JP4009084B2

JP4009084B2 - Sodium nitrate explosive

Info

Publication number: JP4009084B2
Application number: JP2001327753A
Authority: JP
Inventors: 京一渡辺; 武小林; 敏洋沖津
Original assignee: 日本工機株式会社
Priority date: 2001-10-25
Filing date: 2001-10-25
Publication date: 2007-11-14
Anticipated expiration: 2021-10-25
Also published as: JP2003137684A

Description

【０００１】
【発明の属する技術分野】
本発明は、建設業、砕石、採鉱等の発破作業に使用される産業用爆薬の硝安油剤爆薬に関する。
【０００２】
【従来の技術】
硝安油剤爆薬は、一般にポーラスプリル硝酸アンモニウム(以下ポーラスプリル硝安という)９４重量％、軽油６重量％からなり、安全性が高く、安価であり、また流動性が良い粒状爆薬であることから効率的な装填作業ができるなど多くの利点があるため、他の産業爆薬に比べて大量に消費されている。
硝安油剤爆薬の消費コストを低減させる方法としては、硝安油剤爆薬の価格を下げることが当然考えられるが、もうひとつの方法として、硝安油剤爆薬の嵩比重を低下させても威力がほぼ同等ならば、装薬孔（ボアホール）に装填した場合、装薬孔単位容積当たりの硝安油剤爆薬の使用重量を減らすことによって、発破作業における爆薬コストの低減が可能となる。
【０００３】
そこで従来、硝安粒子そのものの密度を低下させたポーラスプリル硝安、例えば、ポーラス度を向上させたり、或いは粒子内に気泡剤を含有させ密度低下を図ることにより、得られる硝安油剤爆薬の嵩比重の低下を図ってきた。
なお、ボアホール単位容積当たりの硝安油剤爆薬の使用重量が減少すれば、破砕効果の低下が懸念されるが、ポーラス度を向上させ比表面積を大きくして粒子の密度を低下させたポーラスプリル硝安の使用により硝安油剤爆薬の反応性が向上するため、硝安油剤爆薬の使用量を若干減らしても発破作業現場における破砕効果にはほとんど影響がないことがわかった。
【０００４】
ポーラスプリル硝安は、粒子内部に連続した多数の空隙を持つ多孔性の球体であり、燃料油と混合した場合、燃料油はこの空隙に浸透、吸着する。
上述の様に粒子密度を低下させたポーラスプリル硝安（嵩比重が０．７５程度以下のもの）は、通常密度（嵩比重が０．８０程度以上のもの）のポーラスプリル硝安と比べ、粒子内に空隙が多く比表面積が大きいため、粒子が低密度化されるとともに必然的に燃料油の吸収性が向上する。
このように燃料油の吸収性が向上するため、酸化剤成分であるポーラスプリル硝安と燃料油との接触面積が増える。
硝安油剤爆薬の爆発反応は、燃料油とポーラスプリル硝安との接触面における表面での酸化還元反応である。
したがって、当然、ポーラスプリル硝安と燃料油との接触面積が大きいほど反応性は良くなる。
つまり、上述の様にしてポーラスプリル硝安の粒子密度を下げること（比表面積の増大）により、このポーラスプリル硝安を使用した硝安油剤爆薬の反応性は向上する。
【０００５】
実験によると、このようにして得られた比表面積の大きなポーラスプリル硝安は、大凡、嵩比重が０．７付近を下回ると６号雷管起爆性を有する可能性が極めて強くなる。
【０００６】
比表面積の大きな低比重ポーラスプリル硝安は、前述したように反応性が向上し、そのため爆速が速くなり、威力を向上させるという良い効果をもたらす反面、同時に感度が鋭敏になる。
【０００７】
そこで、これを鈍感にするため硝安油剤爆薬に不活性な物質を混合する方法がある。
不活性な物質を混合することにより、硝安油剤爆薬の反応性は低下し、鈍感化される。また、この不活性な物質を用いる場合、硝安油剤爆薬より嵩比重の低いものを用いれば、硝安油剤爆薬の嵩比重をさらに低下することもできる。
使用される不活性な物質としては、例えば、ガラス中空球体(グラスマイクロバルーン)、天然ガラスを膨張させた多泡構造のパーライトなどの無機質中空体、エクスパンセル、発泡ポリスチレン等の有機質中空体等が知られている。
これらガラス中空球体やパーライト等の不活性物質を混合すると、ポーラスプリル硝安粒子同士の隙間に入り、爆薬成分中に爆薬でない不活性成分の不連続部ができ、嵩比重は低下するとともに鈍感化する。
【０００８】
【発明が解決しようとする課題】
