JP3694503B2

JP3694503B2 - Deposit transport mechanism and deposit transport method

Info

Publication number: JP3694503B2
Application number: JP2002334274A
Authority: JP
Inventors: 良明土屋; 源治横森; 勉杉山; 晃久福本; 将人浦上; 光國吉川; ▲より▼州渋谷
Original assignee: Shinshu University NUC
Current assignee: Shinshu University NUC
Priority date: 2002-11-18
Filing date: 2002-11-18
Publication date: 2005-09-14
Anticipated expiration: 2022-11-18
Also published as: CN1259487C; ZA200405168B; JP2004169337A; US20050076545A1; TW200413607A; CN1602379A; AU2003242358A8; AU2003242358A1; KR20040101995A; KR100574133B1; WO2004046466A1

Description

【０００１】
【発明の属する技術分野】
本発明は堆積物搬送機構および堆積物搬送方法に関する。
【０００２】
【従来の技術】
浚渫機構として特許第３２７７４８９号に示される機構がある。
この浚渫機構は、
排出管を、貯水場所の水位よりも低い位置に設けた堰堤孔部を貫通させて配置すると共に、該排出管を、貯水場所に浮かべられた台船により、貯水場所の水位よりも低い位置に位置するように吊持し、
前記台船に設けられた昇降装置によって、排出管を、吸い込み口が貯水場所の水底面に対して所要のサイクルで接離するように上下動させて、脈動する吸込流である脈動流を得ると共に、堆積物が高い濃度で混合された流れと低い濃度で混合された流れとを交互に発生させるプラグ流を得るようにしたものである。
この浚渫機構によれば、堆積物を排出管の管壁に実質的に抵抗となるように接触させることなく、固液二相流として効率よく排出することができる。
【０００３】
【特許文献１】
特許第３２７７４８９号公報（特許請求の範囲）
【０００４】
【発明が解決しようとする課題】
本発明は、上記従来の浚渫機構にも応用でき、さらに効率よく堆積物を搬送できる堆積物搬送機構および堆積物搬送方法を提供することを目的とする。
【０００５】
【課題を解決するための手段】
本発明は上記目的を達成するため次の構成を備える。
すなわち、本発明に係る堆積物搬送機構は、貯水場所における堆積物が堆積した水底面に対向して開口された吸込口部、該吸込口部から鉛直方向へ延びる鉛直管部、および該鉛直管部上部から横方向にほぼ水平に延び、貯水場所よりも低位にある放出部に向けて開口された水平管部を有し、該水平管部が前記貯水場所の水位よりも低い位置に設けられた孔部を液密に貫通するように配置されると共に、貯水場所内の水中に動水勾配線よりも下方となる位置に支持され、さらに、堆積物の搬送時、昇降装置により、前記吸込口部が貯水場所の水底面に対して所要のサイクルで接離するように上下動される搬送管と、前記搬送管の吸込口部に設けられ、該吸込口部が上下方向に移動可能に進入する、下方に開放された形状をなすカップ状体と、該カップ状体内に水蒸気を供給する水蒸気供給部と、前記カップ状体内に圧縮気体を供給する圧縮気体供給部とを具備することを特徴としている。
そして、前記カップ状体と共に前記吸込口部側が下降され、吸込口部が水底面に食い込んで該吸込口部が急閉塞されることによって、前記搬送管内の流体の慣性力により吸込口部側の圧力が低下して膨張波が発生し、搬送管内の低濃度部に吸込口部側より順次、固体表面の低圧部で発生した水蒸気で水柱分離が発生し、次いで前記カップ状体に対して吸込口部が上昇され、吸込口に進入した高濃度部がプラグとして吸引されると共に、前記圧縮気体供給部から少量の圧縮気体が前記カップ状体内に供給され、前記水蒸気供給部から圧縮気体よりも大量の水蒸気が前記カップ状体内に供給されることによって、水底の高濃度の堆積物、カップ状体内の水、圧縮気体および水蒸気が吸込口部内に流入して、高濃度の堆積物からなるプラグおよび圧縮気体と水蒸気よりなるガスプラグが形成されて前記鉛直管部を上昇し、次いで前記カップ状体が上昇され、前記圧縮気体および水蒸気の供給が停止されることによって、ガスプラグ部の水蒸気が凝縮し、ガスプラグの体積が減少し、前記吸込口部が急開され、これにより吸込口部内に清水が流入され、吸込口部側の圧力が上昇して圧力波が発生し水柱分離部を凝縮させるサイクルが繰り返されることによって、前記搬送管内に、固・液・気よりなる連成振動子状流れを作り出して堆積物を前記放出部に搬出することを特徴としている。
高粘着力のある流体（ビンガム流体）の場合、管壁や固体表面に厚い流体膜が付着し、流れにくくなるが、本発明では、上記構成により、この流体膜の粘着力発生構造を、水柱分離部のキャビテーションによる激しい振動による剪断力で低下させ（チキソトロピー効果）、さらに流体膜中に生じた微小ガス流（マイクロバルーン）が分散したエマルション流れ（エマルション状の流れ）のキャビテーションによる局所的高圧力により、固体と固体を接触させることなく、固体間に流体を介在させ、常に流体膜を流体潤滑状態の動摩擦係数状態に保ち、高密度、高粘着力体積物であっても高効率で搬送することを可能とする。
【０００６】
また、本発明では、前記圧縮気体供給部が、圧縮空気もしくは炭酸ガスを供給することを特徴とする。
前記貯水場所に浮かべられる台船を有し、該台船に、前記搬送管を支持する吊持装置と、該搬送管を、前記吸込口部が水底面に対して所要のサイクルで接離するように上下動させる昇降装置と、前記水蒸気供給部と、前記圧縮気体供給部が配置されていることを特徴とする。
また、前記搬送管内と連通して設けられ、搬送管内のウォーターハンマーによる激しい圧力の増減を吸収する圧力吸収部を設けると好適である。
【０００７】
また本発明に係る堆積物搬送方法では、貯水場所における堆積物が堆積した水底面に対向して開口された吸込口部、該吸込口部から鉛直方向へ延びる鉛直管部、および該鉛直管部上部から横方向にほぼ水平に延び、貯水場所よりも低位にある放出部に向けて開口された水平管部を有し、該水平管部が前記貯水場所の水位よりも低い位置に設けられた孔部を液密に貫通するように配置されると共に、貯水場所内の水中に動水勾配線よりも下方となる位置に支持され、さらに、堆積物の搬送時、昇降装置により、前記吸込口部が貯水場所の水底面に対して所要のサイクルで接離するように上下動される搬送管と、前記搬送管の吸込口部に設けられ、該吸込口部が上下方向に移動可能に進入する、下方に開放された形状をなすカップ状体と、該カップ状体内に水蒸気を供給する水蒸気供給部と、前記カップ状体内に圧縮気体を供給する圧縮気体供給部とを具備する堆積物搬送機構を用い、前記カップ状体と共に前記吸込口部側を下降させ、吸込口部を水底面に食い込ませて該吸込口部を急閉塞することによって、前記搬送管内の流体の慣性力により吸込口部側の圧力を低下させて膨張波を発生させ、搬送管内の低濃度部に吸込口部側より順次水柱分離を発生させ、次いで前記カップ状体に対して吸込口部を上昇させ、吸込口に進入した高濃度部をプラグとして吸引させると共に、前記圧縮気体供給部から少量の圧縮気体を前記カップ状体内に供給し、前記水蒸気供給部から圧縮気体よりも大量の水蒸気を前記カップ状体内に供給することによって、水底の高濃度の堆積物、カップ状体内の水、圧縮気体および水蒸気を吸込口部内に流入させて、高濃度の堆積物からなるプラグおよびガスプラグを形成して前記鉛直管部を上昇させ、次いで前記カップ状体を上昇させ、前記圧縮気体および水蒸気の供給を停止することによって、ガスプラグ部の水蒸気を凝縮させ、ガスプラグの体積を減少させ、前記吸込口部を急開し、これにより吸込口部内に清水を流入させ、吸込口部側の圧力を上昇させて圧力波を発生させ水柱分離部を凝縮させるサイクルを繰り返すことによって、前記搬送管内に、固・液・気よりなる連成振動子状流れを作り出して堆積物を前記放出部に搬出することを特徴としている。
また、前記圧縮気体供給部から、圧縮空気もしくは炭酸ガスを前記カップ状体内に供給することを特徴とする。
【０００８】
【発明の実施の形態】
以下、本発明の好適な実施の形態を添付図面に基づいて詳細に説明する。
図１は、堆積物搬送機構の一例としての浚渫機構を示す断面図である。
この浚渫機構は巨大なダム湖に適用した例を示す。
１０は長い搬送管たる排出管であり、土砂等の堆積物２２が堆積したダム湖等の貯水場所２０の水底（湖底２９）に対向して開口された吸込口部１２と、その吸込口部１２から鉛直上方に延びる鉛直管部１３と、鉛直管部１３上部から横方向にほぼ水平に延び、貯水場所２０よりも低位にあるバイパストンネル等の放出部（放出水路）３０に開口する吐出口１８を有する水平管部１４とを具備する。
【０００９】
図２は、長野県にある美和ダムにおけるバイパストンネルの機構を示す。
ダム堤３１の上流側に、分派堤３３と貯砂ダム３４とを設けてある。貯砂ダム３４と分派堤３３では、粗い土砂を堰き止め、下流のダム湖に流入する固体量を低下させ、かつ沈積した固体を洪水後に取り出すことを容易にする。これら粗い土砂は、これまでのように機械的に運び出され、コンクリートの材料などに有効利用される。
洪水時には、分派堤３３近くに設けたバイパス水路（図示せず）のゲート（図示せず）をあけ、細かい土砂（直径がおよそ０．１ｍｍ程度）を洪水と共にバイパス水路を経てバイパストンネル３０に流し、細かい土砂がダム湖に堆積しないようにする。したがって、ダム湖には主としてウォッシュロードと称する極めて粒径の小さな堆積物が堆積することになる。
【００１０】
本実施の形態では、バイパストンネル３０に通じる補助トンネル（補助水路）３２を利用して、浚渫した堆積物を排出する。
前記排出管１０の排出端側は、この補助トンネル３２内に堰堤孔部２４を通じて導かれる。
【００１１】
堰堤孔部２４は、貯水場所２０の水位２１よりも低い位置を排出管１０が通るように、貯水場所２０の堰堤２５に開口して設けられている。
排出管１０の鉛直管部１３の上部でほぼ直角に曲げられてほぼ水平方向に延びる水平管部（堰堤孔部２４側が若干低くなるように設定される）１４は、堆積物の排出時、水中であって、動水勾配線よりも下方となる位置を通るように配置される。
これにより、水頭差エネルギーによって、排出管１０内を水流が満たされた状態で流下することとなる（清水の場合）。
清水とは、ρ（平均密度）≦１．０４４の場合のニュートン流体とみなされるものをいう（長野県の美和ダム湖底粘土浚渫の場合）。
