yield at kappa monovalent of 18 was 54.3% and the AA addition rate was 14.6%.

《実施例 2》  << Example 2 >>

比較例 4の蒸解液に 1， 4ージヒドロー 9， 1 0—ジヒドロキシアントラセンジナ トリゥム塩を絶乾チップ当り 0. 0 5重量0 /0 (アントラキノン換算） 添加し、 活性ァ ルカリ添加率を 1 3重量0 /0、 1 5重量％、 1 7重量％ (対絶乾チップ； N a 20換算 ) の割合で蒸解液を添加した以外は比較例 4と同様の実験を行った。 蒸解後のカッパ 一価とパルプ収率は、 次の通りである。 1 to the cooking liquor of Comparative Example 4, 4 Jihidoro 9, 1 0-dihydroxy anthracene Gina Toriumu salt per absolutely dried chip 0.0 5 wt 0/0 (anthraquinone equivalent) was added, 1 3 weight active § alkali addition rate It was subjected to the same experiment as Comparative example 4 except for adding cooking liquor at the rate of; (N a 2 0 in terms of pairs absolute dry chips) 0/0, 1 5 wt%, 1 7% by weight. Kappa monovalent after cooking and pulp yield are as follows.

添加率％ 力ッノヽ。一価 パルプ収率％  Addition rate% Monovalent pulp yield%

1 3 20. 5 5 5. 6  1 3 20. 5 5 5. 6

1 5 1 5. 6 54. 0  1 5 1 5. 6 54. 0

1 7 1 2. 6 52. 6 これらのデータから、 カッパ一価 1 8でのパルプ収率は 54. 9%、 AA添加率は 1 3. 9 %であった。 1 7 1 2.6 52. 6 Based on these data, the pulp yield at Kappa monovalent 18 was 54.9% and the AA addition rate was 13.9%.

以上、 実施例 1、 2で用いた蒸解液は、 比較例 1〜 5で用いた蒸解液に比較して同 じ力ッパー価のパルプで比較した場合、 収率がいずれも高く、 活性アル力リ添加率も 低い。 また、 標準チップと標準蒸解条件で蒸解を行った比較例 1 と比べて、 実施例 1 ， 2はカッパ一価 1 8のパルプで比較したとき、 収率は絶乾チップに対して 3. 5 % 以上上昇し、 活性アルカリ添加率も絶乾チップに対して 2%以上減少している。 なお 、 比較例 1が本発明の蒸解液を規定するための標準蒸解条件の一つに位置づけられる 以下に記載する比較例および実施例は、 比較例 1〜 5および実施例 1、 2で実施し た蒸解と同じ蒸解条件で同じ蒸解液を用いて、 別の種類の木材に適用した例である。 〈比較例 6 >  As described above, the cooking liquors used in Examples 1 and 2 showed higher yields and higher active alkanol power when compared with the cooking pulp having the same strength as the cooking liquors used in Comparative Examples 1 to 5. The re-addition rate is also low. In comparison with Comparative Example 1 in which standard chips were digested under standard digestion conditions, Examples 1 and 2 showed a 3.5% yield when compared with absolutely dry chips when kappa monovalent pulp was compared. %, And the active alkali addition rate has decreased by more than 2% with respect to the dry chips. Note that Comparative Example 1 is positioned as one of the standard cooking conditions for defining the cooking liquor of the present invention.Comparative Examples and Examples described below were performed in Comparative Examples 1 to 5 and Examples 1 and 2. This is an example in which the same cooking liquor is used under the same cooking conditions as that of a conventional cooking and applied to different types of wood. <Comparative Example 6>

