JPH1015923A - Manufacture of gypsum board of paper-manufacturing pulp sludge and gypsum board of paper-manufacturing pulp sludge - Google Patents
Manufacture of gypsum board of paper-manufacturing pulp sludge and gypsum board of paper-manufacturing pulp sludgeInfo
- Publication number
- JPH1015923A JPH1015923A JP21038796A JP21038796A JPH1015923A JP H1015923 A JPH1015923 A JP H1015923A JP 21038796 A JP21038796 A JP 21038796A JP 21038796 A JP21038796 A JP 21038796A JP H1015923 A JPH1015923 A JP H1015923A
- Authority
- JP
- Japan
- Prior art keywords
- gypsum
- pulp sludge
- gypsum board
- paper
- dihydrate
- 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.)
- Granted
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B28/00—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements
- C04B28/14—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing calcium sulfate cements
- C04B28/141—Compositions of mortars, concrete or artificial stone, containing inorganic binders or the reaction product of an inorganic and an organic binder, e.g. polycarboxylate cements containing calcium sulfate cements containing dihydrated gypsum before the final hardening step, e.g. forming a dihydrated gypsum product followed by a de- and rehydration step
-
- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
- C04B2111/00—Mortars, concrete or artificial stone or mixtures to prepare them, characterised by specific function, property or use
- C04B2111/00474—Uses not provided for elsewhere in C04B2111/00
- C04B2111/00612—Uses not provided for elsewhere in C04B2111/00 as one or more layers of a layered structure
- C04B2111/0062—Gypsum-paper board like materials
-
- 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
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/91—Use of waste materials as fillers for mortars or concrete
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Ceramic Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Press-Shaping Or Shaping Using Conveyers (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、製紙工場の産業廃棄物
として焼却あるいは、埋め立てにより廃棄処分されてい
た製紙パルプスラッジを再活用して得る高強度の製紙パ
ルプスラッジ石膏ボードの製造方法および製紙パルプス
ラッジ石膏ボードに関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a high-strength paper pulp sludge gypsum board obtained by recycling paper pulp sludge that has been incinerated or landfilled as industrial waste in a paper mill and papermaking. Related to pulp sludge gypsum board.
【０００２】[0002]
【従来技術】製紙パルプスラッジは製紙工場の産業廃棄
物として大量に焼却あるいは、埋め立てにより廃棄処分
されており、その再利用方法として、建材用内・外装用
ボードとして再生することが提案されている。2. Description of the Related Art Paper pulp sludge has been incinerated in large quantities as industrial waste in paper mills or disposed of by landfill, and as a method of reusing it, it has been proposed to recycle it as internal / external boards for building materials. .
【０００３】その一利用方法として、製紙パルプスラッ
ジと半水石膏（ＣａＳＯ４・１／２Ｈ２Ｏ）を混練して
作られる建材用石膏ボードがある。ここで主原料として
使用される石膏は、天然に産出される天然石膏と合成さ
れた副産石膏とに大別される。いすれも二水石膏（Ｃａ
ＳＯ４・２Ｈ２Ｏ）で、これを焼いて半水石膏化する
か、加圧水溶液法で半水石膏化することにより製造され
る。前者はβ型石膏、後者はα型石膏と称されている。
建材用石膏ボードに用いられる原料用石膏は、焼成炉で
１５０〜１８０℃付近で焼くβ型石膏が主体である。[0003] As one use method, there is a gypsum board for building materials made by kneading papermaking pulp sludge and hemihydrate gypsum (CaSO41 / 2H2O). The gypsum used as a main raw material here is roughly classified into natural gypsum produced naturally and by-product gypsum synthesized. Anyway, dihydrate gypsum (Ca
(SO4.2H2O), and it is manufactured by baking it into gypsum hemihydrate, or gypsum hemihydrate by the pressurized aqueous solution method. The former is called β-type gypsum, and the latter is called α-type gypsum.
Gypsum for raw materials used for gypsum board for building materials is mainly β-type gypsum which is baked at around 150 to 180 ° C. in a firing furnace.
