JP4298824B2

JP4298824B2 - Gas-liquid dissolution and mixing equipment

Info

Publication number: JP4298824B2
Application number: JP30750698A
Authority: JP
Inventors: 雅一柏
Original assignee: Idec Corp
Current assignee: Idec Corp
Priority date: 1997-10-28
Filing date: 1998-10-28
Publication date: 2009-07-22
Anticipated expiration: 2018-10-28
Also published as: JPH11197475A

Description

【０００１】
【発明の属する技術分野】
この発明は、各種の気体の気泡を液体中に分散させたり、加圧下の液体中で気体を反応させたり、溶解させるための気液溶解混合装置に関する。
【０００２】
【従来の技術】
従来、一般に気体を液体中に分散溶解させる方法として、気体中に液体の噴流を通過させるエゼクター式気泡発生装置や、気体を溶解させたい液体を加圧タンク内に一旦収容し、この液体中に大量の気体を送り込み、この加圧タンク内で気液反応及び気体の溶解を行わせる気液溶解混合装置がある。さらに、液体ポンプの吸水側に気体を送り込むものもある。
【０００３】
また、本願出願人による、特許第２５５４６０８号等に示すように、液体の流路に設けられたベンチュリ管状の絞り部により流路の一部を絞り、この絞り部の下流側で徐々にこの流路を広げるとともに、上記絞り部のわずかに下流側で、負圧になった気体流入口から気体を吸引し気液混合流を形成し、この流路の下流にノズル部を設けて、このノズル部の上流側の流路内の圧力を上昇させ、このノズル部の上流側の流路内部で液体に気体を加圧溶解させ、気体が溶解した気液混合流を、上記ノズル部を経て噴射して微細気泡を得る気液溶解混合装置も提案されている。
【０００４】
【発明が解決しようとする課題】
上記従来の技術のエゼクターを用いたものは、液体噴射ノズルを気体流路の絞り部の中心に正確に位置合わせしなければならず、装置の構造が複雑になり、気液の混合割合や溶解量も十分なものではなかった。特に、安定に気液混合が行える気液比（気体流量／液体流量×１００）は３０％以下であった。また、上記従来の技術の加圧タンクを用いたものの場合、加圧タンク内の液体は、止まった状態で、タンク内に収容された液体に気体を溶解させなければならず、連続的に液体に気体を溶解させることができないものであった。従って、気液の高接触状態を加圧タンク内で得るには、大量の気体を加圧タンク内に注入しなければならず、気体の無駄が多く効率の悪いものであった。特に高価な気体を用いる場合には、コスト上昇の原因となっていた。さらに、加圧タンク内で、気体を溶解させるには、加圧タンク内の液体と注入する気体との圧力を適切に調整しなければならず、この調整が、気温、気圧、液温等により変化するため、これらのパラメータが変動する度に、各圧力調整を行わなければならないという問題があった。さらに、液体ポンプの吸水側に気体を供給する場合、ポンプ内でキャビテーションガ生じ、ポンプの構造や材質が制限され、コストがかかる上、効率も悪いものであった。
【０００５】
また上記本願出願人による気液溶解混合装置の場合、上記他の従来技術と比較して、小型で効率の良い気液溶解混合装置が得られるものであるが、液体流れの絞り部のわずかに下流で、気体が液体流れに対して垂直に流入するため、気体流れが液体流れに影響し、流入効率の向上の妨げとなっていた。特に、液体の圧送圧が０．２ＭＰａ以下の場合、気体の流入が液体流れに影響し、安定した気液混合が得られない場合があった。また、この場合も安定に気液混合が行える気液比（気体流量／液体流量×１００）は３０％以下であった。
【０００６】
この発明は、上記従来技術の問題点に鑑みて成されたもので、効率よく連続的に大量に気体を液体中に溶解混合させることができる気液溶解混合装置を提供することを目的とする。
【０００７】
【課題を解決するための手段】
この発明は、液体の流路に設けられたベンチュリ管等の絞り部と、この絞り部につづいてこの流路を徐々に広げた広がり部と、上記絞り部内で上記液体の流れ方向に開口した気体流入管とを設け、上記広がり部の下流に設けられ流路中の液体と上記気体流入管から流入した気体とを混合する管路等からなる混合部と、この混合部の出口側に設けられたバルブや固定絞りまたはノズル部等の出口絞りとを有する気液溶解混合装置である。上記絞り部には、液体の流れ方向に断面積がほぼ一定の平行部を所定長設けられ、この平行部の中央部に上記気体流入管が位置している。この気体流入管は上記絞り部の液体流れ方向に配置され、上記絞り部の入口部から上記気体流入管の開口部までの距離、及び上記気体流入管の開口部から上記絞り部の出口部までの各距離は、上記絞り部の直径の各々１．５〜４倍、管路抵抗を考えると好ましくは１．５〜２倍である。そして、上記絞り部の長さは上記絞り部の直径の３〜８倍、管路抵抗を考えると好ましくは３〜４倍である。これは、絞り部の長さが上記値より短くなると、気体の吸引が不安定になり、また絞り部の長さが絞り部の直径の８倍より長くなると、気体吸引量が大きく減少してしまうからである。
【０００８】
また、上記液体流路の上記絞り部の上流側に、液体配管を介して液体を圧送するポンプ等の液体圧送手段を接続し、上記気体流入管の上流側には、気体配管を介してコンプレッサやボンベ等の気体圧送手段を接続したものである。
【０００９】
さらに、上記混合部は、流路が段階的に緩急を繰り返す勾配に形成され、上から下へ流体が流れるものである。上記混合部の途中に、上記出口絞りよりも断面積の大きい中間絞りを設けたものである。また上記混合部に、余剰気体を外部へ逃がす上方に突き出した分岐流路を設けたものである。上記混合部の下流に流路が分岐した分岐流路が設けられ、この分岐流路に上記出口絞りが設けられたものである。また、上記混合部の下流に上記出口絞りを設け、この出口絞りの下流に流路が分岐した分岐流路を設けたものである。
【００１０】
さらに、上記混合部は、液体の流れ方向に直列に複数接続されている。上記混合部は、液体の流れ方向に直列に複数接続し、上記各混合部は、気体を送る気体配管と液体を送る液体配管により別々に接続されている。また、上記混合部の少なくとも一つの最上段にバルブを設け、上記液体圧送手段の停止時に少なくとも３秒間上記バルブを解放するものである。
【００１１】
この発明の気液溶解混合装置は、ベンチュリ管ののど部等の絞り部で気体を気体流入管から流路に吸引する際に、気体流入管及びその開口部を液体の流れ方向に向けて、液体流れの中央部で液体の流れ方向に気体を吸引して流入させている。これにより、絞り部の中央部に吸引された気体流れが形成され、その外側に液体流れが形成され、安定的に効率よく気体吸引を行うものである。特に、気体流入管は、流路の絞り部のほぼ中央部に位置し、所定長さの絞り部の上流側で液体流れが安定した位置で気体を流入させ、気体が流入した液体流れをさらにその気体流入管の開口部より下流の絞り部により安定させ、気体の流入をより安定させるものである。
【００１２】
【発明の実施の形態】
以下この発明の気液溶解混合装置の実施の形態について図面に基づいて説明する。図１、図２はこの発明の第一実施形態を示すもので、図示するように、この実施形態の気液溶解混合装置は、水等の液体中に、空気や酸素又はオゾンその他不活性ガス等、種々の気体を混合する吸引器１０を有し、この吸引器１０の流入部１１に液体配管１２の先端部が取り付けられている。また、吸引器１０の流出部１３には、気液を混合させる混合部として、液体が上から下へ段階的に流れ落ちる混合部である気液混合槽１４が接続され、気液混合槽１４の下部の出口部１５に、管路１６が接続されている。この管路１６の先端部には、出口絞り１８が設けられ、出口絞り１８の下流にも短い管路２０が接続されている。
【００１３】
吸引器１０内には、図２に示すように、流路を緩やかに絞ったのど部である絞り部２２が中央部に設けられたベンチュリ管状の流路２４が形成されている。このベンチュリ管状の流路２４の下流側には、広がり部２６が形成されている。絞り部２２は、円筒状に形成され、絞り部２２は液体の流れ方向に断面積がほぼ一定の平行部２８を所定長備え、この平行部２８のほぼ中央部に、気体流入管３０が位置している。
【００１４】
この気体流入管３０は流路２４内では液体流れ方向に配置され、吸引器１０の流入部１１部分で直角に折れて外部に出ている。なお、この気体流入管３０は、空気を大気圧下で吸引する場合は外気に開放しておけば良く、また特定の気体や加圧して大量の気体を送り込む場合は、ボンベやコンプレッサ等に接続される。
【００１５】
吸引器１０の絞り部２２の入口部２２ａから気体流入管３０の開口部３０ａまでの距離、及び気体流入管３０の開口部３０ａから絞り部２２の出口部２２ｂまでの各距離は、絞り部２２の流路の直径の各々１．５〜４倍、管路抵抗を考えると好ましくは１．５〜２倍である。絞り部２２の平行部２８の長さは、絞り部２２の流路の直径の３〜８倍であり、管路抵抗を考えると好ましくは３〜４倍である。
【００１６】
広がり部２６の下流側に接続された気液混合槽１４は、上から下に液体が段階的に流れ落ちる流路３２が形成されたものである。流路３２は、水平部と垂直部とが交互に形成され、水平部を形成する隔壁３３により形成されている。そして、流路３２の上部の入口部３４に吸引器１０が接続され、下方の出口部１５側に管路１６が接続されている。気液混合槽１４の出口部１５近傍には、余剰気体を上方へ逃がすための垂直方向の分岐流路を設けた余剰気体分離部３６が形成され、余剰気体分離部３６の上方には、余剰気体を外部へ逃がす開口部３８が設けられている。
【００１７】
この実施形態の気液溶解混合装置の作用について以下に説明する。先ず、液体配管１２から吸引器１０の流入部１１に流入した水等の液体は、流路２４の絞り部２２で加速されて、一旦静圧が低下し、広がり部２６を経て流速が遅くなり再び静圧が増大する。このとき、気体流入管３０の開口部３０ａから流路２４へ、空気等の気体が送り込まれる。ここで、絞り部２２の平行部２８の断面積Ｓ _Aと出口絞り１８の総断面積Ｓ _Bは、以下の式を満たすものであれば良い。
Ｐ_A＜Ｐ_G （１）
Ｐ_Gは、気体流入管３０から流入する気体の圧力。
Ｐ_Aは、流体力学上のベルヌーイの定理と連続の式により以下の式（２）により与えられ、気体流入管３０の開口部３０ａのある位置での平行部２８中の静圧。
Ｐ_A＝（１−Ｓ_Ｂ ^２／Ｓ_Ａ ^２）Ｐ₁＋（δＰ＋Ｐ_B）Ｓ_Ｂ ^２／Ｓ_Ａ ^２（２）
ここで、Ｐ₁は平行部２８に流入する液体の総圧、δＰは平行部２８からから出口絞り１８までの圧力損失、Ｐ_Bは出口絞り１８の出口側の静圧である。
【００１８】
従って、上記式（１）、（２）を満たす様に液体の圧送圧、気体流入管３０及び出口絞り１８等の大きさ等を設定することにより、液体中に気体を効率的に混合し溶解させる最適な条件が得られるものである。また、気液混合槽１４は、加圧下で、液体に気体が溶解し飽和状態となるまで気液の接触時間が得られるものであればより好ましい。気液の接触時間は混合部の体積に依存するので、気液混合槽１４の長さがある程度長い方がよい。また、気液溶解や気液の反応には、所定の圧力が必要となる場合があり、出口絞り１８は、気液混合槽１４の内部を所定の圧力に保つ働きも有する。気液混合槽１４の内部の圧力は、気液混合槽１４の断面積が十分に広い場合、次の式（３）により表される。
Ｐ_Ｃ＝ρＵ²／２＋Ｐ_Ｂ＋δＰ_２（３）
ここで、Ｐ_Ｃは気液混合槽１４内部の圧力、ρは液体の密度、Ｕは出口絞り１８での液体の流速、Ｐ_Ｂは出口絞り１８の出口側の静圧、δＰ_２は気液混合槽１４から出口絞り１８までの圧力損失である。
【００１９】
気体流入管３０の開口部３０ａから吸引された気体は、気泡となって流路２４中の液体とともに気液混合槽１４に流れ、気泡となった気体は、気液混合槽１４の静圧が絞り部２２より高いので液体中に溶解していく。そして、気液混合槽１４から管路１６を経て出口絞り１８で再び静圧が低くなり、溶解していた気体が微細気泡となって液体中に析出する。また、余剰気体は余剰気体分離部３６の上方の開口部３８から外部へ逃がされる。さらに、溶解し切らなかった気泡は、出口絞り１８で細かく剪断され、数十〜数百μｍの微小気泡となって液体中に分散される。
【００２０】
この実施形態の気液溶解混合装置によれば、吸引器１０の絞り部２２の平行部２８の中央に気体流入管３０が同軸的に配置され、その気体流入管３０から効率よく安定に気体を液体中に吸引混合することができる。特に、気体流入管３０の開口部３０ａを液体の流れ方向に向けて、液体流れの中央部で液体の流れ方向に気体を流入させているので、安定に効率よく気体吸引が可能となる。また、気体流入管３０は、流路の絞り部２２のほぼ中央部に位置し、絞り部２２の上流側の平行部２８で液体流れが安定し、その安定した液体流れの中央部に気体が流入し、液体流れをさらにその気体流入管３０の開口部３０ａより下流の平行部２８により安定させ、気体の流入をより安定させるものである。
【００２１】
次にこの発明の第二実施形態について図３を基にして説明する。ここで、上述の実施形態と同様の部材は同一符号を付して説明を省略する。この実施形態の吸引器１０は、気体流入管３０が、吸引器１０に対して直線状に配置され、吸引器１０が流路２４の流入部１１で直角に折れているものである。この実施形態によっても上記実施形態と同様の効果を得ることができる。
