US3413189A - Method of performing hydrolysis and alkalic digestion of cellulosic fiber material with prevention of lignin precipitation - Google Patents
Method of performing hydrolysis and alkalic digestion of cellulosic fiber material with prevention of lignin precipitation Download PDFInfo
- Publication number
- US3413189A US3413189A US427814A US42781465A US3413189A US 3413189 A US3413189 A US 3413189A US 427814 A US427814 A US 427814A US 42781465 A US42781465 A US 42781465A US 3413189 A US3413189 A US 3413189A
- Authority
- US
- United States
- Prior art keywords
- liquor
- sieve
- fiber material
- conduit
- girdle
- 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
- 239000002657 fibrous material Substances 0.000 title description 36
- 230000029087 digestion Effects 0.000 title description 14
- 238000000034 method Methods 0.000 title description 13
- 229920005610 lignin Polymers 0.000 title description 9
- 230000007062 hydrolysis Effects 0.000 title description 7
- 238000006460 hydrolysis reaction Methods 0.000 title description 7
- 238000001556 precipitation Methods 0.000 title description 5
- 230000002265 prevention Effects 0.000 title description 3
- 239000000413 hydrolysate Substances 0.000 description 27
- 239000000203 mixture Substances 0.000 description 8
- 208000028659 discharge Diseases 0.000 description 7
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 7
- 239000003513 alkali Substances 0.000 description 5
- 230000002378 acidificating effect Effects 0.000 description 4
- 238000010438 heat treatment Methods 0.000 description 4
- 108010009736 Protein Hydrolysates Proteins 0.000 description 3
- 238000002419 base digestion Methods 0.000 description 3
- 238000007599 discharging Methods 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- 238000005406 washing Methods 0.000 description 3
- 239000003795 chemical substances by application Substances 0.000 description 2
- 239000000835 fiber Substances 0.000 description 2
- 230000003301 hydrolyzing effect Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 229920003043 Cellulose fiber Polymers 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 229920002678 cellulose Polymers 0.000 description 1
- 239000001913 cellulose Substances 0.000 description 1
- 230000003472 neutralizing effect Effects 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 239000011369 resultant mixture Substances 0.000 description 1
- 229910021653 sulphate ion Inorganic materials 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
- D21C3/00—Pulping cellulose-containing materials
- D21C3/22—Other features of pulping processes
- D21C3/24—Continuous processes
Definitions
- the present invention relates to a method of performing hydrolysis and a subsequent alkalic digestion of cellulosic fiber material in one and the same vessel through which the material is continuously advanced, hydrolysate and spent liquor being separated from the fiber material and discharged together.
- said risk is eliminated and an undisturbed operation is obtained by the feature that a portion of the digesting liquor is supplied in the vicinity of the spot where the hydrolysate and the spent liquor are mixed. Then the pH-value in the dis charge conduit will be sufficicntly high to prevent deposits therein.
- said liquor portion is chosen suflicient- 1y great to neutralize the acidic or acid-forming substances of the hydrolysate.
- the invention will be applied where the delignifying digestion is performed with the liquor flowing 50 counter-currently to the fiber material towards a discharge sieve inserted in the digester shell, through which sieve also hydrolysate is let off. Then the invention is applied in such a manner that said liquor portion is mixed into the hydrolysate and is drawn oil through said sieve together with the hydrolysate. Thereby the hydrolysate will not be in a position to cause precipitation of alkali lignin out of the spent liquor, but the discharge sieve will be maintained clean.
- the invention also relates to an upright cylindrical Vessel for performing prehydrolysis and alkalic digestion of fiber material axially fed therethrough, which vessel is provided with a sieve girdle inserted in the shell thereof and adapted for drawing-off prehydrolysate as well as Patented Nov. 26, 1968 spent digesting liquor.
