JP4616953B2

JP4616953B2 - Transport container pressure drop system and gas blowing device for storage tank

Info

Publication number: JP4616953B2
Application number: JP33854699A
Authority: JP
Inventors: 善明中迫; 健一川岸; 誠尾崎; 克夫小菅
Original assignee: IHI Plant Construction Co Ltd; Hiroshima Gas Co Ltd
Current assignee: IHI Plant Construction Co Ltd; Hiroshima Gas Co Ltd
Priority date: 1999-11-29
Filing date: 1999-11-29
Publication date: 2011-01-19
Anticipated expiration: 2019-11-29
Also published as: JP2001153297A

Description

【０００１】
【発明の属する技術分野】
本発明は、輸送容器内等を落圧すべく輸送容器からのガスを貯蔵タンクの液中に吹き込んで吸収させるための輸送容器の落圧システム及び貯蔵タンクへのガス吹き込み装置に関するものである。
【０００２】
【従来の技術】
従来、ＬＮＧサテライト基地、液体空気貯蔵設備、ＬＰＧ貯蔵設備、液体アンモニア貯蔵設備等に設置されている貯蔵タンクにおいて、貯蔵液の受け入れは、タンクローリ或いは他の輸送容器に積載された液を荷卸している。
【０００３】
タンクローリ或いは他の輸送容器からの荷卸しを行う一般的な荷卸し方法は、受け入れ側の貯蔵タンク内を落圧し、その落圧したときのガス或いはタンクローリや輸送容器内を積載液と同種のガスで加圧し、その差圧を利用して輸送容器内の積載液を受け入れ側の貯蔵タンクに送液するようにしている。
【０００４】
この荷卸し終了後は、輸送容器の返送途中の安全性確保のために、輸送容器内の圧力を低くすることが必要である。
【０００５】
落圧操作で排出されるガスは受け入れ側貯蔵タンクに戻されるのが一般的であるが、ガスを貯蔵タンクのガス相に戻すと、貯蔵タンク内圧力が高くなって、輸送容器内の落圧を十分に行うことはできない。
【０００６】
これを解決するために受け入れ側貯蔵タンクの下部の液中にガス注入して液に吸収させて受け入れ側タンクの圧力上昇を防止して落圧することがなされている。
【０００７】
ガスの注入は、注入ノズルの先端に邪魔板を設置してガスを分散するか或いはリング状の管に放散孔を設けてタンク下部に設置し、ガスを分散して液に吸収させる等の方法で行っている。
【０００８】
【発明が解決しようとする課題】
しかしながら、前者の場合、ノズルから注入される泡径が大きいためガス吸収が十分に行えない問題がある。すなわち、常温の水に沸騰した水蒸気を吹き込むように、液温が上記の凝縮温度より十分に低い場合は、温度差が大きく伝熱量も大きいので泡径が大きくても液への吸収も容易であるが、ガスの凝縮温度に対してタンク内液の過冷却度が小さい場合は、温度差が小さく伝熱量が小さくなるので液への吸収が十分に行えない。この場合、タンク内液面が高ければ、その液位でガスを吸収することも可能であるが、低い液面の場合には、ガスが吸収されないおそれがある。その結果、輸送容器内圧力を下げることができない。
【０００９】
また後者の場合、放散孔の孔径を小さくすることで、吹き出されるガスの泡径を小さくして伝熱速度を大きくすることができるが、相対的に放散孔全体の開口面積が小さくなり、輸送容器内の落圧に時間が掛かる問題がある。すなわち、ローリ等の輸送容器の落圧は短時間に行う必要があるが、ガス吸収を考慮して孔径を小さくすると、単位時間当たり液に吹き込むガス流量を少なくする必要があり、このため落圧を短時間で行うことができない問題がある。また、放散孔の孔径が小さくてもリング径を大きくして、放散孔の数を増やし全体の開口面積を大きくすれば、短時間の落圧は可能となるが、輸送容器で落圧するためのガス量は、一定でなく、設定より大量のガスを処理する場合には時間がより多く掛かることになり、また設定よりガス量が少ない場合には、リングの一部の放散孔からガスが吹き込まれることとなり、ガスがタンク内で偏って放出されるため、ガスの分散性が悪くなり、十分に液の過冷却熱が利用されない問題が発生する。またタンク底部に不当に大型の構造物を設置することになり経済的でない。
【００１０】
そこで、本発明の目的は、上記課題を解決し、輸送容器のガスを、貯蔵タンクの液位やガス量の変動にかかわらず吹き込んで液中に吸収させることが可能な輸送容器の落圧システム及び貯蔵タンクへのガス吹き込み装置を提供することにある。
【００１１】
【課題を解決するための手段】
