JPH01221589A - Method for caustifying green liquor - Google Patents
Method for caustifying green liquorInfo
- Publication number
- JPH01221589A JPH01221589A JP4498288A JP4498288A JPH01221589A JP H01221589 A JPH01221589 A JP H01221589A JP 4498288 A JP4498288 A JP 4498288A JP 4498288 A JP4498288 A JP 4498288A JP H01221589 A JPH01221589 A JP H01221589A
- Authority
- JP
- Japan
- Prior art keywords
- green liquor
- added
- quicklime
- stage
- quick lime
- 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.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 33
- ODINCKMPIJJUCX-UHFFFAOYSA-N Calcium oxide Chemical compound [Ca]=O ODINCKMPIJJUCX-UHFFFAOYSA-N 0.000 claims abstract description 66
- 239000000292 calcium oxide Substances 0.000 claims abstract description 33
- 235000012255 calcium oxide Nutrition 0.000 claims abstract description 33
- 239000010802 sludge Substances 0.000 claims abstract description 13
- 235000008733 Citrus aurantifolia Nutrition 0.000 claims abstract description 10
- 235000011941 Tilia x europaea Nutrition 0.000 claims abstract description 10
- 239000004571 lime Substances 0.000 claims abstract description 10
- 239000002655 kraft paper Substances 0.000 claims abstract description 5
- 238000009993 causticizing Methods 0.000 claims description 15
- 238000004519 manufacturing process Methods 0.000 claims description 8
- 239000003518 caustics Substances 0.000 claims description 7
- 238000005352 clarification Methods 0.000 abstract description 13
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 abstract description 12
- 235000011121 sodium hydroxide Nutrition 0.000 abstract description 4
- 239000000126 substance Substances 0.000 description 12
- 238000004062 sedimentation Methods 0.000 description 10
- 239000012535 impurity Substances 0.000 description 9
- 238000010411 cooking Methods 0.000 description 7
- 238000011084 recovery Methods 0.000 description 7
- AXCZMVOFGPJBDE-UHFFFAOYSA-L calcium dihydroxide Chemical compound [OH-].[OH-].[Ca+2] AXCZMVOFGPJBDE-UHFFFAOYSA-L 0.000 description 6
- 239000000920 calcium hydroxide Substances 0.000 description 6
- 235000011116 calcium hydroxide Nutrition 0.000 description 6
- 229910001861 calcium hydroxide Inorganic materials 0.000 description 6
- 239000000839 emulsion Substances 0.000 description 6
- QVQLCTNNEUAWMS-UHFFFAOYSA-N barium oxide Chemical compound [Ba]=O QVQLCTNNEUAWMS-UHFFFAOYSA-N 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 239000000203 mixture Substances 0.000 description 4
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 description 3
- 238000004458 analytical method Methods 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 239000013049 sediment Substances 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- UCKMPCXJQFINFW-UHFFFAOYSA-N Sulphide Chemical compound [S-2] UCKMPCXJQFINFW-UHFFFAOYSA-N 0.000 description 2
- 239000000395 magnesium oxide Substances 0.000 description 2
- CPLXHLVBOLITMK-UHFFFAOYSA-N magnesium oxide Inorganic materials [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 2
- AXZKOIWUVFPNLO-UHFFFAOYSA-N magnesium;oxygen(2-) Chemical compound [O-2].[Mg+2] AXZKOIWUVFPNLO-UHFFFAOYSA-N 0.000 description 2
- 239000000123 paper Substances 0.000 description 2
- 229920000642 polymer Polymers 0.000 description 2
- 239000002244 precipitate Substances 0.000 description 2
- 238000000926 separation method Methods 0.000 description 2
- BVKZGUZCCUSVTD-UHFFFAOYSA-L Carbonate Chemical compound [O-]C([O-])=O BVKZGUZCCUSVTD-UHFFFAOYSA-L 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 238000009835 boiling Methods 0.000 description 1
- 235000010216 calcium carbonate Nutrition 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000008394 flocculating agent Substances 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 150000002506 iron compounds Chemical class 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 239000006228 supernatant Substances 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
- 239000002023 wood Substances 0.000 description 1
Abstract
Description
【発明の詳細な説明】
「産業上の利用分野」
本発明は、クラフトパルプ（以下、ＫＰと称する）製造
工程の一環である薬品回収工程における新規な緑液苛性
比法に関し、特に段階的に生石灰を添加することによっ
て効率良く緑液の清澄化および苛性化する方法に関する
。[Detailed Description of the Invention] "Industrial Application Field" The present invention relates to a novel green liquor caustic ratio method in the chemical recovery process that is part of the kraft pulp (hereinafter referred to as KP) manufacturing process, and in particular, in a step-by-step process. This invention relates to a method for efficiently clarifying and causticizing green liquor by adding quicklime.
