JP3580868B2 - Coal ash treatment method - Google Patents
Coal ash treatment method Download PDFInfo
- Publication number
- JP3580868B2 JP3580868B2 JP21658994A JP21658994A JP3580868B2 JP 3580868 B2 JP3580868 B2 JP 3580868B2 JP 21658994 A JP21658994 A JP 21658994A JP 21658994 A JP21658994 A JP 21658994A JP 3580868 B2 JP3580868 B2 JP 3580868B2
- Authority
- JP
- Japan
- Prior art keywords
- coal ash
- coal
- unburned
- flotation
- ash
- 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
Images
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
- C04B18/06—Combustion residues, e.g. purification products of smoke, fumes or exhaust gases
-
- 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
Description
【０００１】
【産業上の利用分野】
この発明は、セメント、コンクリートや建材の原料等に用いられる石炭灰（フライアッシュ）の処理方法に関するものである。
【０００２】
【従来の技術】
石炭灰は微粉炭焚きボイラ等から発生するが、この石炭灰の中には未燃炭分が含まれている。この未燃炭分は、石炭灰を利用する上で次のような問題を引き起こす。例えば、セメント混和材として石炭灰を利用する場合、石炭灰中に未燃炭分が含まれていると、コンクリート混練時に高価な空気連行剤（ＡＥ剤）が未燃炭分に吸収されるため、多量の空気連行剤が必要となる。また人工軽量骨材等の原料として石炭灰を利用する場合、原料中に多くの未燃炭分が含まれていると、骨材等の強熱減量（Ｉｇ−Ｌｏｓｓ）が大きくなる。
【０００３】
そのため、未燃炭分の少ない石炭灰だけをコンクリートの原料等に利用し、未燃炭分の多く含まれている石炭灰は利用されず産業廃棄物として捨てられる。しかし、建材等の原料として有効な石炭灰を廃棄することは不経済であり、またその廃棄処理には多くの費用が必要となる。
【０００４】
そこで従来浮遊選鉱、即ち石炭灰の水スラリに捕集剤を添加して未燃炭分を疎水化させる疎水化工程と、該水スラリに起泡剤を添加して気泡を発生させ、その気泡に前記未燃炭分を付着させ浮上させる浮選工程とを備えた石炭灰の処理工程により石炭灰から未燃炭分を分離している。
【０００５】
【発明が解決しようとする課題】
従来の石炭灰の処理方法は、大量処理が可能であると言う長所を有するが、その反面、未燃炭分の除去率が低く、石炭灰中の未燃炭分を効率よく分離できないという問題がある。
【０００６】
この発明は、上記事情に鑑み石炭灰中の未燃炭分を効率よく分離できるようにすることを目的とする。
【０００７】
【課題を解決するための手段】
上記目的を達成するために、この発明の石炭灰の処理方法によれば、石炭灰の水スラリに捕集剤を添加して未燃炭分を疎水化させる疎水化工程と、該水スラリに起泡剤を添加して気泡を発生させ、その気泡に前記未燃炭分を付着させ浮上させる浮選工程とを備えた石炭灰の浮選処理方法において、あらかじめ石炭灰を風力分級することにより石炭灰の粗大粒子を除去し、石炭灰粒子の８８μｍ篩上残分値を３重量％以下とした石炭灰を浮選処理に供することを特徴とする。以下、この発明を詳しく説明する。
【０００８】
石炭灰は、空気分級機等により風力分級し、あらかじめ粗大粒子を取り除く。この石炭灰を用いて浮選処理を行うことにより、未燃炭分の除去率を大幅に高めることができる。これは、石炭灰中に粗大粒子が存在すると、疎水化工程において添加する捕集剤等の界面活性剤の影響により、粗大な未燃炭分粒子が核となり粒子成長を起こすことで、より粗大な粒子に成長するため浮選工程において未燃炭分を浮上させることが困難になることが考えられるが、あらかじめ粗大粒子を除去することで、この影響をなくし、効率的な浮選処理を行うことができる。石炭灰の粗大粒子は、８８μｍ篩上残分値が３重量％以下となるように風力（空気）分級することが好ましい。すなわち、風力分級により石炭灰粒子の８８μｍ篩上残分値を３重量％以下とした石炭灰を浮選処理に供する。これが３重量％を越えると、前述した影響をなくし、未燃炭分の除去率を高めることができなくなる。
【０００９】
次に、疎水化工程で使用する捕集剤として重油、灯油等、又、浮選工程で使用する起泡剤としてパイン油等従来公知のものを使用できるが、特に捕集剤としては、イオン性捕集剤を単独もしくは無極性試薬と混合しエマルジョン化したものが好適に使用できる。イオン性捕集剤としてはアルキルアミン、アルキルアンモニウム、ザンセート、オレイン酸、アルキル硫酸塩、アルキルスルフォン酸塩等が挙げられ、中でもアルキルアミン、アルキルスルフォン酸塩は未燃炭分の疎水化に極めて優れイオン性捕集剤として好適に用いることができる。無極性試薬としてはケロシン、キシレン、シクロヘキサン、デカン等が好適に用いられる。エマルジョン化としてはイオン性捕集剤と無極性試薬の混合液に超音波をかける他、攪拌、振とう等、いずれの方法を用いても良い。
