NO844740L - PROCEDURE FOR PREPARING CELLULOSMASS - Google Patents
PROCEDURE FOR PREPARING CELLULOSMASSInfo
- Publication number
- NO844740L NO844740L NO844740A NO844740A NO844740L NO 844740 L NO844740 L NO 844740L NO 844740 A NO844740 A NO 844740A NO 844740 A NO844740 A NO 844740A NO 844740 L NO844740 L NO 844740L
- Authority
- NO
- Norway
- Prior art keywords
- solution
- liquid
- cooking
- boiling
- sulfur dioxide
- Prior art date
Links
- 238000000034 method Methods 0.000 title claims description 29
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 claims description 26
- 238000010411 cooking Methods 0.000 claims description 22
- 238000009835 boiling Methods 0.000 claims description 18
- 239000007788 liquid Substances 0.000 claims description 10
- 239000001913 cellulose Substances 0.000 claims description 5
- 229920002678 cellulose Polymers 0.000 claims description 5
- 238000000605 extraction Methods 0.000 claims description 5
- 238000004519 manufacturing process Methods 0.000 claims description 5
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical compound [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 claims description 5
- 239000002023 wood Substances 0.000 claims description 4
- VSGNNIFQASZAOI-UHFFFAOYSA-L calcium acetate Chemical compound [Ca+2].CC([O-])=O.CC([O-])=O VSGNNIFQASZAOI-UHFFFAOYSA-L 0.000 claims description 3
- 239000001639 calcium acetate Substances 0.000 claims description 3
- 235000011092 calcium acetate Nutrition 0.000 claims description 3
- 229960005147 calcium acetate Drugs 0.000 claims description 3
- 159000000007 calcium salts Chemical class 0.000 claims description 2
- 150000001875 compounds Chemical class 0.000 claims description 2
- ZCCIPPOKBCJFDN-UHFFFAOYSA-N calcium nitrate Chemical compound [Ca+2].[O-][N+]([O-])=O.[O-][N+]([O-])=O ZCCIPPOKBCJFDN-UHFFFAOYSA-N 0.000 claims 2
- CBOCVOKPQGJKKJ-UHFFFAOYSA-L Calcium formate Chemical compound [Ca+2].[O-]C=O.[O-]C=O CBOCVOKPQGJKKJ-UHFFFAOYSA-L 0.000 claims 1
- 229940044172 calcium formate Drugs 0.000 claims 1
- 235000019255 calcium formate Nutrition 0.000 claims 1
- 239000004281 calcium formate Substances 0.000 claims 1
- 239000002253 acid Substances 0.000 description 17
- 238000010521 absorption reaction Methods 0.000 description 7
- OYPRJOBELJOOCE-UHFFFAOYSA-N Calcium Chemical compound [Ca] OYPRJOBELJOOCE-UHFFFAOYSA-N 0.000 description 5
- 239000011575 calcium Substances 0.000 description 5
- 229910052791 calcium Inorganic materials 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- 238000010438 heat treatment Methods 0.000 description 3
- 239000012808 vapor phase Substances 0.000 description 3
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 2
- 239000003518 caustics Substances 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000002474 experimental method Methods 0.000 description 2
- 239000000203 mixture Substances 0.000 description 2
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 2
- 229910021653 sulphate ion Inorganic materials 0.000 description 2
- QGZKDVFQNNGYKY-UHFFFAOYSA-O Ammonium Chemical compound [NH4+] QGZKDVFQNNGYKY-UHFFFAOYSA-O 0.000 description 1
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 241000196324 Embryophyta Species 0.000 description 1
- DGAQECJNVWCQMB-PUAWFVPOSA-M Ilexoside XXIX Chemical compound C[C@@H]1CC[C@@]2(CC[C@@]3(C(=CC[C@H]4[C@]3(CC[C@@H]5[C@@]4(CC[C@@H](C5(C)C)OS(=O)(=O)[O-])C)C)[C@@H]2[C@]1(C)O)C)C(=O)O[C@H]6[C@@H]([C@H]([C@@H]([C@H](O6)CO)O)O)O.[Na+] DGAQECJNVWCQMB-PUAWFVPOSA-M 0.000 description 1
- 229920001732 Lignosulfonate Polymers 0.000 description 1
- 239000004117 Lignosulphonate Substances 0.000 description 1
- FYYHWMGAXLPEAU-UHFFFAOYSA-N Magnesium Chemical compound [Mg] FYYHWMGAXLPEAU-UHFFFAOYSA-N 0.000 description 1
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 1
- 235000011613 Pinus brutia Nutrition 0.000 description 1
