JP2004123425A - Inorganic foam, its composition and manufacturing process - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inorganic foam composition which recycles wastes and stably yields an inorganic foam having a desired specific gravity and an excellent water quality improvement effect, the inorganic foam wherein layers with different specific gravity are laminated and unified, and a highly energy-saving process for manufacturing the inorganic foam which requires little facility load such as a heating furnace and performs secure foaming and bubble formation with stable quality. <P>SOLUTION: The inorganic foam composition contains an inorganic powder obtained by pulverizing inorganic scraps and a shell powder obtained by pulverizing shells. <P>COPYRIGHT: (C)2004,JPO

Description

（表１）に示す測定方法において、「ＪＫ０１０２」と表示されているものは「ＪＩＳ　Ｋ　０１０２」の略であり、「Ｓ４９環告」と表示されているものは「昭和４９年環境庁告示」の略であり、「Ｓ４６環告」と表示されているものは「昭和４６年環境庁告示」の略である。
この結果、本実施例の無機系発泡体によれば、有害物質の溶出はみられないことが明らかになった。
【００４９】
（水質改善用浄化担体としての評価）
実施例１，２及び比較例１の無機系発泡体を用いて、水質改善用浄化材としての評価を行った。
図４は水質改善用浄化材の評価試験装置の模式図である。
図４において、１０は水質改善用浄化材の評価試験装置、１１は容量１００ｍｌのカラム、１２は一辺が約１ｃｍの略立方体状に切断若しくは破砕されカラム１１内に充填された実施例１，２等の試料である無機系発泡体、１３は容量約１リットルのビーカー、１４は０．４ｍｇ／Ｌのアンモニア性窒素と０．２ｍｇ／Ｌのリン酸態リンとを含有しビーカー１３に注入された約１リットルの水溶液、１５はカラム１１の下流側とビーカー１３に接続されカラム１１を通過した水溶液１４をビーカー１３に供給する液体循環路、１６はビーカー１３とカラム１１の上流側に接続されビーカー１３内の水溶液１４をカラム１１に供給する液体循環路、１７は液体循環路１６に配設され水溶液１４を循環するローラーチューブポンプ等のポンプである。
本評価試験では、容量が１００ｍｌのカラム１１内に充填した略同一容積の無機系発泡体１２の水質浄化性能について評価した。なお、無機系発泡体１２は、一辺が約１ｃｍの略立方体状に切断若しくは破砕した後、常温の室内で１０日間自然乾燥したものを用い、カラム１１内に充填した。充填量は、実施例１の無機系発泡体では２５．５ｇ、実施例２の無機系発泡体では５０．２ｇ、比較例１の無機系発泡体では２０．１ｇであった。また、カラム１１を通過する水溶液１４の流量が２００ｍｌ／ｈになるようにポンプ１７を調整した。なお、アンモニア性窒素を０．４ｍｇ／Ｌ、リン酸態リンを０．２ｍｇ／Ｌとしたのは、汚濁負荷がかなり大きな河川を想定したからである。
【００５０】
以上のように構成された評価試験装置１０を用いてポンプ１７を駆動して実験を開始した後、０，１，３，５，１２，２４，４８時間後の水溶液１４をビーカー１３から採取し、採取した水溶液についてアンモニア性窒素とリン酸態リンの測定を行った。
その結果を、図５及び図６に示す。
図５は実験開始からの経過時間とアンモニア性窒素の比濃度との関係を示す図であり、図６は実験開始からの経過時間とリン酸態リンの比濃度との関係を示す図である。ここで、比濃度とは、実験開始前（経過時間０）のアンモニア性窒素等の濃度を１としたときの各経過時間におけるアンモニア性窒素等の濃度との比を示したものである。
【００５１】
図５に示すように、貝殻粉体を用いた実施例１及び実施例２の無機系発泡体は、試験開始から約４８時間でアンモニア性窒素の比濃度を０．２以下の低濃度にすることができた。このことからアンモニア性窒素については、貝殻粉体を用いた実施例１及び実施例２の無機系発泡体は、炭化珪素を用いた比較例１の無機系発泡体とほぼ同様の水質改善作用を示すことが明らかになった。
【００５２】
次に、リン酸態リンについては、図６に示すように、実施例１の無機系発泡体で実験開始から４８時間で比濃度を０．４以下にすることができた。一方、比較例１の無機系発泡体では、実験開始から４８時間で比濃度は０．７程度であった。
このことは、無機系発泡体の破壊面から貝殻が含有するカルシウム、マグネシウムが水中に溶出することにより、リン酸態リンがリン酸カルシウム（不溶性）になり、水質の改善が行われるものであると推察している。実施例１の無機系発泡体のリン酸態リンの除去能力が、実施例２の無機系発泡体より高いのは、実施例１の無機系発泡体に用いられた貝殻粉体の粒径が０．１〜１０００μｍと大きいため、発泡後に基体内に残留した貝殻粉体の量が多いからであると推察している。
以上のように本実施例によれば、アンモニア性窒素及びリン酸態リンの除去効果に優れるとともに有害物質の溶出がみられない水質改善用浄化材として最適の無機系発泡体が得られることが明らかになった。
【００５３】
（実施例３）
実施例１と同様にして形成した粒径が０．１〜１０００μｍの無機系粉体１００重量部に粒径が０．１〜３０００μｍに形成された貝殻粉体を１１重量部添加混合した混合粉体を作成し、メッシュベルト上に約７ｍｍの厚さで堆積した。
次いで、実施例１と同様に設定された加熱炉で加熱し溶融発泡させ、実施例３の無機系発泡体を得た。
実施例３の無機系発泡体の比重を測定したところ、１．１ｇ／ｃｍ^３であった。これを水に浸漬すると沈むことが確認された。破断面を観察したところ、内径０．２〜３ｍｍの気泡が分布していることが確認された。
【００５４】
（実施例４）
実施例１と同様にして形成した粒径が０．１〜１０００μｍの無機系粉体１００重量部に粒径が０．１〜２０μｍに形成された大理石等から形成された炭酸カルシウム等の石粉を４重量部添加混合したものを作成し、メッシュベルト上に堆積し厚み約７ｍｍの高比重粉体層を形成した。
次に、実施例１と同様にして混合粉体を作成し、メッシュベルト上に堆積された高比重粉体層の上に厚み約７ｍｍの低比重粉体層を積層した。（積層工程）
次いで、加熱工程において、実施例１で説明した加熱発泡工程と同様に設定された加熱炉を用いて、高比重粉体層と低比重粉体層を溶融して無機系基体層と一体化された低比重発泡体層を形成し、無機系基体層の厚み約９ｍｍ、低比重発泡体層の厚み約１４ｍｍ、幅約０．４ｍ、長さ約１．２ｍの板状の実施例４の無機系発泡体を得た。
得られた無機系発泡体を縦横の長さが約１０ｃｍの大きさになるように破砕し、これを深さ約２ｍの水槽内に落下したところ、比重の大きな無機系基体層が下側になり水中を沈降し、低比重発泡体層を上向きにして無機系基体層が水槽の底部に設置された。
以上のように本実施例によれば、低比重発泡体層を上向きにして無機系基体層を湖底等に設置することができるので、表面積の大きな低比重発泡体層に水流が当たり易くなるとともに低比重発泡体層に藻が付着したり生物膜が生息し易く、低比重発泡体層で有機物の分解や水の浄化等を効率よく行うことができるため、水質改善用浄化材や漁礁等として最適な無機系発泡体が得られることが明らかになった。
【００５５】
なお、無機系粉体、貝殻粉体の含有量や粒径等を、所定の範囲内で変えて同様の評価を行ってみたが、いずれも本実施例と同様に、所定の比重に形成することができるととも水質浄化性に優れていることが確認された。
【００５６】
【発明の効果】
以上のように、本発明の無機系発泡体組成物及び無機系発泡体並びに無機系発泡体の製造方法によれば、以下のような有利な効果が得られる。
請求項１に記載の発明によれば、
（１）無機系廃材や貝殻という廃棄物を用いているので、廃棄物の再資源化を図ることができる省資源性に優れた無機系発泡体組成物を提供することができる。
（２）貝殻は硬度が低く粉砕し易いので貝殻粉体が容易に得られ、粉砕設備負荷や工数等を小さくすることができる無機系発泡体組成物を提供することができる。
（３）加熱することで、貝殻が含有する炭酸カルシウムが分解して炭酸ガスを発生し溶融した無機系粉体を発泡させて気泡を形成するとともに、貝殻が含有するフミン酸が燃焼して焼失し微細孔を形成し表面積の大きな無機系発泡体が安定して得られる無機系発泡体組成物を提供することができる。
（４）貝殻の種類によっては赤貝等のように繊維質を有し、溶融発泡して形成された気泡の周囲に位置して補強剤として機能し、気泡が破裂するのを防止する無機系発泡体組成物を提供することができる。
（５）貝殻はカルシウムイオンだけでなくマグネシウムイオンも有し、これらが、無機系粉体が溶融した溶融体の粘性を小さくして冷却時に発生する残留ひずみを少なくするので冷却時に割れ難くなり、板状等の長尺の無機系発泡体を形成し易く成形性に優れた無機系発泡体組成物を提供することができる。
（６）貝殻粉体が加熱によって分解して生成される酸化カルシウムが、水分や二酸化炭素を吸収するので吸湿性等に優れる無機系発泡体を製造することができる無機系発泡体組成物を提供することができる。
（７）酸化カルシウムが水分を吸収して生成される水酸化カルシウムが溶出し易いので、土壌改質剤として用いることができる無機系発泡体を製造することができる無機系発泡体組成物を提供することができる。
（８）加熱されて形成された無機系発泡体を水質改善用浄化材等として水中に浸漬すると、無機系発泡体の破壊面から、貝殻が含有するカルシウム、マグネシウムが水中に溶出する。これにより、水に溶解しているリン酸が、溶出したカルシウムによってリン酸カルシウム（不溶性）になり水質の改善を行うことができる。また、溶出したマグネシウムが貝類や藻類等の成育を促進することができる無機系発泡体が得られる無機系発泡体組成物を提供することができる。
【００５７】
請求項２に記載の発明によれば、請求項１の効果に加え、