【００１０】
【作用】
石炭灰スラリに捕集剤を添加することで未燃炭分を疎水化させるとともに、該水スラリに起泡剤を添加し気泡を発生させ、その気泡表面に未燃炭分を付着し上昇させるとき、あらかじめ８８μｍ篩上残分値が３重量％以下となるように石炭灰を風力分級し、粗大粒子を除去した石炭灰、すなわち、石炭灰粒子の８８μｍ篩上残分値を３重量％以下とした石炭灰を使用することで、未燃炭分を上昇しやすくする。
【００１１】
【実施例】
実施例１
原粉のＩｇ−Ｌｏｓｓ（強熱減量）が９．０重量％（以下％は、いずれも重量％を示す）、８８μｍ篩上残分値が６．１％の石炭灰を空気分級機（アキュカットＡ−１２：（株）日本ドナルドソン社製）で分級点を変化させ分級を行い、粗大粒子の除去された８８μｍ残分値がそれぞれ２．６％，２．３％，１．５％の石炭灰を得た（分級工程）。原粉及び分級された石炭灰それぞれ８０ｇと水８００ｍｌを浮選槽に攪拌しながら混合して水スラリにし、これに捕集剤として石油スルフォン剤水溶液（濃度１．０重量％）を２．０ｍｌ添加し、攪拌しながら３分間放置し、石炭灰中の未燃炭分を疎水化させる（疎水化工程）。疎水化工程の後、前記水スラリに起泡剤としてパイン油を６０ｍｇ添加すると共に、浮選槽の底部から空気を吹き込み気泡を発生させ、該気泡に未燃炭分を付着させ浮上させる。この浮上した気泡をオ−バ−フロ−分として取り出す。この工程を３分間継続して行った（浮選工程）。次いでオ−バ−フロ−分を取り除いた石炭灰のＩｇ−Ｌｏｓｓを測定した。
【００１２】
浮選処理した石炭灰のＩｇ−Ｌｏｓｓと８８μｍ残分値の関係を図１に示す。これから分かるように分級点を下げ、８８μｍ残分を下げることにより処理後Ｉｇ−Ｌｏｓｓは減少している。しかし、ある程度以上８８μｍを下げると、それ以上処理後Ｉｇ−Ｌｏｓｓは減少しなくなる。これは、ある一定以上の大きさの粒子のみが浮選工程に影響しているためだと考えられる。
【００１３】
実施例２
Ｉｇ−Ｌｏｓｓが異なる３種類の石炭灰（原粉）を空気分級機（アキュカットＡ−１２：日本ドナルドソン）により、同一条件（空気量、ブレード回転数、原料供給速度一定）で分級を行い、粗大粒子を除去した。結果を表１に示す。未燃炭分は粗大粒子側に多く存在するため分級することによりＩｇ−Ｌｏｓｓはわずかながら減少している。
【００１４】
【表１】
次に、原粉及び分級した石炭灰それぞれ８０ｇと水８００ｍｌを浮選槽に攪拌しながら混合して水スラリにし、これに捕集剤として石油スルフォン剤水溶液（濃度１．０重量％）を２．０ｍｌ添加し、攪拌しながら３分間放置した（疎水化工程）。これにより石炭灰中の未燃炭分を疎水化させる。疎水化工程の後、前記水スラリに起泡剤としてパイン油を６０ｍｇ添加し浮選槽の底部から空気を吹き込み気泡を発生させ、該気泡に未燃炭分を付着させ浮上させた（浮選工程）。次いでオ−バ−フロ−分を取り除いた石炭灰のＩｇ−Ｌｏｓｓを測定した。
【００１６】
分級石炭灰で前記浮選処理を行ったときの未燃炭分除去率を、分級処理を行わず原粉で浮選処理を行った結果と比較して図２に示した。この未燃炭分除去率は浮選処理前Ｉｇ−Ｌｏｓｓを処理後Ｉｇ−Ｌｏｓｓで割ったものであり、この値が高いほど処理効果が大きいことを示す。これからＩｇ−Ｌｏｓｓの異なる石炭灰を使用し処理を行っても、分級処理を行うことで未燃炭分除去率は上昇することが分かった。
【００１７】
【発明の効果】
本発明は、８８μｍ篩上残分値が３重量％以下となるように石炭灰を風力分級し粗大粒子を除去した石炭灰、すなわち、風力分級により石炭灰粒子の８８μｍ篩上残分値を３重量％以下とした石炭灰を用いて浮選処理を行うことにより、石炭灰の未燃炭分を効率よく除去することが出来る。
【図面の簡単な説明】
【図１】実施例１における８８μｍ残分値と浮選処理した石炭灰のＩｇ−Ｌｏｓｓの関係を示すグラフである。
【図２】実施例２における分級品石炭灰と分級されていない石炭灰の浮選処理による未燃炭分除去率を示すグラフである。[0001]
[Industrial applications]
The present invention relates to a method for treating coal ash (fly ash) used as a raw material for cement, concrete, building materials, and the like.
[0002]
[Prior art]
