JP3372343B2 - Dangerous gas diffusion promotion method - Google Patents
Dangerous gas diffusion promotion methodInfo
- Publication number
- JP3372343B2 JP3372343B2 JP06835794A JP6835794A JP3372343B2 JP 3372343 B2 JP3372343 B2 JP 3372343B2 JP 06835794 A JP06835794 A JP 06835794A JP 6835794 A JP6835794 A JP 6835794A JP 3372343 B2 JP3372343 B2 JP 3372343B2
- Authority
- JP
- Japan
- Prior art keywords
- gas
- liquid
- temperature
- diffusion
- foaming agent
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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Description
【発明の詳細な説明】
【０００１】
【産業上の利用分野】本発明は各種可燃性あるいは有毒
性液体を貯蔵するタンクから液体が漏洩した際に発生す
る危険性ガスを速やかに希釈、拡散させるための危険性
ガス拡散促進方法に関する。
【０００２】
【従来の技術】液化天然ガス（ＬＮＧ）、液化石油ガス
（ＬＰＧ）、液体水素、液体酸素などの可燃性液体ある
いはメタノールなどの毒性を有する液体の貯蔵タンクを
備えた設備において、液体の漏洩があった場合には、危
険防止のためできるだけ早急に漏洩した液体からの蒸発
ガスを希釈、拡散させることが必要である。例えばＬＮ
Ｇ基地では、大気中への拡散濃度を希薄にするためＬＮ
Ｇタンクを囲む形で防液堤を設置し、防液堤の高さを
漏洩想定時の液体面の高さの数倍とすることで拡散源高
さを高くする方法、漏洩したＬＮＧ液面上にＨｉ−Ｅ
ｘ（商品名：Hight-Expansion-Foam）等の高発泡剤を散
布し、蒸発ガスを昇温し拡散を促進する方法、防液堤
の外側に地上から垂直上方に高さ１０ｍ程度の水幕をつ
くり、拡散源高さを高くすると同時に蒸発ガスを昇温す
る方法等が取られている。
【０００３】
【発明が解決しようとする課題】ＬＮＧ、ＬＰＧ、液体
水素、液体酸素などの可燃性液体あるいはメタノールな
どの毒性を有する液体が流出すると、地面や大気から熱
を受けて蒸発し、大気中へ拡散する。これらの蒸発ガス
は、蒸発ガスが低温であったり、常温であっても分子量
が大きく、空気より比重が大きいものが多い。比重が大
きいガスの拡散は、通常重力拡散と呼ばれる形態で拡散
し、その拡散速度は極めて小さく、可燃性液体あるいは
有毒な気体の塊が地上に形成され、蒸発が進むにつれて
その体積は増大する。これは、地上における風は通常、
地面と平行方向の成分の速度が主で、比重の重い気体の
塊の中に風が流入しにくいことに起因している。通常、
ＬＮＧ以外の液体についても前記〜のような方法で
拡散を促進し、希薄化させる対策が施されているが、こ
れらの方法は設備費が膨大となるばかりでなく次のよう
な問題点がある。すなわち、の防液堤を高くする方法
では、防液堤を越えたガスが再び堤の外で重力拡散す
る。またの水幕を設ける方法では、発泡剤の昇温効果
の持続性が短い、大量の水を要するためコストが高い、
風上側には設置不可能（液体に水がかかると蒸発速度が
増大して大量の蒸発ガスが瞬時に発生し、爆発性ガスが
大量に形成され、危険である）、水幕を通り抜けるガス
量が多い、などである。
【０００４】さらにの高発泡剤によりガスを昇温させ
る方法については、次のとおりである。例えば、ＬＮＧ
タンクからＬＮＧが流出したときには、流出と同時に高
発泡剤がＬＮＧ液面上に散布される防災システムがしば
しば用いられる。この高発泡剤の作用は大気からＬＮＧ
への熱流束を抑制してＬＮＧ蒸発速度を減少させ、さら
に地上からの熱で蒸発した極低温気体（ＬＮＧでは約−
１８０℃）の温度を−１００〜０℃に上昇させることに
よって、大気の比重と同程度以下に軽くすることによっ
て大気中への拡散を促進するものである。しかしなが
ら、ＬＮＧから蒸発したガスは高発泡剤の層の中に形成
される流路を通って高発泡剤の層の上に出るが、その流
路数は１ｍ2 当たり２〜４個程度であることが実験によ
り確かめられた。さらに時間が経過するにつれてガス流
路の壁面は凍結し、高発泡剤のガス昇温効果は大きくは
ない。すなわち、ガスと高発泡剤との間で熱交換し、ガ
スの昇温に寄与する位置はガスが高発泡剤を通過する際
の接触面積つまり高発泡剤に形成される穴の数によって
決まる。従来、この穴の数を強制的に増加させる試みは