（１）貝殻粉体が所定量配合されているので、加熱して無機系粉体を溶融すると最適量の炭酸ガスが発生し気泡が形成され、発泡倍率の大きな無機系発泡体が得られる無機系発泡体組成物を提供することができる。
（２）貝殻粉体の密度が小さいので容量が多く、無機系粉体に均一に混合させることができる無機系発泡体組成物を提供することができる。
【００５８】
請求項３に記載の発明によれば、請求項１又は２の効果に加え、
（１）無機系粉体の粒径が所定の範囲に調整されているので、無機系粉体の溶融温度が安定するとともに気泡の大きさも安定し、機械的強度を高めることができるとともに無機系発泡体の品質の安定性に優れた無機系発泡体組成物を提供することができる。
【００５９】
請求項４に記載の発明によれば、請求項１乃至３の内いずれか１の効果に加え、
（１）貝殻粉体の粒径が０．１〜３０００μｍなので、凝集し難く無機系粉体に点在するように分散させることができ、加熱して溶融発泡することで気泡を点在するように均一に分布させることができる無機系発泡体組成物を提供することができる。
（２）この結果、比較的径の大きな独立した気泡を形成することができ、比重が１より大きな無機系発泡体を形成することができる無機系発泡体組成物を提供することができる。
【００６０】
請求項５に記載の発明によれば、請求項１乃至３の内いずれか１の効果に加え、
（１）貝殻粉体の粒径が０．１〜１０００μｍなので、凝集し難く無機系粉体に均一に分散させることができ、加熱して溶融発泡することで気泡を均一に分布させることができる無機系発泡体組成物を提供することができる。
（２）この結果、多数の独立した気泡と、それらが多数繋がった連続気泡を形成することができ、比重が１より小さな無機系発泡体を形成することができる無機系発泡体組成物を提供することができる。
【００６１】
請求項６に記載の発明によれば、請求項１乃至３の内いずれか１の効果に加え、
（１）貝殻粉体の密度が小さく、かつ粒径が小さいので容量が多く、無機系粉体の表面に貝殻粉体をまぶした状態となり、微細な気泡を均一に分散して形成させることができる無機系発泡体組成物を提供することができる。
（２）この結果、微細な気泡が多数繋がった連続気泡を形成することができ、表面積が大きく比重が１より大きな無機系発泡体を形成することができる無機系発泡体組成物を提供することができる。
【００６２】
請求項７に記載の発明によれば、請求項１乃至６の内いずれか１の効果に加え、
（１）ガラス質廃材は、１０００℃以下の低温で軟化するものが多いので加熱炉等の設備負荷が小さく、また溶融体が粘性を有するので気泡を形成し易く比重の制御を容易に行うことができ、さらに機械的強度が高く耐久性に優れる無機系発泡体が得られる無機系発泡体組成物を提供することができる。
（２）ガラス質廃材が溶融固化した後は、カドミウム，シアン等の有害物質を溶出しないので、河川や湖等の浄化材として最適な無機系発泡体が得られる無機系発泡体組成物を提供することができる。
【００６３】
請求項８に記載の発明によれば、
（１）低比重発泡体層と一体化された無機系基体層を有しているので、機械的強度が比較的乏しい低比重発泡体層を補強することができ機械的強度を高めることができ耐久性に優れた無機系発泡体を提供することができる。
（２）無機系基体層の比重が低比重発泡体層の比重より大きいため、無機系基体層の比重を１以上に形成することにより無機系発泡体を湖，沼，海等の水中に沈めた場合には、低比重発泡体層を上向きにして無機系基体層を湖底等に設置することができる。このため、表面積の大きな低比重発泡体層に水流が当たり易くなるとともに低比重発泡体層に藻が付着したり生物膜が生息し易く、低比重発泡体層で有機物の分解や水の浄化等を効率よく行うことができる無機系発泡体を提供することができる。
【００６４】
請求項９に記載の発明によれば、
（１）混合された無機系発泡体組成物を所定の温度範囲で加熱して溶融発泡させるので、無機系粉体を十分に軟化させて貝殻粉体を完全に包み込み、貝殻粉体の分解によって発生した炭酸ガスで確実に発泡させることができ安定性に優れた無機系発泡体の製造方法を提供することができる。
（２）粒径の小さな貝殻粉体が均一に混合しているので溶融助剤として働き、全体の溶融温度を低下させる。また、貝殻粉体が無機系粉体の表面に均一に分散しているので、破壊の起点となり易い溶融斑の発生を防ぎ機械的強度を安定させる無機系発泡体の製造方法を提供することができる。
（３）加熱温度が８５０〜１１００℃好ましくは９００〜１０００℃と比較的低いので、加熱炉等の設備負荷が少なく、また省エネルギー性に優れた無機系発泡体の製造方法を提供することができる。
【００６５】
請求項１０に記載の発明によれば、
（１）積層工程において異なる組成を有する低比重粉体層と高比重粉体層を積層した後に加熱工程において溶融し一体化するので、比重が１以上の無機系基体層と比重が１未満の低比重発泡体層が一体化された無機系発泡体を容易に形成することができ生産性に優れた無機系発泡体の製造方法を提供することができる。
【図面の簡単な説明】
【図１】実施の形態１における無機系発泡体の斜視図
【図２】実施の形態２における無機系発泡体の斜視図
【図３】実施の形態２における無機系発泡体の製造装置の要部模式図
【図４】水質改善用浄化材の評価試験装置の模式図
【図５】実験開始からの経過時間とアンモニア性窒素の比濃度との関係を示す図
【図６】実験開始からの経過時間とリン酸態リンの比濃度との関係を示す図
【符号の説明】
１，１´　無機系発泡体
１ａ　基体
１ｂ　貝殻粉体
１ｃ　気泡
２　無機系基体層
３　低比重発泡体層
３ａ　境界面
４　加熱炉
５　メッシュベルト
６　第１ホッパ
６ａ　高比重粉体層
７　第２ホッパ
７ａ　低比重粉体層
１０　水質改善用浄化材の評価試験装置
１１　カラム
１２　無機系発泡体
１３　ビーカー
１４　水溶液
１５，１６　液体循環路
１７　ポンプ[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an inorganic foam composition and an inorganic foam using inorganic waste such as glassy waste, combustion ash, and brick waste, and a method for producing an inorganic foam.
[0002]
[Prior art]
Conventionally, in order to recycle glassy waste materials and coal ash, which are one type of inorganic waste materials, uniform, independent or continuous bubbles are formed in a matrix of glassy or the like using glassy waste materials or coal ash. A vitreous foam, a lightweight artificial aggregate, and the like having excellent heat insulation and sound insulation properties have been developed.
For example, Patent Literature 1 discloses “a method for producing foam glass in which a raw material obtained by mixing a limestone powder with a crushed bottle glass or the like is granulated and then heated at 810 to 960 ° C.”.
[0003]
(Patent Document 2) describes "artificial light-weight aggregates in which waste glass, a binder, and a foaming agent such as iron oxide, silicon carbide, and carbon material are mixed with coal ash, pulverized, molded, and fired. Manufacturing Method "is disclosed.
[0004]
(Patent Document 3) states that “waste glass is crushed to form a powder and granules, and at least one of a metal carbonate such as sodium carbonate, a metal carbide such as silicon carbide, and a metal nitride such as silicon nitride is added thereto. And a method for producing a glass foam to be heated. "
[0005]
Patent Document 4 discloses "a method for producing a vitreous foam in which coarsely ground glass powder and finely ground glass powder are mixed, silicon carbide is added thereto, and the mixture is heated."
[0006]
[Patent Document 1]
JP-A-58-60634
[Patent Document 2]
JP-A-11-335146
[Patent Document 3]
JP-A-11-343128
[Patent Document 4]
JP-A-11-236232
[0007]
[Problems to be solved by the invention]
However, the above-described conventional technology has the following problems.
(1) The techniques disclosed in (Patent Documents 1) and (Patent Documents 2) require a step of granulating raw materials at a stage before heat treatment, which requires granulating equipment and man-hours, and lacks productivity. Had issues.
