JPH0741762A - Coal-ash-containing particle and its use - Google Patents

Coal-ash-containing particle and its use

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Publication number
JPH0741762A
JPH0741762A JP3240185A JP24018591A JPH0741762A JP H0741762 A JPH0741762 A JP H0741762A JP 3240185 A JP3240185 A JP 3240185A JP 24018591 A JP24018591 A JP 24018591A JP H0741762 A JPH0741762 A JP H0741762A
Authority
JP
Japan
Prior art keywords
water
soil
ash
coal
coal 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.)
Pending
Application number
JP3240185A
Other languages
Japanese (ja)
Inventor
Yasuhiko Kato
安彦 加藤
Akira Tsuruta
暁 鶴田
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
KANKYO TECHNOS KK
Original Assignee
KANKYO TECHNOS KK
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by KANKYO TECHNOS KK filed Critical KANKYO TECHNOS KK
Priority to JP3240185A priority Critical patent/JPH0741762A/en
Publication of JPH0741762A publication Critical patent/JPH0741762A/en
Pending legal-status Critical Current

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  • Soil Conditioners And Soil-Stabilizing Materials (AREA)
  • Processing Of Solid Wastes (AREA)
  • Glanulating (AREA)
  • Solid-Sorbent Or Filter-Aiding Compositions (AREA)

Abstract

PURPOSE:To provide coal-ash-containing particles which can be used as a soil additive which is mixed with soil of e.g. golf links to assist the soil in adsorbing and holding an agricultural chemical or a fertilizer by using coal ash produced in large quantities from a thermal power plant. CONSTITUTION:A water-containing particle containing coal ash as a principal solid component and desirably a synthetic zeolite or cement, and its use as a soil additive are provided. The water content of the above particles is about 10-27wt.%.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は含水粒状物およびその用
途に関する。更に詳しくは、石炭火力発電所等から大量
に発生する石炭灰を固形主成分とする含水粒状物および
その土壌添加材としての用途に関する。
FIELD OF THE INVENTION This invention relates to hydrous granules and their uses. More specifically, the present invention relates to a water-containing granular material containing a large amount of coal ash generated from a coal-fired power plant or the like as a solid main component and its use as a soil additive.

【0002】[0002]

【従来の技術】石炭火力発電所は従来からの微粉炭燃焼
法と、NOxSOxの低減及び熱効率が良好なために主
力となって稼働し始め、今後も建設が計画されている流
動床法とがある。
2. Description of the Related Art A coal-fired power plant has a conventional pulverized coal combustion method and a fluidized bed method which has started to operate as a main force due to its low NOxSOx and good thermal efficiency and is planned to be constructed in the future. is there.

【0003】前者は高温燃焼されているので未燃炭素の
残留が少なく、JISA6201に合格するものはフラ
イアッシュセメント等の混和材として利用されている
が、粗粒部分の一部がセメント原料に利用されているの
みで、殆どは埋立廃棄処分されている。又、後者の流動
床法からの発生灰は低温燃焼のため、未燃炭成分が10
〜25wt%と多く、フライアッシュセメントには使用
できず、ごく一部がセメント原料に使用されるのみで、
その大部分は埋立廃棄されている。
Since the former is burned at a high temperature, there is little residual unburned carbon, and those which pass JIS A6201 are used as admixtures such as fly ash cement, but part of the coarse particles are used as a cement raw material. Most of them are landfilled. In addition, the ash generated from the latter fluidized bed method is low-temperature combustion, so the unburned carbon component is 10%.
As much as ~ 25wt%, it cannot be used for fly ash cement, and only a small portion is used as a cement raw material.
Most of them are landfilled.

【0004】この様な石炭灰を更に有効利用しようとす
る試みもなされ、石炭灰にバインダーとして粘土粉を配
合して造粒後焼成し、軽量骨材を製造することも一部実
施されている。又、石炭灰(フライアッシュ、クリンカ
−アッシュ)をアルカリ水溶液中で加熱結晶化させる合
成ゼオライトの製造方法、その金属陽イオンの吸着剤、
アンモニア等の吸着脱臭剤等への利用方法も提案されて
いる(特開昭61−178416,昭61−17494
5,昭62−132580,昭63−182214
等)。しかしこれらも有効利用のごく一部に過ぎず、大
部分は未使用のまま埋立廃棄されているのが現状であ
る。
Attempts have been made to utilize such coal ash more effectively, and it has been partially carried out to mix the coal ash with a clay powder as a binder, granulate it and then burn it to produce a lightweight aggregate. . Further, a method for producing a synthetic zeolite, in which coal ash (fly ash, clinker ash) is heated and crystallized in an alkaline aqueous solution, an adsorbent for its metal cation,
A method for utilizing ammonia as an adsorption deodorant or the like has also been proposed (Japanese Patent Laid-Open No. 61-178416, 61-174494).
5, Sho 62-132580, Sho 63-182214
etc). However, these are only a small part of effective use, and most of them are currently landfilled unused.

