WO2010143997A1 - Method for precipitating lignin from black liquor by utilizing waste gases - Google Patents
Method for precipitating lignin from black liquor by utilizing waste gases Download PDFInfo
- Publication number
- WO2010143997A1 WO2010143997A1 PCT/SE2009/000291 SE2009000291W WO2010143997A1 WO 2010143997 A1 WO2010143997 A1 WO 2010143997A1 SE 2009000291 W SE2009000291 W SE 2009000291W WO 2010143997 A1 WO2010143997 A1 WO 2010143997A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- lignin
- stage
- acid
- black liquor
- acidification stage
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07G—COMPOUNDS OF UNKNOWN CONSTITUTION
- C07G1/00—Lignin; Lignin derivatives
-
- 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
- D21C11/00—Regeneration of pulp liquors or effluent waste waters
- D21C11/0007—Recovery of by-products, i.e. compounds other than those necessary for pulping, for multiple uses or not otherwise provided for
-
- 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
- D21C11/00—Regeneration of pulp liquors or effluent waste waters
- D21C11/0085—Introduction of auxiliary substances into the regenerating system in order to improve the performance of certain steps of the latter, the presence of these substances being confined to the regeneration cycle
-
- 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
- D21C11/00—Regeneration of pulp liquors or effluent waste waters
- D21C11/04—Regeneration of pulp liquors or effluent waste waters of alkali lye
Definitions
- This invention relates to a method for lignin separation from spent cooking liquor, called original black liquor, using a 2-stage acidic separation process.
- the invention is based upon the finding that the H 2 S gases that are emitted from the reslurrying tank also contains a large amount of residual carbon dioxide, CO 2 .
- CO 2 residual carbon dioxide
- These compounds reacts with the acidifier and forms carbon dioxide (CO2) and hydrogen sulfide (H 2 S), according to:
- This invention relates to a two-stage acidic separation process and the scientific definition of acidity is as follows.
- Reactions of acids are often generalized in the form HA H + + A " , where HA represents the acid and A " is the conjugate base.
- Acid-base conjugate pairs differ by one proton, and can be interconverted by the addition or removal of a proton (protonation and deprotonation, respectively).
- the acid can be the charged species and the conjugate base can be neutral in which case the generalized reaction scheme could be written as HA + H + + A.
- the equilibrium constant K is an expression of the equilibrium concentrations of the molecules or ions in solution.
- Brackets indicate concentration, such that [H 2 O] means the concentration OfH 2 O.
- the acid dissociation constant K 3 is generally used in the context of acid-base reactions.
- the numerical value of K a is equal to the concentration of the products over the concentration of the reactants, where the reactant is the acid (HA) and the products are the conjugate base and H + .
- strong acid embraces any acidifier comparable to sulfuric acid in aspects of acidic strength, i.e. a pK a number in the order of -3, i.e. in the negative range and preferably in the range -1 to -5.
- An alternative strong acidifier could be found in acidifying is performed by adding SO2(g) , organic acids, hydrochloric acid (HCI), nitric acid (HNO 3 ), hydroiodic acid (HI), hydrobromic acid (HBr) or perchloric acid (HCLO4), even if the alternatives with chlorides most often is less preferred due to environmental load.
- the fresh sulfuric acid added to the process could be obtained from so called "spent acid” from a chlorine dioxide generator or fresh sulfuric acid from a chemical supplier, or mixtures thereof.
- the present invention solves above problems, both the disposal problem of the odorous sodium sulfide as well as a reduced charge of acidifier in the first acidification stage.
- dewatering embraces any means of dewatering.
- the dewatering is performed by using centrifugation, a filter press apparatus, a band filter, a rotary filter, such as a drum filter, or a sedimentation tank, or similar equipment, most preferred a filter press apparatus is used.
- original black liquor embraces spent cooking liquor from a digester, having most of the lignin from the original cellulose material dissolved in the “original black liquor”.
- the “original black liquor” may also have a large content of organic and inorganic material, but other specific constituents, while keeping the bulk volume of dissolved lignin unaltered.
