JP3154796B2 - Composition for promoting hardening of cement and method for producing the same - Google Patents
Composition for promoting hardening of cement and method for producing the sameInfo
- Publication number
- JP3154796B2 JP3154796B2 JP7934192A JP7934192A JP3154796B2 JP 3154796 B2 JP3154796 B2 JP 3154796B2 JP 7934192 A JP7934192 A JP 7934192A JP 7934192 A JP7934192 A JP 7934192A JP 3154796 B2 JP3154796 B2 JP 3154796B2
- Authority
- JP
- Japan
- Prior art keywords
- cement
- concrete
- composition
- hydrate
- curing
- 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.)
- Expired - Fee Related
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
- C04B18/00—Use of agglomerated or waste materials or refuse as fillers for mortars, concrete or artificial stone; Treatment of agglomerated or waste materials or refuse, specially adapted to enhance their filling properties in mortars, concrete or artificial stone
- C04B18/04—Waste materials; Refuse
- C04B18/16—Waste materials; Refuse from building or ceramic industry
-
- 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
- C04B2103/00—Function or property of ingredients for mortars, concrete or artificial stone
- C04B2103/10—Accelerators; Activators
- C04B2103/14—Hardening accelerators
-
- 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
- Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Civil Engineering (AREA)
- Ceramic Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Materials Engineering (AREA)
- Structural Engineering (AREA)
- Organic Chemistry (AREA)
- Curing Cements, Concrete, And Artificial Stone (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、コンクリート廃棄物ま
たは生コンクリート工場やコンクリート製品工場におい
てコンクリート製造工程で発生するスラッジから得られ
るセメントの硬化促進組成物およびそれを製造する方法
に関する。さらに詳しくは、本発明は、コンクリート構
造物の解体に伴って発生するコンクリート廃棄物または
コンクリート製造工程で発生するスラッジからセメント
水和物またはセメント未水和物を高割合で含む微粉部分
を回収し、これをセメントの硬化促進組成物として再利
用するための技術に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition for accelerating hardening of cement obtained from concrete waste or sludge generated in a concrete manufacturing process in a ready-mixed concrete plant or a concrete product plant, and a method for producing the same. More specifically, the present invention recovers a fine powder portion containing a high proportion of cement hydrate or cement non-hydrate from concrete waste generated in the demolition of a concrete structure or sludge generated in a concrete manufacturing process. The present invention relates to a technology for reusing this as a hardening accelerator composition for cement.
【０００２】[0002]
【従来の技術および問題点】近年、コンクリート構造物
の解体に伴って発生するコンクリート廃棄物の量が急速
に増加してきている。従来、コンクリート構造物の解体
にともなって発生するコンクリート廃棄物の再利用とし
て、コンクリート廃棄物を粉砕し、ふるい分けを行い、
各種骨材を取り出して、コンクリート用骨材として再利
用しようとの試みが行われてきた。しかしながら、コン
クリート骨材として再利用する部分以外の残りである、
セメント水和物を高割合で含む微粉部分の再利用につい
てはまだ十分に検討されていない。また、生コンクリー
ト工場やコンクリート製品工場で発生するスラッジはセ
メント分を多量に含んでいるため、環境保全の面より、
そのまま廃棄することができず、その再利用はｐＨ調整
用の土壌改良材や脱水して固形化することにより路盤材
などとして再利用することが検討されているが、まだ実
用化の域に至っていない。仮に、実用化されても、その
使用量は少なく、問題の解決にはならないであろう。2. Description of the Related Art In recent years, the amount of concrete waste generated due to demolition of concrete structures has been rapidly increasing. Conventionally, concrete waste is crushed and sieved as reuse of concrete waste generated by demolition of concrete structures.
Attempts have been made to extract various aggregates and reuse them as concrete aggregates. However, it is the rest except for the part that is reused as concrete aggregate.
Reuse of fine powder fractions containing a high proportion of cement hydrate has not yet been fully investigated. In addition, since sludge generated in ready-mixed concrete factories and concrete product factories contains a large amount of cement, from the viewpoint of environmental protection,
It cannot be discarded as it is, and its reuse is being studied as soil improvement material for pH adjustment or as roadbed material by dehydration and solidification, but it has not yet reached practical use. Not in. Even if it is put to practical use, its usage will be small and will not solve the problem.
