FI88316C - Process for bleaching cellulose pulp - Google Patents
Process for bleaching cellulose pulp Download PDFInfo
- Publication number
- FI88316C FI88316C FI893338A FI893338A FI88316C FI 88316 C FI88316 C FI 88316C FI 893338 A FI893338 A FI 893338A FI 893338 A FI893338 A FI 893338A FI 88316 C FI88316 C FI 88316C
- Authority
- FI
- Finland
- Prior art keywords
- pulp
- bleaching
- chlorine
- oxidation
- enzyme
- Prior art date
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Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21C—PRODUCTION OF CELLULOSE BY REMOVING NON-CELLULOSE SUBSTANCES FROM CELLULOSE-CONTAINING MATERIALS; REGENERATION OF PULPING LIQUORS; APPARATUS THEREFOR
- 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
- D21C9/1057—Multistage, with compounds cited in more than one sub-group D21C9/10, D21C9/12, D21C9/16
-
- 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
- D21C5/00—Other processes for obtaining cellulose, e.g. cooking cotton linters ; Processes characterised by the choice of cellulose-containing starting materials
- D21C5/005—Treatment of cellulose-containing material with microorganisms or enzymes
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- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Biochemistry (AREA)
- Microbiology (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Paper (AREA)
- Noodles (AREA)
- Hard Magnetic Materials (AREA)
- Agricultural Chemicals And Associated Chemicals (AREA)
- Investigating Or Analysing Biological Materials (AREA)
- Silver Salt Photography Or Processing Solution Therefor (AREA)
- Cereal-Derived Products (AREA)
- Table Devices Or Equipment (AREA)
Abstract
Description
8831 68831 6
MENETELMÄ SELLULOOSAMASSAN VALKAISEMISEKSIMETHOD FOR BLEACHING CELLULOSE PULP
Tämän keksinnön kohteena on menetelmä selluloosamassan valkai-semiseksi, jossa menetelmässä käytetään hapettavaa klooripi-toista valkaisukemikaa1ia.The present invention relates to a process for bleaching cellulose pulp using an oxidizing chlorine-containing bleaching chemical.
Varsinkin sulfaattikeitolla saatu selluloosamassa on väriltään ruskeaa, mikä johtuu pääasiassa massassa jäljellä olevasta ligniinistä. Ligniiniä poistetaan valkaisulla, joka on yleensä useampivaiheinen prosessi, jossa massaa käsitellään vuorotellen hapettavilla, ligniiniä hajottavilla kemikaaleilla ja hajoamistuloksena syntyviä aineita liuottavilla kemikaaleilla. Eniten käytettyjä hapetuskemikaaleja ovat olleet klooripitoi-set aineet sekä happi, kun taas hajoamistuotteita poistavina kemikaaleina on käytetty aikaii1iuoksia.In particular, the cellulose pulp obtained by sulphate soup is brown in color, mainly due to the lignin remaining in the pulp. Lignin is removed by bleaching, which is usually a multi-stage process in which the pulp is treated alternately with oxidizing, lignin-degrading chemicals and dissolving chemicals. The most widely used oxidizing chemicals have been chlorine-containing substances and oxygen, while time solutions have been used as decomposition chemicals.
Klooria sisältävät valkaisukemikaalit muuttavat reagoidessaan massan sisältämää ligniiniä orgaanisiksi klooriyhdisteiksi, jotka joutuvat massasta poistuvaan valkaisujäteveteen. Valkai-sujätevedet ovat ympäristönsuojelulle ongelma veteen joutuvien orgaanisten klooriyhdisteiden mahdollisen myrkyllisyyden vuoksi, ja myös kemiallisen hapenkulutuksen arvot va 1 kaisujäte -vesissä ovat haitallisen korkeat.Chlorine-containing bleaching chemicals react to convert the lignin in the pulp to organic chlorine compounds, which end up in the bleaching effluent leaving the pulp. Bleaching effluents are a problem for environmental protection due to the potential toxicity of organochlorine compounds entering the water, and the values of chemical oxygen demand in effluent wastes are also harmfully high.