成功されておらず、高発泡剤の量、すなわち高さを３ｍ
以上高く積み上げる対策が取られており、大量の高発泡
剤が必要であった。本発明は前記従来技術における問題
点を解決し、漏洩した危険性液体を速やかに蒸発、揮散
させることができ、高い防液堤や水幕の形成を必要とし
ない危険性ガス拡散促進方法を提供するものである。
【０００５】
【課題を解決するための手段】本発明は貯蔵タンクから
漏洩した危険性液体から蒸発するガスを希釈するための
拡散促進方法であって、防液堤内に溜まった液体の液面
上に高発泡剤を散布して高発泡層を形成させ、該高発泡
層に一時的あるいは間欠的に投石するか、又は該高発泡
層の下部に金網を設けることによって、該高発泡層に１
ｍ2 当たり１０個以上の、液面から高発泡層の上面に貫
通する通気孔を生じさせることを特徴とする危険性ガス
拡散促進方法である。
【０００６】
【作用】低温ガスあるいは空気以上の比重のガスは地上
から上空に向かって層をなす形態で、すなわち地上付近
の漏洩した液体の表面に形成された濃度１００％に近い
ガス塊が膨らむ形態で大気中に広がっていく。このガス
塊の拡散、希薄化はガス塊への周囲空気の流入（エント
レインメント）によってのみ起こる。一方、比重の小さ
いガスは浮力によって上方へ移動しながら拡散するため
希薄化は早い。この空気のガス塊への流入による拡散は
ガス塊と空気との界面でのみ起こるため、１〜３ｍ／ｓ
程度の地上風の場合にはガスの発生速度が拡散速度を上
回ることが多く、ガス塊の体積は増大する一方である。
そこで本発明の参考例ではガス塊の内部において、上向
き速度成分を有する空気を吹き出させることによって、
ガス塊への空気の流入を強制的に行わせ、上方への拡散
促進、ガスの希薄化を行わせる。
【０００７】漏洩した液体の表面に高発泡剤を散布し高
発泡層を形成させると、ガスは高発泡層に形成される通
気孔を通って上昇し、高発泡層の上面から拡散してい
く。高発泡層に形成される通気孔を漏洩した液体が気化
した極低温ガスが通過する際のガスの昇温効果は主とし
て、（イ）通気孔の長さすなわち高発泡層の積み上げ高
さ、（ロ）通気孔の壁面の温度とガスの温度差及び
（ハ）単位面積当たりの通気孔の数に依存する。通常の
場合、（ロ）と（ハ）は制御不可能であり、従来は主と
して（イ）の観点から、すなわち高発泡層の高さを高く
する方向で対策が講じられていた。（ロ）の温度差につ
いては、通気孔形成の後、時間に対してほぼ指数関数的
に減少する。すなわち、通気孔の壁面のみがガスの通過
により凍結し、ガスと壁面の温度差が減少する。本発明
では、投石機を設けて一時的あるいは間欠的に高発泡層
に投石するようにしたり、高発泡層の下部に金網を設け
るなどの手段により、通気孔の数を強制的に増加させる
ようにしている。ガスの昇温効果は通気孔の数に比例し
て増加するので、少量の高発泡剤で大きな昇温効果を得
ることができるのである。
【０００８】ここで使用する高発泡剤は水と界面活性剤
を主体とする泡消化剤などに使用されているものであ
る。これらの高発泡剤はタンク内に液体として保管さ
れ、タンク外に放出すると体積が６〜１０００倍、好ま
しくは４００〜６００倍に膨張し泡状となる。そのた
め、ＬＮＧ、ＬＰＧ等の上に散布することで周りの空気
を遮断して爆発を防止したり、低温のＬＮＧ等を昇温し
て危険ガスの拡散と希薄化を促進する効果がある。高発
泡層の高さは１〜３ｍ程度とする。ＬＮＧの場合蒸発し
たＬＮＧガス（約−１８０℃）は高発泡層内を上昇し大
気中に出るまでに高発泡層から熱をもらい−１００〜０
℃まで昇温する。この場合、蒸発したガスは高発泡層内
に形成される通気孔を通って大気中に出るが、自然の状
態で形成される通気孔の数は１ｍ2当たり２〜４個程度
であるが、本発明ではこの数を１ｍ2 当たり１０個以上
に増加させる。
【０００９】
【実施例】以下実施例により本発明をさらに具体的に説
明する。以下の例ではＬＮＧ大量貯蔵基地において、Ｌ
ＮＧ貯蔵タンク１の不具合により、防液堤３の内部にＬ
ＮＧ２が流出した場合を想定している。（参考例）
図１は本発明の参考例を示す説明図である。漏洩したＬ
ＮＧ２の液面の最大高さ（ＬＮＧ貯蔵量と防液堤３の面
積から推定できる）より１０〜１００ｃｍ程度上方に内
径３〜１０ｃｍ程度の空気配管４を３〜１０ｍピッチで
防液堤３内に張りめぐらせておく。空気配管４には１〜
５ｍピッチで例えばベンチュリノズル５を設置し、空気
ブロワ６で空気配管４に空気を送ることにより防液堤３
内に上昇気流を生じさせることができる。これにより、
漏洩したＬＮＧ２の液面上のガスの上方への拡散を早め
ることができる。風量はＬＮＧの蒸発直後ガス比重を空
気と同程度にまで増加させるように設定するが、これは
地面の材質等からＬＮＧの蒸発量を推定し、計算でき
る。さらにベンチュリノズル５からの吹き出し方向は、
水平方向に対して４５〜９０度とし、民家等が無い方向