しかしながら、このようにして粒子が低密度化され、鋭敏になったポーラスプリル硝安（低比重ポーラスプリル硝安）を使用した硝安油剤爆薬は雷管起爆性を有するようになり、起爆感度試験にて６号雷管で完爆し、規格（ＪＩＳ−Ｋ−４８０１）を満足しなくなる。
【０００９】
硝安油剤爆薬は、ＪＩＳ−Ｋ−４８０１において、塩ビ雨樋法またはカートン法による起爆感度試験にて６号雷管で完爆しないことと規定されている。
【００１０】
また、製造直後の起爆感度試験で不爆であっても、ポーラスプリル硝安と燃料油の接触面積は時間の経過と共に拡大していくため、製造後数週間を経過すると雷管起爆性が向上し、完爆する虞がある。
【００１１】
また、不活性な物質の、ガラス中空球体は表面に細孔がないため硝安油剤爆薬の鈍感化剤として使用した場合、軽油がガラス中空球体内部に浸透せずガラス中空球体の表面に付着する。
そして、軽油の粘性によりガラス中空球体同士が接着し大きな固まりを形成してしまう。そのため、硝安油剤爆薬内に均一に分散しなくなってしまうという問題がある。均一に分散しないと硝安油剤爆薬の起爆性、伝爆性にバラツキが生じ、不爆または爆轟中断を起こす虞がある。
【００１２】
また、パーライトは、一般的に強度が弱いため硝安油剤爆薬製造時に或いは運搬時に粒子が崩れやすく粉塵が発生するという問題がある。
【００１３】
また、シラスバルーンは、火砕流などで形成された天然の多孔体であるが球状体でなく、形状にもバラツキがあり、粒径が０．５ｍｍ以下と極めて微細でガラスマイクロバルーン同様、軽油の粘性によりシラスバルーン同士が接着し大きな固まりを形成してしまう。そのため、硝安油剤爆薬内に均一に分散しなくなってしまうという問題がある。
【００１４】
本発明はこれらの問題を解決するために本発明で記すところの比重調節剤兼鈍感化剤を加えることによって、前述の様に粒子が低密度化され鋭敏になったポーラスプリル硝安を使用しても、製造直後のみならず製造後数週間経過後でも、６号雷管起爆で完爆しない（不完爆）鈍感化した硝安油剤爆薬を提供することにある。
【００１５】
また、本発明の他の目的は、低密度のポーラスプリル硝安を使用した硝安油剤爆薬の嵩比重を、さらに低下させると共に、嵩比重を調節できる通常硝安油剤爆薬を提供することにある。
【００１６】
また、本発明の他の目的は、嵩比重を低減した硝安油剤爆薬において、従来より少ない爆薬消費（重）量であっても、従来の発破と同等の破壊効果を得ることが出来る硝安油剤爆薬を提供することにある。
【００１７】
また、本発明の他の目的は、比重調節剤兼鈍感化剤を混合しても、製造及び取扱い中に、粉塵の発生がなく、かつ比重調節剤兼鈍感化剤が硝安油剤爆薬中に均一に分散する硝安油剤爆薬を提供することにある。
【００１８】
請求項１記載の発明は、嵩比重が０．６０〜０．８０および平均粒径が１．０〜１．５ｍｍのポーラスプリル硝酸アンモニウムと、燃料油と、燃料油を吸収する物性を有し形状が球体であり、かつ嵩比重が０．２〜０．３、平均粒径が１〜２ｍｍおよび硬度が１〜１５％である不活性な無機質多孔体の比重調節剤兼鈍感化剤とを混合してなる硝安油剤爆薬であって、前記無機質多孔体を硝安油剤爆薬全体の２〜１２重量％の範囲で含有し、硝安油剤爆薬製造直後及び当該製造２週間〜４週間経過後、硝安油剤爆薬の起爆感度試験で不完爆となることを特徴とする硝安油剤爆薬である。
特に、粒子が低密度化されたポーラスプリル硝安を使用することで雷管起爆性を有するようになった硝安油剤爆薬に、前記特定の比重調節剤兼鈍感化剤を混合することにより６号雷管起爆で不完爆となり、且つ硝安油剤爆薬製造直後及び当該製造２週間〜４週間経過後、硝安油剤爆薬の起爆感度試験で不完爆となることが分かった。また、この無機質多孔体は不活性であり、硝安油剤爆薬として混合した場合でも酸素バランスが、更にマイナスとならず安定した性能を得ることが分かった。
【００２１】
【発明の実施の形態】
以下、本発明の実施形態を詳細に説明する。
本発明の硝安油剤爆薬は、低比重のポーラスプリル硝安に、燃料油を吸収する物性を有する不活性な無機質多孔体（以下、吸油性不活性無機質多孔体と記載）を比重調整剤兼鈍感剤として添加し、さらに燃料油を混合する。
【００２２】
ポーラスプリル硝安と吸油性不活性無機質多孔体との混合物に燃料油を混合撹拌すると、吸油性不活性無機質多孔体は吸油性を有するので、燃料油を吸収する。
また、同時にポーラスプリル硝安も吸油性を有するので、燃料油を吸収する。
ここで、ポーラスプリル硝安と吸油性不活性無機質多孔体は、互いの吸油率において燃料油を吸収するため、ポーラスプリル硝安への吸油量は、無機質多孔体への吸油によって低下する。
【００２３】
