US1991244A - Method and apparatus for digesting cellulose bearing material - Google Patents
Method and apparatus for digesting cellulose bearing material Download PDFInfo
- Publication number
- US1991244A US1991244A US690406A US69040633A US1991244A US 1991244 A US1991244 A US 1991244A US 690406 A US690406 A US 690406A US 69040633 A US69040633 A US 69040633A US 1991244 A US1991244 A US 1991244A
- Authority
- US
- United States
- Prior art keywords
- digesting
- liquor
- vessel
- digested
- zone
- 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
Links
- 239000000463 material Substances 0.000 title description 97
- 238000000034 method Methods 0.000 title description 32
- 229920002678 cellulose Polymers 0.000 title description 27
- 239000001913 cellulose Substances 0.000 title description 27
- 230000008569 process Effects 0.000 description 20
- 239000000126 substance Substances 0.000 description 14
- 239000002657 fibrous material Substances 0.000 description 13
- 239000000243 solution Substances 0.000 description 13
- 230000029087 digestion Effects 0.000 description 6
- 239000002253 acid Substances 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- 238000004064 recycling Methods 0.000 description 4
- 239000007799 cork Substances 0.000 description 3
- 230000004044 response Effects 0.000 description 3
- 238000004061 bleaching Methods 0.000 description 2
- 238000010924 continuous production Methods 0.000 description 2
- 238000007599 discharging Methods 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000011148 porous material Substances 0.000 description 2
- 238000011084 recovery Methods 0.000 description 2
- 244000283070 Abies balsamea Species 0.000 description 1
- 235000007173 Abies balsamea Nutrition 0.000 description 1
- 244000198134 Agave sisalana Species 0.000 description 1
- 241000609240 Ambelania acida Species 0.000 description 1
- 235000017166 Bambusa arundinacea Nutrition 0.000 description 1
- 235000017491 Bambusa tulda Nutrition 0.000 description 1
- 244000025254 Cannabis sativa Species 0.000 description 1
- 235000012766 Cannabis sativa ssp. sativa var. sativa Nutrition 0.000 description 1
- 235000012765 Cannabis sativa ssp. sativa var. spontanea Nutrition 0.000 description 1
- 240000000491 Corchorus aestuans Species 0.000 description 1
- 235000011777 Corchorus aestuans Nutrition 0.000 description 1
- 235000010862 Corchorus capsularis Nutrition 0.000 description 1
- 229920000742 Cotton Polymers 0.000 description 1
- 244000082204 Phyllostachys viridis Species 0.000 description 1
- 235000015334 Phyllostachys viridis Nutrition 0.000 description 1
- 241000218657 Picea Species 0.000 description 1
- 235000008331 Pinus X rigitaeda Nutrition 0.000 description 1
- 241000018646 Pinus brutia Species 0.000 description 1
- 235000011613 Pinus brutia Nutrition 0.000 description 1
- 241000209504 Poaceae Species 0.000 description 1
- 241000219000 Populus Species 0.000 description 1
- 241000219492 Quercus Species 0.000 description 1
- 240000000111 Saccharum officinarum Species 0.000 description 1
- 235000007201 Saccharum officinarum Nutrition 0.000 description 1
- 240000008042 Zea mays Species 0.000 description 1
- 235000005824 Zea mays ssp. parviglumis Nutrition 0.000 description 1
- 235000002017 Zea mays subsp mays Nutrition 0.000 description 1
- 230000009471 action Effects 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 239000010905 bagasse Substances 0.000 description 1
- 239000011425 bamboo Substances 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 235000009120 camo Nutrition 0.000 description 1
- 230000001413 cellular effect Effects 0.000 description 1
- 235000005607 chanvre indien Nutrition 0.000 description 1
- 238000004040 coloring Methods 0.000 description 1
- 229940000425 combination drug Drugs 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 235000005822 corn Nutrition 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 238000010790 dilution Methods 0.000 description 1
- 239000012895 dilution Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000011487 hemp Substances 0.000 description 1
- 239000008240 homogeneous mixture Substances 0.000 description 1
- 238000005470 impregnation Methods 0.000 description 1
- 230000002401 inhibitory effect Effects 0.000 description 1
- 230000008774 maternal effect Effects 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 238000005517 mercerization Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 238000012856 packing Methods 0.000 description 1
- 230000000750 progressive effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000005507 spraying Methods 0.000 description 1
- 239000010902 straw Substances 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
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
-
- 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
- D21C7/02—Rotary digesters
Definitions
- One object of my invention is to provide an.