を予め設定しておくのが望ましい。この実施例によれ
ば、空気管がない場合には２〜３ｍ必要であった防液堤
の高さが、１ｍですみ、また、高発泡剤散布のための付
帯設備も不要となった。
【００１０】（実施例１）
図２は本発明の１実施態様を示す説明図である。この例
では漏洩したＬＮＧ２の表面に高発泡剤（フカダＨｉ−
Ｅｘ：深田工業（株）製、市販品）を散布し、高発泡層
７を形成させる。そして、この高発泡層７に形成される
通気孔８の数を増加させる手段として投石機９を設けて
いる。高発泡剤はある程度低温になるとシャーベット状
に凝固し、投石によって容易に直径５〜１０ｃｍ程度の
穴を開けることができ、通気孔８が形成される。時間が
経過し、通気孔８の壁面が凍結し昇温効果が小さくなっ
たときに、再度投石し、新たな通気孔８を形成させるの
が効果的である。時間の経過と高発泡層の上面に出てく
るガスの温度との関係を図４に示す。投石なしの場合に
は通気孔の壁面が凍結し、図の点線に示すようにガス温
度は急激に下降するが、投石を断続的に行うことによっ
て新たな通気孔を形成させることによりガス温度上昇効
果を継続させることができることが分かる。
【００１１】（実施例２）
図３は本発明の第２の実施態様を示す説明図である。こ
の例では実施例１の投石機の代わりに漏洩したＬＮＧ２
の上方、高発泡層の下部に５〜１０ｃｍ角の金網１０を
設置することにより通気孔８の数を増加させている。金
網１０の設置位置は想定される液体の最大高さより２０
〜１００ｃｍ上方とし、高発泡剤の散布ノズルは漏洩し
たＬＮＧ２の液面と金網１０との間に設けるのが好まし
い。この場合の時間の経過と高発泡層の上面に出てくる
ガスの温度との関係を図５に示す。金網は高発泡層に形
成される通気孔の数を飛躍的に増加させる。蒸発ガスの
全体量は一定なため、一つの通気孔を通過するガス量は
通気孔の数に反比例して減少するので、通気孔の壁面の
温度の低下が緩やかとなり（図の点線）、通気孔壁面が
凍結し、蒸発直後のガス温度と同じ温度になるまでの時
間を延ばすことができる（図の実線の部分）。
【００１２】
【発明の効果】高発泡剤を使用しない場合、従来のよう
に空気の供給を行わないと、先ず防液堤内部全域にわた
ってガス塊が形成され、時間が経過するとガス塊は防液
堤を越えて地面をはう形で拡大する。その場合、防液堤
の働きはガスの拡散源の高さを増加させる効果のみであ
る。一方、参考例のようにガス塊の内部から上昇気流を
生じさせると、ガスの拡散、希薄化が極めて容易に起こ
り、通常防液堤の外側に設置される水幕等の設備が不要
となる。また、防液堤の高さも従来の設備では想定され
る液面高さの数倍必要であったものが、１．１〜１．２
倍程度で済む。本発明の方法では、高発泡剤を使用し、
高発泡層に形成される通気孔の数を強制的に多くするよ
うにしているので、危険ガスの昇温効果が大きく、すみ
やかに昇温させて比重を小さくし、拡散させることがで
きる。さらに、投石機のような手段により、通気孔の数
を増加させる場合には、通気孔壁面の温度が低下した時
点で再度投石などの操作を行うようにすれば、ガス温度
上昇効果を継続させることができる。このようにガスの
昇温効果が大きいので、高発泡剤の使用量を減少させる
ことができる。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention rapidly dilutes and diffuses a hazardous gas generated when a liquid leaks from a tank storing various flammable or toxic liquids. Dangerous gas diffusion promotion method for 2. Description of the Related Art In a facility equipped with a storage tank for a flammable liquid such as liquefied natural gas (LNG), liquefied petroleum gas (LPG), liquid hydrogen or liquid oxygen, or a toxic liquid such as methanol, a liquid is used. In the event of leakage, it is necessary to dilute and diffuse the evaporative gas from the leaked liquid as soon as possible to prevent danger. For example, LN
At the G base, LN is used to reduce the concentration of diffusion into the atmosphere.