【0005】[0005]

【発明が解決しようとする課題】エネルギー調査会の長
期見通しでは、今後とも石炭火力発電所が増加し、それ
に伴い石炭灰の発生量も増加が見込まれ、埋立廃棄場所
の確保が問題視されている。そして、埋立以外の用途開
発が急務となっている。
[Problems to be Solved by the Invention] According to the long-term outlook of the Energy Investigation Committee, the number of coal-fired power plants will continue to increase and the amount of coal ash generated is expected to increase accordingly, and securing a landfill disposal site is a problem. There is. There is an urgent need to develop applications other than landfill.

【0006】[0006]

【課題を解決するための手段】本発明者等は石炭灰の有
効利用に関する上記現状に鑑み、鋭意検討した結果、石
炭灰を固形主成分とする高含水率の粒状物が新規であ
り、かつ該粒状物が土壌添加材、とりわけゴルフ場での
農薬、肥料の散布に伴う公害問題に対処可能な吸着剤、
更には保水材として極めて優れたものであることを見出
し、本発明を完成するに至った。
Means for Solving the Problems The inventors of the present invention have made diligent studies in view of the above-mentioned current state of effective utilization of coal ash, and as a result, have found that a high water content granular material containing coal ash as a solid main component is novel, and The particulate matter is a soil additive, especially an adsorbent capable of coping with pollution problems associated with spraying pesticides and fertilizers on golf courses,
Furthermore, they have found that they are extremely excellent as water retaining materials, and have completed the present invention.

【0007】すなわち、本発明は石炭灰を固形主成分と
する含水粒状物および該粒状物からなる土壌添加材に関
する。
That is, the present invention relates to a water-containing granular material containing coal ash as a solid main component and a soil additive comprising the granular material.

【0008】なお該含水粒状物には、石炭灰以外の成分
として、合成ゼオライトまたはセメント成分を含有する
ことが好ましい。
The water-containing granular material preferably contains a synthetic zeolite or cement component as a component other than coal ash.

【0009】以下、本発明を詳しく説明する。The present invention will be described in detail below.

【0010】本発明の含水粒状物は、石炭灰を固形主成
分とするものである。石炭灰としてはフライアッシュ、
クリンカーアッシュ(ボトムアッシュ)、単一の石炭燃
焼灰などを用いることが出来るが、未燃炭素分が10〜
30wt%含まれているものを用いることが好ましい。
The water-containing granular material of the present invention contains coal ash as a solid main component. Fly ash as coal ash,
Clinker ash (bottom ash), single coal combustion ash, etc. can be used, but unburned carbon content is 10
It is preferable to use the one containing 30 wt%.

【0011】石炭灰は常法により平均粒径約50μm以
下に粉砕し、かつ乾燥したものを用いることが好まし
い。
It is preferable to use the coal ash which has been crushed to an average particle size of about 50 μm or less by a conventional method and dried.

【0012】本発明の粒状物を構成する固形成分として
は、石炭灰のみであっても構わないが、土壌添加材とし
ての効果を高めるため、合成ゼオライト、木炭粉、活性
炭粉、スラグ粉、粘土粉、セメントの群から選ばれる一
種又は二種以上の成分を含むことが好ましい。特に合成
ゼオライトは土壌中での吸着能力を高め、またセメント
成分は含水粒状物の形状を保持する観点から、本発明の
含水粒状物に含まれることが好ましい。
As the solid component constituting the granular material of the present invention, only coal ash may be used, but synthetic zeolite, charcoal powder, activated carbon powder, slag powder, clay are used in order to enhance the effect as a soil additive. It is preferable to contain one or more components selected from the group of powder and cement. In particular, it is preferable that the synthetic zeolite is contained in the hydrous granules of the present invention from the viewpoint of enhancing the adsorption capacity in soil and maintaining the shape of the hydrous granules.

【0013】なお合成ゼオライトは常法により、未燃炭
素分を含有する石炭灰は約700℃で仮焼し、未燃炭素
分を除去した後、アルカリ溶液中で処理し、水洗、乾燥
したP型ゼオライトもしくはヒドロキシソーダライト、
もしくは両者の混合物が好ましい。
The synthetic zeolite is prepared by a conventional method. Coal ash containing unburned carbon is calcined at about 700 ° C. to remove unburned carbon, and then treated in an alkaline solution, washed with water and dried. Type zeolite or hydroxy sodalite,
Alternatively, a mixture of both is preferable.