【０００３】[0003]
【発明が解決しようとする課題】本発明の目的は、コン
クリート構造物を解体する時に発生するコンクリート廃
棄物または生コンクリート工場やコンクリート製品工場
で発生するスラッジからセメント水和物またはセメント
未水和物を高割合で含む微粉部分を取出し、これから良
好なセメントの硬化促進組成物を製造する技術を提供す
ることにある。SUMMARY OF THE INVENTION An object of the present invention is to provide a cement hydrate or a cement non-hydrate from concrete waste generated when dismantling a concrete structure or sludge generated in a ready-mixed concrete factory or a concrete product factory. The present invention is to provide a technique for extracting a fine powder portion containing a high proportion of, and producing a favorable cement hardening promoting composition therefrom.
【０００４】[0004]
【課題を解決するための手段】本発明は、コンクリート
廃棄物の破砕物またはコンクリート製造工程で発生する
スラッジをふるい分けしてセメント水和物またはセメン
ト未水和物を高割合で含む微粉部分を取出し、これに水
または水とセメントを添加し、硬化・成形するか、また
は、加圧成形し、次いでオートクレーブ養生を行い、さ
らに微粉砕することを特徴とするセメントの硬化促進組
成物の製造方法を提供する。SUMMARY OF THE INVENTION According to the present invention, a crushed concrete waste or a sludge generated in a concrete manufacturing process is sieved to remove a fine powder portion containing a high proportion of hydrated cement or unhydrated cement. Add water or water and cement thereto, and cure or mold, or press-mold, then perform autoclave curing, and further produce a method for producing a cement curing acceleration composition characterized by further pulverizing. provide.
【０００５】本発明は、さらにコンクリート廃棄物の破
砕物またはコンクリート製造工程で発生するスラッジか
ら回収した、セメント水和物またはセメント未水和物を
高割合で含む微粉部分を成形し、オートクレーブ養生し
てなる生成物からなることを特徴とするセメント硬化促
進組成物を提供する。According to the present invention, a fine powder portion containing a high proportion of cement hydrate or cement non-hydrate recovered from crushed concrete waste or sludge generated in the concrete manufacturing process is further formed and autoclaved. The present invention provides a cement setting accelerator composition comprising a product comprising:
【０００６】本発明の方法においては、先ず、コンクリ
ート廃棄物をジョークラッシャーその他適当な粗砕機を
用いて破砕し、適当な目開きのふるいを用いて破砕物か
ら骨材を除き、セメント水和物またはセメント未水和物
を高割合で含む微粉部分を取出す。または、生コンクリ
ート工場やコンクリート製品工場においてコンクリート
製造工程で発生するスラッジを適当な目開きのふるいを
用いてふるい分けしてセメント水和物またはセメント未
水和物を高割合で含む微粉部分を取り出す。ふるいの目
の大きさは３mm〜0.15mm程度が好ましい。In the method of the present invention, first, concrete waste is crushed using a jaw crusher or other suitable crusher, and aggregates are removed from the crushed material using a suitable opening sieve to remove cement hydrate. Alternatively, a fine powder portion containing a high proportion of cement unhydrate is taken out. Alternatively, sludge generated in the concrete manufacturing process at a ready-mixed concrete plant or a concrete product plant is sieved using a sieve having an appropriate opening to take out a fine powder portion containing a high proportion of hydrated cement or unhydrated cement. The sieve mesh size is preferably about 3 mm to 0.15 mm.