【００２２】
次にこの発明の第三実施形態について図４を基にして説明する。ここで、上述の実施形態と同様の部材は同一符号を付して説明を省略する。この実施形態の気液溶解混合装置は、上記第一実施形態の気液混合槽１４の代わりに、気液を混合させる混合部として管路４０が設けられたものである。この実施形態によれば、吸引器１０に管路４０を接続して管路４０の先端部に出口絞り１８を取り付けるだけで気液溶解混合装置を構成することができ、構成が簡単であり、組み立てや取り扱いが容易である。
【００２３】
次にこの発明の第四実施形態について図５を基にして説明する。ここで、上述の実施形態と同様の部材は同一符号を付して説明を省略する。この実施形態の気液溶解混合装置は、気液混合槽１４の出口部１５に接続された管路１６が、途中で分岐し、複数の分岐管路４２が設けられたものである。分岐管路４２の先端部には、各々出口絞り１８が取り付けられ、出口側の管路４３から気体溶解液が出る。
【００２４】
この実施形態の気液溶解混合装置は、複数の管路に分岐したので、異なる供給先へも各々気体溶解液を供給することができ、より広い用途に使用可能である。
【００２５】
次にこの発明の第五実施形態について図６を基にして説明する。ここで、上述の実施形態と同様の部材は同一符号を付して説明を省略する。この実施形態の気液溶解混合装置は、上記第四実施形態の分岐前の管路１６に出口絞り１８を設け、出口絞り１８を通過した気液混合流を分岐部で複数の管路４４に分割して、気液混合流を供給するものである。
【００２６】
次にこの発明の第六実施形態について図７を基にして説明する。ここで、上述の実施形態と同様の部材は同一符号を付して説明を省略する。この実施形態の気液溶解混合装置は、上記第一実施形態の吸引器１０に、液体配管５０を介して液体圧送手段であるポンプ５２を備える。ポンプ５２の上流側には、液体配管５４を介して給水源５６が接続され、被処理水５８を吸引器１０に圧送可能に設けられている。
【００２７】
吸引器１０の気体流入管３０は、気体配管６０を介してコンプレッサ６２に接続されている。また、吸引器１０の流出部１３には、液体が上から下へ段階的に流れ落ちる混合部である気液混合槽１４が接続され、気液混合槽１４の下部の出口部１５に、管路１６が接続されている。この管路１６の先端部には、出口絞り１８が設けられ、出口絞り１８の下流に管路２０が接続されている。管路２０の先端には、被処理水６４を収容する処理水槽６６が設けられている。
【００２８】
吸引器１０は、図２に示すものと同様の構成である。また、気液混合槽１４の上面には、電磁弁７０が取り付けられ、余剰気体分離部３６の上面にはバルブ７２が設けられている。さらに、余剰気体分離部３６の側面には、液体面を検知するセンサ７３，７４がその液面の下限と上限位置に設けられている。
【００２９】
この実施形態の気液溶解混合装置の作用について以下に説明する。給水源５６に溜められた被処理水５８は、液体配管５４，５０を介してポンプ５２により吸引器１０に圧送される。尚、吸引器１０に送られる被処理水５８に、気液混合に必要な所定の圧力がかかっている場合には、ポンプ５２を省略することもできる。吸引器１０では、流路２４の絞り部２２で加速されて、一旦静圧が低下し、広がり部２６を経て流速が遅くなり再び静圧が増大する。絞り部２２で液体の圧力が低下し、これにより気体流入管３０の開口部３０ａから流路２４へ、空気等の気体が送り込まれる。気体は、コンプレッサ６２により気体配管６０を介して気体流入管３０に所定の圧力で送られる。従って、絞り部２２の平行部２８の断面積と出口絞り１８の総断面積は、第一実施形態の（１）、（２）式を満たすものでなければならない。尚、コンプレッサ６２はボンベ等の他の気体圧送手段でも良い。
【００３０】
気体流入管３０の開口部３０ａから吸引された気体は、気泡となって流路２４中の液体とともに気液混合槽１４に流れ、気泡となった気体は、気液混合槽１４の静圧が絞り部２２より高いので液体中に溶解していく。そして、気液混合槽１４から管路１６を経て出口絞り１８で再び静圧が低くなり、溶解していた気体が微細気泡となって液体中に析出する。さらに、溶解し切らなかった気体は、出口絞り１８で細かく剪断され、数十〜数百μｍの微小気泡となって液体中に分散される。また、出口絞り１８は、気液混合槽１４の内部の圧力を保つ働きも有する。その条件は、気液混合槽１４の断面積が十分に広い場合、前述の式（３）により表される。
【００３１】
ここで、電磁弁７０は、ポンプ５２の停止時に少なくとも３秒間電磁弁７０を解放し、気液混合槽１４内部の加圧を逃がすものである。またバルブ７２は、センサ７３，７４の信号に対応させて液面が上限と下限の間に入り、排出される余剰気体中に液体が混合しない様に適宜操作するものである。この操作は、センサ７３，７４の信号により、液面が下限または上限にきたことを表示する手段を設けて、その表示により作業者がバルブ７２を操作するものや、センサ７３，７４からの信号により、自動的にバルブ７２を開閉する様にしたものでも良く、その制御方法は適宜選択可能である。なお、排気中に多少の液体の混入が許される場合等、排気中の液体が問題とならない場合は、センサ７３，７４とその操作手段は設けなくても良い。
【００３２】
この実施形態の気液溶解混合装置によれば、上記第一実施形態の効果に加えて、所望の液体圧送圧で、所望の気体を効率よく混合溶解させることができ、気体による処理液を効率よく製造することができる。そして、この実施形態によれば、気液比が４００％で、安定に気液混合を実現することができた。
【００３３】
次にこの発明の第七実施形態について図８〜図１０を基にして説明する。ここで、上述の実施形態と同様の部材は同一符号を付して説明を省略する。この実施形態の気液溶解混合装置は、上記第六実施形態の気液溶解混合装置の気液混合槽１４と同様の気液混合槽７６を複数並べ、気液混合流が各気液混合槽７６を直列に通過する様にしたものである。さらに、余剰気体分離部７８を気液混合槽７６の下流側に別体に設けている。各気液混合槽７６及び余剰気体分離部７８は各々配管８０により接続されている。配管８０は、気液混合槽７６の最下段の出口部１５から隣の気液混合槽７６の最上段の入口部３４をつなぐように配管されている。この実施形態では気液混合槽７６を３個連ねたが、この数は適宜設定可能なものである。
【００３４】
この実施形態の気液溶解混合装置の作用について以下に説明する。この実施形態の気液溶解混合装置も上記実施形態と同様の作用効果を有するが、気液混合槽７６を複数連ねることにより、気液の接触時間を長くとることができ、気液比をより大きくすることができる。ここで、気液の接触時間を長く取るには、気液混合槽の段数を多くすれば良いが、単に段数を多くしようとすると、気液混合槽の高さが高くなり、また、液体を気液混合槽の最上段にまで圧送するエネルギーを必要とし、効率が悪いものとなる。そこで、複数の気液混合槽７６を並べることにより、小型で、効率の良い気液混合槽を得ることができる。
【００３５】
次にこの発明の第八実施形態について図１１、図１２を基にして説明する。ここで、上述の実施形態と同様の部材は同一符号を付して説明を省略する。この実施形態の気液溶解混合装置は、上記第七実施形態の気液溶解混合装置と同様に気液混合槽７６を複数並べ、気体と液体が各気液混合槽７６を直列に通過する様にしたものである。この実施形態の場合、気体と液体は各々別々の気体配管８２と液体配管８４により各々隣接する気液混合槽７６に送られる。従って、気体配管８２は、気液混合槽７６の最下段の出口部１５の上方１５ａに接続され、隣の気液混合槽７６の最上段の入口部３４の上方３４ａに接続されて配管されている。また、液体配管８４は、気液混合槽７６の最下段の出口部１５の下方１５ｂに接続され、隣の気液混合槽７６の最上段の入口部３４の下方３４ｂに接続されている。気体配管８２と液体配管８４は、主に気体、液体を送るものであり、通常は気体配管８２で送られる気体中にも液体が混合し、液体配管８４で送られる液体中にも気体が混合している。
【００３６】
この実施形態によれば、上記実施形態と同様の効果に加えて、密度の小さい気体は主に上方の気体配管８２により隣の気液混合槽７６に送られ、密度の大きい液体は主に下方の液体配管８４により送られ、各々別々に移送される。これにより、各々管路抵抗が軽減され、圧送効率が向上する。
【００３７】
なお、この発明の気液溶解混合装置の混合部は上記実施形態以外の、固定またはフレキシブルな管路を用いても良く、気液混合槽の形状も任意に設定可能である。さらに、出口絞りの形状は上記実施形態以外に、一または複数の透孔を有したノズル部であっても良い。また絞り部は、段階的に内径が変化するものでも良い。また、混合部は、その途中に、上記出口絞りよりも断面積の大きい中間絞りを設けても良い。この絞り部の平行部はほぼ平行であれば良く、流れを安定化させる程度のものであれば良い。
【００３８】
【発明の効果】
この発明の気液溶解混合装置は、簡単な装置で効率よく安定に気体を液体中に吸引し、混合溶解させることができる。特に緩急を繰り返す混合部を設けることにより、気体がより効率よく効果的に溶解し、気体の無駄も少なくすることができる。
【図面の簡単な説明】
【図１】この発明の気液溶解混合装置の第一実施形態を示す概略図である。
【図２】この第一実施形態の気液溶解混合装置の吸引器の縦断面図である。
【図３】この発明の第二実施形態の気液溶解混合装置の吸引器の縦断面図である。
【図４】この発明の気液溶解混合装置の第三実施形態を示す概略図である。
【図５】この発明の気液溶解混合装置の第四実施形態を示す概略図である。
【図６】この発明の気液溶解混合装置の第五実施形態を示す概略図である。
【図７】この発明の気液溶解混合装置の第六実施形態を示す概略図である。
【図８】この発明の気液溶解混合装置の第七実施形態を示す概略図である。
【図９】この発明の気液溶解混合装置の第七実施形態の気液混合槽の断面図である。
【図１０】この発明の気液溶解混合装置の第七実施形態の気液分離部の断面図である。
【図１１】この発明の気液溶解混合装置の第八実施形態を示す概略図である。
【図１２】この発明の気液溶解混合装置の第八実施形態の気液混合槽の断面図である。
【符号の説明】
１０吸引器
１２液体配管
１６，２０管路
１４気液混合槽
２２絞り部
２４流路
２６広がり部
２８平行部
３０気体流入管[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a gas-liquid dissolution and mixing device for dispersing various gas bubbles in a liquid, or reacting or dissolving a gas in a liquid under pressure.
[0002]
[Prior art]
Conventionally, as a method of generally dispersing and dissolving a gas in a liquid, an ejector type bubble generating device that allows a jet of liquid to pass through the gas or a liquid in which a gas is to be dissolved are temporarily stored in a pressurized tank, There is a gas-liquid dissolution and mixing device that feeds a large amount of gas and causes gas-liquid reaction and gas dissolution in this pressurized tank. In addition, there are some which send gas to the water absorption side of the liquid pump.
[0003]
Further, as shown in Japanese Patent No. 2554608 by the applicant of the present application, a part of the flow path is throttled by a venturi-shaped throttle part provided in the liquid flow path, and this flow is gradually reduced downstream of the throttle part. While widening the path, slightly at the downstream side of the throttle part, a gas is sucked from the negative gas inlet and a gas-liquid mixed flow is formed, and a nozzle part is provided downstream of this flow path. The pressure in the flow channel upstream of the nozzle is increased, the gas is pressurized and dissolved in the liquid inside the flow channel upstream of the nozzle, and the gas-liquid mixed flow in which the gas is dissolved is injected through the nozzle. Thus, a gas-liquid dissolution and mixing device that obtains fine bubbles has also been proposed.
