JPH08505907A - Chlorine-free bleaching method for pulp using acetic acid as acidifying agent - Google Patents
Chlorine-free bleaching method for pulp using acetic acid as acidifying agentInfo
- Publication number
- JPH08505907A JPH08505907A JP6516930A JP51693094A JPH08505907A JP H08505907 A JPH08505907 A JP H08505907A JP 6516930 A JP6516930 A JP 6516930A JP 51693094 A JP51693094 A JP 51693094A JP H08505907 A JPH08505907 A JP H08505907A
- Authority
- JP
- Japan
- Prior art keywords
- pulp
- bleaching
- less
- acid
- peroxide
- 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.)
- Pending
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
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/16—Bleaching ; Apparatus therefor with per compounds
- D21C9/166—Bleaching ; Apparatus therefor with per compounds with peracids
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/1005—Pretreatment of the pulp, e.g. degassing the pulp
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/1026—Other features in bleaching processes
- D21C9/1042—Use of chelating agents
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
- D21C9/10—Bleaching ; Apparatus therefor
- D21C9/16—Bleaching ; Apparatus therefor with per compounds
- D21C9/163—Bleaching ; Apparatus therefor with per compounds with peroxides
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Paper (AREA)
Abstract
(57)【要約】 ケミカルパイプを製造する時に塩素を用いることなくセルロース繊維材料のパルプを漂白する方法が記載され、該方法では入来するパルプを漂白系列に連続的に供給し、pHを7以下の値に調節するために酸の存在下に金属イオン封鎖剤で処理し、その後過酸化物、少なくとも1個の有機過酸及び過酸化物よりなる一連の数段解で漂白する。本発明によると、金属イオン封鎖剤での処理ではパルプを酢酸で酸性化することが提案される。 (57) [Summary] A method is described for bleaching pulp of cellulosic fiber materials without the use of chlorine when producing chemical pipes, in which the incoming pulp is continuously fed to a bleaching series to adjust the pH to a value of 7 or less. For this purpose it is treated with a sequestering agent in the presence of an acid and then bleached with a series of several solutions consisting of a peroxide, at least one organic peracid and a peroxide. According to the invention, it is proposed to acidify the pulp with acetic acid in the treatment with the sequestrant.
Description
【発明の詳細な説明】 酸性化剤として酢酸を用いる パルプの塩素無含有漂白方法 本発明はケミカルパルプを製造する時に塩素を用いることなくセルロース繊維 材料のパルプを漂白する方法であって入来するパルプを漂白系列に連続的に供給 し、7以下のpH値に調節するために少なくとも1種の酸の存在下に金属イオン 封鎖剤で処理し、その後に過酸化物、1種又はそれ以上の有機過酸及び過酸化物 よりなる一連の数段解で漂白する、パルプの漂白方法に関する。 パルプを漂白するのに塩素含有漂白剤の使用に関して環境上の要件が厳しくな ったことにより、塩素化有機化合物を形成する塩素含有漂白剤が不利である一方 で、環境に悪影響を及ぼさない別の漂白剤を見出すのに広範囲の調査研究がなさ れた。即ち例えばスウェーデン特許公開(SE−A)9101300−3号に記載される 方法の如く金属イオン封鎖剤での処理に続いてオゾン及び過酸化物を種々の順序 で用いてパルプを漂白することが提案された。然しながらオゾンを用いると多数 の欠点を生ずる。オゾンはセルロースに分解作用を及ぼし、漂白過程に関連して オゾンを製造し且つ供給する装置は大規模で高価である。スウェーデン特許(SE −B)405130号に対応する米国特許公開(US−A)3,867,246号は塩素を用いる ことなく過酸化物、過酢酸及び過酸化物の工程順序を含めて別の漂白方法を記載 しており、第1の過酸化物段階に先 立って低いpH値に調節するために酸の存在下に金属イオン封鎖剤での処理を行 なう。用いる酸は一般に硫酸である。然しながら、オゾンと同様に過酢酸もまた セルロースに強い分解作用を及ぼす。 本発明の目的は、酸の存在下に金属イオン封鎖剤(Q)での処理に続いて漂白 処理工程PPaPにおいて過酸化物と組合せて過酢酸を用いて、塩素を用いることな くパルプを漂白する際の欠点を解決するものであり、こうして満足な粘度と強度 特性と市場で要求される85〜90%ISO(国際標準規格)の白色度とを有する即 座に漂白したパルプが得られる。 本発明の方法は金属イオン封鎖剤での処理中にパルプを酢酸で酸性化すること を特徴としている。 原料パルプは低いカッパー価を与える蒸煮法により製造するのが好ましく、そ の後に酸素ガスで脱リグニン化を行ってパルプが約12又はそれ以下のカッパー価 と少なくとも約1000dm3/kgの粘度とを有する程度まで脱リグニン化する。 用いた過酸化物は過酸化水素であるのが好ましい。 第1の過酸化物段階に続いて第2の漂白段階は過ギ酸、過酢酸又は過プロピオ ン酸、好ましくは過酢酸又は前記過酸の少なくとも2種の混合物を用いて行なう 。 適当な具体例によると、酢酸はpH値が6以下、好ましくは5以下であるよう な量で添加する。 全ての漂白段階中の温度は80℃又はそれ以上であり好 ましくは90℃である。 各々の過酸化物段階はアルカリ溶液中で行なうのが適当である。 過酢酸段階は酸性溶液中で行なうのが好ましい。 