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WO2003066961A1 - A process of recovering alkali from black liquor of papermaking - Google Patents

A process of recovering alkali from black liquor of papermaking Download PDF

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Publication number
WO2003066961A1
WO2003066961A1 PCT/CN2002/000290 CN0200290W WO03066961A1 WO 2003066961 A1 WO2003066961 A1 WO 2003066961A1 CN 0200290 W CN0200290 W CN 0200290W WO 03066961 A1 WO03066961 A1 WO 03066961A1
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WIPO (PCT)
Prior art keywords
causticizing
lime
green
liquor
causticization
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PCT/CN2002/000290
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English (en)
French (fr)
Inventor
Tianzhao Ai
Xuezhi Dong
Dong Ai
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Application filed by Individual filed Critical Individual
Priority to AU2002250794A priority Critical patent/AU2002250794B2/en
Priority to CA002475610A priority patent/CA2475610C/en
Priority to EP02719627A priority patent/EP1482087B1/en
Priority to AT02719627T priority patent/ATE529567T1/de
Priority to US10/503,812 priority patent/US7291245B2/en
Publication of WO2003066961A1 publication Critical patent/WO2003066961A1/zh
Anticipated expiration legal-status Critical
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Classifications

    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01F—COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM, CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THE RARE-EARTH METALS
    • C01F11/00—Compounds of calcium, strontium, or barium
    • C01F11/18—Carbonates
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01D—COMPOUNDS OF ALKALI METALS, i.e. LITHIUM, SODIUM, POTASSIUM, RUBIDIUM, CAESIUM, OR FRANCIUM
    • C01D1/00—Oxides or hydroxides of sodium, potassium or alkali metals in general
    • C01D1/04—Hydroxides
    • C01D1/20—Preparation by reacting oxides or hydroxides with alkali metal salts
    • 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
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/61—Micrometer sized, i.e. from 1-100 micrometer
    • C—CHEMISTRY; METALLURGY
    • C01—INORGANIC CHEMISTRY
    • C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
    • C01P2004/00—Particle morphology
    • C01P2004/60—Particles characterised by their size
    • C01P2004/62—Submicrometer sized, i.e. from 0.1-1 micrometer
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00—Technologies relating to the processing of minerals
    • Y02P40/40—Production or processing of lime, e.g. limestone regeneration of lime in pulp and sugar mills
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S423/00—Chemistry of inorganic compounds
    • Y10S423/03—Papermaking liquor

Definitions

  • the invention relates to an improved new process for alkali recovery of papermaking black liquor, which is applicable to the pollution control of alkali making pulp (wood pulp and straw pulp), and is particularly suitable for the technology of alkali recovery process of papermaking black liquor by traditional combustion process. Makeover.
  • the invention patent CN1239166 applied by Ai Tianzhao discloses a new process for the recovery of green liquor from caustic soda, which avoids the production of waste residue and white mud, and it also produces ordinary precipitated calcium carbonate while recovering alkali.
  • the calcium carbonate particles it produces are relatively coarse and average.
  • the particle size is about 5 ⁇ ⁇ , which can only be used in some papermaking industries that require the use of coarser particles of calcium carbonate, but cannot meet the requirements of fine particle calcium carbonate for coated paper, neutral sizing papermaking, and other industries.
  • the technical problem to be solved by the present invention is the secondary pollution of white mud in the traditional papermaking black liquor alkali recovery process and the need for white mud recovery treatment, but it is not the recovery treatment of white mud in the traditional alkali recovery process.
  • the purpose of the present invention is to improve the key technology of the causticizing process in the traditional alkali recovery process, to provide a method that can not only fundamentally avoid the generation of waste residue (white mud), eliminate the need for white mud recovery treatment, but also recover alkali.
  • ⁇ 111 is an improved new process for the recovery of black liquor from papermaking, which is a series of precipitated calcium carbonate products with different particle sizes such as fine calcium carbonate, which can be used in different industries, without secondary pollution during the production process.
  • the invention not only has good environmental benefits, but also has considerable economic benefits.
  • the present invention conducts a lot of research work on the causes of white mud secondary pollution in the traditional alkali recovery process.
  • the main component of the waste residue (white mud) produced by the traditional alkali recovery process is CaC0 3 produced by causticization.
  • the reason why it cannot be used as CaC0 3 product is because it also contains impurities brought in by green liquor and lime and excess Ca0 that has not participated in the reaction.
  • the present invention is of the traditional chemical recovery process of causticization step was crucial technological improvements, the technical solutions adopted are:
  • the present invention adds a lime purification treatment process to separate the impurities therein in advance, so that the impurities in the lime do not enter the caustic reaction system at all, and it is impossible to mix in CaC0 3 in the caustic reaction.
  • the specific steps of this process are: digest the lime into lime milk in advance with water or fresh wash water, separate the coarse lime residue, and then sieve the lime milk through a 180-800 mesh (excluding 180 mesh) screen. Pre-screened fine lime milk for causticizing. The sieved fine lime slag is combined with coarse lime slag and blended into pulverized coal to be used as a mineralizer for the combustion of a coal-fired boiler.
  • the green liquor sent from the combustion section is simply clarified to remove part of the green mud, and then the lime is directly digested with the clarified upper green liquor.
  • the black solid impurities (commonly known as green slime) in the green liquor are in a colloidal state, the particles are very fine, and the sedimentation rate is very slow.
  • the clarified upper clear green liquor still contains a considerable amount of green slime. After they enter the caustic reaction system Not only directly affects the purity and whiteness of CaC0 3 produced by the causticizing reaction, but also makes the white liquor difficult to clarify, the white mud is difficult to filter and wash, and affects the normal operation of the overall alkali recovery system.
  • the hydroxides and sulfides in the colloidal state in the green slime are not only fine particles, but also have a positive charge on the surface. Because the same kind of charges repel each other, Difficult to gather and settle. Under the green mud belt
  • the physical property of electric charge and the main component of the green liquor are special medium conditions such as Na 2 CO 3.
  • the present invention uses Ca 2+ to purify the green liquor.