- the same is characterised in that from a conduit for supplying the white liquor required for the digestion there is branchedotf a conduit which opens out into the vessel approximately at the level of said sieve girdle and preferably centrally of the cross-section of the vessel, so that the white liquor supplied through said last-mentioned conduit moves in a substantially horizontal and preferably radial direction towards the sieve girdle.
- 11 designates an upright cylindrical vessel of approximately uniform cross-section and a length of the order of 10 times the diameter.
- the vessel At its upper end the vessel is provided with known device for charging wood chips or some other suitable comminuted fiber material from which cellulose should be produced.
- the vessel At its lower end the vessel is provided with known devices for discharging the fiber material.
- the fiber material, the path of which through the vessel is designated by thick arrows 13, moves as a compact column axially downwards through the vessel, and during said movement it is first hydrolized, then delignified and finally washed as more closely described below.
- a sieve girdle 15 is inserted into the vessel shell. Prehydrolysis of the fiber material takes place in the part of the digester located above said sieve girdle. Therefore, either water or a diluted acid is fed to the top of the vessel through the conduit 17. Said liquid is drawn oil through a sieve girdle 19 inserted in the digester shell and is circulated by means of a pump 21 in a loop comprising a heating device 23 where heating takes place by means of steam supplied through the conduit 25, and which circulation loop has an orifice located centrally in the digester at approximately the same level as the sieve girdle 19. Due to said circulation the fiber material is heated to the temperature required for hydrolysation. The hydrolysate flows concurrently to the fiber material, as indicated by the arrows 25, and is discharged through the sieve girdle 15 and the conduit 27 connected thereto.
- a delignifying digestion by means of sulphate liquor or some other alkalic liquor is performed, Said liquor is supplied through a conduit 29 connected to a loop comprising a sieve girdle 31 inserted in the shell of the digester, a pump 33, a heating device 35 and a return conduit 37 which has an orifice located centrally in the digester approximately at the level of the sieve girdle 31.
- the circulating liquor is heated by steam supplied through the conduit 39 and after being distributed over the cross-section of the fiber material column the liquor passes upwardly through the same, as indicated by the arrows 41, i.e. counter-currently to the motion of the fiber material.
- the temperature and concentration of the white liquor as well as the velocities of the fiber material and the liquor are adapted such that the fiber material is completely delignified when passing the sieve girdle 31 and such that the greater part of the alkalic content of the liquor, while dissolving the lignin of the fiber material, is spent on its way up towards the sieve girdle 15.
- the black liquor thus obtained encounters the hydrolysate at the level of the sieve girdle 15 and departs to- 3 gether therewith through the conduit 27 connected to the sieve girdle.
- the digester In the zone below the sieve girdle 31 the digester is used for washing liquor out of the pulp by means of pure water or white water obtained from a subsequent washing filter.
- the -wash Water is supplied through the conduit 43 to the lower end of the digester. Somewhat higher up the same is drawn off through a sieve girdle 45 and is pumped by means of a pump 47 through a heating device 49 in which it is heated by steam supplied through the conduit 51, and then back to the digester into which the Wash water is supplied centrally and approximately at the same level as the sieve girdle 45.
- the wash water is forced upwards counter-currently to the fiber material, as indicated by the arrows 53, and displaces the digesting liquor which is forced out through the sieve girdle 15.
- the white liquor supplied through the conduit 29 is divided up into two portions, out of which the main portion, e.g. approximately two thirds, is introduced into the circulation loop 31, 33, 35, 37 and is driven counter-currently to the motion of the chips column up through the same to the sieve 15, whereas the remaining portion is branched oii into a conduit 55 which opens out centrally in the digester approximately at the level of the sieve girdle "15.
- the main portion e.g. approximately two thirds
- the latter white liquor portion is spread from the orifice of the conduit 55 radially outwards towards the sieve girdle 15, thereby being mixed with the hydrolysate flowing concurrently to the chips column and neutralizing said hydrolysate, at least partially, so that the same, when it is subsequently mixed also with the black liquor coming from below and departs together therewith through the sieve girdle 15 and the connected conduit 27,, does not cause deposits of alkali lignin contained in the black liquor.