酢酸及び過酢酸又は他の適当な過酸はその場で製造するのが好ましい。 種々の処理段階中のパルプの稠度(コンシステンシー)は約8〜16%、好まし くは9〜11%である。 次の実施例は本発明を更に説明し且つその予期せぬ結果を示す。実施例 酸素ガスで脱リグニン化されしかも洗浄された針葉樹材の硫酸塩パルプを用い て多数の実験を実施した。脱リグニン化したパルプは12.1のカッパー価と33.7% のISO白色度と1020dm3/kgの粘度とを有した。このパルプを10%の稠度で漂 白系列中に供給し、この稠度を金属イオン封鎖剤EDTAでの処理中及び全ての 漂白段階中は維持した。実験1及2では硫酸をQ−段階における酸性化剤として 用い、然るに本発明による実験3及び4では酢酸を酸性化剤として用いた。 実験1−4 結果が示す処によれば、驚くべきことには本発明により予備処理し且つ漂白し たパルプは実験1及び2により予備処理し且つ漂白したパルプと比較すると有意 な程に向上した粘度を有し、そしてまた向上した強度特性を示している。第2の 漂白段階で当量の過酢酸(Pa)即ち実験1及び3では20kg、実験2及び4では30 kgを用い、Q−段階では酸性化剤として硫酸の代りに酢酸を用いるとそれぞれ26 単位及び50単位だけ粘度が増大した。 前述した如く、酢酸及び過酢酸又は他の適当な過酸は その場で製造するのが好ましい。例えば、酢酸はパルプを製造する時にパルプの 1トン当り50kgまでの量で黒液から回収できる。例えば過酢酸は回収した酢酸か ら既知の要領で製造できる。従って本発明の方法は経済的な見地からきわめて有 利な要領で実施できる。DETAILED DESCRIPTION OF THE INVENTION Chlorine-free bleaching method for pulp using acetic acid as acidifying agent The present invention is a method for bleaching pulp of cellulosic fiber material without using chlorine when producing chemical pulp. The pulp is continuously fed to the bleaching series and treated with a sequestering agent in the presence of at least one acid to adjust the pH value below 7, followed by peroxide, one or more The present invention relates to a method for bleaching pulp, which is bleached with a series of multistage solutions consisting of an organic peracid and a peroxide. Due to the stringent environmental requirements for the use of chlorine-containing bleaching agents to bleach pulp, chlorine-containing bleaching agents that form chlorinated organic compounds are disadvantageous while other environmentally harmful substances are not adversely affected. Extensive research has been done in finding bleach. It is therefore proposed to bleach the pulp using ozone and peroxide in various orders following treatment with a sequestrant, for example as described in Swedish patent publication (SE-A) 9101300-3. Was done. However, the use of ozone causes a number of drawbacks. Ozone has a degradative effect on cellulose and the equipment for producing and supplying ozone in connection with the bleaching process is large and expensive. U.S. Pat. No. 3,867,246, corresponding to Swedish patent (SE-B) 405130, describes an alternative bleaching method including the process sequence of peroxide, peracetic acid and peroxide without the use of chlorine. Prior to the first peroxide step, a treatment with a sequestrant in the presence of acid is carried out in order to adjust the pH value to a low value. The acid used is generally sulfuric acid. However, like acetic acid, peracetic acid also has a strong degrading effect on cellulose. The object of the present invention is to bleach pulp without chlorine using peracetic acid in combination with peroxide in the bleaching process PPaP following treatment with a sequestrant (Q) in the presence of acid. It solves the drawbacks of the prior art and thus gives an instant bleached pulp with satisfactory viscosity and strength properties and a market demand of 85-90% ISO (International Standard) brightness. The process of the invention is characterized by acidifying the pulp with acetic acid during treatment with the sequestrant. The raw pulp is preferably produced by a steaming process that gives a low Kappa number, followed by delignification with oxygen gas so that the pulp has a Kappa number of about 12 or less and a viscosity of at least about 1000 dm 3 / kg. Delignify to some extent. The peroxide used is preferably hydrogen peroxide. Following the first peroxide