  • any substance that can provide sufficient Ca 2+ ions can be used as a green liquid purification treatment agent, which includes various soluble calcium salts (such as CaCl 2 , Ca (N0 3 ) 2 or the like), a solution, a suspension, or a solid of any one of Ca0, Ca (0H) 2 or a mixture thereof.
  • various soluble calcium salts such as CaCl 2 , Ca (N0 3 ) 2 or the like
  • a solution, a suspension, or a solid of any one of Ca0, Ca (0H) 2 or a mixture thereof such as CaCl 2 , Ca (N0 3 ) 2 or the like
  • a solution such as CaCl 2 , Ca (N0 3 ) 2 or the like
  • a solution such as CaCl 2 , Ca (N0 3 ) 2 or the like
  • a solution such as Ca0, Ca (0H) 2 or a mixture thereof.
  • the green liquor obtained by evaporating, burning and dissolving the black liquor is placed in a green liquor purification processor, and the green liquor purification treatment agent (at a temperature of 0 to 80 ° C (excluding 80 ° C)) is added while stirring. Its main active ingredient is Ca 2+ ).
  • the Ca 2+ ions in the purification treatment agent react with Na 2 C0 3 in the green liquor to generate CaC0 3 precipitates.
  • the new ecological & (0 3 precipitate has a large specific surface area and strong adsorption capacity, and preferentially adsorbs its structure according to the precipitation surface.
  • the adsorption rule of crystal ions is a large specific surface area and strong adsorption capacity, and preferentially adsorbs its structure according to the precipitation surface. The adsorption rule of crystal ions.
  • the CaC0 3 precipitation surface In a green liquid with a large amount of Na 2 C0 3 , the CaC0 3 precipitation surface must preferentially adsorb its crystal ions C0 3 2 —, so that the CaC0 3 precipitation surface has a negative charge. Due to the electrostatic attraction, The negatively charged CaC0 3 precipitates and the positively charged colloidal material (green slime) in the green liquor accumulates and settles quickly. During this aggregation process, other impurities such as unburned carbon particles with a small density and difficult to settle are also wrapped in. Aggregates are quickly settled down.
  • the new ecological CaC0 3 is a good co-precipitating agent, in addition to rapidly agglomerating with colloids in the green liquor, it can also make metal ions in the green liquor. Impurities in the form such as Fe 3+ , Fe 2+ , Al 3+, etc. are also co-precipitated.
  • the green liquid added with the purification treatment agent and fully stirred is transferred to a green liquid clarifier, and clarified for 3 to 10 minutes.
  • the solid can sink Completely, a clear and transparent green liquid is obtained. If you can stay in the clarifier for 36 hours, you can get almost colorless clear and transparent green liquid.
  • the solids obtained by filtering the green mud at the bottom of the clarifier (not Colloids) are combined with the solids filtered out by fine filtration, washed and dehydrated and then sent to a Portland cement plant for use as raw materials for cement production.
  • the amount of purification treatment agent this is an important issue. If the amount is too small, the amount of newly formed CaC0 3 precipitates is small, and the negative charge on the surface of the CaC0 3 precipitate is not enough to neutralize the positive charge of the colloid in the green liquor. This will affect the aggregation and sedimentation rate of the solids. On the other hand, if the amount is too large, after neutralizing the positive charge of the colloid, the surface of the CaC0 3 precipitation will still carry a partial negative charge, which will also affect the sedimentation rate.
  • the specific dosage should be determined according to the amount of colloidal substances in the green liquor.
  • the traditional alkali recovery process only one step of causticizing is performed. In order to increase the causticizing degree of sodium carbonate, excess lime is usually added. Therefore, the waste slag (white mud) discharged from this causticizing system necessarily contains excessive Ca0 that does not participate in the reaction. Because the traditional alkali recovery process usually uses green liquor to directly react with lime, in order to speed up the reaction speed, the causticizing reaction is performed at a higher temperature (usually above 90 ° C). According to the theory of precipitation formation, the higher the reaction temperature, the larger the particles that form the precipitate. Therefore, the CaC0 3 particles produced by the causticization reaction in the conventional alkali recovery process are relatively large.
  • the present invention through two steps of causticization, not only the degree of causticization of Na 2 C0 3 is increased, but CaO added to the reaction system completely participates in the reaction, and all are converted into CaC0 3 .
  • the present invention performs a causticizing reaction at 0 to 70 ° C (excluding 70).
  • the reaction speed is still relatively high at relatively low temperatures.
  • CaO in lime milk is 1-6 times the theoretical amount required for the chemical reaction.
  • the refined green liquor obtained after the purification treatment and the fine lime milk obtained after the purification treatment are placed in a causticizer, and the first step of causticization is performed under the conditions of 0 to 70 ⁇ (excluding 70 ⁇ ).
  • the causticization reaction is:
  • the caustic relationship of the amount of refined green liquor added during the causticization in this step is that the Na 2 C0 3 contained in the refined green liquor and the excess CaO contained in the solids isolated after the first causticization are not involved in the reaction.
  • the ratio of parts by weight is 106 n: 56, where n is 1 to 50.
  • the excess CaO that did not participate in the reaction in the solid matter can completely participate in the reaction and all be converted into CaC 0 3 .
  • solid-liquid separation is performed.
  • the separated solution contains a large amount of excess Na 2 C0 3 that has not participated in the reaction, so it needs to be returned for the first step of causticization.
  • the separated solid can be washed to obtain pure aqueous precipitated calcium carbonate.
  • the particle size of the precipitated calcium carbonate prepared by the present invention can be controlled by selecting different process conditions.
  • the sieve for sieving lime milk is more than 200 mesh, the causticizing temperature is lower than 70 ° C, and the total alkalinity of the causticizing solution (calculated as NaOH)> 80 g / L, the particles below 2 ⁇ m can be obtained.
  • the present invention not only fundamentally avoids the generation of waste residue (white mud), does not require a white mud recovery treatment process, can greatly reduce the equipment investment and energy consumption of alkali recovery, and also recovers alkali, compared with traditional
  • the process has produced another important chemical raw material necessary for papermaking-precipitated calcium carbonate.