「従来技術」
従来、ＫＰ製造工程の一環である薬品回収工程における
緑液の苛性比法としては、予め緑液中に含まれる不純物
を分離・除去し緑液を清澄化させた後、消和、苛性化反
応を行なわしめるのが一般的である。``Prior art'' Conventionally, the caustic ratio method for green liquor in the chemical recovery process, which is a part of the KP manufacturing process, involves separating and removing impurities contained in the green liquor in advance, clarifying the green liquor, and then slaked it. Generally, a causticizing reaction is carried out.
此処に、緑液というのは、木材チップをクラフト蒸解（
蒸解薬品である苛性ソーダと硫化ソーダの混合液でチッ
プを煮ること）した後その蒸解廃液とできたパルプを分
離し、薬品回収をする過程で発生するものであり、主と
して炭酸ソーダと硫化ソーダを含有するが鉄化合物等の
不純物（通常、ドレッグ等と称している）を含んでいる
ためにその水溶液が（黒）緑色に着色している。なお、
苛性化反応とは緑液に生石灰を添加し、蒸解薬品の主成
分である苛性ソーダを生成する反応のことである。Here, the green liquor is made by craft cooking wood chips (
It is generated during the process of boiling chips in a mixture of caustic soda and soda sulfide, which are cooking chemicals, and then separating the resulting pulp from the cooking waste liquid and recovering the chemicals.It mainly contains soda carbonate and soda sulfide. However, the aqueous solution is colored green (black) because it contains impurities such as iron compounds (usually referred to as dregs). In addition,
The causticizing reaction is a reaction in which quicklime is added to green liquor to produce caustic soda, the main component of cooking chemicals.
通常、緑液の清澄化方法としては、主にタラリファイヤ
ー（沈降濃縮機）が使用されている。また、連続式フィ
ルターはドレソグによるフィルタ−の目詰まりが激しく
緑液の清澄化用としては実用的には殆ど使用されていな
い。いずれにしても、現状の緑液の苛性化部清澄度とし
ては満足のいくものではない。Normally, a tallifier (sedimentation concentrator) is mainly used to clarify green liquor. In addition, continuous filters are rarely used practically for clarification of green liquor because they are severely clogged with dresog. In any case, the clarity of the causticized portion of the current green liquor is not satisfactory.
「発明が解決しようとする課題」
緑液中のドレフグや不純物の分離・除去が十分に行われ
ていないと蒸解液となる白液中に不純物が多く混在し、
結果として白液の薬品濃度を低下させると共に、ライム
スラッジ中にもドレフグや不純物が混入することになる
。その為に、次工程におけるスラッジの沈降性、濾過性
を著しく低下させ、さらにキルン（焼成炉）等における
スラッジ焼成装置での能率低下、重油原単位の悪化、焼
成生石灰の純度低下及び苛性化工程全般の操業性の低下
等をもたらすことになる。従って、緑液中のドレフグは
可能な限り効率的に分離・除去がなされなければならな
い。従来、緑液中のドレフグの分離方法としては前述し
た如く主にタラリファイヤーが使用されている。この装
置は所謂重力を利用した自然沈降法であり、ＫＰの生産
規模の拡大に伴って設備が大型化し、且つドレッグの分
離効率も不充分となり易いために高価な高分子凝集剤等
の添加を余儀なくさせられているのが実情である。``Problem to be solved by the invention'' If the separation and removal of dorefugu and impurities in the green liquor is not done sufficiently, many impurities will be mixed in the white liquor that becomes the cooking liquor.