チリ産のュ一力リ（学名： E u c a l y p t u s S p e c i e s) を用い、 比較例 1と同様の蒸解液を、 その添加量を以下の活性アル力リ添加率 （対絶乾チップ； N a 20換算） で添加した以外は比較例 1 と同様の実験を行った。 蒸解後のカッパ一価と パルプ収率は、 次の通りである。 Using a chili product (scientific name: Eucalyptus Species), the same amount of cooking liquor as in Comparative Example 1 was added at the following addition rate of active alcohol (to absolutely dry chips; Na 20 The same experiment as in Comparative Example 1 was performed, except that it was added in (conversion). The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率％ 力ッパ—価 パルプ収率％  A A addition rate% Power value Pulp yield%

1 2 2 7 . 9 58. 0  1 2 2 7. 9 58. 0

1 3 2 3 . 4 56. 0  1 3 2 3. 4 56. 0

1 4 1 7 . 5 54. 7  1 4 1 7 .5 54.7

1 6 1 3 . 8 53. 6  1 6 1 3. 8 53. 6

1 8 1 3 . 1 5 1. 7  1 8 1 3. 1 5 1. 7

22 1 0 . 1 50. 8  22 1 0 .1 50.8

22 1 0 . 6 5 0. 3  22 1 0 .6 5 0.3

これらのデータから、 カッパ一価 1 8でのパルプ収率は 54. 6%、 AA添加率は 1 4. 8 %であった。  Based on these data, the pulp yield at 18 kappa monovalent was 54.6% and the AA addition rate was 14.8%.

〈比較例 7〉  <Comparative Example 7>

木材チップとして比較例 6同様のチリユーカリチップを用い、 比較例 2と同様の蒸 解液を、 以下の活性アルカリ添加率 （対絶乾チップ； N a20換算） で添加した以外 は比較例 2と同様の実験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りで ある。 With Comparative Example 6 Similar dust eucalyptus chips as wood chips, the same steam solution liquid and Comparative Example 2, the following active alkali addition rate; except for adding at (vs. bone-dry chip N a 2 0 equivalent) Performed the same experiment as Comparative Example 2. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率％ 力ッパー価 パルプ収率％  A A addition rate% Power value Pulp yield%

1 2. 5 2 8. 9 58. 3  1 2. 5 2 8. 9 58.3

1 4. 5 1 9. 3 5 6. 2  14.5 19.3 36.2

1 6. 5 1 5. 0 5 5. 3  16.5 15.0 0 55.3

これらのデータから、 カッパ一価 1 8でのパルプ収率は 5 6 0%、 A A添加率は 1 5. 2 %であった。  Based on these data, the pulp yield at Kappa monovalent 18 was 560% and the AA addition rate was 15.2%.

〈比較例 8〉 <Comparative Example 8>

比較例 6と同様の木材チップを用い、 比較例 3と同様の蒸解液を用い、 比較例 3と 同様の実験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。  The same experiment as in Comparative Example 3 was performed using the same wood chips as in Comparative Example 6 and using the same cooking liquor as in Comparative Example 3. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率 % カッパ一価 ノ、°ルプ収率％  A A addition rate% Kappa monovalent, ° Loop yield%

1 2. 5 23. 7 58. 3  1 2.5 23.7 58.3

1 4. 5 1 4. 8 5 7. 1  14.5 14.8 57.1

1 6. 5 1 3. 7 5 5. 3  1 6.5 1 3. 7 5 5.3

これらのデータから、 カッパ一価 1 8でのパルプ収率は 56. 8%、 AA添加率は 1 4. 3 %であった。  Based on these data, the pulp yield at kappa monovalent of 18 was 56.8% and the AA addition rate was 14.3%.

〈比較例 9〉 <Comparative Example 9>

比較例 6と同様の木材チップを用い、 比較例 4と同様の蒸解液を用い、 比較例 4と 同様の実験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。  The same experiment as in Comparative Example 4 was performed using the same wood chips as in Comparative Example 6 and using the same cooking liquor as in Comparative Example 4. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率0 /0 カッパ一価 パルプ収率％ AA addition rate 0/0 Kappa monovalent pulp yield%

1 2. 5 2 5. 3 58. 5  1 2.5 2 5.3 58.5

1 4. 5 1 4. 9 5 7. 0  1 4.5 1 4. 9 5 7.0

1 6. 5 1 4. 7 54. 7  16.5 14.7 74.7

これらのデータから、 カッパ一価 1 8でのパルプ収率は 57. 2%、 AA添加率は 1 4 · 0%であった。  Based on these data, the pulp yield at kappa monovalent of 18 was 57.2% and the AA addition rate was 14.0%.