stage, a second bleaching stage is carried out with performic acid, peracetic acid or perpropionic acid, preferably peracetic acid or a mixture of at least two of said peracids. According to a suitable embodiment, acetic acid is added in an amount such that the pH value is below 6, preferably below 5. The temperature during all bleaching stages is 80 ° C or higher, preferably 90 ° C. Suitably each peroxide step is carried out in an alkaline solution. The peracetic acid step is preferably carried out in acidic solution. Acetic acid and peracetic acid or other suitable peracids are preferably prepared in situ. The consistency of the pulp during the various treatment steps is about 8-16%, preferably 9-11%. The following example further illustrates the present invention and shows its unexpected results. EXAMPLE A number of experiments were carried out with softwood sulphate pulp which had been delignified with oxygen gas and washed. The delignified pulp had a Kappa number of 12.1, an ISO whiteness of 33.7% and a viscosity of 1020 dm 3 / kg. The pulp was fed into the bleaching series at a consistency of 10% and was maintained during the treatment with the sequestering agent EDTA and during all bleaching stages. In experiments 1 and 2 sulfuric acid was used as the acidifying agent in the Q-stage, while in experiments 3 and 4 according to the invention acetic acid was used as the acidifying agent. Experiment 1-4 The results show that, surprisingly, the pulp pretreated and bleached according to the invention has a significantly improved viscosity compared to the pretreated and bleached pulp according to Experiments 1 and 2, It also shows improved strength properties. In the second bleaching stage, an equivalent amount of peracetic acid (Pa), ie 20 kg in experiments 1 and 3 and 30 kg in experiments 2 and 4, was used in the Q-stage and 26 units each were obtained by using acetic acid instead of sulfuric acid as the acidifying agent. And the viscosity increased by 50 units. As mentioned above, acetic acid and peracetic acid or other suitable peracids are preferably prepared in situ. For example, acetic acid can be recovered from black liquor when producing pulp in an amount of up to 50 kg per tonne of pulp. For example, peracetic acid can be produced from recovered acetic acid in a known manner. Therefore, the method of the invention can be carried out in a very advantageous manner from an economical point of view.
───────────────────────────────────────────────────── フロントページの続き (81)指定国 EP(AT,BE,CH,DE, DK,ES,FR,GB,GR,IE,IT,LU,M C,NL,PT,SE),OA(BF,BJ,CF,CG ,CI,CM,GA,GN,ML,MR,NE,SN, TD,TG),AT,AU,BB,BG,BR,BY, CA,CH,CN,CZ,DE,DK,ES,FI,G B,HU,JP,KP,KR,KZ,LK,LU,LV ,MG,MN,MW,NL,NO,NZ,PL,PT, RO,RU,SD,SE,SK,UA,US,UZ,V N, , ─────────────────────────────────────────────────── ─── Continued front page (81) Designated countries EP (AT, BE, CH, DE, DK, ES, FR, GB, GR, IE, IT, LU, M C, NL, PT, SE), OA (BF, BJ, CF, CG , CI, CM, GA, GN, ML, MR, NE, SN, TD, TG), AT, AU, BB, BG, BR, BY, CA, CH, CN, CZ, DE, DK, ES, FI, G B, HU, JP, KP, KR, KZ, LK, LU, LV , MG, MN, MW, NL, NO, NZ, PL, PT, RO, RU, SD, SE, SK, UA, US, UZ, V N ,,
Claims (1)
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE9300277-2 | 1993-01-29 | ||
SE9300277A SE501325E (en) | 1993-01-29 | 1993-01-29 | Process for chlorine-free bleaching of pulp, wherein the pulp is acidified with acetic acid in the treatment with complexing agents |