(2) The technology disclosed in Patent Document 3 does not specify the particle size of the powdered waste glass or the foaming agent, so that even if the conditions for heating the raw materials are constant, the particle size of the waste glass or the like can be reduced. There is a problem that the melting state, the foaming state, and the like are different, and the specific gravity, the size of the bubbles, and the like are not stable, and the stability of quality is lacking.
(3) The technology disclosed in Patent Document 4 has a problem that a foam having a small specific gravity can be obtained by adjusting the particle size of glass powder, but a long foam cannot be obtained.
(4) The technologies disclosed in Patent Documents 1 to 4 use waste glass and the like as glass as a raw material, but mainly use natural resources such as limestone and chemicals such as silicon carbide as a foaming agent. Therefore, there is a problem that it promotes consumption of natural resources and the like and lacks resource saving.
[0008]
The present invention solves the above-mentioned conventional problems. In addition to the above, it is possible to recycle waste and to obtain an inorganic foam having a desired specific gravity in a stable manner. It is an object to provide an inorganic foam composition capable of forming a body.
Another object of the present invention is to provide an inorganic foam in which layers having different specific gravities are laminated and integrated.
Another object of the present invention is to provide a method for producing an inorganic foam which is excellent in energy saving and has a small equipment load such as a heating furnace, and is more reliably foamed to form air bubbles and has excellent quality stability. I do. Also, a method for producing an inorganic foam which can easily produce an inorganic foam in which an inorganic base layer having a specific gravity of 1 or more and a low specific gravity foam layer having a specific gravity of less than 1 are integrated. The purpose is to provide.
[0009]
[Means for Solving the Problems]
In order to solve the above conventional problems, an inorganic foam composition, an inorganic foam, and a method for producing an inorganic foam of the present invention have the following configurations.
[0010]
The inorganic foam composition according to claim 1 of the present invention has a configuration containing an inorganic powder obtained by pulverizing an inorganic waste material and a shell powder obtained by pulverizing a shell. are doing.
With this configuration, the following operation is obtained.
(1) Since wastes such as inorganic waste materials and shells are used, the wastes can be recycled.
(2) Since the shell has low hardness and is easily crushed, shell powder can be easily obtained, and the load on the crushing equipment and the number of steps can be reduced.
(3) By heating, the calcium carbonate contained in the shell decomposes to generate carbon dioxide gas and foam the molten inorganic powder to form bubbles, and the humic acid contained in the shell burns and burns out Thus, an inorganic foam having a large surface area and a large surface area can be stably obtained.
(4) Some types of shells have a fibrous property, such as red shellfish, and are located around the bubbles formed by melt foaming and function as a reinforcing agent to prevent the bubbles from bursting.
(5) The shell has not only calcium ions but also magnesium ions, which reduce the viscosity of the melt of the inorganic powder and reduce the residual strain generated during cooling, so that the shell is less likely to crack during cooling, It is easy to form a long inorganic foam such as a plate and has excellent moldability.
(6) Since calcium oxide generated by decomposition of shell powder by heating absorbs moisture and carbon dioxide, an inorganic foam excellent in hygroscopicity and the like can be manufactured.
(7) Since calcium hydroxide generated by absorption of water by calcium oxide is easily eluted, an inorganic foam that can be used as a soil modifier can be manufactured.
(8) When the inorganic foam formed by heating is immersed in water as a purification material for improving water quality or the like, calcium and magnesium contained in the shell elute into the water from the fracture surface of the inorganic foam. Thereby, the phosphoric acid dissolved in water becomes calcium phosphate (insoluble) by the eluted calcium, and the water quality can be improved. Further, the eluted magnesium can promote the growth of shellfish, algae and the like.
[0011]
Here, as the inorganic waste material, vitreous waste material, combustion ash, brick waste material, livestock or fish bone, and the like can be used, and one or more of these can be used in combination.
As glassy waste materials, glass bottles for chemicals, cosmetics, food seasonings, beverages, etc., plate glass, window glass, waste such as glass panels for televisions and displays, and glass products are generated. Scrap or the like is used.
As the combustion ash, coal ash or the like of a combustion device mainly using solid fuel such as coal power generation, garbage power generation, or municipal garbage incinerator is used.
As the brick waste material, red brick, refractory brick, lightweight brick, pavement brick, glaze brick, slag brick, silicate brick, cement brick, and other wastes, scrap generated from a brick product factory, and the like are used.
As the bones of livestock and fish, bones obtained when processing livestock and fish such as cows, pigs, horses, and chickens are used.
Among these inorganic waste materials, glassy waste materials are particularly preferably used. Vitreous waste materials tend to soften at a low temperature of 1000 ° C or less, so that equipment load such as a heating furnace is small. In addition, since the melt has viscosity, it is easy to form bubbles, and a long inorganic foam such as a plate is used. This is because the body is easily formed. Therefore, it can be mixed with other inorganic waste materials at a predetermined ratio to lower the melting point and increase the viscosity of the melt.
[0012]
As shells, bivalves such as oysters, scallops, red clams, clams, clams, abalones, turtles and clams, and snail shells are used.
The shell is washed with water to remove sand and the like, dried, and then crushed. When the wet pulverization is performed, the pulverization may be performed before drying.
[0013]
Grinding of inorganic waste materials and shells can be performed using a crusher such as a hammer crusher, an edge runner, a screen mill, a roller mill, an erotic fall mill, a ball mill, and a jet mill.
[0014]
The invention according to claim 2 of the present invention is the inorganic foamed composition according to claim 1, wherein the shell powder is 8 to 20 parts by weight, preferably 10 to 100 parts by weight of the inorganic powder. It has a configuration containing up to 15 parts by weight.
With this configuration, the following operation is obtained in addition to the operation obtained in the first aspect.
(1) Since a predetermined amount of shell powder is blended, when heating and melting the inorganic powder, an optimal amount of carbon dioxide gas is generated to form bubbles, and an inorganic foam having a large expansion ratio is obtained.
(2) Since the density of the shell powder is small, the shell powder has a large capacity and can be uniformly mixed with the inorganic powder.
[0015]
Here, the content of the shell powder is preferably 8 to 20 parts by weight, more preferably 10 to 15 parts by weight, based on 100 parts by weight of the inorganic powder. With respect to 100 parts by weight of the inorganic powder, as the amount of the shell powder becomes less than 10 parts by weight, the amount of carbon dioxide gas generated by decomposition of the shell powder tends to be small, and it is difficult to foam. As the amount becomes more than 15 parts by weight, A large amount of carbon dioxide gas is generated, and large cracks are generated on the surface of the inorganic foam, so that the gas escapes, the bulk is hardly increased, and the mechanical strength tends to decrease due to the cracks. In particular, if the amount is less than 10 parts by weight or more than 20 parts by weight, these tendencies are remarkable, so that it is not preferable.
[0016]
The invention according to claim 3 of the present invention is the inorganic foam composition according to claim 1 or 2, wherein the particle diameter of the inorganic powder is 0.1 to 1000 µm, preferably 0.5 to 1000 µm. 850 μm, more preferably 0.5 to 500 μm.
With this configuration, the following operation is obtained in addition to the operation obtained in the first or second aspect.
(1) Since the particle diameter of the inorganic powder is adjusted to a predetermined range, the melting temperature of the inorganic powder is stable, the size of the bubbles is stable, the mechanical strength can be increased, and the inorganic powder can be improved. Excellent foam quality stability.
[0017]
Here, the particle diameter of the inorganic powder is preferably from 0.1 to 1000 μm, preferably from 0.5 to 850 μm, more preferably from 0.5 to 500 μm. When the particle size is 0.5 to 500 μm, it is possible to obtain an inorganic foam having excellent mechanical strength and hard to be broken during cooling after heating and melting. As the particle size becomes smaller than 0.5 μm, the load and man-hours of the crushing equipment for inorganic waste materials increase, and the melting temperature tends to be difficult to control because of the tendency to be easily melted. Are not preferred because they tend to be melted and hardly bonded to each other due to a large mechanical strength, and tend to be easily broken when cooled after heating and melting. Further, this tendency becomes remarkable as the particle size becomes larger than 850 μm, and particularly, when the particle size becomes smaller than 0.1 μm or larger than 1000 μm, these tendencies become remarkable, and neither is preferable.
[0018]
Inorganic powders are collected by dry classifiers such as gravity classifiers, inertial classifiers, centrifugal classifiers, sieving machines, etc., and gravity classifiers such as Spitzkasten and spiral classifiers and centrifugal force classifiers such as hydrocyclones. Classification to a predetermined particle size is preferable because it can be surely adjusted to a predetermined range. When a wet classifier is used, drying is performed after classification, or when heating in a heating furnace, the temperature is raised after completely evaporating water or the like at around 200 ° C.
[0019]
The invention according to claim 4 of the present invention is the inorganic foam composition according to any one of claims 1 to 3, wherein the shell powder has a particle size of 0.1 to 3000 µm. It has a certain configuration.
With this configuration, the following operation is obtained in addition to the operation obtained in any one of the first to third aspects.