- Another object of my invention is to provide a process of digesting cellulose bearing material in which the material to be digested is compacted to form of itself a cork or plug capable of withstanding the pressure existing within the digesting zone.
- Another object of my invention is to provide a method for digesting cellulose bearing material in which a high volumetric density may be employed in order to increase the efliciency and output of the process and the quality of the product.
- Another object is to provide means for moving the highly compacted material forward as the digestion proceeds.
- a further object of my invention is to provide a method for reducing the time of digestion.
- Still another object of my invention is to provide a method of digesting in which a predetermined level is maintained within the digesting zone in order to produce uniform digestion throughout the digesting material.
- Another object of my-invention is to provide a method of digesting cellulose bearing material in which the rate of feeding boththe cellulose bearing material and the digesting liquor, and the rate of withdrawing the digesting material are controlled by the level of the digesting material within the digesting zone.
- Figure 1 is a diagrammatic plan view of an apparatus capable of carrying out the process of my invention.
- Figure 2 is a diagrammatic elevation of the apparatus shown in Figure 1.
- Figure 3 is a diagrammatic sectional elevation of the apparatus shown in Figure 1 cmbodyin'g one form of my invention and capable of carrying out my process.
- my invention contemplates the provision of a substantially horizontally inclined elongated digesting vessel having a cross sectional area not less than one and one quarter and not more than six times the cross sectional area of the restricted inlet leading to the vessel.
- a reciprocating pistonal plunger is adapted to force the material being fed through the restricted inlet which, by vir-
- the restricted inlet is tapered and first tue of its taper, compresses or compacts the material being fed.
- the digesting vessel itself is provided with a steam or vapor dome at the top thereof and communicating therewith.
- the digesting ,vessel is positioned substantially horizontally, and slightly higher at the inlet end than at the outlet end in order to permit. a downward flow of the material.
- the vessel- is proportioned so that it is substantially thirty times or more as long as its" diameter. At'suitable places along the shell I provide expansion means for permitting longitudinal expansion of the vessel.
- the steam or vapor dome accommodates slight changes in thevolume of the liquid, while at the same time permitting the digesting vessel proper to be completely filled, with material at high density.
- a perforated cylinder provided with means to rotate the same.
- the portion of the cylinder nearest the inlet for the material to be digested is tapered and given the shape of a frustrum of a cone.
- the cylinder is constantly rotated to insure a thorough mingling of the material to be digested with the digesting liquor, and to move the mass forward.
- a maximum of 173 C. for the alkaline process which I prefer to be a maximum of 173 C. for the alkaline process, and 150 C.
- I provide means for continuously withdrawing a portion of the liquor from near the outlet end of the digesting vessel, heating the withdrawn liquor and returning it to the digestor, preferably at a point within the first third of the length of the vessel.
- I feed the digesting liquor into the digesting vessel at a point in the vicinity of the conical portion of the rotating cylinder.
- I provide means for introducing into the fresh incoming liquor a portion of the heated, recycled liquor. I prefer to sufiiciently heat the recycled liquor so that the temperature of the resulting mixture entering the digesting zone will be about 110 C. for the acid process or about 140 C. for the alkaline process.
- I provide a temperature control means for governing the amount of heat passing through the heat exchanger.
- a digester shell 1 may be of any suitable construction and provided at intervals along its length with expansion and sealing joints 2. Near the inlet end of the shell 1 and communicating therewith I provide a vapor or steam dome-3 fitted with a relief valve 4. Mounted within the shell 1, in suitable bearings 5, I provide a cylinder 6 provided at its inlet end with a conical portion 7. The cylinder is provided with means for rotating the same. In the modification shown in the drawings, a ring gear 8 is secured to the cylinder as shown and adapted to be driven from electrical motor 9 which drives pinion 10 through reduction gears 11. If desired, the cylinder 6 may be driven from a number of points. The cylinder is provided at suitably spaced points along its length with perforations 12.