PCT/SE1994/000054 WO1994017239A1 (en) | 1993-01-29 | 1994-01-26 | Method for chlorine-free bleaching of pulp with acetic acid as acidifying agent |
Publications (1)
Publication Number | Publication Date |
---|---|
JPH08505907A true JPH08505907A (en) | 1996-06-25 |
Family
ID=20388704
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP6516930A Pending JPH08505907A (en) | 1993-01-29 | 1994-01-26 | Chlorine-free bleaching method for pulp using acetic acid as acidifying agent |
Country Status (10)
Country | Link |
---|---|
EP (1) | EP0681624A1 (en) |
JP (1) | JPH08505907A (en) |
CN (1) | CN1117301A (en) |
AU (1) | AU675291B2 (en) |
BR (1) | BR9406193A (en) |
CA (1) | CA2154076A1 (en) |
FI (1) | FI111387B (en) |
NO (1) | NO305763B1 (en) |
SE (1) | SE501325E (en) |
WO (1) | WO1994017239A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103726382A (en) * | 2013-12-31 | 2014-04-16 | 安徽泾县千年古宣宣纸有限公司 | Pure straw Chinese art paper and chloride-free bleaching production process thereof |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN1050642C (en) * | 1996-06-25 | 2000-03-22 | 华南理工大学 | Everyday production 30-150 ton high concentration paper pulp bleaching method by using hydrogen peroxide |
EP3882380B1 (en) * | 2020-03-16 | 2022-04-27 | Re:NewCell AB | One stage method for acid metal removal and bleach |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2219505C3 (en) * | 1972-04-21 | 1974-10-17 | Deutsche Gold- Und Silber-Scheideanstalt Vormals Roessler, 6000 Frankfurt | Chlorine-free multi-stage bleaching of cellulose |
DE2841013C2 (en) * | 1978-09-21 | 1984-06-07 | Degussa Ag, 6000 Frankfurt | Process for full bleaching of pulp |
ATE97179T1 (en) * | 1989-06-06 | 1993-11-15 | Eka Nobel Ab | PROCESS FOR BLEACHING LIGNOCELLULOSE CONTAINING PULP. |
SE468355B (en) * | 1991-04-30 | 1992-12-21 | Eka Nobel Ab | CHEMISTRY OF CHEMICAL MASS THROUGH TREATMENT WITH COMPLEX PICTURES AND OZONE |
-
1993
- 1993-01-29 SE SE9300277A patent/SE501325E/en not_active IP Right Cessation
-
1994
- 1994-01-26 CA CA 2154076 patent/CA2154076A1/en not_active Abandoned
- 1994-01-26 JP JP6516930A patent/JPH08505907A/en active Pending
- 1994-01-26 CN CN 94191058 patent/CN1117301A/en active Pending
- 1994-01-26 AU AU59820/94A patent/AU675291B2/en not_active Expired - Fee Related
- 1994-01-26 EP EP94905899A patent/EP0681624A1/en not_active Ceased
- 1994-01-26 BR BR9406193A patent/BR9406193A/en not_active IP Right Cessation
- 1994-01-26 WO PCT/SE1994/000054 patent/WO1994017239A1/en active IP Right Grant
-
1995
- 1995-07-24 NO NO952935A patent/NO305763B1/en not_active IP Right Cessation
- 1995-07-27 FI FI953589A patent/FI111387B/en active
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN103726382A (en) * | 2013-12-31 | 2014-04-16 | 安徽泾县千年古宣宣纸有限公司 | Pure straw Chinese art paper and chloride-free bleaching production process thereof |
Also Published As
Publication number | Publication date |
---|---|
CN1117301A (en) | 1996-02-21 |
SE501325E (en) | 1999-09-20 |
NO952935L (en) | 1995-09-13 |
FI953589A (en) | 1995-07-27 |
FI953589A0 (en) | 1995-07-27 |
CA2154076A1 (en) | 1994-08-04 |
SE9300277L (en) | 1994-07-30 |
NO952935D0 (en) | 1995-07-24 |
WO1994017239A1 (en) | 1994-08-04 |
NO305763B1 (en) | 1999-07-19 |
SE9300277D0 (en) | 1993-01-29 |
EP0681624A1 (en) | 1995-11-15 |
SE501325C2 (en) | 1995-01-16 |
AU5982094A (en) | 1994-08-15 |
BR9406193A (en) | 1996-01-09 |
AU675291B2 (en) | 1997-01-30 |
FI111387B (en) | 2003-07-15 |
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