上記目的を達成するために、請求項１の発明は、輸送容器内の積載液を貯蔵タンクに荷卸しする際に、受け入れる貯蔵タンク或いは他の貯蔵タンクの貯液を気化させてガス化し、そのガスを輸送容器内に導入して輸送容器内の圧力を高くし、その輸送容器と受け入れる貯蔵タンクの圧力差を利用して輸送容器内の積載液を貯蔵タンクに送液し、送液完了後に、上記輸送容器内の高圧のガスを落圧ラインから受け入れる貯蔵タンク或いは他の貯蔵タンクの液中にノズルを介して吹き込んで上記輸送容器内を落圧するシステムにおいて、貯蔵タンク内の下部に設けた上記ノズルの上方にノズル径より大きな径のガス分散板を設け、そのガス分散板と上記ノズルの上部を包囲する下端が開口したキャップを設け、かつそのキャップを、上部シールプレートと上部シールプレートに取り付けた下端が拡径したスカートで形成し、上記ノズルから吹き込む輸送容器内の高圧のガスをキャップ内のガス分散板に当てると共に分散させてキャップ内に吹き込み、そのキャップ内で、吹き込んだガスを貯蔵タンクの液位に応じた圧力にし、そのキャップ内のガスをキャップの上部シールプレートとスカートに形成した多数の放散孔から貯蔵タンク内の貯液中に放出して上記ガスを貯液に吸収させるようにした輸送容器の落圧システムである。
【００１２】
請求項２の発明は、請求項１記載の輸送容器の落圧システムに用いる、上記輸送容器からの高圧のガスを、ノズルを介して受け入れる貯蔵タンク或いは他の貯蔵タンクの液中に吹き込んで上記輸送容器内を落圧するための貯蔵タンクへのガス吹き込み装置において、貯蔵タンクの下部に設けた上記ノズルの上方にノズル径より大きな径のガス分散板を設け、そのガス分散板と上記ノズルの上部を包囲する下端が開口したキャップを設け、かつそのキャップを、上部シールプレートと上部シールプレートに取り付けた下端が拡径したスカートで形成し、そのキャップの上部シールプレートとスカートに多数の放散孔を設けた貯蔵タンクへのガス吹き込み装置である。
【００１３】
請求項３の発明は、キャップは、上部シールプレートと下端が拡径されたスカートとで円錐状乃至角錐状に形成され、そのスカートがノズルサポートを介してノズルに支持され、上部シールプレートに孔径５〜１０ｍｍの放散孔が形成され、スカートに孔径５〜１５ｍｍの放散孔が多数形成された請求項２記載の貯蔵タンクへのガス吹き込み装置である。
【００１５】
請求項４の発明は、キャップの下方には、キャップの下端開口径より十分大きな径の邪魔板が設けられる請求項２又は３記載の貯蔵タンクへのガス吹き込み装置である。
【００１６】
請求項５の発明は、キャップの下縁を、円周方向に沿って複数の三角形状の切り込みを形成した形状乃至鋸歯状に形成した請求項２〜４いずれかに記載の貯蔵タンクへのガス吹き込み装置である。
【００１７】
【発明の実施の形態】
以下、本発明の好適一実施の形態を添付図面に基づいて詳述する。
【００１８】
図１は、本発明が適用されるＬＮＧサテライト基地にタンクローリや輸送容器で、ＬＮＧを荷卸ししたり、輸送容器内を落圧する状態を示している。
【００１９】
図１において、ＬＮＧサテライト基地は、ＬＮＧを貯蔵する二重殻タンクで構成される複数の貯蔵タンク１０，１０からなり、その貯蔵タンク１０，１０の上下に、送液ライン１１，１２が接続され、その送液ライン１１，１２の上流側が合流されると共に、タンクローリや輸送容器１３内の積載液１４を受け入れる受入ライン１５に接続される。この上下の送液ライン１１，１２には、それぞれ開閉弁１６，１７が接続されると共に受入ライン１５には受入弁１８が接続される。
【００２０】
この受入弁１８と輸送容器１３の液側開閉弁２０とがローディングアーム（或いはサテライト基地によってはフレキシブルホース）２１で接続されるようになている。
【００２１】
輸送容器１３には、ガス側開閉弁２２が設けられており、貯蔵タンク１０の貯液２４を気化器２５で気化し、ガス側開閉弁２２を介して輸送容器１３内の上部に供給できるようになっている。
【００２２】
すなわち、例えば、積載液１４を受け入れている貯蔵タンク１０内の貯液２４を抜き出しライン２６、開閉弁２７、ポンプ２８を介して気化器２５に、或いは他の貯蔵タンク１０の貯液２４を、その液位により、抜き出しライン２９、開閉弁３０を介し気化器２５に供給され、その気化器２５でガス化されたガスが、気化器２５よりガスライン３１、開閉弁３２、ガス弁３３からローディングアーム（或いはフレキシブルホース）３４を通し、ガス側開閉弁２２を介して輸送容器１３内の上部に供給できるようになっている。
【００２３】
このガスライン３１のガス弁３３と開閉弁３２間には、ガスライン３１から分岐して落圧ライン３６が接続され、その落圧ライン３６が、開閉弁３７，３８を介して貯蔵タンク１０，１０内に設けたガス吹き込み装置４０に接続されるようになっている。
【００２４】