〈比較例 1 0〉 比較例 6と同様の木材チップを用い、 比較例 5と同様の蒸解液を用い、 比較例 5と 同様の実験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。 <Comparative Example 10> The same experiment as in Comparative Example 5 was performed using the same wood chips as in Comparative Example 6 and using the same cooking liquor as in Comparative Example 5. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率％ カッパ一価 パルプ収率％  A A addition rate% Kappa monovalent Pulp yield%

1 2 2 1. 0 58. 9  1 2 2 1.0 58.9

1 3. 2 1 5. 1 5 7. 9  1 3. 2 1 5. 1 5 7. 9

1 5 1 3. 5 5 6. 1  1 5 1 3.5 5 6.1

これらのデータから、 カッパ一価 1 8でのパルプ収率は 58. 2%、 AA添加率は 1 2. 7 %であった。  Based on these data, the pulp yield at 18 kappa monovalent was 58.2% and the AA addition rate was 12.7%.

《実施例 3》  << Example 3 >>

比較例 6と同様の木材チップを用い、 実施例 1 と同様の蒸解液を用い、 実施例 1 と 同様の実験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。  The same experiment as in Example 1 was performed using the same wood chips as in Comparative Example 6 and the same cooking liquor as in Example 1. The kappa monovalent value and pulp yield after cooking are as follows.

添加率％ カッパ一価 パルプ収率％  Addition rate% Kappa monovalent pulp yield%

1 2 2 0. 9 58. 7  1 2 2 0.9 58.7

1 3. 2 1 2. 8 5 7. 5  1 3.2 1 2. 8 5 7.5

1 5 1 2. 1 5 7. 1  1 5 1 2. 1 5 7. 1

これらのデータから、 カッパ一価 1 8でのパルプ収率は 5 S . 3%、 AA添加率は 1 2. 3 %であった。  From these data, the pulp yield at Kappa monovalent 18 was 5 S. 3% and the AA addition rate was 12.3%.

《実施例 4》  << Example 4 >>

比較例 6と同様の木材チップを用い、 実施例 2と同様の蒸解液を用い、 実施例 2と 同様の実.験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。  The same experiment as in Example 2 was performed using the same wood chips as in Comparative Example 6 and using the same cooking liquor as in Example 2. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率％ カッパ一価 パルプ収率 %  A A content% Kappa monovalent Pulp yield%

1 2 1 9. 3 58. 9  1 2 1 9. 3 58. 9

1 3. 2 1 4. 9 5 7. 4  1 3. 2 1 4. 9 5 7. 4

1 5 1 2. 9 5 5. 9  1 5 1 2.9 5 5.9

これらのデータから、 カッパ一価 1 8でのパルプ収率は 58. 6%、 AA添加率は 1 2. 3 %であった。  From these data, the pulp yield at Kappa monovalent 18 was 58.6% and the AA addition rate was 12.3%.

以上、 比較例 6〜 1 0および実施例 3、 4で示したチリ産のユーカリチップの例か ら、 比較例 1〜5および実施例 1、 2の標準条件で規定した本発明に従う蒸解液を別 種類の木材チップに適用しても効果が確認された。 同じ力ツバ一価のパルプで比較す ると、 比較例 6〜 1 0で用いた蒸解液よりも実施例 3、 4で用いた蒸解液の方がパル プ収率が高く、 活性ァル力リ添加率が低くなつている。 From the above examples of eucalyptus chips from Chile shown in Comparative Examples 6 to 10 and Examples 3 and 4, the cooking liquor according to the present invention defined under the standard conditions of Comparative Examples 1 to 5 and Examples 1 and 2 was used. The effect was confirmed even when applied to different types of wood chips. Compare with the same strength pulp As a result, the cooking liquors used in Examples 3 and 4 had higher pulp yields and a lower addition rate of active alkali than the cooking liquors used in Comparative Examples 6 to 10.