- perforations are of such size as to retain the fibrous material within the cylinder, while permitting the digesting liquor to pass through for recirculation, as will be hereinafter more fully described.
- the perforations near the inlet end areabout one fourth inch in diameter, while those near the outer end are one sixteenth inch in diameter. The size of the perforations may be varied as desired.
- the conical portion 7 of the cylinder 6 bears against the inlet member 14. It will be observed that the inlet member 14 communicates with a hopper 15 and that portion of the inlet passage 16 extending from the hopper 15 toward the inlet end of the digester converges to form a restricted throat 1'7. From the throat 17 to the digesting vessel, that portion of the inlet passage 18 diverges.
- a conveyor belt 19 is adapted to feed cellulose bearing material, which may be such woods as spruce, pine, fir, oak, hemlock, poplar, or others in combination or alone, or fibrous grasses including sugar cane fibre, bagasse, corn stalk, bamboo, straw, cotton stalks, fiax stalks, jute, hemp, sisal, manila, and the like.
- the cellulose bearing material is comminuted and fed to the conveying mechanism which is driven by any suitable means as for example motor 20.
- the throat of the hopper 15 is provided with a jacket 21 provided with openings 22.
- a chemical solution tank 23 is placed in communication with the jacket 21 by means of pipe 24.
- a pump 25 driven by a suitable motor 26 is adapted to pump chemical solution from tank 23 to jacket 21 for spraying through the perforations 22 as can readily be seen by reference to Figure 3.
- the fibrous material will become impregnated with chemical solution before passing into the inlet passage.
- a reciprocating plunger 2'7 driven by any suitable means is adapted to ram or compact the chemically impregnated cellulose bearing material through the converging portion 16 of the inlet passage. The packing of the chemically impregnated cellulose bearing material will increase its density at the same time forcing chemical solution through the pores of fibrous material.
- the column of compressed material will be at least as dense as a solid piece of wood, while possessing a tendency to spring apart.
- the density to which the material is compressed will be in the neighborhood of 35 pounds of fibrous material per cubic foot.
- This highly compressed column of fibrous material being forced through the restricted portion 17 into the diverging portion '18 will form an advancing, continuous cork or plug, of a density of at least 20- pounds per cubic foot of dry fibrous material, adapted to withstand the pressure existing within the digesting zone.
- the compressed material emerges from the inlet passage 14 into the conical portion 1 of the cylinder 6 in the digesting zone, it will expand to a density of 20 to 18 pounds or lessper cubic It will be observed that foot of dry fibrous material.
- any suitable point in the digesting zone I withdraw a portion of the digesting liquor through line 35, which is controlled by valve 36, and pump the same b g means of pump 3'1 through line 38 to a'heat exchanger 39.
- Any suitable heating medium as for example steam, passes through line 40, through valve 41, through the heat exchanger 39 in heat exchange with the withdrawn liquor, and passing out through-line 42.
- the 'rate of heat exchange is such that in the alkaline process the recycle liquor passing through the heat exchanger will be heated to about 173 -C. while in the acid process it will be heated to about 150 C.
- the heated recycle liquor will leave the heat exchanger through line 43 and pass through line 44 through valve 45 into the digesting zone.
- the point of introduction of the recycled, heated liquor is preferable within the first third of the length of the digesting zone.
- a bleeder line 46 controlled by valve 47 is adapted to bypass a portion of the heated recycle liquor into line 33 for admixing with the fresh incoming liquor.
- the velocity of the recycling will be relatively low so as not to interfere with the forward movement of the digesting material through the digesting zones
- the rotation of the inner cylinder 12 will maintain a smooth homogeneous mixture, making for a uniform product and, at the same timefpermitting the high density of fibrous material to be employed.
- the liquor for recycling may be withdrawn from the lower portion of the steam or vapor dome 3 or any other suitable pointv in the process.
- the cellulose material has been cooked by passage through the digesting zone, which as pointed out above, may be somewhat inclined to facilitate the passage of the digesting material therethrough, it is deflected downwardly by the end wall 50 of the digester and passed into conduit 51 to a volumetric valve 52 which-is mounted on shaft 53 adapted to be rotated by motor 54.
- the valve 52 will be driven at a speed consistent with the grade of pulp being produced. If the pulp is under cooked. the valve may be slowed down by adjusting motor ,54'. If it is over cooked, it may be stepped'up.