【０００４】製紙パルプスラッジを用いた石膏ボードの
製造方法としては、主原料に半水石膏を用い、強化剤と
してパルプ製紙廃泥と合成繊維、ガラス繊維などの長繊
維を添加し混合、加圧成型する建材用石膏ボードの製造
方法が提案されている。（特開昭５０−９５３２２号公
報参照）[0004] A method for producing a gypsum board using papermaking pulp sludge is to use gypsum hemihydrate as a main raw material, add pulpmaking waste mud as a reinforcing agent, and add long fibers such as synthetic fibers and glass fibers, mix and pressurize. A method for producing a gypsum board for a building material to be molded has been proposed. (See JP-A-50-95322)
【０００５】[0005]
【発明が解決しようとする課題】従来、建材用石膏ボー
ドの主原料である焼石膏（半水石膏）は、原料石膏→ド
ライヤー→焼成炉→粉砕機→サイロの多重工程を経て作
られる。このようにして作られた半水石膏は水と接触す
ると同時に水和反応が進行するため、凝結調整剤を用い
て水和時間を調整するなどし、建材用石膏ボードの主原
料として用いられている。特開昭５０−９５３２２号公
報では、前述した方法により製造された焼石膏を主原料
として用い、強化材としてパルプ製紙廃泥と合成繊維、
ガラス繊維などの長繊維を添加し、これにより強度向上
を図ることを基本とするものである。Conventionally, calcined gypsum (hemihydrate gypsum), which is the main raw material of gypsum board for building materials, is produced through multiple steps of raw gypsum → dryer → firing furnace → pulverizer → silo. The hemihydrate gypsum made in this way is in contact with water and at the same time the hydration reaction proceeds, so it is used as a main raw material for gypsum board for building materials, such as adjusting the hydration time using a setting regulator. I have. Japanese Patent Application Laid-Open No. 50-95322 discloses that calcined gypsum produced by the above-described method is used as a main raw material, and pulp paper waste mud and synthetic fibers are used as reinforcing materials.
Basically, long fibers such as glass fibers are added to improve strength.
【０００６】このように従来の建材用石膏ボードの製造
方法では、主原料の半水石膏の水和による硬化性に依存
するため、直接二水石膏を用いて建材用ボードを製造す
ることを退け、わざわざ工程の重なる二水石膏の焼成工
程を経て半水石膏を得ている。さらに、半水石膏は水和
の進行が早いので、水を添加する混合混練工程で、機材
へ付着した石膏が固着固化するという本質的な問題を有
している。As described above, the conventional method for manufacturing a gypsum board for building materials refuses to directly manufacture gypsum board using dihydrate gypsum because it depends on the hardening property of hydrated hemihydrate gypsum as a main raw material. A hemihydrate gypsum is obtained through a dihydrate gypsum baking step that is bothersome. Furthermore, since hemihydrate gypsum rapidly progresses in hydration, there is an essential problem that gypsum adhering to equipment is fixed and solidified in the mixing and kneading step of adding water.
【０００７】[0007]
【課題を解決するための手段】本発明は、二水石膏を主
原料とし、強化材に製紙パルプスラッジを添加し半乾式
混合したのち、圧縮成型中に温度１２０〜１５０℃、圧
力５〜２０ｋｇ／ｃｍ２下で一定時間保持し、その後放
圧放冷して二水石膏が半水石膏化した成型枠をそのまま
加水処理し、これを成型固化することを特徴とする製紙
パルプスラッジ石膏ボードの製造方法であり、それによ
り製造される製紙パルプスラッジ石膏ボードである。According to the present invention, gypsum is used as a main raw material, and papermaking pulp sludge is added to a reinforcing material and mixed in a semi-dry manner. Then, during compression molding, the temperature is 120 to 150 ° C. and the pressure is 5 to 20 kg. / Cm 2 for a certain period of time, and then depressurized and cooled to form a water-treated gypsum in which gypsum dihydrate is converted to hemihydrate gypsum, and then solidify this to form a paper pulp sludge gypsum board. It is a production method, and a papermaking pulp sludge gypsum board produced thereby.
【０００８】また、主原料である二水石膏に製紙パルプ
スラッジを添加し半乾式混合して圧縮成型後、温度１２
０〜１５０℃、圧力５〜２０ｋｇ／ｃｍ２下で一定時間
保持し、その後放圧放冷して二水石膏が半水石膏化した
成型枠をそのまま加水処理し、成型固化することを特徴
とする製紙パルプスラッジ石膏ボードの製造方法と、そ
れにより製造される製紙パルプスラッジ石膏ボードであ
る。Further, papermaking pulp sludge is added to gypsum gypsum, which is a main raw material, mixed in a semi-dry manner and compression-molded.