〈比較例 1 1 >  <Comparative Example 1 1>

ィンドネシァ産アカシア （学名 ： A c a c i a ma n g i um) を用い、 比較例 1 と同様の蒸解液を、 その添加量を以下の活性アル力リ添加率 （対絶乾チップ； N a 2〇換算） で添加した以外は比較例 1 と同様の実験を行った。 蒸解後のカッパ一価と パルプ収率は、 次の通りである。 Indoneshia producing Acacia (scientific name: A cacia ma ngi um) using the same cooking liquor as in Comparative Example 1, the amount less active Al power Li addition ratio; In (vs. bone-dry chip N a 2 〇 equivalent) The same experiment as in Comparative Example 1 was performed, except that it was added. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率％ 力ッパー価 パルプ収率％  A A addition rate% Power value Pulp yield%

1 6 2 9. 1 54. 8  1 6 2 9. 1 54. 8

1 8 2 4. 6 52. 2  1 8 2 4. 6 52. 2

20 2 3. 0 50. 0  20 2 3.0 50. 0

22 1 8. 1 49. 4  22 1 8. 1 49. 4

これらのデータから、 カッパ一価 1 8でのパルプ収率は 4 9 1 %、 A A添加率は 22. 0%であった。  From these data, the pulp yield at kappa monovalent 18 was 491% and the AA addition rate was 22.0%.

〈比較例 1 2 >  <Comparative Example 1 2>

比較例 1 1 と同様の木材チップを用い、 比較例 2と同様の蒸解液を用い、 比較例 2 と同様の実験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。  The same experiment as in Comparative Example 2 was performed using the same wood chips as in Comparative Example 11 and the same cooking liquor as in Comparative Example 2. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率 % カッパ一価 パルプ収率 %  A A addition rate% Kappa monovalent pulp yield%

1 9. 5 2 2. 0 53. 3  19.5 22.0 53.3

2 1. 5 1 6. 9 50. 6  2 1.5 1 6. 9 50. 6

2 3 1 6. 3 5 1. 9  2 3 1 6. 3 5 1. 9

これらのデータから、 カッパ一価 1 8でのパルプ収率は 5 1. 8%、 AA添加率は 2 1. 5 %であった。  Based on these data, the pulp yield at Kappa monovalent 18 was 51.8% and the AA addition rate was 21.5%.

〈比較例 1 3 >  <Comparative Example 13>

比較例 1 1と同様の木材チップと比較例 3と同様の蒸解液を用い、 比較例 3と同様 の実験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。  The same experiment as in Comparative Example 3 was performed using the same wood chips as in Comparative Example 11 and the same cooking liquor as in Comparative Example 3. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率％ カッパ一価 パルプ収率％  A A addition rate% Kappa monovalent Pulp yield%

1 9. 5 1 8. 5 53. 6  19.5 18.5 53.6

2 1. 5 1 4. 9 52. 3 23 1 5. 0 5 1. 0 2 1.5 1 4. 9 52. 3 23 1 5. 0 5 1. 0

これらのデータから、 カッパ一価 1 8でのパルプ収率は 53. 4%、 AA添加率は 1 9. 5 %であった。  Based on these data, the pulp yield at kappa monovalent of 18 was 53.4% and the AA addition rate was 19.5%.