【0014】また、セメント類とは市販のポルトランド
セメント系(普通、早強、超早強、フライアッシュ、高
炉、シリカ)セメント、アルミナセメント、軟弱地盤等
の硬化剤を指す。
The cements are commercially available hardeners such as Portland cement-based (normal, early strength, ultra-fast strength, fly ash, blast furnace, silica) cement, alumina cement, and soft ground.

【0015】各成分の好ましい配合割合としては、石炭
灰75〜95wt%、合成ゼオライト5〜20wt%、
セメント2〜20wt%、とくに好ましくは3〜8wt
%、その他の成分はそれぞれ5〜20wt%、とくには
5〜10wt%の範囲である。
The preferred blending ratio of each component is 75 to 95 wt% of coal ash, 5 to 20 wt% of synthetic zeolite,
Cement 2 to 20 wt%, particularly preferably 3 to 8 wt
%, Other components are in the range of 5 to 20 wt%, and particularly 5 to 10 wt%.

【0016】本発明の含水粒状物を製造するには、各配
合成分を混合し、散水しながら平均粒径約2〜5mm以
下、とくに好ましくは0.3〜1mmに造粒し、造粒後
も常温空気中で時々散水しながら養生させる。例えば造
粒24時間後、表面が乾燥し始める毎に時々スプリンク
ラー等で散水しながら常温空気中で14〜30時間程度
養生させる。成分の混合、造粒にはヘンシェルミキサ
ー、オムミキサー、パン型ペレタイザー等常用手段を用
いることが出来る。造粒の別の方法としては、成形機或
は団鉱機を用い、各成分を含有するブロック状或は豆炭
状の含水成形物を得、必要に応じて散水しながら養生さ
せたのち、上記粒径範囲に粗砕してもよい。造粒後に養
生させる場合は造粒成形の約12時間経過後、約5〜6
時間蒸気養生(約70〜75℃)させる。
In order to produce the water-containing granular material of the present invention, the respective components are mixed and granulated to have an average particle size of about 2 to 5 mm or less, particularly preferably 0.3 to 1 mm, and then granulated. Even at room temperature, sprinkle water occasionally to cure. For example, after 24 hours of granulation, each time the surface begins to dry, it is aged for about 14 to 30 hours in normal temperature air with occasional sprinkler spraying. For mixing and granulating the components, a conventional means such as a Henschel mixer, an OM mixer or a pan type pelletizer can be used. As another method of granulating, using a molding machine or a briquetting machine, a block-shaped or bean-coal-shaped water-containing molded article containing each component is obtained, and after curing with watering if necessary, the above It may be crushed to a particle size range. When curing after granulation, about 5 to 6 after about 12 hours of granulation molding
Steam cure (about 70 to 75 ° C.) for an hour.

【0017】このようにして得られる含水粒状物の含水
率は、通常10〜27wt%、好ましくは15〜25w
t%である。
The water content of the water-containing granular material thus obtained is usually 10 to 27 wt%, preferably 15 to 25 w.
t%.

【0018】石炭灰を固形主成分とする前記含水粒状物
は、土壌添加材として極めて有用である。近年ゴルフ場
開発が進むにつれ、ゴルフ場で使用される除草剤、殺虫
剤、殺菌剤などの農薬あるいは肥料が周囲の田畑や河川
を汚染し、環境問題を起こしているが、前記含水粒状物
をゴルフ場の土壌に添加することにより、農薬等のゴル
フ場からの流出を有効的に防止することが出来る。これ
は、該含水粒状物が多孔質であり、農薬成分の吸着能が
著しく高められていることによるものと考えられる。土
壌への添加量は農薬等の施用量等によっても異なるが、
ゴルフ場造成に使用される土砂の5〜15%程度とする
ことが好ましい。
The water-containing granular material containing coal ash as a solid main component is extremely useful as a soil additive. With the recent progress in golf course development, herbicides, pesticides, and fungicides such as pesticides and fertilizers used in golf courses pollute the surrounding fields and rivers, causing environmental problems. By adding it to the soil of the golf course, it is possible to effectively prevent the outflow of agricultural chemicals from the golf course. It is considered that this is because the water-containing granules are porous and the adsorbability of pesticide components is remarkably enhanced. The amount added to the soil will vary depending on the amount of pesticide applied, etc.
It is preferably about 5 to 15% of the earth and sand used for golf course construction.

