KR930004578A - How to improve the lignin removal selectivity of pulp during the process of removing lignin by high density oxygen - Google Patents

How to improve the lignin removal selectivity of pulp during the process of removing lignin by high density oxygen Download PDF

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KR930004578A
KR930004578A KR1019920014738A KR920014738A KR930004578A KR 930004578 A KR930004578 A KR 930004578A KR 1019920014738 A KR1019920014738 A KR 1019920014738A KR 920014738 A KR920014738 A KR 920014738A KR 930004578 A KR930004578 A KR 930004578A
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pulp
lignin
high density
density
amount
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KR950013196B1 (en
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씨. 죠세프 제임스
에이치. 매튜스 크리스토퍼
티.터레트 스튜어트
더블유. 이커스 스펜서
그릭스 브루스 에프
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원본미기재
유니온 캠프 페이턴트 홀딩, 인코오포레이티드
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    • 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
    • D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
    • D21C9/10—Bleaching ; Apparatus therefor
    • D21C9/1005—Pretreatment of the pulp, e.g. degassing the pulp
    • 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
    • D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
    • D21C9/10—Bleaching ; Apparatus therefor
    • D21C9/147—Bleaching ; Apparatus therefor with oxygen or its allotropic modifications
    • 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
    • D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
    • D21C9/02—Washing ; Displacing cooking or pulp-treating liquors contained in the pulp by fluids, e.g. wash water or other pulp-treating agents
    • 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
    • D21C9/00—After-treatment of cellulose pulp, e.g. of wood pulp, or cotton linters ; Treatment of dilute or dewatered pulp or process improvement taking place after obtaining the raw cellulosic material and not provided for elsewhere
    • D21C9/10—Bleaching ; Apparatus therefor

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  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Wood Science & Technology (AREA)
  • Paper (AREA)

Abstract

내용 없음.No content.

Description

고밀도하 산소에의해 리그닌을 제거하는 공정중 펄프의 리그닌 제거 선택도를 향상시키는 방법How to improve the lignin removal selectivity of pulp during the process of removing lignin by high density oxygen

본 내용은 요부공개 건이므로 전문내용을 수록하지 않았음Since this is an open matter, no full text was included.

제1도는 본 발명의 첫번째 실시태양에 대한 도면이다,1 is a diagram of a first embodiment of the present invention,

제2도는 본 발명의 두번째 실시태양에 대한 도면이다,2 is a diagram of a second embodiment of the present invention,

제3도는 본 발명에 따라 알칼리성 물질로 처리하고 산소로 리그닌을 제거시킨 연목펄프의 펄프점도와 K수치의 상호관계를 종래 기술가 비교하여 도시한 그래프이다.3 is a graph showing a comparison between the pulp viscosity and K-values of softwood pulp treated with an alkaline substance and lignin removed with oxygen according to the present invention.

Claims (22)

