JPH04108644A - Production of cement - Google Patents
Production of cementInfo
- Publication number
- JPH04108644A JPH04108644A JP22520990A JP22520990A JPH04108644A JP H04108644 A JPH04108644 A JP H04108644A JP 22520990 A JP22520990 A JP 22520990A JP 22520990 A JP22520990 A JP 22520990A JP H04108644 A JPH04108644 A JP H04108644A
- Authority
- JP
- Japan
- Prior art keywords
- cement
- concrete
- sulfate
- water
- fluidity
- 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
- 239000004568 cement Substances 0.000 title claims abstract description 49
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 11
- QAOWNCQODCNURD-UHFFFAOYSA-L Sulfate Chemical compound [O-]S([O-])(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-L 0.000 claims abstract description 13
- 238000003860 storage Methods 0.000 claims abstract description 6
- 239000007864 aqueous solution Substances 0.000 claims description 8
- 238000010298 pulverizing process Methods 0.000 claims 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 abstract description 22
- 239000003638 chemical reducing agent Substances 0.000 abstract description 8
- CSNNHWWHGAXBCP-UHFFFAOYSA-L Magnesium sulfate Chemical compound [Mg+2].[O-][S+2]([O-])([O-])[O-] CSNNHWWHGAXBCP-UHFFFAOYSA-L 0.000 abstract description 6
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 abstract description 5
- 229910052938 sodium sulfate Inorganic materials 0.000 abstract description 5
- 235000011152 sodium sulphate Nutrition 0.000 abstract description 5
- 239000007832 Na2SO4 Substances 0.000 abstract description 4
- 229910052943 magnesium sulfate Inorganic materials 0.000 abstract description 3
- 235000019341 magnesium sulphate Nutrition 0.000 abstract description 3
- BAUYGSIQEAFULO-UHFFFAOYSA-L iron(2+) sulfate (anhydrous) Chemical compound [Fe+2].[O-]S([O-])(=O)=O BAUYGSIQEAFULO-UHFFFAOYSA-L 0.000 abstract description 2
- 229910000359 iron(II) sulfate Inorganic materials 0.000 abstract description 2
- 238000000034 method Methods 0.000 description 9
- 230000000694 effects Effects 0.000 description 6
- 230000036571 hydration Effects 0.000 description 6
- 238000006703 hydration reaction Methods 0.000 description 6
- 239000000843 powder Substances 0.000 description 6
- 102000006463 Talin Human genes 0.000 description 3
- 108010083809 Talin Proteins 0.000 description 3
- 238000005507 spraying Methods 0.000 description 3
- 150000003467 sulfuric acid derivatives Chemical class 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 239000011398 Portland cement Substances 0.000 description 2
- 238000004090 dissolution Methods 0.000 description 2
- 229910001653 ettringite Inorganic materials 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- WURBVZBTWMNKQT-UHFFFAOYSA-N 1-(4-chlorophenoxy)-3,3-dimethyl-1-(1,2,4-triazol-1-yl)butan-2-one Chemical compound C1=NC=NN1C(C(=O)C(C)(C)C)OC1=CC=C(Cl)C=C1 WURBVZBTWMNKQT-UHFFFAOYSA-N 0.000 description 1
- BPQQTUXANYXVAA-UHFFFAOYSA-N Orthosilicate Chemical compound [O-][Si]([O-])([O-])[O-] BPQQTUXANYXVAA-UHFFFAOYSA-N 0.000 description 1
- -1 SO4 Chemical class 0.000 description 1
- 229910006130 SO4 Inorganic materials 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 229940037003 alum Drugs 0.000 description 1
- 150000004645 aluminates Chemical class 0.000 description 1
- 229910052925 anhydrite Inorganic materials 0.000 description 1
- JHLNERQLKQQLRZ-UHFFFAOYSA-N calcium silicate Chemical compound [Ca+2].[Ca+2].[O-][Si]([O-])([O-])[O-] JHLNERQLKQQLRZ-UHFFFAOYSA-N 0.000 description 1
- 229910052918 calcium silicate Inorganic materials 0.000 description 1