- 241000018646 Pinus brutia Species 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- BRPQOXSCLDDYGP-UHFFFAOYSA-N calcium oxide Chemical compound [O-2].[Ca+2] BRPQOXSCLDDYGP-UHFFFAOYSA-N 0.000 description 1
- 239000000292 calcium oxide Substances 0.000 description 1
- ODINCKMPIJJUCX-UHFFFAOYSA-N calcium oxide Inorganic materials [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 description 1
- GBAOBIBJACZTNA-UHFFFAOYSA-L calcium sulfite Chemical compound [Ca+2].[O-]S([O-])=O GBAOBIBJACZTNA-UHFFFAOYSA-L 0.000 description 1
- 239000004295 calcium sulphite Substances 0.000 description 1
- 235000010261 calcium sulphite Nutrition 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000004090 dissolution Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-M hydroxide Chemical compound [OH-] XLYOFNOQVPJJNP-UHFFFAOYSA-M 0.000 description 1
- 229920005610 lignin Polymers 0.000 description 1
- 235000019357 lignosulphonate Nutrition 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 229910052749 magnesium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 235000010265 sodium sulphite Nutrition 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 238000006351 sulfination reaction Methods 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
- D21C3/00—Pulping cellulose-containing materials
- D21C3/04—Pulping cellulose-containing materials with acids, acid salts or acid anhydrides
- D21C3/06—Pulping cellulose-containing materials with acids, acid salts or acid anhydrides sulfur dioxide; sulfurous acid; bisulfites sulfites
-
- 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
Landscapes
- Paper (AREA)
- Micro-Organisms Or Cultivation Processes Thereof (AREA)
- Immobilizing And Processing Of Enzymes And Microorganisms (AREA)
Description
Foreliggende oppfinnelse vedrører en fremgangsmåte ved fremstilling av sulfitteellulose. The present invention relates to a method for the production of sulphite cellulose.
I henhold til oppfinnelsen nedsettes ved hjelp av avtrekking av kokesyre, etter at denne er absorbert av flisen, vektforholdet mellom syreoppløsningen og veden til en verdi på 2,6:1 eller til en ennå lavere verdi, hvilket inne-bærer en senkning av den opprinnelige verdi på ca. 4:1 med 35% eller mer. Etter avtrekking er det nevnte vektforhold fordelaktig 2,4:1. Ved sammenpressing av flisen kan forholdet senkes ytterligere, eksempelvis med en sammenpressing med over 10%, til en verdi under 2,2:1. According to the invention, by extracting cooking acid, after it has been absorbed by the tile, the weight ratio between the acid solution and the wood is reduced to a value of 2.6:1 or to an even lower value, which entails a lowering of the original value of approx. 4:1 with 35% or more. After subtraction, the aforementioned weight ratio is advantageously 2.4:1. When compressing the tile, the ratio can be further lowered, for example with a compression of more than 10%, to a value below 2.2:1.
I kokeren blir tilbake kun så meget oppløsning av denne kan sirkuleres gjennom en kalorisator slik at kokets temperatur kan heves eller senkes ved hjelp av den sirkuler-ende syre og det er således ikke nødvendig med en direkte tilsetning av damp, slik som er tilfelle ved den såkalte dampfasekoking. Only so much solution remains in the boiler that it can be circulated through a caloriser so that the temperature of the boiler can be raised or lowered with the help of the circulating acid and it is thus not necessary to directly add steam, as is the case with the so-called vapor phase cooking.
Fremgangsmåten ifølge oppfinnelsen kan således betegnes som en semidampfasefremgangsmåte, fordi flisen kun delvis overdekkes av oppløsningen. The method according to the invention can thus be described as a semi-vapor phase method, because the tile is only partially covered by the solution.