(1) Since the shell powder has a particle size of 0.1 to 3000 μm, it is difficult to coagulate and can be dispersed so as to be scattered in the inorganic powder. Can be evenly distributed.
(2) As a result, closed cells having a relatively large diameter can be formed, and an inorganic foam having a specific gravity larger than 1 can be formed.
[0020]
Here, the particle diameter of the shell powder refers to the major axis in the three-axis direction of the shell powder that is pulverized and formed into a thin scale-like or spherical shape.
As the particle size of the shell powder becomes smaller than 0.1 μm, the load on the crushing equipment and the number of steps increase, and the shell powder tends to agglomerate and tends to be difficult to be uniformly dispersed in the inorganic powder. The amount of gas generated when one shell powder is decomposed by heating as it rises, it is easy to form coarse bubbles, which makes it easier to crack, and the shell powder relative to the inorganic powder , The number of air bubbles decreases, and the expansion ratio of the inorganic foam tends to decrease.
The shell powder can be classified in the same manner as the inorganic powder described in claim 3. Thereby, it can be adjusted to a predetermined range without fail.
[0021]
The invention according to claim 5 of the present invention is the inorganic foam composition according to any one of claims 1 to 3, wherein the shell powder has a particle size of 0.1 to 1000 µm. It has a certain configuration.
With this configuration, the following operation is obtained in addition to the operation obtained in any one of the first to third aspects.
(1) Since the particle diameter of the shell powder is 0.1 to 1000 μm, it is difficult to aggregate and can be uniformly dispersed in the inorganic powder, and the bubbles can be uniformly distributed by heating and melting and foaming. .
(2) As a result, it is possible to form a large number of independent cells and open cells in which the cells are connected to each other, and to form an inorganic foam having a specific gravity smaller than 1.
[0022]
Here, as the particle size of the shell powder becomes smaller than 0.1 μm, the load on the crushing equipment and the number of man-hours increase, and the shell powder tends to agglomerate and tends to be difficult to be uniformly dispersed in the inorganic powder. As the size increases, the amount of gas generated when one shell powder is decomposed due to heating increases, forming coarse bubbles, and the amount of shell powder relative to the inorganic powder decreases, leading to open cells. Are not preferred, since there is a tendency that it is difficult to form them.
As the particle diameter of the shell powder, the major axis in the triaxial direction is used in the same manner as described in claim 4.
[0023]
The invention according to claim 6 of the present invention is the inorganic foamed composition according to any one of claims 1 to 3, wherein the particle diameter of the shell powder is preferably 0.01 to 50 µm. Has a configuration of 0.1 to 10 μm.
With this configuration, the following operation is obtained in addition to the operation obtained in any one of the first to third aspects.
(1) The density of shell powder is small and the particle size is small, so the capacity is large, and the surface of inorganic powder is covered with shell powder, and fine bubbles can be uniformly dispersed and formed. it can.
(2) As a result, open cells in which a number of fine cells are connected can be formed, and an inorganic foam having a large surface area and a specific gravity of more than 1 can be formed.
[0024]
Here, as the particle size of the shell powder becomes smaller than 0.1 μm, the equipment load and man-hours of the crushing equipment and the like increase, and the shell powder tends to agglomerate and is difficult to be uniformly dispersed in the inorganic powder. As the size of the shell powder becomes larger than 10 μm, the amount of shell powder relative to the inorganic powder required for forming open cells tends to be insufficient, and it tends to be difficult to form open cells. . In particular, when the particle diameter is smaller than 0.01 μm or larger than 50 μm, these tendencies are remarkable, and neither is preferable.
Further, as the shell powder, shell powder collected by a filter dust collector such as a bag filter or an air filter used when pulverizing the shell powder, an electric dust collector, or the like is preferably used. A shell filter having a particle size of 0.1 to 10 μm can be collected by a bag filter, and a shell powder having a fine particle size of about 0.01 μm can be collected by an air filter or an electrostatic precipitator. It is.
As the particle diameter of the shell powder, the major axis in the triaxial direction is used in the same manner as described in claim 4.
[0025]
The invention according to claim 7 of the present invention is the inorganic foam composition according to any one of claims 1 to 6, wherein the inorganic waste material is a vitreous waste material. ing.
With this configuration, the following operation is obtained in addition to the operation obtained in any one of the first to sixth aspects.
(1) Most of glassy waste materials soften at a low temperature of 1000 ° C. or less, so that equipment load such as a heating furnace is small, and since the melt has viscosity, bubbles are easily formed and the specific gravity can be easily controlled. And have high mechanical strength and excellent durability.
(2) After the glassy waste material is melted and solidified, harmful substances such as cadmium and cyanide are not eluted, so that an inorganic foam that is optimal as a purification material for rivers and lakes can be obtained.
[0026]
The inorganic foam according to claim 8 of the present invention is obtained by crushing an inorganic waste material, heating and melting an inorganic powder and an inorganic base layer, and crushing the inorganic waste material. A low-density foam layer in which the inorganic powder and the shell powder are heated and integrated with the inorganic base layer to form a specific gravity smaller than that of the inorganic base layer.
With this configuration, the following operation is obtained.
(1) Since it has an inorganic base layer integrated with the low specific gravity foam layer, the low specific gravity foam layer having relatively poor mechanical strength can be reinforced and the mechanical strength can be increased. Excellent durability.
(2) Since the specific gravity of the inorganic base layer is larger than the specific gravity of the low specific gravity foam layer, the inorganic foam is submerged in water such as a lake, a swamp, or the sea by forming the specific gravity of the inorganic base layer to be 1 or more. In such a case, the inorganic base layer can be placed on the bottom of a lake or the like with the low specific gravity foam layer facing upward. For this reason, the water flow easily hits the low-density foam layer having a large surface area, algae easily adhere to the low-density foam layer, and a biofilm easily inhabits, and the low-density foam layer decomposes organic substances and purifies water. Can be performed efficiently.
[0027]
Here, the inorganic base layer is formed by melting an inorganic powder obtained by pulverizing an inorganic waste material or an inorganic powder to which shell powder, calcium carbonate, dolomite, etc. are added. Things are used. Moreover, what melt | dissolved the inorganic type foamed body composition of Claim 4 can also be used. This is because the specific gravity can be 1 or more.
As the low specific gravity foam layer, one obtained by adding shell powder to an inorganic powder, heating and integrating with the inorganic base layer, and forming the specific gravity smaller than that of the inorganic base layer is used. Moreover, what melt | dissolved the inorganic type foamed body composition of Claim 5 can also be used. This is because the specific gravity can be less than 1.
[0028]
The method for producing an inorganic foam according to claim 9 of the present invention is obtained by a mixing step of mixing the inorganic foam composition according to any one of claims 1 to 7 and the mixing step. A heating and foaming step of heating the melted mixed powder to 850 to 1100 ° C., preferably 900 to 1000 ° C. to melt and foam it.
With this configuration, the following operation is obtained.
(1) Since the mixed inorganic foam composition is heated and melted and foamed in a predetermined temperature range, the inorganic powder is sufficiently softened, the shell powder is completely wrapped, and the shell powder is decomposed. Bubble can be surely foamed with the generated carbon dioxide gas and has excellent stability.
(2) Since the shell powder having a small particle size is uniformly mixed, it acts as a melting aid and lowers the entire melting temperature. In addition, since the shell powder is uniformly dispersed on the surface of the inorganic powder, the occurrence of melting spots, which are likely to be the starting points of destruction, is prevented, and the mechanical strength is stabilized.
(3) Since the heating temperature is relatively low at 850 to 1100 ° C., preferably 900 to 1000 ° C., the load on equipment such as a heating furnace is small and the energy saving is excellent.
[0029]
Here, in the heating and foaming step, the mixed powder obtained in the mixing step is filled in a mold made of stainless steel or the like, or is deposited on a mesh belt or a caterpillar made of stainless steel or the like, and the box furnace, What is heated intermittently or continuously in a heating furnace such as a shuttle kiln, a roller hearth kiln, or a tunnel type to melt the inorganic powder is used. In the heating and foaming step, bubbles are formed in the molten and softened inorganic powder by the carbon dioxide gas generated by the decomposition of the shell powder.
[0030]
As the heating temperature in the heating and foaming step, although it depends on the type of the inorganic powder, 800 to 1100C, preferably 900 to 1000C is suitably used. As the heating temperature became lower than 900 ° C., the softening of the inorganic powder was insufficient and the shell powder tended to be hardly foamed even when decomposed, and as the temperature became higher than 1000 ° C., the shell powder was decomposed and generated. Both of these are not preferred because the bubbles expand and become coarse, making it difficult to obtain fine bubbles, or the foamed material tends to re-melt into a smooth glass. In particular, when the temperature is lower than 800 ° C. or higher than 1100 ° C., these tendencies become remarkable, and neither is preferable.
In the heating foaming step, the heating is performed at a heating temperature of 800 to 1100 ° C. for 5 to 20 minutes. As the holding time is less than 5 minutes, uneven foaming tends to occur, and the size of the bubbles tends to be extremely irregular, and as the holding time exceeds 20 minutes, the bubbles tend to expand and become coarse. Absent. Further, depending on the amount of the inorganic foam composition and the thickness in the heating furnace, heat transfer unevenness is generated, and a non-uniform inorganic foam is formed.