また、用いる吸油性不活性無機質多孔体の嵩比重が低すぎたり、粒度が微細すぎると、ポーラスプリル硝安との比重差、粒度差により分離しやすくなり伝爆低下や、装填作業時に粉塵が舞いやすくなる虞がある。逆に嵩比重が高すぎると、比重低減等の効果が小さくなってしまう。
また、吸油性不活性無機質多孔体の粒径については、ポーラスプリル硝安との分離を起こしにくくするため、ポーラスプリル硝安の平均粒径に近いほど好ましい。
また、吸油性不活性無機質多孔体は、製造において取扱い時の粒子の破壊による粉塵の発生を防ぐため、ある程度の粒子強度（硬度）が必要であり、その硬度は使用するポーラスプリル硝安と同等か硬い方が好ましい。
【００２４】
そこで、吸油性不活性無機質多孔体は、例えば、嵩比重が０．２〜０．３、平均粒径が１〜２ｍｍ、硬度が１〜１５％であって、硝安油剤爆薬中、２−１２重量％の範囲、好ましくは２〜６重量％で配合すると良い。
また、このときのポーラスプリル硝安の平均粒径は、１．０〜１．５ｍｍの範囲、好ましくは１．２〜１．４ｍｍ、嵩比重は、粒子強度とともに必要な爆速を維持するため０．６０〜０．８０の範囲、好ましくは０．６５〜０．７５のものを使用すると良い。
【００２５】
吸油性不活性無機質多孔体の嵩比重は、吸油性不活性無機質多孔体をロートから容器に流し込み、容器に入った吸油性不活性無機質多孔体の重量と容器の容積から算出する。
吸油性不活性無機質多孔体の平均粒径は、吸油性不活性無機質多孔体を目開きの異なる数種類の篩に通し、その篩毎の重量比により算出する。
吸油性不活性無機質多孔体の硬度は、粒径１〜２ｍｍのものを篩により選別して試料とし、受け皿(内径２００ｍｍ)と挽き皿(外形１９６ｍｍ、重量１７１５ｇ)からなる硬度測定器に試料約４０ｃｃ(重量は測定しておく)を硬度測定器の受け皿に投入した後、その上に挽き皿を置き、挽き皿を１０秒間で５回転させる。その後受け皿の中の試料を目開き１ｍｍの篩に通し、篩を通過した試料(圧潰品)の重量を測定する。硬度は次の式により算出する。
硬度(%)＝圧潰品の重量(g)／受け皿に投入した試料の重量(g)×１００
【００２６】
本発明の硝安油剤爆薬は、吸油性不活性無機質多孔体の配合比を適正に変えることで、嵩比重を任意に調整することが可能となり、所望の性能を持った爆薬商品を得ることが可能となる。
【００２７】
本発明の硝安油剤爆薬に用いられる燃料油としては、２号軽油の外、灯油等の鉱物油、植物油、動物油、ワックス類等を用いても目的は達し得る。
また、本発明の硝安油剤爆薬は、必要に応じてハミング等の制電防止剤、グアーガム、澱粉等の増粘剤（粘稠剤）、或いはセメントとの反応を抑制するためリンゴ酸等の弱酸添加剤を加えることができる。
【００２８】
【作用】
上述のとおり、粒子が低密度化されたポーラスプリル硝安に、このポーラスプリル硝安よりも低い嵩比重の、燃料油を吸収する物性を有する不活性な比重調節剤兼鈍感化剤を添加する。そして、ここに燃料油を混合すると不活性物質と硝安両者に燃料油が吸収される。その結果、ポーラスプリル硝安の吸油量が相対的に低下し、その結果として酸化剤と燃料との接触面積が減少するので起爆性が鈍感化され、６号雷管で不完爆となる。
【００２９】
また、この硝安油剤爆薬は、比重調節剤兼鈍感化剤が硝安油剤爆薬内の粒子間に均一に分散するとともに低嵩比重となるので、同一発破坑内に占める爆薬容積を一定とするならば、従来より爆薬消費（重）量が少なくてすむ。
【００３０】
【実施例】
次に具体的な実施例を挙げて詳細に説明する。
実施例１
ポーラスプリル硝安（嵩比重０．６９、平均粒径１．３８ｍｍ）９２．１重量％と吸油性不活性無機質多孔体（嵩比重０．２３、平均粒径１．５０ｍｍ、硬度４．０％）２．０重量％を混合し、その後に燃料油として２号軽油５．９重量％を加えて硝安油剤爆薬を得た。
なお、本実施例で使用した吸油性不活性無機質多孔体は、ポラバー（DENNERT PORAVER GMBH社商標）である。
ポラバーの物性 (形状：球体、色：乳白色、粒径：１〜２ｍｍ、嵩比重：０．２３、主成分：二酸化ケイ素、水に不溶)
実施例２
ポーラスプリル硝安（実施例１のもの）８６．５重量％と吸油性不活性無機質多孔体（実施例１のもの）８．０重量％を混合し、その後に２号軽油５．５重量％を加えて硝安油剤爆薬を得た。
実施例３
ポーラスプリル硝安（嵩比重０．７３、平均粒径１．２０ｍｍ）９０．２重量％と吸油性不活性無機質多孔体（実施例１のもの）４．０重量％を混合し、その後に２号軽油５．８重量％を加えて硝安油剤爆薬を得た。
実施例４
ポーラスプリル硝安（嵩比重０．６２、平均粒径１．４２ｍｍ）９０．２重量％と吸油性不活性無機質多孔体（実施例１のもの）４．０重量％を混合し、その後に２号軽油５．８重量％を加えて硝安油剤爆薬を得た。