なお、１．５＞ρ＞１．０４４の場合を高濃度流体といい、ビンガム流体的特性を示す。粘性の高いものを特にビンガム流体という。また、固相率３０％以上の場合には、ρ≧１．５となり、粘土の場合を塑性流体といい、固体相の集中している部分（プラグ）が間欠的に存在している場合をプラグ流という。プラグ流の場合、プラグの表面にカプセルのような粘土の膜（流体膜）ができる場合があり、これをカプセル流体という。
【００１２】
堰堤孔部２４では、水密構造にする必要があるが、この構造を図３により説明する。
４２はローラ状の受部材であり、堰堤孔部２４内に複数個配設され、排出管１０を軸線方向に滑らかに移動可能に受けている。
５０はシール部材であり、例えばゴム材でエアバック状に形成されていて、内部に空気が注入されている。このシール部材５０は、堰堤孔部２４と排出管１０との間（排出管１０の上下）に配設され、堰堤孔部２４と排出管１０との間を液密にシールする。
【００１３】
シール部材５０内の空気を抜くことで、排出管１０への締め付けが解除され、排出管１０は軸方向に移動可能となる。
上記受部材４２は、堰堤の躯体４４上に、シール部材５０を挟む両側に配設されている。
５２は水門板である。水門板５２は、堰堤部２５（図１）に上下方向に設けた溝部５３（図１）内に移動可能に配設され、動力によって上下駆動され、水門（堰堤孔部２４）を開閉できるようになっている。
水門板５２を下降させ、シール部材５０を介して排出管１０を挟むことで堰堤孔部２４を液密にシールする。
【００１４】
次に、３６は台船であり（図１）、クレーン３７が配設され、クレーン３７によって、排出管１０を鉛直管部１３が鉛直となるように、また水平管部１４が動水勾配よりも下方となるように吊り下げている。鉛直管部１３と水平管部１４との間の曲折部も水中に位置する。クレーン３７によって、自在に排出管１０の吊り下げ位置を変更することができる。
また、図４に示すように、台船３６上には、鉛直管部１３、したがって吸込口部１２を上下動させる昇降装置３８を備える。昇降装置は、鉛直管部１３に連結したチエーン６２を上下動させるように、例えばクランク装置で構成され、クレーン３７によって吊り下げられている排出管１０を、その鉛直管部１３を約２ｍ程度持ち上げて後、鉛直管部１３を自然落下させるように構成されている。
【００１５】
昇降装置はクランク装置に限られず、鉛直管部１３を上下動させ得るものならばよい。昇降装置の駆動部（図示せず）は、モータやシリンダ装置等を採用できる。
また、クレーン３７でなくとも、排出管１０を上記のように吊り下げることができるものであればよい。
また、台船３６ではなく、場合によってはダム湖内に、支持台（図示せず）を立設し、この支持台により排出管１０を支持したり、支持台上に昇降装置を設けてもよい。
この排出管１０を支持する支持台としては、水中に浮かぶフロート（図示せず）に構成してもよい。フロート内にエアーを給排して排出管１０の高さ調節ができるようにする。また、この場合に、フロートに水密の電動モータ（図示せず）を取り付け、この電動モータにより鉛直管部１３を上下動させるようにする。電動モータへの電気の供給は漏電を避けるためにフロートへのエア供給管（図示せず）の中に沿わせて設けた配線（図示せず）より行うようにする。
【００１６】
次に、図５は吸込口１２部分の一例を詳細に示す説明図である。
図５に示されるように、吸込口部１２は内筒（排出管１０）とカップ状体６０との二重筒構造となっている。
カップ状体６０は上端側が蓋６１によって閉塞されてカップ状をなし、排出管１０の下端部（以下内筒ということがある）が、この蓋６１を上下動自在に、液密、かつ気密に貫通して、カップ状体６０内に進入している。カップ状態６０の若干上方となる排出管１０の部位に連結具６２が固定されていて、この連結具６２にチエーン６３が連結され、チエーン６３が上記昇降装置に連繋されることによって、排出管１０が昇降可能となっている。
【００１７】
カップ状体６０は、液密状態で、内筒１０に対して相対的に上下動自在になっている。カップ状体６０の蓋６１と連結具６２との間がコイルスプリング６５で連結され、このコイルスプリング６５の伸縮する範囲でカップ状体６０が内筒１０に対して移動する。したがって、内筒１０が水底よりも上方に引き上げられているときは、カップ状体６０はコイルスプリング６５が延びた状態で連結具６２から吊り下げられた状態となる。
【００１８】
カップ状体６０内は、孔明き板６６によって仕切られ、この孔明き板６６を内筒１０が移動自在に貫通している。
孔明き板６６よりも下方の内筒１０上の部位にはストッパ６７が固定され、このストッパ６７と孔明き板６６との間には、ホイールを外したタイヤからなるクッション材６８が介挿されている。ストッパ６７によって、カップ状体６０は、内筒１０上に抜け止めして保持される。
【００１９】
カップ状体６０の下端側には、上に凸の断面半円状をなすグレーチング板（孔明き板）７０が固定されている。内筒１０の下端側は、このグレーチング板７０の中央に設けられた孔を貫通して上下動可能となっている。
カップ状体６０の孔明き板６６上、およびグレーチング板７０上には、適宜重量調節用の球体が収納されている。この球体はカップ状体６０内で転がり、粘土塊を砕き、スラリー化する作用もする。粘土塊中に微小ガスが含まれるときは、この微小ガスが放出され、後記するマイクロバルーンとして機能する。
カップ状体６０の外周上には、周方向に等間隔をおいて３つのチゼル７２が配設されている（図では１つのみ図示）。
チゼル７２は、内筒１０、カップ状体６０が落下したとき、水底面に突き刺さるように、下端が先鋭に形成されている。また、このチゼル７２にも、適宜引き上げ用のチエーンが連結され、台船３６上からこのチエーンを操作しうるようになっている。
【００２０】
台船３６上には、図４に示すように、水蒸気供給部（水蒸気発生装置：ボイラー）７３と、圧縮気体供給部たる圧縮空気供給部（コンプレッサー）７４が配設されている。
水蒸気供給部７３で発生した水蒸気および圧縮空気供給部７４で調整された圧縮空気は、フレキシブルな二重パイプ７５を通じて、カップ状体６０内上部に供給可能になっている。
【００２１】
二重パイプ７５は、図６に示すように、外筒７６と内筒７７とからなる。この二重パイプ７５の一端側から二重パイプ内に圧縮空気と水蒸気とが供給される。すなわち、外筒７６内には、接続口７８からパイプ７９を通じて圧縮空気が導入され、内筒７７内には接続口８０ａからパイプ８１ａを通じて水蒸気が導入される。
二重パイプ７５は、両管端を除いた中途部が、長尺で、かつフレキシブルな、ゴム等の気密な素材から形成された二重パイプをなし、貯水場所の湖底に十分到達可能な長さを有し、かつ屈曲可能になっている。
【００２２】
二重パイプ７５の他端側は、カップ状体６０の蓋６１に連結され、カップ状体６０内に圧縮空気、水蒸気が導入されるのである。
なお、外筒７６内には、断熱性に優れる圧縮空気が導入され、水蒸気は内筒７７内に導入されるので、水蒸気の冷却による凝結は極力防止される。
また、圧縮気体供給部７４からは、二重パイプ７５を通じて炭酸ガスをカップ状体６０内に供給するようにしてもよい。炭酸ガスは、高圧状態のときは水によく溶解し、低圧になると発泡する。これによりスラリーからなる流体膜中によく分散したマイクロバルーンが作り出され、流体の摩擦抵抗を低減させる。
【００２３】
次に浚渫作業について説明する。
浚渫開始前は、吸込口部１２が水底より約２ｍほどの高さとなるように引き上げておく。排出管１０は、動水勾配よりも下方となるように配設されているから、水（清水）は、水頭差５．０ｍ以上ならばＬ／Ｄ＝１０００でも排出管１０内を満杯になって流下し、秒速３．６ｍ以上の十分な流速、したがって、十分な慣性力を有するものとなる。
本実施の形態で、基本的には、排出管１０を上記のように動水勾配よりも下方となるように配設したことにより、水頭差により浚渫が可能となる。そして、以下に述べる操作を加えることにより、およびこの操作により生じる現象によって、粘土質の堆積物や、短径が管断面の７０％程度の石等の重量の大きなものであっても搬送、排出をより効果的に行えるものである。実際、普通の状態では沈降してしまって流れない、鉄（ρ＝７．４）でできたボルトなども搬送、搬出されたことが確認された。
【００２４】
上記のように、排出管１０内に十分な流速の水流が得られてから浚渫を開始する。
すなわち、まず、昇降装置３８を緩めることによって、吸込口部１２をカップ状体６０と共に自然落下させる。水底までの距離が２ｍの場合には、約３秒で吸込口部１２が水底に到達し、ウォッシュロードなどの非常に粒径の細かい、圧密された硬い粘土状の堆積物の場合には、吸込口部１２が０．１秒ほどで約３０ｃｍ程度水底の粘土層に食い込む。
【００２５】
これにより、吸込口部１２が急閉塞されることとなり、一方、排出管１０内の水は慣性力によってなおも流れようとするから、高濃度部分との境界部に低圧部分が生じ、膨張波となって下流側に伝播する。この粗密波の伝播速度は、パイプラインを弾性係数がＥ＝４ＧＰａの硬質ゴム製とすると、約２００ｍ／ｓｅｃとなる。また、低圧部分が生じることから、水中に溶解していた気体が分離し、ときには、圧力が降下してその水温の飽和蒸気圧になって水が蒸発する、水蒸気よりなる空泡、すなわち水柱分離が起こる。この場合キャビテーション（空泡の潰れ）も一部に起こる。すなわち空泡（キャビティ）の発生と潰れが同時に起こる。
水柱分離状態の下流部のところでは、水蒸気の発生とつぶれが同時に激しく起こっている。この水柱分離は、排出管１０内の高濃度部分の直下の下流で順次連続して起こるのであり、この水柱分離の下流への伝播速度はほぼ２０ｍ／ｓｅｃとなる。この水柱分離の伝播は、高圧部、低圧部が交互に発生して伝播することから、あたかもロープの端を持ってロープ端を上下に振ることによりロープにロープの横波が伝わるように、水平管部１４に、ロープと同様に、管の軸線方向と交差する方向への波打ち現象を発生させる。この波打ち現象による外部エネルギーは、排出管１０（パイプライン）内を、流体を下流に運ぶエネルギーの一つとなる。また、このように水平管部１４が大きく波打つことによって、管底に重力沈降しようとする固体を浮上させ、これにより固体を遠方まで搬送する効果も生じる。
【００２６】
この状態で、内筒（カップ状体６０内の鉛直管部１３の部位）１０をカップ状体６０に対して引き上げつつカップ状体６０内に圧縮空気または炭酸ガスを送り込み、次いで水蒸気を送り込む。これにより、また下流側が負圧になっていることと相俟って、吸込口部１２内に食い込んでいた、粘土が高い濃度で混合された部分（高濃度部分、すなわちプラグ）が内筒１０内を急上昇する。同時に、カップ状体６０内のスラリー（場合によっては清水）が内筒１０内に入ると共に、内筒１０内に圧縮空気、次いで水蒸気が入る。これにより、ガスプラグが形成され、密度差によるエアーリフト状態が作り出されるので、粘性の高い粘土プラグであっても、鉛直管部１３内を簡単に上昇するのである。