- the inventive method is related to separation of lignin from original black liquor comprising the following stages in sequence: a) Precipitation of lignin by a first acidification stage of the original black liquor by adding a first acid b) followed by dewatering while forming a first filter cake with high content of lignin, c) suspending the first lignin filter cake obtained in stage b in a second acidification stage using a second acid, d) whereupon a second lignin suspension is obtained, e) dewatering of the second lignin suspension forming a second filter cake with high content of lignin, f) washing the second filter cake and finally, g) dewatering of the washed second lignin cake obtaining a lignin product.
- the improvement according to the inventive process is that the waste gases emitted from the second acidification stage is re-circulated and mixed with the original black liquor at the latest in the first acidification stage.
- the waste gases emitted from the second acidification stage are treated in a conversion process wherein at least a part of the waste gas components is converted to a stronger acid having a lower pK a value before being re-circulated and mixed with the original black liquor.
- the conversion process preferably takes place in a combustion chamber wherein the combustion is assisted with air or oxygen supply.
- the waste gases emitted from the second acidification stage be collected by a pump that establish a sub atmospheric pressure during the second acidification stage in order to increase degassing and collection of all gases emitted and avoid leakage of odorous gases to the environment.
- the first acid a weak acid having a positive pK a , preferably carbon dioxide.
- the first acid is used in the total effective and yet environmental friendly acidifier that also do not add any dangerous chemicals into the liquor cycle is preferable. This would, however, not exclude the possibility of using the same acidifier as used as the second acid under the basic aspects of the invention.
- the second acid a strong acid having a negative pK a , preferably sulfuric acid.
- the amount of acidifier needed is dramatically reduced as the total volume of the lignin cake is less than 1/10 of the original black liquor volume. This would not exclude the possibility of using the same acidifier as used as the first acid under the basic aspects of the invention.
- the entire separation process from the first acidification stage and until obtaining the final lignin product, kept at acidic conditions below pH 6.
- the entire separation process from the first acidification stage is kept at acidic conditions even below pH 4.
- the pH level throughout the process is most preferred a pH from 1 to 3.5. This would prevent any separated lignin from being dissolved again, and the precipitated lignin would be subjected to repeat leaching of metals and other unwanted components, meeting the objectives of obtaining a clean lignin product at high yield.
- stage b) is at least the dewatering of stage b) but possibly also stage f) including blowing trough of the first, or second, filter cake by gas or a mixture of gases, preferably flue gases, air or vapor, most preferred air or overheated vapor, in order to dispose of the remaining black liquor.
- gases preferably flue gases, air or vapor, most preferred air or overheated vapor.
- This gas could also be re-circulated to the original black liquor if needed, as these gases may contain components that have a net contributing effect upon the acidification.
- the inventive method may also include the additional steps of combining the pH level adjustment with an adjustment of the ion strength, preferably by using alkali metal ions or alkaline earth metal ions, most preferred calcium ions.
- the inventive method may also include the additional steps of that at least a part of the filtrate from the dewatering in step g), or filtrate from washing in step T) is returned to the second acidification stage c) to further reduce the consumption of acid and water.
- Fig. 1 shows the prior art 2-stage lignin separation process according to WO 2006/031175.
- Fig. 2 shows the inventive modification of 2-stage lignin separation process.
- figure 1 is the known prior art process according to WO 2006/031175 shown.
- the separation of lignin from original black liquor BL comprising the following stages in sequence:
- FIG 2 is the inventive improvement of the prior art process according to WO 2006/031175 shown.
- the separation of lignin from original black liquor BL comprises the same basic steps as shown in figure 1 , but here the waste gases emitted from the second acidification stage, i.e. from reslurrying tank RT, is re-circulated and mixed with the original black liquor at the latest in the first acidification stage.
- the filtrate from the first dewatering stage in FP 1 is preferably re-circulated directly to a recovery system, preferably after re-alkalization.
- the gas used in FPi or WP for blowing through the filter cake is preferably air or flue gases, preferably flue gases from a recovery boiler, a bark boiler or a lime kiln.
- FIG 3 is an alternative embodiment of the inventive improvement of the prior art process according to WO 2006/031175 shown.