[0004]
[Problems to be solved by the invention]
In the case of using the above-described conventional ejector, the liquid jet nozzle must be accurately positioned at the center of the throttle part of the gas flow path, which complicates the structure of the device, and mixes and dissolves the gas / liquid. The amount was not enough. In particular, the gas-liquid ratio (gas flow rate / liquid flow rate × 100) at which gas-liquid mixing can be performed stably was 30% or less. Further, in the case of using the above-described conventional pressurized tank, the liquid in the pressurized tank must be dissolved in the liquid contained in the tank in a stopped state, and the liquid continuously The gas could not be dissolved. Therefore, in order to obtain a high gas / liquid contact state in the pressurized tank, a large amount of gas must be injected into the pressurized tank, which is wasteful and inefficient. In particular, when an expensive gas is used, the cost is increased. Furthermore, in order to dissolve the gas in the pressurized tank, the pressure of the liquid in the pressurized tank and the gas to be injected must be adjusted appropriately, and this adjustment depends on the temperature, atmospheric pressure, liquid temperature, etc. Since these parameters change, there is a problem in that each pressure adjustment must be performed each time these parameters change. Further, when gas is supplied to the water absorption side of the liquid pump, cavitation occurs in the pump, and the structure and material of the pump are limited, which is costly and inefficient.
[0005]
In addition, in the case of the gas-liquid dissolution and mixing apparatus by the applicant of the present application, a small and efficient gas-liquid dissolution and mixing apparatus can be obtained as compared with the above-described other conventional techniques, Since the gas flows in perpendicular to the liquid flow downstream, the gas flow affects the liquid flow, which hinders improvement in inflow efficiency. In particular, when the liquid feeding pressure is 0.2 MPa or less, inflow of gas affects the liquid flow, and stable gas-liquid mixing may not be obtained. In this case, the gas-liquid ratio (gas flow rate / liquid flow rate × 100) at which gas-liquid mixing can be performed stably was 30% or less.
[0006]
The present invention has been made in view of the above-described problems of the prior art, and an object thereof is to provide a gas-liquid dissolution and mixing device capable of efficiently and continuously dissolving and mixing a large amount of gas in a liquid. .
[0007]
[Means for Solving the Problems]
According to the present invention, a throttle part such as a venturi tube provided in a liquid flow path, a widened part that gradually widens the flow path following the throttle part, and an opening in the liquid flow direction in the throttle part. A gas inflow pipe, provided on the outlet side of the mixing section, which is provided downstream of the widened section and is composed of a pipe that mixes the liquid in the flow path and the gas flowing in from the gas inflow pipe. And a gas-liquid dissolution and mixing device having an outlet throttle such as a fixed valve or a nozzle. The throttle portion is provided with a predetermined length of a parallel portion having a substantially constant cross-sectional area in the liquid flow direction, and the gas inflow pipe is located at the center of the parallel portion. The gas inflow pipe is arranged in the liquid flow direction of the restrictor, and the distance from the inlet of the restrictor to the opening of the gas inflow pipe and from the opening of the gas inflow pipe to the outlet of the restrictor Are preferably 1.5 to 4 times the diameter of the throttle part, and preferably 1.5 to 2 times in consideration of the pipe resistance. The length of the throttle portion is 3 to 8 times the diameter of the throttle portion, and preferably 3 to 4 times considering the pipe resistance. This is because when the length of the throttle portion becomes shorter than the above value, the suction of gas becomes unstable, and when the length of the throttle portion becomes longer than eight times the diameter of the throttle portion, the amount of gas suction is greatly reduced. Because it ends up.
[0008]
Further, a liquid pumping means such as a pump for pumping liquid via a liquid pipe is connected to the upstream side of the throttle portion of the liquid flow path, and a compressor is connected to the upstream side of the gas inflow pipe via a gas pipe. Or a gas pumping means such as a cylinder is connected.
[0009]
Further, the mixing section is formed with a gradient in which the flow path repeats gradually and gradually, and the fluid flows from top to bottom. An intermediate throttle having a larger cross-sectional area than the outlet throttle is provided in the middle of the mixing section. Further, the mixing section is provided with a branch channel projecting upward to allow excess gas to escape to the outside. A branch channel having a branched channel is provided downstream of the mixing unit, and the outlet throttle is provided in the branch channel. Further, the outlet throttle is provided downstream of the mixing section, and the branch flow path is formed by branching the flow path downstream of the outlet throttle.
[0010]
Further, a plurality of the mixing units are connected in series in the liquid flow direction. A plurality of the mixing parts are connected in series in the liquid flow direction, and the mixing parts are separately connected by a gas pipe for sending gas and a liquid pipe for sending liquid. In addition, a valve is provided in at least one uppermost stage of the mixing unit, and the valve is released for at least 3 seconds when the liquid pumping means is stopped.