[0031]
The molten foam obtained in the heating and foaming step is decooled in a heating furnace, or naturally cooled in air, or quenched with air or water to form a long, massive, etc. inorganic foam. Crushed or cut or split as required.
Inorganic foams can be used as materials for civil engineering, such as embankment, backfilling, backfilling, etc., as lightweight materials such as concrete and asphalt, as building materials such as heat insulating materials, soundproofing materials, etc. It can be used as a soil modifier or the like by mixing with soil. In particular, when used as a heat insulating material for underfloor, attic, walls and the like of a house, the weight of the house and the like can be reduced, and heat insulation and dehumidifying properties are imparted by a large surface area.
Further, since it contains shell powder containing calcium, magnesium, etc., and is porous and has a large surface area, it is preferable to use it as a purification material for improving water quality because it exhibits excellent water quality improvement performance. Moreover, since it is porous, algae and grasses easily prosper in the water, which is suitable as a fishing reef. In addition, it can be used as a lightweight soil material such as a roof garden or a potted plant by utilizing its water retention and light weight.
The inorganic foam can be used as a lightweight material to be buried in a reinforced concrete floor slab because it can be formed into a long inorganic foam that is hard to crack during cooling after heating and can be formed. Excellent environmental preservation and safety without problems such as material processing. Currently, lightweight materials made of Styrofoam are mainly used, so they are scattered during dismantling, polluting the surrounding environment, causing problems in waste disposal, etc., and are also a source of toxic gas in the event of a fire Because.
[0032]
The method for producing an inorganic foam according to claim 10 of the present invention comprises the steps of: a. Contains 0 to 5 parts by weight of stone powder with respect to 100 parts by weight of an inorganic powder obtained by pulverizing an inorganic waste material, or b. A laminating step of laminating a high specific gravity powder layer containing the inorganic foam composition according to claim 4 and a low specific gravity powder layer containing the inorganic foam composition according to claim 5. Heating the laminated product obtained in the laminating step to 850 to 1100 ° C., preferably 900 to 1000 ° C. to melt the high specific gravity powder layer and the low specific gravity powder layer, thereby forming the inorganic base layer and the low specific gravity foam, respectively. A heating step of forming a body layer and integrating the inorganic base layer and the low specific gravity foam layer.
With this configuration, the following operation is obtained.
(1) Since the low specific gravity powder layer and the high specific gravity powder layer having different compositions are laminated in the laminating step and then fused and integrated in the heating step, the inorganic base layer having a specific gravity of 1 or more and the specific gravity of less than 1 are used. An inorganic foam in which the low specific gravity foam layer is integrated can be easily formed, and the productivity is excellent.
[0033]
Here, as the laminating step, a. Contains 0 to 5 parts by weight of stone powder with respect to 100 parts by weight of inorganic powder obtained by pulverizing inorganic waste such as glassy waste, incinerated ash, brick waste, or b. A high specific gravity powder layer containing the inorganic foam composition according to claim 4, is laid in a stainless steel or other formwork, or deposited on a stainless steel or other mesh belt or caterpillar, and the like, The low specific gravity powder layer containing the inorganic foam composition according to claim 5 is laminated on the high specific gravity powder layer. Thereby, in the heating step, the low specific gravity foam layer is pressed and integrated with the inorganic base layer by the weight of the low specific gravity powder layer.
In addition, you may laminate | stack a high specific gravity powder layer on a low specific gravity powder layer. This is because, in the heating step, the high specific gravity powder layer is similarly pressed and integrated by its own weight.
[0034]
As the stone powder added to the inorganic powder, calcium carbonate or dolomite formed from limestone, marble, or the like is used. Also, shell powder can be used.
The stone powder is added in the range of 0 to 5 parts by weight based on 100 parts by weight of the inorganic powder in the high specific gravity powder layer. Thereby, the inorganic base layer can be slightly foamed to form air bubbles, and the surface area of the inorganic base layer can be increased.
Here, if the addition amount of the stone powder is more than 5 parts by weight, the foaming amount increases and the specific gravity tends to decrease, which is not preferable.
[0035]
In the heating step, the laminate of the high specific gravity powder layer and the low specific gravity powder layer is intermittently or continuously heated in a box furnace, a shuttle kiln, a roller hearth kiln, or a tunnel furnace. The specific gravity powder layer and the high specific gravity powder layer are melted to form an inorganic base layer and a low specific gravity foam layer, and are integrated at the boundary surface.
Since the heating temperature in the heating step is the same as that described in the heating and foaming step of claim 7, the description is omitted.
As the inorganic waste material, the one described in claim 1 is used, and the particle diameter of the inorganic powder obtained by pulverizing the inorganic waste material can be the same as that described in claim 3, so that the description is omitted. I do.
[0036]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
(Embodiment 1)
FIG. 1 is a perspective view of an inorganic foam according to Embodiment 1 of the present invention.
In FIG. 1, reference numeral 1 denotes an inorganic foam according to the first embodiment, 1a denotes a substrate of an inorganic foam 1 formed by melting an inorganic powder obtained by pulverizing an inorganic waste such as a glass waste, and 1b. Is a shell powder formed by crushing a shell such as an oyster shell and added to the inorganic powder; 1c is a mixture of open cells and closed cells formed in the base 1a by foaming of calcium carbonate in the shell powder 1b. Become bubbles. Although the main component of the shell powder 1b is calcium carbonate, it also contains other components and does not all thermally decompose, so that the shell powder 1b remains in the substrate 1a particularly when the particle size is large.
Here, in the present embodiment, the particle diameter of the inorganic powder is formed to be 0.1 to 1000 μm, preferably 0.5 to 850 μm, more preferably 0.5 to 500 μm. Further, the particle diameter of the shell powder is formed to be 0.1 to 3000 μm.
[0037]
Since the inorganic foam according to Embodiment 1 is configured as described above, the following effects can be obtained.
(1) Since wastes such as inorganic waste materials and shells are used, the wastes can be recycled.
(2) Since the shell has low hardness and is easily crushed, shell powder can be easily obtained, and the load on the crushing equipment and the number of steps can be reduced.
(3) By heating, the calcium carbonate contained in the shell decomposes to generate carbon dioxide gas and foam the molten inorganic powder to form bubbles, and the humic acid contained in the shell burns and burns out Thus, an inorganic foam having a large surface area and a large surface area can be stably obtained.
(4) The shell has not only calcium ions but also magnesium ions, which reduce the viscosity of the melt of the inorganic powder and reduce the residual strain generated during cooling, so that the shell is less likely to crack during cooling, It is easy to form a long inorganic foam such as a plate and has excellent moldability.
(5) Since calcium oxide generated by decomposition of shell powder by heating absorbs water and carbon dioxide, an inorganic foam excellent in hygroscopicity and the like can be manufactured.
(6) Since calcium hydroxide generated by absorption of water by calcium oxide is easily eluted, an inorganic foam that can be used as a soil modifier can be manufactured.
(7) When the inorganic foam formed by heating is immersed in water, calcium and magnesium contained in the shell powder remaining on the substrate elute from the fracture surface of the inorganic foam into the water. Thereby, the phosphoric acid dissolved in water becomes calcium phosphate (insoluble) by the eluted calcium, and the water quality can be improved. In addition to the large surface area, the eluted magnesium can promote the growth of shellfish, algae, etc., and is optimal as a fishing reef.
(8) Since the particle diameter of the inorganic powder is adjusted to a predetermined range, the melting temperature of the inorganic powder is stabilized, the size of the bubbles is also stabilized, the mechanical strength can be increased, and the inorganic powder can be improved. Excellent foam quality stability.
(9) Since the particle diameter of the shell powder is 0.1 to 3000 μm, it is hard to aggregate and can be dispersed so as to be scattered in the inorganic powder, and the air bubbles are uniformly distributed so as to be scattered in the substrate. be able to. As a result, independent cells having a relatively large diameter can be formed, and an inorganic foam having a specific gravity of more than 1 can be obtained.
[0038]
Here, in the present embodiment, the case where the particle size of the shell powder is formed in the range of 0.1 to 3000 μm is described, but the shell powder may be formed in the range of 0.1 to 1000 μm. Thereby, the following operation is obtained.
(1) Shell powder is hardly agglomerated and can be uniformly dispersed in inorganic powder. By heating and melt-foaming, bubbles can be uniformly distributed in the substrate.
(2) As a result, it is possible to form a large number of independent cells and open cells in which the cells are connected to each other, and to form an inorganic foam having a specific gravity smaller than 1.
[0039]
Further, the particle size of the shell powder can be formed to 0.01 to 50 μm, preferably 0.1 to 10 μm. Thereby, the following operation is obtained.
(1) The shell powder has a low density and a small particle size, so it has a large capacity. The surface of the inorganic powder is covered with the shell powder, and fine bubbles are uniformly dispersed and formed in the substrate. Can be done.
(2) As a result, open cells in which a number of fine cells are connected can be formed, and an inorganic foam having a large surface area and a specific gravity of more than 1 can be formed.