【０００７】取出した微粉部分は、適当量の水または水
とセメントを添加し、硬化・成形するか、または加圧成
形する。次いで、成形物はオートクレーブ中で養生す
る。オートクレーブ中で養生することにより、微粉部分
中のカルシウムシリケート水和物は結晶性の高いものと
なる。結晶性の高いカルシウムシリケート水和物は非常
に大きな比表面積を有しており、これをセメントに添加
して水和させた場合、添加した水和物表面は新たに生成
する水和物の結晶核となりやすいために、セメントの主
にエーライトの水和を早め、硬化を促進する。特に、セ
メントの水和を著しく遅延する糖類のようなに遅延性物
質が同時に存在する場合には著しい効果を発揮する。す
なわち、結晶性の高いカルシウムシリケート水和物の結
晶表面が遅延性物質を物理的あるいは化学的に吸着し、
溶液中に存在する遅延性物質を減少させ、上記の結晶核
生成の効果と合わせてセメントの水和を早め硬化を促進
するからである。[0007] The removed fine powder portion is added with an appropriate amount of water or water and cement, and is cured and molded, or is subjected to pressure molding. Subsequently, the molding is cured in an autoclave. By curing in an autoclave, the calcium silicate hydrate in the fine powder portion becomes highly crystalline. Highly crystalline calcium silicate hydrate has a very large specific surface area, and when it is added to cement and hydrated, the surface of the added hydrate becomes a crystal of newly formed hydrate. As it easily becomes a core, it accelerates the hydration of cement, mainly alite, and promotes hardening. In particular, a remarkable effect is exhibited when a retarding substance such as a saccharide which significantly delays the hydration of cement is present at the same time. In other words, the crystalline surface of the highly crystalline calcium silicate hydrate physically or chemically adsorbs the retardant,
This is because the amount of the retardant substance present in the solution is reduced, and the effect of the crystal nucleation is accelerated to accelerate the hydration of the cement and promote the hardening.
【０００８】オートクレーブ養生の条件は格別限定され
るものではないが、１００℃〜３００℃にて養生するこ
とが好ましい。また、養生の効果は、セメント成形体中
のＣａＯ／ＳｉＯ2 モル比が０．５〜３．０のとき顕著
である。このような結晶性の良いカルシウムシリケート
水和物は、常温養生または蒸気養生を行った際に生成す
る低結晶性のカルシウムシリケート水和物から容易にオ
ートクレーブ養生することで得ることができ、産業廃棄
物としてその処理に苦慮している廃棄コンクリートまた
は生コンクリート工場やコンクリート製品工場で発生す
るスラッジ中のセメント分は、セメント水和物または未
水和のセメントを多く含んでいることから、前述のセメ
ントの硬化促進組成物を製造する原料として好適であ
る。オートクレーブ養生した後、微粉砕して、目的とす
るセメントの硬化促進組成物が得られる。The conditions for the autoclave curing are not particularly limited, but it is preferable to cure at 100 ° C. to 300 ° C. The effect of curing is, CaO / SiO 2 molar ratio in the cement moldings is remarkable when 0.5 to 3.0. Such a crystalline calcium silicate hydrate having good crystallinity can be obtained by easily autoclaving a low-crystalline calcium silicate hydrate formed when subjected to room temperature curing or steam curing, and industrial waste can be obtained. The cement content in waste concrete or sludge generated in ready-mixed concrete factories and concrete product factories that are having difficulty in the treatment of waste products contains a large amount of cement hydrate or unhydrated cement. It is suitable as a raw material for producing the above-mentioned curing accelerator composition. After curing in an autoclave, the mixture is pulverized to obtain the desired cement accelerator composition.
【０００９】[0009]
【実施例】以下、実施例について本発明のセメントの硬
化促進組成物の製造方法を具体的に説明する。実施例１ 材令が１年以上を経過した普通コンクリート供試体をジ
ョークラッシャーで粗砕した後、目開きが０．３ｍｍの
ふるいでふるい分けて骨材を取り除き、セメント水和物
または未水和セメントを高割合で含むセメント部分を取
出し、セメントの硬化促進組成物用原料とした。この原
料の不溶残分から求めたセメント分は４６．９重量％で
ある。上記硬化促進組成物原料に市販の普通ポルトラン
ドセメントを内割で３０重量％と水／粉体比＝０．３と
なるように水を添加し、十分に混練した後、φ５０ｍｍ
×１００ｍｍの型枠で成形した。成形後２４時間を経過
してから脱型し、２日間２０℃、８０％ＲＨで湿空養生
を行い、オートクレーブ養生を行うための成形体を作製
した。この成形体を１５３℃、１０時間のオートクレー
ブ養生を行い、その後、粉末度を５０００ｃｍ2 ／ｇに
までボールミルで微粉砕して、セメントの硬化促進組成
物を得た。EXAMPLES The production method of the composition for accelerating hardening of the cement of the present invention is specifically described below with reference to examples. Example 1 An ordinary concrete specimen whose material age has passed one year or more is coarsely crushed with a jaw crusher, and then sieved with a sieve having an opening of 0.3 mm to remove aggregates, and cement hydrate or unhydrated cement. Was taken out and used as a raw material for a cement hardening promoting composition. The cement content determined from the insoluble residue of this raw material was 46.9% by weight. Water is added to the above-mentioned hardening accelerator composition raw material so as to have a weight ratio of a commercially available ordinary Portland cement of 30% by weight and a water / powder ratio of 0.3, and the mixture is sufficiently kneaded.