[0011]
The gas-liquid dissolution and mixing apparatus of the present invention, when sucking gas from the gas inflow pipe into the flow path at the throttle portion such as the throat of the venturi pipe, the gas inflow pipe and its opening are directed in the liquid flow direction, A gas is sucked and introduced in the liquid flow direction at the center of the liquid flow. As a result, a sucked gas flow is formed in the central portion of the throttle portion, and a liquid flow is formed on the outer side of the throttle portion, so that gas suction is stably and efficiently performed. In particular, the gas inflow pipe is located substantially in the center of the throttle part of the flow path, and allows the gas to flow in at a position where the liquid flow is stable upstream of the throttle part of a predetermined length, and further the liquid flow into which the gas has flowed is further introduced. It stabilizes by the throttle part downstream from the opening part of the gas inflow pipe, and stabilizes the inflow of gas.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the gas-liquid dissolution and mixing apparatus of the present invention will be described below with reference to the drawings. 1 and 2 show a first embodiment of the present invention. As shown in the figure, the gas-liquid dissolving and mixing apparatus of this embodiment is used in a liquid such as water in air, oxygen, ozone or other inert gas. A suction device 10 for mixing various gases, etc. is provided, and a leading end portion of the liquid pipe 12 is attached to an inflow portion 11 of the suction device 10. The outflow part 13 of the suction device 10 is connected to a gas-liquid mixing tank 14 as a mixing part for mixing the gas and liquid. A pipe line 16 is connected to the lower outlet 15. An outlet throttle 18 is provided at the distal end of the pipeline 16, and a short pipeline 20 is connected downstream of the outlet throttle 18.
[0013]
As shown in FIG. 2, a venturi-shaped flow path 24 is formed in the suction device 10. The throttle section 22, which is a throat section that gently narrows the flow path, is provided at the center. An expanding portion 26 is formed on the downstream side of the venturi-shaped channel 24. The constricted portion 22 is formed in a cylindrical shape, and the constricted portion 22 has a predetermined length of a parallel portion 28 having a substantially constant cross-sectional area in the liquid flow direction, and the gas inflow pipe 30 is located at a substantially central portion of the parallel portion 28. is doing.
[0014]
This gas inflow pipe 30 is arranged in the liquid flow direction in the flow path 24, and is bent at a right angle at the inflow portion 11 portion of the aspirator 10 and goes out to the outside. The gas inflow pipe 30 may be opened to the outside air when sucking air under atmospheric pressure, and connected to a cylinder or a compressor when a large amount of gas is sent under pressure. Is done.
[0015]
The distance from the inlet part 22a of the throttle part 22 of the suction device 10 to the opening part 30a of the gas inlet pipe 30 and the distance from the opening part 30a of the gas inlet pipe 30 to the outlet part 22b of the throttle part 22 are as follows. The diameter of each channel is 1.5 to 4 times, preferably 1.5 to 2 times considering the pipe resistance. The length of the parallel part 28 of the throttle part 22 is 3 to 8 times the diameter of the flow path of the throttle part 22, and is preferably 3 to 4 times considering the pipe resistance.
[0016]
The gas-liquid mixing tank 14 connected to the downstream side of the spreading part 26 is formed with a flow path 32 from which the liquid flows down from the top to the bottom. The flow path 32 is formed by partition walls 33 in which horizontal portions and vertical portions are alternately formed and form a horizontal portion. And the suction device 10 is connected to the inlet part 34 of the upper part of the flow path 32, and the pipe line 16 is connected to the lower outlet part 15 side. In the vicinity of the outlet portion 15 of the gas-liquid mixing tank 14, an excess gas separation portion 36 provided with a vertical branch channel for allowing excess gas to escape upward is formed, and above the excess gas separation portion 36, the excess gas separation portion 36 is provided. An opening 38 for releasing gas to the outside is provided.
[0017]
The operation of the gas-liquid dissolution and mixing apparatus of this embodiment will be described below. First, a liquid such as water that has flowed into the inflow portion 11 of the suction device 10 from the liquid pipe 12 is accelerated by the throttle portion 22 of the flow path 24, once the static pressure is reduced, and the flow velocity is reduced through the widened portion 26. Again, the static pressure increases. At this time, a gas such as air is sent from the opening 30 a of the gas inflow pipe 30 to the flow path 24. Here, the cross-sectional area S _A of the parallel portion 28 of the throttle portion 22 and the total cross-sectional area S _B of the outlet throttle 18 may satisfy the following expressions.
P _A <P _G (1)
P _G is a pressure of the gas flowing from the gas inlet tube 30.
P _A is given by the following equation (2) according to Bernoulli's theorem and continuity equation in hydrodynamics, and is a static pressure in the parallel portion 28 at a position where the opening 30 a of the gas inflow pipe 30 is located.
P _A = (1−S _B ² / S _A ² ) P ₁ + (δP + P _B ) S _B ² / S _A ² (2)
Here, P ₁ is the total pressure of the liquid flowing into the parallel portion 28, δP is the pressure loss from the parallel portion 28 to the outlet throttle 18, and P _B is the static pressure on the outlet side of the outlet throttle 18.
[0018]