図１において、図示の実線で示した貯蔵タンク１０に輸送容器１３内の積載液１４を荷卸しする際には、輸送容器１３の液側開閉弁２０を、受入弁１８に接続されたローディングアーム２１と接続し、ガス側開閉弁２２を、ガス側開閉弁３３に接続されたローディングアーム３４と接続し、その状態で、受け入れる貯蔵タンク１０或いは他の貯蔵タンク１０の貯液２４を抜き出しライン２６又は２９を介して気化器２５に導入し、そこでガス化し、ガスライン３１を介し、ローディングアーム３４からガス側開閉弁２２を介して輸送容器１３内に導入して輸送容器１３内の圧力を高くすることにより、輸送容器１３内の積載液１４は、圧力差で、液側開閉弁２０、ローディングアーム２１から受入ライン１５を通して上部の送液ライン１１、開閉弁１６を介して貯蔵タンク１０の上部から送液される。
【００２５】
この場合、貯蔵タンク１０の上部のガス相は冷却されて貯蔵タンク１０内の圧力も同時に下がるが、貯蔵タンク１０内の圧力を下げる必要がない場合には、上部の送液ライン１１の開閉弁１６を閉じ、下部の送液ライン１２の開閉弁１７を開いて下部の送液ライン１２から積載液１４を送液するようにしてもよい。
【００２６】
輸送容器１３内の積載液１４の送液が完了すると輸送容器１３内は、気化器２５からのガスが充満されて約０．５〜０．６ＭＰａの圧力となる。
【００２７】
本発明においては、この輸送容器１３内のガスをガス側開閉弁２２から落圧ライン３６を介して受入側の貯蔵タンク１０の底部に設けたガス吹き込み装置４０或いは他の貯蔵タンク１０の底部に設けたガス吹き込み装置４０にてガスを貯液２４中に放出して吸収させるようにしたものである。
【００２８】
このガス吹き込み装置４０を図２により詳しく説明する。
【００２９】
図２において、貯蔵タンク１０の内槽底部の鏡板４１には、図１で説明した落圧ライン３６に接続されたノズル４２が、保護筒４３を介して垂直に取り付けられ、その貯蔵タンク１０内のノズル４２の外周が、ノズルサポート４４にて鏡板４１に起立するように支持される。
【００３０】
このノズル４２の上端の吹き込み口４２ａ上には、支持板４５を介してガス分散板４６が設けられると共に、ノズル４２の上部を包囲するように下端が開口した円錐台状のキャップ４８が設けられる。
【００３１】
このキャップ４８は、上面となる上部シールプレート４９と周面となるスカート５０からなり、そのスカート５０が、ノズルサポート５１を介してノズル４２に支持される。
【００３２】
スカート５０は、上部から下部にかけて末広がり状に形成され、その傾斜角は、鉛直線に対して１５〜４５度傾斜する円錐台状、角錐台状乃至梯型状に形成され、その下縁部５２は、円周方向に沿って複数の三角形状の切り込みを形成した形状乃至鋸歯状に形成される。
【００３３】
このキャップ４８の上部シールプレート４９には、孔径５〜１０mmφ程度の放散孔５３が設けられ、またスカート５０には、孔径５〜１５mmφ程度の放散孔５４が上下二段で横方向と縦方向に５０mm以上の間隔を置いて、更に上下の放散孔５４が上下で重ならないように千鳥状に形成される。
【００３４】
キャップ４８の下方には、キャップ４８の下端の径より十分大きな径の邪魔板５５が、キャップ４８下端より数センチ離れてノズル４２に取り付けられる。
【００３５】
このキャップ４８は、ノズル４２から吹き出されたガスが、貯液の液位に応じた圧力となり、その状態で、放散孔５３，５４から貯液内にガス噴射しつつ、ガスがキャップ４８内に充満して下縁５２まで、ガス室を形成するように放散孔５３，５４の全開孔径が設定される。
【００３６】
次に本発明の作用を述べる。
【００３７】
上述したように輸送容器１３を落圧する際、輸送容器１３内のガスは、落圧ライン３６を介し、ノズル４２の吹き込み口４２ａから、ガス分散板４６に当たって分散されてキャップ４８内に吹き出される。キャップ４８は下端が開口しておりキャップ４８内に吹き出されたガスは、ノズル４２から吹き出されるガス量の大小にかかわらず液圧に応じた圧力となり、またそのガス流量変化をキャップ４８の容量で吸収し、常に一定の条件でキャップ４８の放散孔５３，５４から貯液中に吹き出されると共に貯液に冷却されて液化して吸収される。
【００３８】
この際、ガス流量が大のときは、ガスは、キャップ４８の下縁５２からも吹き出されるが、下縁５２が鋸歯状に形成されるため、吹き出しガスは細かい泡となって液中に吹き出され、またガス量が少なくなったときは、順次キャップ４８内の液面は上がるが、キャップ４８内のガス圧が液位により一定のため同じ条件で放散孔５３，５４から放出されることとなる。また放散孔５４はスカート５０上に上下に千鳥状の形状であけられているので、吹き出しガスの泡が凝集することがない。
【００３９】
このキャップ４８からガスが吹き出される際、その上昇流でキャップ４８の下方からキャップ４８内に貯液が流れ込む巻き込み流が生じるが邪魔板５５にて、その貯液の巻き込みを阻止できると共にキャップ４８の下端乃至キャップ４８内に形成される液面が乱されることがなく、液の侵入によりキャップ４８と邪魔板５５間から、泡径の大きなガスが放出されることが防止される。また、タンク底部への泡の拡散も防止できる。