[0040]
(Embodiment 2)
FIG. 2 is a perspective view of the inorganic foam according to the second embodiment, and FIG. 3 is a schematic diagram of a main part of an inorganic foam manufacturing apparatus according to the second embodiment.
In FIG. 2, reference numeral 1 'denotes an inorganic foam according to the second embodiment, and reference numeral 2 denotes an inorganic powder having a particle diameter of 0.1 to 1000 [mu] m obtained by pulverizing an inorganic waste such as a vitreous waste. The inorganic base layer 3 obtained is obtained by crushing inorganic waste materials such as glassy waste materials. The inorganic powder having a particle size of 0.1 to 1000 μm and the particle size obtained by crushing shells such as oyster shells. A shell powder of 0.1 to 1000 μm is mixed, heated and melted to form a low specific gravity foam layer integrated with the inorganic base layer 2, and 3 a denotes a boundary between the inorganic base layer 2 and the low specific gravity foam layer 3 Plane.
3, reference numeral 4 denotes a heating furnace such as a roller hearth kiln, 5 denotes a mesh belt made of stainless steel or the like which moves in the heating furnace 4, 6 denotes a first hopper disposed on the mesh belt 5, and 6a denotes a first hopper. 6 is a high-specific-gravity powder layer supplied and deposited at a predetermined thickness on the mesh belt 5. The high specific gravity powder layer 6a contains 0 to 5 parts by weight of stone powder such as calcium carbonate for 100 parts by weight of inorganic powder obtained by pulverizing inorganic waste such as glassy waste. Reference numeral 7 denotes a second hopper disposed on the mesh belt 5 between the first hopper 6 and the heating furnace 4, and reference numeral 7a denotes a second hopper 7 which is deposited on the high specific gravity powder layer 6a with a predetermined thickness and laminated. It is a low specific gravity powder layer formed. The low specific gravity powder layer 7a contains an inorganic foam composition obtained by adding a shell powder having a particle size of 0.1 to 1000 μm to an inorganic powder having a particle size of 0.1 to 1000 μm. Things.
[0041]
A method for producing the inorganic foam according to Embodiment 2 configured as described above will be described below.
First, an inorganic waste material such as a vitreous waste material is pulverized to form an inorganic powder having a particle size of 0.1 to 1000 μm. A mixture obtained by adding 0 to 5 parts by weight of a stone powder such as calcium carbonate to 100 parts by weight of the inorganic powder is stored in the first hopper 6. In addition, inorganic waste such as glassy waste is pulverized to form inorganic powder having a particle size of 0.1 to 1000 μm. Further, shells such as oyster shells are crushed to form shell powder having a particle size of 0.1 to 1000 μm. A mixture obtained by adding and mixing 8 to 20 parts by weight of shell powder with respect to 100 parts by weight of the inorganic powder is stored in the second hopper 7. In the laminating step, an inorganic powder or the like is deposited on the mesh belt 5 from the first hopper 6 to form a high specific gravity powder layer 6a. Next, an inorganic powder or the like is deposited from the second hopper 7 on the high specific gravity powder layer 6a, and the low specific gravity powder layer 7a is laminated.
Next, in the heating step, the laminate in which the high specific gravity powder layer 6a and the low specific gravity powder layer 7a are laminated is heated in the heating furnace 4 to 850 to 1100 ° C, preferably 900 to 1000 ° C. As a result, the high specific gravity powder layer 6a melts to form the inorganic base layer 2, the low specific gravity powder layer 7a melts to form the low specific gravity foam layer 3, and the low specific gravity foam layer 3 Is pressed to the inorganic base layer 2 so that the low specific gravity foam layer 3 and the inorganic base layer 2 are integrated.
[0042]
As described above, since the inorganic foam according to Embodiment 2 is configured, the following effects can be obtained.
(1) Since it has an inorganic base layer integrated with the low specific gravity foam layer, the low specific gravity foam layer having relatively poor mechanical strength can be reinforced and the mechanical strength can be increased. Excellent durability.
(2) Since the specific gravity of the inorganic base layer is larger than the specific gravity of the low specific gravity foam layer, the inorganic foam is submerged in water such as a lake, a swamp, or the sea by forming the specific gravity of the inorganic base layer to be 1 or more. In such a case, the inorganic base layer can be placed on the bottom of a lake or the like with the low specific gravity foam layer facing upward. For this reason, the water flow easily hits the low-density foam layer having a large surface area, algae easily adhere to the low-density foam layer, and a biofilm easily inhabits, and the low-density foam layer decomposes organic substances and purifies water. Can be performed efficiently.
[0043]
Further, according to the method for producing an inorganic foam in the second embodiment, the following effects can be obtained.
(1) Since the low specific gravity powder layer and the high specific gravity powder layer having different compositions are laminated in the laminating step and then fused and integrated in the heating step, the inorganic base layer having a specific gravity of 1 or more and the specific gravity of less than 1 are used. An inorganic foam in which the low specific gravity foam layer is integrated can be easily formed, and the productivity is excellent.
[0044]
In the present embodiment, the case where the high specific gravity powder layer in which the inorganic powder and the stone powder are mixed is used has been described, but the inorganic powder formed to have a particle size of 0.1 to 1000 μm has a particle size of 0.1 to 1000 μm. A high specific gravity powder layer containing an inorganic foam composition to which a shell powder formed to have a thickness of 0.1 to 3000 μm is added can also be used. Thus, an inorganic base layer having a specific gravity of more than 1 and containing shell powder can be obtained. This inorganic base layer elutes calcium and magnesium when immersed in water, and thus is optimal as a purifying material or a fishing reef.
[0045]
【Example】
Hereinafter, the present invention will be described specifically with reference to examples. Note that the present invention is not limited to these examples.
(Example 1)
Vitreous waste materials such as glass bottles and window glass as inorganic waste materials were roughly pulverized to a mean particle size of 2 to 3 mm using a pulverizer such as an edge runner. Next, it was finely pulverized using a pulverizer such as an erotic fall mill. Next, the particles were classified using a classifier such as a vibrating sieve to obtain an inorganic powder having a particle size of 0.1 to 1000 μm.
Next, shells such as oysters, scallops, and red shells were washed with water and dried, and then coarsely pulverized to a mean particle size of 2 to 3 mm using a pulverizer such as an edge runner. Next, it was finely pulverized using a pulverizer such as an erotic fall mill. Next, the particles were classified using a classifier such as a vibrating sieve to obtain shell powder having a particle size of 0.1 to 1000 μm.
In the mixing step, the pulverized and classified inorganic foam composition is thoroughly mixed with 100 parts by weight of the inorganic powder and 12 parts by weight of the shell powder in a mixer such as a stirring mold to obtain a mixed powder. Got.
In the heating and foaming step, a roller hearth kiln in which a 1.5 m-wide mesh belt made of stainless steel or the like was stretched over a length of 25 m was used as a heating furnace. The obtained mixed powder was deposited on the mesh belt to a thickness of about 7 mm, a width of about 0.4 m, and a length of 1.2 m along the longitudinal direction of the mesh belt. The mesh belt is configured such that the first zone 600 to 750 ° C., the second zone 850 ° C., the third zone 940 ° C., the fourth zone 960 ° C., and the heating furnace maintained at the 5.6 zone 940 ° C. The mixture is set to pass for a passage time of 10 minutes, and the mixed powder entering the heating furnace is melted and foamed for 30 to 60 minutes, and has a thickness of about 15 mm, a width of about 0.4 m, and a length of about 1. A 2 m plate-shaped inorganic foam of Example 1 was obtained.
When the specific gravity of the inorganic foam of Example 1 was measured, it was 0.6 g / cm. ³ Met. When the fracture surface was observed, it was confirmed that bubbles having an inner diameter of 0.3 to 2 mm were uniformly distributed.
[0046]
(Example 2)
In order to produce the inorganic foam of Example 1, shells such as oysters, scallops, and red shells were finely pulverized using a pulverizer such as an erotic fall mill. The inorganic foam of Example 2 was manufactured using shell powder having a particle size of 0.1 to 10 μm collected by a dust device or the like. An inorganic foam of Example 2 was obtained in the same manner as in Example 1 except that 11 parts by weight of shell powder having a particle size of 0.1 to 10 μm was added and mixed with 100 parts by weight of the inorganic powder. .
When the specific gravity of the inorganic foam of Example 2 was measured, it was 1.1 g / cm. ³ Met. It was confirmed that when this was immersed in water, it sank. When the fracture surface was observed, it was confirmed that bubbles having an inner diameter of 0.2 to 1 mm were uniformly distributed.
[0047]
(Comparative Example 1)
The inorganic foam of Comparative Example 1 was prepared in the same manner as in Example 1 except that 4 parts by weight of silicon carbide (average particle size: 3.9 μm, product name: C-4000F) was added to and mixed with 100 parts by weight of the inorganic powder. Got a body.
When the specific gravity of the inorganic foam of Comparative Example 1 was measured, it was 0.4 g / cm. ³ Met.
[0048]
(Dissolution test)
The results of evaluating the amount of harmful substances eluted when the inorganic foams of Examples 1 and 2 were immersed in water are shown in Table 1.