- the volumetric discharge valve admits into a downwardly extending passageway 54 which discharges tangentially of cylindrical baflle 55 which extends into the blow tank 56.
- the blow tank acts as a .gas, steam and vapor separator, the vapors and gases passing upwardly through the passage 57, through condenser 58.
- the bottom of the blow tank 56 is fitted with an inlet pipe 59 into which additional liquor may be added to dilute the digested stock in order to enable it to flow out of pipe 60 and be handled by pump 61 so that it may pass through line 62 in the diluted condition, where it is handled by washersv in the usual manner known to the art.
- An agitator 63 - driven by a suitable motor 54 insures that the digested mass is kept thoroughly agitated to enable its being handled in a sufiiciently diluted form enabling it to flow.
- a thermocouple '70 adapted to make and break a circuit operat- It will be observed that, by this arrangement, if the temperature within the digesting zone falls below a predetermined point, the valve 41 will be opened further to admit a greater supply of heating medium to the heat exchanger and, if the temperature be above a predetermined point, the arrangement is such that the valve 41 will tend to close, thus reducing the supply of heat furnished to the circulating recycle liquor.
- the level of the digesting liquor will-rise within the dome 3 to actuate float 72 which controls, through any suitable arrangement, rheostats 73 and '74. s
- I am enabled to continuously treat cellulose bearing material at a very high density to produce a uniform product high in quality with a maximum of economy.
- I disseminate digesting chemical through the fibrous material before it enters the digesting zone, thus aiding in digestion and increasing the quality of the product.
- My process conserves heat in the entire system and my apparatus gives a very close heat control, resulting in the formation of a uniform product.
- a digesting apparatus including in combination a digesting chamber, an elongated cylinder positioned within said chamber, means for rotating said cylinder, means for introducing the material to be digested into said cylinder and means for withdrawing digested material from said cylinder.
- a digesting apparatus comprising in combination-an elongated substantially horizontal vessel formed with an enlarged chamber communicating with the upper portion thereof, means for introducing material to be digested into said vessel, and means responsive to the level of the material in said enlarged chamber for controlling said material introducing means.
- a digesting apparatus comprising in combination an elongated substantially horizontal vessel formed with an enlarged chamber communicating with the upper portion thereof, means for withdrawing digested material from said vessel, and means responsive to the level of the material in said enlarged chamber for controlling said withdrawing means.
- a digesting apparatus comprising in combination an elongated substantially horizontal vessel formed with an enlarged chamber communicating with the upper portion thereof, means for introducing material to be digested into said vessel, means for withdrawing the digested material from said vessel and means responsive to the level of the material within said enlarged chamber for controlling said material introducing and material withdrawing means.
- a digesting apparatus comprising in combination an elongated substantially horizontal vessel, a cylinder positioned therein and provided with perforations, means for rotating said cylinder, means for introducing-material to be digested into said cylinder, means for introducing digesting liquor into said vessel, heat ex changingmeans, means for continuously withdrawing liquor from the digesting vessel, means for passing withdrawn liquor through said heat exchanging means, and means for reintroducing it into said vessel.
- a digesting apparatus as in claim 7 where in communicating means are provided between said reintroducing means and said digesting liquor introducing means, whereby a portion of the heated withdrawn liquor may be admixed with the fresh incoming liquor.
- a digesting apparatus as in claim 7 provided with means to supply heat to said heat exchanging means, and means responsive to the temperature within said vessel for controlling said heat supplying means.
- a process of digesting cellulose bearing material with digesting liquor in a digesting zone including the step of controlling the withdrawal of the digested material in response to the level of material within said zone.
- a process of digesting cellulose bearing material with digesting liquor in a digesting zone including the steps of continuously introducing the material to be digested into the digesting zone and controlling the rate of introduction in response to the level of material within said zone.
- a continuous process of digesting cellulose bearing material in a digesting zone including the steps of continuously introducing material to be digested and digesting liquor into said zone, continuously withdrawing digested material from said zone, and controlling the rates of introduction of the material introduced and the digesting liquor and the rate of withdrawing the digested material in response to the level of the material within said zone.