As a result, the concentration of chemicals in the white liquor is reduced, and the lime sludge is also contaminated with Dreyfus and other impurities. Therefore, the sedimentation and filterability of the sludge in the next process are significantly reduced, and the efficiency of the sludge baking equipment in kilns (burning furnaces) etc. is reduced, the fuel oil consumption rate is deteriorated, the purity of calcined quicklime is reduced, and the causticization process is reduced. This will lead to a decline in overall operability. Therefore, the dorefugu in the green liquor must be separated and removed as efficiently as possible. Conventionally, as a method for separating Dreyfufish from green liquor, the Talalifier has been mainly used as described above. This equipment uses the so-called natural sedimentation method that uses gravity, and as the scale of KP production expands, the equipment becomes larger and the separation efficiency of the dreg tends to be insufficient, so it is necessary to add expensive polymer flocculants, etc. The reality is that we are forced to do so.
上記の如き理由から、本発明者等は鋭意検討を重ねた結
果、簡便な操作と若干の付帯設備により極めて高効率の
緑液清澄化並びに苛性比法を工業的に可能にする方法を
見出し、遂に本発明を完成するに至った。For the reasons mentioned above, the inventors of the present invention have made extensive studies and have discovered a method that makes extremely highly efficient green liquor clarification and caustic ratio method possible industrially using simple operations and some incidental equipment. We have finally completed the present invention.
「課題を解決するための手段」
本発明は、クラフトパルプ製造工程で発生する緑液に生
石灰を添加して消和、苛性化する工程において、該生石
灰の添加を二段階に分け、第一段階で少量の生石灰を添
加し、発生するライムスラッジを除去後、残余の生石灰
を添加して苛性化反応を終結させることを特徴とする苛
性比法である。``Means for Solving the Problems'' The present invention involves dividing the addition of quicklime into two stages in the process of adding quicklime to slaked and causticizing green liquor generated in the kraft pulp manufacturing process. This caustic ratio method is characterized by adding a small amount of quicklime, removing the generated lime sludge, and then adding the remaining quicklime to terminate the causticizing reaction.
「作用」
本発明は、ＫＰ製造工程における薬品回収工程で発生す
る緑液に、第一段階として全体（所要）の生石灰（Ｃａ
ｂ）添加量の０．５〜５０％を先添加し苛性化反応を行
うと同時に緑液中のドレッグを反応で生じるライムスラ
ッジ（Ｃａ ＣＯ３を主成分とする）と共沈させること
によって分離・除去を行い緑液の清澄化を図り、第二段
階として清澄化した緑液に残余の生石灰を添加し苛性化
反応を終結させ、不純物の少ないライムスラッジを生成
させるもので、生石灰二段階添加を特徴とする緑液苛性
比法を提供するものである。"Function" The present invention is designed to remove the total (required) quicklime (Ca) from the green liquor generated in the chemical recovery process in the KP manufacturing process as a first step.
b) 0.5 to 50% of the added amount is added first and a causticizing reaction is carried out. At the same time, Dreg in the green liquor is separated and co-precipitated with lime sludge (mainly composed of CaCO3) produced in the reaction. In the second step, the remaining quicklime is added to the clarified green liquor to terminate the causticization reaction and produce lime sludge with few impurities. This paper provides a characteristic green liquor caustic ratio method.
即ち、第一段階の少量の生石灰添加によって、緑液の清
澄度は従来方式であるタラリファイヤー単独処理に比較
して著しく改善された。次に、第一段階の処理を終えて
清澄化させられた緑液に残余の生石灰を第二段階の反応
用として添加することによって、不純物の少ないライム
スラッジが生成し、結果として苛性化工程内で循環蓄積
する不純物量が減少し且つライムスラッジの沈降性、濾
過性が良好となり、白液の薬品濃度も向上する。That is, by adding a small amount of quicklime in the first stage, the clarity of the green liquor was significantly improved compared to the conventional treatment using a tallifier alone. Next, by adding the remaining quicklime to the clarified green liquor after the first stage treatment for the second stage reaction, a lime sludge with less impurities is produced, resulting in a lime sludge that can be used in the causticizing process. The amount of impurities circulating and accumulating is reduced, the lime sludge has good sedimentation and filtration properties, and the chemical concentration of the white liquor is also improved.