〈比較例 1 4 >  <Comparative Example 14>

比較例 1 1 と同様の木材チップと比較例 4と同様の蒸解液を用い、 比較例 4と同様 の実験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。  The same experiment as in Comparative Example 4 was performed using the same wood chips as in Comparative Example 11 and the same cooking liquor as in Comparative Example 4. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率0 /0 カッパ一価 パルプ収率 % AA addition rate 0/0 Kappa monovalent pulp yield%

1 9. 5 1 7. 5 53. 9  19.5 17.5 53.9

2 1. 5 1 4. 7 52. 3  2 1.5 1 4. 7 52. 3

23 1 4. 1 5 1. 7  23 1 4. 1 5 1. 7

これらのデータから、 カッパ一価 1 8でのパルプ収率は 54. 1 %、 AA添加率は 1 9. 0 %であった。  From these data, the pulp yield at kappa monovalent of 18 was 54.1% and the AA addition rate was 19.0%.

〈比較例 1 5 >  <Comparative Example 15>

比較例 1 1 と同様の木材チップと比較例 5と同様の蒸解液を用い、 比較例 5と同様 の実験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。  The same experiment as in Comparative Example 5 was performed using the same wood chips as in Comparative Example 11 and the same cooking liquor as in Comparative Example 5. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率 % カッパ一価 パルプ収率％  A A addition rate% Kappa monovalent pulp yield%

1 7. 5 2 1. 3 54. 5  1 7.5 2 1. 3 54.5

1 9. 3 1 5. 5 54. 4  19.3 35.5.54.4

2 1. 5 1 4. 7 52. 1  2 1.5 1 4. 7 52. 1

これらのデータから、 カッパ一価 1 8でのパルプ収率は 53. 9%、 AA添加率は 1 8. 7%であった。  Based on these data, the pulp yield at 18 kappa monovalent was 53.9% and the AA addition rate was 18.7%.

《実施例 5》  << Example 5 >>

比較例 1 1 と同様の木材チップと実施例 1 と同様の蒸解液を用い、 実施例 1と同様 の実験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。  The same experiment as in Example 1 was performed using the same wood chips as in Comparative Example 11 and the same cooking liquor as in Example 1. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率0 /0 カッパ一価 パルプ収率％ AA addition rate 0/0 Kappa monovalent pulp yield%

1 7. 5 1 8. 1 5 5. 4  1 7. 5 1 8. 1 5 5. 4

1 9. 3 1 4. 9 54. 1  1 9. 3 1 4. 9 54. 1

2 1. 5 1 3. 5 52. 6  2 1.5 1 3.5 52.6

これらのデータから、 カッパ一価 1 8でのパルプ収率は 55. 5%、 AA添加率は 1 7. 4 %であった。 Based on these data, the pulp yield at kappa monovalent 18 was 55.5% and the AA addition rate was It was 17.4%.

《実施例 6》  << Example 6 >>

比較例 1 1 と同様の木材チップと実施例 2と同様の蒸解液を用い、 実施例 2と同様 の実験を行った。 蒸解後のカッパ一価とパルプ収率は、 次の通りである。  The same experiment as in Example 2 was performed using the same wood chips as in Comparative Example 11 and the same cooking liquor as in Example 2. The kappa monovalent value and pulp yield after cooking are as follows.

A A添加率0 /0 カッパ一価 パルプ収率％ AA addition rate 0/0 Kappa monovalent pulp yield%

1 7. 5 1 8. 2 5 5. 0  17.5 18.2 55.0

1 9. 3 1 5. 7 54. 2  19.3 3 15.7 75.2

2 1. 5 1 3. 1 53. 8  2 1.5 1 3. 1 53. 8

これらのデータから、 カッパ一価 1 8でのパルプ収率は 5 5. 0%、 AA添加率は 1 7. 6 %であった。  From these data, the pulp yield at kappa monovalent of 18 was 55.0% and the AA addition rate was 17.6%.