- 235000012241 calcium silicate Nutrition 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- HOOWDPSAHIOHCC-UHFFFAOYSA-N dialuminum tricalcium oxygen(2-) Chemical compound [O--].[O--].[O--].[O--].[O--].[O--].[Al+3].[Al+3].[Ca++].[Ca++].[Ca++] HOOWDPSAHIOHCC-UHFFFAOYSA-N 0.000 description 1
- 239000002270 dispersing agent Substances 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 230000008020 evaporation Effects 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 229910052500 inorganic mineral Inorganic materials 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 238000004898 kneading Methods 0.000 description 1
- 239000011777 magnesium Substances 0.000 description 1
- 239000011707 mineral Substances 0.000 description 1
- 235000010755 mineral Nutrition 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000004570 mortar (masonry) Substances 0.000 description 1
- CHKVPAROMQMJNQ-UHFFFAOYSA-M potassium bisulfate Chemical compound [K+].OS([O-])(=O)=O CHKVPAROMQMJNQ-UHFFFAOYSA-M 0.000 description 1
- 229910000343 potassium bisulfate Inorganic materials 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- WBHQBSYUUJJSRZ-UHFFFAOYSA-M sodium bisulfate Chemical compound [Na+].OS([O-])(=O)=O WBHQBSYUUJJSRZ-UHFFFAOYSA-M 0.000 description 1
- 229910000342 sodium bisulfate Inorganic materials 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 239000007921 spray Substances 0.000 description 1
- 238000003892 spreading Methods 0.000 description 1
- 239000004575 stone Substances 0.000 description 1
- 230000032258 transport Effects 0.000 description 1
Abstract
Description
【発明の詳細な説明】
［産業上の利用分野］
本発明はセメントの製造方法に係り、特にモルタル又は
コンクリート（以下、コンクリートを例として記す）の
混線時にコンクリートの流動性を向上するために添加す
る分散剤の効果の向上に有効な製造方法に関する。[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing cement, and in particular, a method for producing cement that is added to improve the fluidity of concrete when mixed with mortar or concrete (hereinafter, concrete will be described as an example). The present invention relates to a manufacturing method effective for improving the effect of a dispersant.
［従来の技術］
未硬化コンクリート中の水量が多いと、コンクリートの
流動性が大きいので打設し易いが、硬化後の強度が小と
なるので成可く少量の水で混練することが必要で、コン
クリートの流動性を成可く少量の混練水で得るために、
一般に減水剤が用いられている。[Prior art] When the amount of water in uncured concrete is large, the fluidity of the concrete is high and it is easy to pour, but the strength after hardening is low, so it is necessary to mix it with a small amount of water. In order to obtain the fluidity of concrete with a small amount of mixing water,
Water reducing agents are generally used.
セメントにはセメント鉱物として珪酸三石灰（Ｃ３Ｓ）
、珪酸二石灰（Ｃ２Ｓ）、アルミン酸三石灰（Ｃ３Ａ）
、鉄・アルミン酸四石灰（Ｃ４ＡＦ）等が含有されてお
り、これ等のうちＣ３Ａ及びＣ４ＡＦは水和速度が速く
、コンクリートの注水・混線にあたってＣ３Ｓ及びＣ２
Ｓに先立って水和して水和生成物を生成し、この生成物
が減水剤を吸着してしまい、減水剤の効果を低下させて
いた。Cement contains trilime silicate (C3S) as a cement mineral.
, dicalcium silicate (C2S), tricalcium aluminate (C3A)
, iron/tetralime aluminate (C4AF), etc. Among these, C3A and C4AF have a fast hydration rate, and C3S and C2
Hydration occurs prior to S to produce a hydration product, which adsorbs the water reducing agent, reducing the effectiveness of the water reducing agent.
Ｃ３Ａ及びＣ４ＡＦによる上記の影響を軽減するために
、従来広のような方法が行われていた。In order to reduce the above-mentioned effects caused by C3A and C4AF, methods such as Hiro's have been used in the past.
■セメント中のＣ３Ａ及びＣ４ＡＦ含有量が小さくなる
ような原料配合とする。■The raw materials should be mixed so that the C3A and C4AF contents in the cement are small.
■セメントの粉末度を粗（して、Ｃ３Ａ及びＣ，ＡＦの
多い微粉の生成を減少させる。■ Coarse the cement powder to reduce the production of fine powder containing a lot of C3A, C, and AF.