実施例５
ポーラスプリル硝安（嵩比重０．６２、平均粒径１．４２ｍｍ）８４．６重量％と吸油性不活性無機質多孔体（実施例１のもの）１０．０重量％を混合し、その後に２号軽油５．４重量％を加えて硝安油剤爆薬を得た。
【００３１】
比較例１
ポーラスプリル硝安（実施例１のもの）９４．０重量％と２号軽油６．０重量％を加えて硝安油剤爆薬を得た。
比較例２
ポーラスプリル硝安（実施例１のもの）９３．１重量％とガラス中空球体（嵩比重０．０８、平均粒径６５μｍ））１．０重量％を混合し、その後２号軽油５．９重量％を加えて硝安油剤爆薬を得た。
比較例３
ポーラスプリル硝安（実施例１のもの）９０．２重量％とパーライト（嵩比重０．１６、平均粒径１．００ｍｍ、硬度６６．７％）４．０重量％とを混合し、その後２号軽油５．８重量％を加えて硝安油剤爆薬を得た。
【００３２】
実施例１〜５、比較例１〜３で得られた硝安油剤爆薬について、嵩比重の測定、鋼管爆速測定(JIS K 4810で規定されているイオンギャップ法)、及び起爆感度試験(JIS K 4801、起爆感度試験方法Ａ：塩ビ雨樋法による)を実施した。
嵩比重は硝安油剤爆薬をロートから容器に流し込み、容器に入った硝安油剤爆薬の重量と容器の容積から算出した。
鋼管爆速はJIS G 3452に規定されている３２Ａ鋼管に硝安油剤爆薬を装填し、イオンギャップ法により爆速を測定した。なお、起爆には６号電気雷管を、伝爆薬として日本工機株式会社製含水爆薬エナマイト（登録商標）５０ｇを用いた。
起爆感度試験はJIS A 5706に規定されている硬質塩ビ雨樋に硝安油剤爆薬を入れ、６号雷管を挿入した後、これを起爆させ、硝安油剤爆薬が爆発したかどうかを導爆線により判定した。なお６号雷管は日本油脂株式会社製６号電気雷管を用いた。
これらの試験結果における、実施例１〜５を表１に、比較例１〜３を表２に示す。
【００３３】
【表１】

【００３４】
【表２】

【００３５】
実施例１〜５の本発明の爆薬が、製造後４週間を経過しても雷管起爆試験で不爆であった。
比較例１は吸油性不活性無機質多孔体を配合しない爆薬、比較例２は吸油性不活性無機質多孔体ではなく、ガラス中空球体を使用した爆薬、これらは製造後２週間を経過した時点で雷管起爆性を有した。
また、比較例３は、パーライトを使用した爆薬で、取り扱い時に粉塵が舞うという問題が発生した。
【００３６】
図１および図２は、本発明の硝安油剤爆薬に使用した実施例１〜５に記載の吸油性不活性無機質多孔体の配合比と嵩比重、吸油性不活性無機質多孔体の配合比爆速の関係を実験上から表したものである。
図１は吸油性不活性無機質多孔体の配合比と嵩比重の関係、図２は吸油性不活性無機質多孔体の配合比と爆速の関係を示す。
図中のポイントで示された部分は実測値であり、直線は最小二乗法により求めた回帰直線である。
【００３７】
図１に示すとおり、吸油性不活性無機質多孔体の配合比が増えると嵩比重は低下する。よって、吸油性不活性無機質多孔体の配合比を変えることにより、ある程度自由に嵩比重を変えることが可能となる。
しかし、図２に示すとおり、吸油性不活性無機質多孔体の配合量を増やすと、爆速は徐々に低下していき、ついには不爆となる。
だだし、吸油性無機質多孔体を添加した硝安油剤爆薬の爆速と起爆感度には相関性があり、爆速が低下するに従い、起爆感度も鈍感化する方向にあるため、吸油性不活性無機質多孔体の配合により、雷管起爆性が低下することになる。
【００３８】
【発明の効果】
本発明は、吸油性を有する不活性な多孔体を比重調節剤兼鈍感化剤として用いる（混合する）ので、嵩密度を低下させることができるとともに、６号雷管起爆で不完爆となり、またさらに製造後数週間経過後でも不完爆となる硝安油剤爆薬を得ることができる。
【００３９】
また、低嵩比重および鈍感化した本発明の硝安油剤爆薬は、発破効果を落とすことなく2500ｍ／ｓ以上の所望の爆速を得ることができ、従来より少ない爆薬消費（重）量であっても十分な破壊効果を有する。
【図面の簡単な説明】
【図１】本発明の硝安油剤爆薬の吸油性不活性無機質多孔体の配合比と嵩比重との関係を示す。
【図２】本発明の硝安油剤爆薬の吸油性不活性無機質多孔体の配合比とＪＩＳ鋼管爆速との関係を示す。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an explosive for industrial use used in construction industry, crushed stone, mining, and the like, as an explosive for industrial use.