Ympäristöä pahimmin kuormittavat va 1 kaisujätevedet syntyvät valkaisun ensimmäistä kloorausta ja ensimmäistä aika 1ivaihetta seuraavissa pesuvaiheissa. Kuormitusta on pyritty alentamaan eri menetelmillä, kuten korvaamalla kloorikaasua klooridioksi-dilla tai käyttämällä happea ensimmäisen valkaisuvaiheen hapettavana kemikaalina, tai valkaisujäteveden biologisella puhdistuksella. Kuitenkaan näillä keinoin ei ole päästy täysin tyydyttäviin tuloksiin. Klooridioksidin käytöllä ja happivalkaisulla on tosin onnistuttu tuntuvastikin vähentämään kloorifenolien ja muiden myrkyllisten klooriyhdisteiden määrää jätevedessä, mutta veden kemiallisen hapenkulutuksen arvoja ei ole - saatu alenemaan riittävästi. Näin ollen mainittujen menetelmi- - en tueksi on tarvittu tehokas biologinen puhdistus.The effluents from the bleaching, which have the greatest impact on the environment, are generated in the washing steps following the first chlorination and the first time of bleaching. Efforts have been made to reduce the load by various methods, such as replacing chlorine gas with chlorine dioxide or using oxygen as the oxidizing chemical in the first bleaching stage, or by biological treatment of the bleaching effluent. However, these measures have not yielded completely satisfactory results. Although the use of chlorine dioxide and oxygen bleaching have significantly reduced the amount of chlorophenols and other toxic chlorine compounds in wastewater, the values of chemical oxygen demand in water have not been reduced sufficiently. Thus, effective biological purification is needed to support said methods.
2 38316 Tämän keksinnön tarkoituksena on muodostaa ratkaisu, jolla selluloosamassa on valkaistavissa siten, että valkaisujäteve-den myrkyllisyys vähenee ja samalla veden kemiallisen hapenkulutuksen arvo alenee niin, että veden puhdistustarve jää pienemmäksi. Tunnusomaista keksinnölle on se, että massalle suoritetaan hapetuksen yhteydessä tai ennen sitä entsyymikäsitte-ly, jossa käytetään ligniiniä modifioivaa hapetus-pelkistys-entsyymiä.The object of the present invention is to provide a solution by which cellulose pulp can be bleached in such a way that the toxicity of the bleaching effluent is reduced and at the same time the value of the chemical oxygen demand of the water is reduced so that the need for water purification is reduced. The invention is characterized in that the pulp is subjected to an enzyme treatment using a lignin-modifying oxidation-reduction enzyme during or before the oxidation.
Aikaisemmissa tutkimuksissa on havaittu, että hemise11uloosaa hajoittavien entsyymien avulla on mahdollista irroittaa ligniiniä ja/tai hemise1luloosaa selluloosasta ja tehdä massa tällä tavoin helpommin vaalenevaksi seuraavissa valkaisuvai-heissa. Ligniiniä modifioivia entsyymejä käytettäessä ei ole tähän mennessä pystytty osoittamaan samanlaista vaikutusta.Previous studies have found that hemisululose-degrading enzymes make it possible to release lignin and / or hemisululose from cellulose and thus make the pulp more easily bleached in subsequent bleaching steps. To date, no similar effect has been shown with lignin-modifying enzymes.
Keksinnön mukaan on nyt havaittu, että sopivalla hapetus-pelkisty sen tsyym i 1 lä suoritettu käsittely pienentää valkaisuun tarvittavien kloorikemikaalien määrää ja siten myös valkaisu-jäteveden orgaanisia klooriyhdisteitä.According to the invention, it has now been found that treatment with a suitable oxidation-reducing enzyme reduces the amount of chlorine chemicals required for bleaching and thus also the organochlorine compounds in the bleaching effluent.
Keksinnön mukaan entsymaattisen reaktion redox-potentiaali on mielellään alle 400 mV, sopivimmin alle 250 mV. Sopivia hape-tus-pe 1 kistysentsyymejä ovat mm. feno 1ioksidaasit, joista esimerkkinä voidaan mainita valkolahottajasienen tuottama laktaa-s i .According to the invention, the redox potential of the enzymatic reaction is preferably less than 400 mV, more preferably less than 250 mV. Suitable oxidation enzymes include e.g. phenol oxidases, exemplified by the lactate produced by the white rot fungus.
E ntsyymikäsi11e lyä lukuunottamatta keksinnön mukainen massan valkaisu voi tapahtua tavanomaiseen tapaan siten, että hapetus- ja a 1kaa1ivaiheet vuoro11e 1 evat ja kunkin mainitun vaiheen jälkeen massa pestään va1 kaisukemikaa1ien ja pilkkoutuneiden aineosien poistamiseksi.With the exception of the enzyme process, the bleaching of the pulp according to the invention can take place in a conventional manner in such a way that the oxidation and scale steps take place and after each step the pulp is washed to remove bleaching chemicals and degraded constituents.