■セメントに硫酸アルカリ等の溶解速度の太きな硫酸塩
を添加し、注水・混練直後にＣ３Ａ及びＣ４ＡＦの表面
にエトリンガイト（Ｃ３Ａ ・３ＣａＳＯ４・３１ Ｈ
２０）を生成させ、Ｃ３Ａ及びＣ４ＡＦの水和を抑制す
る。■ Add sulfate with a high dissolution rate such as alkali sulfate to cement, and immediately after pouring water and kneading, ettringite (C3A ・3CaSO4 ・31 H
20) and suppresses the hydration of C3A and C4AF.
しかし、これ等の方法には次の問題点があった。However, these methods have the following problems.
■の方法では２セメントタリンカの易焼付が悪くなり燃
料使用量が増加し、また、セメントの初期強度の発現性
が悪くなる。In method (2), the scorching of the two-cement tarinka becomes worse, the amount of fuel used increases, and the initial strength development of the cement becomes worse.
■の方法では、セメントの強度発現性が悪くなる。In method (2), the strength development of the cement becomes poor.
■の方法では、極めて溶解速度の大きな硫酸塩しか使用
できず、しかも、セメント１００重量部に対してＳＯ３
どして０．３重量部程度の少量を使用するので供給方法
が難しい。In method (2), only sulfates with an extremely high dissolution rate can be used, and moreover, SO3 per 100 parts by weight of cement can be used.
Since a small amount of about 0.3 parts by weight is used, the feeding method is difficult.
〔発明が解決しようとする課題］
本発明は、上記従来技術の問題点を解決するために、コ
ンクリートの混線時に添加される減水剤の効果を向上し
得るセメントを製造する方法を提供するものである。[Problems to be Solved by the Invention] In order to solve the above-mentioned problems of the prior art, the present invention provides a method for producing cement that can improve the effect of a water reducing agent added when concrete is mixed. be.
〔課題を解決するための手段１
本発明は上記課題を解決するために、タリン力を粉砕し
てセメントとする粉砕工程及び／又は該セメントを貯槽
に輸送する輸送工程にて、該セメント１００重量部に、
ＳＯ４として０．０２〜１．０重量部の硫酸塩を水溶液
として散布・混合することを特徴とするセメントの製造
方法を提供するものである。[Means for Solving the Problems 1] In order to solve the above-mentioned problems, the present invention provides a process for crushing talin to produce cement and/or a transportation process for transporting the cement to a storage tank. In the department,
The present invention provides a method for producing cement, characterized in that 0.02 to 1.0 parts by weight of sulfate as SO4 is sprinkled and mixed as an aqueous solution.
［作用Ｊ
本発明の方法におけるセメントとしては、各種のポルト
ランドセメント及び混合セメントが適用される。[Operation J] As the cement in the method of the present invention, various Portland cements and mixed cements are used.
本発明において、硫酸塩を含有する水溶液は、例えばタ
リン力を粉砕してセメントとする粉砕機（仕上ミル）内
、粉砕された粉末を精粉（セメント）として分級するセ
パレータ下に設けられた精粉輸送用スクリューコンベア
内、前記スクリューコンベアからセメントを受取り、こ
れを貯槽（サイロ）に輸送するベルトコンベア上、ある
いはこれ等を組合わせて散布されセメントに混合される
。上記の散布・混合場所におけるセメントの温度は６０
℃以上あるので、水溶液中の水分は直に完全に蒸発し、
セメントが貯蔵中に水分により固結することがない。In the present invention, the sulfate-containing aqueous solution is produced, for example, in a pulverizer (finishing mill) that pulverizes talin powder into cement, or a refiner installed below a separator that classifies the pulverized powder as fine powder (cement). It is spread and mixed with cement inside a screw conveyor for transporting powder, on a belt conveyor that receives cement from the screw conveyor and transports it to a storage tank (silo), or in a combination of these. The temperature of the cement at the above spreading/mixing location is 60
Since the temperature is above ℃, the water in the aqueous solution will completely evaporate immediately,
Cement does not harden due to moisture during storage.