[0002]
[Prior art]
An ammonium nitrate explosive is composed of 94% by weight of porous prill ammonium nitrate (hereinafter referred to as porous prill ammonium nitrate) and 6% by weight of light oil, and is a granular explosive with high safety, low cost and good fluidity. Because it has many advantages, such as being able to load, it is consumed in large quantities compared to other industrial explosives.
As a method of reducing the cost of consumption of a salt explosive explosive, it is natural to reduce the price of the salt explosive explosive, but as another method, if the bulk specific gravity of the salt explosive explosive is reduced, the power is almost the same. When loaded in the charge hole (bore hole), the explosive cost in the blasting operation can be reduced by reducing the use weight of the ammonium nitrate explosive per unit volume of the charge hole.
[0003]
Therefore, in the past, porous prill ammonium which has reduced the density of the ammonium nitrate particles itself, for example, by improving the degree of porosity, or by reducing the density by containing a foaming agent in the particles, the bulk specific gravity of the obtained ammonium oil explosive explosive is reduced. We have been trying to reduce it.
In addition, if the weight of use of the ammonium explosive explosive per unit volume of the borehole is reduced, there is a concern that the crushing effect will be reduced. However, the porous prill ammonium sulfate that has improved the degree of porosity and increased the specific surface area to reduce the particle density. Since the reactivity of the salt oil explosive was improved by use, it was found that even if the amount of the salt oil explosive was slightly reduced, the crushing effect at the blasting site was hardly affected.
[0004]
Porous prill ammonium nitrate is a porous sphere having a large number of continuous voids inside the particles, and when mixed with fuel oil, the fuel oil penetrates and adsorbs into the voids.
As described above, the porous prill ammonium nitrate with a reduced particle density (with a bulk specific gravity of about 0.75 or less) has a larger particle size than a porous prill ammonium nitrate with a normal density (with a bulk specific gravity of about 0.80 or more). In addition, since the voids are large and the specific surface area is large, the density of particles is reduced and the absorbability of fuel oil is inevitably improved.
Since the fuel oil absorbability is thus improved, the contact area between porous prill ammonium nitrate, which is an oxidant component, and the fuel oil increases.
The explosion reaction of the ammonium nitrate explosive is a redox reaction on the surface at the contact surface between the fuel oil and the porous prill ammonium nitrate.
Therefore, as a matter of course, the larger the contact area between the porous prill ammonium nitrate and the fuel oil, the better the reactivity.
That is, by reducing the particle density of the porous prill ammonium nitrate as described above (increasing the specific surface area), the reactivity of the ammonium nitrate explosive using this porous prill ammonium nitrate is improved.
[0005]
According to experiments, the porous prill ammonium sulfate with a large specific surface area obtained in this way has a very strong possibility of having a No. 6 detonator initiation performance when the bulk specific gravity is below 0.7.
[0006]
Low specific gravity porous prill ammonium nitrate with a large specific surface area has improved reactivity as described above, so that the explosion speed is increased and the power is improved, but at the same time the sensitivity becomes sharp.
[0007]
Therefore, in order to make this insensitive, there is a method in which an inert substance is mixed with the ammonium nitrate explosive.
By mixing an inert substance, the reactivity of the ammonium nitrate explosive is reduced and desensitized. Moreover, when using this inactive substance, if the bulk specific gravity is lower than that of the ammonium nitrate explosive, the bulk specific gravity of the ammonium nitrate explosive can be further reduced.
Examples of the inert substance used include, for example, glass hollow spheres (glass microballoons), inorganic hollow bodies such as perlite having a multi-bubble structure in which natural glass is expanded, and organic hollow bodies such as expand cells and expanded polystyrene. It has been known.
When these inert substances such as glass hollow spheres and pearlite are mixed, they enter the gaps between the porous prill ammonium particles, creating discontinuous portions of inert components that are not explosives in the explosive component, and the bulk specific gravity is lowered and desensitized. .
[0008]
[Problems to be solved by the invention]
However, the desulfurization explosives using porous prill ammonium nitrate (low specific gravity porous prill ammonium nitrate), whose particles have been reduced in density in this way, have become detonating, and No. 6 in the explosion sensitivity test. The detonator completes the explosion and does not satisfy the standard (JIS-K-4801).
[0009]
In JIS-K-4801, it is stipulated that the explosive for explosives of ammonium nitrate does not completely explode in the No. 6 detonator in the initiation sensitivity test by the PVC rain gutter method or the carton method.
[0010]
In addition, even if there is no explosion in the initiation sensitivity test immediately after production, the contact area between porous prill ammonium nitrate and fuel oil expands over time, so the detonator initiation performance improves after a few weeks after production, There is a risk of complete explosion.
[0011]
In addition, since the glass hollow sphere, which is an inactive substance, has no pores on the surface, when used as a desensitizing agent for an ammonium nitrate explosive, light oil does not penetrate into the glass hollow sphere and adheres to the surface of the glass hollow sphere.
And the glass hollow spheres adhere to each other due to the viscosity of the light oil and form a large mass. Therefore, there exists a problem that it will not disperse | distribute uniformly within a salt oil explosive explosive. If it is not uniformly dispersed, the explosive and explosive properties of the smelting agent explosives will vary, and there is a risk of causing no explosion or detonation interruption.