It is characterized in that it is kept at 0 to 150 ° C. under a pressure of 5 to 20 kg / cm 2 for a certain period of time, then depressurized and allowed to cool, and the molding frame in which gypsum dihydrate is converted into hemihydrate gypsum is directly treated and solidified by molding. A method for producing a papermaking pulp sludge gypsum board, and a papermaking pulp sludge gypsum board produced thereby.
【０００９】すなわち、本発明は高強度の建材用の製紙
パルプスラッジ石膏ボードの製造にあたり二水石膏を主
原料とし、圧縮成型中もしくはその後に加温加圧して型
枠の中で半水石膏化せしめ、これを再び加水処理して二
水石膏とし、固化することで従来技術のような半水石膏
化せしめる多重の焼成工程を省略することができ、併せ
て、水と半水石膏の水和によって起きる混合混練工程で
の機材への固着固化の排除を可能とした画期的な製紙パ
ルプスラッジ石膏ボードの製造方法を提供するものであ
る。That is, in the present invention, dihydrate gypsum is used as a main material in the production of paper pulp sludge gypsum board for high-strength building materials, and is heated and pressurized during or after compression molding to form hemihydrate gypsum in a mold. It is possible to omit the multiple firing steps of making the gypsum into a hemihydrate gypsum as in the prior art by solidifying the gypsum to form a dihydrate gypsum by rehydration, and also hydrating the gypsum with water. The present invention provides an epoch-making method for producing a paper pulp sludge gypsum board, which makes it possible to eliminate sticking and solidification to equipment in a mixing and kneading process caused by the above.
【００１０】[0010]
【作用】本発明における製紙パルプスラッジ中の含水微
細繊維と混合された二水石膏は、圧縮成型枠の中で温度
１２０〜１５０℃、圧力５〜２０ｋｇ／ｃｍ２のもとで
３〜１５分保持すると、半水石膏となる。かくして、加
温、加圧処理されてできた成型枠の半水石膏、もしくは
成型後に加温、加圧処理されてできた半水石膏は、加水
処理を施すことにより二水石膏となる。すなわち、二水
石膏→半水石膏→復水石膏化を成型枠の中で完結しうる
ものである。上記したように本発明の半水石膏処理は、
加温加圧した成型枠の中、もしくは成型後加温加圧する
ことにより達成できることを特徴としている。加温加圧
には相関があり、温度１１０℃以下では圧力２０ｋｇ／
ｃｍ２で長時間処理しても半水石膏化は難しい。加温加
圧は高温高圧下になるに従い、短時間で半水石膏と化す
が、好ましい範囲は１２０〜１５０℃、圧力５〜２０ｋ
ｇ／ｃｍ２で処理時間１５分である。本発明により処理
された半水石膏は、製紙パルプスラッジ中の微細繊維と
混合されたままの状態であり、加水処理の際この微細繊
維の毛細管を通じ半水石膏のそば迄湿潤加水されるの
で、微細繊維の極近傍から二水石膏の結晶が成長する。
そのため微細繊維と復水石膏との絡合性が強まり、高い
強度を有する製紙パルプスラッジ石膏ボードとなる。以
下具体的に実施例について説明する。The gypsum dihydrate mixed with the water-containing fine fibers in the papermaking pulp sludge of the present invention is heated for 3 to 15 minutes at a temperature of 120 to 150 ° C. and a pressure of 5 to 20 kg / cm 2 in a compression molding frame. When held, it becomes hemihydrate gypsum. Thus, the hemihydrate gypsum in the molding frame that has been heated and pressurized, or the hemihydrate gypsum that has been heated and pressurized after molding, becomes dihydrate gypsum by performing a water treatment. That is, the conversion from gypsum to gypsum hemihydrate to gypsum condensate can be completed in a molding frame. As described above, the hemihydrate gypsum treatment of the present invention comprises:
It can be achieved by heating and pressurizing in a heated and pressurized molding frame or by heating and pressurizing after molding. There is a correlation between heating and pressurization.