【００４０】
このように本発明においては、ノズル４２に下端が開口したキャップ４８を設けることで、キャップ４８内に吹き出されたガスは貯蔵タンク１０の液柱圧に応じた圧力となるため、輸送容器１３の圧力が暫減しても常時一定の条件でガスを液中に放出することが可能となり、輸送容器１３のガスを、貯蔵タンク１０の液柱圧と同じ圧力になるまで貯蔵液中に放出させることで、輸送容器１３を短時間で落圧させることが可能となる。
【００４１】
なお、輸送容器１３のガスは、荷卸し直後は、輸送容器１３内の圧力は約０．５〜０．６ＭＰａであり、貯蔵タンク１０内の液柱圧より十分に高く、キャップ４８と邪魔板５５間からガスが吹き出す場合には、輸送容器１３のガス側開閉弁２２の開度を調整して、落圧ライン３６に流すガス量を調整し、輸送容器１３の圧力がある程度下がったならば、ガス側開閉弁２２を全開として、輸送容器１３の圧力と貯蔵タンク１０の液柱圧差でガスを放出するようにする。
【００４２】
図１の実施の形態では、ガス吹き込み装置４０を吹き込み専用の落圧ライン３６のノズル４２に取り付けているが、複数の輸送容器から同時に受入を行わない設備では、液受入ラインのノズルに取り付け、その液受入ラインを用いて輸送容器の落圧も可能である。ガス吹き込み装置４０の適用は輸送容器の落圧だけでなく、隣接する貯蔵タンク内のガス相のガス圧が高い時に、そのガスを他の貯蔵タンクにガス吹き込み装置４０を介して吹き込んで落圧するシステムにも適用できることは勿論である。
【００４３】
【発明の効果】
以上要するに本発明によれば、輸送容器内の積載液を貯蔵タンクに荷卸し後に気化ガスで高圧となった輸送容器内を落圧させるに際して、ノズルに下端が拡径して開口したキャップを設け、ノズルからのガスをそのキャップ内のガス分散板に当てて分散させ、そのガスをキャップに設けた放散孔からガスを貯液中に放出するようにしたので、貯蔵タンクの液位やガス量の変動にかかわらず常に一定の条件で、液中に均一にガスを吹き込んで吸収させることができる。
【図面の簡単な説明】
【図１】本発明の一実施の形態を示す全体図である。
【図２】図１における本発明のガス吹き込み装置の詳細図である。
【符号の説明】
１０貯蔵タンク
１３輸送容器
３６落圧ライン
４２ノズル
４６ガス分散板
４８キャップ
５２下縁
５３，５４放散孔
５５邪魔板[0001]
BACKGROUND OF THE INVENTION
The present invention relates to gas injectors to落圧system and storage tank transportation container for absorbing by blowing in order to落圧the like shipping container transport container or these gases in a liquid storage tank is there.
[0002]
[Prior art]
Conventionally, in storage tanks installed in LNG satellite bases, liquid air storage facilities, LPG storage facilities, liquid ammonia storage facilities, etc., storage liquids can be received by unloading liquids loaded in tank trucks or other transport containers. Yes.
[0003]
A general unloading method for unloading from a tank truck or other transport container is to reduce the pressure in the storage tank on the receiving side, or the same type of gas as the liquid loaded in the tank truck or transport container. And using the differential pressure, the loading liquid in the transport container is sent to the storage tank on the receiving side.
[0004]
After unloading, it is necessary to reduce the pressure in the transport container in order to ensure safety during the return of the transport container.
