EP0413736A1 - Method of making mechanical and chemi-mechanical papermaking pulp. - Google Patents
Method of making mechanical and chemi-mechanical papermaking pulp.Info
- Publication number
- EP0413736A1 EP0413736A1 EP19890905472 EP89905472A EP0413736A1 EP 0413736 A1 EP0413736 A1 EP 0413736A1 EP 19890905472 EP19890905472 EP 19890905472 EP 89905472 A EP89905472 A EP 89905472A EP 0413736 A1 EP0413736 A1 EP 0413736A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- pulp
- ton
- kwh
- beating
- mechanical
- 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.)
- Granted
Links
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 18
- 239000000463 material Substances 0.000 claims abstract description 31
- 238000000034 method Methods 0.000 claims abstract description 25
- 239000002253 acid Substances 0.000 claims abstract description 5
- 238000010009 beating Methods 0.000 claims description 25
- 239000002023 wood Substances 0.000 claims description 22
- 229920005610 lignin Polymers 0.000 claims description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 229920000642 polymer Polymers 0.000 claims description 5
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 4
- 229920001131 Pulp (paper) Polymers 0.000 abstract description 19
- 238000007670 refining Methods 0.000 abstract description 10
- 238000005265 energy consumption Methods 0.000 description 30
- GEHJYWRUCIMESM-UHFFFAOYSA-L sodium sulfite Chemical compound [Na+].[Na+].[O-]S([O-])=O GEHJYWRUCIMESM-UHFFFAOYSA-L 0.000 description 10
- 239000000126 substance Substances 0.000 description 9
- 239000000835 fiber Substances 0.000 description 8
- 150000002500 ions Chemical class 0.000 description 7
- 230000000875 corresponding effect Effects 0.000 description 6
- 235000010265 sodium sulphite Nutrition 0.000 description 5
- 241000218657 Picea Species 0.000 description 4
- 238000000149 argon plasma sintering Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 4
- LSNNMFCWUKXFEE-UHFFFAOYSA-L sulfite Chemical compound [O-]S([O-])=O LSNNMFCWUKXFEE-UHFFFAOYSA-L 0.000 description 4
- BDHFUVZGWQCTTF-UHFFFAOYSA-N sulfonic acid Chemical group OS(=O)=O BDHFUVZGWQCTTF-UHFFFAOYSA-N 0.000 description 4
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 238000005470 impregnation Methods 0.000 description 3
- 239000000725 suspension Substances 0.000 description 3
- 241000905957 Channa melasoma Species 0.000 description 2
- NINIDFKCEFEMDL-UHFFFAOYSA-N Sulfur Chemical compound [S] NINIDFKCEFEMDL-UHFFFAOYSA-N 0.000 description 2
- 239000005864 Sulphur Substances 0.000 description 2
- 238000010790 dilution Methods 0.000 description 2
- 239000012895 dilution Substances 0.000 description 2
- 238000011835 investigation Methods 0.000 description 2
- 150000002978 peroxides Chemical class 0.000 description 2
- 239000000243 solution Substances 0.000 description 2
- 238000005406 washing Methods 0.000 description 2
- NLZUEZXRPGMBCV-UHFFFAOYSA-N Butylhydroxytoluene Chemical compound CC1=CC(C(C)(C)C)=C(O)C(C(C)(C)C)=C1 NLZUEZXRPGMBCV-UHFFFAOYSA-N 0.000 description 1
- MYMOFIZGZYHOMD-UHFFFAOYSA-N Dioxygen Chemical compound O=O MYMOFIZGZYHOMD-UHFFFAOYSA-N 0.000 description 1
- 101100234002 Drosophila melanogaster Shal gene Proteins 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
- 241000489861 Maximus Species 0.000 description 1
- 235000015076 Shorea robusta Nutrition 0.000 description 1
- 244000166071 Shorea robusta Species 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- LSNNMFCWUKXFEE-UHFFFAOYSA-N Sulfurous acid Chemical class OS(O)=O LSNNMFCWUKXFEE-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 125000003178 carboxy group Chemical group [H]OC(*)=O 0.000 description 1
- 125000002843 carboxylic acid group Chemical group 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 230000006835 compression Effects 0.000 description 1
- 238000007906 compression Methods 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 229910001882 dioxygen Inorganic materials 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- ZZUFCTLCJUWOSV-UHFFFAOYSA-N furosemide Chemical compound C1=C(Cl)C(S(=O)(=O)N)=CC(C(O)=O)=C1NCC1=CC=CO1 ZZUFCTLCJUWOSV-UHFFFAOYSA-N 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 239000012071 phase Substances 0.000 description 1
- 238000003825 pressing Methods 0.000 description 1