鉛直管部１３を過ぎて水平管部１４に流入すると、水蒸気が凝縮し、周辺の密度が大きくなるため、エアーや炭酸ガスは圧縮され、小粒となってスラリー中に分散する。このようにエアー等が小粒となって分散することによって、エアーロック状態の発生も防止できる。なお、エアーロック状態とは、水平管部１４に上に凸の屈曲部が生じた場合、この凸部にエアーが溜まると、流動圧がエアーの膨張、収縮作用に吸収され、流れなくなる状態をいう。
上記エアーや炭酸ガスの小粒が、次に膨張波が発生すると、水の表面張力を破壊する源となり、簡単に水柱分離状態を作り出すのである。
【００２７】
次いでカップ状体６０が引き上げられる（内筒１０が所要高さまで引き上げられるとストッパ６７によってカップ状体６０も引き上げられる）。カップ状体６０内が水蒸気と圧縮空気で満たされる状態となっているので、浮力が働き、カップ状体６０は容易に引き上げられ、初期の状態に戻る。
カップ状体６０を引き上げた直後に水蒸気と圧縮空気の吹き込みを中断すると、水蒸気が凝縮して０．５気圧以下の低圧に急激になることから、１．５気圧以上の吸込口周囲の高圧の清水が急激に流れ込む。すなわち、弁の急開状態となって、これにより、排出管１０内に圧力波が発生する。これが排出管１０内を伝播する。
【００２８】
圧力波が発生することによって、ガスプラグは急激に圧縮されることとなり、また、ガスプラグ中の水蒸気が凝結して水に取り込まれることも相俟って、流体間に衝突が起こり、ガスプラグはさらに圧縮され、急激に圧力が高くなる。このときには、体積の弾性変化を伴う水撃現象が生じると同時に、プラグとガスプラグおよび液体との間で、相対速度差が秒速１００ｍにもなる物体間の非弾性衝突状態が現出され、排出管１０中に、固・液・気の三相よりなる、加速度の急変化を有する連成振動子状の流れが生じ、プラグの輸送が効率的になされる。
特に、慣性流体中の物体に密度差があり、衝突と表現されるような加速度の急変（急発進、急停止）は物体間に圧力差を発生させ、鉄塊のようなものの輸送まで可能にするのである。
なお、水撃現象とはウォーターハンマー現象のことを言い、水であっても圧縮され、体積が小となることを無視できないような衝突現象を言う。
【００２９】
上記の吸込口部１２の落下、上昇サイクルが繰り返されることによって、排出管１０内を流れる流体は、粘土が高い濃度で混合しているプラグ部（高濃度部）と、低い濃度で混合している部分（上記清水部分およびガスプラグ部分。水蒸気ガスプラグ部分は下流側にいくと外部の水により冷やされて消失し、上流部を真空吸引する。）とが交互に発生するプラグ流となる。
【００３０】
また、上記のように、高濃度部と高濃度部との間の低濃度部に膨張波（真空波：膨張する波）と圧力波（粗密波）が交互に生じる状況となって、流体は排出管１０内で激しく振動する振動流状態で流れ、高い濃度の粘土が、排出管１０の管壁にほとんど接触することなく、すなわち、管路抵抗が低い状態で流れるので、排出管１０が長くても良好に粘土（土砂）の運搬がなされる。Ｌ（長さ）／Ｄ（直径）が、１０００〜１５００くらいの長い管路であっても、平均流速１．３ｍ／ｓｅｃで十分良好に高濃度の土砂の排出ができることが確認されたことからもわかる。因みに、水頭差が５．０ｍで、Ｃ_v＝７ｖｏｌ％、ρ＝１．１の粘土スラリーをＬ／Ｄ＝１００で流したとき、スラリーの管内壁付着とスラリー自身の粘性により管閉塞が起こり、流速が０となった。
なお、流体が排出管１０内で激しく振動しつつ流れる状況は、排出管１０の一部を透明にして観察した結果、各所の水柱分離長さが５０ｃｍにも達し、その負圧により数秒間の逆流現象が生じ、次に上流部からの圧力回復により水柱分離が消失し、長さが０ｃｍになるとき、秒速１００ｍにも及ぶ急加速された流体が下流部に衝突する。このように管内を激しく振動しながら流下することが確認された。
図９に管路損失と真体積濃度（固相率）との相関図を示す。λはシステム全体の抵抗係数を示す。なお、計算式上、流動に関する係数が数十個になり、解が発散するため、実用上問題のないλにまとめた。図９は、排出管に、直径１５ｃｍ、長さ１５０ｍのものを用いて、水頭差５．０ｍ、動水勾配ｉ＝０．０３３で、種々の固相率の流体の搬送（浚渫）を行った結果を示すものである。
流体がニュートン流体の場合には、流速３．６ｍ／ｓｅｃで支障なく流れる。
ビンガム流体の場合には、本実施の形態のような操作（鉛直管部１３の昇降操作等）を行わない（図で脈動無し条件としている）と、まもなく管閉塞が生じ、流れなくなる。
本実施の形態の上記操作を行うことによって、抵抗係数はそれ程増大せず、ビンガム流体はもとより、固相率が３０％程度の塑性流体であっても、排出、搬送することができた。
【００３１】
上記のように、排出管１０内に間隔をおいて発生しているプラグ部間の低濃度部に、膨張波（液状あるいは気体状）、圧力波（液状）が交互に発生して、固・液・気（水柱分離を含む）の三相状態で流れることは、あたかも、長い下り坂を重力で降下中の、連結器（低濃度部）で連結された多数車輌の貨車（高濃度部）が機関車により坂の途中で急発進、急停車されるときの状況と似ており、多数の連結器の延び、縮みの働きによって、少ないエネルギーで、発進あるいは停車できるのと同様に、少ないエネルギー、すなわち坂の勾配による重力の水平分力と小さな慣性力のシナジー効果（相乗効果）で、高濃度、高粘性流体が排出管１０内を、沈降、堆積することなく平均１．３ｍ／ｓｅｃの低速で排出口へ流れるのである。
管の摩耗量は、流速の２乗に比例する実測値から判断しても、システム全体の耐久性が数倍向上していることは明らかである。
【００３２】
また、上記のように、水蒸気は凝結して水中に取り込まれる。一方吹き込まれた圧縮空気は、一部は水中に溶解するが、大部分は排出管１０の管壁と固体との間の流体膜中に小粒子（マイクロバルーン）となって分散し、流体と共に排出される。このように空気が排出管１０の管壁に付着する流体膜中に分散することによって、ますます流体の管路抵抗を減じ、流体が良好に排出される一因となる。圧縮気体として炭酸ガスを用いると、高圧のときは水に溶解し、低圧のときは発泡するので、上記の連成振動子状態の流れをより作りやすくなる。
このようにして、固相率が３０％程度の高濃度ウォッシュロードが圧密された硬くて、かつ非常に粘性の高い堆積物であっても良好に排出できる。
【００３３】
なお、圧縮気体供給部７４、水蒸気供給部７３から、圧縮気体および水蒸気を供給あるいは遮断するのは図示しない電磁バルブによって行い、この電磁バルブの開閉のタイミングは、上記吸込口部１２の昇降のタイミング、すなわち、クランク機構等によって構成される前記昇降装置３８の駆動のタイミングに合わせて行われるよう制御される。
【００３４】
また図示しないが、排出管１０の内面にスパイラル状の突起を設け、リブレットを形成することによって（溝部と突起が交互に螺旋状に連続する）、ライフル銃の玉が回転しながら発射されてより抵抗が少なくなるのと同様にして、パイプライン内のプラグおよび流体が回転することによってプラグの抵抗がさらに減少し、堆積物がよりスムーズに排出される。また、膨張波発生によって、管断面が増減するが、この管断面増減が上記の回転を一層高める（スピン効果）ことになる（管断面減少により、プラグの回転速度が増し、流体膜間の剪断速度差が大きくなる）。
【００３５】
ところで、上記のように、流体中にキャビテーションや水撃現象が生じ、排出管１０に作用する破壊力が大きくなる。これによる排出管１０の損傷を防止し、システムの耐久性を高めるための機構の一例を図７および図８により説明する。
まず、基本的には、排出管１０に作用する破壊力を排出管１０自らによって吸収できるように、排出管１０には、有機物質で弾性係数Ｅが、Ｅ＝４ＧＰａ程度のゴム等の弾力性の大きい材料のものを用いるとよい。
なお、管径が１００ｃｍ以上となる大径の排出管１０を使用する場合には、鉄板で補強した断面台形状のゴム板を鉄板側を外側にしてスパイラル状に巻いて接合したフレキシブルなパイプ構造に形成したものを用いるとよい（図１０参照）。
【００３６】
図７で、８０はフロートであり、排出管１０の鉛直管部１３と水平管部１４との間の屈曲部に位置して配置され、排出管１０に浮力を付与している。フロート８０は、パイプ８１により、台船３６上の前記圧縮空気供給部７４に接続され、圧縮空気の給排がなされる。
８２は圧力吸収部であり、排出管１０内と連通し、排出管１０内の増圧、減圧を吸収し、排出管１０に加わる上記破壊力を軽減するようになっている。圧力吸収部８２は、排出管１０の水平管部１４の適宜箇所に設けられるものであり、図示の例では３基連結されている。
【００３７】
図８は圧力吸収部８２の具体例を示す。
この例では、圧力吸収部８２は車のタイヤに類似した構造を用いている。
８４はアルミニウム、鉄等の金属からなる保持リングであり、この保持リング８４内を排出管１０が挿通している。この保持リング８４は適宜手段により排出管１０外周上に固定されている。また保持リング８４は、孔８５を通じて、排出管１０内と液密、気密に連通している。
【００３８】
８６は外チューブであり、車のタイヤと同じように、保持リング８４外周に嵌め込まれて、保持リング８４と共に、密閉したチューブ空間を構成する。８７は内チューブであり、外チューブ８６内に配設されている。
外チューブ８６内には、保持リング８６に設けたバルブ８８、連結ホース８９を通じて圧縮空気および水蒸気が供給される。３基の圧力吸収部８２の外チューブ８６間は連結ホース８９によって連通され、最端部の圧力吸収部８２の外チューブ８６内には、図６に示すのと同じ構造の二重パイプ７５を通じて圧縮空気および水蒸気が供給される。二重パイプ７５は、台船９０（図７）上に設けられた圧縮空気供給部７４および水蒸気供給部７３に接続パイプを介して接続される。
【００３９】
内チューブ８７には、保持リング８４に設けたバルブ９１、内チューブ８７に設けたバルブ９２、これらを連結するホース、さらにはホース９３を介して圧縮空気が供給される。ホース９３は、台船９０上に設けた圧縮空気供給部９５に接続される。また３基の圧力吸収部８２の内チューブ８７間は、連結ホース９６によって連通されている。
【００４０】
圧力吸収部８２は上記のように構成されている。
内チューブ８７内の圧力は、外チューブ８６内空間の圧力と平衡状態となり、外チューブ８７を潰れないように保持する役目をするが、場合によっては内チューブ８７は設けなくともよい。
排出管１０内に膨張波が発生し、圧力が低下した場合には、外チューブ８６内から孔８５を通じて圧縮空気および水蒸気が排出管１０内に流入し、これにより排出管１０の急な変形が防止される。また、排出管１０内を比較的大きな石９７等が流れる場合には、排出管１０内に供給される水蒸気が潰れて圧力低下することにより、石９７の流れ方向側に低圧の水柱分離部９８が形成されやすくなり、前記固・液・気の三相よりなる連成振動子状の流れが生じるのを助長し、プラグや石等の輸送がさらに効率的になされる。
【００４１】
排出管１０内に圧力波が発生し、圧力が上昇した場合には、外チューブ８６内に水が流入し、排出管１０内の圧力の突発的な上昇を吸収することから排出管１０の急激な変形を防止できる。