[0005]
Generally, the gas discharged by the pressure drop operation is returned to the receiving storage tank. However, when the gas is returned to the gas phase of the storage tank, the pressure in the storage tank increases and the pressure drop in the transport container Can not do enough.
[0006]
In order to solve this problem, gas is injected into the liquid in the lower part of the receiving side storage tank and absorbed in the liquid to prevent the pressure in the receiving side tank from increasing and to reduce the pressure.
[0007]
For gas injection, a baffle plate is installed at the tip of the injection nozzle to disperse the gas, or a diffusion hole is provided in the ring-shaped tube and installed at the bottom of the tank to disperse the gas and absorb it into the liquid. Is going on.
[0008]
[Problems to be solved by the invention]
However, in the former case, since the bubble diameter injected from the nozzle is large, there is a problem that gas cannot be sufficiently absorbed. That is, when the liquid temperature is sufficiently lower than the above condensation temperature so that boiled water vapor is blown into normal temperature water, the temperature difference is large and the amount of heat transfer is large, so even if the bubble diameter is large, absorption into the liquid is easy. However, when the degree of supercooling of the liquid in the tank is small with respect to the gas condensation temperature, the temperature difference is small and the amount of heat transfer is small, so that the liquid cannot be sufficiently absorbed. In this case, if the liquid level in the tank is high, it is possible to absorb the gas at the liquid level, but if the liquid level is low, the gas may not be absorbed. As a result, the transport container pressure cannot be lowered.
[0009]
In the latter case, by reducing the hole diameter of the diffusion hole, it is possible to reduce the bubble diameter of the blown gas and increase the heat transfer rate, but the opening area of the entire diffusion hole is relatively reduced, There is a problem that the pressure drop in the transport container takes time. That is, it is necessary to reduce the pressure of a transport container such as a lorry in a short time, but if the hole diameter is reduced in consideration of gas absorption, it is necessary to reduce the gas flow rate blown into the liquid per unit time. There is a problem that cannot be performed in a short time. Moreover, even if the hole diameter of the diffusion hole is small, if the ring diameter is increased, the number of the diffusion holes is increased and the entire opening area is increased, the pressure can be reduced for a short time. The amount of gas is not constant, and it takes more time to process a larger amount of gas than the setting, and when the amount of gas is less than the setting, the gas is blown from a part of the discharge holes of the ring. As a result, the gas is discharged unevenly in the tank, so that the dispersibility of the gas is deteriorated, and the problem that the subcooling heat of the liquid is not sufficiently utilized occurs. In addition, an unnecessarily large structure is installed at the bottom of the tank, which is not economical.
[0010]
An object of the present invention, the above problems were solved, the transport container of gas, liquid level and the amount of gas blown in transport containers which can be absorbed in the liquid regardless of the fluctuations in the storage tank落圧The object is to provide a gas blowing device for the system and storage tank.
[0011]
[Means for Solving the Problems]
In order to achieve the above object, the invention of claim 1 is characterized in that when unloading the loaded liquid in the transport container to the storage tank, the liquid stored in the storage tank or other storage tank to be received is vaporized and gasified. Gas is introduced into the transport container to increase the pressure in the transport container, and the loaded liquid in the transport container is sent to the storage tank using the pressure difference between the transport container and the receiving storage tank. In the system in which the high pressure gas in the transport container is blown through the nozzle into the liquid of the storage tank or other storage tank that receives the pressure from the pressure drop line, the pressure in the transport container is reduced, and the system is provided at the lower part of the storage tank. A gas dispersion plate having a diameter larger than the nozzle diameter is provided above the nozzle, a cap having an open lower end surrounding the gas dispersion plate and the upper portion of the nozzle is provided, and the cap is attached to the upper seal plate. Formed with skirt lower end attached to the over preparative upper seal plate is expanded, blown into the cap by dispersing with shed high-pressure gas in the transport container blown from the nozzle to the gas distribution plate in the cap, the cap The gas blown into the storage tank is made to have a pressure corresponding to the liquid level of the storage tank, and the gas in the cap is discharged into the liquid storage in the storage tank through the numerous discharge holes formed in the upper seal plate and skirt of the cap. It is the pressure reduction system of the transport container which made the said liquid absorb a gas.
[0012]
According to a second aspect of the present invention, the high pressure gas from the transport container used in the pressure reducing system for the transport container according to the first aspect is blown into a liquid in a storage tank or another storage tank that receives the gas through a nozzle. In a gas blowing device into a storage tank for reducing the pressure in a transport container, a gas dispersion plate having a diameter larger than the nozzle diameter is provided above the nozzle provided at the lower portion of the storage tank, and the gas dispersion plate and the upper portion of the nozzle the cap lower end surrounding has opened is provided, and the cap, the top seal plate and the lower end attached to the upper seal plate formed of enlarged diameter and skirt, a large number of diffusion hole to the upper sealing plate and the skirt of the cap It is the gas blowing apparatus to the provided storage tank.