[0012]
In addition, since pearlite generally has low strength, there is a problem that particles are easily broken during production of the ammonium nitrate explosive explosive or during transportation, and dust is generated.
[0013]
Shirasu Balloon is a natural porous body formed by pyroclastic flow, etc., but it is not spherical, has a variation in shape, and is very fine with a particle size of 0.5 mm or less. As a result, the shirasu balloons are bonded together to form a large mass. Therefore, there exists a problem that it will not disperse | distribute uniformly within a salt oil explosive explosive.
[0014]
In order to solve these problems, the present invention uses a porous prill ammonium nitrate in which particles are reduced in density and sharpened as described above by adding the specific gravity adjusting agent and desensitizing agent described in the present invention. Another object of the present invention is to provide a desensitized nitrate oil explosive that does not completely explode (incomplete explosion) due to the detonation of No. 6 detonator not only immediately after production but also several weeks after production.
[0015]
Another object of the present invention is to provide a normal ammonium nitrate explosive capable of further reducing the bulk specific gravity of a ammonium explosive explosive using low-density porous prill ammonium nitrate and adjusting the bulk specific gravity.
[0016]
In addition, another object of the present invention is to provide an ammonium nitrate explosive capable of obtaining a destructive effect equivalent to that of conventional blasting even if the explosive consumption (heavy) amount is smaller than that of conventional explosives with reduced bulk specific gravity. Is to provide.
[0017]
Another object of the present invention is that even if a specific gravity adjusting agent / desensitizing agent is mixed, no dust is generated during the production and handling, and the specific gravity adjusting agent / desensitizing agent is uniform in the ammonium nitrate oil explosive. It is to provide an anti-nitrile explosive that is dispersed in the water.
[0018]
The invention according to claim 1 is a porous prill ammonium nitrate having a bulk specific gravity of 0.60 to 0.80 and an average particle diameter of 1.0 to 1.5 mm, a fuel oil, and a physical property that absorbs the fuel oil. Is a sphere, mixed with a specific gravity regulator / desensitizing agent for an inert inorganic porous body having a bulk specific gravity of 0.2 to 0.3, an average particle diameter of 1 to 2 mm, and a hardness of 1 to 15%. A mineral oil explosive comprising the inorganic porous material in a range of 2 to 12% by weight of the total amount of the ammonium nitrate explosive, immediately after the manufacture of the ammonium explosive explosive and after 2 to 4 weeks of the production, This is an explosive of ammonium nitrate oil characterized by incomplete explosion in the initiation sensitivity test .
In particular, detonation of No. 6 detonator by mixing the specific gravity control agent and desensitizing agent into the detonation explosive that has been detonated by using porous prill ammonium with reduced particle density. The incomplete explosion occurred immediately after the manufacture of the explosive explosive and after 2 to 4 weeks after the production, the explosive sensitivity test of the explosive explosive was found to be incomplete . Further, the inorganic porous body is an inert, oxygen balance even when mixed as ammonium nitrate fuel oil explosive was found that further provides stable performance as well as negative.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail.
The explosive of the present invention comprises an inert inorganic porous material having physical properties that absorbs fuel oil (hereinafter referred to as an oil-absorbing inactive inorganic porous material) in a low specific gravity porous prill ammonium nitrate. And then add fuel oil.
[0022]
When fuel oil is mixed and stirred in a mixture of porous prill ammonium nitrate and an oil-absorbing inert inorganic porous material, the oil-absorbing inert inorganic porous material absorbs fuel oil because the oil-absorbing inert inorganic porous material has oil-absorbing properties.
At the same time, porous prill ammonium nitrate also absorbs fuel oil because it has oil absorption.
Here, since the porous prill ammonium nitrate and the oil-absorbing inert inorganic porous material absorb the fuel oil at the mutual oil absorption rate, the oil absorption amount to the porous prill ammonium nitrate is reduced by the oil absorption to the inorganic porous material.
[0023]
Also, if the bulk density of the oil-absorbing inert inorganic porous material used is too low or the particle size is too fine, it will be easily separated due to the difference in specific gravity and particle size from porous prill ammonium nitrate, resulting in reduced explosion and dust during the loading operation. May be easier. On the other hand, when the bulk specific gravity is too high, effects such as specific gravity reduction are reduced.
Further, the particle diameter of the oil-absorbing inert inorganic porous material is preferably closer to the average particle diameter of porous prill ammonium nitrate in order to prevent separation from porous prill ammonium nitrate.
In addition, the oil-absorbing inert inorganic porous material requires a certain level of particle strength (hardness) to prevent dust generation due to particle breakage during handling, and is the hardness equivalent to the porous prill ammonium used? Harder is preferable.
[0024]
Therefore, the oil-absorbing inert inorganic porous material has, for example, a bulk specific gravity of 0.2 to 0.3, an average particle diameter of 1 to 2 mm, and a hardness of 1 to 15%. It is good to mix | blend in the range of weight%, Preferably it is 2 to 6 weight%.
Further, the average particle size of the porous prill ammonium nitrate at this time is in the range of 1.0 to 1.5 mm, preferably 1.2 to 1.4 mm, and the bulk specific gravity is 0.00 in order to maintain the necessary explosion speed together with the particle strength. A range of 60 to 0.80, preferably 0.65 to 0.75 may be used.