第一段階で添加する生石灰の量は、緑液の不純度によっ
ても左右されるものであるが、通常は生石灰添加総量の
０．５〜５０重量％、より好ましくは２．５〜１５重量
％の範囲である。即ち、第一段階での生石灰添加量が上
記のより好ましい範囲より多すぎても、少なすぎても、
より大幅な効果を期待できるものではない。The amount of quicklime added in the first stage depends on the impurity of the green liquor, but is usually 0.5 to 50% by weight, more preferably 2.5 to 15% by weight of the total amount of quicklime added. is within the range of That is, even if the amount of quicklime added in the first stage is more or less than the above-mentioned more preferable range,
It is not possible to expect a greater effect.
次に、本発明の方法では、第一段階の生石灰の添加方法
として三つの方法が考えられる。Next, in the method of the present invention, there are three possible methods for adding quicklime in the first stage.
第一の方法は、緑液クラリファイヤ−等の緑液清澄化設
備においてドレッグ沈降促進剤として生石灰を添加する
方法である。この方法により、緑液クラリファイヤ−又
は他の緑液清澄化設備でのドレッグ除去効率は著しく改
善される。緑液処理量が一定の場合には緑液クラリファ
イヤ−等の清澄化設備の小型化も可能となる。さらに、
沈降促進剤として高価な高分子凝集剤等を使用する場合
に比較して、回収工程内の生石灰を使用することは経済
面のメリットが大きい。The first method is to add quicklime as a dreg sedimentation accelerator in green liquor clarification equipment such as a green liquor clarifier. This method significantly improves the efficiency of dreg removal in a green liquor clarifier or other green liquor clarification equipment. When the amount of green liquor to be processed is constant, it is possible to downsize the clarification equipment such as a green liquor clarifier. moreover,
Compared to using an expensive polymer flocculant or the like as a sedimentation accelerator, using quicklime in the recovery process has a large economic advantage.
第二の方法は、緑液クラリファイヤ−等の緑液清澄化設
備の前に前段として、スレーカー及び苛性化槽を設置し
、沈降作用をタラリファイヤーで行わしめる方法である
。The second method is to install a slaker and a causticizing tank as an upstream stage in front of a green liquor clarification equipment such as a green liquor clarifier, and to perform the sedimentation action with a talarifier.
第三の方法は、第二の方法と丁度逆の方法で、緑液クラ
リファイヤ−等の緑液清澄化設備の後にスレーカー、苛
性化槽及び沈降槽を設置付加する方法である。The third method is exactly the opposite of the second method, and is a method in which a slaker, a causticizing tank, and a sedimentation tank are installed and added after the green liquor clarification equipment such as a green liquor clarifier.
本発明の方法は、既に述べた如く、前段階において少量
の生石灰を添加し、緑液中のドレソグを生成するライム
スラッジと共沈させ、緑液から分離・除去するものであ
るが、ドレッグの沈降促進剤としては生石灰に限定する
ものではなく、効率の良い酸化マグネシウムや酸化バリ
ウム等も勿論使用可能ではある。しかし、ＫＰ製造法に
おける薬品回収工程の一環として生成する生石灰をその
まま使用できること、付帯設備を必要としないこと等、
とりわけ酸化マグネシウムや酸化バリウムより安価であ
るため、生石灰が好ましく使用される。As already mentioned, in the method of the present invention, a small amount of quicklime is added in the preliminary step, and it is co-precipitated with the lime sludge that produces dresog in the green liquor, and is separated and removed from the green liquor. The sedimentation accelerator is not limited to quicklime, and of course highly efficient magnesium oxide, barium oxide, etc. can also be used. However, the quicklime produced as part of the chemical recovery process in the KP manufacturing method can be used as is, and additional equipment is not required.
In particular, quicklime is preferably used because it is cheaper than magnesium oxide or barium oxide.
また、本発明の特徴は第一段階において主として緑液の
清澄化、第二段階において本来の緑液の苛性化反応を行
わしめるところにある。従って、第二段階においては蒸
解薬品として使用される白液が効率良く製造されること
が重要な要件であるが、本発明の方法によって製造され
る白液は、従来の生石灰−括添加方式に比較して、清澄
度が高く且つ蒸解薬品として充分な苛性化率を有するも
のである。Further, the feature of the present invention is that the green liquor is mainly clarified in the first stage, and the original causticization reaction of the green liquor is carried out in the second stage. Therefore, in the second stage, it is important to efficiently produce the white liquor used as a cooking chemical. In comparison, it has a high degree of clarity and a sufficient causticizing rate as a cooking chemical.