このように、圧力吸収部８２を設けることにより、流体中にキャビテーションや水撃現象が生じても、圧力吸収部８２により圧力変化を吸収でき、固体輸送に必要な脈動状態を保つことができ、かつ排出管１０の損傷を極力防止できる。
【００４２】
上記圧力吸収部８２は、フロートの役目もするので、水平管部１４の適所に適宜間隔をおいて配設することで、水平管部１４を動水勾配以下の所に容易に配置できるようになる。
なお、圧力吸収部８２は上記構成には限定されない。例えば、単にフロート状に形成し、排出管１０内と孔もしくは適宜パイプを介して連通して、排出管１０内の圧力変化を吸収するようにしてもよい。
【００４３】
ダム湖等における浚渫の場合、大洪水時には、ダム湖内にも３ｍ／ｓｅｃ以上の急激な水流が発生し、排出管１０にも極めて大きな力が作用し、排出管１０が大きなダメージを受けるおそれがある。
このような大洪水の場合には、排出管１０全体を湖底に沈めるようにするとよい。
そのためには、台船３６からの吊りのワイヤーなどを緩め、また二重パイプ７５やパイプ８１、９３などを緩め、さらには、フロート８０や圧力吸収部８２内の気体を排出して、排出管１０を湖底に沈めるようにする。湖底は水流の流速が小さくなるため、排出管１０へのダメージを小さくすることができる。
【００４４】
上記実施の形態では、ダム湖に堆積した堆積物の浚渫を例に説明したが、これに限られるものではない。池や湖沼等の貯水場所や海における浚渫にも吸入側と排出側に水位差（圧力差）を付けることにより当然利用できる。
あるいは、タンカー内の積み荷である例えば石炭や鉄鉱石をタンカー内から排出する場合にも、タンカー内に水を注入した後、上記実施の形態と同様の構造でもって水流と共に石炭や鉄鉱石を外部に排出するなど、貯水場所内に堆積した堆積物を外部に搬送する、堆積物の搬送機構にも応用しうるものである。
また、ρ＝７．４の鉄塊を浚渫した事実より、パイプライン内の急な圧力差による急な加速度の変化を与える上記の機構は、深海の有用物質の採取やメタンハイドレードの採取機構としても応用しうる。
また、固、液、気の連成振動子状流れが生じることから、原油の長距離輸送にも好適である。
特に、パイプラインの吸込口での弁の急閉、急開によるパイプライン内の急な圧力の変化は心臓の脈動にも通じ、吸込口での膨張波の発生機構は、人工心臓の血液中の赤血球や血小板の輸送に応用でき、その際、赤血球の変形能や血小板の凝集能の活性化（刺激）にも寄与する。
【００４５】
以上本発明につき好適な実施例を挙げて種々説明したが、本発明はこの実施例に限定されるものではなく、発明の精神を逸脱しない範囲内で多くの改変を施し得るのはもちろんである。
【００４６】
【発明の効果】
本発明によれば、上述したように、搬送管内に間隔をおいて発生しているプラグ部間の低濃度部に、膨張波（液状あるいは気体状に発生する低圧部：真空波）、圧力波（液状）が交互に発生して、固・液・気（水柱分離を含む）の三相よりなる連成振動子状の流れが生じ、あたかも、連結器（低濃度部）で連結された貨車（高濃度部）が機関車により急発進、急停車されるときの状況と似ており、バネでできた連結器の延び、縮みの働きによって、少ないエネルギーで、発進あるいは停車できるのと同様に、少ないエネルギー、すなわち小さな慣性力であっても、重力（水頭差；圧力差）との相乗効果で、高濃度、高粘土の流体が搬送管内を長距離流れるという効果を奏する。
【図面の簡単な説明】
【図１】ダム湖での浚渫機構の例を示す説明図、
【図２】美和ダムの構造を示す説明図、
【図３】搬送管（排出管）の堰堤孔部での固定機構を示す説明図、
【図４】台船の説明図、
【図５】吸込口部分におけるカップ状体の構造を示す説明図、
【図６】二重パイプの構造を示す説明図、
【図７】圧力吸収部の説明図、
【図８】圧力吸収部のさらに詳細を示す説明図である。
【図９】管路損失と固相率との相関図である。
【図１０】排出管の一例を示す断面図である。
【符号の説明】
１０排出管
１２吸込口部
１３鉛直管部
１４水平管部
１８吐出口
２０貯水場所
２２堆積物
２４堰堤孔部
３０放出部
３６台船
３７クレーン
３８昇降装置
６０カップ状体
７２チゼル
７３水蒸気供給部
７４圧縮空気供給部
７５二重パイプ
８２圧力吸収部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a deposit transport mechanism and a deposit transport method.
[0002]
[Prior art]
There is a mechanism shown in Japanese Patent No. 3277489 as a saddle mechanism.
This dredge mechanism
The discharge pipe is placed through a dam hole provided at a position lower than the water level of the water storage place, and the discharge pipe is placed at a position lower than the water level of the water storage place by a trolley floated in the water storage place. Suspended to be located,
By using the lifting device provided on the base boat, the discharge pipe is moved up and down so that the suction port comes in contact with and separates from the water bottom of the storage place in a required cycle to obtain a pulsating flow that is a pulsating suction flow. At the same time, a plug flow in which a flow in which the sediment is mixed at a high concentration and a flow in which the sediment is mixed at a low concentration is alternately generated is obtained.
According to this dredging mechanism, the deposit can be efficiently discharged as a solid-liquid two-phase flow without bringing the deposit into contact with the tube wall of the discharge tube so as to be substantially resistant.
[0003]
[Patent Document 1]
Japanese Patent No. 3277489 (Claims)
[0004]
[Problems to be solved by the invention]
An object of the present invention is to provide a deposit transport mechanism and a deposit transport method that can be applied to the conventional dredging mechanism and can transport the deposit more efficiently.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, the present invention comprises the following arrangement.
That is, the deposit transport mechanism according to the present invention includes a suction port portion that is opened to face the bottom of the water on which deposits are accumulated in a water storage location, a vertical pipe portion that extends in the vertical direction from the suction port portion, and the vertical pipe A horizontal pipe portion extending substantially horizontally in the lateral direction from the top of the section and opened to a discharge portion located lower than the water storage location, the horizontal pipe portion being provided at a position lower than the water level of the water storage location. And is supported in a position below the hydrodynamic gradient line in the water in the water storage place. A transfer pipe that is moved up and down so that the mouth part contacts and separates from the bottom surface of the water storage area in a required cycle, and a suction port part of the transfer pipe, and the suction port part is movable in the vertical direction. A cup-like body having an open shape and entering downward, Tsu and steam supply unit for supplying steam to the looped body is characterized by comprising a compressed gas supply unit for supplying compressed gas to said cup-shaped body.