Coal ash is generated from pulverized coal-fired boilers and the like, and this coal ash contains unburned coal. This unburned coal causes the following problems in utilizing coal ash. For example, when coal ash is used as a cement admixture, if unburned coal is contained in coal ash, an expensive air entraining agent (AE agent) is absorbed by the unburned coal during kneading of concrete, so that a large amount of coal is used. Of air entraining agent is required. In the case where coal ash is used as a raw material for artificial lightweight aggregate or the like, if a large amount of unburned coal is contained in the raw material, the ignition loss (Ig-Loss) of the aggregate or the like increases.
[0003]
Therefore, only coal ash containing a small amount of unburned coal is used as a raw material for concrete, and coal ash containing a large amount of unburned coal is not used and is discarded as industrial waste. However, it is uneconomical to dispose of effective coal ash as a raw material for building materials and the like, and the disposal thereof requires a lot of cost.
[0004]
Therefore, conventional flotation, i.e., a hydrophobizing step of adding a trapping agent to a water slurry of coal ash to hydrophobize the unburned coal content, and adding a foaming agent to the water slurry to generate bubbles, The unburned coal content is separated from the coal ash by a coal ash treatment process including a flotation process of attaching and floating the unburned coal content.
[0005]
[Problems to be solved by the invention]
The conventional method of treating coal ash has the advantage that large-scale treatment is possible, but on the other hand, there is a problem that the removal rate of unburned coal is low and the unburned coal in coal ash cannot be efficiently separated. .
[0006]
The present invention has been made in view of the above circumstances, and has as its object to enable efficient separation of unburned coal in coal ash.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, according to the method for treating coal ash of the present invention, a hydrophobizing step of adding a collector to a water slurry of coal ash to hydrophobize unburned coal is provided. A flotation step of adding a foaming agent to generate air bubbles, adhering the unburned coal to the air bubbles, and floating the coal ash. Of coal ash particles having a residual value of 3% by weight or less on the 88 μm sieve of coal ash particles is subjected to a flotation treatment. Hereinafter, the present invention will be described in detail.