  • a series of precipitated calcium carbonate products with different physical properties such as particle size can be produced by using different process conditions, including coated paper and precipitated calcium carbonate for neutral sizing papermaking, and the average particle size is less than 1 ⁇ ⁇ fine precipitated calcium carbonate and the like.
  • These calcium carbonates are of good quality and can be used directly in papermaking or sold as a commodity in other industries. Therefore, the present invention has very considerable economic benefits.
  • the present invention is to digest lime with water (or fresh wash water).
  • the lime residue does not contain alkali brought in by the green liquor.
  • the free alkali (calculated as CaO) is less than 0.1%, so, this In the invention, the alkali loss is small, and the yield of the recovered alkali is improved to a certain extent compared with the traditional process.
  • the colloidal substance in the green liquor does not enter the reaction system, and the influence of the colloidal substance on the causticizing system is eliminated, so that the causticizing reaction speeds up, The settling speed and water filtration performance of the solids after chemicalization are significantly improved, the white liquor is easy to clarify, and the precipitate is easy to filter and wash, which is conducive to the normal operation of the overall alkali recovery system, which is particularly important for straw pulp plants.
  • the carbonic acid produced by the present invention has a special crystal form and is more suitable for papermaking, which is an unexpected technical effect. Electron microscopy results of a plurality of calcium carbonate samples prepared by the present invention show that their crystal forms are both short rod-shaped with smooth ends. The application test of this calcium carbonate on the paper machine shows that its use effect is better than the spindle shape commonly used in the paper industry. This may be because the calcium carbonate is formed in a liquid phase reaction system with a uniform medium and easily controlled conditions. The cause of this crystal form and its application effects need to be further studied.
  • the present invention has good compatibility with the traditional alkali recovery process, and it only needs to perform technical transformation on its caustic chemical section, and the investment in technical transformation equipment is small, and the process is simple and easy to implement.
  • the refined green liquor and fine lime milk obtained after the purification treatment were placed in a causticizer at a reaction temperature of 68.
  • the first step of causticization is carried out under the condition that the total alkalinity of C and the causticizing solution (calculated as NaOH) is 82 g / L, and after the causticizing, the solid-liquid separation is performed by filtration.
  • the filtered white liquor (containing NaOH, Na 2 S) is sent to the paper cooking section for recycling.
  • the second step of causticizing is carried out under the conditions of a temperature of 68 ° C and a total causticity of the causticizing solution (calculated as NaOH) of 82 g / L.
  • the CaO reaction is completed, it is filtered, and the filtered solution is returned for the first step.
  • Caustic The filtered solids can be washed to obtain pure aqueous precipitated calcium carbonate. Part of the water-containing calcium carbonate was directly used as a coating paper filler for application tests. The effect was good. The other part of the water-containing calcium carbonate was dried to make a calcium carbonate product, and subjected to chemical analysis and particle size distribution measurement. The results are shown in Table 1. .
  • the fine green liquor obtained after the purification treatment in Example 1 and the fine lime milk obtained after the purification treatment in this embodiment are used. It was placed in a causticizer, and the first step of causticizing was carried out under the conditions of a reaction temperature of 38 ° C and a total causticity of the causticizing solution (as NaOH) of 102 g / L. White liquor after causticizing was filtered, the filtered (including Na0H, Na 2 S) supplied to the cooking station recycled paper.
  • the second step of causticizing was carried out under the conditions of a temperature of 38 ° C and a total causticity of the causticizing solution (calculated as NaOH) of 102 g / L. After the CaO reaction was completed, it was filtered. The filtered solution is returned for the first step of causticizing.
  • the filtered solids can be washed to obtain pure Water precipitates calcium carbonate.
  • the filtered solids are combined with the solids filtered by a fine filter, and the solids obtained after washing and dehydration are used as cement.
  • the lime milk is sieved with a 400-mesh sieve, and then subjected to two-step causticization at a reaction temperature of 46 ° C and a total causticity of the causticizing solution (calculated as NaOH) of 92 g / L.
  • Table 1 shows the results of calcium quality testing.
  • Example 1 Example 2
  • Example 3 Example 4
  • Example 4 and Example 5 show that the precipitated calcium carbonate prepared from wheat straw pulp and reed pulp black liquor has a higher content of hydrochloric acid insoluble matter.
  • the content of CaC0 3 is relatively low, and other indicators meet the standard.
  • the high content of hydrochloric acid insolubles is caused by the high silicon content in the black liquor.
  • the high silicon content makes the calcium carbonate particles difficult to agglomerate and improves the dispersibility. When used as a papermaking filler, its use effect is better.
  • Electron microscopy analysis results and application experiments on the precipitated calcium carbonate prepared in the above five examples show that the crystal shapes of the calcium carbonate prepared in the different examples are basically the same, and both are smooth short rods at both ends. This crystal form of calcium carbonate is used for papermaking. Filler application experiments show that its application effect is better than the spindle shape commonly used in the paper industry. It has less wear on the paper machine and is more suitable for use on high-speed paper machines.
  • the measurement results of the particle size distribution of the precipitated calcium carbonate prepared in the above examples show that the present invention can prepare a series of precipitated calcium carbonates with different particle sizes by using different process conditions, including fine precipitates with an average particle size of less than 1 ⁇ m Calcium carbonate.
  • the present invention Compared with the traditional alkali recovery process, the present invention not only fundamentally avoids the generation of waste residues, omits the process of treating white mud pollution, greatly reduces the equipment investment and energy consumption of alkali recovery, and also recovers alkali while recovering alkali.