【0019】また該含水粒状物は前記のように肥料成分
を良く吸着保持するので、肥料の保持材としての土壌に
添加することも有効である。肥料はあらかじめ含水粒状
物に保持させたのちに土壌に添加してもよい。
Further, since the water-containing granular material well adsorbs and holds the fertilizer component as described above, it is also effective to add it to the soil as a fertilizer holding material. The fertilizer may be added to the soil after being held in the water-containing granular material in advance.

【0020】更に該含水粒状物は水分を多く含んでいる
ので、保水材として土壌に添加できる。これはとくに乾
燥土壌の保水に有効である。なお該含水粒状物自体を人
工土壌として植物育成に用いることも土壌添加材として
の本発明の一態様に含まれる。
Furthermore, since the water-containing granular material contains a large amount of water, it can be added to the soil as a water retaining material. This is especially effective for retaining water in dry soil. The use of the water-containing granular material itself as artificial soil for growing plants is also included in one aspect of the present invention as a soil additive.

【0021】[0021]

【実施例】以下、本発明を実施例により具体的に説明す
る。
EXAMPLES The present invention will be specifically described below with reference to examples.

【0022】(実施例1〜5)石炭灰、合成ゼオライ
ト、木炭、活性炭、スラグ、粘土およびセメントを表1
に示す割合でパッグミルを用いて混合し、散水しながら
パン型ペレタイザーを用いて造粒し、空気中で24時間
後に時々散水しながら15〜30日間養生した。得られ
た造粒物の表乾比重(JISA1110)、含水率(J
ISA1109)、嵩比重(JISA1104)を表1
に示した。
(Examples 1 to 5) Coal ash, synthetic zeolite, charcoal, activated carbon, slag, clay and cement are shown in Table 1.
The mixture was mixed with a pagg mill at the ratio shown in Table 1, granulated using a pan-type pelletizer while water was sprinkled, and cured for 15 to 30 days in the air with occasional water sprinkling after 24 hours. Surface dry specific gravity (JIS A1110) and water content (J
ISA1109) and bulk specific gravity (JIS A1104) are shown in Table 1.
It was shown to.

【0023】なお原料に用いた石炭灰、粘土、スラグの
化学分析値等を表2に示す。また、セメントは市販品
を、合成ゼオライトは未燃炭素分を含有する石炭灰にあ
っては約700℃で仮焼し、未燃炭素分を除去した後ア
ルカリ溶液(NaOH、1N以上)中97〜98℃で1
2時間処理して、水洗、乾燥(105〜110℃)した
P型ゼオライトもしくはヒドロキシソーダライトもしく
は両者の混合物である。
Table 2 shows chemical analysis values of coal ash, clay, and slag used as raw materials. In addition, cement is a commercially available product, and synthetic zeolite is coal ash containing unburned carbon, which is calcined at about 700 ° C. to remove unburned carbon, and then 97 in an alkaline solution (NaOH, 1N or more). 1 at ~ 98 ° C
It is a P-type zeolite or hydroxysodalite or a mixture of both that has been treated for 2 hours, washed with water and dried (105 to 110 ° C.).

【0024】更に、石炭灰、合成ゼオライト以外はジョ
ークラッシャー等で粗砕して乾燥(105〜110℃)
し、バイブロミル等で粒径約44μm以下に粉砕して原
料とした。
Further, except for coal ash and synthetic zeolite, it is roughly crushed with a jaw crusher and dried (105 to 110 ° C.).
Then, it was pulverized with a vibromill or the like to have a particle size of about 44 μm or less to obtain a raw material.

【0025】[0025]

【表1】 [Table 1]

【0026】[0026]

【表2】 [Table 2]

【0027】(実施例6〜7、比較例1)前記実施例1
〜2で得られた粒状物の農薬吸着性を確認するために、
カラムに充填した粒状物(最下層に5Cのろ紙を一枚敷
き、その上に造粒物を充填)に、上部から殺菌剤、殺虫
剤、除草剤を通常の施用量散布し、3時間および7日間
経過後、各々20mmの雨量相当の散水を行い、カラム
の下部から流出する水について農薬含有量を分析した。
なお、比較のために、砂のみを使用した場合についても
同様の実験を行った。これらの結果を表3に示す。
(Examples 6 to 7 and Comparative Example 1) The above Example 1
In order to confirm the pesticide adsorption of the granular material obtained in ~ 2,
The granules packed in the column (laying a piece of 5C filter paper on the bottom layer and filling the granules on top of it) are sprayed with fungicides, insecticides, and herbicides from the top, and the usual application rate is applied for 3 hours and After 7 days, water was sprinkled for each 20 mm of rainfall, and the pesticide content of the water flowing out from the lower part of the column was analyzed.
For comparison, the same experiment was carried out when sand alone was used. The results are shown in Table 3.