It is difficult to make hemihydrate gypsum even if it is treated for a long time at cm 2 . The heating and pressurization becomes hemihydrate gypsum in a short time as the temperature and pressure become high, and the preferable range is 120 to 150 ° C. and the pressure is 5 to 20 k.
g / cm 2 and treatment time is 15 minutes. The hemihydrate gypsum treated according to the present invention remains mixed with the fine fibers in the papermaking pulp sludge and is wet-hydrated through the capillary of the fine fibers to the vicinity of the gypsum during the water treatment. Gypsum dihydrate crystals grow from the very vicinity of the fine fibers.
Therefore, the entanglement between the fine fibers and the condensed gypsum is enhanced, and a paper pulp sludge gypsum board having high strength is obtained. Hereinafter, specific examples will be described.
【００１１】[0011]
【実施例１】水分５０％程度含有している製紙パルプス
ラッジと原料二水石膏を１：１で水分添加をしない半乾
式で混練混合し、圧縮成型中に温度１４０℃、圧力１０
ｋｇ／ｃｍ２下で１５分間保持し、その後放圧放冷して
二水石膏が半水石膏化した成型枠をそのまま加水処理し
た。得られた厚さ１２ｍｍ、縦３００ｍｍ、横３００ｍ
ｍの製紙パルプスラッジ石膏ボードにて、かさ比重、曲
げ強さ、圧縮強さの試験を行った。かさ比重１．２０、
曲げ強さ８０ｋｇｆ／ｃｍ２、圧縮強さ２５０ｋｇｆ／
ｃｍ２であった。曲げ強さはＪＩＳ Ａ１４０８、圧縮
強さはＪＩＳ Ｒ５２０１に準じた。Example 1 A papermaking pulp sludge containing about 50% of water and a raw material gypsum were kneaded and mixed in a 1: 1 semi-dry manner without adding water, and a temperature of 140 ° C. and a pressure of 10 were applied during compression molding.
It was kept under kg / cm 2 for 15 minutes, and then released under pressure and allowed to cool. Obtained thickness 12mm, length 300mm, width 300m
The test for bulk specific gravity, bending strength, and compressive strength was performed using a papermaking pulp sludge gypsum board of m. Bulk specific gravity 1.20,
Flexural strength 80 kgf / cm 2 , compressive strength 250 kgf /
cm 2 . The flexural strength conformed to JIS A1408, and the compressive strength conformed to JIS R5201.
【００１２】[0012]
【実施例２】水分５０％程度含有している製紙パルプス
ラッジと図１の原料二水石膏を１：１で水分添加しない
半乾式で混練混合し、圧縮成型後に温度１４０℃、圧力
１０ｋｇ／ｍ２下で１５分間保持し、その後放圧放冷し
て二水石膏が半水石膏化した成型枠をそのまま加水処理
し、実施例１と同様の製紙パルプスラッジ石膏ボードを
得た。かさ比重１．２２、曲げ強さ８１ｋｇｆ／ｃ
ｍ２、圧縮強さは２４７ｋｇｆ／ｃｍ２であった。Example 2 Papermaking pulp sludge containing about 50% of water and raw material dihydrate gypsum of FIG. 1 were kneaded and mixed in a semi-dry system without adding water at a ratio of 1: 1. After compression molding, the temperature was 140 ° C. and the pressure was 10 kg / m. 2 for 15 minutes, and then released under pressure and allowed to cool, and the molding frame in which gypsum dihydrate was converted to hemihydrate gypsum was subjected to water treatment as it was to obtain a papermaking pulp sludge gypsum board similar to that in Example 1. Bulk specific gravity 1.22, bending strength 81 kgf / c
m 2 and the compressive strength were 247 kgf / cm 2 .
【００１３】[0013]
【発明の効果】本発明は高強度の建材用の製紙パルプス
ラッジ石膏ボードの製造にあたり二水石膏を主原料と
し、圧縮成型中もしくはその後に加温加圧して型枠の中
で半水石膏化せしめ、これを再び加水処理して二水石膏
とし、固化することで、従来技術のような半水石膏化せ
しめる多重の焼成工程を省略することができ、併せて、
水と半水石膏の水和によって起きる混合混練工程での機
材への固着固化の排除を可能とした。また、工程の省
略、機材への固着を排除することで、製造工程を簡略化
することができ、コストを低減することもできる。Industrial Applicability According to the present invention, dihydrate gypsum is used as a main raw material in the production of high strength papermaking pulp sludge gypsum board for building materials, and is heated and pressurized during compression molding or thereafter to form hemihydrate gypsum in a mold. In the meantime, this is again subjected to water treatment to form gypsum dihydrate, and by solidification, it is possible to omit the multiple firing steps of making the gypsum hemihydrate as in the prior art.