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  • Inorganic Chemistry (AREA)
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  • Compounds Of Alkaline-Earth Elements, Aluminum Or Rare-Earth Metals (AREA)

Description

改进的造纸黑液碱回收新工艺 技术领域
本发明涉及一种改进的造纸黑液碱回收新工艺， 它适用于碱法 制浆（木浆和草浆） 造纸黑液的污染治理， 尤其适用于传统燃烧法 造纸黑液碱回收工艺的技术改造。
背景技术
造纸黑液的污染及其治理已是举世瞩目的问题。 目前， 国际上 通用的比较成熟的造纸黑液污染治理技术是燃烧法碱回收。 关于这 种碱回收技术， 在《最新碱法制浆技术》（ [美 ]E. W.马科隆， T. M. 格雷斯编， 曹邦威译， 中国轻工业出版社， 1998年 6月版） 中有详 细的叙述。 其工艺过程可概括为： 将黑液经蒸发、 燃烧、 溶解转化 成绿液， 再用过量石灰苛化， 从而制得碱液（俗称白液）。 这种方法 消除了黑液的污染， 也回收了黑液中的碱， 但在回收碱的同时却产 生了大量的碱性废渣一白泥， 构成了严重的二次污染。 目前， 木浆 厂是将白泥回烧成石灰循环使用。 这种方法， 投资大， 能耗高（回 烧 1吨石灰约需 250kg燃料油）， 经济价值小， 只是为消除白泥二次 污染不得已而为之。 对于草浆厂， 因白泥中硅含量高不能回烧， 只 得把白泥排入江河湖海或填埋。 长期以来， 世界上的许多专家、 学 者一直在致力研究简便易行的白泥回收处理技术， 特别是草浆白泥 的处理技术。 究其研究思路， 大家均是在研究怎样对传统碱回收工 艺中产生的白泥进行处理和利用， 却很少有人研究怎样从根本上避 免这种废渣（白泥） 的产生。
艾天召申请的发明专利 CN1239166公开的 It纸黑液碱回收绿 液苛化新工艺 可以避免废渣一白泥的产生， 而且在回收碱的同时 还生产出了普通沉淀碳酸钙。 但是， 由于该发明所采用的反应温度 较高以及其他工艺条件的限制， 它所生产的碳酸钙颗粒较粗， 平均 粒径在 5 μ ΐη左右， 只能用于需要使用较粗颗粒碳酸钙的部分造纸 业， 但不能满足涂布纸和中性施胶造纸以及其他工业对细颗粒碳酸 钙的要求。
随着时代的发展， 世界造纸工业以及其他工业对较细颗粒， 特 别是微细级（平均粒径小于 Ιμπι )碳酸钙的需求量急剧增加， 因此 研究微细或超细沉淀碳酸钙的生产方法已是当今世界碳酸钙行业的 热门研究课题之一。 但是人们的研究思路都是以碳化法生产碳酸钙 为基砒， 却从未有人研究怎样以造纸黑液碱回收中的苛化反应为基 础来生产微细碳酸钙。
发明内容
1. 本发明所要解决的技术问题及其目的
本发明所要解决的技术问题是传统的造纸黑液碱回收工艺中存 在的白泥二次污染及需要进行白泥回收处理的问题， 但不是对传统 碱回收工艺的白泥进行回收处理。 本发明的目的是通过对传统碱回 收工艺中苛化工序的关键性技术改进， 提供一种不仅能从根本上避 免废渣（白泥）的产生， 不需要进行白泥回收处理， 并且在回收碱的 同时， 还能通过选用不同的工艺条件， 直接生产出 2μπι以下粒径> 50%的涂布纸用碳酸钙、 2μπι 以下粒径> 90%的中性施胶造纸用碳酸 钙、 平均粒径< ^111的微细碳酸钙等粒径大小不同， 可供不同工业 使用的系列沉淀碳酸钙产品， 生产过程中无二次污染的改进的造纸 黑液碱回收新工艺。 本发明不仅具有良好的环境效益， 而且具有非 常可观的经济效益。
2. 本发明采用的技术方案
为了从根本上解决传统造纸黑液碱回收工艺中存在白泥二次污 染及需要白泥回收处理的问题， 本发明对传统碱回收工艺中白泥二 次污染的成因进行了大量的研究工作。 研究表明， 在传统碱回收工 艺产生的废渣（白泥） 中， 其主要成分就是苛化反应产生的 CaC03， 它之所以不能作为 CaC03产品使用，是因为其中还含有绿液和石灰带 入的杂质及未参与反应的过量 Ca0。 为了在回收碱的同时使苛化反 应产生的 CaC03直接成为产品，本发明对传统碱回收工艺的苛化工序 进行了关键性的技术改进， 所采用的技术方案是：
(1) 苛化反应前， 增设石灰净化处理过程
在传统碱回收工艺中， 是用绿液直接消化石灰， 这样， 石灰中 的杂质随 CaO—起全部进入了苛化反应体系， 虽然消化后通过提渣， 分离出了部分的粗石灰渣， 但石灰中的大量杂质仍混入了苛化反应 产生的 CaC03中， 从而直接影响 CaC03的纯度。 为了避免这种情况， 本发明在石灰与绿液混合之前， 增设了石灰净化处理过程， 预先分 离出其中的杂质， 使石灰中的杂质根本就不进入苛化反应体系， 也 就不可能混杂在苛化反应产生的 CaC03中。 该过程的具体步骤是： 预先用水或淡洗水将石灰消化成石灰乳， 分离出其中的粗石灰 渣， 再将石灰乳用 180 - 800目（不含 180目）的筛网过筛， 过筛后的 精细石灰乳备苛化用。 筛出的细石灰渣与粗石灰渣合并后摻入到煤 粉中， 用作燃煤锅炉燃烧的矿化剂。
(2) 苛化反应前， 增设绿液净化处理过程
