US2582054A - Pulping process - Google Patents

Pulping process Download PDF

Info

Publication number
US2582054A
US2582054A US696603A US69660346A US2582054A US 2582054 A US2582054 A US 2582054A US 696603 A US696603 A US 696603A US 69660346 A US69660346 A US 69660346A US 2582054 A US2582054 A US 2582054A
Authority
US
United States
Prior art keywords
liquor
digester
temperature
digesting
cooking
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.)
Expired - Lifetime
Application number
US696603A
Other languages
English (en)
Inventor
Michon Jacques Bernard Marie
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Cellulose du Pin SA
Original Assignee
Cellulose du Pin SA
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Cellulose du Pin SA filed Critical Cellulose du Pin SA
Application granted granted Critical
Publication of US2582054A publication Critical patent/US2582054A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • D21C7/00—Digesters
    • D21C7/06—Feeding devices

Definitions

  • This invention relates to the making of cell losic pulp by alkaline, processes.
  • the raw materials that are useful in the making of suchpulps are many, including straw, esparto, bamboo, rushes, bagasse and corn stalks, papyrus, asparagus, pea and bean vines, grasses, andparticularly wood.
  • wood is the most important of pulp sources
  • the invention will be-described in particular relation to the pulping of wood chips, but it is to be understood that this particular description is not a limitation, the process being applicable to the other raw materials with changes in conditions of treatment adapted to their particular state.
  • the process will be described in particular relation to the soda and sulfate processes which are alkaline processes in commercial use in many parts of the world, but it is to be understood that the process is equally applicable with other alkaline cooking liquors.
  • Another object of the invention is to reduce the time required to pulp celiulosic material such as chips and, by producing a superior pulp, to reduce the time required for refining it.
  • Another object 01' the invention is to make pulp continuously and of high quality by moving a stream of chips along a path and operating upon them to perform the pulping during their progress.
  • Another object of the invention is to recover the liquor used for lignin removal and to employ it repeatedly.
  • Another object of the invention is to remove the lignin separately from the hemi-celluloses oi woody material.
  • Yet another object of the invention is to construct novel apparatus adapted to handle cellulosic raw material in accordance with the process of the invention.
  • the hemi-celluloses are dissolved in the same step that dissolves the lignin. and first, because the hemi-celluloses dissolve at a lower temperature in a cooking liquor 01' selected concentration. It is a part of this invention to retain hemi-celluloses 'in the pulp by raising the temperature of the cooking liquor and of the chips, to the temperature at which lignin dissolves. so
  • the chips are impregnated with hot digesting liquor not under pressure prior to the digesting step.
  • the chips are first impregnated with the cooking liquor, then drownedin a lake of the cooking liquor under pressure at a temperature above that at which hemi-celluloses dissolve, and then cooked in that quantity of liquor which is retained after the liquid is drained oil.
  • Fig. 1 is a vertical sectional view diagrammatically illustrating an apparatus embodying principles of the invention and adapted to carry out the novel process;
  • Fig. 2 is an enlarged detail of a portion of Fig. 1;
  • the size of the stand pipe is so related to the rate of withdrawal from below that the chips are well impregnated with the liquor before they are sealed off in the digester.
  • the liquid supply system is related to all the parts of the apparatus and will be described as a unit in' connection therewith after the'mechanical parts of the apparatus have been completely described.
  • the stand pipe opens into a cylindrical or tubular digester l2 which is open at both ends, except for sealing means, and which is provided with apertures l3, l4 in the bottom of its wall. It has an external flange at one end which serves to mount a packing gland that seals the joint between it and the inner tube IS.
  • a rod 40 is diagrammatically shown as a means for moving the slidpanel, the rod passing through the end of .the'well which isprovidedat that point with a stufilng box. The motion of the panel may be secured by hand or by machine.
  • into which the contents of the digester are pushed from time to time, the previous digester charges being sealing means which are provided and which will be described hereinafter in connection with the fluid system.
  • a hollow piston 30 attached to the piston rod IS.
  • the hollow piston is sealed within the tube by piston rings 31 and has a foraminous pressure wall 32, and a valved wall 33.
