NO793959L - PROCEDURE FOR COLOR IMPROVEMENT AND DESODORATION OF SULPHATE CELLULOSE. - Google Patents
PROCEDURE FOR COLOR IMPROVEMENT AND DESODORATION OF SULPHATE CELLULOSE.Info
- Publication number
- NO793959L NO793959L NO793959A NO793959A NO793959L NO 793959 L NO793959 L NO 793959L NO 793959 A NO793959 A NO 793959A NO 793959 A NO793959 A NO 793959A NO 793959 L NO793959 L NO 793959L
- Authority
- NO
- Norway
- Prior art keywords
- cellulose
- sulphate
- peroxide
- kraft
- pulp
- Prior art date
Links
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 title claims abstract description 23
- 229910021653 sulphate ion Inorganic materials 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 title claims abstract description 13
- 229920002678 cellulose Polymers 0.000 title claims description 36
- 239000001913 cellulose Substances 0.000 title claims description 35
- 150000002978 peroxides Chemical class 0.000 claims abstract description 18
- 239000002655 kraft paper Substances 0.000 claims abstract description 16
- 238000009792 diffusion process Methods 0.000 claims abstract description 5
- 239000000725 suspension Substances 0.000 claims abstract description 5
- 238000002360 preparation method Methods 0.000 claims abstract description 3
- 230000001877 deodorizing effect Effects 0.000 claims abstract 2
- 238000004061 bleaching Methods 0.000 claims description 7
- 239000000463 material Substances 0.000 claims description 7
- 238000009835 boiling Methods 0.000 claims description 6
- 238000005406 washing Methods 0.000 claims description 5
- 241000294754 Macroptilium atropurpureum Species 0.000 claims description 2
- 150000002500 ions Chemical class 0.000 claims 1
- 238000010411 cooking Methods 0.000 abstract 2
- 235000010980 cellulose Nutrition 0.000 description 29
- 238000004519 manufacturing process Methods 0.000 description 10
- 238000004806 packaging method and process Methods 0.000 description 6
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 description 4
- 238000002386 leaching Methods 0.000 description 4
- 239000005022 packaging material Substances 0.000 description 4
- 239000000126 substance Substances 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 235000013305 food Nutrition 0.000 description 3
- 239000008267 milk Substances 0.000 description 3
- 210000004080 milk Anatomy 0.000 description 3
- 235000013336 milk Nutrition 0.000 description 3
- 241000196324 Embryophyta Species 0.000 description 2
- LSDPWZHWYPCBBB-UHFFFAOYSA-N Methanethiol Chemical compound SC LSDPWZHWYPCBBB-UHFFFAOYSA-N 0.000 description 2
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 238000004332 deodorization Methods 0.000 description 2
- 239000004744 fabric Substances 0.000 description 2
- 238000003860 storage Methods 0.000 description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 1
- 239000005864 Sulphur Substances 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 239000007844 bleaching agent Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 238000001035 drying Methods 0.000 description 1
- 125000001495 ethyl group Chemical group [H]C([H])([H])C([H])([H])* 0.000 description 1
- DNJIEGIFACGWOD-UHFFFAOYSA-N ethyl mercaptane Natural products CCS DNJIEGIFACGWOD-UHFFFAOYSA-N 0.000 description 1
- 235000016709 nutrition Nutrition 0.000 description 1
- 230000009965 odorless effect Effects 0.000 description 1
- 150000007524 organic acids Chemical class 0.000 description 1
- 235000005985 organic acids Nutrition 0.000 description 1
- 230000002028 premature Effects 0.000 description 1
- 230000035484 reaction time Effects 0.000 description 1
- 235000011121 sodium hydroxide Nutrition 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 239000002562 thickening agent Substances 0.000 description 1
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
- D21C9/163—Bleaching ; Apparatus therefor with per compounds with peroxides
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Wood Science & Technology (AREA)
- Paper (AREA)
- Polysaccharides And Polysaccharide Derivatives (AREA)
- Saccharide Compounds (AREA)
- Medicines Containing Material From Animals Or Micro-Organisms (AREA)
- Artificial Filaments (AREA)
Abstract
Description
Fremgangsmåte til farveforbedring og desodoreringProcedure for color improvement and deodorization
av sulfatc.ellulose.of sulphatec.ellulose.