하기 단계들을 포함하는, 고밀도 산소에 의해 리그닌을 제거하는 공정중에 펄프의 리그닌 제거 선택도를 향상시키는 방법 : 최초 세척 가압시에 펄프의 밀도가 적어도 약18%가 되도록 펄프를 초기 세척하는 단계; 저밀도 펄프를 형성시키도록 세척된 페프의 밀도를 약 10중량%미만으로 감소시켜 처음량의 알칼리물질을 세척된 펄프에 부가하고, 저밀도 펄프를 알칼리 물질과 결합시켜 알칼리 물질을 세척된 펄프에 부착하고, 저밀도 펄프를알칼리 물질과 결합시켜 알칼리 물질이 펄프 전체에 균일하게 분포되도록 하며, 알칼리 물질을 포함한 펄프의 밀도를 적어도 약18중량%로 증가시켜 고밀도 펄프에 균일하게 분산된 처음량의 알칼리 물질을 그대로 유지시키는 한편 압축배출물을 제거하고 고밀도 펄프를 형성시키는 단계; 상당부분의 압축배출물을 알칼리무질 결합단게로 재순화 시키는 단계; 펄프의 오븐 건조 중량을 기준으로 적어도 약 0.8 내지 7중량%인 전체량(상기 처음량 포함)의 알칼리 물질을 고밀도 펄프에 제공하는 단계 :및 알칼리 물질 함유 고밀도 펄프를 산소에의해 리그닌을 제거하여 향상된 리그닌제거 선택도 및 산소에 의해 리그닌 제거된 펄프를 얻는 단계.A method of enhancing lignin removal selectivity of pulp during a process for removing lignin by high density oxygen, comprising: initial washing the pulp so that the density of the pulp is at least about 18% upon initial wash pressurization; To reduce the density of the washed pep to less than about 10% by weight to form a low density pulp, an initial amount of alkaline material is added to the washed pulp, and the low density pulp is combined with the alkaline material to attach the alkaline material to the washed pulp. By combining low density pulp with alkali material, alkali material is distributed evenly throughout the pulp, and the density of pulp including alkali material is increased to at least about 18% by weight to obtain the first amount of alkali material uniformly dispersed in high density pulp. Maintaining the intact while removing the compressed discharge and forming a high density pulp; Recycling a substantial portion of the compressed effluent to an alkali-free bonding step; Providing the high density pulp with a total amount of alkali material (including the initial amount) of at least about 0.8 to 7% by weight based on the oven dry weight of the pulp; and the high density pulp containing alkali material by oxygen removal of lignin Obtaining lignin-depleted selectivity and lignin-depleted pulp by oxygen. 제1항에 있어서, 거의 모든 압축배출물이 알칼리물질과의 결합단계로 재순환되는 방법.2. The process of claim 1 wherein almost all of the compressed discharge is recycled to a bonding step with alkali material. 제1항에 있어서, 모든 알칼리 저밀도 펄프에 부가하여 고밀도 펄프에 가해진 알칼리 물질의 전체량이 처음량과 동일하도록 하는 방법.The method of claim 1 wherein the total amount of alkali material applied to the high density pulp in addition to all alkali low density pulp is equal to the initial amount. 제1항에 있어서, 두번째량의 알칼리 물질을 고밀도 펄프에 부가하는 단계를 부가로 포함하며, 초기량과 두번째양의 합이 고밀도 펄프에 가해진 알칼리 물질의 전체량과 동일하도록 하는 방법.The method of claim 1, further comprising adding a second amount of alkaline material to the high density pulp, wherein the sum of the initial amount and the second amount is equal to the total amount of alkaline material applied to the high density pulp. 제1항에 있어서, 두번째 세척 가압시에 펄프의 밀도를 증가시키는 방법.The method of claim 1, wherein the density of the pulp is increased upon a second wash pressurization. 제1항에 있어서, 보유탱크내에 소정량의 압축배출물을 보유함으로써 상기 밀도증가 단계가 간헐적 또는 불연속적으로 작동되는 경우에 압축배출물을 계속적으로 알칼리성 물질 결합 단계로 직접 회수시키는 방법.A process according to claim 1, wherein by retaining a predetermined amount of compressed discharge in a holding tank, the compressed discharge is directly recovered directly into the alkaline material binding step when the density increasing step is operated intermittently or discontinuously. 제1항에 있어서, 산소에 의해 리그닌이 제거된 펄프를 세척하고, 이때 생성되는 세척수 유출물중 일부를 초기 펄프 세척 단계로 재순환 시키는 단계를 부가로 포함하는 방법.The method of claim 1, further comprising washing the pulp from which lignin has been removed by oxygen and recycling some of the resulting wash water effluent to an initial pulp wash step. 제1항에 있어서 상기 펄프가 소정량의 알칼리 물질과 결합되었을 때 약 5중량%이하의 저밀도를 갖는 방법.The method of claim 1 wherein said pulp has a low density of less than about 5 percent by weight when combined with a predetermined amount of alkaline material. 제1항에 있어서, 산소로 리그닌을 제거하기 전에 펄프의 밀도를 약 25 내지 35중량%로 증가시키는 방법.The method of claim 1, wherein the density of the pulp is increased to about 25 to 35 weight percent before removing lignin with oxygen. 제1항에 있어서, 산소로 리그닌을 제거하는 단계를 통해 펄프의 셀룰로오즈 성분은 크게 손상시키지 않고 고밀도 펄프의 K수치를 50%를 감소시킴으로써 리그닌 제거 선택도를 향상시키는 방법.The method of claim 1, wherein the step of removing lignin with oxygen results in a 50% reduction in the K value of the high density pulp without significantly damaging the cellulose component of the pulp. 제10항에 있어서 K수치가 리그닌 제거되기전 약 10 내지 26에서 리그닌이 제거된 후 약 5 내지 10으로 감소하는 방법.The method of claim 10, wherein the K value decreases from about 10 to 26 before lignin removal to about 5 to 10 after lignin removal. 제4항에 있어서, 펄프는 비표백된 연목 펄프이며 펄프에 부가된 알칼리 물질의 전체량은 약 1.5 내지 4중량%이고, 초기량과 두번째량은 각각은 약 0.75 내지 2중량%범위인 방법.The method of claim 4, wherein the pulp is unbleached softwood pulp and the total amount of alkali material added to the pulp is about 1.5 to 4 weight percent, and the initial and second amounts range from about 0.75 to 2 weight percent, respectively. 