硫酸塩としては、水に可溶性のものであれば何れも使用
できるが、溶解度が太き（、比較的安価なＭｇ′ＳＯ４
、ＦｅＳＯ４、Ｎａ２ ＳＯ４。Any sulfate can be used as long as it is soluble in water, but Mg'SO4, which is relatively inexpensive, has a high solubility.
, FeSO4, Na2SO4.
Ｋ２ ＳＯ４、ＮａＨＳＯ４、ＫＨＳＯ４、（ＮＨ４）
２ ＳＯ４、Ａ、Ｊ２２ （ＳＯ４）Ｇ等の硫酸塩、
Ｎａ２ＳＯ４・Ａｆｆ２ （ＳＯ４）３２４、Ｈ２０，
（ＮＨ４）２ ＳＯ４・Ｆｅ２ （Ｓ０４）３・２４８
２０等のみょうばんが好適に用いられる。これ等の硫酸
塩はセメント中のＣ３Ａ及びＣ４ＡＦと直に反応し、Ｃ
３Ａ及びＣ４ＡＦの表面にエトリンガイト（前記）又は
モノサルフェート（Ｃ３Ａ−ＣａＳＯ４・１１Ｈ２０）
を生成してその表面を覆い、Ｃ３Ａ及びＣ４ＡＦが水と
反応して水和生成物を生ずるのを抑制し、これにより減
水剤の水和生成物への吸着が軽減され、コンクリートの
流動性が向上する。K2 SO4, NaHSO4, KHSO4, (NH4)
2 Sulfates such as SO4, A, J22 (SO4)G,
Na2SO4・Aff2 (SO4)324, H20,
(NH4)2 SO4・Fe2 (S04)3・248
Alum such as No. 20 is preferably used. These sulfates react directly with C3A and C4AF in cement,
Ettringite (described above) or monosulfate (C3A-CaSO4・11H20) on the surface of 3A and C4AF
This suppresses the reaction of C3A and C4AF with water to form hydration products, which reduces the adsorption of water reducing agents to the hydration products and improves the fluidity of concrete. improves.
硫酸塩の散布・混合量は、セメント１００重量部に対し
、ＳＯ４として０．０２〜１．０重量％とする。０゜０
２未満では効果が十分でなく、１．０重量％を越えても
効果の増進が認められず、好適には０、１〜０．５重量
％である。The amount of sulfate to be sprayed and mixed is 0.02 to 1.0% by weight as SO4 based on 100 parts by weight of cement. 0゜0
If the amount is less than 2, the effect is insufficient, and if it exceeds 1.0% by weight, no improvement in the effect is observed, and the preferable amount is 0.1 to 0.5% by weight.
硫酸塩を溶解するために用いられる水量は特に限定され
るものではなく、水溶液の調製及び散布・混合操作、散
布・混合時のセメントの温度による水分の完全蒸発等を
劣情して、セメント１００重量部に対して０．３〜１．
５重量部程度である。The amount of water used to dissolve the sulfate is not particularly limited, and considering the preparation of the aqueous solution, the spraying/mixing operation, and the complete evaporation of water due to the temperature of the cement at the time of spraying/mixing, the amount of water used to dissolve the sulfate is not limited to 100% by weight of cement. 0.3 to 1.
The amount is about 5 parts by weight.
上記水溶液の散布・混合にはスプレー等が適宜用いられ
る。A spray or the like is appropriately used for dispersing and mixing the aqueous solution.
［実施例ｊ
実施例１
普通ポルトランドセメントを製造している仕上ミル内に
、タリン力供給側より第１表に示す硫酸マグネシウムの
水溶液を散布してセメントと混合し、得られたセメント
を用い２０℃にてコンクノート試験を行った。[Example j Example 1 An aqueous solution of magnesium sulfate shown in Table 1 was sprayed from the talin power supply side into a finishing mill that manufactures ordinary Portland cement, and mixed with cement. The conch notebook test was conducted at ℃.
なお、コンクリートＩｎ’当りの配合は、セメント４０
０ｋｇ 水１１０ｋｇ、細砂１１ｋｇ、粗砂６８９ｋ
ｇ、砕石１．１５１ ｋ ｇとし、減水剤（マイティ１
５０）の添加量をセメント重量に対して１．６％とした
。In addition, the mixture per concrete In' is cement 40
0kg water 110kg, fine sand 11kg, coarse sand 689kg
g, crushed stone 1.151 kg, water reducing agent (Mighty 1
50) was added in an amount of 1.6% based on the weight of cement.