Therefore, the gas is efficiently mixed and dissolved in the liquid by setting the pressure of the liquid, the size of the gas inlet pipe 30, the outlet throttle 18, etc. so as to satisfy the above formulas (1) and (2). The optimum conditions are obtained. Moreover, the gas-liquid mixing tank 14 is more preferable if the gas-liquid contact time is obtained under pressure until the gas dissolves in the liquid and becomes saturated. Since the gas-liquid contact time depends on the volume of the mixing section, it is preferable that the gas-liquid mixing tank 14 has a certain length. In addition, a predetermined pressure may be required for gas-liquid dissolution or gas-liquid reaction, and the outlet throttle 18 also has a function of keeping the inside of the gas-liquid mixing tank 14 at a predetermined pressure. The pressure inside the gas-liquid mixing tank 14 is expressed by the following formula (3) when the cross-sectional area of the gas-liquid mixing tank 14 is sufficiently wide.
_{^{P C = ρU 2/2 +}} P B + δP 2 (3)
Here, P _C the gas-liquid mixing tank 14 internal pressure, [rho is the density of the liquid, U is the flow velocity of the liquid at the outlet aperture 18, P _B is the outlet side of the static pressure at the outlet aperture 18, [delta] P ₂ is a gas-liquid This is the pressure loss from the mixing tank 14 to the outlet throttle 18.
[0019]
The gas sucked from the opening 30a of the gas inflow pipe 30 becomes bubbles and flows into the gas-liquid mixing tank 14 together with the liquid in the flow path 24, and the gas that has become bubbles has a static pressure in the gas-liquid mixing tank 14. Since it is higher than the throttle part 22, it dissolves in the liquid. Then, the static pressure is lowered again at the outlet throttle 18 from the gas-liquid mixing tank 14 through the pipe line 16, and the dissolved gas becomes fine bubbles and precipitates in the liquid. Further, the surplus gas is released to the outside through the opening 38 above the surplus gas separation unit 36. Furthermore, the bubbles that have not been completely dissolved are sheared finely at the outlet restrictor 18 and become microbubbles of several tens to several hundreds μm and dispersed in the liquid.
[0020]
According to the gas-liquid dissolution and mixing apparatus of this embodiment, the gas inflow pipe 30 is coaxially disposed at the center of the parallel portion 28 of the throttle section 22 of the suction device 10, and gas is efficiently and stably supplied from the gas inflow pipe 30. It can be aspirated and mixed into the liquid. In particular, since the opening 30a of the gas inflow pipe 30 is directed in the liquid flow direction and the gas is introduced in the liquid flow direction at the center of the liquid flow, gas suction can be stably and efficiently performed. In addition, the gas inflow pipe 30 is positioned substantially at the center of the throttle portion 22 of the flow path, the liquid flow is stabilized at the parallel portion 28 on the upstream side of the throttle portion 22, and the gas flows into the center portion of the stable liquid flow. The liquid flows in and is further stabilized by the parallel portion 28 downstream of the opening 30a of the gas inflow pipe 30 to further stabilize the gas inflow.
[0021]
Next, a second embodiment of the present invention will be described with reference to FIG. Here, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted. In the suction device 10 of this embodiment, the gas inflow pipe 30 is arranged linearly with respect to the suction device 10, and the suction device 10 is bent at a right angle at the inflow portion 11 of the flow path 24. The effect similar to the said embodiment can be acquired also by this embodiment.
[0022]
Next, a third embodiment of the present invention will be described with reference to FIG. Here, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted. The gas-liquid dissolution and mixing apparatus of this embodiment is provided with a pipe line 40 as a mixing unit for mixing gas and liquid instead of the gas-liquid mixing tank 14 of the first embodiment. According to this embodiment, the gas-liquid dissolution and mixing device can be configured simply by connecting the conduit 40 to the suction device 10 and attaching the outlet throttle 18 to the tip of the conduit 40, and the configuration is simple. Easy to assemble and handle.
[0023]
Next, a fourth embodiment of the present invention will be described with reference to FIG. Here, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted. In the gas-liquid dissolving and mixing apparatus of this embodiment, the pipe line 16 connected to the outlet portion 15 of the gas-liquid mixing tank 14 branches in the middle, and a plurality of branch pipe lines 42 are provided. The outlet throttles 18 are attached to the distal ends of the branch pipes 42, respectively, and the gas solution is discharged from the pipe 43 on the outlet side.
[0024]
Since the gas-liquid dissolution and mixing apparatus of this embodiment is branched into a plurality of pipelines, the gas solution can be supplied to different supply destinations and can be used for a wider range of applications.
[0025]
Next, a fifth embodiment of the present invention will be described with reference to FIG. Here, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted. In the gas-liquid dissolution and mixing apparatus of this embodiment, an outlet throttle 18 is provided in the pipeline 16 before branching in the fourth embodiment, and the gas-liquid mixed flow that has passed through the outlet throttle 18 is divided into a plurality of pipelines 44 at the branching portion. The gas-liquid mixed flow is supplied by dividing.
[0026]