在传统的碱回收工艺中， 对燃烧工段送来的绿液， 只经过简单 的澄清除去部分绿泥， 然后直接用澄清后的上层清绿液消化石灰。 由于绿液中的黑色固体杂质（俗称绿泥） 为胶体状态， 颗粒很细， 沉降速度很慢， 在澄清后的上层清绿液中仍含有相当量的绿泥， 它 们进入苛化反应体系后，不仅直接影响苛化反应产生 CaC03的纯度和 白度， 而且使白液不易澄清， 白泥不易过滤和洗涤， 影响整体碱回 收系统的正常运行。
本发明在对錶泥物理性质的研究中发现， 绿泥中以胶体状态存 在的氢氧化物和硫化物等不仅颗粒很细， 而且表面带正电荷， 因为 同种电荷互相排斥， 因此颗粒之间难以聚集和沉降。 根据绿泥带正 电荷这一物理性质和绿液的主要成分是 Na2C03这种特殊的介质条 件， 本发明用 Ca2+离子对绿液进行净化处理。 关于用作净化处理剂 的具体物质， 根据净化作用机理， 凡是能提供足量 Ca2+离子的物质 均可用作绿液净化处理剂， 其中包括含各种可溶性钙盐（如 CaCl2、 Ca (N03) 2等）、 Ca0、 Ca (0H)2之中的任一种或它们的混合物的溶液、 悬浮液或固体。 但是， 从经济角度和对后续工序的影响等多种因素 考虑， 以含 Ca (OH) 2的浆液或含 CaCl2的溶液或二者的混合物作绿液 净化处理剂为宜。 本发明进行绿液净化处理的具体步骤和作用机理 如下：
将由黑液经蒸发、 燃烧、 溶解后得到的绿液置于绿液净化处理 器中， 在 0 ~ 80°C (不含 80°C )的温度下， 边搅拌边加入绿液净化处 理剂 （其主要作用成分是 Ca2+离子）。 此时净化处理剂中的 Ca2+离子 与绿液中的 Na2C03发生反应生成 CaC03沉淀， 新生态的 &( 03沉淀比 表面积大， 吸附能力强， 根据沉淀表面优先吸附其构晶离子的吸附 规律， 在有大量 Na2C03存在的绿液中， CaC03沉淀表面必然优先吸附 其构晶离子 C03 2— ,从而使 CaC03沉淀表面带负电荷。因静电引力作用， 带负电荷的 CaC03沉淀与绿液中带正电荷的胶体物质（绿泥）互相 引迅速聚集和沉降。 在此聚集过程中， 密度 小不易沉降的未燃炭 粒等其他杂质也被裹进了聚集体中而被迅速沉降下来。 又因为新生 态的 CaC03是一种性能良好的共沉淀剂，它除了能与绿液中的胶体迅 速结聚之外，还能使绿液中以金属离子形式存在的杂质如 Fe3+、 Fe2+、 Al3+等也被共沉淀下来。将上述加入净化处理剂并充分搅拌后的绿液 转入绿液澄清器中， 澄清 3 ~ 10分钟， 固形物便可基本沉降完全， 得到清澈透明的绿液， 如能在澄清器中停留 3 6小时， 便可得几乎 近于无色的清澈透明的绿液。 将澄清后的上层清绿液再进行精细过 滤， 以彻底除去其中尚存的极少量固形物， 精细过滤后的精绿液置 于贮槽中备苛化用。将澄清器底部的绿泥经过滤后所得的固形物（不 再是胶体） 与精细过滤滤出的固形物合并， 经洗涤、 脱水后送至硅 酸盐水泥厂用作生产水泥的原料。
关于净化处理剂的用量， 这是一个重要的问题， 如果用量过少， 则新生成 CaC03沉淀量就少， CaC03沉淀表面所带负电荷不足以中和 绿液中胶体所带的正电荷， 从而影响固形物的聚集和沉降速度， 反 之， 如果用量过多， 中和胶体所带正电荷以后， CaC03沉淀表面仍带 有部分负电荷， 同样会影响沉降速度。 具体用量应根据绿液中胶体 物质的量确定， 当单独使用含 Ca (0H) 2的浆液（以 CaO计）作净化处 理剂时， 净化处理剂浆液中所含 CaO与绿液中所含 N¾C03的重量比 为： 0. 01 ~ 1： 106。
(3) 通过两步苛化， 在回收碱的同时， 直接生产出涂布和中性施 胶造纸用沉淀碳酸钙、 平均粒径小于 Ιμπι的微细沉淀碳酸钙等粒径 大小不同， 可供不同工业使用的系列沉淀碳酸甸产品
在传统的碱回收工艺中， 只进行一步苛化， 为了提高碳酸钠的 苛化度， 通常加入过量石灰。 因此， 在从这种苛化体系排出的废渣 (白泥） 中必然含有未参与反应的过量 Ca0。 又因为传统碱回收工 艺通常是用绿液直接与石灰反应， 为了加快反应速度， 则在较高的 温度下（通常在 90°C以上）进行苛化反应。 根据沉淀形成的理论， 反应温度越高， 生成沉淀的颗粒就越大。 因此， 传统碱回收工艺中 苛化反应产生的 CaC03的颗粒较大。
在本发明中， 通过两步苛化， 从而既提高 Na2C03的苛化度， 又 使加入到反应体系中的 CaO完全参加反应， 全部转变成 CaC03。 为了 得到细颗粒的 CaC03, 本发明在 0 ~ 70 °C (不含 70 )条件下进行苛 化反应。 在本发明中， 因为苛化用的石灰已预先净化处理成了精细 石灰乳， 所以在比较低的温度下仍有较高的反应速度。
本发明进行两步苛化的具体步骤如下：
按照石灰乳中 CaO为化学反应所需理论量的 1 ~ 1. 6倍的计量关 系， 将净化处理后所得的精绿液与净化处理后所得的精细石灰乳置 于苛化器中， 在 0 ~ 70η (不含 70Ο 的条件下进行第一步苛化， 苛化反应为：
Na2C03 + Ca (OH) 2 = 2NaOH + CaC03 i