Celluloser, som fremstilles etter kraft- og sulfatfremgangsmåten, utmerker seg ved fremragende teknologiske egenskaper. De anvendes bl.a. etter en blekning i store mengder til papirfremstilling. Celluloses, which are produced using the kraft and sulphate method, are distinguished by outstanding technological properties. They are used i.a. after bleaching in large quantities for papermaking.
I ubleket tilstand anvendes kraft- eller sulfatcellulosen i ikke ubetydelige mengder til fremstilling av emballasjemateriale som f.eks. karton. På grunn av dets meget store fasthetsegenskaper egner kraft- eller sulfat-cellulose seg spesielt for forpakninger hvor det må regnes med sterk mekanisk påkjenning. In the unbleached state, the kraft or sulphate cellulose is used in not insignificant quantities for the production of packaging material such as e.g. cardboard. Due to its very strong properties, kraft or sulphate cellulose is particularly suitable for packaging where strong mechanical stress must be expected.
Den ublekede kraft- eller sulfatcellulose har imidlertid vesentlige ulemper, !som begrenser dets anvendelse til fremstilling av pakningsmaterial uonsket•sterkt. However, the unbleached kraft or sulphate cellulose has significant disadvantages, which limit its use for the production of packaging material undesirably strongly.
Således er f. eks.1 de dannede innpakningsmaterialer på grunn av den brune farve av'cellulosen utiltalende og stygge. Videre oppstår ved sulfatkokning intens luktende svovelholdige forbindelser, som f.eks., etyl- og metylmerkaptan, som gir kraft- eller sulfatcellulosen en karakteristisk lukt som ved - vasking og torkning ikke kan fjernes med tilstrekkelig sikker-het. Spesielt uheldig virker disse egenskaper ved kraft-eller sulfatcellulosen ved næringsmiddelinnpakning, således~" at hittil var en anvendelse av ;ubleket kraft- eller sulfat-cellulose ikke mulig for dette !formål, f.eks. for melke-emballasjer. Thus, for example, the resulting packaging materials are unattractive and unsightly due to the brown color of the cellulose. Furthermore, intense-smelling sulphur-containing compounds, such as ethyl and methylmercaptan, are produced by sulphate boiling, which give the kraft or sulphate cellulose a characteristic smell which - by washing and drying - cannot be removed with sufficient certainty. These properties of the kraft or sulphate cellulose seem particularly unfortunate for food packaging, so that until now an application of unbleached kraft or sulphate cellulose was not possible for this purpose, e.g. for milk packaging.
Det bestod således et enormt behov til å lys-gjore og å desodorere på en okonomisk godtagbar måte de i . cellulosefabrikkene til disposisjon stående vanlige anlegg og således anvendeliggjore som material for fremstilling av næringsmiddelforpakninger. There was thus an enormous need to lighten and deodorize in an economically acceptable way those in . the cellulose factories have ordinary plants at their disposal and thus can be used as material for the production of food packaging.
Mens den ublekede kraft- eller sulfatcellulose fåes med et hvithetsinnhold på ca. 25 til 26, skal cellulose for næringsmiddelforpakning ha- et hvithetsinnhold fra 30 - 32 uten tap i dets gode fasthetsegenskap. While the unbleached kraft or sulphate cellulose is obtained with a whiteness content of approx. 25 to 26, cellulose for food packaging must have a whiteness content of 30 - 32 without loss in its good firmness.
For å gi forpakningsmaterial en tiltalende farve er det tilstrekkelig å forbedre hvithetsinnholdet av kraft-eller sulfatcellulose rundt ca.5 til 10 punkter. To give packaging material an appealing colour, it is sufficient to improve the whiteness content of kraft or sulphate cellulose by around 5 to 10 points.
Oppfinnelsens gjenstand er en fremgangsmåteThe object of the invention is a method
til lysgjoring og desodorering av kraft- eller sulfåt-cellulose, idet fremgangsmåten erkarakterisert vedat man etter sulfat-kokningen under stoffoppberedningen i området av en diffusjonsvask under anvendelse av. den i cellulosen for bleaching and deodorising kraft or sulphate cellulose, the method being characterized by, after the sulphate boiling, during the fabric preparation in the area of a diffusion wash using the one in the cellulose
■etter den alkaliske kokning ennu tilstedeværende restalkalitet til cellstoffsuspensjonen setter ét peroksyd i en mengde fra 0,05 til 3 vektsprosent (referert til 100%ig. peroksyd), referert til atro-cellulose. ■after the alkaline boiling, residual alkalinity still present in the cellulose suspension puts one peroxide in an amount from 0.05 to 3% by weight (referred to 100% peroxide), referred to atro-cellulose.