[0013]
According to a third aspect of the present invention, the cap is formed in a conical shape or a pyramid shape by an upper seal plate and a skirt having an enlarged lower end, and the skirt is supported by the nozzle through a nozzle support, and the hole diameter is formed in the upper seal plate. 3. A gas blowing device for a storage tank according to claim 2, wherein a diffusion hole having a diameter of 5 to 10 mm is formed and a number of diffusion holes having a diameter of 5 to 15 mm are formed in the skirt .
[0015]
According to a fourth aspect of the present invention, there is provided the gas blowing device for a storage tank according to the second or third aspect, wherein a baffle plate having a diameter sufficiently larger than a lower end opening diameter of the cap is provided below the cap.
[0016]
The invention according to claim 5 is the gas to the storage tank according to any one of claims 2 to 4 , wherein the lower edge of the cap is formed in a shape or a sawtooth shape in which a plurality of triangular cuts are formed along the circumferential direction. A blowing device.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.
[0018]
FIG. 1 shows a state where LNG is unloaded with a tank truck or a transport container at an LNG satellite base to which the present invention is applied or the inside of the transport container is dropped.
[0019]
In FIG. 1, the LNG satellite base is composed of a plurality of storage tanks 10, 10 composed of double shell tanks for storing LNG, and liquid feed lines 11, 12 are connected to the upper and lower sides of the storage tanks 10, 10. The upstream sides of the liquid feeding lines 11 and 12 are joined together, and are connected to a receiving line 15 for receiving the tank 14 and the loaded liquid 14 in the transport container 13. Opening / closing valves 16 and 17 are connected to the upper and lower liquid feed lines 11 and 12, respectively, and a receiving valve 18 is connected to the receiving line 15.
[0020]
The receiving valve 18 and the liquid side opening / closing valve 20 of the transport container 13 are connected by a loading arm 21 (or a flexible hose depending on the satellite base).
[0021]
The transport container 13 is provided with a gas-side on-off valve 22 so that the liquid 24 in the storage tank 10 can be vaporized by the vaporizer 25 and supplied to the upper part of the transport container 13 via the gas-side on-off valve 22. It has become.
[0022]
That is, for example, the liquid storage 24 in the storage tank 10 that receives the loaded liquid 14 is withdrawn to the vaporizer 25 via the line 26, the on-off valve 27, and the pump 28, or the liquid storage 24 in another storage tank 10. Depending on the liquid level, the gas is supplied to the vaporizer 25 via the extraction line 29 and the open / close valve 30, and the gasified by the vaporizer 25 is loaded from the gas line 31, the open / close valve 32, and the gas valve 33 from the vaporizer 25. The arm (or flexible hose) 34 can be passed through the gas side opening / closing valve 22 and supplied to the upper part in the transport container 13.
[0023]
A gas pressure line 36 is branched from the gas line 31 between the gas valve 33 and the on-off valve 32 of the gas line 31 and connected to the storage tank 10, via the on-off valves 37, 38. 10 is connected to a gas blowing device 40 provided in the inside.
[0024]
In FIG. 1, when unloading the loaded liquid 14 in the transport container 13 to the storage tank 10 indicated by the solid line in the figure, the liquid side on-off valve 20 of the transport container 13 is connected to the loading arm 18 connected to the receiving valve 18. 21, the gas side on-off valve 22 is connected to a loading arm 34 connected to the gas side on-off valve 33, and in this state, the storage tank 10 to be received or the liquid storage 24 of the other storage tank 10 is drawn out. Alternatively, the gas is introduced into the vaporizer 25 via 29, gasified there, and introduced into the transport container 13 from the loading arm 34 via the gas side opening / closing valve 22 via the gas line 31 to increase the pressure in the transport container 13. As a result, the loading liquid 14 in the transport container 13 is caused by a pressure difference, the liquid side opening / closing valve 20, the loading arm 21 through the receiving line 15, the upper liquid feeding line 11, It is fed from the top of the storage tank 10 via the valve closing 16.
[0025]
In this case, the gas phase in the upper part of the storage tank 10 is cooled and the pressure in the storage tank 10 is lowered at the same time. However, when there is no need to reduce the pressure in the storage tank 10, the on-off valve of the upper liquid feed line 11 is used. 16 may be closed and the on-off valve 17 of the lower liquid supply line 12 may be opened to supply the loaded liquid 14 from the lower liquid supply line 12.
[0026]
When the transport of the loaded liquid 14 in the transport container 13 is completed, the transport container 13 is filled with the gas from the vaporizer 25 and becomes a pressure of about 0.5 to 0.6 MPa.