Next, a sixth embodiment of the present invention will be described with reference to FIG. Here, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted. The gas-liquid dissolution and mixing apparatus of this embodiment includes a pump 52 that is a liquid pressure feeding unit via a liquid pipe 50 in the suction device 10 of the first embodiment. A water supply source 56 is connected to the upstream side of the pump 52 via a liquid pipe 54 so that the water to be treated 58 can be pumped to the aspirator 10.
[0027]
The gas inflow pipe 30 of the suction device 10 is connected to a compressor 62 via a gas pipe 60. The outflow part 13 of the aspirator 10 is connected to a gas-liquid mixing tank 14 which is a mixing part in which liquid flows in a stepwise manner from the top to the bottom, and a pipe line is connected to the outlet part 15 at the lower part of the gas-liquid mixing tank 14. 16 is connected. An outlet throttle 18 is provided at the distal end of the pipeline 16, and a pipeline 20 is connected downstream of the outlet throttle 18. A treated water tank 66 that accommodates the water to be treated 64 is provided at the tip of the pipe line 20.
[0028]
The aspirator 10 has the same configuration as that shown in FIG. An electromagnetic valve 70 is attached to the upper surface of the gas-liquid mixing tank 14, and a valve 72 is provided on the upper surface of the surplus gas separation unit 36. Further, sensors 73 and 74 for detecting the liquid level are provided on the side surface of the surplus gas separation unit 36 at the lower limit and the upper limit position of the liquid level.
[0029]
The operation of the gas-liquid dissolution and mixing apparatus of this embodiment will be described below. The treated water 58 stored in the water supply source 56 is pumped to the aspirator 10 by the pump 52 through the liquid pipes 54 and 50. In addition, when the predetermined pressure required for gas-liquid mixing is applied to the to-be-processed water 58 sent to the suction device 10, the pump 52 can also be abbreviate | omitted. In the suction device 10, the static pressure is accelerated by the throttle portion 22 of the flow path 24, temporarily decreases through the widened portion 26, and the static pressure increases again. The pressure of the liquid is reduced at the throttle portion 22, and thereby a gas such as air is sent from the opening 30 a of the gas inflow pipe 30 to the flow path 24. The gas is sent to the gas inflow pipe 30 by the compressor 62 through the gas pipe 60 at a predetermined pressure. Accordingly, the cross-sectional area of the parallel portion 28 of the throttle portion 22 and the total cross-sectional area of the outlet throttle 18 must satisfy the expressions (1) and (2) of the first embodiment. Note that the compressor 62 may be other gas pressure feeding means such as a cylinder.
[0030]
The gas sucked from the opening 30a of the gas inflow pipe 30 becomes bubbles and flows into the gas-liquid mixing tank 14 together with the liquid in the flow path 24, and the gas that has become bubbles has a static pressure in the gas-liquid mixing tank 14. Since it is higher than the throttle part 22, it dissolves in the liquid. Then, the static pressure is lowered again at the outlet throttle 18 from the gas-liquid mixing tank 14 through the pipe line 16, and the dissolved gas becomes fine bubbles and precipitates in the liquid. Furthermore, the gas that has not been completely dissolved is sheared finely at the outlet restrictor 18 and is dispersed into the liquid as microbubbles of several tens to several hundreds of micrometers. The outlet throttle 18 also has a function of maintaining the pressure inside the gas-liquid mixing tank 14. The condition is expressed by the above-described formula (3) when the cross-sectional area of the gas-liquid mixing tank 14 is sufficiently wide.
[0031]
Here, the electromagnetic valve 70 releases the electromagnetic valve 70 for at least 3 seconds when the pump 52 is stopped, and releases the pressure inside the gas-liquid mixing tank 14. The valve 72 is appropriately operated so that the liquid level is between the upper limit and the lower limit corresponding to the signals of the sensors 73 and 74, and the liquid is not mixed in the exhausted excess gas. In this operation, a means for displaying that the liquid level has reached the lower limit or the upper limit is provided by signals from the sensors 73 and 74, and the operator operates the valve 72 by the display, and signals from the sensors 73 and 74 are displayed. Therefore, the valve 72 may be automatically opened and closed, and the control method can be appropriately selected. Note that the sensors 73 and 74 and the operation means thereof may not be provided if the liquid in the exhaust does not matter, such as when some liquid is allowed to be exhausted.
[0032]
According to the gas-liquid dissolution and mixing apparatus of this embodiment, in addition to the effects of the first embodiment, a desired gas can be efficiently mixed and dissolved at a desired liquid pressure and pressure, and the treatment liquid with gas can be efficiently used. Can be manufactured well. According to this embodiment, the gas-liquid ratio was 400%, and gas-liquid mixing could be realized stably.
[0033]
Next, a seventh embodiment of the present invention will be described with reference to FIGS. Here, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted. In the gas-liquid dissolution and mixing apparatus of this embodiment, a plurality of gas-liquid mixing tanks 76 similar to the gas-liquid mixing tank 14 of the gas-liquid dissolution and mixing apparatus of the sixth embodiment are arranged, and the gas-liquid mixing flow is each gas-liquid mixing tank. 76 is passed through in series. Further, the surplus gas separation unit 78 is provided separately on the downstream side of the gas-liquid mixing tank 76. Each gas-liquid mixing tank 76 and the surplus gas separation unit 78 are connected by a pipe 80. The piping 80 is connected so as to connect the lowermost outlet portion 15 of the gas-liquid mixing tank 76 to the uppermost inlet portion 34 of the adjacent gas-liquid mixing tank 76. In this embodiment, three gas-liquid mixing tanks 76 are connected, but this number can be set as appropriate.