  • a valved wall 33 In the valved wall are a plurality of valves 34 adapted to seal the piston when seated in conical seats 35. normally spring biased to closed position. However, the presence of liquid within the inner tube l6 under sufiicient pressure will serve to open them.
  • Fig. 1 the apparatus is shown in the first position before digestion has begun and after the stand pipe has been filled with chips.
  • the impregnating liquid has been admitted and has made it way down through the stand pipe so that the chips within the digester are submergedin the hot liquid.
  • the valves 34 are closed so that the liquid cannot escape through the piston.
  • valve 36 of sliding panel type which is shown in the illustration to be mounted for vertical sliding movement in a well 31, 38.
  • the sliding panel is solid at its lower portion, but is provided with an opening 39 in its upper part.
  • the solid portion of the panel is of The valves 34 are.
  • the cooking material is advanced step-wise until at the upper end of the tower it is elected through a steam separator 42,- the steam escaping upward and the pulp being discharged downward to a beating engine or other selected parts of the refining system.
  • the raw cellulosic material is inserted in the stand pipe until it is filled, and thereafter as required to keep an adequate supply and to provide for satisfactory impregnation.
  • the inner tube 16 is withdrawn to the position shown in Fig. 1, and the sliding panel 36 is elevated to the position shown'in Fig. 1.
  • the raw material therefore fills the stand pipe and the portion of the digester between the piston and the panel.
  • the impregnating liquid is poured by' the means shown in the drawing or by other means.
  • the rate of progress of the raw material through the stand pipe is so related to the flow of impregnatingliquid that satisfactory impregnation is secured before the chips are sealed in the digester.
  • the digester having been filled with impregnated raw material, the inner tube It is forced into engagement with the ring 23, sealing oil the digester from the impregnator.
  • the digester is now completely sealedand hotter liquid under pressure can be admitted throughthe valve ll and retained in the digester for a period sufficient to complete that stage of the operation.
  • the liquid is drained off the raw material, the valve 36 is lowered'into the well portion 31, and the piston forces the solid contents'of the digester, together with the absorbed liquid. through the opening 39 into the tower 4!, after which the panel is returned to its sealing position and the piston and inner tube are retracted to admit another charge of impregnated raw material.
  • is maintained at the most satisfactory temperature by whatever heating meansare desired.
  • One digesting-liquid is preferably employed in all the steps of the process although digesting liquor of different concentration or of different constitution could be employed if any advantage were obtained thereby.
  • the digesting liquors employed are preferably of alkali type such as soda or sulfate digesting liquors.
  • a satisfactory lconeentration is 70 grams of active alkali (NaOH or NaOH+-Na2S) per litre.
  • This liquid is contained in a reservoir 50 which is diagrammaticallyindicated in Fig. 1.
  • the reservoir is connected by a pipe line ii in which is a pump ting the wall thereof so as not to form a barrier to the passage of raw materials. Wetting of the materials toward the center of the stand pipe is cared for by suitably; directing some of the spray orifices.
  • the liquor makes its may downward through the raw materials into the digester and the lower part of the stand pipe, in which is located a means for controlling the level of the liquid.
  • this comprises a ring 54 sealed in liquid-tight fashion to the outside of the stand pipe and connected to itsinterior through holes 55 in the wall thereof.
  • a pipe 56 connects the ring with the reservoir so that any excess of liquor beyond that required to fill the digester and the stand pipe to the level of the ring is drawn off and returned to the reservoir.
  • the ring 23 is connected with the reservoir 50 by "means of a pipe 51, 58 in which is located a valve versing the flow of liquid through the stand pipe,
  • the reservoir 50 is also connected to the digester by means of a pipe line 6
  • the pressure in the system at this point will be equal to that which is generated by the pump 62 at the temperature furnished by the reheater 65.
  • the digesting liquor remains liquid at temperatures above its normal boiling point.
  • the temperature and pressures under which this liquid is maintained are materially higher than those at which the hemi-celluloses dissolve.
  • the capacity of the system is such that materially large quantities of liquid may be mixed with the cellulosic raw material suddenly.
  • the celthe pipe 69 will drain from the valve chamber 68 through the valve 61L to the reservoir 50 through the pipe line 10.