在此步苛化中， 由于 CaO过量， 所以可保证 Na2C03有比较高的 苛化度。苛化后经过滤或离心等进行固液分离，分离出的碱溶液（俗 称白液)， 送至造纸的蒸煮工段循环使用。 在分离出的固形物中， 既 含苛化反应产生的 CaC03, 又含尚未参与反应的过量 CaO, 为了除去 其中的过量 CaO, 则在此固形物中再加入过量的精绿液， 在 0 ~ 70 °C (不含 70°C ) 的条件下进行第二步苛化。 此步苛化时加入精绿液 的量应符合的计量关系是，精绿液中所含 Na2C03与第一步苛化后分 离出的固形物中所含未参与反应的过量 CaO的重量份数之比为 106 n : 56, 其中 n值为 1 ~ 50。 在此步苛化中， 由于 Na2C03大量过量， 所以可使上述固形物中未参与反应的过量 CaO完全参加反应， 全部 转变成 CaC03。 待第二步苛化进行到 CaO完全转变成 CaC03后再进行 固液分离， 分离出的溶液中因含有大量未参与反应的过量 Na2C03， 故需返回用于第一步苛化， 分离出的固形物经过洗涤即可得到纯净 的含水沉淀碳酸钙。
本发明所制沉淀碳酸钙的粒径大小可以通过选用不同的工艺条 件进行控制， 石灰乳过筛所用筛网孔径越小， 苛化反应温度越低， 进行苛化反应时反应物浓度越大， 则所得 CaC03的粒径就越小。 当石 灰乳过筛用筛网在 200目以上， 苛化反应温度低于 70°C , 苛化液的 总碱度（以 NaOH计） > 80 g /L时， 即可得 2 μ m以下粒径 > 50%的 涂布纸用碳酸钙；当石灰乳过筛用筛网在 400目以上，苛化反应温度 低于 50°C , 苛化液总碱度（以 NaOH计） > 90 g /L时， 即可得 2 μ πι 以下粒径 > 90%的中性施胶造纸用沉淀碳酸钙；当石灰乳过筛用筛网 在 500 目以上， 苛化反应温度低于 40 °C , 苛化液的总碱度（以 NaOH 计） > 100 g /L时， 即可制得平均粒径小于 1 μ m的微细沉淀碳酸钙。
3- 本发明的有益效果
与传统的造纸黑液碱回收工艺相比， 本发明的有益效果如下：
(1) 本发明不仅从根本上避免了废渣（白泥）的产生， 不需要白 泥回收处理工序， 能使碱回收的设备投资和能耗大幅度降低， 而且 在回收碱的同时， 比传统工艺多生产出了造纸所必需的另一种重要 化工原料一沉淀碳酸钙。 在本发明中还可以通过选用不同的工艺条 件， 生产出粒径大小等物理性能不同的系列沉淀碳酸钙产品， 其中 包括涂布纸和中性施胶造纸用沉淀碳酸甸、平均粒径小于 1 μ πΐ的微 细沉淀碳酸钙等。 这些碳酸钙质量好， 既可直接用于造纸， 也可作 商品出售用于其他工业。 因此， 本发明具有非常可观的经济效益。
(2) 本发明是用水（或淡洗水）消化石灰， 石灰渣中不含绿液带 入的碱， 生产的碳酸钙中， 游离碱（以 CaO计） 小于 0. 1%, 所以， 本发明中碱损失很少， 回收碱的产量比传统工艺有一定的提高。
(3) 本发明中， 由于苛化前进行了绿液净化处理， 使绿液中的胶 体物质未进入反应体系， 消除了胶体物质对苛化系统的影响， 从而 使苛化反应速度加快， 苛化后固形物的沉降速度和滤水性能明显提 高， 白液易于澄清， 沉淀易于过滤和洗涤， 从而有利于整体碱回收 系统的正常运行，这一点对于草浆厂尤为重要。
(4) 本发明生产的碳酸 ， 具有特殊的晶形， 更适用于造纸， 这 是一项意想不到的技术效果。 本发明所制多个碳酸钙样品的电镜检 测结果表明， 它们的晶形均是一种两头圆滑的短棒状。 此碳酸钙在 纸机上的应用试验表明， 其使用效果比造纸工业常用的纺锤形还要 好。 这可能是因为这种碳酸钙是在介质均匀、 条件易于控制的液相 反应体系中形成的。 关于此种晶形的成因及其应用效果等还有待深 入研究。
(5) 在传统碱回收工艺中，除产生白泥外，还产生另外两种废渣， 一种是石灰渣， 因其中含绿液带入的绿泥而呈灰绿色， 不能进一步 利用， 另一种是胶状绿泥。 而在本发明中， 是用水或淡洗水消化石 灰， 石灰渣中不含绿液带入的杂质， 可以直接掺入煤粉中用作燃烧 的矿化剂。 在本发明的缘液净化处理过程中， 加入绿液净化剂后使 得从绿液中分离出来的固形物可直接用作生产水泥的原料。 因此， 本发明完全做到了物尽其用， 没有任何废物排放， 无二次污染， 具 有很好的环境效益。
(6) 本发明与传统的碱回收工艺具有很好的兼容性，只需对其苛 化工段加以技术改造即可， 而且技改设备投资小， 工艺简单易行。
4. 附图
说明书附图为本发明的工艺流程方框图。
5. 实施例
下面结合实施例进一步说明本发明的工艺过程。
实施例 1
从硫酸盐法木浆厂碱回收燃烧工段取含 Na2C03 636份（重量份 数）的绿液， 置于绿液净化处理器中， 加热至 78°C , 边搅拌边加入 含 CaO 3. 6份（重量份数） 的 Ca (0H) 2浆液， 充分搅拌后转入绿液 澄清器中澄清， 将澄清后的清绿液再经精细过滤机过滤， 以彻底除 去其中尚存的少量固形物， 精细过滤后的精绿液置于贮槽中备苛化 用。 将澄清器底部的泥浆进行过滤， 滤出的绿液并入清绿液中， 滤 出的固形物与精细过滤机滤出的固形物合并， 再经洗涤， 脱水后所 得固形物用作生产水泥的原料。
取含 CaO 200份（重量份数） 的石灰， 用水消化成石灰乳， 分 离出其中的粗石灰渣， 再将石灰乳用 200 目筛网过筛， 过筛后的精 细石灰乳备苛化用， 筛出的细石灰渣与粗石灰渣合并后掺入到煤粉 中， 用作燃煤锅炉燃烧的矿化剂。