제4항에 있어서, 펄프는 비표백된 강목 펄프이며 펄프에 부가된 알칼리 물질의 전체량은 약 1 내지 3.8중량%이고, 초기량과 두번째량 각각은 약 0.5 내지 1.9중량%범위인 방법.The method of claim 4, wherein the pulp is unbleached wood pulp and the total amount of alkali material added to the pulp is about 1 to 3.8 weight percent, and the initial and second amounts each range from about 0.5 to 1.9 weight percent. 하기 단계들을 포함하는, 고밀도 산소에 의해 리그닌을 제거하는 공정중에 펄프의 리그닌 제거 선택도를 향상시키는 방법; 최초 세척 가압시에 펄프의 밀도가 적어도 약18%가 되도록 펄프를 초기 세척하는 단계; 저밀도 펄프를 형성시키도록 세척된 페프의 밀도를 약 10중량%미만으로 감소시켜 처음량의 알칼리물질을 세척된 펄프에 부가하고, 저밀도 펄프를 알카리 물질과 결합시켜 알칼리 물질을 세척된 펄프에 부착하고, 저밀도 펄프를알칼리 물질과 결합시켜 알칼리 물질이 펄프 전체에 균일하게 분포되도록 하며, 알칼리 물질을 포함한 펄프의 밀도를 적어도 약18중량%로 증가시켜 고밀도 펄프에 균일하게 분산된 처음량의 알칼리 물질을 그대로 유지시키는 한편 압축배출물을 제거하고 고밀도 펄프를 형성시키는 단계; 상당부분의 압축배출물을 알칼리무질 결합단게로 재순화 시키는 단계; 펄프의 오븐 건조 중량을 기준으로 적어도 약 0.8 내지 7중량%인 전체량(상기 처음량 포함)의 알칼리 물질을 고밀도 펄프에 제공하는 단계; 및 알칼리 물질 함유 고밀도 펄프를 산소에 의해 리그닌을 제거하여 향상된 리그닌제거 선택도 및 산소에 의해 리그닌 제거된 펄프를 얻는 단계.A method of enhancing lignin removal selectivity of pulp during a process of removing lignin by high density oxygen, comprising the following steps; Initial washing the pulp so that the density of the pulp is at least about 18% upon initial wash pressurization; To reduce the density of the washed pulp to less than about 10% by weight to form low density pulp, an initial amount of alkaline material was added to the washed pulp, and the low density pulp was combined with the alkaline material to attach the alkaline material to the washed pulp. By combining low density pulp with alkali material, alkali material is distributed evenly throughout the pulp, and the density of pulp including alkali material is increased to at least about 18% by weight to obtain the first amount of alkali material uniformly dispersed in high density pulp. Maintaining the intact while removing the compressed discharge and forming a high density pulp; Recycling a substantial portion of the compressed effluent to an alkali-free bonding step; Providing the high density pulp with a total amount of alkali material (including the initial amount) that is at least about 0.8 to 7 weight percent based on the oven dry weight of the pulp; And removing the lignin by alkaline material-containing high density pulp to obtain lignin removal selectivity and lignin-depleted pulp by oxygen. 제14항에 있어서, 모든 알칼리 물질을 상기 저밀도의 펄프에 부가하여 고밀도 펄프에 가해진 알칼리 물질의 전체량이 처음량과 동일하도록 하는 방법.15. The method of claim 14, wherein all alkali material is added to the low density pulp so that the total amount of alkali material applied to the high density pulp is equal to the initial amount. 제14항에 있어서, 상기 고밀도 펄프에 두번째량의 알카리물질을 부가하는 단계를 부가로 포함하며, 초기량과 두번째량의 합이 고밀도 펄프에 가해진 알칼리 물질의 전체량과 동일하도록 하는 방법.15. The method of claim 14, further comprising adding a second amount of alkaline material to the high density pulp, such that the sum of the initial amount and the second amount is equal to the total amount of alkaline material applied to the high density pulp. 제14항에 있어서, 보유탱크내에 소정량의 압축배출물을 유지시킴으로써 밀도 증가 단계가 간헐적 또는 불연속적으로 작동되는 경우에 압축배출물을 직접 알칼리물질 단계로 연속하여 회수하는 단계를 포함하는 방법.15. The method according to claim 14, comprising the step of continuously recovering the compressed discharge directly into the alkaline phase when the density increasing step is operated intermittently or discontinuously by maintaining a predetermined amount of compressed discharge in the holding tank. 제14항에 있어서, 산소에 의해 리그닌이 제거된 펄프를 세척하고, 이때 생성되는 세척수 유출물중 일부를 초기 펄프 세척 단계로 재순환 시키는 단계를 부가로 포함하는 방법.15. The method of claim 14, further comprising washing the pulp from which lignin has been removed by oxygen and recycling some of the resulting wash water effluent to an initial pulp wash step. 제16항에 있어서, 펄프는 비표백된 연목 펄프이며 펄프에 부가된 알칼리 물질의 전체량은 약 1.5 내지 4중량%이고, 처음량과 두번째량 각각은 약 0.75 내지 2중량%범위내인 방법.The method of claim 16, wherein the pulp is unbleached softwood pulp and the total amount of alkali material added to the pulp is about 1.5 to 4 weight percent, and the first and second amounts each range from about 0.75 to 2 weight percent. 제16항에 있어서, 펄프는 비표백된 강목 펄프이며 펄프에 부가된 알칼리 물질의 전체량은 약 1 내지 3.8중량%이고, 처음량과 두번째량 각각은 약 0.5 내지 1.9중량%범위내인 방법.The method of claim 16, wherein the pulp is unbleached wood pulp and the total amount of alkali material added to the pulp is about 1 to 3.8 weight percent, and the first and second amounts are each in the range of about 0.5 to 1.9 weight percent. 제14항에 있어서, 산소로 리그닌을 제거하는 단계를 통해 펄프의 셀룰로오즈 성분은 크게 손상시키지 않고 고밀도 펄프의 K수치를 50%이상 감소시킴으로써 리그닌 제거 선택도를 향상시키는 방법.15. The method of claim 14, wherein the step of removing lignin with oxygen reduces the K value of the high density pulp by at least 50% without significantly damaging the cellulose component of the pulp. 제14항에 있어서, K수치가 리그닌이 제거되기전 약 10 내지 26에서 리그닌이 제거된 후 약 5 내지 10으로 감소하는 방법.The method of claim 14, wherein the K value decreases from about 10 to 26 before lignin is removed to about 5 to 10 after lignin is removed. ※ 참고사항 : 최초출원 내용에 의하여 공개되는 것임.※ Note: This is to be disclosed by the original application.
KR1019920014738A 1991-08-14 1992-08-14 A process for obtaining enhanced delignification selectivity of pulp during a oxygen delignification process KR950013196B1 (en)