試験結果を第１表に示す。蒸気養生条件は７０゛Ｃの温
度で３時間保持、オートクレーブ養生条件は１８５°Ｃ
の温度で４時間保持とした。The test results are shown in Table 1. Steam curing conditions were held at a temperature of 70°C for 3 hours, autoclave curing conditions were 185°C.
The temperature was maintained for 4 hours.
硫酸マグネシウムの水溶液を散布・混合することにより
、コンクリートのスランプ発現性が良好となり、スラン
プロスも少なくなった。したがって、スランプ一定とし
てコンクリートをｌｉＨすれば混線水を減少させること
ができ、コンクリートの強度を増大し得る。Spraying and mixing an aqueous solution of magnesium sulfate improved the slump development of concrete and reduced slump loss. Therefore, if concrete is subjected to LiH with a constant slump, crosstalk water can be reduced and the strength of concrete can be increased.
実施例２
普通ポルトランドセメントを製造しでいる仕上ミルのセ
パレータ下の精粉（セメント）輸送用スクリューコンベ
ア内に、第２表に示す硫酸ナトリウム（Ｎａ２ ＳＯ４
）の水溶液を散布して混合し、得られたセメントを用い
てコンクリート試験を行った。コンクリート試験の条件
は実施例１と同様であった。Example 2 Sodium sulfate (Na2SO4
) was sprinkled and mixed, and a concrete test was conducted using the resulting cement. The conditions for the concrete test were the same as in Example 1.
試験結果を第２表に示す。The test results are shown in Table 2.
実施例１と同様、スランプ発現性が良好となり、スラン
プロスも少なくなった。As in Example 1, the slump development property was good and the slump loss was also reduced.
［発明の効果１
本発明によるセメントの製造方法により■従来のセメン
トを用いた場合より、同一条件下で混練したコンクリー
トの流動性が良くなる。[Effect of the invention 1] The method for producing cement according to the present invention improves the fluidity of concrete mixed under the same conditions as compared to the case where conventional cement is used.
■従来のセメントを用いたコンクリートと同一流動性を
得るのに水量及び減水剤使用量を減らすことができるの
で、コンクリートの強度発現性が良くなり、製造原価が
下がる。■Since the amount of water and water reducing agent used can be reduced to obtain the same fluidity as conventional concrete using cement, the strength development of concrete is improved and manufacturing costs are reduced.
Claims (1)
又は該セメントを貯槽に輸送する輸送工程にて、該セメ
ント１００重量部に、 ＳＯ＿４として０．０２〜１．０重量部の硫酸塩を水溶
液として散布・混合することを特徴とするセメントの製
造方法。[Claims] 1. A pulverizing step of pulverizing clinker to make cement; and/or
Or a method for producing cement, characterized in that, in the transportation step of transporting the cement to a storage tank, 0.02 to 1.0 parts by weight of sulfate as SO_4 is sprinkled and mixed as an aqueous solution to 100 parts by weight of the cement. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22520990A JP2776018B2 (en) | 1990-08-29 | 1990-08-29 | Manufacturing method of cement |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22520990A JP2776018B2 (en) | 1990-08-29 | 1990-08-29 | Manufacturing method of cement |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04108644A true JPH04108644A (en) | 1992-04-09 |
| JP2776018B2 JP2776018B2 (en) | 1998-07-16 |
Family
ID=16825696
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22520990A Expired - Lifetime JP2776018B2 (en) | 1990-08-29 | 1990-08-29 | Manufacturing method of cement |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2776018B2 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07157347A (en) * | 1993-12-01 | 1995-06-20 | Sumitomo Osaka Cement Co Ltd | Cement composition, production and hardened body thereof |
-
1990
- 1990-08-29 JP JP22520990A patent/JP2776018B2/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07157347A (en) * | 1993-12-01 | 1995-06-20 | Sumitomo Osaka Cement Co Ltd | Cement composition, production and hardened body thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2776018B2 (en) | 1998-07-16 |
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