Then, the suction port side is lowered together with the cup-like body, the suction port bites into the water bottom surface, and the suction port is suddenly closed, so that the inertia force of the fluid in the transfer pipe causes the suction port side. Expansion pressure is generated due to the pressure drop, and water column separation occurs in the low-concentration part in the transport pipe from the suction port side, with water vapor generated in the low-pressure part of the solid surface, and then sucks into the cup-shaped body. The mouth portion is raised, the high concentration portion that has entered the suction port is sucked as a plug, and a small amount of compressed gas is supplied from the compressed gas supply portion to the cup-shaped body, and the compressed water supply portion is more than the compressed gas. By supplying a large amount of water vapor into the cup-shaped body, a high-concentration sediment at the bottom of the water, a water in the cup-shaped body, compressed gas and water vapor flow into the suction port, and the plug is made of a high-concentration sediment. And pressure A gas plug made of gas and water vapor is formed to raise the vertical pipe part, then the cup-like body is raised, and supply of the compressed gas and water vapor is stopped, so that water vapor in the gas plug part is condensed. The volume of the gas plug is reduced, and the suction port is opened rapidly. As a result, fresh water flows into the suction port, the pressure on the suction port increases, pressure waves are generated, and the water column separation unit is condensed. By repeating the cycle, a coupled oscillator-like flow composed of solid, liquid, and gas is created in the transport pipe, and the deposit is carried out to the discharge section.
In the case of a fluid having a high adhesive force (Bingham fluid), a thick fluid film adheres to the tube wall or solid surface and is difficult to flow. However, according to the present invention, the structure for generating the adhesive force of the fluid film is High local pressure due to cavitation of emulsion flow (emulsion-like flow) that is reduced by shear force due to violent vibration caused by cavitation of separation part (thixotropic effect), and further, fine gas flow (microballoon) generated in fluid film is dispersed This allows fluid to intervene between solids without contacting the solids, always keeps the fluid film in a fluid lubrication state of dynamic friction coefficient, and transports even high-density, high-viscosity volumes with high efficiency. Make it possible.
[0006]
Moreover, in this invention, the said compressed gas supply part supplies compressed air or a carbon dioxide gas, It is characterized by the above-mentioned.
There is a trolley floated at the water storage place, and a suspension device for supporting the transport pipe and the transport pipe are connected to and separated from the bottom surface in a required cycle with respect to the bottom surface of the water. The elevating device that moves up and down as described above, the water vapor supply unit, and the compressed gas supply unit are arranged.
In addition, it is preferable to provide a pressure absorbing portion that is provided in communication with the inside of the transfer pipe and absorbs a drastic increase and decrease in pressure caused by a water hammer in the transfer pipe.
[0007]
Further, in the deposit transport method according to the present invention, the suction port portion that is opened to face the bottom of the water on which deposits are accumulated in the water storage location, the vertical pipe portion that extends in the vertical direction from the suction port portion, and the vertical pipe portion A horizontal pipe portion extending substantially horizontally in the lateral direction from the top and opened toward the discharge portion located lower than the water storage location, the horizontal pipe portion being provided at a position lower than the water level of the water storage location. It is arranged so as to penetrate the hole liquid-tightly, and is supported in a position below the hydrodynamic gradient line in the water in the water storage place. Is provided at the transport pipe that is moved up and down so as to make contact with and away from the bottom surface of the water storage site in a required cycle, and the suction port section of the transport pipe is movably entered in the vertical direction. A cup-like body having a shape opened downward, and the cup Using a deposit transport mechanism comprising a water vapor supply unit for supplying water vapor to the body and a compressed gas supply unit for supplying compressed gas to the cup body, the suction port side is lowered together with the cup body. , By causing the suction port portion to bite into the bottom of the water and closing the suction port portion suddenly, the pressure on the suction port portion side is reduced by the inertial force of the fluid in the transport tube to generate an expansion wave, Water column separation is sequentially generated in the low concentration portion from the suction port side, then the suction port portion is raised with respect to the cup-shaped body, the high concentration portion entering the suction port is sucked as a plug, and the compressed gas supply A small amount of compressed gas is supplied to the cup-shaped body from the section, and a larger amount of water vapor than the compressed gas is supplied to the cup-shaped body from the water vapor supply section. , Compressed gas and water vapor are allowed to flow into the suction port to form a plug and gas plug made of high-concentration deposits to raise the vertical pipe, and then to raise the cup-like body, the compressed gas and By stopping the supply of water vapor, the water vapor in the gas plug part is condensed, the volume of the gas plug is reduced, the suction port part is opened rapidly, and thereby fresh water flows into the suction part, and the suction part side By repeating the cycle of generating a pressure wave and condensing the water column separation unit by increasing the pressure of the water, a coupled oscillatory flow consisting of solid, liquid, and gas is created in the transport pipe, and the deposit is discharged into the discharge unit. It is characterized by being carried out to
The compressed gas supply unit supplies compressed air or carbon dioxide into the cup-shaped body.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a cross-sectional view showing a dredging mechanism as an example of a deposit transport mechanism.
This dredging mechanism is applied to a huge dam lake.
Reference numeral 10 denotes a discharge pipe which is a long transport pipe, and a suction port portion 12 which is opened to face the bottom of the water storage place 20 (lake bottom 29) such as a dam lake where sediment 22 such as earth and sand is deposited, and its suction port portion A vertical pipe portion 13 that extends vertically upward from 12 and a discharge port that extends substantially horizontally in the lateral direction from the top of the vertical pipe portion 13 and opens to a discharge portion (discharge water channel) 30 such as a bypass tunnel that is lower than the water storage location 20. And a horizontal pipe portion 14 having 18.
[0009]
Figure 2 shows the mechanism of the bypass tunnel at Miwa Dam in Nagano Prefecture.
On the upstream side of the dam bank 31, a branch bank 33 and a sand storage dam 34 are provided. The sand storage dam 34 and the branch dam 33 block rough earth and sand, reduce the amount of solid flowing into the downstream dam lake, and facilitate the removal of the deposited solid after the flood. These coarse earth and sand are mechanically carried out as before and are effectively used for concrete materials.
At the time of flood, open the gate (not shown) of the bypass waterway (not shown) provided near the branch 33, and let the fine earth and sand (diameter about 0.1mm) flow into the bypass tunnel 30 through the bypass waterway with the flood. Prevent fine sediment from accumulating in the dam lake. Therefore, sediments with extremely small particle diameters called mainly wash roads are deposited on the dam lake.
[0010]
In the present embodiment, the trapped sediment is discharged using the auxiliary tunnel (auxiliary water channel) 32 leading to the bypass tunnel 30.
The discharge end side of the discharge pipe 10 is led into the auxiliary tunnel 32 through the dam hole portion 24.
[0011]
The dam hole portion 24 is provided to open to the dam 25 of the water storage place 20 so that the discharge pipe 10 passes through a position lower than the water level 21 of the water storage place 20.
A horizontal pipe portion (set so that the side of the dam hole portion 24 is slightly lowered) 14 that is bent at a substantially right angle at the upper part of the vertical pipe portion 13 of the discharge pipe 10 and that extends in the horizontal direction, And it arrange | positions so that it may pass through the position below a dynamic gradient line.
Thereby, it will flow down in the state with which the water flow was satisfy | filled by the water head difference energy in the discharge pipe 10 (in the case of fresh water).
“Shimizu” refers to what is regarded as a Newtonian fluid when ρ (average density) ≦ 1.044 (in the case of Miwa dam lake bottom clay wall in Nagano Prefecture).
The case of 1.5>ρ> 1.044 is referred to as a high-concentration fluid, and shows Bingham fluid characteristics. A highly viscous material is called a Bingham fluid. Further, when the solid phase ratio is 30% or more, ρ ≧ 1.5, and the case of clay is called a plastic fluid, where the solid phase is concentrated (plug) is intermittently present. This is called plug flow. In the case of a plug flow, a plug-like clay film (fluid film) may be formed on the surface of the plug, which is called a capsule fluid.
[0012]
The dam hole portion 24 needs to have a watertight structure, which will be described with reference to FIG.
A plurality of roller-shaped receiving members 42 are disposed in the dam hole 24 and receive the discharge pipe 10 so as to be able to move smoothly in the axial direction.
Reference numeral 50 denotes a seal member, which is formed of, for example, a rubber material in an air bag shape, and air is injected therein. The seal member 50 is disposed between the dam hole portion 24 and the discharge pipe 10 (up and down of the discharge pipe 10), and seals between the dam hole portion 24 and the discharge pipe 10 in a liquid-tight manner.
[0013]
By tightening the air in the seal member 50, the tightening of the discharge pipe 10 is released, and the discharge pipe 10 can move in the axial direction.
The receiving member 42 is disposed on both sides of the seal member 50 on the dam housing 44.
52 is a sluice board. The sluice plate 52 is movably disposed in a groove 53 (FIG. 1) provided in the vertical direction on the dam portion 25 (FIG. 1), and is driven up and down by power to open and close the sluice (the dam hole portion 24). It has become.
The sluice plate 52 is lowered and the discharge pipe 10 is sandwiched through the seal member 50 to seal the dam hole portion 24 in a liquid-tight manner.
[0014]
Next, 36 is a trolley (FIG. 1), a crane 37 is disposed, and the crane 37 causes the discharge pipe 10 to be vertical to the vertical pipe section 13 and the horizontal pipe section 14 to be from a hydrodynamic gradient. Is also suspended so that it is at the bottom. A bent part between the vertical pipe part 13 and the horizontal pipe part 14 is also located in the water. The hanging position of the discharge pipe 10 can be freely changed by the crane 37.
Further, as shown in FIG. 4, an elevating device 38 that moves the vertical pipe portion 13, and hence the suction port portion 12, up and down is provided on the carriage 36. The elevating device lifts the vertical pipe portion 13 by about 2 m from the discharge pipe 10 which is composed of, for example, a crank device and is suspended by the crane 37 so as to move the chain 62 connected to the vertical pipe portion 13 up and down. After that, the vertical pipe portion 13 is configured to fall naturally.
[0015]
The lifting device is not limited to the crank device, and may be any device that can move the vertical pipe portion 13 up and down. A motor, a cylinder device, or the like can be employed as the drive unit (not shown) of the lifting device.
Further, even if it is not the crane 37, it may be anything that can suspend the discharge pipe 10 as described above.