上記のように、本発明の方法を適用することによって、
効率的な緑液の清澄化が可能となり、さらに薬品回収の
要である苛性化反応が極めて効率良く促進されることが
明らかとなった。As mentioned above, by applying the method of the present invention,
It has become clear that efficient clarification of green liquor is possible and that the causticization reaction, which is the key to drug recovery, is promoted extremely efficiently.
「実施例」
以下に実施例をあげて本発明をより具体的に説明するが
、勿論これらに限定するものではない。"Example" The present invention will be described in more detail with reference to Examples below, but the present invention is of course not limited to these.
尚、例中の部及び％は特に断らない限りそれぞれ重量部
及び重量％を示す。In addition, parts and % in the examples indicate parts by weight and % by weight, respectively, unless otherwise specified.
実施例Ｉ
ＫＰ製造工程の薬品回収工程で発生する生石灰１部を水
１部に溶解し、固形分濃度５０％の消石灰乳濁液を調製
した。次いで、下記表１の如き組成を有する緑液１００
０部に消石灰乳濁液１部を添加し、温度を８５℃に維持
し５分間苛性化反応を行い、続けて５分間静置した後、
沈降傾斜法により沈澱物を分離・除去した。得られた上
澄液９００部に第二段階として消石灰乳濁液１３６部を
添加し、８５℃に維持した状態で９０分間苛性化反応を
行った。さらに、第一段階と同様にして生じた沈降物を
分離・除去し白液を得た。Example I One part of quicklime generated in the chemical recovery step of the KP manufacturing process was dissolved in one part of water to prepare a slaked lime emulsion with a solid content concentration of 50%. Next, green liquor 100 having a composition as shown in Table 1 below is prepared.
1 part of slaked lime emulsion was added to 0 parts, the temperature was maintained at 85°C, causticization reaction was carried out for 5 minutes, and the mixture was allowed to stand still for 5 minutes.
The precipitate was separated and removed by the sedimentation gradient method. As a second step, 136 parts of slaked lime emulsion was added to 900 parts of the obtained supernatant liquid, and a causticizing reaction was carried out for 90 minutes while maintaining the temperature at 85°C. Furthermore, the resulting precipitate was separated and removed in the same manner as in the first stage to obtain a white liquor.
このときの緑液及び白液の組成分析を行い、さらに苛性
化率及びｓｓｌを測定し、結果を表２に示した。The composition of the green liquor and white liquor at this time was analyzed, and the causticization rate and ssl were also measured, and the results are shown in Table 2.
表１
なお、緑液及び白液の組成分析、苛性化率及びＳｓｌの
測定はスカンジナビア紙パルプ標準規格ＳＣＡ Ｎ −
Ｎ２：６３及び５ＣＡＮ−Ｗ６：７１に準拠して行った
。また１、第二段階における沈降物の白色度は米国紙バ
ルブ技術協会標準規格Ｔ６７２ｏｓ−７６に準じてタブ
レットを調製し、エルレホ白色度計にて測定を行った。Table 1 The compositional analysis of green liquor and white liquor, the causticization rate, and the measurement of Ssl are based on the Scandinavian Paper and Pulp Standard SCA N-
It was conducted in accordance with N2:63 and 5CAN-W6:71. In addition, 1. The whiteness of the sediment in the second stage was measured by preparing a tablet according to the American Paper Valve Technology Association standard T672os-76 and using an Ellejo whiteness meter.
実施例２〜７
実施例１と同様の消石灰乳濁液及び緑液を用いて、表２
に示すように第一段階、第二段階で添加する消石灰乳濁
液の量を変化させた以外は全て実施例１と同様の方法で
行い、それらの結果を表２に示した。Examples 2 to 7 Using the same slaked lime emulsion and green liquor as in Example 1, Table 2
The same procedure as in Example 1 was carried out except that the amounts of slaked lime emulsion added in the first and second stages were changed as shown in Table 2, and the results are shown in Table 2.