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US74822291A 1991-08-14 1991-08-14
US07/748,222 1991-08-14

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KR950013196B1 KR950013196B1 (en) 1995-10-25

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KR100538083B1 (en) * 1999-06-14 2005-12-22 프랙스에어 테크놀로지, 인코포레이티드 Oxygen delignification of lignocellulosic material

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US9932709B2 (en) 2013-03-15 2018-04-03 Ecolab Usa Inc. Processes and compositions for brightness improvement in paper production
FI20115754A0 (en) * 2011-03-22 2011-07-15 Andritz Oy Process and arrangement for the treatment of chemical pulp
WO2014122533A2 (en) * 2013-02-08 2014-08-14 Gp Cellulose Gmbh Softwood kraft fiber having an improved a-cellulose content and its use in the production of chemical cellulose products
US20180030651A1 (en) * 2016-07-27 2018-02-01 Ecolab USA, Inc. Method and compositions for oxygen delignification of chemical pulp

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EP0211945A4 (en) * 1985-02-14 1987-07-06 Edward Francis Elton Method and apparatus for alkaline delignification of lignocellulosic fibrous materials.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100538083B1 (en) * 1999-06-14 2005-12-22 프랙스에어 테크놀로지, 인코포레이티드 Oxygen delignification of lignocellulosic material

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EP0530881A1 (en) 1993-03-10
NO923163L (en) 1993-02-15
ZA926092B (en) 1993-03-02
BR9203170A (en) 1993-03-30
NO923163D0 (en) 1992-08-13
JPH0726350B2 (en) 1995-03-22
FI923585A0 (en) 1992-08-11
SE9202338L (en) 1993-02-15
FI923585A (en) 1993-02-15
AU647950B2 (en) 1994-03-31
KR950013196B1 (en) 1995-10-25
CN1070969A (en) 1993-04-14
SE9202338D0 (en) 1992-08-12
CA2075875A1 (en) 1993-02-15
AU2095492A (en) 1993-02-25

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