  • valves 59 and 61R can be automatically regulated toavoid the formation of any air pockets within the" digester.
  • means may be provided, operable through the center 6f the piston rod to unseat the valves 34 and permit the escape of liquids through pipe 6-9 and valve 61L, valve 51R being simultaneously unclosed.
  • the piston 30 is now thrust against the digested cellulosic material and compresses it in a compact mass as shown in Fig. 4, simultaneously squeezing out of it substantially all superfluous liquor. Under normal conditions, this amount will roughly equal the weight of the cellulosic material. It is my discovery that this amount of liquor is suflicient to produce an excellent pulp and that material advantages of efficiency and economy are attained by the removal of excess liquors as accomplished by this process and apparatus.
  • the gate 36 is now opened and the charge in the digester is expelled'by the piston into the cooking tower 4
  • the first impregnation, in tower Ill may be at such concentration, temperature, and time as will produce a dissolution of any fraction of hemi-celluloses desired, or to'avoid dissolving any hemi-celluloses.
  • the temperature of the alkali liquor during impregnation in tower [0 may approach 0. without dissolving the hemicelluloses, the concentration of alkali may be about 70 grams per liter, and impregnation may continue for about a half hour.
  • the impregnating liquor is drained off, a charge is sealed off from the mass undergoing impregnation, and about four times the weight of the chips of hot alkali liquor at a temperature at which lignin dissolves and above that at which hemicellulose dissolves namely circa I'm-180 C., is suddenly made to drown the drained chips.
  • This raises the temperature'of the wood so suddenly to the high temperature at which lignin dissolves that the hemicelluloses are aifected little or none.
  • the total temperature rise occurs in about five minutes or less, which does not give the liquor time to dissolve the hemicelluloses.
  • the chip mass is in a sealed chamber or digester during the drowning with the C.
  • the liquor and the pressure in the chamber corresponds to the temperature. This is the digesting period and it lasts until the lignin has been dissolved.
  • the liquor is then drained off again and the chips are thrust into the cooking tower where they cook in their absorbed liquor at normal pressure and without the addition of heat or more liquor.
  • the tower should be insulated to retain the heat in the digested mass. The digested mass is moved through the cooking tower by injections of later batches from the digester.
  • the pulp which is produced by this invention is novel and of superior quality. It is a slow pulp, itcontains a high proportion of hemicelluloses and it is refined by the usual refining steps of beating, etc., in about half to onequarter the'time required with pulps made by the alkaline processes of the prior art.
  • the cooking tower II is thermally insulated by a suitable insulating layer 12.
  • a valve 13 is niounted on the top of the cooking tower.
  • the shutting and opening positions of the valve 13 correspond to the shutting and opening positions of the valve 36.
  • the shutting position of these valves and the thermal insulation I! maintain the pressure and the temperature of the pulp in the cooking tower.
  • the process is economical of reagents and en ables the liquor from digestion to be used repeatedly.
  • the process is economical in fuel consumption because it requires far less fuel to accomplish a result equal to or superior to that attainable in the prior art for the equivalent quantity or pulp.
  • the total time required for the pulping of standard materials is less than that required by the processes of the prior art. It requires less than five minutes to reach the temperature at which lignin dissolves, and only. about half an hour is required for the cooking. This advantage is added to that whichis obtained in the quicker beating of the pulp.
  • the method of making cellulosic pulp that comprises impregnating natural ligno-cellulosic material with hot alkaline digesting liquor, immersing the material quickly in a large quantity of preheated alkaline digesting liquor under pressure at a temperature circa 170-180 C., digesting the material in said liquor, draining of! the liquid from the digested mass, and cooking the mass by its absorbed liquor.
  • the method of making cellulosic pulp that comprises impregnating natural cellulosic-ligneous material in an excess of alkaline digesting liquor having a concentration requisite to the dissolving of lignin and a temperature approaching 100 C., draining off the liquor, immersing the material suddenly in several times its weight of preheated alkaline digesting liquor which is at a temperature above that at which hemicellulose about 70 grams ofactive alkali per litre at a temperature approaching 100 degrees C.