In addition, a support stand (not shown) may be erected in the dam lake as the case may be instead of the base boat 36, and the discharge pipe 10 may be supported by this support stand or a lifting device may be provided on the support stand. Good.
The support for supporting the discharge pipe 10 may be configured as a float (not shown) that floats in water. Air is supplied to and discharged from the float so that the height of the discharge pipe 10 can be adjusted. In this case, a watertight electric motor (not shown) is attached to the float, and the vertical pipe portion 13 is moved up and down by this electric motor. Electricity is supplied to the electric motor from wiring (not shown) provided along an air supply pipe (not shown) to the float in order to avoid leakage.
[0016]
Next, FIG. 5 is explanatory drawing which shows an example of the suction inlet 12 part in detail.
As shown in FIG. 5, the suction inlet 12 has a double cylinder structure of an inner cylinder (discharge pipe 10) and a cup-shaped body 60.
The cup-shaped body 60 has a cup shape with its upper end side closed by a lid 61, and the lower end portion of the discharge pipe 10 (hereinafter sometimes referred to as an inner cylinder) is capable of moving the lid 61 up and down, liquid-tight and air-tight. It penetrates and enters the cup-shaped body 60. A connecting tool 62 is fixed to a portion of the discharge pipe 10 slightly above the cup state 60. A chain 63 is connected to the connecting tool 62, and the chain 63 is connected to the lifting device. Can be moved up and down.
[0017]
The cup-shaped body 60 is in a liquid-tight state and is movable up and down relatively with respect to the inner cylinder 10. The lid 61 of the cup-shaped body 60 and the coupling tool 62 are coupled by a coil spring 65, and the cup-shaped body 60 moves relative to the inner cylinder 10 within a range where the coil spring 65 expands and contracts. Therefore, when the inner cylinder 10 is pulled upward from the bottom of the water, the cup-shaped body 60 is suspended from the connector 62 with the coil spring 65 extended.
[0018]
The cup-shaped body 60 is partitioned by a perforated plate 66, and the inner cylinder 10 penetrates the perforated plate 66 so as to be movable.
A stopper 67 is fixed to a portion on the inner cylinder 10 below the perforated plate 66, and a cushion material 68 made of a tire from which a wheel is removed is inserted between the stopper 67 and the perforated plate 66. ing. The cup-like body 60 is held on the inner cylinder 10 by the stopper 67 so as not to come off.
[0019]
On the lower end side of the cup-shaped body 60, a grating plate (perforated plate) 70 having a semicircular shape with an upward convex cross section is fixed. The lower end side of the inner cylinder 10 can move up and down through a hole provided in the center of the grating plate 70.
On the perforated plate 66 and the grating plate 70 of the cup-shaped body 60, spheres for weight adjustment are appropriately stored. This sphere rolls in the cup-shaped body 60, and also acts to crush the clay mass and make it into a slurry. When a minute gas is contained in the clay mass, this minute gas is released and functions as a microballoon described later.
On the outer periphery of the cup-shaped body 60, three chisels 72 are arranged at equal intervals in the circumferential direction (only one is shown in the figure).
The chisel 72 is formed with a sharp lower end so that the inner cylinder 10 and the cup-shaped body 60 are pierced into the bottom surface of the water. The chisel 72 is also appropriately connected with a lifting chain so that the chain can be operated from the carriage 36.
[0020]
As shown in FIG. 4, a water vapor supply unit (water vapor generating device: boiler) 73 and a compressed air supply unit (compressor) 74 serving as a compressed gas supply unit are disposed on the carriage 36.
The steam generated in the steam supply unit 73 and the compressed air adjusted by the compressed air supply unit 74 can be supplied to the upper part of the cup-shaped body 60 through the flexible double pipe 75.
[0021]
As shown in FIG. 6, the double pipe 75 includes an outer cylinder 76 and an inner cylinder 77. Compressed air and water vapor are supplied into the double pipe from one end side of the double pipe 75. That is, compressed air is introduced from the connection port 78 through the pipe 79 into the outer cylinder 76, and water vapor is introduced into the inner cylinder 77 from the connection port 80a through the pipe 81a.
The double pipe 75 is a double pipe formed of an airtight material such as rubber, which is long and flexible, except for the ends of both pipes, and is long enough to reach the bottom of the lake in the reservoir. And bendable.
[0022]
The other end of the double pipe 75 is connected to the lid 61 of the cup-shaped body 60, and compressed air and water vapor are introduced into the cup-shaped body 60.
In addition, since compressed air excellent in heat insulation is introduced into the outer cylinder 76 and water vapor is introduced into the inner cylinder 77, condensation due to cooling of the water vapor is prevented as much as possible.
Further, carbon dioxide gas may be supplied from the compressed gas supply unit 74 into the cup-shaped body 60 through the double pipe 75. Carbon dioxide gas dissolves well in water at high pressure, and foams at low pressure. This creates microballoons that are well dispersed in the fluid film of slurry, reducing the frictional resistance of the fluid.
[0023]
Next, the dredging work will be described.
Before starting dredging, the suction port 12 is pulled up so that it is about 2 m above the bottom of the water. Since the discharge pipe 10 is disposed below the dynamic water gradient, the water (fresh water) fills the discharge pipe 10 even at L / D = 1000 if the head difference is 5.0 m or more. And a sufficient flow velocity of 3.6 m / s or higher, and therefore a sufficient inertial force.
In the present embodiment, basically, the discharge pipe 10 is disposed so as to be lower than the hydrodynamic gradient as described above, so that dredging is possible due to a water head difference. And by adding the operation described below and the phenomenon caused by this operation, even if it is a heavy thing such as clay deposits or stones whose minor axis is about 70% of the cross section of the pipe, Can be performed more effectively. In fact, it was confirmed that bolts made of iron (ρ = 7.4) that would sink and flow under normal conditions were also transported and unloaded.
[0024]
As described above, dredging is started after a water flow having a sufficient flow velocity is obtained in the discharge pipe 10.
That is, first, the suction device 12 is naturally dropped together with the cup-like body 60 by loosening the lifting device 38. When the distance to the bottom of the water is 2 m, the suction port 12 reaches the bottom in about 3 seconds, and in the case of a hard clay compact sediment with a very fine particle size such as a wash load, The suction port 12 bites into the clay layer of about 30 cm in about 0.1 seconds.
[0025]
As a result, the suction port 12 is suddenly closed, while the water in the discharge pipe 10 still tends to flow due to the inertial force, so that a low-pressure portion is generated at the boundary with the high-concentration portion, and the expansion wave And propagates downstream. The propagation speed of this dense wave is about 200 m / sec when the pipeline is made of hard rubber having an elastic modulus of E = 4 GPa. In addition, since a low-pressure part is generated, the gas dissolved in the water is separated, and sometimes the pressure drops to the saturated vapor pressure of the water temperature to evaporate the water. Happens. In this case, cavitation (collapse of air bubbles) also occurs partly. That is, air bubbles (cavities) are generated and crushed simultaneously.
In the downstream part of the water column separation state, the generation and crushing of water vapor occur at the same time. This water column separation occurs successively and immediately downstream immediately below the high concentration portion in the discharge pipe 10, and the propagation speed to the downstream of this water column separation is approximately 20 m / sec. The propagation of this water column separation occurs alternately in the high-pressure part and low-pressure part. Similar to the rope, the portion 14 is caused to undulate in the direction intersecting the axial direction of the tube. The external energy due to this undulation phenomenon becomes one of the energy for transporting the fluid downstream in the discharge pipe 10 (pipeline). Further, since the horizontal pipe portion 14 undulates in this way, the solid to be gravity settled on the bottom of the pipe is floated, thereby producing an effect of transporting the solid far away.
[0026]
In this state, compressed air or carbon dioxide gas is fed into the cup-shaped body 60 while pulling up the inner cylinder (part of the vertical pipe portion 13 in the cup-shaped body 60) 10 with respect to the cup-shaped body 60, and then water vapor is fed. Thereby, in combination with the negative pressure on the downstream side, the portion mixed with high concentration of clay (high concentration portion, that is, plug) that bites into the suction port portion 12 is the inner cylinder 10. Soars inside. At the same time, slurry (in some cases, fresh water) in the cup-shaped body 60 enters the inner cylinder 10, and compressed air and then water vapor enter the inner cylinder 10. As a result, a gas plug is formed, and an air lift state due to a density difference is created. Therefore, even in a clay plug having a high viscosity, the inside of the vertical pipe portion 13 is easily raised.
When the water passes through the vertical pipe part 13 and flows into the horizontal pipe part 14, the water vapor is condensed and the density of the surrounding area is increased. Therefore, the air and carbon dioxide are compressed and dispersed in the slurry as small particles. In this way, air and the like are dispersed as small particles, so that the occurrence of an air lock state can also be prevented. Note that the air lock state is a state in which when a convex bent portion is formed on the horizontal pipe portion 14 and the air accumulates in the convex portion, the fluid pressure is absorbed by the expansion and contraction action of the air and does not flow. Say.
When the expansion wave is generated next by the air or carbon dioxide gas particles, the surface tension of the water is destroyed, and a water column separation state is easily created.
[0027]
Next, the cup-shaped body 60 is pulled up (when the inner cylinder 10 is pulled up to the required height, the cup-shaped body 60 is also pulled up by the stopper 67). Since the cup-shaped body 60 is filled with water vapor and compressed air, buoyancy works, and the cup-shaped body 60 is easily pulled up and returns to the initial state.
If the blowing of water vapor and compressed air is interrupted immediately after pulling up the cup-shaped body 60, the water vapor condenses and suddenly becomes a low pressure of 0.5 atm or less, so the high pressure around the suction port of 1.5 atm or more Shimizu flows in rapidly. That is, the valve is opened rapidly, thereby generating a pressure wave in the discharge pipe 10. This propagates in the discharge pipe 10.
[0028]
When the pressure wave is generated, the gas plug is rapidly compressed. In addition, the water vapor in the gas plug condenses and is taken into the water, and a collision occurs between the fluids. Is further compressed and the pressure suddenly increases. At this time, a water hammer phenomenon accompanied by an elastic change in volume occurs, and at the same time, an inelastic collision state appears between the plug, the gas plug, and the liquid with a relative speed difference of 100 m / s. In the tube 10, a flow of a coupled oscillator having a rapid change in acceleration, which consists of three phases of solid, liquid, and gas, is generated, and the plug is efficiently transported.