E ntsyymikäsi11e ly tapahtuu keksinnön mukaan edullisesti lämpötila-alueella 10-90 C, sopivimmin alueella 40-80 C, ja pH:ssa 3,0-10,0, sopivimmin 4,0-8,0. Käytetty entsyymi on ligniiniä modifioiva hapetus-pelkistysentsyymi, esim. edellämainittu lakkaasi .According to the invention, the enzyme treatment preferably takes place in the temperature range from 10 to 90 ° C, preferably in the range from 40 to 80 ° C, and at a pH of 3.0 to 10.0, most preferably 4.0 to 8.0. The enzyme used is a lignin-modifying oxidation-reduction enzyme, e.g. the above-mentioned laccase.
3 ό 8 6 '1 63 ό 8 6 '1 6
Keksinnön kohteena on myös ligniiniä modifioivan hapetus-pel-kistysentsyymin, kuten esim. valkolahottajasienen tuottaman lakkaasin käyttö selluloosan valkaisussa, jossa käytetään hapettavaa klooripitoista valkaisukemikaalia.The invention also relates to the use of a lignin-modifying oxidation-reduction enzyme, such as, for example, laccase produced by white rot fungi, in the bleaching of cellulose using an oxidizing chlorine-containing bleaching chemical.
Keksintöä selostetaan seuraavassa lähemmin laboratoriokokeisiin perustuvien suoritusesimerkkien avulla.The invention is described in more detail below by means of exemplary embodiments based on laboratory experiments.
Es imerkki 1 220 g:an mäntysulfaattikeitosta saatua massakuiva-ainetta (massan kuiva-ainepitoisuus 30 %) lisättiin laimennettua ent-syymiseosta, Trametes hirsuta -valkolahottajasienen lakkaasia, siten, että seoksen sakeudeksi tuli 10 % ja lakkaasiaktiivisuudeksi 60 U/kg massan kuiva-ainetta. Entsyymikäsittelyn lämpötila oli 55 °C ja käsittelyaika 2 h. Entsyymikäsittelyn jälkeen sulppu suodatettiin Buchner-suppilossa ja saatua massa-kakkua pestiin ionivaihdetulla vedellä siten, että pesusuh-teeksi tuli 20.Example 1 To 220 g of pulp sulphate soup dry matter (pulp dry matter content 30%) was added a diluted enzyme mixture, Trametes hirsuta white rot fungus laccase, so that the mixture had a consistency of 10% and a laccase activity of 60 U / kg dry matter. . The temperature of the enzyme treatment was 55 ° C and the treatment time was 2 h. After the enzyme treatment, the stock was filtered in a Buchner funnel and the resulting mass cake was washed with deionized water to a washing ratio of 20.
Vertailua varten käsiteltiin vastaava massasulppuerää samalla tavalla mutta ilman entsyymi1isäystä.For comparison, the corresponding batch of pulp was treated in the same way but without the addition of enzyme.
Seuraavaksi suoritettiin entsyymikäsitellylle massasulppueräl-le ja vertailuerälle valkaisu, joka tapahtui viidessä peräkkäisessä hapetus- ja uuttovaiheessa. Ensimmäisessä vaiheessa kemikaaleina käytettiin klooria (90%) ja klooridioksidia (10%), toisessa vaiheessa natriumhydroksidia, kolmannessa vaiheessa klooridioksidia, neljännessä vaiheessa natriumhydroksidia ja viidennessä vaiheessa klooridioksidia.Next, the enzyme-treated pulp stock and the control batch were subjected to bleaching in five successive oxidation and extraction steps. Chlorine (90%) and chlorine dioxide (10%) were used as chemicals in the first stage, sodium hydroxide in the second stage, chlorine dioxide in the third stage, sodium hydroxide in the fourth stage and chlorine dioxide in the fifth stage.
Va 1 kaisukemikaa1ien kulutukset ja valkaistun massan laatua kuvaavat analyysitulokset on esitetty taulukossa 1.The consumption of bleaching chemicals and the analytical results describing the quality of the bleached pulp are shown in Table 1.
Koe osoittaa, että kloorin määrää on oleellisesti pystytty vähentämään valkaisussa käyttämällä ligniiniä modifioivaa entsyymiä, lakkaäsia, hyväksi.The experiment shows that the amount of chlorine in bleaching has been substantially reduced by using a lignin-modifying enzyme, lacquer glove.