Derved kan det for den onskede forbedring av hvithetsgraden være nodvendig med en mengde av peroksyd fra 0,5 til 2,5 vektsprosent (100$ig peroksyd) referert til atrocellulosen, mens for desodoreringen alene kan det være tilstrekkelig med en mengde fra 0,05 til 0,3 vektsprosent peroksyd, referert til atrocellulose. Thereby, for the desired improvement in the degree of whiteness, an amount of peroxide of from 0.5 to 2.5% by weight (100% peroxide) referred to the atrocellulose may be necessary, while for the deodorization alone, an amount of from 0.05 to 0.3% by weight of peroxide, referred to atrocellulose.
Som peroksyd anvendes fortrinnsvis.hydrogen-peroksyd i vandig opplosning.<;>Cellulosesuspensjonens restalkalitet kan ved begynnelsen av tilsetningen av peroksydet tilsvare en utvaskningsgrad fra 0,2 til 1,8 vektsprosent Na^SO^, fortrinnsvis fra .1,2 til 1,5 vektsprosent Na^SO^ . Ved fremgangsmåten ifolge oppfinnelsen er det fremfor alt fordelaktig at i den benyttede ;fase av kraft- eller sulfat-cellulosefremstillingsfremgangsmåten fremkommer cellulosesuspensjonen med en stofftetthet fra 10 til 15 vektsprosent, referert til atro cellulose, ved hoye temperaturer som ligger i området fra 60 til 80°C og lagrer flere timer, fortrinnsvis 7 til 20 timer. As peroxide, hydrogen peroxide in aqueous solution is preferably used.<;>The residual alkalinity of the cellulose suspension can, at the beginning of the addition of the peroxide, correspond to a leaching degree of from 0.2 to 1.8 weight percent Na^SO^, preferably from .1.2 to 1, 5% by weight Na^SO^ . In the method according to the invention, it is above all advantageous that in the used ;phase of the kraft or sulphate cellulose manufacturing method, the cellulose suspension is produced with a material density of 10 to 15 percent by weight, referred to atro cellulose, at high temperatures that lie in the range from 60 to 80° C and stores several hours, preferably 7 to 20 hours.
Dessuten kan fremgangsmåten ifolge oppfinnelsen gjennomføres ved stofftettheter i området fra 3 til 20 vektsprosent, samt ved temperaturer i området fra 4-0 til 90°C. Moreover, the method according to the invention can be carried out at material densities in the range from 3 to 20 percent by weight, as well as at temperatures in the range from 4-0 to 90°C.
En temperatur fra 60 til 70°C er spesielt fordelaktig. A temperature of 60 to 70°C is particularly advantageous.
Cellulosens lagringstid kan dessuten utgjore mellom 1 til 25 timer og'i en fordelaktig utforelsesform 7 til 15 timer. The storage time of the cellulose can also be between 1 to 25 hours and, in an advantageous embodiment, 7 to 15 hours.
Normalt-oppnås ved produksjon av sulf at cellulose i området av diffusjonsvasking en utvaskningsgrad som er optimal for peroksydbehandlingen. Skulle dette imidlertid ikke være tilfelle så er det nodvendig å korrigere rest-alkaliteten (utvaskingsgraden). Normally, in the production of cellulose sulphate in the area of diffusion washing, a degree of leaching is achieved which is optimal for the peroxide treatment. However, should this not be the case, it is necessary to correct the residual alkalinity (leaching degree).
En for hoy alkalitet av cellulosen bevirkerA too high alkalinity of the cellulose causes
et for hurtig peroksydforbruk og dermed et-dårlig resultat.. I' et slikt tilfelle er det fordelaktig å utstyre det an-vendte peroksyd med en adekvat syremengde, som er tilstrekkelig a too rapid consumption of peroxide and thus a bad result. In such a case it is advantageous to equip the used peroxide with an adequate amount of acid, which is sufficient
•til å bringe cellulosens alkalitet til det optimale området. Som syre kan man anvende - uorganiske eller organiske syrer- •to bring the alkalinity of the cellulose to the optimum range. As an acid, you can use - inorganic or organic acids -
som ikke omfatter reduserende deler. Fortrinnsvis kan det anvendes svovelsyre. which does not include reducing parts. Preferably, sulfuric acid can be used.