- 229910052708 sodium Inorganic materials 0.000 description 1
- 239000011734 sodium Substances 0.000 description 1
- 238000006277 sulfonation reaction Methods 0.000 description 1
- 229910021653 sulphate ion Inorganic materials 0.000 description 1
- 230000008961 swelling Effects 0.000 description 1
Classifications
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21B—FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT
- D21B1/00—Fibrous raw materials or their mechanical treatment
- D21B1/04—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres
- D21B1/12—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres by wet methods, by the use of steam
-
- D—TEXTILES; PAPER
- D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
- D21B—FIBROUS RAW MATERIALS OR THEIR MECHANICAL TREATMENT
- D21B1/00—Fibrous raw materials or their mechanical treatment
- D21B1/04—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres
- D21B1/12—Fibrous raw materials or their mechanical treatment by dividing raw materials into small particles, e.g. fibres by wet methods, by the use of steam
- D21B1/14—Disintegrating in mills
- D21B1/16—Disintegrating in mills in the presence of chemical agents
Definitions
- This invention relates to a method of making mechanical and chemi-mechanical papermaking pulp by disintegrating and beating wood material in at least two steps.
- One object of the invention is to carry out the disinte ⁇ gration and beating in such a manner, that the total energy consumption is substantially reduced, as will be be described in the following.
- the beating of cellulose-containing material at low pulp concentration is a method, which has been employed since long in order to improve the paperforming propert ⁇ ies of the fibres. This applies, however, only to fibres free of lignin or substantially free of lignin, such as fibres produced according to the sulphate or sulphite method.
- pulps manufactured mechanically such as thermomechanical pulp (TMP) or chemi-mechanical pulp (CTMP)
- beating at low concentration so-called post- -refining, was not considered applicable other than as a method for increasing the light-scattering capacity of the pulps and for reducing slightly the fibre length and thereby improving the formation at the making of paper.
- thermomechanical pulp with fibre-modifying chemicals Experiments have been carried out previously to treat thermomechanical pulp with fibre-modifying chemicals. It was then found, that by treating the defibered pulp with ozone prior to the refining in a two-step process the en consumption could be lowered by up to 30%. This, however could be achieved only at the expense of the yield.
- the wood material in a first step is coarse-disintegrated at a concentration of above 20%.
- the energy input here shal be at maximum 800 kWh/ton wood material.
- the acid groups included in the wood material thereafter shall be neutra ized entirely or partially, and the material be diluted with water of a temperature corresponding to the softeni temperature of the lignin.
- the dilution water shall have ion strength of at maximum 0.05 mole per litre.
- the coars -disintegrated material then shall be beaten at a concen ⁇ tration of 1-10% with an energy input of totally a maximu of 500 kWh/ton material.
- the present invention is based on the idea that there is a relation between the disintegration of the wood materia to fibres and the way, in which the energy pulses are transferred to the material, i.e. whether the energy puls are transferred in liquid phase or steam phase. Attention also is to be paid to the thermal and physical state of the wood material when the energy pulses are being trans ⁇ ferred.
- the energy input in the first coarse-defibering step must be low.
- the first high concentration step can be at atmospheric pressure or pressurized and be carried out by tearing (shredding), chip pressing, plug screwing (type Impressa- finer or PREX) or by defibering in a refiner.
- the final beating then takes place in one or several step at low pulp concentration, i.e. at a concentration of 1-10%.
- the temperature at the beating shall be at least as high as the softening temperature of the stiffest amorphous wood polymer, that the acid groups of the wood polymers substantially are ionized, and that the ion strength of the process water is sufficiently low.