*8316 4 TAULUKKO 1* 8316 4 TABLE 1
Entsyymikäsittely, loppu pH visk kappa saanto% mäntysulfaatiimassa, kappa 27.4 vertailuerä 8.70 1020 26.4 100.84 entsyymikäsiteltymassa 8.60 1045 26.5 100.63Enzyme treatment, end pH viscous kappa yield% pine sulphate pulp, kappa 27.4 reference batch 8.70 1020 26.4 100.84 enzyme treatment pulp 8.60 1045 26.5 100.63
Koesarja jatkuu valkaisuekvenssillä D/C-E-D-E-DThe test series continues with the bleaching sequence D / C-E-D-E-D
D/C 10/90 vertailu- entsyymi- - vaihe erä käsitelty D/C 2* kappa massa D/C annos % 5.28 5.30 kulutus % 5.28 5.30 pH 1.65 1.55 sakeus % 3.5 3.5 lämpötila °C 55 55 aikamin. 45 45 E-vaihe E 0.9*kappa E-annos % 2.38 2.39 pH 11.65 11.3 kappa 9.6 8.2 saanto % 96.13 96.81 D-vai he annos % 3.0 3.0 kulutus % 3.0 3.0 pH 1.9 1.8 sakeus % 10 10 lämpötila °C 70 70 aika min. 180 180 E2-vaihe : annos X 1.0 1.0 pH 11.2 11.3 sakeus Ϊ 10 10 lämpötila °C 60 60 aikamin. 90 90 D2-vaihe annos Ϊ 1.5 1.5 kulutus % 1.5 1.42 pH 2.2 2.2 sakeus % 10 10 lämpötila °C 75 75 aikamin. 240 240 hapotus pH 4.2 3 saanto % 97.96 98.18 kok.saanto % 94.96 95.65 vaaleus 83.8 87.1 viskositeetti TC1 mg/kg 3^45 265 DKM-uute %D / C 10/90 Reference enzyme - step batch treated D / C 2 * kappa pulp D / C dose% 5.28 5.30 consumption% 5.28 5.30 pH 1.65 1.55 consistency% 3.5 3.5 temperature ° C 55 55 time. 45 45 E-phase E 0.9 * kappa E-dose% 2.38 2.39 pH 11.65 11.3 kappa 9.6 8.2 yield% 96.13 96.81 D-or they dose% 3.0 3.0 consumption% 3.0 3.0 pH 1.9 1.8 consistency% 10 10 temperature ° C 70 70 time min. 180 180 E2 step: dose X 1.0 1.0 pH 11.2 11.3 consistency Ϊ 10 10 temperature ° C 60 60 for a while. 90 90 D2 phase dose Ϊ 1.5 1.5 consumption% 1.5 1.42 pH 2.2 2.2 consistency% 10 10 temperature ° C 75 75 time. 240 240 acidification pH 4.2 3 yield% 97.96 98.18 total yield% 94.96 95.65 brightness 83.8 87.1 viscosity TC1 mg / kg 3 ^ 45 265 DCM extract%
Claims (7)
Priority Applications (8)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FI893338A FI88316C (en) | 1989-07-10 | 1989-07-10 | Process for bleaching cellulose pulp |
AT89117234T ATE100157T1 (en) | 1989-07-10 | 1989-09-18 | METHOD OF BLEACHING SULFATE PULP. |
NO893715A NO175105C (en) | 1989-07-10 | 1989-09-18 | Method of Bleaching Mass |
DE89117234T DE68912322D1 (en) | 1989-07-10 | 1989-09-18 | Process for bleaching sulfate pulp. |
EP89117234A EP0408803B1 (en) | 1989-07-10 | 1989-09-18 | Procedure for the bleaching of sulphate pulp |
CA000611772A CA1335184C (en) | 1989-07-10 | 1989-09-18 | Procedure for the bleaching of pulp involving the use of laccase, a lignin-modifying oxidation-reduction enzyme |
JP1241665A JP2831048B2 (en) | 1989-07-10 | 1989-09-18 | Pulp bleaching method |
ES89117234T ES2061857T3 (en) | 1989-07-10 | 1989-09-18 | PROCEDURE FOR THE BLEACHING OF PAPER PASTA. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FI893338A FI88316C (en) | 1989-07-10 | 1989-07-10 | Process for bleaching cellulose pulp |
FI893338 | 1989-07-10 |
Publications (4)
Publication Number | Publication Date |
---|---|
FI893338A0 FI893338A0 (en) | 1989-07-10 |
FI893338A FI893338A (en) | 1991-01-11 |
FI88316B FI88316B (en) | 1993-01-15 |
FI88316C true FI88316C (en) | 1993-04-26 |
Family
ID=8528744
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
FI893338A FI88316C (en) | 1989-07-10 | 1989-07-10 | Process for bleaching cellulose pulp |