In particular, there is a difference in density between objects in the inertial fluid, and sudden changes in acceleration (sudden start and stop) that can be expressed as collisions cause pressure differences between the objects, making it possible to transport things like iron ingots. To do.
The water hammer phenomenon refers to a water hammer phenomenon, which is a collision phenomenon in which it is not negligible that water is compressed and its volume is reduced.
[0029]
The fluid flowing through the discharge pipe 10 is mixed at a low concentration with a plug portion (high concentration portion) in which clay is mixed at a high concentration by repeating the above-described falling and rising cycles of the suction port portion 12. The plug flow is alternately generated (the fresh water portion and the gas plug portion. When the water vapor gas plug portion goes downstream, it is cooled by external water and disappears, and the upstream portion is vacuumed).
[0030]
In addition, as described above, an expansion wave (vacuum wave: expanding wave) and a pressure wave (compressive wave) are alternately generated in the low concentration part between the high concentration part and the high concentration part, and the fluid is The discharge pipe 10 flows in an oscillating flow state that vibrates vigorously in the discharge pipe 10, and high concentration clay flows almost without contact with the pipe wall of the discharge pipe 10, that is, in a state where the pipe resistance is low. However, clay (sediment) can be transported well. Because it was confirmed that even when the pipe length was as long as 1000 to 1500 L (length) / D (diameter), it was possible to discharge sediment with high concentration at an average flow velocity of 1.3 m / sec. I understand. Incidentally, the water head difference is 5.0 m, C _v When a clay slurry of 7 vol% and ρ = 1.1 was flowed at L / D = 100, the tube was clogged due to adhesion of the slurry to the inner wall of the tube and the viscosity of the slurry itself, and the flow rate became zero.
It should be noted that the situation where the fluid flows while vigorously oscillating in the discharge pipe 10 is as follows. As a result of observing a part of the discharge pipe 10 transparently, the water column separation length of each place reaches 50 cm, and the negative pressure for several seconds. When a reverse flow phenomenon occurs, water column separation disappears due to pressure recovery from the upstream portion, and the length becomes 0 cm, a rapidly accelerated fluid reaching 100 m / s collides with the downstream portion. In this way, it was confirmed that the pipe flowed down with vigorous vibration.
FIG. 9 shows a correlation diagram between the pipe loss and the true volume concentration (solid phase ratio). λ represents the resistance coefficient of the entire system. In the calculation formula, there are several dozens of coefficients related to flow and the solution diverges. FIG. 9 shows that a discharge pipe having a diameter of 15 cm and a length of 150 m is used, and a fluid having a solid head ratio of 5.0 m and a hydrodynamic gradient i = 0.033 is transported (fluid) at various solid fractions. The results are shown.
When the fluid is a Newtonian fluid, it flows without any trouble at a flow velocity of 3.6 m / sec.
In the case of a Bingham fluid, if the operation (the raising / lowering operation of the vertical pipe portion 13 or the like) as in the present embodiment is not performed (the pulsation-free condition is shown in the figure), the tube will soon be blocked and will not flow.
By performing the above operation of the present embodiment, the resistance coefficient did not increase so much, and it was possible to discharge and transport not only Bingham fluid but also a plastic fluid having a solid fraction of about 30%.
[0031]
As described above, expansion waves (liquid or gaseous) and pressure waves (liquid) are alternately generated in the low-concentration portions between the plug portions generated at intervals in the discharge pipe 10, and solid / Flowing in a three-phase state of liquid and gas (including water column separation) is as if a freight car (high concentration part) connected by a coupler (low concentration part) that is descending by gravity on a long downhill. Is similar to the situation when suddenly starting and stopping in the middle of a hill by a locomotive, and with a lot of couplers extending and contracting, it can start and stop with less energy, as well as less energy, That is, due to the synergistic effect (synergistic effect) of the horizontal force of gravity due to the slope of the slope and the small inertial force, a high concentration, high viscosity fluid does not settle and accumulate in the discharge pipe 10 at an average low speed of 1.3 m / sec It flows to the discharge port.
Even if the wear amount of the pipe is judged from an actual measurement value proportional to the square of the flow velocity, it is clear that the durability of the entire system is improved several times.
[0032]
Further, as described above, water vapor condenses and is taken into water. On the other hand, the blown compressed air partially dissolves in water, but most of the compressed air is dispersed as small particles (microballoons) in the fluid film between the tube wall of the discharge pipe 10 and the solid. Discharged. In this way, the air is dispersed in the fluid film adhering to the tube wall of the discharge pipe 10, thereby further reducing the pipe resistance of the fluid and contributing to the good discharge of the fluid. When carbon dioxide gas is used as the compressed gas, it dissolves in water at a high pressure and foams at a low pressure, making it easier to create a flow in the above-described coupled oscillator state.
In this way, even a hard and very viscous deposit in which a high concentration wash load with a solid phase ratio of about 30% is consolidated can be discharged well.
[0033]
Note that the compressed gas and water vapor are supplied or shut off from the compressed gas supply unit 74 and the water vapor supply unit 73 by an electromagnetic valve (not shown), and the timing of opening and closing the electromagnetic valve is the timing of raising and lowering the suction port 12. That is, it is controlled so as to be performed in accordance with the drive timing of the elevating device 38 constituted by a crank mechanism or the like.
[0034]
Although not shown in the drawing, by providing a spiral projection on the inner surface of the discharge pipe 10 and forming a riblet (grooves and projections alternate in a spiral), the rifle ball is fired while rotating. In the same way as the resistance is reduced, the plug and fluid in the pipeline rotate, further reducing the resistance of the plug and discharging deposits more smoothly. In addition, the expansion and contraction of the tube causes the cross section of the tube to increase or decrease. This increase or decrease of the cross section of the tube further enhances the above rotation (spin effect). The speed difference will increase).
[0035]
By the way, as described above, cavitation and water hammer phenomenon occur in the fluid, and the destructive force acting on the discharge pipe 10 increases. An example of a mechanism for preventing damage to the discharge pipe 10 and enhancing the durability of the system will be described with reference to FIGS.
First, basically, in order to be able to absorb the destructive force acting on the discharge pipe 10 by the discharge pipe 10 itself, the discharge pipe 10 has elasticity such as rubber having an elastic coefficient E of about E = 4 GPa with an organic substance. It is recommended to use a material with a large material.
When using a large-diameter discharge pipe 10 having a tube diameter of 100 cm or more, a flexible pipe structure in which a trapezoidal rubber plate reinforced with an iron plate is wound in a spiral shape with the iron plate side outward and joined. It is preferable to use one formed in (see FIG. 10).
[0036]
In FIG. 7, reference numeral 80 denotes a float, which is disposed at a bent portion between the vertical pipe portion 13 and the horizontal pipe portion 14 of the discharge pipe 10 and imparts buoyancy to the discharge pipe 10. The float 80 is connected to the compressed air supply unit 74 on the carriage 36 by a pipe 81, and compressed air is supplied and discharged.
Reference numeral 82 denotes a pressure absorbing portion which communicates with the inside of the discharge pipe 10 and absorbs pressure increase and pressure reduction in the discharge pipe 10 to reduce the destructive force applied to the discharge pipe 10. The pressure absorption part 82 is provided at an appropriate location of the horizontal pipe part 14 of the discharge pipe 10 and is connected in three in the illustrated example.
[0037]
FIG. 8 shows a specific example of the pressure absorbing unit 82.
In this example, the pressure absorbing portion 82 uses a structure similar to a car tire.
Reference numeral 84 denotes a holding ring made of a metal such as aluminum or iron, and the discharge pipe 10 is inserted through the holding ring 84. The holding ring 84 is fixed on the outer periphery of the discharge pipe 10 by appropriate means. The holding ring 84 communicates with the inside of the discharge pipe 10 through the hole 85 in a liquid-tight and air-tight manner.
[0038]
Reference numeral 86 denotes an outer tube, which is fitted on the outer periphery of the holding ring 84 and constitutes a sealed tube space together with the holding ring 84, like a car tire. Reference numeral 87 denotes an inner tube, which is disposed in the outer tube 86.
Compressed air and water vapor are supplied into the outer tube 86 through a valve 88 and a connecting hose 89 provided on the holding ring 86. The outer tubes 86 of the three pressure absorbing portions 82 are connected to each other by a connecting hose 89, and the outer tube 86 of the outermost pressure absorbing portion 82 is passed through a double pipe 75 having the same structure as shown in FIG. Compressed air and water vapor are supplied. The double pipe 75 is connected to a compressed air supply unit 74 and a water vapor supply unit 73 provided on the carriage 90 (FIG. 7) via a connection pipe.
[0039]
Compressed air is supplied to the inner tube 87 through a valve 91 provided on the holding ring 84, a valve 92 provided on the inner tube 87, a hose connecting these, and a hose 93. The hose 93 is connected to a compressed air supply unit 95 provided on the carriage 90. Further, the inner tubes 87 of the three pressure absorbing portions 82 are communicated with each other by a connecting hose 96.
[0040]
The pressure absorbing portion 82 is configured as described above.
The pressure in the inner tube 87 is in equilibrium with the pressure in the inner space of the outer tube 86 and serves to hold the outer tube 87 so as not to be crushed. However, the inner tube 87 may not be provided in some cases.
When an expansion wave is generated in the discharge pipe 10 and the pressure is reduced, compressed air and water vapor flow into the discharge pipe 10 from the outer tube 86 through the hole 85, thereby causing a sudden deformation of the discharge pipe 10. Is prevented. Further, when a relatively large stone 97 or the like flows in the discharge pipe 10, the water vapor supplied into the discharge pipe 10 is crushed and the pressure is reduced, so that the low-pressure water column separation unit 98 is formed on the flow direction side of the stone 97. This facilitates the formation of a coupled oscillatory flow consisting of the three phases of solid, liquid, and gas, and more efficiently transports plugs and stones.
[0041]
When a pressure wave is generated in the discharge pipe 10 and the pressure rises, water flows into the outer tube 86 and absorbs a sudden increase in pressure in the discharge pipe 10, so that the discharge pipe 10 Can be prevented.