比較例１
実施例１と同様の緑液１０００部に、実施例１と同様の
方法で調製した消石灰乳濁液１３７部を分割せずに一括
添加し、８５℃に維持しながら９０分間苛性化反応を行
った。次いで、実施例１と同様にして一生した沈降物を
分離・除去し白液を得た。Comparative Example 1 To 1000 parts of the same green liquor as in Example 1, 137 parts of slaked lime emulsion prepared in the same manner as in Example 1 was added all at once without dividing, and causticized for 90 minutes while maintaining the temperature at 85°C. The reaction was carried out. Then, in the same manner as in Example 1, the accumulated sediment was separated and removed to obtain a white liquor.
なお、白液の組成分析、苛性化率、ＳＳ量及び沈降物の
白色度を実施例１と同様に測定し、それらの結果を表２
に示した。In addition, the compositional analysis of the white liquor, the causticization rate, the amount of SS, and the whiteness of the sediment were measured in the same manner as in Example 1, and the results are shown in Table 2.
It was shown to.
「効果」
表２から明らかなように、実施例では第二段階の緑液Ｓ
Ｓ量は処理前の緑液ＳＳ量２４０ｐｐｍ （表１参照）
から大幅に減少しその清澄効果が顕著に出ている。さら
に実施例第二段階の白液ＳＳＭは比較例１の白液ＳＳ量
よりかなり少ない。"Effect" As is clear from Table 2, in the example, the second stage of green liquid S
The amount of S is 240 ppm of green liquor SS before treatment (see Table 1)
The clarification effect has been significantly reduced since then. Further, the amount of white liquor SSM in the second stage of the example is considerably smaller than the amount of white liquor SS in Comparative Example 1.
また、実施例における白液苛性化率は比較例１の白液苛
性化率と同水準に達している。これらの結果から、本発
明による実施例において、特にその第一段階での緑液の
清澄効果が極めて優れており、しかも第二段階において
も清澄な白液が得られ苛性化反応も満足の出来るもので
あった。Further, the causticizing rate of white liquor in the examples reached the same level as the causticizing rate of white liquor in Comparative Example 1. From these results, in the examples according to the present invention, the clarification effect of the green liquor in the first stage was extremely excellent, and clear white liquor was obtained even in the second stage, and the causticization reaction was also satisfactory. It was something.
Claims (2)
を添加して消和、苛性化する工程において、該生石灰の
添加を二段階に分け、第一段階で少量の生石灰を添加し
、発生するライムスラッジを除去後、残余の生石灰を添
加して苛性化反応を終結させることを特徴とする苛性比
法。(1) In the process of adding quicklime to slaked and causticizing the green liquor generated in the kraft pulp manufacturing process, the addition of quicklime is divided into two stages, and in the first stage, a small amount of quicklime is added and the green liquor is generated. A caustic ratio method characterized in that after lime sludge is removed, residual quicklime is added to terminate the causticizing reaction.
〜５０％の範囲である請求項（１）記載の苛性比法。(2) The amount of quicklime added in the first stage is 0.5 of the total amount added.
The caustic ratio method according to claim 1, wherein the ratio is in the range of 50%.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4498288A JPH01221589A (en) | 1988-02-25 | 1988-02-25 | Method for caustifying green liquor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP4498288A JPH01221589A (en) | 1988-02-25 | 1988-02-25 | Method for caustifying green liquor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01221589A true JPH01221589A (en) | 1989-09-05 |
Family
ID=12706669
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP4498288A Pending JPH01221589A (en) | 1988-02-25 | 1988-02-25 | Method for caustifying green liquor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01221589A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005333069A (en) * | 2004-05-21 | 2005-12-02 | Stanley Electric Co Ltd | Manufacturing method of light emitting diode |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5557093A (en) * | 1978-08-30 | 1980-04-26 | Rosenblads Patenter Ab | Pulp producing method and apparatus |
-
1988
- 1988-02-25 JP JP4498288A patent/JPH01221589A/en active Pending
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5557093A (en) * | 1978-08-30 | 1980-04-26 | Rosenblads Patenter Ab | Pulp producing method and apparatus |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005333069A (en) * | 2004-05-21 | 2005-12-02 | Stanley Electric Co Ltd | Manufacturing method of light emitting diode |
| JP4529544B2 (en) * | 2004-05-21 | 2010-08-25 | スタンレー電気株式会社 | LED manufacturing method |
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