Fremgangsmåten ifølge oppfinnelsen forutsetter at kjemi-kalieinnholdet i kokesyren som innmates i begynnelsen av koket er så høy at etter absorpsjonstrinnet og avtrekking av kokesyre, er det tilbake i kokeren en tilstrekkelig mengde svoveldioksyd og basemengde for den egentlige koking. Dette oppnås når minst 13 g/l svoveldioksyd bindes til utgangssyrens basemengde og svoveldioksydens total-mengde er over 80 g/l, dvs. at andelen av svoveldioksyd bundet til base utgjør over 16% av den totale svoveldiok-sydmengde. Når trykket under selve kokingen holdes så høyt som mulig, dvs. at gassuttaket minimaliseres til å til-svare kokerens trykkholdfasthet så vil svoveldioksydinnholdet holde seg tilstrekkelig høyt. The method according to the invention assumes that the chemical potassium content in the cooking acid which is fed in at the beginning of the cooking is so high that after the absorption step and withdrawal of cooking acid, there is a sufficient amount of sulfur dioxide and amount of base back in the cooker for the actual cooking. This is achieved when at least 13 g/l of sulfur dioxide is bound to the base amount of the starting acid and the total amount of sulfur dioxide is over 80 g/l, i.e. that the proportion of sulfur dioxide bound to base amounts to more than 16% of the total amount of sulfur dioxide. When the pressure during the actual boiling is kept as high as possible, i.e. that the gas outlet is minimized to correspond to the boiler's pressure holding strength, the sulfur dioxide content will remain sufficiently high.
Kokesyren absorberes i flisen ved en temperatur på 80- 110°C og avtrekningen skjer innen det samme temperatur-intervall. Den egentlige koking finner sted ved en høyere temperatur enn under absorpsjons trinnet, dvs. ved 120-150°C. The cooking acid is absorbed in the tile at a temperature of 80-110°C and the extraction takes place within the same temperature interval. The actual boiling takes place at a higher temperature than during the absorption step, ie at 120-150°C.
Som base kan anvendes kjente sulfittkokebaser, eksempelvis kalsium-, ammonium-, magnesium-, eller natriumsulfitt eller blandinger derav anvendes. Ved fremgangsmåten ifølge oppfinnelsen etterstrebes i innledningstrinnet av kokingen hovedsakelig absorpsjon av kokeoppløsningen i flisen og ikke egentlig sulfinering og/eller oppløsning av ligninet, da det er ønskelig at kokesyren som erholdes ved avtrekning av denne skal inneholde kun små mengder oppløste or-ganiske bestanddeler når den tilbakeføres til kokesyre-systemet. Known sulphite boiling bases can be used as a base, for example calcium, ammonium, magnesium or sodium sulphite or mixtures thereof. In the method according to the invention, in the initial stage of cooking, the aim is mainly absorption of the cooking solution in the wood chips and not actual sulfination and/or dissolution of the lignin, as it is desirable that the cooking acid obtained by extracting this should contain only small amounts of dissolved organic components when it is returned to the cooking acid system.
Svoveldioksydinnholdet kan som kjent heves ved å tilføre kokeren konsentrert svoveldioksyd. Basemengden kan på sin side økes ved å heve innholdet av den såkalte tårnsyre ved tilsetning av det tilsvarende karbonat, hydroksyd eller oksyd. Tilførsel av base kan også skje direkte til flisen som innmates i kokeren, hvorved anvendes tilsvarende base-forbindelser. As is known, the sulfur dioxide content can be raised by adding concentrated sulfur dioxide to the boiler. The amount of base can, in turn, be increased by raising the content of the so-called tower acid by adding the corresponding carbonate, hydroxide or oxide. Supply of base can also take place directly to the chips that are fed into the boiler, whereby corresponding base compounds are used.
Et annet viktig trekk ved oppfinnelsen er for å muliggjøre en betydelig avtrekking av kokesyren mulig ved kalsium-sulfittkoking kan syrens kalsiuminnhold heves tilstrekkelig også ved tilsetning av oppløselige kalsiumsalter direkte til kokesyren. Når eksempelvis kalsiumacetat tilsettes kan kokesyrens kalsiuminnhold også derved økes til-s trekkelig. Another important feature of the invention is to enable a significant extraction of the caustic acid possible by calcium sulphite boiling, the calcium content of the acid can be raised sufficiently also by adding soluble calcium salts directly to the caustic acid. When, for example, calcium acetate is added, the calcium content of the cooking acid can also be significantly increased thereby.