Thus, by providing the pressure absorption part 82, even if cavitation or water hammer phenomenon occurs in the fluid, the pressure change can be absorbed by the pressure absorption part 82, and the pulsation state necessary for solid transportation can be maintained. And damage to the discharge pipe 10 can be prevented as much as possible.
[0042]
Since the pressure absorbing part 82 also serves as a float, the horizontal pipe part 14 can be easily placed at a location below the hydrodynamic gradient by arranging it at appropriate intervals in the horizontal pipe part 14. Become.
In addition, the pressure absorption part 82 is not limited to the said structure. For example, it may be simply formed in a float shape and communicated with the inside of the discharge pipe 10 through a hole or an appropriate pipe so as to absorb the pressure change in the discharge pipe 10.
[0043]
In the case of dredging in a dam lake or the like, a sudden water flow of 3 m / sec or more occurs in the dam lake during a large flood, and an extremely large force acts on the discharge pipe 10 and the discharge pipe 10 may be damaged greatly. There is.
In the case of such a large flood, the entire discharge pipe 10 may be submerged in the bottom of the lake.
For that purpose, the wire suspended from the carriage 36 is loosened, the double pipe 75 and the pipes 81 and 93 are loosened, and the gas in the float 80 and the pressure absorbing portion 82 is discharged to discharge the pipe. Let 10 sink to the bottom of the lake. Since the flow velocity of the water flow is small at the bottom of the lake, damage to the discharge pipe 10 can be reduced.
[0044]
In the above embodiment, the sediment dredged in the dam lake has been described as an example, but the present invention is not limited to this. Naturally, it can also be used by storing a water level difference (pressure difference) between the suction side and the discharge side in storage areas such as ponds and lakes and dredging in the sea.
Alternatively, even when coal or iron ore that is a cargo in a tanker is discharged from the tanker, after injecting water into the tanker, the coal and iron ore are externally mixed with the water flow with the same structure as the above embodiment. It can also be applied to a deposit transport mechanism that transports deposits accumulated in a water storage place to the outside.
In addition, due to the fact that an iron ingot of ρ = 7.4 has been trapped, the above mechanism that gives a sudden change in acceleration due to a sudden pressure difference in the pipeline is a mechanism for collecting useful substances in the deep sea and methane hydrate. It can also be applied.
In addition, since a coupled oscillatory flow of solid, liquid and gas is generated, it is suitable for long-distance transportation of crude oil.
In particular, sudden pressure changes in the pipeline due to the sudden closing and opening of the valve at the inlet of the pipeline lead to pulsation of the heart, and the mechanism of the expansion wave at the inlet is It can be applied to the transport of red blood cells and platelets, and at that time, it contributes to the activation (stimulation) of the deformability of red blood cells and the aggregation ability of platelets.
[0045]
While the present invention has been described in detail with reference to a preferred embodiment, the present invention is not limited to this embodiment, and it goes without saying that many modifications can be made without departing from the spirit of the invention. .
[0046]
【The invention's effect】
According to the present invention, as described above, an expansion wave (a low-pressure part generated in a liquid state or a gas state: a vacuum wave), a pressure wave is generated in a low-concentration part between plug parts generated at intervals in the transport pipe. A freight car connected by a coupler (low-concentration part) as a liquid (liquid) is generated alternately, resulting in a three-phase coupled oscillatory flow consisting of solid, liquid, and gas (including water column separation). Similar to the situation when the (high concentration part) is suddenly started and stopped by the locomotive, it can start or stop with less energy by the extension and contraction of the coupler made of spring, Even with a small amount of energy, that is, a small inertial force, a synergistic effect with gravity (water head difference; pressure difference) produces an effect that a fluid of high concentration and high clay flows in the transport pipe for a long distance.
[Brief description of the drawings]
FIG. 1 is an explanatory diagram showing an example of a dredging mechanism in a dam lake,
FIG. 2 is an explanatory diagram showing the structure of the Miwa dam,
FIG. 3 is an explanatory view showing a fixing mechanism in a dam hole portion of a transport pipe (discharge pipe);
FIG. 4 is an explanatory diagram of a trolley,
FIG. 5 is an explanatory view showing the structure of a cup-shaped body in the suction port portion;
FIG. 6 is an explanatory view showing the structure of a double pipe;
FIG. 7 is an explanatory diagram of a pressure absorption unit,
FIG. 8 is an explanatory diagram showing further details of the pressure absorbing unit.
FIG. 9 is a correlation diagram between pipe loss and solid phase rate.
FIG. 10 is a cross-sectional view showing an example of a discharge pipe.
[Explanation of symbols]
10 Discharge pipe
12 Suction port
13 Vertical pipe
14 Horizontal pipe
18 Discharge port
20 water storage place
22 Sediment
24 Weir hole
30 discharge part
36 trolley
37 crane
38 Lifting device
60 Cup-shaped body
72 Chisel
73 Water vapor supply unit
74 Compressed air supply unit
75 Double pipe
82 Pressure absorber

Claims

A suction port portion that is opened to face the bottom of the water on which deposits are accumulated in a water storage place, a vertical pipe portion that extends in a vertical direction from the suction port portion, and a horizontal pipe that extends substantially horizontally from the upper portion of the vertical pipe portion to store water. It has a horizontal pipe part that opens toward the discharge part that is lower than the place, and the horizontal pipe part is disposed so as to penetrate liquid-tightly through a hole provided at a position lower than the water level of the water storage place At the same time, it is supported at a position below the hydrodynamic gradient line in the water in the reservoir, and when the deposit is transferred, the suction port is required with respect to the bottom surface of the reservoir by the lifting device. A transport pipe that is moved up and down so as to come in and out of the cycle of
A cup-shaped body that is provided in the suction port portion of the transport pipe, and that the suction port portion is movably moved in the up and down direction, and has a shape opened downward;
A water vapor supply section for supplying water vapor into the cup-shaped body;
A deposit transport mechanism, comprising: a compressed gas supply unit that supplies compressed gas into the cup-shaped body.

The suction port side is lowered together with the cup-like body, the suction port bites into the bottom surface of the water, and the suction port is suddenly closed, whereby the pressure on the suction port side is caused by the inertial force of the fluid in the transport pipe. The expansion wave is generated by lowering, water column separation occurs sequentially from the suction port side to the low concentration part in the transport pipe,
Next, the suction port is raised with respect to the cup-shaped body, and the high concentration portion that has entered the suction port is sucked as a plug, and a small amount of compressed gas is supplied from the compressed gas supply unit to the cup-shaped body, By supplying a larger amount of water vapor than compressed gas from the water vapor supply unit into the cup-shaped body, high-concentration sediment at the bottom of the water, water in the cup-shaped body, compressed gas, and water vapor flow into the suction port. A plug and a gas plug made of high-concentration deposits are formed to raise the vertical pipe part,
Next, the cup-shaped body is raised, and the supply of the compressed gas and water vapor is stopped. As a result, water vapor in the gas plug portion is condensed, the volume of the gas plug is reduced, and the suction port portion is rapidly opened. As the fresh water flows into the suction port, the pressure on the suction port side rises, a pressure wave is generated, and the cycle for condensing the water column separation unit is repeated, so that the transport pipe is made of solid, liquid, and gas. The deposit transport mechanism according to claim 1, wherein a coupled oscillator-like flow is created to transport the deposit to the discharge section.

The deposit transport mechanism according to claim 1, wherein the compressed gas supply unit supplies compressed air or carbon dioxide gas.

There is a trolley floated at the water storage place, and a suspension device that supports the transport pipe and the transport pipe are connected to and separated from the bottom surface in a required cycle with respect to the water bottom. The deposit transport mechanism according to claim 1, 2 or 3, wherein an elevating device that moves up and down as described above, the water vapor supply unit, and the compressed gas supply unit are arranged.

5. The deposit transport mechanism according to claim 1, further comprising a pressure absorbing portion that is provided in communication with the inside of the transport pipe and absorbs increase / decrease in pressure in the transport pipe.

A suction port portion that is opened to face the bottom of the water on which deposits are accumulated in a water storage place, a vertical pipe portion that extends in a vertical direction from the suction port portion, and a horizontal pipe that extends substantially horizontally from the upper portion of the vertical pipe portion to store water. It has a horizontal pipe part that opens toward the discharge part that is lower than the place, and the horizontal pipe part is disposed so as to penetrate liquid-tightly through a hole provided at a position lower than the water level of the water storage place At the same time, it is supported at a position below the hydrodynamic gradient line in the water in the reservoir, and when the deposit is transferred, the suction port is required with respect to the bottom surface of the reservoir by the lifting device. A transport pipe that is moved up and down so as to come into contact with and separate from each other in a cycle, and a cup that is provided in a suction port portion of the transport tube and that has a shape that is opened downward so that the suction port portion can move in the vertical direction. And water vapor supply for supplying water vapor into the cup When using a sediment transport mechanism and a compressed gas supply unit for supplying compressed gas to said cup-shaped body,
The suction port side is lowered by the inertial force of the fluid in the transport pipe by lowering the suction port side together with the cup-shaped body, causing the suction port portion to bite into the bottom of the water and closing the suction port portion rapidly. To generate an expansion wave, causing water column separation sequentially from the suction port side to the low concentration part in the transport pipe,
Next, the suction port portion is raised with respect to the cup-shaped body, the high concentration portion that has entered the suction port is sucked as a plug, and a small amount of compressed gas is supplied from the compressed gas supply portion to the cup-shaped body, By supplying a larger amount of water vapor than compressed gas from the water vapor supply unit into the cup-shaped body, high concentration sediment at the bottom of the water, water in the cup-shaped body, compressed gas and water vapor are caused to flow into the suction port, Forming a plug and a gas plug made of deposits of concentration to raise the vertical pipe part,
Next, the cup-shaped body is raised, the supply of the compressed gas and water vapor is stopped, the water vapor in the gas plug part is condensed, the volume of the gas plug is reduced, and the suction port part is rapidly opened. By repeating the cycle of flowing fresh water into the suction port, increasing the pressure on the suction port side, generating a pressure wave and condensing the water column separation unit, the transport pipe is coupled with solid, liquid, and gas. A deposit transfer method comprising generating an oscillatory flow and discharging a deposit to the discharge section.

The deposit transfer method according to claim 6, wherein compressed air or carbon dioxide gas is supplied into the cup-shaped body from the compressed gas supply unit.