[0008]
Coal ash is air-classified by an air classifier or the like to remove coarse particles in advance. By performing the flotation treatment using the coal ash, the removal rate of the unburned coal can be greatly increased. This is because, when coarse particles are present in the coal ash, coarse unburned coal particles become nuclei and cause particle growth due to the effect of a surfactant such as a collecting agent added in the hydrophobizing step, so that more coarse particles are formed. It is thought that it is difficult to raise unburned coal in the flotation process due to the growth of particles.However, by removing coarse particles in advance, this effect can be eliminated and efficient flotation processing can be performed. it can. The coarse particles of coal ash are preferably classified by wind (air) so that the residual value on the 88 μm sieve is 3% by weight or less. That is, coal ash whose coal ash particle residual value on a 88 μm sieve is 3% by weight or less is subjected to flotation treatment by air classification. If this exceeds 3% by weight, the above-mentioned effect is lost and the unburnt coal removal rate cannot be increased.
[0009]
Next, heavy oil, kerosene and the like as a collector used in the hydrophobizing step, and conventionally known substances such as pine oil as a foaming agent used in the flotation step can be used. An emulsifier obtained by mixing a sex collector alone or with a nonpolar reagent can be suitably used. Examples of the ionic scavenger include alkylamine, alkylammonium, xanthate, oleic acid, alkylsulfate, alkylsulfonate and the like.Alkylamine and alkylsulfonate are extremely excellent in hydrophobizing unburned carbon. It can be suitably used as a sex collector. Kerosene, xylene, cyclohexane, decane and the like are preferably used as the nonpolar reagent. As the emulsification, any method such as stirring or shaking may be used, in addition to applying ultrasonic waves to a mixture of the ionic collector and the nonpolar reagent.
[0010]
[Action]
When adding a trapping agent to the coal ash slurry to hydrophobize the unburned coal content, add a foaming agent to the water slurry to generate air bubbles, and attach the unburned coal content to the surface of the air bubbles to raise them. The coal ash was air-classified in advance so that the residual value on the 88 μm sieve was 3% by weight or less, and the coal ash from which coarse particles were removed , that is, the residual value on the 88 μm sieve of the coal ash particles was 3% by weight or less. By using coal ash, the unburned coal content is easily increased.
[0011]
【Example】
Example 1
Coal ash having an Ig-Loss (loss on ignition) of the raw powder of 9.0% by weight (hereinafter% indicates each% by weight) and a residue of 88% on a sieve of 6.1% was classified into an air classifier (accu). Classification was performed by changing the classification point with Cut A-12 (manufactured by Nippon Donaldson Co., Ltd.), and the residual values of 88 μm from which coarse particles were removed were 2.6%, 2.3%, and 1.5%, respectively. Was obtained (classification process). 80 g of each of the raw powder and the classified coal ash and 800 ml of water were mixed with stirring in a flotation tank to form a water slurry, and 2.0 ml of a petroleum sulfone aqueous solution (concentration: 1.0% by weight) was collected as a collecting agent. The mixture is added and left for 3 minutes with stirring to hydrophobize the unburned coal in the coal ash (hydrophobizing step). After the hydrophobization step, 60 mg of pine oil is added to the water slurry as a foaming agent, and air is blown from the bottom of the flotation tank to generate air bubbles, and unburned coal is attached to the air bubbles and floated. The floating bubbles are taken out as an overflow. This step was continuously performed for 3 minutes (flotation step). Next, the Ig-Loss of the coal ash from which the overflow was removed was measured.
[0012]
FIG. 1 shows the relationship between the Ig-Loss of the coal ash subjected to the flotation treatment and the residual value of 88 μm. As can be seen from the figure, the Ig-Loss after the treatment is reduced by lowering the classification point and lowering the 88 μm residue. However, if 88 μm is reduced to a certain degree or more, Ig-Loss does not decrease after further processing. It is considered that this is because only particles having a certain size or more affect the flotation process.
[0013]
Example 2
Classification of three types of coal ash (raw powder) having different Ig-Loss by an air classifier (Acucut A-12: Nippon Donaldson) under the same conditions (air amount, blade rotation speed, raw material supply speed constant). , Coarse particles were removed. Table 1 shows the results. Since unburned coal is present in large amounts on the coarse particle side, Ig-Loss is slightly reduced by classification.