- a continuous process of digesting cellulose bearing material in a digesting zone including the steps of introducing material to be digested and fresh digesting liquor into said zone,
- a process of digesting cellulose bearing material in a digesting zone including the step of withdrawing digested material from said zone at a rate which is a function of the level of the material within said zone.
- a digesting apparatus comprising in combination an elongated digesting vessel provided with an enlarged chamber communicating therewith, an inlet for'said vessel, said inlet being formed with a restriction and having opposite tapered walls extending from said restriction whereby a converging-diverging passageway is formed, a hopper for the material to be digested communicating with said passageway, a chemical solution feeding means adapted to inject a solution into said hopper, a reciprocating plunger for compacting material from said hopper through said inlet into the digesting vessel, a cylinder positioned within said vessel, said cylinder being provided with perforations, means for rotating said cylinder, means for introducing digesting liquor into said vessel, means for continuously withdrawing a portion of the digesting liquor, means forheating the withdrawn liquor and means for reintroducing the heated liquor into said vessel.
- a continuous digesting apparatus including in combination a vessel, an unobstructed elongated container positioned within said vessel, means for rotating said container, means for introducing the material to be digested into said container and means for withdrawing di"! gested material from said container.
- a continuous apparatus including in combination a vessel, an unobstructed elongated container positioned within said vessel, means for rotating said container, means for introducing the material to be digested into said container and means for withdrawing digested maternal from said container and means synchronizing said introducing means and said withdrawal means.
- a digesting apparatus comprising in combination an elongated substantially horizontal vessel formed with an enlarged chamber communicating with the upper portion thereof, means for introducing material to be digested into said vessel, means for withdrawing the digested material from said vessel, and means responsive to the level of the material within said enlarged chamber for controlling said material introducing and material withdrawing means.
- a digesting apparatus comprising in com-- bination an elongated substantially horizontal vessel having a dome, a rotatable container in the vessel and means for introducing material to be digested and withdrawal means for discharging the digested material, driving connections for rotating the cylinder positioned Within and beneath the dome and means for controlling the supply and discharge of material to and from the digestion vessel.
- a digesting apparatus including in combination a digesting vessel, an unobstructed elongated container positioned within said vessel, means for rotating said container, means for introducing the material to be digested into said container and means for withdrawing digested material from said container and means synchronizing said introducing means and said withdrawal means.
- a digesting apparatus including in combination a digesting vessel, an elongated container positioned within said vessel, .means forintroducing a chemical solution to said elongated container and a vapor chamber having vapor relief means above said digesting vessel.
- An apparatus for digesting fibrous or cellular material comprising a rotating digesting container, a vapor dome communicating with said container, an inlet adapted to compact material during its passage through the inlet to form a closure plug for said container, means for compacting material through said inlet and means for discharging digested material.
Landscapes
- Paper (AREA)
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
NL44553D NL44553C (xx) | 1933-09-21 | ||
US690406A US1991244A (en) | 1933-09-21 | 1933-09-21 | Method and apparatus for digesting cellulose bearing material |
FR778828D FR778828A (fr) | 1933-09-21 | 1934-09-20 | Procédé et appareil pour le défibrage de matières fibreuses ou cellulaires |