It was molded in a × 100 mm formwork. After 24 hours from the molding, the mold was released, and subjected to wet-air curing at 20 ° C. and 80% RH for 2 days to prepare a molded article for autoclave curing. The molded body was subjected to autoclave curing at 153 ° C. for 10 hours, and then finely pulverized with a ball mill to a fineness of 5000 cm 2 / g to obtain a cement setting promoting composition.
【００１０】上記硬化促進組成物をセメントの内割で５
重量％混合して、ＪＩＳ Ｒ ５２０１に準じてモルタ
ルを成形し、材令１日まで２０℃，８５％ＲＨの湿空養
生を行った後、脱型し、材令３，７または２８日まで２
０℃で水中養生を行ったモルタルの圧縮強さを測定し
た。その結果を表１に示すが、各材令において、本発明
方法により得られるセメントの硬化促進組成物を添加す
ることによってセメントの硬化が促進され、モルタルの
強さが増加していることがわかる。[0010] The hardening promoting composition is divided into 5 parts of cement.
% By weight, form a mortar according to JIS R 5201, cure at 20 ° C. and 85% RH until the material age is 1 day, remove it from the mold, and until the material age 3, 7 or 28 days 2
The compressive strength of the mortar cured at 0 ° C. in water was measured. The results are shown in Table 1. It can be seen that in each material age, the setting of the cement was accelerated by adding the setting accelerator for the cement obtained by the method of the present invention, and the strength of the mortar was increased. .
【００１１】[0011]
【表１】 [Table 1]
【００１２】実施例２ 実施例１で示した硬化促進組成物をセメントの内割で５
重量％混合して、さらにセメントの硬化遅延物として試
薬サッカロースを全粉体の０．１重量％添加し、ＪＩＳ
Ｒ ５２０１に準じてモルタルを成形し、５０℃，１
００％ＲＨで湿空養生を２４時間行い、モルタルの圧縮
強さを測定した。その結果を表２に示す。普通ポルトラ
ンドセメントモルタルは硬化が阻害され、モルタル強さ
が低下しているにもかかわらず、本発明が示すセメント
の硬化促進組成物を添加したモルタルは十分に硬化し、
強さを発現しているのがわかる。 Example 2 The hardening accelerating composition shown in Example 1 was divided into 5 parts of cement.
% Of the total powder and 0.1% by weight of a saccharose reagent as a cement setting retarder based on JIS
Mortar is molded in accordance with R5201, 50 ° C, 1
Moist air curing was performed at 00% RH for 24 hours, and the compressive strength of the mortar was measured. Table 2 shows the results. Normally Portland cement mortar is inhibited from hardening, despite the decrease in mortar strength, the mortar to which the hardening composition of the cement according to the present invention is added sufficiently hardens,
It can be seen that strength is developed.