- the orifice of the conduit 55 may be located at a level in the di gester somewhat above the level of the sieve girdle 15. Then the white liquid portion supplied through the conduit 55 will move a short distance concurrently to the fiber material before it is diverted together with the hydrolysate towards the sieve girdle in the shell of the digester.
- a pump 57 is inserted into a circulation conduit 59 connected to the sieve girdle .15 and also to the conduit 55 opening out at the centre of the digester. By means of said pump a heavy radial flow is maintained, whereby thewhite liquor is thoroughly mixed with the hydrolysate, thus equalizing the pH-value of the mixture.
- the conduit 55 may be provided with a plurality of outlets distributed over the cross-section of the vessel.
- the conduit 55 may also have a series of oulets located close to the shell of the vessel immediately above the sieve girdle 15. A part of the white liquor supplied to said peripheral outlets will flow along the inner surface of vessel and safeguard that the pH-value is maintained sufiiciently high at the uppermost part of the sieve girdle, through which pure hydrolysate else might pass and cause deposits.
- the white liquor portion used for raising the pH-value at the discharge spot can also be supplied at such a place that it moves counter-currently to the chips column.
- the invention will also be applicable in connection with prehydrolysis followed by one or more stages of concurrent delignifying digestion.
- Method of performing hydrolysis and a subsequent alkalic digestion of cellulosic fiber material in one and the same vessel wherein the material is continuously fed in which method hydrolysate and'spent digesting liquor are separated from the fiber material and discharged 4 together, characterised in that a portion of the fresh digesting liquor is supplied in the vicinity of the spot where hydrolysate and spent digesting liquor are mixed.
- An upright cylindrical vessel means for continuously charging a comminuted fiber material into one end of said vessel and moving the same axially through said vessel, means for supplying a hydrolizing agent to the fiber material charged into said vessel, a conduit for supplying an alkalic digesting liquor to the vessel for delignifying the fiber material therein, said conduit having an outlet into the vessel distant from the fiber material charging end therof, a sieve girdle inserted in the shell of the vessel intermediate and distant [from the fiber material charging end and said liquor conduit outlet, said sieve girdle being adapted for separating hydrolysate mixed with spent digesting liquor from the fiber material, a conduit connected to said sieve girdle for discharging said mixture from the vessel, a branch conduit connected to said digesting liquor supply conduit and having an outlet into the vessel located approximately at the level of said sieve girdle, whereby fresh alkalic liquor is added to the mixture of hydrolysate and spent digesting liquor in order to raise the pH-value thereof and prevent clogging of said sieve
- An upright prehydrolysis and alkali digestion vessel means for continuously axially feeding a cellulosic fiber material and a hydrolysis agent to one end of said vessel, a conduit for continuously charging an alkali digestion liquor to said vessel at a location distant from the fiber charging end therof, a sieve girdle inserted axially inside said vessel between said fiber feeding means and said digestion liquor conduit, a branch conduit from said digestion liquor conduit which opens into said vessel ap proximately at the level of said sieve girdle and prefer- 5 6 ably centrally of the cross-section of said vessel, a hy- References Cited drolysate and spent digestion liquor discharge conduit UNITED STATES PATENTS from said sieve girdle, and means for discharging said 3 145135 8/1964 Robertson et a1 162 43 fiber material from approximately the end of said vessel 3:200:032 8/1965 Richteret LL L1; 162 19 opposite said fiber material feeding means.