Landscapes

  • Paper (AREA)
US696603A 1945-09-15 1946-09-12 Pulping process Expired - Lifetime US2582054A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR997965T 1945-09-15

Publications (1)

Publication Number Publication Date
US2582054A true US2582054A (en) 1952-01-08

Family

ID=9559060

Family Applications (1)

Application Number Title Priority Date Filing Date
US696603A Expired - Lifetime US2582054A (en) 1945-09-15 1946-09-12 Pulping process

Country Status (3)

Country Link
US (1) US2582054A (fr)
DE (1) DE843659C (fr)
FR (1) FR997965A (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2854334A (en) * 1954-11-08 1958-09-30 Hawaiian Dev Company Ltd Rapid kraft pulping process for bagasse and other fibrous, non-woody lignocellulosic plant materials
US3051611A (en) * 1959-11-16 1962-08-28 Cubano Inst Invest Hydrolysis of bagasse
US3347741A (en) * 1964-01-13 1967-10-17 Crane Co Feeder for solid materials
US3347739A (en) * 1962-09-15 1967-10-17 Ii George H Tomlinson Continuous sodium sulfide pulping of cellulosic material
US4451331A (en) * 1980-11-20 1984-05-29 Simmering-Graz-Pauker Aktiengesellschaft Process and apparatus for producing pulp
US11186948B2 (en) * 2016-05-27 2021-11-30 Fibratech Pte. Ltd Method and a system for production of high molecular weight lignin

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2849315A (en) * 1953-05-07 1958-08-26 Haglund Gustaf Digestion of wood
DE1034967B (de) * 1954-01-07 1958-07-24 Der Maschinenfabrik Von Theodo Kontinuierliches Verfahren und Vorrichtung zur Gewinnung von Halbzellstoffen aus Holz

Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1690954A (en) * 1927-01-20 1928-11-06 Spencer Edmondson Process for the extraction of cellulose or paper pulp from fibrous vegetable matter containing the same
US1887899A (en) * 1921-03-28 1932-11-15 Bradley Mckeefe Corp Production of pulp
US1949549A (en) * 1925-12-04 1934-03-06 Brown Co Refined cellulose pulp
US2041666A (en) * 1925-12-04 1936-05-19 Brown Co Cyclic process of treating alkaline pulps
US2047314A (en) * 1933-02-08 1936-07-14 Dreyfus Henry Lignocellulosic material
US2061305A (en) * 1934-10-13 1936-11-17 Sobemi Abreviation De Soc Belg Closing cap for bottles, etc.
US2137779A (en) * 1935-04-24 1938-11-22 Cellulose Res Corp Process of impregnating wood chips
US2159258A (en) * 1934-05-28 1939-05-23 Joaquin Julio De La Roza Sr Method and apparatus for digesting fibrous or cellular material
US2228349A (en) * 1936-11-28 1941-01-14 Cellulose Res Corp Treatment of woody material
US2230119A (en) * 1937-02-18 1941-01-28 Cellulose Res Corp Process of producing wood cellulose
US2229886A (en) * 1934-12-19 1941-01-28 Chemipulp Process Inc Method of digesting fibrous materials
US2265622A (en) * 1937-06-12 1941-12-09 Basler Hermann Method and apparatus for disintegrating fibrous materials
US2269985A (en) * 1938-08-12 1942-01-13 Cellulose Res Corp Manufacture of wood pulp
US2323194A (en) * 1940-08-07 1943-06-29 Beveridge James Brookes Apparatus for the production of pulp from cellulosic material
US2359543A (en) * 1940-09-24 1944-10-03 Kamyr Ab Apparatus for continuous digestion of fibrous material