- the re-circulated gas from the reslurring stage in RT passed to an oxidization reactor where the gas is oxidized with or without a catalyst in a combustion process with a flame in an oxidation reactor OR, while being added with oxygen, O 2 .
- O 2 oxygen
- oxidization reactor could alternatively be a catalytic process or a combination of a combustion and a catalytic process similar to a sulfuric acid production process.
- the acidic strength of H 2 SO 3 and H 2 SO 4 corresponds to pK a values in the order of 1.8 and -3, respectively. If a large part of the H 2 S is converted to SO 2 and/or SO 3 , then the need for charging fresh carbon dioxide decreases even further in order to establish the low pH value for the lignin precipitation. The savings in charge of fresh carbon dioxide could then be reduced by some 10-20% further, depending upon the conversion efficiency in the oxidization and total amount of H 2 S preferably be collected by a vacuum pump P, pressurizing the gases and positively assuring that all emitted gases from the reslurrying tank is vented away.
- oxygen/air may be included in the stream of gases, due to slight sub atmospheric pressure in reslurrying tank, it would be advantageous to add the treated gases before charging the carbon dioxide to the original black liquor, i.e. in the in feed pipe to precipitation reactor PR as shown in figure, or any other suitable vessel.
- An additional procedure for stabilizing the lignin during the 2-stage process is, in combination with a pH-decrease, to adjust the ionic strength in the slurry stage, preferably with multivalent alkali metal ions or alkaline earth metal ions (e.g. calcium).
- a higher ionic strength in the suspension stage reduces the lignin yield losses.
- the ionic strength and pH of the wash water preferably essentially correspond to the conditions in the slurry stage to avoid gradients during the washing process. A higher ionic strength in the slurry and in the wash water gives a stable lignin and high lignin yield even at pH- values in the upper acidic range.
- the method according to the first aspect of the present invention may further be performed, as set out above, whereby first the lignin is precipitated with carbon dioxide or other suitable acids according to previously known methods.
- the suspension is then dewatered in some form of separation equipment (e.g. some form of filtration equipment, sedimentation tank, centrifugation etc).
- a filter press equipment where the filter cake can be pressed to a high dry content is preferable.
- air is preferably blown through the pressed filter cake in order to remove as much as possible of the remaining black liquor. In this way, the acid consumption and hydrogen sulfide formation in the subsequent re-slurry stage can be considerably reduced.
- the filter cake is reslurried in tank RT preferably equipped with a suitable stirring device and equipped with an exhaust to take care of the hydrogen sulfide formed as well as residual and formed carbon dioxide.
Abstract
Description
Claims
Priority Applications (6)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/SE2009/000291 WO2010143997A1 (en) | 2009-06-10 | 2009-06-10 | Method for precipitating lignin from black liquor by utilizing waste gases |
EP09845900.1A EP2440703B1 (en) | 2009-06-10 | 2009-06-10 | Method for precipitating lignin from black liquor by utilizing waste gases |
BRPI0924867A BRPI0924867B1 (en) | 2009-06-10 | 2009-06-10 | method for separating lignin from black liquor using waste gases |
CA2763447A CA2763447C (en) | 2009-06-10 | 2009-06-10 | Method for precipitating lignin from black liquor by utilizing waste gases |
US13/375,901 US9067959B2 (en) | 2009-06-10 | 2009-06-10 | Method for precipitating lignin from black liquor by utilizing waste gases |
ES09845900T ES2571977T3 (en) | 2009-06-10 | 2009-06-10 | Method for precipitating lignin from black liquor using waste gases |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/SE2009/000291 WO2010143997A1 (en) | 2009-06-10 | 2009-06-10 | Method for precipitating lignin from black liquor by utilizing waste gases |