Country Status (8)
Country | Link |
---|---|
EP (1) | EP0408803B1 (en) |
JP (1) | JP2831048B2 (en) |
AT (1) | ATE100157T1 (en) |
CA (1) | CA1335184C (en) |
DE (1) | DE68912322D1 (en) |
ES (1) | ES2061857T3 (en) |
FI (1) | FI88316C (en) |
NO (1) | NO175105C (en) |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FI108800B (en) * | 1991-05-07 | 2002-03-28 | Iogen Corp | A method and apparatus for using an enzyme in the manufacture and bleaching of pulp |
US5498534A (en) * | 1992-03-25 | 1996-03-12 | The United States Of America As Represented By The Secretary Of Agriculture | Method of removing color from wood pulp using xylanase from streptomyces roseiscleroticus NRRL B-11019 |
US5369024A (en) * | 1992-03-25 | 1994-11-29 | The United States Of America As Represented By The Secretary Of Agriculture | Xylanase from streptomyces roseiscleroticus NRRL-11019 for removing color from kraft wood pulps |
CA2115881C (en) * | 1993-02-25 | 2000-05-23 | Michael G. Paice | Non-chlorine bleaching of kraft pulp |
US5480801A (en) * | 1993-09-17 | 1996-01-02 | Novo Nordisk A/S | Purified PH neutral Rhizoctonia laccases and nucleic acids encoding same |
US6824646B2 (en) | 1999-03-23 | 2004-11-30 | Oji Paper Co., Ltd. | Process for oxygen bleaching and enzyme treating lignocellulosic pulp with liquid treatment and recovery |
US6942754B2 (en) | 1999-03-23 | 2005-09-13 | Oji Paper Co., Ltd. | Process for producing xylooligosaccharide from lignocellulose pulp |
FI113879B (en) | 2000-05-23 | 2004-06-30 | Valtion Teknillinen | A new coating enzyme |
ES2221529B1 (en) * | 2002-07-10 | 2005-11-01 | Instituto Nacional De Investigacion Y Tecnologia Agraria Y Alimentaria (Inia) | PROCEDURE FOR THE DESLIGNIFICATION OF CELLULOSE PASTA. |
CN109537343A (en) * | 2018-11-29 | 2019-03-29 | 崔雪柯 | A kind of paper pulp gas-water separation technique |
Family Cites Families (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE3636208A1 (en) * | 1986-10-24 | 1988-05-05 | Call Hans Peter | METHOD FOR DELIGNIFYING AND WHICH BLEACHING LIGNICELLULOSE-CONTAINING OR LIGNINAL MATERIAL OR LIGNIN BY ENZYMATIC TREATMENT |
-
1989
- 1989-07-10 FI FI893338A patent/FI88316C/en active IP Right Grant
- 1989-09-18 DE DE89117234T patent/DE68912322D1/en not_active Expired - Lifetime
- 1989-09-18 NO NO893715A patent/NO175105C/en not_active IP Right Cessation
- 1989-09-18 ES ES89117234T patent/ES2061857T3/en not_active Expired - Lifetime
- 1989-09-18 AT AT89117234T patent/ATE100157T1/en not_active IP Right Cessation
- 1989-09-18 EP EP89117234A patent/EP0408803B1/en not_active Expired - Lifetime
- 1989-09-18 JP JP1241665A patent/JP2831048B2/en not_active Expired - Lifetime
- 1989-09-18 CA CA000611772A patent/CA1335184C/en not_active Expired - Fee Related
Also Published As
Publication number | Publication date |
---|---|
ES2061857T3 (en) | 1994-12-16 |
FI893338A0 (en) | 1989-07-10 |
EP0408803B1 (en) | 1994-01-12 |
NO893715L (en) | 1991-01-11 |
DE68912322D1 (en) | 1994-02-24 |
NO175105C (en) | 1994-08-31 |
NO893715D0 (en) | 1989-09-18 |
JPH03130485A (en) | 1991-06-04 |
JP2831048B2 (en) | 1998-12-02 |
FI893338A (en) | 1991-01-11 |
EP0408803A1 (en) | 1991-01-23 |
NO175105B (en) | 1994-05-24 |
ATE100157T1 (en) | 1994-01-15 |
CA1335184C (en) | 1995-04-11 |
FI88316B (en) | 1993-01-15 |
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