【0028】[0028]

【表3】 [Table 3]

【0029】表3より、本発明の含水粒状物層を設ける
ことによって、ゴルフ場の芝下の土層中に流入した農薬
等を粒状物層に吸着させ、環境汚染を防除することので
きることが分かる。又、粒状物は含水率が大きいので植
物に必要な水分や肥料を保持することもできる。
From Table 3, it can be seen that by providing the water-containing granular material layer of the present invention, pesticides and the like that have flowed into the soil layer under the grass of a golf course can be adsorbed to the granular material layer to prevent environmental pollution. I understand. Further, since the granular material has a high water content, it is possible to retain water and fertilizer necessary for the plant.

【0030】又、ペレット層を形成する造粒物は、石炭
灰単味よりも合成ゼオライトを配合した造粒物のほうが
良好な結果を与える。
As for the granulated product forming the pellet layer, the granulated product containing the synthetic zeolite gives better results than the coal ash alone.

【0031】[0031]

【発明の効果】以上で述べた様に、本発明によれば石炭
火力発電所から大量に排出され、一部を除いては埋立廃
棄処分されている産業廃棄物の石炭灰、及び石炭灰をア
ルカリ水溶液中で加熱結晶化させた合成ゼオライト等を
主体にして含水粒状物とし、ゴルフ場、公園、芝地、緑
地等の土壌に添加して、農薬や肥料を吸着、保持させる
土壌添加材として有効利用するものである。
Industrial Applicability As described above, according to the present invention, the coal ash of industrial waste that is discharged from a coal-fired power plant in a large amount and is partially landfilled, and coal ash, is used. As a water-containing granular material mainly composed of synthetic zeolite heated and crystallized in an alkaline aqueous solution, and added to the soil of golf courses, parks, lawns, green areas, etc. as a soil additive to adsorb and retain pesticides and fertilizers It is used effectively.

フロントページの続き (51)Int.Cl.6 識別記号 庁内整理番号 FI 技術表示箇所 B09B 3/00 ZAB C09K 17/10 H 9451−4H // C09K 101:00 Continuation of front page (51) Int.Cl. 6 Identification number Office reference number FI technical display location B09B 3/00 ZAB C09K 17/10 H 9451-4H // C09K 101: 00

Claims (4)

【特許請求の範囲】[Claims] 【請求項1】石炭灰を固形主成分とする含水粒状物。1. A water-containing granular material containing coal ash as a main solid component. 【請求項2】合成ゼオライトまたはセメントを含有する
請求項1記載の含水粒状物。
2. The water-containing granular material according to claim 1, which contains synthetic zeolite or cement.
【請求項3】石炭灰を固形主成分とする含水粒状物から
なる土壌添加材。
3. A soil additive comprising a water-containing granular material having coal ash as a solid main component.
【請求項4】合成ゼオライトまたはセメントを含有する
含水粒状物からなる請求項3記載の土壌添加材。
4. The soil additive as claimed in claim 3, which comprises a hydrous granular material containing synthetic zeolite or cement.
JP3240185A 1991-08-28 1991-08-28 Coal-ash-containing particle and its use Pending JPH0741762A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3240185A JPH0741762A (en) 1991-08-28 1991-08-28 Coal-ash-containing particle and its use

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3240185A JPH0741762A (en) 1991-08-28 1991-08-28 Coal-ash-containing particle and its use

Publications (1)

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JPH0741762A true JPH0741762A (en) 1995-02-10

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JP3240185A Pending JPH0741762A (en) 1991-08-28 1991-08-28 Coal-ash-containing particle and its use

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011173100A (en) * 2010-02-25 2011-09-08 Chugoku Electric Power Co Inc:The Granular material for water purification and water purification method
JP2013176314A (en) * 2012-02-28 2013-09-09 Japan Research Institute Ltd Mulching sheet material and method of laying the same
JP2018158340A (en) * 2017-03-23 2018-10-11 中国電力株式会社 Coal ash granule and method for producing coal ash granule

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2011173100A (en) * 2010-02-25 2011-09-08 Chugoku Electric Power Co Inc:The Granular material for water purification and water purification method
JP2013176314A (en) * 2012-02-28 2013-09-09 Japan Research Institute Ltd Mulching sheet material and method of laying the same
JP2018158340A (en) * 2017-03-23 2018-10-11 中国電力株式会社 Coal ash granule and method for producing coal ash granule

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