This makes it possible to eliminate the solidification of equipment in the mixing and kneading process caused by hydration of gypsum with water. Further, by eliminating the steps and eliminating sticking to the equipment, the manufacturing steps can be simplified, and the cost can be reduced.
Claims (3)
石膏と半乾式混合し圧縮成型固化する際に、製紙パルプ
スラッジと二水石膏を半乾式混合する第１工程と、該混
合物を圧縮成型中に温度１２０〜１５０℃、圧力５〜２
０ｋｇ／ｃｍ２下で一定時間保持する第２工程と、その
後放圧放冷して二水石膏が半水石膏化した成型枠をその
まま加水処理する第３工程と、これを成型固化する第４
工程からなることを特徴とする製紙パルプスラッジ石膏
ボードの製造方法。1. A first step of semi-dry mixing papermaking pulp sludge and dihydrate gypsum when the papermaking pulp sludge is semi-dry mixed with dihydrate gypsum using a reinforcing material and compression-solidified, and the mixture is compressed. Temperature 120-150 ° C, pressure 5-2 during molding
A second step of maintaining the pressure at 0 kg / cm 2 for a certain period of time; a third step of subjecting the molded frame in which the gypsum to dihydrate gypsum to hemihydrate gypsum as it is, and a fourth step of molding and solidifying this.
A method for producing a papermaking pulp sludge gypsum board, comprising the steps of:
石膏と半乾式混合し圧縮成型固化する際に、製紙パルプ
スラッジと二水石膏を半乾式混合する第１工程と、該混
合物を圧縮成型する第２工程と、温度１２０〜１５０
℃、圧力５〜２０ｋｇ／ｃｍ２下で一定時間保持する第
３工程と、その後放圧放冷して二水石膏が半水石膏化し
た成型枠をそのまま加水処理する第４工程と、これを成
型固化する第５工程からなることを特徴とする製紙パル
プスラッジ石膏ボードの製造方法。2. A first step of semi-dry mixing papermaking pulp sludge and dihydrate gypsum when the papermaking pulp sludge is semi-dry mixed with dihydrate gypsum using a reinforcing material and compression-molded and solidified, and the mixture is compressed. The second step of molding and a temperature of 120 to 150
C., a third step of maintaining the pressure under a pressure of 5 to 20 kg / cm 2 for a certain period of time; A method for producing a papermaking pulp sludge gypsum board, comprising a fifth step of molding and solidifying.
る製紙パルプスラッジ石膏ボード。3. A papermaking pulp sludge gypsum board produced according to claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21038796A JP3295312B2 (en) | 1996-07-05 | 1996-07-05 | Method for producing paper pulp sludge gypsum board and paper pulp sludge gypsum board |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21038796A JP3295312B2 (en) | 1996-07-05 | 1996-07-05 | Method for producing paper pulp sludge gypsum board and paper pulp sludge gypsum board |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH1015923A true JPH1015923A (en) | 1998-01-20 |
| JP3295312B2 JP3295312B2 (en) | 2002-06-24 |
Family
ID=16588499
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21038796A Expired - Fee Related JP3295312B2 (en) | 1996-07-05 | 1996-07-05 | Method for producing paper pulp sludge gypsum board and paper pulp sludge gypsum board |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3295312B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000036242A1 (en) | 1998-12-11 | 2000-06-22 | Ibiden Co., Ltd. | Composite building material |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101870133B (en) * | 2010-06-02 | 2011-09-28 | 太原理工大学 | Method and device for producing gypsum board |
-
1996
- 1996-07-05 JP JP21038796A patent/JP3295312B2/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2000036242A1 (en) | 1998-12-11 | 2000-06-22 | Ibiden Co., Ltd. | Composite building material |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3295312B2 (en) | 2002-06-24 |
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| LAPS | Cancellation because of no payment of annual fees |