Landscapes
- Paper (AREA)
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
SE106064 | 1964-01-29 |
Publications (1)
Publication Number | Publication Date |
---|---|
US3413189A true US3413189A (en) | 1968-11-26 |
Family
ID=20257536
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US427814A Expired - Lifetime US3413189A (en) | 1964-01-29 | 1965-01-25 | Method of performing hydrolysis and alkalic digestion of cellulosic fiber material with prevention of lignin precipitation |
Country Status (4)
Country | Link |
---|---|
US (1) | US3413189A (de) |
DE (1) | DE1517151A1 (de) |
FI (1) | FI44515B (de) |
FR (1) | FR1423214A (de) |
Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4155806A (en) * | 1974-05-16 | 1979-05-22 | Skogsagarnas Industri Aktiebolag | Method for continuous alkaline delignification of lignocellulose material in two or more steps, the final of which with oxygen |
US4174997A (en) * | 1973-09-03 | 1979-11-20 | Kamyr Aktiebolag | Method and apparatus for continuous hydrolysis of cellulosic fiber material |
DE3301957A1 (de) * | 1982-01-22 | 1983-08-04 | Kamyr, Inc., 12801 Glens Falls, N.Y. | Verfahren und vorrichtung zur herstellung von kohlenhydratmaterial und kraftpulpe aus zerkleinertem zellulosefasermaterial |
US4668340A (en) * | 1984-03-20 | 1987-05-26 | Kamyr, Inc. | Method of countercurrent acid hydrolysis of comminuted cellulosic fibrous material |
US4941944A (en) * | 1984-07-13 | 1990-07-17 | Pierre A. Tonachel | Method for continuous countercurrent ogranosolv saccharification of comminuted lignocellulosic materials |
WO1995020065A1 (en) * | 1994-01-24 | 1995-07-27 | Sunds Defibrator Pori Oy | Production of prehydrolyzed pulp |
US5676795A (en) * | 1992-12-02 | 1997-10-14 | Voest-Alpine Industrieanlagenbau Gmbh | Process for the production of viscose pulp |
US5985096A (en) * | 1997-09-23 | 1999-11-16 | Ahlstrom Machinery Inc. | Vertical pulping digester having substantially constant diameter |
US20070079944A1 (en) * | 2004-04-20 | 2007-04-12 | The Research Foundation Of The State University Of New York | Product and processes from an integrated forest biorefinery |
EP1873303A3 (de) * | 1993-05-04 | 2008-06-18 | Andritz Inc. | Kontrolle gelöster Feststoffe bei der Zellstoffherstellung |
EP2014827A2 (de) | 2007-05-23 | 2009-01-14 | Andritz, Inc. | Eingefäßreaktorsystem für Hydrolyse und Digerierung von Hackschnitzeln mit chemischem erweitertem Waschverfahren |
US20090308383A1 (en) * | 2008-06-10 | 2009-12-17 | Andritz Inc. | Apparatus and method for hydrolysis of cellulosic material in a multi-step process to produce c5 and c6 sugars using a single vessel |
WO2010044732A1 (en) * | 2008-10-13 | 2010-04-22 | Metso Fiber Karlstad Ab | Method for preventing clogging in a strainer construction for a continuous digester |
US8192549B2 (en) | 2008-06-10 | 2012-06-05 | Andritz Inc. | Apparatus and method for hydrolysis of cellulosic material in a two-step process |
WO2012128901A1 (en) | 2011-03-18 | 2012-09-27 | Andritz Inc. | Vapor phase hydrolysis vessel and methods related thereto |
EP2003241A3 (de) * | 2007-05-23 | 2012-11-21 | Andritz, Inc. | Zweigefäßreaktorsystem und Verfahren zur Hydrolyse und Digerierung von Hackschnitzeln mit chemischem erweitertem Waschverfahren |
WO2013070160A1 (en) * | 2011-11-08 | 2013-05-16 | Reac Fuel Ab | Liquefaction of biomass at low ph |