Publications (1)
Publication Number | Publication Date |
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WO2010143997A1 true WO2010143997A1 (en) | 2010-12-16 |
Family
ID=43309066
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/SE2009/000291 WO2010143997A1 (en) | 2009-06-10 | 2009-06-10 | Method for precipitating lignin from black liquor by utilizing waste gases |
Country Status (6)
Country | Link |
---|---|
US (1) | US9067959B2 (en) |
EP (1) | EP2440703B1 (en) |
BR (1) | BRPI0924867B1 (en) |
CA (1) | CA2763447C (en) |
ES (1) | ES2571977T3 (en) |
WO (1) | WO2010143997A1 (en) |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2012161865A1 (en) | 2011-05-24 | 2012-11-29 | Liquid Lignin Company, Llc | Process for treating lignin |
WO2012177198A1 (en) * | 2011-06-22 | 2012-12-27 | Metso Power Ab | Method for lignin separation from black liquor comprising multiple acidification steps |
WO2013070130A1 (en) | 2011-11-11 | 2013-05-16 | Metso Power Ab | Method for lignin separation from black liquor involving multiple acidification steps |
WO2013137790A1 (en) * | 2012-03-16 | 2013-09-19 | Metso Power Ab | Method for lignin separation from black liquor |
WO2014118441A1 (en) | 2013-02-04 | 2014-08-07 | Andritz Oy | Method for recovering chemicals and by-products from high-sulphidity pulping liquors |
WO2015018944A1 (en) | 2013-08-09 | 2015-02-12 | Suncoal Industries Gmbh | Method for extracting lignin from black liquor and products produced thereby |
EP2726671A4 (en) * | 2011-06-28 | 2015-02-25 | Valmet Power Ab | Method for lignin separation from black liquor comprising removal of sulphur compounds from formed water effluent |
WO2018004447A1 (en) * | 2016-07-01 | 2018-01-04 | Ren Fuel K2B Ab | Ultrapure kraft lignin composition |
US10415184B2 (en) | 2014-08-08 | 2019-09-17 | Suncoal Industries Gmbh | Method for obtaining stabilized lignin having a defined particle-size distribution from a lignin-containing liquid |
WO2019241408A1 (en) * | 2018-06-12 | 2019-12-19 | Domtar Paper Company, Llc | Methods and processes for lignin isolation/extraction |
WO2019241413A1 (en) * | 2018-06-12 | 2019-12-19 | Domtar Paper Company, Llc | Methods and processes for lignin isolation/extraction |
WO2023277776A1 (en) * | 2021-06-30 | 2023-01-05 | Valmet Ab | Method and system for lignin production |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FI127010B (en) * | 2012-08-24 | 2017-09-29 | Upm Kymmene Corp | A method for recovering low molecular weight lignin from a filtrate |
SE539560C2 (en) * | 2015-03-06 | 2017-10-10 | Innventia Ab | Electrode active coating for a lithium-ion battery and method of production therefore |
CN105088847B (en) * | 2015-09-07 | 2018-02-13 | 武汉凯比思电力设备有限公司 | A kind of device and method that separating lignin is extracted by black liquid |
US11866456B2 (en) * | 2020-07-14 | 2024-01-09 | Liquid Lignin Company | Process for treating lignin |
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WO2006031175A1 (en) | 2004-09-14 | 2006-03-23 | Lignoboost Ab | Method for separating lignin from black liquor |
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CN101445522A (en) * | 2008-12-29 | 2009-06-03 | 邵国标 | Method for preparing modified kraft pulp sodium lignosulphonate |
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EP2247785B1 (en) * | 2008-02-21 | 2019-12-18 | Valmet AB | A method for separating lignin from black liquor, a lignin product, and use of a lignin product for the production of fuels or materials |
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2009
- 2009-06-10 WO PCT/SE2009/000291 patent/WO2010143997A1/en active Application Filing
- 2009-06-10 BR BRPI0924867A patent/BRPI0924867B1/en active IP Right Grant
- 2009-06-10 CA CA2763447A patent/CA2763447C/en active Active
- 2009-06-10 US US13/375,901 patent/US9067959B2/en not_active Expired - Fee Related