- FIG. 1 is a flow sheet of an embodiment of the method according to the invention
- Figs. 2—4 are diagrams of properties and energy consump ion of a pulp manufactured according to Fig. 1
- Fig. 5 is a flow sheet of a second embodiment of the invention.
- Figs. 6- ⁇ show properties and energy consumption at the method according to said second embodiment.
- the flow sheet according to Fig. 1 illustrates the manu acture of thermomechanical pulp for newsprint.
- Chips from spruce were steamed in a first step and preh ed.
- the preheated chips then were disintegrated in a pressurized refiner with an energy consumption of 700 kWh/ton.
- 3 kg NaOh were added in the beating zone of the refiner for neutralizing aci groups included in the wood material.
- To the defibered material dilution water with a temperature of 80 C and ion strength of 2.0 mmole/1 was added in order to' obtai a pulp concentration of 3%.
- the pulp then was beaten in five subsequent steps at a specific edge load of 0.3-0.5 ws/ and a total net energy consumption of 150 kWh/ton pulp corresponding to a gross energy consumption of 250 kWh/ ton pulp to a freeness of 150 ml CSF and a mean fibre length (PML) of 1.8 mm, i.e. about equal to TMP-pulp manufactured in conventional manner with an energy con ⁇ sumption of 1750 kWh/ton pulp.
- PML mean fibre length
- the total energy consumption at the method according to the invention thus, was reduced from 1750 to 950 kWh/ ton pulp.
- TMP mean particle length measured according to SIFI pulp measuring system
- the manufacture of TMP according to the invention is com pared in Fig. 2, 3 and 4 with TMP manufactured conventio ally with single-step refining in twin-disc refiner, whi is the least energy consuming TMP-process existing with the present state of art.
- Fig. 2 shows the tensile index as a function of the elec energy consumption. It appears clearly from the Figure, the increase in tensile inde at a certain electric ene consumption is considerably greater for TMP manufacture according to the invention.
- Fig. 3 shows the tear index as a function of the tensil index for TMP according to the invention and convention TMP. It appears that the development of the tear index for the respective TMP is about the same, i.e. at optim ation of the low concentration beating according to the invention the fibre cutting and thereby the serious de ⁇ crease in tear index are substantially entirely avoided which cutting and decrease occur usually at conventiona low concentration beating of mechanical pulps.
- Fig. 4 shows how the light-scattering coefficient (s) develops at conventional TMP and TMP manufactured accor ing to the invention. It appears that the s-development requires as low an electric energy input as the tensile index development, i.e. the saving of electric energy t a certain s-value is of equal size as the saving of el ⁇ ectric energy to a certain tensile index value.
- This example relates to the manufacture of chemi-mechan al pulp (CTMP or CMP) according to the flow sheet shown in Fig. 5.
- CMP chemi-mechan al pulp
- impregnation chemicals which can be sulphites, peroxide, oxygen gas, ozone and/or liquor, can take place prior to the first defibering step, after this step but prior to the final beating, after the fina beating, or at combinations of these. In the flow sheet shown the impregnation is carried out prior to the first defibering step.
- the first defibering step at high concentration is carri out in the same way as in Example 1.
- washing is very essential, so that according to the invention th beating shall take place at low ion strength. The washin therefore, is carried out prior to the final beating. In cases when the chemical treatment is carried out as the last process step, washing takes place even after this step.
- the final beating takes place in the same way as accordi to Example 1, but process temperature and chemical envir ment must be adjusted to the special properties, which t wood polymers have assumed by treatment with impregnatio chemicals. It is essential to pay regard to the number of sulphonic acid groups, which have been introduced by possible sulphite treatment. As an increasing amount of sulphonic acid groups reduces the softening temperature of the lignin, the temperature of the process water can be lower than at the manufacture of TMP-pulp according to Example 1. A sufficiently high temperature at the manufacture of CTMP is 4 ⁇ °C. From a brightness point of view it is advantageous to use the lowest possible temp ⁇ erature. By sodium sulphite treatment both the sulphonic acid groups and the carboxylic acid groups ate ionized from the beginning.