Fremgangsmåtens andre fordeler er:The method's other advantages are:
kokesyrens oppvarming krever mindre energi enn tidligere, avluten for ca. 4 prosentenheter høyere konsentrasjon til inndampningsanlegget, dvs. inndampningen krever mindre energi, og The cooking acid's heating requires less energy than before, the lye for approx. 4 percentage units higher concentration for the evaporation plant, i.e. the evaporation requires less energy, and
kokingen skjer raskere, masseutbyttet er større og en lys-ere cellulose erholdes, the boiling takes place faster, the mass yield is greater and a lighter cellulose is obtained,
og and
molekylstørrelsen i avlutens lignosulfonater er større enn det som oppnås ved den vanlige fremgangsmåte. the molecular size in the effluent's lignosulphonates is larger than that obtained by the usual method.
Fra FI-patent nr. 35.726 er kjent en fremgangsmåte for fremstilling av sulfittmasse ved koking i to trinn, i det første trinn ved en temperatur på 110-130°C og i det andre trinn ved en høyere temperatur, idet ca. halve volu-met av kokevæsken trekkes av etter det første trinn, hvor-etter denne væskemengde føres til en sentral kalorisator-beholder. From FI patent no. 35,726 a method is known for the production of sulphite pulp by boiling in two stages, in the first stage at a temperature of 110-130°C and in the second stage at a higher temperature, as approx. half the volume of the cooking liquid is withdrawn after the first step, after which this amount of liquid is fed to a central caloriser container.
I henhold til foreliggende fremgangsmåte anvendes ingen sentral kalorisator fordi temperaturen under absorpsjonstrinnet kun holdes ved 80-110°C og både i det første og andre trinn skjer oppvarmingen ved at kokevæsken får sir-kulere, hvorved en mindre væskemengde er tilstrekkelig og ingen kondensering av oppvarmingsdamper i kokeren finner sted. Til tross for dette er defibreringsresultatet minst like godt som ved den kjente fremgangsmåte. According to the present method, no central calorizer is used because the temperature during the absorption step is only kept at 80-110°C and in both the first and second steps the heating takes place by allowing the cooking liquid to circulate, whereby a smaller amount of liquid is sufficient and no condensation of heating vapors in the boiler takes place. Despite this, the defibration result is at least as good as with the known method.
Fra Fl patent nr. 54.938 er kjent en fremgangsmåte ved forbedring av varmeøkonomien ved fremstilling av cellulose. På basis av påtentes utførelseseksempel kan man trekke den slutning at det dreier seg om sulfatkoking, mens foreliggende oppfinnelse vedrører sul fittkoking, dvs. de to fremgangsmåter er helt forskjellige. Dessuten utnyt-ter den kjente fremgangsmåte trykkstø teknikk for effekti-visering av absorberingen. From Fl patent no. 54,938 a method for improving the heat economy in the production of cellulose is known. On the basis of the proposed design example, it can be concluded that it concerns sulphate boiling, while the present invention relates to sulphite boiling, i.e. the two methods are completely different. In addition, the known method utilizes the pressure shock technique to make the absorption more effective.
Fra Fl patentsøknad nr. 81.2102 er kjent en annen fremgangsmåte for forbedring av varmeøkonomien ved fremstil-lingen av sulfatcellulose. På samme måte som i det ovenfor nevnte Fl patent nr. 54.938 avviker også denne fremgangsmåte seg klart fra foreliggende oppfinnelse. For å effek-tivisere absorpsjonen utføres i begynnelsen av absorpsjonstrinnet en trykkbehandling likeledes utføres slutt-trinnet som en dampfasekoking. From F1 patent application no. 81.2102 another method is known for improving the heat economy in the production of sulphate cellulose. In the same way as in the above-mentioned F1 patent no. 54,938, this method also deviates clearly from the present invention. In order to make the absorption more efficient, a pressure treatment is carried out at the beginning of the absorption step, and the final step is also carried out as a vapor phase boiling.