- 2009-06-10 EP EP09845900.1A patent/EP2440703B1/en active Active
- 2009-06-10 ES ES09845900T patent/ES2571977T3/en active Active
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WO2006031175A1 (en) | 2004-09-14 | 2006-03-23 | Lignoboost Ab | Method for separating lignin from black liquor |
US20080214796A1 (en) * | 2004-09-14 | 2008-09-04 | Per Tomani | Method |
WO2006038863A1 (en) | 2004-10-07 | 2006-04-13 | Lignoboost Ab | Method for separating lignin from a lignin containing liquid/slurry |
WO2008079072A1 (en) * | 2006-12-22 | 2008-07-03 | Kiram Ab | Method for recovering a low sodium content lignin fuel from black liquor |
CN101445522A (en) * | 2008-12-29 | 2009-06-03 | 邵国标 | Method for preparing modified kraft pulp sodium lignosulphonate |
Non-Patent Citations (1)
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Cited By (19)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2012161865A1 (en) | 2011-05-24 | 2012-11-29 | Liquid Lignin Company, Llc | Process for treating lignin |
EP3494256A4 (en) * | 2011-05-24 | 2020-03-18 | Liquid Lignin Company, LLC | Process for treating lignin |
WO2012177198A1 (en) * | 2011-06-22 | 2012-12-27 | Metso Power Ab | Method for lignin separation from black liquor comprising multiple acidification steps |
US9266917B2 (en) | 2011-06-22 | 2016-02-23 | Valmet Ab | Method for lignin separation from black liquor having multiple acidification steps |
EP2726671A4 (en) * | 2011-06-28 | 2015-02-25 | Valmet Power Ab | Method for lignin separation from black liquor comprising removal of sulphur compounds from formed water effluent |
WO2013070130A1 (en) | 2011-11-11 | 2013-05-16 | Metso Power Ab | Method for lignin separation from black liquor involving multiple acidification steps |
EP2776621A4 (en) * | 2011-11-11 | 2015-06-24 | Valmet Power Ab | Method for lignin separation from black liquor involving multiple acidification steps |
US9777033B2 (en) | 2012-03-16 | 2017-10-03 | Valmet Ab | Method for lignin separation from black liquor |
WO2013137790A1 (en) * | 2012-03-16 | 2013-09-19 | Metso Power Ab | Method for lignin separation from black liquor |
WO2014118441A1 (en) | 2013-02-04 | 2014-08-07 | Andritz Oy | Method for recovering chemicals and by-products from high-sulphidity pulping liquors |
US10011949B2 (en) | 2013-02-04 | 2018-07-03 | Andritz Oy | Method for recovering chemicals and by-products from high-sulphidity pulping liquors |
US9902816B2 (en) | 2013-08-09 | 2018-02-27 | Suncoal Industries Gmbh | Method for extracting lignin from black liquor and products produced thereby |
WO2015018944A1 (en) | 2013-08-09 | 2015-02-12 | Suncoal Industries Gmbh | Method for extracting lignin from black liquor and products produced thereby |
US10611885B2 (en) | 2013-08-09 | 2020-04-07 | Suncoal Industries Gmbh | Products extracted from black liquor |
US10415184B2 (en) | 2014-08-08 | 2019-09-17 | Suncoal Industries Gmbh | Method for obtaining stabilized lignin having a defined particle-size distribution from a lignin-containing liquid |
WO2018004447A1 (en) * | 2016-07-01 | 2018-01-04 | Ren Fuel K2B Ab | Ultrapure kraft lignin composition |
WO2019241408A1 (en) * | 2018-06-12 | 2019-12-19 | Domtar Paper Company, Llc | Methods and processes for lignin isolation/extraction |
WO2019241413A1 (en) * | 2018-06-12 | 2019-12-19 | Domtar Paper Company, Llc | Methods and processes for lignin isolation/extraction |
WO2023277776A1 (en) * | 2021-06-30 | 2023-01-05 | Valmet Ab | Method and system for lignin production |
Also Published As
Publication number | Publication date |
---|---|
EP2440703A4 (en) | 2014-01-22 |
CA2763447A1 (en) | 2010-12-16 |
BRPI0924867A2 (en) | 2016-04-26 |
US20140275498A1 (en) | 2014-09-18 |
US9067959B2 (en) | 2015-06-30 |
BRPI0924867B1 (en) | 2018-12-18 |
EP2440703B1 (en) | 2016-02-17 |
ES2571977T3 (en) | 2016-05-27 |
EP2440703A1 (en) | 2012-04-18 |
CA2763447C (en) | 2017-10-31 |
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