[0027]
In the present invention, the gas in the transport container 13 is supplied from the gas side opening / closing valve 22 to the bottom of the storage tank 10 on the receiving side via the pressure drop line 36 or the bottom of the other storage tank 10. The gas is discharged into the liquid storage 24 by the gas blowing device 40 provided and absorbed.
[0028]
The gas blowing device 40 will be described in detail with reference to FIG.
[0029]
In FIG. 2, a nozzle 42 connected to the pressure drop line 36 described in FIG. 1 is vertically attached to the end plate 41 at the bottom of the inner tank of the storage tank 10 through a protective cylinder 43. The outer periphery of the nozzle 42 is supported by the nozzle support 44 so as to stand on the end plate 41.
[0030]
A gas dispersion plate 46 is provided on the blowing port 42 a at the upper end of the nozzle 42 via a support plate 45, and a truncated cone-shaped cap 48 having a lower end opened so as to surround the upper portion of the nozzle 42. .
[0031]
The cap 48 includes an upper seal plate 49 as an upper surface and a skirt 50 as a peripheral surface, and the skirt 50 is supported by the nozzle 42 via a nozzle support 51.
[0032]
The skirt 50 is formed in a divergent shape from the upper part to the lower part, and the inclination angle thereof is formed in a truncated cone shape, a truncated pyramid shape or a trapezoidal shape inclined by 15 to 45 degrees with respect to the vertical line, and a lower edge portion 52 thereof. Is formed in a shape or a sawtooth shape in which a plurality of triangular cuts are formed along the circumferential direction .
[0033]
The upper seal plate 49 of the cap 48 is provided with a diffusion hole 53 having a hole diameter of about 5 to 10 mmφ, and the skirt 50 is provided with a diffusion hole 54 having a hole diameter of about 5 to 15 mmφ in the upper and lower stages in the horizontal and vertical directions. At intervals of 50 mm or more, the upper and lower diffusion holes 54 are formed in a staggered pattern so as not to overlap each other.
[0034]
Below the cap 48, a baffle plate 55 having a diameter sufficiently larger than the diameter of the lower end of the cap 48 is attached to the nozzle 42 a few centimeters away from the lower end of the cap 48.
[0035]
In this cap 48, the gas blown out from the nozzle 42 becomes a pressure corresponding to the liquid level of the liquid storage, and in this state, the gas is injected into the liquid storage through the diffusion holes 53, 54, and the gas enters the cap 48. The full opening diameters of the diffusion holes 53 and 54 are set so as to fill and form the gas chamber up to the lower edge 52.
[0036]
Next, the operation of the present invention will be described.
[0037]
As described above, when the transport container 13 is depressurized, the gas in the transport container 13 is dispersed from the blowing port 42a of the nozzle 42 against the gas dispersion plate 46 and blown into the cap 48 via the depressurization line 36. . The cap 48 has an opening at the lower end, and the gas blown into the cap 48 has a pressure corresponding to the hydraulic pressure regardless of the amount of gas blown from the nozzle 42, and the change in gas flow rate is determined by the capacity of the cap 48. The liquid is always blown into the liquid storage from the diffusion holes 53 and 54 of the cap 48 under constant conditions, and is cooled to the liquid storage and liquefied and absorbed.
[0038]
At this time, when the gas flow rate is large, the gas is also blown out from the lower edge 52 of the cap 48. However, since the lower edge 52 is formed in a sawtooth shape, the blown-out gas becomes fine bubbles in the liquid. When the gas is blown out and the amount of gas is reduced, the liquid level in the cap 48 sequentially rises, but since the gas pressure in the cap 48 is constant depending on the liquid level, it is discharged from the diffusion holes 53 and 54 under the same conditions. It becomes. Further, since the diffusion holes 54 are formed in a zigzag shape on the top and bottom of the skirt 50, bubbles of the blowing gas do not aggregate.
[0039]
When the gas is blown out from the cap 48, the upward flow causes a entangled flow in which the stored liquid flows into the cap 48 from below the cap 48, but the baffle plate 55 can prevent the stored liquid from being entrained and the cap 48. The liquid surface formed in the lower end or the cap 48 is not disturbed, and the gas having a large bubble diameter is prevented from being released from between the cap 48 and the baffle plate 55 due to the penetration of the liquid. In addition, it is possible to prevent the bubbles from diffusing to the bottom of the tank.
[0040]
In this way, in the present invention, by providing the cap 48 with the lower end opened in the nozzle 42, the gas blown into the cap 48 becomes a pressure corresponding to the liquid column pressure of the storage tank 10. Even if the pressure is reduced for a while, it becomes possible to always release the gas into the liquid under a constant condition, and the gas in the transport container 13 is released into the storage liquid until the pressure becomes the same as the liquid column pressure of the storage tank 10. Thus, it becomes possible to drop the pressure of the transport container 13 in a short time.