Fra SE patent nr. 175.684 er kjent en fremgangsmåte for koking av furuflis i to trinn under anvendelse av natrium som base (kalsium som base kan ikke anvendes når pH ligger i området 4-7). I henhold til denne fremgangsmåte fjernes kokeoppløsningen nesten helt etter det første trinnet og kondensert svoveldioksyd og/eller en vandig oppløsning av svoveldioksyd tilsettes. SE patent no. 175,684 discloses a method for boiling pine chips in two stages using sodium as a base (calcium as a base cannot be used when the pH is in the range 4-7). According to this method, the boiling solution is almost completely removed after the first step and condensed sulfur dioxide and/or an aqueous solution of sulfur dioxide is added.
EksempelExample
En rekke satskokforsøk både i laboratorie- og fabrikkskala ble utført, idet man varierte utgangssyrens sammensetning og konsentrasjon samt fremfor alt avtrekningsgraden. Ved fabrikk-kokene ble mengden av avtrukket kokesyre hevet fra det normale 25% til 35-41% og i laboratorieskala fra 20% til 40-45%. I laboratorieskala utføres også satskokforsøk idet det til kokesyren ved siden av kalsiumoksyd også ble tilsatt kalsiumacetat for å heve kalsiummengden til det betydelige nivå som avtrekkingen krever. Resultatene frem-går av tabell 1. A series of batch cooking experiments both on laboratory and factory scale were carried out, varying the composition and concentration of the starting acid and, above all, the extraction degree. At the factory boils, the amount of extracted cooking acid was raised from the normal 25% to 35-41% and on a laboratory scale from 20% to 40-45%. On a laboratory scale, batch boiling experiments are also carried out, where calcium acetate was also added to the cooking acid alongside calcium oxide to raise the amount of calcium to the significant level that the extraction requires. The results are shown in table 1.
Claims (10)
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| FI834358A FI73012C (en) | 1983-11-29 | 1983-11-29 | Process for boiling sulfite cellulose. |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| NO844740L true NO844740L (en) | 1985-05-30 |
Family
ID=8518141
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| NO844740A NO844740L (en) | 1983-11-29 | 1984-11-28 | PROCEDURE FOR PREPARING CELLULOSMASS |
Country Status (8)
| Country | Link |
|---|---|
| JP (1) | JPS60134088A (en) |
| DD (1) | DD229446A5 (en) |
| DE (1) | DE3440716A1 (en) |
| FI (1) | FI73012C (en) |
| HU (1) | HUT36873A (en) |
| NO (1) | NO844740L (en) |
| PL (1) | PL145660B1 (en) |
| SE (1) | SE8405984L (en) |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE62376C (en) * | O. SCHMIDT in Berlin N., Weifsen-I burgerstr. 48 | Process for the production of pulp | ||
| DE527950C (en) * | 1928-12-30 | 1931-06-24 | I G Farbenindustrie Akt Ges | Process for the production of sulphite pulp |
-
1983
- 1983-11-29 FI FI834358A patent/FI73012C/en not_active IP Right Cessation
-
1984
- 1984-11-07 DE DE19843440716 patent/DE3440716A1/en not_active Ceased
- 1984-11-13 HU HU421784A patent/HUT36873A/en unknown
- 1984-11-27 DD DD26993684A patent/DD229446A5/en unknown
- 1984-11-27 JP JP25036184A patent/JPS60134088A/en active Pending
- 1984-11-27 SE SE8405984A patent/SE8405984L/en not_active Application Discontinuation
- 1984-11-28 NO NO844740A patent/NO844740L/en unknown
- 1984-11-29 PL PL25063284A patent/PL145660B1/en unknown
Also Published As
| Publication number | Publication date |
|---|---|
| HUT36873A (en) | 1985-10-28 |
| SE8405984L (en) | 1985-05-30 |
| FI834358A (en) | 1985-05-30 |
| FI73012C (en) | 1987-08-10 |
| JPS60134088A (en) | 1985-07-17 |
| SE8405984D0 (en) | 1984-11-27 |
| FI834358A0 (en) | 1983-11-29 |
| DD229446A5 (en) | 1985-11-06 |
| FI73012B (en) | 1987-04-30 |
| DE3440716A1 (en) | 1985-06-05 |
| PL145660B1 (en) | 1988-10-31 |
| PL250632A1 (en) | 1985-07-16 |
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