[0014]
[Table 1]
Next, 80 g of each of the raw powder and the classified coal ash and 800 ml of water were mixed with stirring in a flotation tank to form a water slurry, and an aqueous solution of a petroleum sulfone agent (concentration: 1.0% by weight) was collected as a collector. Then, it was left for 3 minutes while stirring (hydrophobizing step). Thereby, the unburned coal content in the coal ash is made hydrophobic. After the hydrophobizing step, 60 mg of pine oil was added as a foaming agent to the water slurry, air was blown from the bottom of the flotation tank to generate bubbles, and unburned coal was attached to the bubbles and floated (flotation step) ). Next, the Ig-Loss of the coal ash from which the overflow was removed was measured.
[0016]
FIG. 2 shows the unburned coal removal rate when the above-mentioned flotation treatment was performed with the classified coal ash in comparison with the result of performing the flotation treatment with the raw powder without performing the classification treatment. The unburned coal removal rate is obtained by dividing Ig-Loss before the flotation treatment by Ig-Loss after the treatment, and the higher the value, the greater the treatment effect. From this, it was found that even if the treatment was performed using coal ash having different Ig-Loss, the unburned coal removal rate was increased by performing the classification treatment.
[0017]
Effect of the Invention]
The present invention relates to coal ash obtained by air classification of coal ash to remove coarse particles so that the 88 μm sieve residue value is 3% by weight or less. By performing the flotation treatment using the coal ash having a weight percent or less, the unburned coal content of the coal ash can be efficiently removed.
[Brief description of the drawings]
FIG. 1 is a graph showing the relationship between the residual value of 88 μm and the Ig-Loss of coal ash subjected to flotation processing in Example 1.
FIG. 2 is a graph showing a removal rate of unburned coal by flotation treatment of classified coal ash and unclassified coal ash in Example 2.
Claims (1)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21658994A JP3580868B2 (en) | 1994-08-18 | 1994-08-18 | Coal ash treatment method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP21658994A JP3580868B2 (en) | 1994-08-18 | 1994-08-18 | Coal ash treatment method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0857351A JPH0857351A (en) | 1996-03-05 |
| JP3580868B2 true JP3580868B2 (en) | 2004-10-27 |
Family
ID=16690794
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP21658994A Expired - Fee Related JP3580868B2 (en) | 1994-08-18 | 1994-08-18 | Coal ash treatment method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3580868B2 (en) |
Families Citing this family (14)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3613347B1 (en) | 2003-10-09 | 2005-01-26 | 太平洋セメント株式会社 | How to remove unburned carbon in fly ash |
| JP2005334819A (en) * | 2004-05-28 | 2005-12-08 | Osaka Prefecture | Method for recycling shredder dust by wet classification method |
| JP2007054773A (en) * | 2005-08-26 | 2007-03-08 | Mitsui Eng & Shipbuild Co Ltd | Unburned carbon removal method in coal ash |
| WO2007023937A1 (en) | 2005-08-26 | 2007-03-01 | Taiheiyo Cement Corporation | Apparatus and method for dissolution/reaction |
| US8282263B2 (en) | 2005-10-31 | 2012-10-09 | Taiheiyo Cement Corporation | Apparatus and method for adding wet ash to cement |
| CN101326011B (en) * | 2005-12-07 | 2013-02-27 | 太平洋水泥株式会社 | Apparatus for removing of unburned carbon from fly ash and relevant removing method |
| JP4917309B2 (en) * | 2005-12-26 | 2012-04-18 | 三井造船株式会社 | How to remove unburned carbon in fly ash |
| JP2007222800A (en) * | 2006-02-24 | 2007-09-06 | Taiheiyo Cement Corp | Apparatus and method for removing unburnt carbon in fly ash |
| CN100391574C (en) * | 2006-04-25 | 2008-06-04 | 开滦精煤股份有限公司范各庄矿业分公司 | Process for dehydrating floatation coal |
| CN101528953B (en) | 2006-10-24 | 2011-10-19 | 太平洋水泥株式会社 | Method for removing lead from cement kiln |
| CN101583578A (en) | 2006-12-05 | 2009-11-18 | 太平洋水泥株式会社 | Method of processing coal ash and processing system |