【００１３】[0013]
【表２】 [Table 2]
【００１４】[0014]
【発明の効果】本発明方法によればコンクリート廃棄物
またはコンクリート製造工程で発生スラッジから良好な
セメント硬化促進組成物を得ることができる。このセメ
ント硬化促進組成物を配合して製造されるコンクリート
製品は、上記実施例に示されるように、硬化が促進さ
れ、強度が向上する。特に、セメントの水和を著しく遅
延する糖類のような遅延性物質が共存する場合には、硬
化促進および強度向上の効果は顕著である。According to the method of the present invention, a good cement hardening promoting composition can be obtained from concrete waste or sludge generated in the concrete manufacturing process. As shown in the above examples, concrete products manufactured by blending this cement hardening promoting composition are promoted in hardening and improved in strength. In particular, when a retarding substance such as a saccharide that significantly delays hydration of cement is present, the effects of accelerating hardening and improving strength are remarkable.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 横田 紀男 千葉県船橋市豊富町585番地 住友セメ ント株式会社中央研究所内 (72)発明者 内田 清彦 千葉県船橋市豊富町585番地 住友セメ ント株式会社中央研究所内 (56)参考文献 特開 昭61−155234（ＪＰ，Ａ) 特開 平５−238790（ＪＰ，Ａ) 特開 平５−238791（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) C04B 7/00 - 28/36 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Norio Yokota 585 Tomicho, Funabashi-shi, Chiba Sumitomo Cement Co., Ltd. (72) Inventor Kiyohiko Uchida 585 Tomicho, Funabashi-shi, Chiba Sumitomo Cement Co., Ltd. (56) References JP-A-61-155234 (JP, A) JP-A-5-238790 (JP, A) JP-A-5-238791 (JP, A) (58) Fields studied (Int. Cl. 7 , DB name) C04B 7/ 00-28/36
Claims (3)
クリート製造工程で発生するスラッジをふるい分けして
セメント水和物またはセメント未水和物を高割合で含む
微粉部分を取出し、これに水または水とセメントを添加
し、硬化・成形するか、または、加圧成形し、次いでオ
ートクレーブ養生を行い、さらに微粉砕することを特徴
とするセメント硬化促進組成物の製造方法。1. A crushed concrete waste or a sludge generated in a concrete manufacturing process is sieved to take out a fine powder portion containing a high proportion of hydrated cement or unhydrated cement. , And curing or molding, or pressure molding, then autoclaving, and further pulverizing the composition.
０である成形物をオートクレーブ養生する請求項１記載
のセメント硬化促進組成物の製造方法。2. The CaO / SiO 2 molar ratio is 0.5-3.
The method for producing a cement hardening accelerating composition according to claim 1, wherein the molded product having a value of 0 is subjected to autoclave curing.
クリート製造工程で発生するスラッジから回収した、セ
メント水和物またはセメント未水和物を高割合で含む微
粉部分を成形し、オートクレーブ養生してなる生成物か
らなることを特徴とするセメント硬化促進組成物。3. A method of forming a fine powder portion containing a high proportion of cement hydrate or cement non-hydrate recovered from crushed concrete waste or sludge generated in the concrete manufacturing process, followed by autoclave curing. A cement hardening accelerating composition comprising:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7934192A JP3154796B2 (en) | 1992-02-29 | 1992-02-29 | Composition for promoting hardening of cement and method for producing the same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7934192A JP3154796B2 (en) | 1992-02-29 | 1992-02-29 | Composition for promoting hardening of cement and method for producing the same |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05238794A JPH05238794A (en) | 1993-09-17 |
| JP3154796B2 true JP3154796B2 (en) | 2001-04-09 |
Family
ID=13687202
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7934192A Expired - Fee Related JP3154796B2 (en) | 1992-02-29 | 1992-02-29 | Composition for promoting hardening of cement and method for producing the same |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3154796B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4171195B2 (en) * | 2001-09-04 | 2008-10-22 | 太平洋セメント株式会社 | Cement extender |
| US6648962B2 (en) * | 2001-09-06 | 2003-11-18 | W. R. Grace & Co.-Conn. | Micro-granulose particulates |
| JP3678732B2 (en) * | 2003-09-11 | 2005-08-03 | 住友大阪セメント株式会社 | Partially hydrated molded body of hydraulic composition, method for producing the same and method for using the same |
| JP7141867B2 (en) * | 2018-06-28 | 2022-09-26 | Ｕｂｅ三菱セメント株式会社 | Strength enhancer and method for producing the same |
-
1992
- 1992-02-29 JP JP7934192A patent/JP3154796B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH05238794A (en) | 1993-09-17 |
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