[0025]
The bulk specific gravity of the oil-absorbing inert inorganic porous material is calculated from the weight of the oil-absorbing inert inorganic porous material poured into the container by pouring the oil-absorbing inert inorganic porous material into the container from the funnel.
The average particle diameter of the oil-absorbing inert inorganic porous material is calculated by passing the oil-absorbing inert inorganic porous material through several kinds of sieves having different openings and calculating the weight ratio of each sieve.
The hardness of the oil-absorbing inert inorganic porous material is selected from a sample having a particle diameter of 1 to 2 mm using a sieve, and the sample is placed on a hardness measuring instrument consisting of a saucer (inner diameter 200 mm) and a grinder (outer diameter 196 mm, weight 1715 g). After 40 cc (weigh the weight) is put into the saucer of the hardness tester, a grinding pan is placed on it and the grinding pan is rotated 5 times for 10 seconds. Thereafter, the sample in the tray is passed through a sieve having an opening of 1 mm, and the weight of the sample (crushed product) that has passed through the sieve is measured. The hardness is calculated by the following formula.
Hardness (%) = weight of crushed product (g) / weight of sample put in tray (g) × 100
[0026]
According to the present invention, an explosive product with desired performance can be obtained by appropriately changing the blending ratio of the oil-absorbing inert inorganic porous material, and the bulk specific gravity can be arbitrarily adjusted. It becomes.
[0027]
As the fuel oil used in the ammonium nitrate explosive of the present invention, the object can be achieved by using mineral oil such as kerosene, vegetable oil, animal oil, waxes, etc. in addition to No. 2 diesel oil.
In addition, the anti-nitrite explosive of the present invention is a weak acid such as malic acid in order to suppress reaction with antistatic agents such as humming, thickeners such as guar gum and starch, or cement as necessary. Additives can be added.
[0028]
[Action]
As described above, an inert specific gravity adjusting agent / desensitizing agent having physical properties for absorbing fuel oil having a bulk specific gravity lower than that of the porous prill ammonium nitrate is added to the porous prill ammonium nitrate whose particles are reduced in density. And if fuel oil is mixed here, fuel oil will be absorbed into both an inert substance and ammonium nitrate. As a result, the oil absorption of the porous prill ammonium nitrate is relatively lowered, and as a result, the contact area between the oxidant and the fuel is reduced, so that the initiation performance is desensitized, and the No. 6 detonator has an incomplete explosion.
[0029]
In addition, since the specific gravity regulator and desensitizing agent is uniformly dispersed among the particles in the safe oil explosive and has a low bulk specific gravity, if the explosive volume occupying the same blast mine is constant, Less explosive consumption (heavy) than before.
[0030]
【Example】
Next, specific examples will be given and described in detail.
Example 1
Porous prill ammonium nitrate (bulk specific gravity 0.69, average particle size 1.38 mm) 92.1% by weight and oil-absorbing inert inorganic porous material (bulk specific gravity 0.23, average particle size 1.50 mm, hardness 4.0%) After mixing 2.0% by weight, 5.9% by weight of No. 2 diesel oil was added as a fuel oil to obtain a nitrate oil explosive.
In addition, the oil-absorbing inert inorganic porous material used in the present example is PORABAR (trademark of DENNERT PORAVER GMBH).
Physical properties of polar rubber (shape: sphere, color: milky white, particle size: 1-2 mm, bulk specific gravity: 0.23, main component: silicon dioxide, insoluble in water)
Example 2
86.5% by weight of porous prill ammonium nitrate (from Example 1) and 8.0% by weight of an oil-absorbing inert inorganic porous material (from Example 1) were mixed, followed by 5.5% by weight of No. 2 diesel oil. In addition, we obtained an explosive of ammonium nitrate.
Example 3
Porous prill ammonium nitrate (bulk specific gravity 0.73, average particle size 1.20 mm) 90.2 wt% and oil-absorbing inert inorganic porous material (Example 1) 4.0 wt% were mixed, then No. 2 A 5.8% by weight of light oil was added to obtain a salt oil explosive.
Example 4
Porous prill ammonium nitrate (bulk specific gravity 0.62, average particle diameter 1.42 mm) 90.2% by weight and oil-absorbing inert inorganic porous material (Example 1) 4.0% by weight were mixed, and then No. 2 A 5.8% by weight of light oil was added to obtain a salt oil explosive.
Example 5
Porous prill ammonium nitrate (bulk specific gravity 0.62, average particle size 1.42 mm) 84.6% by weight and oil-absorbing inert inorganic porous material (of Example 1) 10.0% by weight were mixed, and then No. 2 Addition of 5.4% by weight of light oil provided a nitrate oil explosive.
[0031]
Comparative Example 1
Porous prill ammonium nitrate (of Example 1) 94.0% by weight and No. 2 gas oil 6.0% by weight were added to obtain an ammonium nitrate oil explosive.
Comparative Example 2
Porous prill ammonium nitrate (from Example 1) 93.1% by weight and glass hollow sphere (bulk specific gravity 0.08, average particle size 65 μm) 1.0% by weight were mixed, then No. 2 light oil 5.9% by weight Was added to obtain an explosive of the ammonium nitrate oil explosive.