[0041]
The gas in the transport container 13 immediately after unloading has a pressure in the transport container 13 of about 0.5 to 0.6 MPa, which is sufficiently higher than the liquid column pressure in the storage tank 10, and the cap 48 and the baffle plate When gas is blown out from between 55, if the opening of the gas side on-off valve 22 of the transport container 13 is adjusted to adjust the amount of gas flowing through the pressure drop line 36, the pressure of the transport container 13 has dropped to some extent. Then, the gas side on-off valve 22 is fully opened, and the gas is released by the difference between the pressure in the transport container 13 and the liquid column pressure in the storage tank 10.
[0042]
In the embodiment of FIG. 1, the gas blowing device 40 is attached to the nozzle 42 of the pressure drop line 36 dedicated to blowing, but in a facility that does not receive simultaneously from a plurality of transport containers, it is attached to the nozzle of the liquid receiving line, The liquid container can be used to reduce the pressure of the transport container. The gas blowing device 40 is applied not only to the pressure drop of the transport container but also when the gas phase gas pressure in the adjacent storage tank is high, the gas is blown into the other storage tank via the gas blowing device 40 to drop the pressure. Of course, it can also be applied to the system.
[0043]
【The invention's effect】
In short, according to the present invention, when the liquid inside the transport container is unloaded into the storage tank and the inside of the transport container that has become high pressure with the vaporized gas is dropped, the nozzle is provided with a cap whose bottom end is enlarged and opened. The gas from the nozzle is dispersed by hitting the gas dispersion plate in the cap, and the gas is released into the liquid storage through the diffusion holes provided in the cap. Regardless of the fluctuation of the gas, the gas can be uniformly blown into the liquid and absorbed under a constant condition.
[Brief description of the drawings]
FIG. 1 is an overall view showing an embodiment of the present invention.
FIG. 2 is a detailed view of the gas blowing apparatus of the present invention in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Storage tank 13 Transport container 36 Drop pressure line 42 Nozzle 46 Gas dispersion plate 48 Cap 52 Lower edge 53, 54 Dissipation hole 55 Baffle plate

Claims

When unloading the loaded liquid in the transport container to the storage tank, the liquid stored in the storage tank or other storage tank to be received is vaporized and gasified, and the gas is introduced into the transport container to reduce the pressure in the transport container. Using the pressure difference between the transport container and the storage tank to be received, the loaded liquid in the transport container is sent to the storage tank, and after the liquid transfer is completed, the high-pressure gas in the transport container is received from the pressure drop line. In a system in which the pressure in the transport container is reduced by blowing into a liquid in a storage tank or other storage tank through a nozzle, a gas dispersion plate having a diameter larger than the nozzle diameter is provided above the nozzle provided in the lower part of the storage tank. provided, the cap bottom has an opening which surrounds the top of the gas distribution plate and the nozzle is provided, and the cap, the lower end attached to the upper seal plate and the upper seal plate The high-pressure gas in the transport container blown from the nozzle is applied to the gas dispersion plate in the cap and dispersed and blown into the cap, and the blown gas is liquidated in the storage tank. The pressure in the cap is discharged, and the gas in the cap is discharged into the liquid storage in the storage tank through a number of diffusion holes formed in the upper seal plate and skirt of the cap, and the gas is absorbed in the liquid storage. Transport container pressure drop system.

A pressure drop in the transport container by blowing high-pressure gas from the transport container into a liquid in a storage tank or other storage tank that is received through a nozzle, which is used in the pressure reducing system for the transport container according to claim 1. In the apparatus for blowing gas into the storage tank, a gas dispersion plate having a diameter larger than the nozzle diameter is provided above the nozzle provided in the lower portion of the storage tank, and the lower end surrounding the gas dispersion plate and the upper portion of the nozzle is opened. the provided cap, and the cap, is formed with skirt attached bottom end has an enlarged diameter at the top seal plate and the top seal plate, characterized in that a plurality of diffusion hole to the upper sealing plate and the skirt of the cap A device for injecting gas into the storage tank.

The cap is formed in a conical shape or a pyramid shape by an upper seal plate and a skirt having an enlarged lower end. The skirt is supported by the nozzle through a nozzle support, and a diffusion hole having a hole diameter of 5 to 10 mm is formed in the upper seal plate. The gas blowing apparatus for a storage tank according to claim 2, wherein the skirt is formed with a number of diffusion holes having a hole diameter of 5 to 15 mm.

4. The gas blowing device for a storage tank according to claim 2, wherein a baffle plate having a diameter sufficiently larger than a lower end opening diameter of the cap is provided below the cap.

The gas blowing device to the storage tank according to any one of claims 2 to 4, wherein a lower edge of the cap is formed in a shape or a sawtooth shape in which a plurality of triangular cuts are formed along a circumferential direction.