以上、 比較例 1 1〜 1 5および実施例 5、 6で示したイン ドネシア産アカシアチッ プの例から、 比較例 1〜 5および実施例 1、 2の標準条件で規定した本発明に従う蒸 解液を別種類の木材チップに適用しても効果が確認された。 同じ力ツバ一価のパルプ で比較すると、 比較例 1 1〜 1 5で用いた蒸解液よりも実施例 5、 6で用いた蒸解液 の方がパルプ収率が高く、 活性ァル力リ添加率が低くなつている。 産業上の利用の可能性  As described above, from the examples of Indonesian acacia chips shown in Comparative Examples 11 to 15 and Examples 5 and 6, the cooking liquor according to the present invention defined under the standard conditions of Comparative Examples 1 to 5 and Examples 1 and 2 was used. The effect was confirmed by applying to other types of wood chips. Comparing the pulp with the same strength, monovalent pulp, the cooking liquors used in Examples 5 and 6 had higher pulp yields than the cooking liquors used in Comparative Examples 11 to 15, The rate is getting lower. Industrial applicability

本発明のパルプ蒸解液を用いることにより、 また本パルプ蒸解液を用いるパルプ製 造法により、 パルプ収率を一層向上させ、 カッパ一価とパルプ収率の関係を更に改善 することができる。 すなわち、 本発明によれば、 同一活性アルカリ添加率における力 ッパ一価を減少させ、 かつ同一力ッパー価におけるパルプ収率を向上させるのに優れ ており、 併せて薬液使用量の削減効果、 回収ボイラーの負荷低減効果が達成される。 しかも、 パルプ工場内の薬液回収バランスを崩すことなく、 これらの効果を達成する ことができる。  By using the pulp cooking liquor of the present invention and the pulp manufacturing method using the pulp cooking liquor, the pulp yield can be further improved, and the relationship between monovalent kappa and pulp yield can be further improved. That is, according to the present invention, the pulp monovalent value at the same active alkali addition rate is reduced, and the pulp yield is improved at the same motive power value. The effect of reducing the load on the recovery boiler is achieved. Moreover, these effects can be achieved without breaking the chemical solution recovery balance in the pulp mill.