按照石灰乳中 CaO的重量为化学反应所需理论量的 1. 03倍的计 量关系， 将净化处理后所得的精绿液和精细石灰乳置于苛化器中， 在反应温度为 68。C和苛化液总碱度（以 NaOH计）为 82 g /L的条件 下进行第一步苛化， 苛化后经过滤进行固液分离。 滤出的白液（含 NaOH, Na2S )送至造纸蒸煮工段循环使用。 在滤出的固形物中再加 入过量的精绿液（精绿液中所含 Na2C03的重量与固形物中未参与反 应的过量 CaO的重量之比为 30 χ106 : 56 ), 在反应温度为 68°C和苛 化液总碱度（以 NaOH计） 为 82 g /L的条件下进行第二步苛化， 待 CaO反应完全后再过滤， 滤出的溶液返回用于第一步苛化。 滤出的 固形物经洗涤即可得到纯净的含水沉淀碳酸钙。 将一部分含水碳酸 钙直接作为涂布纸填料进行应用试验， 使用效果良好， 将另一部分 含水碳酸钙经烘干等制成碳酸钙成品， 并进行化学分析和粒径分布 测定， 结果示于表 1。
实施例 2
取含 CaO 200份（重量份数） 的石灰， 用水消化成石灰乳， 分 离出其中的粗石灰渣， 再将石灰乳用 500 目的筛网过筛， 过筛后的 精细石灰乳备苛化用。 筛出的细石灰渣与粗石灰渣合并后， 摻入煤 粉中用作燃煤锅炉燃烧的矿化剂。
按照石灰乳中 CaO的重量为苛化反应所需理论量的 1. 5倍的计 量关系， 将实施例 1 中净化处理后所得的精绿液与本实施例中净化 处理后所得的精细石灰乳置于苛化器中， 在反应温度为 38°C和苛化 液总碱度（以 NaOH计）为 102 g /L的条件下进行第一步苛化。 苛化 后进行过滤， 过滤出的白液（含 Na0H、 Na2S )送至造紙蒸煮工段循 环使用。 在滤出的固形物中再加入过量的精绿液（精绿液中所含 N C03的重量与固形物中未参与反应的过量 CaO 的重量之比为 2 X 106 : 56 ), 在反应温度为 38 ， 苛化液总碱度（以 NaOH计） 为 102 g /L的条件下进行第二步苛化， 待 CaO反应完全后再过滤。 滤出的 溶液返回用于第一步苛化， 滤出的固形物经洗涤后即可得纯净的含 水沉淀碳酸钙。 将一部分含水碳酸钙直接作为中性施胶造纸填料进 行应用试验， 结果表明， 其使用效果很好。 将另一部分经烘干等制 成碳酸 成品后， 进行化学分析和粒径分布测定， 结果示于表 1。
实施例 3
从烧碱法蔗渣浆厂碱回收燃烧工段取绿液， 按照实施例 1进行 绿液的净化处理， 石灰净化时， 石灰乳用 600 目筛网过筛， 然后在 反应温度为 30°C , 苛化液总碱度（以 NaOH计） 为 106 g /L的条件 下进行两步苛化， 所得碳酸钙的质量检测结果示于表 1。
实施例 4
从硫酸盐法苇浆厂碱回收燃烧工段取含 N C03 318份（重量份 数） 的绿液置于绿液净化处理器中， 加热至 66°C， 边搅拌边加入含 CaCl2 2. 8份（重量份数）的净化剂溶液， 充分搅拌后转入绿液澄清 器中澄清， 将澄清后的清绿液再经精细过滤机过滤， 精细过滤后的 精绿液备苛化用。 将澄清器底部的泥浆进行过滤， 滤出的绿液并入 清绿液中， 滤出的固形物与精细过滤机过滤出的固形物合并， 再经 洗涤、 脱水后所得固形物用作生产水泥的原料。 石灰净化时， 石灰 乳用 400目筛网过筛， 然后在反应温度为 46°C , 苛化液总碱度（以 NaOH计） 为 92 g /L的条件下进行两步苛化， 所得碳酸钙的质量检 测结果示于表 1。
实施例 5
从烧碱 -蒽醌法麦草浆厂碱回收燃烧工段取绿液， 先按照实施 例 4所述的绿液净化处理方法和工艺条件进行绿液净化处理， 再按 照实施例 3所述的石灰净化方法进行石灰净化处理， 然后在反应温 度为 20°C，苛化液总碱度（以 NaOH计） 为 108g/L的条件下进行两 步苛化， 所得碳酸钙的质量检测结果示于表 1。 实施例所用工艺条件及所制沉淀碳酸钙的质量检测结果 工艺条件 实施例 1 实施例 2 实施例 3 实施例 4 实施例 5 及 木浆 木浆 蔗渣浆 苇浆 麦草浆 检测结果 硫酸盐法 硫酸盐法 烧碱法 硫酸盐法 烧碱蒽醌法 绿液净化剂 Ca(0H)2 Ca(0H)2 Ca(0H)2 CaCl2 CaCl2 石灰乳过筛筛网， (目） 200 500 600 400 600 反应温度， 'C 68 38 30 46 20 苛 化 液 总 碱 度
82 102 106 92 108
(NaOH)，g/L
CaC03，％ (干基） 98.21 98.18 98.56 90.35 88.60 沉降体积， mL/g 3.2 4.6 5.6 3.5 5.8 筛佘物（45μπι), % 0.02 0 0 0.01 0 盐酸不溶物， % 0.086 0.085 0.10 8.28 9.45 游离碱（CaO计）， % 0.052 0.056 0.082 0.083 0.091 铁， % 0.046 0..048 0.056 0.086 0.064 锰， ％ 0.0041 0.0042 0.0038 0.0036 0.0039 白度， ％ 92.2 92.6 96.3 91.8 92.6 平均粒径（μιη) 2.9 0.80 0.62 1.8 0.42 粒径 <2μπι, % 53.8 99.0 99.2 92.6 99.6 实施例 1、 实施例 2和实施例 3所制沉淀碳酸 的化学分析结 果表明， 由木浆黑液和蔗渣浆黑液所制得的沉淀碳酸钙不仅完全符 合中华人民共和国国家标准 GB4794 - 84规定的标准， 而且其沉降体 积远高于标准， 这说明其分散性好。