GB27208/34A GB428120A (en) | 1933-09-21 | 1934-09-21 | Improvements relating to the pulping of fibrous and cellular materials |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US690406A US1991244A (en) | 1933-09-21 | 1933-09-21 | Method and apparatus for digesting cellulose bearing material |
Publications (1)
Publication Number | Publication Date |
---|---|
US1991244A true US1991244A (en) | 1935-02-12 |
Family
ID=24772315
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US690406A Expired - Lifetime US1991244A (en) | 1933-09-21 | 1933-09-21 | Method and apparatus for digesting cellulose bearing material |
Country Status (4)
Country | Link |
---|---|
US (1) | US1991244A (xx) |
FR (1) | FR778828A (xx) |
GB (1) | GB428120A (xx) |
NL (1) | NL44553C (xx) |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE828345C (de) * | 1941-04-19 | 1952-01-17 | Johannes Jung | Verfahren und Vorrichtung zur Gewinnung von Fasergut als Ausgangsmaterial fuer die Herstellung von Faserstofferzeugnissen oder Zellstoff |
US2592983A (en) * | 1945-07-02 | 1952-04-15 | Hildebrandt Paul G Von | Apparatus for separating cooking liquor from pulp |
US2616802A (en) * | 1949-07-26 | 1952-11-04 | Pandia Inc | Fiberizing lignocellulose steamed under pressure and apparatus |
US2709652A (en) * | 1949-11-08 | 1955-05-31 | Celanese Corp | Acid sulfite pulping |
US2730426A (en) * | 1951-06-20 | 1956-01-10 | Cellulose Dev Corp Ltd | Treating vegetable fibrous material with chlorine gas |
US2858213A (en) * | 1956-04-20 | 1958-10-28 | Condi Engineering Corp | Wood chip digestion |
US2870009A (en) * | 1955-06-15 | 1959-01-20 | Kamyr Ab | Method and apparatus for the separation of liquids from cellulosic pulp |
US2878117A (en) * | 1955-12-02 | 1959-03-17 | Improved Machinery Inc | Particle advancing apparatus |
DE1074390B (de) * | 1959-01-05 | 1960-01-28 | Ing Wilhelm Klau ditz Braunschweig Dr | Verfahren zur Herstellung von Papierstoff aus fasei parallel geschnittenen Holzfolien |
DE1088335B (de) * | 1957-02-21 | 1960-09-01 | West Virginia Pulp & Paper Co | Verfahren zum kontinuierlichen Aufschliessen von Holzschnitzeln |
US2953202A (en) * | 1955-07-15 | 1960-09-20 | Pandia Inc | Continuous digester |
US2961041A (en) * | 1956-08-06 | 1960-11-22 | Masonite Corp | Apparatus for disintegration of fibrous material |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
NL238470A (xx) * | 1958-04-24 |
-
0
- NL NL44553D patent/NL44553C/xx active
-
1933
- 1933-09-21 US US690406A patent/US1991244A/en not_active Expired - Lifetime
-
1934
- 1934-09-20 FR FR778828D patent/FR778828A/fr not_active Expired
- 1934-09-21 GB GB27208/34A patent/GB428120A/en not_active Expired
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE828345C (de) * | 1941-04-19 | 1952-01-17 | Johannes Jung | Verfahren und Vorrichtung zur Gewinnung von Fasergut als Ausgangsmaterial fuer die Herstellung von Faserstofferzeugnissen oder Zellstoff |
US2592983A (en) * | 1945-07-02 | 1952-04-15 | Hildebrandt Paul G Von | Apparatus for separating cooking liquor from pulp |
US2616802A (en) * | 1949-07-26 | 1952-11-04 | Pandia Inc | Fiberizing lignocellulose steamed under pressure and apparatus |
US2709652A (en) * | 1949-11-08 | 1955-05-31 | Celanese Corp | Acid sulfite pulping |
US2730426A (en) * | 1951-06-20 | 1956-01-10 | Cellulose Dev Corp Ltd | Treating vegetable fibrous material with chlorine gas |
US2870009A (en) * | 1955-06-15 | 1959-01-20 | Kamyr Ab | Method and apparatus for the separation of liquids from cellulosic pulp |
US2953202A (en) * | 1955-07-15 | 1960-09-20 | Pandia Inc | Continuous digester |
US2878117A (en) * | 1955-12-02 | 1959-03-17 | Improved Machinery Inc | Particle advancing apparatus |
US2858213A (en) * | 1956-04-20 | 1958-10-28 | Condi Engineering Corp | Wood chip digestion |
US2961041A (en) * | 1956-08-06 | 1960-11-22 | Masonite Corp | Apparatus for disintegration of fibrous material |
DE1088335B (de) * | 1957-02-21 | 1960-09-01 | West Virginia Pulp & Paper Co | Verfahren zum kontinuierlichen Aufschliessen von Holzschnitzeln |
DE1074390B (de) * | 1959-01-05 | 1960-01-28 | Ing Wilhelm Klau ditz Braunschweig Dr | Verfahren zur Herstellung von Papierstoff aus fasei parallel geschnittenen Holzfolien |
Also Published As
Publication number | Publication date |
---|---|
NL44553C (xx) | |
GB428120A (en) | 1935-05-07 |
FR778828A (fr) | 1935-03-25 |
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