Claims

請求の範囲 The scope of the claims 1. カッパ一価が 1 0〜 4 5のパルプを生産する蒸解法のうち、 絶乾チップに対す る液比が 1. 5〜 5. O LZk gであり、 最高温度が 1 40〜 1 80 °Cであり、 チッ プが最高温度に達するまでの時間が 5分以上である蒸解法に適用される蒸解液であつ て、 以下の標準蒸解液および液比： 3. 0 L/k g (絶乾チップ当り） で所定の条件 下で蒸解したとき、 ノ、'ルプの力ッパー価 1 8の時のパルプ収率が 50〜 5 1 %となる パルプが得られる木材チップ （学名 ： F a g u s C r e n a t a B l umeから 選ばれるチップ） を標準チップとして、 この標準チップを用い、 同一液比で同一昇温 プロファイルにおいて昇温して、 カッパ一価が 1 8のパルプを得るとき、 パルプ収率 を 3. 5 %以上上昇させ、 対チップ活性アル力リ添加率を 2 %以上低下させる蒸解液 であることを特徴とするパルプ蒸解液。 1. Among the cooking methods that produce pulp with a kappa monovalent value of 10 to 45, the liquid ratio to absolutely dry chips is 1.5 to 5. O LZkg and the maximum temperature is 140 to 180. A cooking liquor applied to a cooking process in which the maximum temperature of the chip is 5 ° C or more, and is the following standard cooking liquor and liquor ratio: 3.0 L / kg (absolute Wood chips from which pulp can be obtained when pulping under the specified conditions (under dry chips) with a pulp number of 18 and a pulp yield of 18 to 50% to 51% (scientific name: Fagus C) Using the standard chip, which is selected from renata blume, as the standard chip and using this standard chip at the same liquid ratio and the same heating profile to obtain pulp with a kappa monovalent of 18 3.It is a cooking liquor that increases by more than 5% and reduces the addition rate of chip active by more than 2%. Pulp cooking liquor. 標準蒸解液組成： Na OH 70 g/L (N a 20換算） Standard cooking liquor composition: Na OH 70 g / L ( N a 2 0 equivalent) N a2S 30 g/L (N a 20換算） N a 2 S 30 g / L (N a 20 conversion) N a 2C03 1 5 g/L (N a 20換算） N a 2 C0 3 1 5 g / L (N a 2 0 equivalent) 2. 前記蒸解液が多硫化物ィォンを含む請求の範囲 1に記載のパルプ蒸解液。 2. The pulp cooking liquor according to claim 1, wherein said cooking liquor contains polysulfide ion. 3. 前記多硫化物イオンを構成する多硫化硫黄濃度が 6 g/L以上である請求の範囲 2に記載のパルプ蒸解液。 3. The pulp cooking liquor according to claim 2, wherein the concentration of sulfur polysulfide constituting said polysulfide ion is 6 g / L or more. 4. 前記多硫化物イオンが電解法により製造される多硫化物イオンである請求の範囲 2または 3に記載のパルプ蒸解液。  4. The pulp digester according to claim 2, wherein the polysulfide ion is a polysulfide ion produced by an electrolytic method. 5. 前記パルプ蒸解液がキノン化合物を含む請求の範囲 1〜4のいずれか 1項に記載 のパルプ蒸解液。  5. The pulp cooking liquor according to any one of claims 1 to 4, wherein the pulp cooking liquor contains a quinone compound. 6. 前記パルプ蒸解液がキノン化合物を絶乾チップ当り 0. 0 1〜 1. 5重量％含有 する請求の範囲 1〜 5のいずれか 1項に記載のパルプ蒸解液。  6. The pulp cooking liquor according to any one of claims 1 to 5, wherein the pulp cooking liquor contains a quinone compound in an amount of 0.01 to 1.5% by weight per absolutely dry chip. 7. 少なくとも多硫化物イオンを含有する白液又は緑液のうち、 多硫化物イオンを構 成する多硫化硫黄濃度が 6 g / L以上で、 絶乾チップ当り 0. 0 1〜 1. 5重量％の キノン化合物を含有することを特徴とするパルプ蒸解液。  7. Of white liquor or green liquor containing at least polysulfide ions, the concentration of sulfur polysulfide constituting polysulfide ions is 6 g / L or more, and 0.01 to 1.5 per absolutely dry chip A pulp cooking liquor containing quinone compound by weight. 8. 前記パルプ蒸解液中の多硫化物ィォンが電解酸化によって製造される多硫化物ィ ォンである請求の範囲 7に記載のパルプ蒸解液。 8. Polysulfide in the pulp cooking liquor is produced by electrolytic oxidation. 8. The pulp cooking liquor according to claim 7, which is a pulp. 9 . 請求の範囲 1 〜 8のいずれか 1項に記載のパルプ蒸解液を用いることを特徴とす るパルプ製造方法。  9. A pulp production method using the pulp cooking liquor according to any one of claims 1 to 8.
PCT/JP2000/003834 1999-06-15 2000-06-13 Digesting liquor for pulp and method for producing pulp Ceased WO2000077294A1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
JP2001503731A JP4704638B2 (en) 1999-06-15 2000-06-13 Pulp cooking liquor and pulp manufacturing method
AU51097/00A AU5109700A (en) 1999-06-15 2000-06-13 Digesting liquor for pulp and method for producing pulp

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP11/169002 1999-06-15
JP16900299 1999-06-15

Publications (1)

Publication Number Publication Date
WO2000077294A1 true WO2000077294A1 (en) 2000-12-21

Family

ID=15878537

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2000/003834 Ceased WO2000077294A1 (en) 1999-06-15 2000-06-13 Digesting liquor for pulp and method for producing pulp

Country Status (3)

Country Link
JP (1) JP4704638B2 (en)
AU (1) AU5109700A (en)
WO (1) WO2000077294A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7056418B2 (en) 1999-06-15 2006-06-06 Kawasaki Kasei Chemicals Ltd. Cooking method for pulp
WO2010137535A1 (en) * 2009-05-26 2010-12-02 日本製紙株式会社 Method for digesting lignocellulosic material