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1887899A (en) * 1921-03-28 1932-11-15 Bradley Mckeefe Corp Production of pulp
US1949549A (en) * 1925-12-04 1934-03-06 Brown Co Refined cellulose pulp
US2041666A (en) * 1925-12-04 1936-05-19 Brown Co Cyclic process of treating alkaline pulps
US1690954A (en) * 1927-01-20 1928-11-06 Spencer Edmondson Process for the extraction of cellulose or paper pulp from fibrous vegetable matter containing the same
US2047314A (en) * 1933-02-08 1936-07-14 Dreyfus Henry Lignocellulosic material
US2159258A (en) * 1934-05-28 1939-05-23 Joaquin Julio De La Roza Sr Method and apparatus for digesting fibrous or cellular material
US2061305A (en) * 1934-10-13 1936-11-17 Sobemi Abreviation De Soc Belg Closing cap for bottles, etc.
US2229886A (en) * 1934-12-19 1941-01-28 Chemipulp Process Inc Method of digesting fibrous materials
US2137779A (en) * 1935-04-24 1938-11-22 Cellulose Res Corp Process of impregnating wood chips
US2228349A (en) * 1936-11-28 1941-01-14 Cellulose Res Corp Treatment of woody material
US2230119A (en) * 1937-02-18 1941-01-28 Cellulose Res Corp Process of producing wood cellulose
US2265622A (en) * 1937-06-12 1941-12-09 Basler Hermann Method and apparatus for disintegrating fibrous materials
US2269985A (en) * 1938-08-12 1942-01-13 Cellulose Res Corp Manufacture of wood pulp
US2323194A (en) * 1940-08-07 1943-06-29 Beveridge James Brookes Apparatus for the production of pulp from cellulosic material
US2359543A (en) * 1940-09-24 1944-10-03 Kamyr Ab Apparatus for continuous digestion of fibrous material

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2854334A (en) * 1954-11-08 1958-09-30 Hawaiian Dev Company Ltd Rapid kraft pulping process for bagasse and other fibrous, non-woody lignocellulosic plant materials
US3051611A (en) * 1959-11-16 1962-08-28 Cubano Inst Invest Hydrolysis of bagasse
US3347739A (en) * 1962-09-15 1967-10-17 Ii George H Tomlinson Continuous sodium sulfide pulping of cellulosic material
US3347741A (en) * 1964-01-13 1967-10-17 Crane Co Feeder for solid materials
US4451331A (en) * 1980-11-20 1984-05-29 Simmering-Graz-Pauker Aktiengesellschaft Process and apparatus for producing pulp
US4556452A (en) * 1980-11-20 1985-12-03 Simmering-Graz-Pauker Aktiengesellschaft Process and apparatus for producing pulp
US11186948B2 (en) * 2016-05-27 2021-11-30 Fibratech Pte. Ltd Method and a system for production of high molecular weight lignin

Also Published As

Publication number Publication date
DE843659C (de) 1952-07-10
FR997965A (fr) 1952-01-14

Similar Documents

Publication Publication Date Title
US3532594A (en) Method of digesting cellulosic material in steam phase
US3787241A (en) Apparatus for processing degradation of cellulosic materials
US2582054A (en) Pulping process
US2640774A (en) Production of cellulose pulp
US4849052A (en) Batch digester multi-stage pulping process
EP0498821B1 (fr) Methode et appareil pour deplacer les liqueurs epuisees dans un digesteur
US1991244A (en) Method and apparatus for digesting cellulose bearing material
US2229886A (en) Method of digesting fibrous materials
US3785920A (en) Method of treating raw cellulosic materials
NO178935B (no) Fremgangsmåte for fremstilling av kraftmasse
US1986760A (en) Process of producing cellulose from wood and other cellulose containing material and apparatus therefor
US1771598A (en) Process for digesting fibrous material
US3448002A (en) Pulping process
EP0554391B1 (fr) Procede de reduction en pate
US2008635A (en) Process of and apparatus for producing pulp
EP1702101B1 (fr) Procede discontinu de preparation de pate
US2175154A (en) Method for treating cellulosic material
US1052675A (en) Process of making cellulose.
US2749240A (en) Production of cellulose pulp
SU1331924A1 (ru) Способ получени целлюлозы дл химической переработки
US2882148A (en) Method of charging cellulose digesters
RU2198973C2 (ru) Способ получения целлюлозы
US1784849A (en) Pulpmaking and apparatus therefor
CN115852725B (zh) 蒸煮器及基于其的蒸煮制浆工艺
JP2005515319A (ja) セルロースパルプの製造方法及びその方法を実施する装置。