实施例 4和实施例 5所制沉淀碳酸甸的化学分柝结果表明， 由 麦草浆和苇浆黑液制得的沉淀碳酸钙， 其盐酸不溶物的含量较高， 相应地 CaC03的含量则较低， 其他指标均符合标准。 盐酸不溶物含量 高是因为黑液中硅含量高所引起的。 实验表明， 硅含量高， 使碳酸 钙粒子不易团聚， 分散性提高， 用作造纸填料时， 其使用效果更好。
对以上五个实施例所制沉淀碳酸钙进行的电镜分析结果和应用 实验表明， 不同实施例所制碳酸钙的晶形基本一致， 均为两端圆滑 的短棒状， 这种晶形的碳酸钙作为造纸填料的应用实验表明， 其应 用效果比造纸业常用的纺锤形还要好。 它对纸机的磨损小， 更适合 于在高速纸机上使用。
以上实施例所制沉淀碳酸钙的粒径分布测定结果表明， 本发明 可以根据需要通过选用不同工艺条件制出粒径大小不同的系列沉淀 碳酸钙， 其中包括平均粒径小于 Ι μ ιη的微细沉淀碳酸鈣。
与传统碱回收工艺相比， 本发明不仅从根本上避免了废渣的产 生， 省去了白泥污染治理工序， 使碱回收的设备投资和能耗大幅度 降低， 而且在回收碱的同时， 还直接生产出造纸所必需的另一种重 要化工原料一微细沉淀碳酸钙， 因此具有良好的环境效益和非常可 观的经济效益。

Claims

权 利 要 求
1. 一种改进的造纸黑液碱回收新工艺， 包括将黑液蒸发， 燃烧， 溶解得到绿液， 再用石灰苛化制得碱液， 俗称白液， 其特征在于对 苛化工序进行了关键性的技术改进， 改进后的苛化工序的工艺过程 为，
( 1 ) 苛化反应前增设石灰净化处理过程？ 其具体步骤是， 预先用水或淡洗水将石灰消化成石灰乳， 并分离出其中的粗石 灰渣， 再将石灰乳用 180 800目 （不含 180目）的筛网过筛， 过筛 后的精细石灰乳备苛化用， 筛出的细石灰渣与粗石灰渣合并后掺入 到煤粉中， 用作燃煤锅炉燃烧的矿化剂，
( 2 ) 苛化反应前增设绿液净化处理过程， 其具体步骤是， 将由黑液经蒸发， 燃烧， 溶解后得到的绿液置于绿液净化处理 器中，在 0 ~ 80°C (不含 80°C )的温度下加入绿液净化处理剂（其主要 作用成分是 Ca2+离子）， 将加入净化处理剂后的绿液澄清， 澄清后的 上层清绿液再经精细过滤， 以彻底除去其中尚存在的极少量的固形 物， 精细过滤后的精绿液置于贮槽中备苛化用，
( 3 ) 通过两步苛化， 在回收碱的同时， 直接生产出涂布和中 性施胶造纸用沉淀碳酸 ， 以及平均粒径小于 1 μ m的微细沉淀碳酸 钙等粒径大小不同，可供不同工业使用的系列沉淀碳酸钙产品， 其具 体步骤如下，
按照石灰乳中所含 CaO为化学反应所需理论量的 1 ~ 1. 6倍的计 量关系， 将净化处理后所得的精绿液和净化处理后所得的精细石灰 乳， 置于苛化器中， 在反应温度为 0 ~ 70°C (不含 70 ） 的条件下 进行第一步苛化， 苛化后进行固液分离， 分离出的碱溶液俗称白液， 送至造纸的蒸煮工段循环使用， 在分离出的固形物中再加入精绿液， 在反应温度为 0 ~ 70°C (不含 ) 的条件下进行第二步苛化， 此 步苛化时加入精绿液的量应符合的计量关系是,精绿液中所含 N C03 的重量与一步苛化后滤出固形物中所含未参与反应的过量 CaO的重 量之比为 106n: 56, 其中 n值为 1 ~ 50， 待第二步苛化进行到 CaO完 全转变成 CaC03后再进行固液分离，分离出的溶液返回用于第一步苛 化， 分离出的固形物经洗涤即可得到纯净的含水沉淀碳酸钙。
2. 如权利要求 1所述的改进的造纸黑液碱回收新工艺， 其特征 在于该工艺所制沉淀碳酸钙的粒径大小可以通过选用不同的工艺条 件进行控制， 石灰乳过筛所用筛网孔径越小， 苛化反应温度越低， 进行苛化反应时反应物浓度越大， 则所得碳酸钙的粒径就越小， 当 石灰乳过筛用筛网在 200目以上， 苛化反应温度低于 70"C , 苛化液 的总碱度（以 NaOH计）大于 80g/L时， 即可得 2 μ m以下粒径 > 50% 的涂布纸用碳酸甸， 当石灰乳过筛用筛网在 400 目以上， 苛化反应 温度低于 50" ，苛化液总碱度（以 NaOH计） 大于 90g/L时， 即可制 得 2 μ πι以下粒径> 90%的中性施胶造纸用沉淀碳酸钙， 当石灰乳过 筛用筛网在 500 目以上， 苛化反应温度低于 40 °C，苛化液的总碱度 (以 NaOH计 )大于 100g/L时， 即可制得平均粒径小于 1 μ m的微细 沉淀碳酸钙。
3. 造纸黑液碱回收绿液净化处理过程所用绿液净化处理剂， 是 指所有能提供 Ca2+离子的物质， 其中包括含各种可溶性钙盐， CaO, Ca (0H) 2之中的任一种或它们的混合物的溶液， 悬浮液和固体， 当单 独使用含 Ca (OH) 2 (以 CaO计）的浆液作绿液净化处理剂时， 绿液净 化处理剂中所含 CaO与绿液中所含 N C03的重量比为 0. 01 ~ 1： 106。
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