US9738943B2 (en) | 2010-11-01 | 2017-08-22 | Renmatix, Inc. | Process for controlled liquefaction of a biomass feedstock by treatment in hot compressed water |
WO2019009792A1 (en) * | 2017-07-04 | 2019-01-10 | Valmet Ab | PROCESS FOR OPERATING A CONTINUOUS VERTICAL REACTOR COMPRISING A PRE-HYDROLYSIS AREA AND REACTOR DESIGN AS SUCH |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3145135A (en) * | 1962-09-04 | 1964-08-18 | Sonoco Products Co | Multi-stage pulping process |
US3200032A (en) * | 1961-12-23 | 1965-08-10 | Kamyr Ab | Continuous process for digesting cellulosic material |
US3243341A (en) * | 1961-11-20 | 1966-03-29 | Improved Machinery Inc | Continuous pulping apparatus |
-
1965
- 1965-01-25 US US427814A patent/US3413189A/en not_active Expired - Lifetime
- 1965-01-27 FI FI0187/65A patent/FI44515B/fi active
- 1965-01-29 FR FR3669A patent/FR1423214A/fr not_active Expired
- 1965-01-29 DE DE19651517151 patent/DE1517151A1/de active Pending
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3243341A (en) * | 1961-11-20 | 1966-03-29 | Improved Machinery Inc | Continuous pulping apparatus |
US3200032A (en) * | 1961-12-23 | 1965-08-10 | Kamyr Ab | Continuous process for digesting cellulosic material |
US3145135A (en) * | 1962-09-04 | 1964-08-18 | Sonoco Products Co | Multi-stage pulping process |
Cited By (33)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4174997A (en) * | 1973-09-03 | 1979-11-20 | Kamyr Aktiebolag | Method and apparatus for continuous hydrolysis of cellulosic fiber material |
US4155806A (en) * | 1974-05-16 | 1979-05-22 | Skogsagarnas Industri Aktiebolag | Method for continuous alkaline delignification of lignocellulose material in two or more steps, the final of which with oxygen |
DE3301957A1 (de) * | 1982-01-22 | 1983-08-04 | Kamyr, Inc., 12801 Glens Falls, N.Y. | Verfahren und vorrichtung zur herstellung von kohlenhydratmaterial und kraftpulpe aus zerkleinertem zellulosefasermaterial |
US4436586A (en) | 1982-01-22 | 1984-03-13 | Kamyr, Inc. | Method of producing kraft pulp using an acid prehydrolysis and pre-extraction |
US4668340A (en) * | 1984-03-20 | 1987-05-26 | Kamyr, Inc. | Method of countercurrent acid hydrolysis of comminuted cellulosic fibrous material |
US4941944A (en) * | 1984-07-13 | 1990-07-17 | Pierre A. Tonachel | Method for continuous countercurrent ogranosolv saccharification of comminuted lignocellulosic materials |
US5676795A (en) * | 1992-12-02 | 1997-10-14 | Voest-Alpine Industrieanlagenbau Gmbh | Process for the production of viscose pulp |
EP1873303A3 (de) * | 1993-05-04 | 2008-06-18 | Andritz Inc. | Kontrolle gelöster Feststoffe bei der Zellstoffherstellung |
WO1995020065A1 (en) * | 1994-01-24 | 1995-07-27 | Sunds Defibrator Pori Oy | Production of prehydrolyzed pulp |
US5589033A (en) * | 1994-01-24 | 1996-12-31 | Sunds Defibrator Pori Oy | Production of prehydrolyzed pulp |
AU688447B2 (en) * | 1994-01-24 | 1998-03-12 | Sunds Defibrator Pori Oy | Production of prehydrolyzed pulp |
US5985096A (en) * | 1997-09-23 | 1999-11-16 | Ahlstrom Machinery Inc. | Vertical pulping digester having substantially constant diameter |
US9945073B2 (en) | 2004-04-20 | 2018-04-17 | The Research Foundation For The State University Of New York | Methods of producing a paper product |