- the pulp then was beaten with a specific edge load of 0.3-0.5 Ws/m in five subsequent steps with a net energy consumption of 150 kWh/ton correspond ing to a gross energy consumption of 250 kWh/ton for obtaining a pulp with a freeness of 250 ml CSF and a mean fibre length (PML) of 1.7 mm, i.e. as a convention ally manufactured CTMP-pulp produced in one step with an energy consumption of 1750 kWh/ton.
- PML mean fibre length
- the en ⁇ ergy consumption was reduced from the conventional 1750 kWh/ton to 850 kWh/ton.
- Fig. 6 the tensile index is shown as a function of the energy consumption for a CTMP-pulp manufactured accor ing to the invention and for pulp manufactured convention ally. Compared at a certain tensile index, for example 40 kNm/kg, conventional refining consumes about 1750 kWh/ ton pulp while at the method according to the invention only about 850 kWh/ton are consumed.
- the light-scattering coefficient of the CTMP-pulp manuf ⁇ actured according to the invention as a function of the energy consumption is shown in the diagram in Fig. 8 compared with conventionally manufactured pulp. It shows here that according to the invention the energy consumpt ⁇ ion to a certain light-scattering index is substantially lower.
- This example relates to the manufacture of highly sulfon- ated CTMP or CMP, i.e pulp containing more than 4 g of bound sulphur per kg wood material.
- Chips from spruce were impregnated with a sodium sulphite solution containing about 120 g of sodium sulphite per litre in an amount corresponding to a charge of about 12%.
- the chips were preheated at a temperature of 140 C for 10 minutes, whereafter they were coarse-disintegrate with an energy consumption of about 400 kWh/ton wood.
- the defibration was carried out in a pressurized chip refiner, and the yield obtained was 93-94%.
- This embodiment is an example of how in the first step extruders can be used for coarse-disintegrating wood material. According to the example an extruder of the type Bivis was used.
- Spruce chips were steamed in the usual manner at 100 C for 10 minutes, whereafter they were fed into a Bivis- machine. At the defibration in the machine 2-3% sodium sulphite solution was charged so that the sulfonation degree of the material amounted to 1.5 g of sulphur per kg wood. The electric energy consumtion was about 400 kWh/ton wood when the material passed through the four compression zones of the twin-rscrew. After discharge, the fibre material was diluted to about 5% pulp concen ⁇ tration at about 70°C, whereafter the suspension was pumped to beating in seven steps in a low concentration refiner. After the fifth beating step, the freeness of the pulp was about 250 ml CSF, the tensile index was
- the total energy consumption for the manufacture of chemi-mechanical pulp (CTMP) to a freeness value of 250 ml CSF by the method according to the invention thus, amounts to 650 kWh/ton, which is to be compared with about 1750 kWh/ton according to the best conventi ⁇ onal technique for obtaining the same freeness value.
- CTMP chemi-mechanical pulp
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Wood Science & Technology (AREA)
- Mechanical Engineering (AREA)
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Paper (AREA)
Abstract
L'invention concerne un procédé de fabrication mécanique et chimiomécanique de pâte à papier avec une entrée à faible énergie par désintégration et raffinage en pile de matériau ligneux dans au moins deux étapes. Selon l'invention, le matériau subit une désintégration grossière dans une première étape à une concentration dépassant 20 %, on neutralise les groupes d'acide se trouvant dans le matériau ligneux, puis on dilue ledit matériau jusqu'à obtention d'une concentration de 1 à 10 % et on le raffine dans une ou plusieurs étapes.The invention relates to a process for the mechanical and chemomechanical manufacture of paper pulp with a low energy input by disintegration and refining in a pile of woody material in at least two steps. According to the invention, the material undergoes a coarse disintegration in a first step at a concentration exceeding 20%, the acid groups found in the woody material are neutralized, then said material is diluted until a concentration of 1 to 10% and it is refined in one or more stages.