[0034]
The operation of the gas-liquid dissolution and mixing apparatus of this embodiment will be described below. The gas-liquid dissolution and mixing apparatus of this embodiment also has the same effect as the above-described embodiment, but by connecting a plurality of gas-liquid mixing tanks 76, the gas-liquid contact time can be increased and the gas-liquid ratio can be further increased. Can be bigger. Here, in order to increase the gas-liquid contact time, the number of stages of the gas-liquid mixing tank may be increased. However, if the number of stages is simply increased, the height of the gas-liquid mixing tank increases, and the liquid does not flow. It requires energy to be pumped up to the uppermost stage of the gas-liquid mixing tank, resulting in poor efficiency. Therefore, by arranging a plurality of gas-liquid mixing tanks 76, a small and efficient gas-liquid mixing tank can be obtained.
[0035]
Next, an eighth embodiment of the present invention will be described with reference to FIGS. Here, the same members as those of the above-described embodiment are denoted by the same reference numerals, and description thereof is omitted. In the gas-liquid dissolution and mixing apparatus of this embodiment, a plurality of gas-liquid mixing tanks 76 are arranged in the same manner as the gas-liquid dissolution and mixing apparatus of the seventh embodiment, so that gas and liquid pass through each gas-liquid mixing tank 76 in series. It is a thing. In the case of this embodiment, the gas and the liquid are respectively sent to the adjacent gas-liquid mixing tank 76 by separate gas pipes 82 and liquid pipes 84. Therefore, the gas pipe 82 is connected to the upper part 15 a of the lowermost outlet part 15 of the gas-liquid mixing tank 76 and connected to the upper part 34 a of the uppermost inlet part 34 of the adjacent gas-liquid mixing tank 76. Yes. Further, the liquid pipe 84 is connected to a lower part 15 b of the lowermost outlet part 15 of the gas-liquid mixing tank 76 and is connected to a lower part 34 b of the uppermost inlet part 34 of the adjacent gas-liquid mixing tank 76. The gas pipe 82 and the liquid pipe 84 mainly send gas and liquid. Usually, the liquid is mixed also in the gas sent through the gas pipe 82, and the gas is also mixed into the liquid sent through the liquid pipe 84. is doing.
[0036]
According to this embodiment, in addition to the same effects as those of the above-described embodiment, a gas having a low density is mainly sent to the adjacent gas-liquid mixing tank 76 by an upper gas pipe 82, and a liquid having a high density is mainly lower. The liquid pipes 84 are respectively transported separately. Thereby, each pipe line resistance is reduced and pumping efficiency improves.
[0037]
In addition, the mixing part of the gas-liquid dissolution mixing apparatus of this invention may use a fixed or flexible pipe line other than the said embodiment, and the shape of a gas-liquid mixing tank can also be set arbitrarily. Further, the shape of the outlet throttle may be a nozzle portion having one or a plurality of through holes in addition to the above embodiment. Further, the throttle portion may be one whose inner diameter changes stepwise. Further, the mixing section may be provided with an intermediate throttle having a larger cross-sectional area than the outlet throttle in the middle thereof. The parallel part of this throttle part should just be substantially parallel, and should just be a thing which stabilizes a flow.
[0038]
【The invention's effect】
The gas-liquid dissolving and mixing apparatus of the present invention can suck and mix gas in a liquid efficiently and stably by a simple apparatus. In particular, by providing a mixing portion that repeats slow and rapid, gas can be dissolved more efficiently and effectively, and waste of gas can be reduced.
[Brief description of the drawings]
FIG. 1 is a schematic view showing a first embodiment of a gas-liquid dissolution and mixing apparatus of the present invention.
FIG. 2 is a longitudinal sectional view of an aspirator of the gas-liquid dissolution and mixing apparatus according to the first embodiment.
FIG. 3 is a longitudinal sectional view of an aspirator of a gas-liquid dissolution and mixing apparatus according to a second embodiment of the present invention.
FIG. 4 is a schematic view showing a third embodiment of the gas-liquid dissolving and mixing apparatus of the present invention.
FIG. 5 is a schematic view showing a fourth embodiment of the gas-liquid dissolving and mixing apparatus of the present invention.
FIG. 6 is a schematic view showing a fifth embodiment of the gas-liquid dissolving and mixing apparatus of the present invention.
FIG. 7 is a schematic view showing a sixth embodiment of the gas-liquid dissolving and mixing apparatus of the present invention.
FIG. 8 is a schematic view showing a seventh embodiment of the gas-liquid dissolving and mixing apparatus of the present invention.
FIG. 9 is a sectional view of a gas / liquid mixing tank of a seventh embodiment of the gas / liquid dissolving / mixing apparatus of the present invention;
FIG. 10 is a cross-sectional view of a gas-liquid separation unit of a seventh embodiment of the gas-liquid dissolution and mixing apparatus of the present invention.
FIG. 11 is a schematic view showing an eighth embodiment of the gas-liquid dissolving and mixing apparatus of the present invention.
FIG. 12 is a sectional view of a gas / liquid mixing tank of an eighth embodiment of the gas / liquid dissolving / mixing apparatus of the present invention;
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Aspirator 12 Liquid piping 16, 20 Pipe line 14 Gas-liquid mixing tank 22 Restriction part 24 Flow path 26 Spreading part 28 Parallel part 30 Gas inflow pipe