US20070079944A1 (en) * | 2004-04-20 | 2007-04-12 | The Research Foundation Of The State University Of New York | Product and processes from an integrated forest biorefinery |
US8940133B2 (en) | 2004-04-20 | 2015-01-27 | The Research Foundation For The State University Of New York | Product and processes from an integrated forest biorefinery |
US8668806B2 (en) | 2004-04-20 | 2014-03-11 | The Research Foundation Of The State University Of New York | Product and processes from an integrated forest biorefinery |
US9683329B2 (en) | 2004-04-20 | 2017-06-20 | The Research Foundation For The State University Of New York | Methods of producing a paper product |
US9273431B2 (en) | 2004-04-20 | 2016-03-01 | The Research Foundation For The State University Of New York | Product and processes from an integrated forest biorefinery |
US8317975B2 (en) * | 2004-04-20 | 2012-11-27 | The Research Foundation Of The State University Of New York | Product and processes from an integrated forest biorefinery |
EP2003241A3 (de) * | 2007-05-23 | 2012-11-21 | Andritz, Inc. | Zweigefäßreaktorsystem und Verfahren zur Hydrolyse und Digerierung von Hackschnitzeln mit chemischem erweitertem Waschverfahren |
RU2463402C2 (ru) * | 2007-05-23 | 2012-10-10 | Андритц Инк. | Реакторная система с одной емкостью для гидролиза и варки древесной крошки с химически усиленным способом промывки |
EP2014827A3 (de) * | 2007-05-23 | 2012-11-21 | Andritz, Inc. | Eingefäßreaktorsystem für Hydrolyse und Digerierung von Hackschnitzeln mit chemischem erweitertem Waschverfahren |
JP2009052188A (ja) * | 2007-05-23 | 2009-03-12 | Andritz Inc | 化学物質増強洗浄方法を用いた木材チップの加水分解および蒸解のための単一槽反応装置系 |
EP2014827A2 (de) | 2007-05-23 | 2009-01-14 | Andritz, Inc. | Eingefäßreaktorsystem für Hydrolyse und Digerierung von Hackschnitzeln mit chemischem erweitertem Waschverfahren |
US8246750B2 (en) | 2008-06-10 | 2012-08-21 | Andritz Inc. | Apparatus and method for hydrolysis of cellulosic material in a multi-step process to produce C5 and C6 sugars using a single vessel |
US8192549B2 (en) | 2008-06-10 | 2012-06-05 | Andritz Inc. | Apparatus and method for hydrolysis of cellulosic material in a two-step process |
US20090308383A1 (en) * | 2008-06-10 | 2009-12-17 | Andritz Inc. | Apparatus and method for hydrolysis of cellulosic material in a multi-step process to produce c5 and c6 sugars using a single vessel |
WO2010044732A1 (en) * | 2008-10-13 | 2010-04-22 | Metso Fiber Karlstad Ab | Method for preventing clogging in a strainer construction for a continuous digester |
US9738943B2 (en) | 2010-11-01 | 2017-08-22 | Renmatix, Inc. | Process for controlled liquefaction of a biomass feedstock by treatment in hot compressed water |
WO2012128901A1 (en) | 2011-03-18 | 2012-09-27 | Andritz Inc. | Vapor phase hydrolysis vessel and methods related thereto |
WO2013070160A1 (en) * | 2011-11-08 | 2013-05-16 | Reac Fuel Ab | Liquefaction of biomass at low ph |
US9783565B2 (en) | 2011-11-08 | 2017-10-10 | Renmatix, Inc. | Liquefaction of biomass at low pH |
WO2019009792A1 (en) * | 2017-07-04 | 2019-01-10 | Valmet Ab | PROCESS FOR OPERATING A CONTINUOUS VERTICAL REACTOR COMPRISING A PRE-HYDROLYSIS AREA AND REACTOR DESIGN AS SUCH |
Also Published As
Publication number | Publication date |
---|---|
FI44515B (de) | 1971-08-02 |
FR1423214A (fr) | 1966-01-03 |
DE1517151A1 (de) | 1969-06-19 |
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