Fremgangsmåten ifolge oppfinnelsen er overraskende. mulig i den omtalte fase av kraft- eller sulfat-cellulose-fremstillingsfremgangsmåten, ennskjont kjente resepturer for en celluloseblekning med peroksyd i denne fase av cellulosefremstillingen ikke gir tilstrekkelige resultater. Det består derfor den generelle herskende mening at ennu The method according to the invention is surprising. possible in the mentioned phase of the kraft or sulfate cellulose manufacturing process, although known recipes for a cellulose bleaching with peroxide in this phase of the cellulose manufacturing do not give sufficient results. It therefore remains the general prevailing opinion that still
fra kokningen tilstedeværende, |ikke utvaskede oksyderbare deler forte til eo for tidlig peroksydforbruk og umuliggjorde en blekning. 1 from the boiling present, |not washed out oxidizable parts forte to eo premature peroxide consumption and made bleaching impossible. 1
Overraskende har det nu ved fremgangsmåten ifolge oppfinnelsen vist seg at en peroksydblekning'i den omtalte fase av kraft- eller sulfat-cellulosefremstillingsfremgangs-måten er mulig, når man ser bort fra tilsetningen av den' for en- peroksydblekning fororig ubetinget nodvendige natronlut. Det kan også sees bort fra medanvendelse av kjente bleke-stabilisatorer. j Surprisingly, with the method according to the invention, it has now been shown that a peroxide bleaching in the mentioned phase of the kraft or sulphate cellulose manufacturing process is possible, when one ignores the addition of the caustic soda which was previously unconditionally necessary for peroxide bleaching. The combined use of known bleach stabilizers can also be disregarded. j
Den ved hjelp av fremgangsmåten ifolge opp- . finnelsen behandlede kraft- eller sulfat-cellulose kan uten vanskeligheter anvendes som material for næringsmidde<1>.-forpakninger, f.eks. melkepakninger. The using the procedure according to up- . kraft or sulphate cellulose treated with the invention can be used without difficulty as a material for nutritional <1> packaging, e.g. milk cartons.
Fremgangsmåten ifolge oppfinnelsen skal for-klares nærmere ved hjelp av noen eksempler. The method according to the invention will be explained in more detail with the help of some examples.
Eksempel 1Example 1
Den i en kontinuerlig koker frembragte sulfat-cellulose fores etter passering av de vanlige sorterings- The sulfate cellulose produced in a continuous boiler is fed after passing the usual sorting
og vaskeoperasjoner over siste vaskefilter, hvorpå den fremkommer med en utvaskningsgrad fra 1,2 til 1,5% Na2SO^. Stoffet inntykkes på filteret til 1$% stofftetthet, faller med 70°C i en snekke og pumpes i et tykkstofftårn, hvori det lagres 7 til 20 timer (diffusjonstårn). and washing operations over the last washing filter, after which it emerges with a leaching rate of 1.2 to 1.5% Na2SO^. The substance is thickened on the filter to 1$% substance density, falls at 70°C in a screw and is pumped into a thickener tower, in which it is stored for 7 to 20 hours (diffusion tower).
Ved tårninngangen har stoffet .26,5 hvithetsinnhold. I snekken fordeles ved hjelp av en dråperenne 1.500 l/time av en 10%ig vandig hydrogenperoksydopplosning jevnt. At the tower entrance, the fabric has a whiteness content of .26.5. 1,500 l/hour of a 10% aqueous hydrogen peroxide solution is distributed evenly in the auger using a drip chute.
Tilsvarende produksjonen av 10.000 kg/time sulfat-cellulose tilsvarer dette anvendelsen av 1,5$ HgOg. Det etter 7 timers reaksjonstid fra tårnet kontinuerlige ut-pumpede stoff har et hvithetsinnhold på 32 ved samtidig endring av farvetonen fra gråbrunt til brunlig gult. Det er praktisk talt luktlost. Fasthetsegenskapene for og etter behandlingen er like. Corresponding to the production of 10,000 kg/hour of sulphate-cellulose, this corresponds to the use of 1.5$ HgOg. After a reaction time of 7 hours from the tower, the continuously pumped out material has a whiteness content of 32 at the same time the color tone changes from grey-brown to brownish yellow. It is practically odorless. The firmness properties before and after the treatment are similar.