Claims

A throttle part provided in the liquid flow path, a widened part that gradually expands the liquid flow path following the throttle part, and a gas inflow pipe that opens in the liquid flow direction in the throttle part, comprising a mixing unit for mixing the gas flowing from the liquid and the gas inlet pipe in provided the liquid flow path downstream of the expanded portion, and an aperture outlet provided on the outlet side of the mixing portion, the diaphragm A parallel portion having a substantially constant cross-sectional area in the flow direction of the liquid is provided at a predetermined length, and the gas inflow pipe is located in the parallel portion, on the upstream side of the throttle portion of the liquid channel, A liquid pumping means for pumping liquid via a liquid pipe is connected, and the mixing section is a gas-liquid dissolution mixing device in which the flow path is formed in a gradient that repeats gradually and gradually, and the fluid flows from top to bottom,
Regarding the flow path from the throttle part to the outlet throttle of the liquid channel, the cross-sectional area S _{A of the} parallel part of the throttle part, the total cross-sectional area S _{B of the} outlet throttle , and the pressure P _C inside the mixing part And the static pressure P _B on the outlet side of the outlet throttle satisfies the relationship of the following expressions (1), (2), and (3):
P _A <P _G (1)
P _A = (1−S _B ² / S _A ² ) P ₁ + (δP + P _B ) S _B ² / S _A ² (2)
_{^{P C = ρU 2/2 +}} P B + δP 2 (3)
P _A : Bernoulli's theorem on fluid dynamics and the continuity formula, the static pressure of the parallel portion at the position of the opening of the gas inflow pipe given by Formula (2), P _G : from the gas inflow pipe Inflowing gas pressure, P ₁ : total pressure of liquid flowing into the parallel part, δP: pressure loss from the parallel part to the outlet throttle, ρ: density of the liquid, U: the above in the outlet throttle Liquid flow rate, δP ₂ : pressure loss from the mixing section to the outlet throttle,
A gas-liquid dissolving and mixing apparatus characterized by the above .

The gas inflow pipe is disposed in the liquid flow direction of the throttle section, and the distance from the inlet section of the throttle section to the opening section of the gas inflow pipe, and from the opening section of the gas inflow pipe to the outlet section of the throttle section. The gas-liquid dissolving and mixing apparatus according to claim 1, wherein each of the distances is 1.5 to 4 times the diameter of the throttle portion.

The gas-liquid dissolution and mixing apparatus according to claim 2, wherein the length of the parallel portion of the throttle portion is 3 to 8 times the diameter of the throttle portion.

The gas-liquid dissolution and mixing apparatus according to claim 1, 2 or 3, wherein a gas pumping means is connected to the upstream side of the gas inflow pipe through a gas pipe.

The gas-liquid dissolving and mixing apparatus according to any one of claims 1 to 4, wherein an intermediate throttle having a larger cross-sectional area than the outlet throttle is provided in the middle of the mixing section.

The gas-liquid dissolution and mixing apparatus according to any one of claims 1 to 5, wherein the mixing section is provided with a branch channel protruding upward to allow excess gas to escape to the outside.

The gas-liquid dissolution according to any one of claims 1 to 6, wherein a branch flow path is provided downstream of the mixing section, and the outlet throttle is provided in a flow path before or after branching of the branch flow path. Mixing equipment.

The gas-liquid dissolution and mixing apparatus according to any one of claims 1 to 6, wherein a plurality of the mixing units are connected in series in a liquid flow direction.

9. The gas mixing unit according to claim 8, wherein a plurality of the mixing units are connected in series in a liquid flow direction, and the mixing units are separately connected by a gas pipe that mainly sends gas and a liquid pipe that mainly sends liquid. Liquid dissolution mixing device.

The gas-liquid dissolution and mixing apparatus according to any one of claims 1 to 9, wherein a valve is provided on at least one uppermost stage of the mixing section, and means for releasing the valve for at least 3 seconds when the liquid pumping means is stopped.