| EP2103361A1 (en) * | 2006-12-11 | 2009-09-23 | Mitsui Engineering and Shipbuilding Co, Ltd. | Method of removing unburned carbon from coal ash |
| CN110766673B (en) * | 2019-07-22 | 2021-04-30 | 中南大学 | Texture roughness defining method based on Euclidean distance judgment |
| CN110728253B (en) * | 2019-07-22 | 2021-03-02 | 中南大学 | Texture feature measurement method based on particle roughness |
-
1994
- 1994-08-18 JP JP21658994A patent/JP3580868B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0857351A (en) | 1996-03-05 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP3580868B2 (en) | Coal ash treatment method | |
| JP3613347B1 (en) | How to remove unburned carbon in fly ash | |
| CN102834181B (en) | Cleaning and dewatering fine coal | |
| JP5326168B2 (en) | A method for treating coal ash used in concrete materials. | |
| JP2007054773A (en) | Unburned carbon removal method in coal ash | |
| TWI362966B (en) | Method of removing unburned carbon from fly ash | |
| US4226672A (en) | Process of separating asbestos fibers and product thereof | |
| TW201029743A (en) | Method for removing unburned carbon from fly ash and equipment for removing unburned carbon from fly ash | |
| JPS59127660A (en) | Treatment of coal ash and low grade coal | |
| JP3581707B2 (en) | Coal ash treatment method | |
| JP3243568B2 (en) | Processing method of coal ash | |
| JP3505000B2 (en) | Coal ash treatment method | |
| JP2003284973A (en) | Method for treating coal ash | |
| WO1998024733A1 (en) | Wet process fly ash beneficiation | |
| CN112958275A (en) | Method for flotation of coal from coal-containing casting dust | |
| TWI499456B (en) | Method for upgrading combustion ash | |
| JP3411649B2 (en) | Processing method of coal ash | |
| JP3411651B2 (en) | Processing method of coal ash | |
| JPH06256014A (en) | Production of high-purity white gypsum | |
| JP2009091189A (en) | Method and apparatus for treating gypsum board and fly ash | |
| US3259243A (en) | Silicon carbide recovery | |
| JP4346043B1 (en) | Method for producing recycled concrete material and recycled concrete material | |
| JPH06256015A (en) | Method for removing dust from gypsum slurry | |
| JP2022056672A (en) | Determination method of production condition of modified fly ash and production method | |
| JP2010227769A (en) | Device for manufacturing modified ash and method of manufacturing modified ash |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20040204 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20040316 |
|
| A521 | Written amendment |
Free format text: JAPANESE INTERMEDIATE CODE: A523 Effective date: 20040513 |
|
| TRDD | Decision of grant or rejection written | ||
| A01 | Written decision to grant a patent or to grant a registration (utility model) |
Free format text: JAPANESE INTERMEDIATE CODE: A01 Effective date: 20040706 |
|
| A61 | First payment of annual fees (during grant procedure) |
Free format text: JAPANESE INTERMEDIATE CODE: A61 Effective date: 20040721 |
|
| R150 | Certificate of patent or registration of utility model |
Free format text: JAPANESE INTERMEDIATE CODE: R150 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20070730 Year of fee payment: 3 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20080730 Year of fee payment: 4 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20090730 Year of fee payment: 5 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100730 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100730 Year of fee payment: 6 |
|
| S531 | Written request for registration of change of domicile |
Free format text: JAPANESE INTERMEDIATE CODE: R313531 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100730 Year of fee payment: 6 |
|
| R350 | Written notification of registration of transfer |
Free format text: JAPANESE INTERMEDIATE CODE: R350 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20100730 Year of fee payment: 6 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20110730 Year of fee payment: 7 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20120730 Year of fee payment: 8 |
|
| FPAY | Renewal fee payment (event date is renewal date of database) |
Free format text: PAYMENT UNTIL: 20130730 Year of fee payment: 9 |
|
| LAPS | Cancellation because of no payment of annual fees |