Comparative Example 3
Porous prill ammonium nitrate (of Example 1) 90.2% by weight and pearlite (bulk specific gravity 0.16, average particle size 1.00mm, hardness 66.7%) 4.0% by weight were mixed, then No. 2 A 5.8% by weight of light oil was added to obtain a salt oil explosive.
[0032]
For the ammonium nitrate explosives obtained in Examples 1 to 5 and Comparative Examples 1 to 3, measurement of bulk specific gravity, steel tube explosion speed measurement (ion gap method defined in JIS K 4810), and initiation sensitivity test (JIS K 4801) Initiation sensitivity test method A: PVC rain gutter method).
The bulk specific gravity was calculated from the weight of the salt oil explosive charged in the container and the volume of the container by pouring the salt oil explosive from the funnel into the container.
As for the steel tube explosion speed, a 32A steel pipe specified in JIS G 3452 was loaded with a salt oil explosive, and the explosion speed was measured by the ion gap method. In addition, No. 6 electric detonator was used for detonation, and 50 g hydrous explosive enamel (registered trademark) manufactured by Nippon Koki Co., Ltd. was used as an explosive agent.
Initiation sensitivity test is conducted by inserting a nitric acid explosive explosive into a hard PVC rain gutter stipulated in JIS A 5706, inserting a No. 6 detonator, detonating it, and judging whether or not the explosive explosive has expelled it. did. The No. 6 detonator was a No. 6 electric detonator manufactured by NOF Corporation.
In these test results, Examples 1 to 5 are shown in Table 1, and Comparative Examples 1 to 3 are shown in Table 2.
[0033]
[Table 1]

[0034]
[Table 2]

[0035]
The explosives of the present invention of Examples 1 to 5 were unexplosive in the detonator initiation test even after 4 weeks had passed since manufacture.
Comparative Example 1 is an explosive that does not contain an oil-absorbing inert inorganic porous material, and Comparative Example 2 is an explosive that uses glass hollow spheres instead of an oil-absorbing inert inorganic porous material. It was detonating.
Further, Comparative Example 3 was an explosive using pearlite, and there was a problem that dust flew during handling.
[0036]
FIG. 1 and FIG. 2 show the mixing ratio and bulk specific gravity of the oil-absorbing inert inorganic porous material described in Examples 1 to 5 used in the nitrate oil explosive of the present invention, and the mixing specific explosion speed of the oil-absorbing inert inorganic porous material. The relationship is expressed experimentally.
FIG. 1 shows the relationship between the blending ratio of the oil-absorbing inert inorganic porous material and the bulk specific gravity, and FIG. 2 shows the relationship between the blending ratio of the oil-absorbing inert inorganic porous material and the explosion speed.
The portion indicated by the point in the figure is an actual measurement value, and the straight line is a regression line obtained by the least square method.
[0037]
As shown in FIG. 1, the bulk specific gravity decreases as the blending ratio of the oil-absorbing inert inorganic porous material increases. Therefore, the bulk specific gravity can be freely changed to some extent by changing the blending ratio of the oil-absorbing inert inorganic porous material.
However, as shown in FIG. 2, when the blending amount of the oil-absorbing inert inorganic porous material is increased, the explosion speed gradually decreases and eventually becomes unexplosive.
However, there is a correlation between the explosion speed and initiation sensitivity of the explosives with added oil-absorbing inorganic porous material, and as the explosion speed decreases, the initiation sensitivity tends to be desensitized. The detonator detonability will be reduced by the blending of.
[0038]
【The invention's effect】
The present invention uses (mixes) an inert porous body having oil absorbency as a specific gravity adjusting agent and desensitizing agent, so that the bulk density can be reduced, and the detonation of No. 6 detonator causes an incomplete explosion. Furthermore, it is possible to obtain a nitrate oil explosive that causes an incomplete explosion even after several weeks have passed since manufacture.
[0039]
In addition, the low bulk specific gravity and insensitive depressurized explosive of the present invention can obtain a desired explosive speed of 2500 m / s or more without deteriorating the blasting effect. Has a sufficient destructive effect.
[Brief description of the drawings]
FIG. 1 shows the relationship between the blending ratio and bulk specific gravity of an oil-absorbing inert inorganic porous material of the ammonium nitrate explosive of the present invention.
FIG. 2 shows the relationship between the blending ratio of the oil-absorbing inert inorganic porous body of the ammonium nitrate explosive of the present invention and the JIS steel pipe explosion speed.

Claims

Bulk specific gravity is 0.60 to 0.80 and an average particle size of 1.0~1.5mm porous prill ammonium nitrate, fuel oil, the shape have a property to absorb fuel oil is a sphere, and the bulk specific gravity 0.2 to 0.3, an average particle diameter of 1 to 2 mm, and a hardness of 1 to 15%. An inert mineral porous body specific gravity regulator / desensitizing agent is mixed with an anti-nitrile oil explosive. In addition, the inorganic porous material is contained in the range of 2 to 12% by weight of the total amount of the ammonium nitrate explosive. An explosive of ammonium nitrate, characterized by