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5729690A (en) * 1980-07-31 1982-02-17 Sanyo Kokusaku Pulp Co Pulping of lignocellulose material
JPH08218290A (en) * 1995-02-09 1996-08-27 Mitsubishi Paper Mills Ltd Method for producing chlorine-free bleached pulp
WO1997041295A1 (en) * 1996-04-26 1997-11-06 Asahi Glass Company Ltd. Method for producing polysulfides by electrolytic oxidation
JPH11100783A (en) * 1997-09-26 1999-04-13 Oji Paper Co Ltd Pulping method of lignocellulosic material

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA1073161A (en) * 1975-09-05 1980-03-11 Canadian Industries Limited Delignification process
JPH09268488A (en) * 1996-03-27 1997-10-14 Mitsubishi Paper Mills Ltd Kraft pulp manufacturing method
JPH10280290A (en) * 1997-03-31 1998-10-20 Mitsubishi Paper Mills Ltd Method for treating cooking waste liquid combustion melt and method for producing kraft pulp

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5729690A (en) * 1980-07-31 1982-02-17 Sanyo Kokusaku Pulp Co Pulping of lignocellulose material
JPH08218290A (en) * 1995-02-09 1996-08-27 Mitsubishi Paper Mills Ltd Method for producing chlorine-free bleached pulp
WO1997041295A1 (en) * 1996-04-26 1997-11-06 Asahi Glass Company Ltd. Method for producing polysulfides by electrolytic oxidation
JPH11100783A (en) * 1997-09-26 1999-04-13 Oji Paper Co Ltd Pulping method of lignocellulosic material

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7056418B2 (en) 1999-06-15 2006-06-06 Kawasaki Kasei Chemicals Ltd. Cooking method for pulp
WO2010137535A1 (en) * 2009-05-26 2010-12-02 日本製紙株式会社 Method for digesting lignocellulosic material
JP4629164B2 (en) * 2009-05-26 2011-02-09 日本製紙株式会社 Cooking method of lignocellulosic material

Also Published As

Publication number Publication date
JP4704638B2 (en) 2011-06-15
AU5109700A (en) 2001-01-02

Similar Documents

Publication Publication Date Title
JP4629164B2 (en) Cooking method of lignocellulosic material
JP6680395B1 (en) Method for producing bleached pulp
JP4499280B2 (en) Bleaching chemical pulp with peracids.
JP4704639B2 (en) Pulp cooking method
JPWO2000077295A1 (en) Pulp Cooking Method
JP5471049B2 (en) Method for producing TCF bleached pulp
WO2000077294A1 (en) Digesting liquor for pulp and method for producing pulp
JP4298059B2 (en) Cooking method of lignocellulosic material
JP5515409B2 (en) Method for producing ECF bleached pulp
EP1245723B1 (en) Method for recovering chemicals in a process of producing pulp by kraft process
FI68679B (en) REFERENCE TO A LABORATORY MATERIAL WITH AN ALCOHOLIC CHEMICAL MATERIAL
JP4887900B2 (en) Method for producing bleached pulp
JP5471050B2 (en) TCF bleaching method
JP4454822B2 (en) Pulp manufacturing method
JPWO2000077294A1 (en) Pulp cooking liquor and pulp manufacturing method
WO1994005851A1 (en) Novel method of bleaching of lignocellulosic pulp using persulphate
JP4298058B2 (en) Cooking method of lignocellulosic material
JPH0585677B2 (en)
JP2008150721A (en) How to use chemicals in the kraft pulp manufacturing process

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY CA CH CN CR CU CZ DE DK DM DZ EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
121 Ep: the epo has been informed by wipo that ep was designated in this application
ENP Entry into the national phase

Ref country code: JP

Ref document number: 2001 503731

Kind code of ref document: A

Format of ref document f/p: F

REG Reference to national code

Ref country code: DE

Ref legal event code: 8642

122 Ep: pct application non-entry in european phase