Eksempel 2Example 2
I det i eksempel 1 omtalte anlegg tildoseres ved samme tilsetningssted 150 l/time av en 10% ±g hydrogenperoksydopplosning, hvilket referert til stoff, tilsvarer 0,15$. Hvithetsinnholdet av det etter 10 timers reaksjons-og lagringstid fra stapeltårnet uttatte stoff var med 27,5 praktisk talt uendret. Den på forhånd intense, lukt var forsvunnet, således at stoffet kunne anvendes for en produksjon av melkekartonger. In the plant described in example 1, 150 l/hour of a 10% ± g hydrogen peroxide solution is dosed at the same point of addition, which, in terms of substance, corresponds to $0.15. The whiteness content of the material removed from the stack tower after 10 hours of reaction and storage was practically unchanged at 27.5. The previously intense smell had disappeared, so that the substance could be used for the production of milk cartons.
Claims (1)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE2905936A DE2905936B1 (en) | 1979-02-16 | 1979-02-16 | Process for lightening and deodorising sulfate pulp |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| NO793959L true NO793959L (en) | 1980-08-19 |
Family
ID=6063083
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NO793959A NO793959L (en) | 1979-02-16 | 1979-12-05 | PROCEDURE FOR COLOR IMPROVEMENT AND DESODORATION OF SULPHATE CELLULOSE. |
Country Status (6)
| Country | Link |
|---|---|
| EP (1) | EP0014753B1 (en) |
| AT (1) | ATE2019T1 (en) |
| CA (1) | CA1129157A (en) |
| DE (2) | DE2905936B1 (en) |
| FI (1) | FI68684C (en) |
| NO (1) | NO793959L (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP0073872A1 (en) * | 1981-09-03 | 1983-03-16 | Billerud Uddeholm AB | Chemical process in the manufacture of paper |
| SE442414B (en) * | 1981-09-22 | 1985-12-23 | Holmens Bruk Ab | SETTING TO REDUCE OR INHIBIT THE MARKING OF PASS OR PAPER IN BACKWATER SYSTEM |
| US4559103A (en) * | 1982-08-05 | 1985-12-17 | Honshu Seishi Kabushiki Kaisha | Packaging paper and packaging material for packaging metallic material and method of producing the same |
| RU2504375C1 (en) * | 2012-05-23 | 2014-01-20 | Галина Викторовна Сукоян | Pharmaceutical formulation for treating diseases associated with endothelial dysfunction |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US1454339A (en) * | 1921-11-28 | 1923-05-08 | Brown Co | Method of treating cellulose pulp to remove odors therefrom |
| US1632802A (en) * | 1926-08-10 | 1927-06-21 | Brown Co | Process of and apparatus for treating fiber |
| US1774403A (en) * | 1926-09-16 | 1930-08-26 | Brown Co | Process of producing fiber of high alpha cellulose content |
| US2030384A (en) * | 1934-10-18 | 1936-02-11 | Nekoosa Edwards Paper Co | Method of bleaching pulp |
| BE450336A (en) * | 1942-12-09 | 1943-05-31 | ||
| FR2192981B1 (en) * | 1972-07-21 | 1988-11-10 | Air Liquide Fr | |
| IT1071347B (en) * | 1976-03-12 | 1985-04-02 | Interox Sa | PROCESS FOR DISINFECTION OF OLD PAPER |
-
1979
- 1979-02-16 DE DE2905936A patent/DE2905936B1/en not_active Withdrawn
- 1979-11-27 FI FI793720A patent/FI68684C/en not_active IP Right Cessation
- 1979-12-04 EP EP79104899A patent/EP0014753B1/en not_active Expired
- 1979-12-04 AT AT79104899T patent/ATE2019T1/en not_active IP Right Cessation
- 1979-12-04 DE DE7979104899T patent/DE2964319D1/en not_active Expired
- 1979-12-05 NO NO793959A patent/NO793959L/en unknown
-
1980
- 1980-02-13 CA CA345,493A patent/CA1129157A/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| DE2905936B1 (en) | 1980-04-30 |
| EP0014753B1 (en) | 1982-12-15 |
| EP0014753A1 (en) | 1980-09-03 |
| CA1129157A (en) | 1982-08-10 |
| DE2964319D1 (en) | 1983-01-20 |
| ATE2019T1 (en) | 1982-12-15 |
| FI68684B (en) | 1985-06-28 |
| FI793720A (en) | 1980-08-17 |
| FI68684C (en) | 1985-10-10 |
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