[Table 1]

In the measurement methods shown in (Table 1), those indicated as "JK0102" are an abbreviation for "JIS K0102", and those indicated as "S49 notification" are described in "Notification of the Environment Agency in 1974". What is displayed as "S46 Announcement" is an abbreviation of "Notification of Environment Agency in 1971".
As a result, it was clarified that no harmful substance was eluted according to the inorganic foam of this example.
[0049]
(Evaluation as a purification carrier for water quality improvement)
The inorganic foams of Examples 1 and 2 and Comparative Example 1 were evaluated as purification materials for improving water quality.
FIG. 4 is a schematic diagram of a water quality improvement purifying material evaluation test apparatus.
In FIG. 4, reference numeral 10 denotes an apparatus for evaluating and testing a purification material for improving water quality, 11 denotes a column having a capacity of 100 ml, and 12 denotes examples 1 and 2, which are cut or crushed into a substantially cubic shape having a side of about 1 cm and filled in the column 11. Inorganic foam as a sample, etc., 13 is a beaker having a capacity of about 1 liter, 14 contains 0.4 mg / L of ammonia nitrogen and 0.2 mg / L of phosphoric acid phosphorus and is injected into the beaker 13. About 1 liter of the aqueous solution, 15 is a liquid circulation path connected to the downstream side of the column 11 and the beaker 13 and supplies the aqueous solution 14 having passed through the column 11 to the beaker 13, and 16 is connected to the beaker 13 and the upstream side of the column 11. A liquid circulation path for supplying the aqueous solution 14 in the beaker 13 to the column 11, and a pump 17 such as a roller tube pump disposed in the liquid circulation path 16 and circulating the aqueous solution 14. .
In this evaluation test, the water purification performance of the inorganic foam 12 having substantially the same volume and packed in the column 11 having a capacity of 100 ml was evaluated. The inorganic foam 12 was cut or crushed into a substantially cubic shape having a side of about 1 cm, and then naturally dried in a room at room temperature for 10 days, and packed in the column 11. The filling amount was 25.5 g for the inorganic foam of Example 1, 50.2 g for the inorganic foam of Example 2, and 20.1 g for the inorganic foam of Comparative Example 1. The pump 17 was adjusted so that the flow rate of the aqueous solution 14 passing through the column 11 was 200 ml / h. The reason why ammonia nitrogen was set to 0.4 mg / L and phosphoric acid phosphorus was set to 0.2 mg / L was that a river with a considerably large pollution load was assumed.
[0050]
After starting the experiment by driving the pump 17 using the evaluation test apparatus 10 configured as described above, the aqueous solution 14 after 0, 1, 3, 5, 12, 24, and 48 hours was collected from the beaker 13. The aqueous solution was measured for ammonia nitrogen and phosphoric acid phosphorus.
The results are shown in FIGS.
FIG. 5 is a diagram showing the relationship between the elapsed time from the start of the experiment and the specific concentration of ammoniacal nitrogen, and FIG. 6 is a diagram showing the relationship between the elapsed time from the start of the experiment and the specific concentration of phosphoric acid phosphorus. . Here, the specific concentration indicates the ratio of the concentration of ammonia nitrogen or the like at each elapsed time when the concentration of ammonia nitrogen or the like before the start of the experiment (elapsed time 0) is set to 1.
[0051]
As shown in FIG. 5, in the inorganic foams of Examples 1 and 2 using shell powder, the specific concentration of ammonia nitrogen was reduced to 0.2 or less in about 48 hours from the start of the test. I was able to. From this fact, with respect to ammonia nitrogen, the inorganic foams of Examples 1 and 2 using shell powder have almost the same water quality improving effect as the inorganic foam of Comparative Example 1 using silicon carbide. It became clear to show.
[0052]
Next, as shown in FIG. 6, the specific concentration of phosphoric acid phosphorus could be reduced to 0.4 or less in 48 hours from the start of the experiment using the inorganic foam of Example 1. On the other hand, in the case of the inorganic foam of Comparative Example 1, the specific concentration was about 0.7 48 hours after the start of the experiment.
This suggests that the calcium and magnesium contained in the shell elute from the fractured surface of the inorganic foam into the water, and the phosphoric acid phosphorus becomes calcium phosphate (insoluble), thus improving the water quality. are doing. The ability of the inorganic foam of Example 1 to remove phosphoric acid phosphorus is higher than that of the inorganic foam of Example 2 because the particle size of the shell powder used in the inorganic foam of Example 1 is higher. It is presumed that the amount of shell powder remaining in the substrate after foaming is large because it is as large as 0.1 to 1000 μm.
As described above, according to the present example, it is possible to obtain an inorganic foam that is excellent in removing ammoniacal nitrogen and phosphoric acid phosphorus and is optimal as a water quality improving purification material in which no harmful substances are eluted. It was revealed.
[0053]
(Example 3)
A mixed powder obtained by adding and mixing 11 parts by weight of a shell powder having a particle size of 0.1 to 3000 μm with 100 parts by weight of an inorganic powder having a particle size of 0.1 to 1000 μm formed in the same manner as in Example 1. The body was made and deposited on a mesh belt to a thickness of about 7 mm.
Next, the mixture was heated and melted and foamed in a heating furnace set in the same manner as in Example 1 to obtain an inorganic foam of Example 3.
When the specific gravity of the inorganic foam of Example 3 was measured, it was 1.1 g / cm. ³ Met. It was confirmed that when this was immersed in water, it sank. When the fracture surface was observed, it was confirmed that bubbles having an inner diameter of 0.2 to 3 mm were distributed.
[0054]
(Example 4)
Stone powder such as calcium carbonate formed from marble or the like having a particle size of 0.1 to 20 μm is added to 100 parts by weight of an inorganic powder having a particle size of 0.1 to 1000 μm formed in the same manner as in Example 1. A mixture of 4 parts by weight was prepared and deposited on a mesh belt to form a high specific gravity powder layer having a thickness of about 7 mm.
Next, a mixed powder was prepared in the same manner as in Example 1, and a low specific gravity powder layer having a thickness of about 7 mm was laminated on the high specific gravity powder layer deposited on the mesh belt. (Lamination process)
Next, in the heating step, the high specific gravity powder layer and the low specific gravity powder layer are melted and integrated with the inorganic base layer using a heating furnace set in the same manner as the heating and foaming step described in Example 1. The low specific gravity foam layer was formed, and the inorganic base layer had a thickness of about 9 mm, the low specific gravity foam layer had a thickness of about 14 mm, a width of about 0.4 m, and a length of about 1.2 m. A foam was obtained.
When the obtained inorganic foam was crushed so that the length and width became about 10 cm in size and dropped into a water tank having a depth of about 2 m, the inorganic base layer having a large specific gravity was placed below. The inorganic base layer was placed on the bottom of the water tank with the low specific gravity foam layer facing upward.
As described above, according to the present embodiment, the inorganic substrate layer can be installed on the bottom of a lake or the like with the low specific gravity foam layer facing upward, so that the water flow can easily hit the low specific gravity foam layer having a large surface area. Algae easily adheres to the low-density foam layer, and biofilms can easily inhabit it.The low-density foam layer can efficiently decompose organic substances and purify water. It became clear that an optimal inorganic foam was obtained.
[0055]
The same evaluation was performed by changing the content and particle size of the inorganic powder and shell powder within a predetermined range. It was confirmed that it was possible to excel in water purification.
[0056]
【The invention's effect】
As described above, according to the inorganic foam composition, the inorganic foam, and the method for producing an inorganic foam of the present invention, the following advantageous effects can be obtained.
According to the first aspect of the present invention,
(1) Since inorganic waste materials and shells are used, it is possible to provide an inorganic foam composition which is excellent in resource saving and can recycle waste.
(2) The shell has low hardness and is easily crushed, so that shell powder can be easily obtained, and an inorganic foam composition that can reduce the load on the crushing equipment and the number of steps can be provided.
(3) By heating, the calcium carbonate contained in the shell decomposes to generate carbon dioxide gas and foam the molten inorganic powder to form bubbles, and the humic acid contained in the shell burns and burns out The present invention can provide an inorganic foam composition in which fine pores are formed and an inorganic foam having a large surface area can be stably obtained.
(4) Some types of shells have a fibrous property, such as red shellfish, and are located around the bubbles formed by melting and foaming, function as a reinforcing agent, and prevent inorganic bubbles from bursting. A body composition can be provided.
(5) The shell has not only calcium ions but also magnesium ions, which reduce the viscosity of the melt of the inorganic powder and reduce the residual strain generated during cooling, so that the shell is less likely to crack during cooling, It is possible to provide an inorganic foam composition which is easy to form a long inorganic foam such as a plate and has excellent moldability.
(6) Provided is an inorganic foam composition capable of producing an inorganic foam having excellent hygroscopicity, because calcium oxide generated by decomposition of shell powder by heating absorbs moisture and carbon dioxide. can do.
(7) An inorganic foam composition capable of producing an inorganic foam that can be used as a soil modifier because calcium hydroxide generated by absorption of water by calcium oxide is easily eluted. can do.