Description
Claims
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT89905472T ATE94596T1 (en) | 1988-05-06 | 1989-04-05 | PROCESS FOR PRODUCTION OF MECHANICAL OR CHEMICAL-MECHANICAL PAPER PULP. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE8801731 | 1988-05-06 | ||
SE8801731A SE461103B (en) | 1988-05-06 | 1988-05-06 | PREPARATION OF MECHANICAL AND CHEMICAL MECHANICS IN TWO STEPS |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0413736A1 true EP0413736A1 (en) | 1991-02-27 |
EP0413736B1 EP0413736B1 (en) | 1993-09-15 |
Family
ID=20372264
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP19890905472 Expired - Lifetime EP0413736B1 (en) | 1988-05-06 | 1989-04-05 | Method of making mechanical and chemi-mechanical papermaking pulp |
Country Status (7)
Country | Link |
---|---|
EP (1) | EP0413736B1 (en) |
JP (1) | JPH03504256A (en) |
CA (1) | CA1320067C (en) |
DE (1) | DE68909231T2 (en) |
FI (1) | FI91787C (en) |
SE (1) | SE461103B (en) |
WO (1) | WO1989010998A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5853534A (en) * | 1992-12-30 | 1998-12-29 | Sunds Defibrator Industries Ab | Method of producing pulp with high yield using a two-stage refining system operating at different temperatures |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE9002039D0 (en) * | 1990-06-07 | 1990-06-07 | Svenska Traeforskningsinst | SAVE TO PREPARE |
US6899791B2 (en) | 1997-08-08 | 2005-05-31 | Andritz Inc. | Method of pretreating lignocellulose fiber-containing material in a pulp refining process |
US8734611B2 (en) * | 2008-03-12 | 2014-05-27 | Andritz Inc. | Medium consistency refining method of pulp and system |
SE540961C2 (en) * | 2016-05-23 | 2019-01-29 | Holmen Ab | Method of providing a paper fibre composition by combining chemical and mechanical pulping |
Family Cites Families (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
SE409476B (en) * | 1978-02-17 | 1979-08-20 | Sca Development Ab | KIT FOR REFINING LIGNOCELLULOSE-MATERIAL |
JPS564791A (en) * | 1979-06-18 | 1981-01-19 | Kogyo Gijutsuin | Bleaching of mechanical pulp |
CA1246374A (en) * | 1983-10-24 | 1988-12-13 | Steve Rowland | Two stage high consistency refiner |
SE456826B (en) * | 1986-04-18 | 1988-11-07 | Svenska Traeforskningsinst | SET TO REDUCE ENERGY CONSUMPTION BY REFINING CELLULOSALLY MATERIAL |
-
1988
- 1988-05-06 SE SE8801731A patent/SE461103B/en not_active IP Right Cessation
-
1989
- 1989-04-05 JP JP50517689A patent/JPH03504256A/en active Pending
- 1989-04-05 WO PCT/SE1989/000172 patent/WO1989010998A1/en active IP Right Grant
- 1989-04-05 EP EP19890905472 patent/EP0413736B1/en not_active Expired - Lifetime
- 1989-04-05 DE DE89905472T patent/DE68909231T2/en not_active Expired - Fee Related
- 1989-05-02 CA CA000598482A patent/CA1320067C/en not_active Expired - Fee Related
-
1990
- 1990-11-05 FI FI905482A patent/FI91787C/en not_active IP Right Cessation
Non-Patent Citations (1)
Title |
---|
See references of WO8910998A1 * |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5853534A (en) * | 1992-12-30 | 1998-12-29 | Sunds Defibrator Industries Ab | Method of producing pulp with high yield using a two-stage refining system operating at different temperatures |
Also Published As
Publication number | Publication date |
---|---|
WO1989010998A1 (en) | 1989-11-16 |
DE68909231T2 (en) | 1994-04-28 |
EP0413736B1 (en) | 1993-09-15 |
CA1320067C (en) | 1993-07-13 |
SE8801731L (en) | 1989-11-07 |
FI91787C (en) | 1994-08-10 |
FI91787B (en) | 1994-04-29 |
SE8801731D0 (en) | 1988-05-06 |
DE68909231D1 (en) | 1993-10-21 |
SE461103B (en) | 1990-01-08 |
FI905482A0 (en) | 1990-11-05 |
JPH03504256A (en) | 1991-09-19 |
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