(8) When the inorganic foam formed by heating is immersed in water as a purification material for improving water quality or the like, calcium and magnesium contained in the shell elute into the water from the fracture surface of the inorganic foam. Thereby, the phosphoric acid dissolved in water becomes calcium phosphate (insoluble) by the eluted calcium, and the water quality can be improved. Further, it is possible to provide an inorganic foam composition from which an eluted magnesium can provide an inorganic foam capable of promoting the growth of shellfish, algae, and the like.
[0057]
According to the invention described in claim 2, in addition to the effect of claim 1,
(1) Since a predetermined amount of shell powder is blended, when heating and melting the inorganic powder, an optimum amount of carbon dioxide gas is generated to form bubbles, and an inorganic foam having a large expansion ratio is obtained. A system-based foam composition can be provided.
(2) Since the density of the shell powder is small, the capacity is large, and an inorganic foam composition that can be uniformly mixed with the inorganic powder can be provided.
[0058]
According to the invention described in claim 3, in addition to the effect of claim 1 or 2,
(1) Since the particle diameter of the inorganic powder is adjusted to a predetermined range, the melting temperature of the inorganic powder is stable, the size of the bubbles is stable, the mechanical strength can be increased, and the inorganic powder can be improved. An inorganic foam composition excellent in stability of foam quality can be provided.
[0059]
According to the invention described in claim 4, in addition to the effect of any one of claims 1 to 3,
(1) Since the shell powder has a particle size of 0.1 to 3000 μm, it is difficult to coagulate and can be dispersed so as to be scattered in the inorganic powder. It is possible to provide an inorganic foam composition that can be uniformly distributed in the composition.
(2) As a result, it is possible to provide an inorganic foam composition capable of forming closed cells having a relatively large diameter and forming an inorganic foam having a specific gravity larger than 1.
[0060]
According to the invention described in claim 5, in addition to the effect of any one of claims 1 to 3,
(1) Since the particle diameter of the shell powder is 0.1 to 1000 μm, it is difficult to aggregate and can be uniformly dispersed in the inorganic powder, and the bubbles can be uniformly distributed by heating and melting and foaming. An inorganic foam composition can be provided.
(2) As a result, it is possible to provide an inorganic foam composition capable of forming a large number of independent cells and continuous cells in which the cells are connected to each other, and capable of forming an inorganic foam having a specific gravity smaller than 1. can do.
[0061]
According to the invention described in claim 6, in addition to the effect of any one of claims 1 to 3,
(1) The density of shell powder is small and the particle size is small, so the capacity is large, and the surface of inorganic powder is covered with shell powder, and fine bubbles can be uniformly dispersed and formed. It is possible to provide a possible inorganic foam composition.
(2) As a result, it is possible to provide an inorganic foam composition that can form open cells in which a number of fine bubbles are connected, and that can form an inorganic foam having a large surface area and a specific gravity greater than 1. Can be.
[0062]
According to the invention described in claim 7, in addition to the effect of any one of claims 1 to 6,
(1) Most of glassy waste materials soften at a low temperature of 1000 ° C. or less, so that equipment load such as a heating furnace is small, and since the melt has viscosity, bubbles are easily formed and the specific gravity can be easily controlled. In addition, it is possible to provide an inorganic foam composition from which an inorganic foam having high mechanical strength and excellent durability can be obtained.
(2) After the glassy waste material is melted and solidified, it does not elute harmful substances such as cadmium and cyanide, and thus provides an inorganic foam composition that can obtain an inorganic foam suitable as a purification material for rivers and lakes. can do.
[0063]
According to the invention described in claim 8,
(1) Since it has an inorganic base layer integrated with the low specific gravity foam layer, the low specific gravity foam layer having relatively poor mechanical strength can be reinforced and the mechanical strength can be increased. An inorganic foam having excellent durability can be provided.
(2) Since the specific gravity of the inorganic base layer is larger than the specific gravity of the low specific gravity foam layer, the inorganic foam is submerged in water such as a lake, a swamp, or the sea by forming the specific gravity of the inorganic base layer to be 1 or more. In such a case, the inorganic base layer can be placed on the bottom of a lake or the like with the low specific gravity foam layer facing upward. For this reason, the water flow easily hits the low-density foam layer having a large surface area, algae easily adhere to the low-density foam layer, and a biofilm easily inhabits. Can be provided efficiently.
[0064]
According to the ninth aspect of the present invention,
(1) Since the mixed inorganic foam composition is heated and melted and foamed in a predetermined temperature range, the inorganic powder is sufficiently softened, the shell powder is completely wrapped, and the shell powder is decomposed. It is possible to provide a method for producing an inorganic foam which can be reliably foamed with the generated carbon dioxide gas and has excellent stability.
(2) Since the shell powder having a small particle size is uniformly mixed, it acts as a melting aid and lowers the entire melting temperature. Further, since the shell powder is uniformly dispersed on the surface of the inorganic powder, it is possible to provide a method for producing an inorganic foam which stabilizes mechanical strength by preventing the occurrence of melting spots which are likely to be a starting point of destruction. it can.
(3) Since the heating temperature is relatively low at 850 to 1100 ° C., preferably 900 to 1000 ° C., it is possible to provide a method for producing an inorganic foam having a small equipment load such as a heating furnace and excellent energy saving. .
[0065]
According to the tenth aspect,
(1) Since the low specific gravity powder layer and the high specific gravity powder layer having different compositions are laminated in the laminating step and then fused and integrated in the heating step, the inorganic base layer having a specific gravity of 1 or more and the specific gravity of less than 1 are used. An inorganic foam having a low specific gravity foam layer integrated therewith can be easily formed, and a method for producing an inorganic foam excellent in productivity can be provided.
[Brief description of the drawings]
FIG. 1 is a perspective view of an inorganic foam according to a first embodiment.
FIG. 2 is a perspective view of an inorganic foam according to a second embodiment.
FIG. 3 is a schematic diagram of a main part of an apparatus for manufacturing an inorganic foam according to a second embodiment.
FIG. 4 is a schematic view of an apparatus for evaluating and testing a purification material for improving water quality.
FIG. 5 is a diagram showing the relationship between the elapsed time from the start of the experiment and the specific concentration of ammoniacal nitrogen.
FIG. 6 is a diagram showing the relationship between the elapsed time from the start of the experiment and the specific concentration of phosphoric acid phosphorus.
[Explanation of symbols]
1,1 'inorganic foam
1a Substrate
1b Shell powder
1c bubbles
2 Inorganic base layer
3 Low specific gravity foam layer
3a Boundary surface
4 heating furnace
5 mesh belt
6 First hopper
6a High specific gravity powder layer
7 Second hopper
7a Low specific gravity powder layer
10 Apparatus for evaluating and testing water purifying materials
11 columns
12 Inorganic foam
13 Beaker
14 aqueous solution
15, 16 liquid circulation path
17 Pump

Claims (10)

An inorganic foam composition comprising: an inorganic powder obtained by crushing an inorganic waste material; and a shell powder obtained by crushing a shell. The inorganic foam composition according to claim 1, wherein the shell powder is contained in an amount of 8 to 20 parts by weight, preferably 10 to 15 parts by weight, based on 100 parts by weight of the inorganic powder. The inorganic foam composition according to claim 1, wherein the particle diameter of the inorganic powder is 0.1 to 1000 μm, preferably 0.5 to 850 μm, more preferably 0.5 to 500 μm. object. The inorganic foam composition according to any one of claims 1 to 3, wherein the shell powder has a particle size of 0.1 to 3000 µm. The inorganic foam composition according to any one of claims 1 to 3, wherein the shell powder has a particle size of 0.1 to 1000 µm. The inorganic foam composition according to any one of claims 1 to 3, wherein the shell powder has a particle size of 0.01 to 50 µm, preferably 0.1 to 10 µm. The inorganic waste foam composition according to any one of claims 1 to 6, wherein the inorganic waste material is a vitreous waste material. An inorganic base layer obtained by heating and melting an inorganic powder obtained by pulverizing an inorganic waste material; and an inorganic base and shell powder obtained by heating an inorganic powder and a shell powder obtained by pulverizing an inorganic waste material. A low-density foam layer integrated with the layer and having a specific gravity smaller than that of the inorganic base layer. A mixing step of mixing the inorganic foam composition according to any one of claims 1 to 7, and heating the mixed powder obtained in the mixing step to 850 to 1100 ° C, preferably 900 to 1000 ° C. And a heating and foaming step of melt-foaming the foam. a. Contains 0 to 5 parts by weight of stone powder with respect to 100 parts by weight of an inorganic powder obtained by pulverizing an inorganic waste material, or b. A laminating step of laminating a high specific gravity powder layer containing the inorganic foam composition according to claim 4 and a low specific gravity powder layer containing the inorganic foam composition according to claim 5; ,
The laminate obtained in the laminating step is heated to 850 to 1100 ° C., preferably 900 to 1000 ° C. to melt the high specific gravity powder layer and the low specific gravity powder layer, thereby respectively forming an inorganic base layer and a low specific gravity foam. A heating step of forming a layer and integrating the inorganic base layer and the low specific gravity foam layer,
A method for producing an inorganic foam, comprising:

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