A method of increasing the height of the diffusion source by setting up a dike around the G tank and making the height of the dike several times the height of the liquid surface at the time of the leak assumption. Hi-E on top
x (trade name: High-Expansion-Foam), a method of spraying a high-foaming agent, etc. to raise the temperature of the evaporative gas to promote diffusion. A water curtain with a height of about 10 m vertically above the ground outside the dike And increasing the height of the diffusion source and simultaneously raising the temperature of the evaporative gas. [0003] When a flammable liquid such as LNG, LPG, liquid hydrogen or liquid oxygen or a toxic liquid such as methanol flows out, it receives heat from the ground or the atmosphere and evaporates. Spreads in. Many of these evaporative gases have a high molecular weight even when the evaporative gas is at a low temperature or at room temperature, and have a greater specific gravity than air. The diffusion of a gas having a large specific gravity usually diffuses in a form called gravitational diffusion, the diffusion speed is extremely low, a flammable liquid or a toxic gas mass is formed on the ground, and its volume increases as evaporation proceeds. This is because wind on the ground is usually
This is mainly due to the velocity of the component in the direction parallel to the ground, which is due to the difficulty of wind flowing into the mass of gas having a high specific gravity. Normal,
For liquids other than LNG, measures are taken to promote diffusion and dilute liquids by the methods described above. However, these methods not only increase the equipment cost but also have the following problems. . That is, in the method of increasing the height of the dike, the gas that has passed through the dike is gravitationally diffused outside the dike again. Further, in the method of providing a water curtain, the sustaining effect of the temperature raising effect of the blowing agent is short, and a large amount of water is required, so that the cost is high,
Can not be installed on the windward side (If water is splashed on the liquid, the evaporation rate will increase and a large amount of evaporative gas will be generated instantaneously, a large amount of explosive gas will be formed, which is dangerous), the amount of gas passing through the water curtain There are many. [0004] Further, a method of raising the temperature of the gas with a high foaming agent is as follows. For example, LNG
When LNG flows out of the tank, a disaster prevention system is often used in which a high foaming agent is sprayed on the LNG level at the same time as the LNG flows out. The action of this high foaming agent is LNG from the atmosphere.
To reduce the LNG evaporation rate by suppressing the heat flux to the cryogenic gas (about-
By increasing the temperature (180 ° C.) to -100 to 0 ° C., the diffusion into the atmosphere is promoted by reducing the specific gravity of the air to about the same or less. However, the gas evaporated from the LNG exits the layer of high foaming agent through the channels formed in the layer of high foaming agent, and the number of channels is about 2 to 4 per m 2. This was confirmed by experiments. Further, as the time elapses, the wall surface of the gas flow path freezes, and the gas heating effect of the high foaming agent is not large. In other words, the heat exchange between the gas and the high foaming agent and the position contributing to the temperature rise of the gas are determined by the contact area when the gas passes through the high foaming agent, that is, the number of holes formed in the high foaming agent. Conventionally, attempts to forcibly increase the number of holes have not been successful, and the amount of high foaming agent, that is, the height is set to 3 m.
Measures to build up the above were taken, and a large amount of high foaming agent was required. The present invention solves the above-mentioned problems in the prior art, and provides a method for promoting the diffusion of a dangerous gas, which can quickly evaporate and volatilize a leaked hazardous liquid and does not require the formation of a high liquid barrier or a water curtain. Is what you do. [0005] The present invention SUMMARY OF] is a diffusion enhancing method for diluting gas evaporated from danger liquid leaked from savings storage tank, the liquid level of the liquid collected in the liquid-proof Tsutsumiuchi by spraying a high blowing agent above to form a highly foamed layer, said high foaming
Temporarily or intermittently stoned layers or high foaming
By providing a wire mesh at the bottom of the layer,
A dangerous gas diffusion promoting method characterized by generating 10 or more vent holes per m 2 penetrating from the liquid surface to the upper surface of the highly foamed layer. A low-temperature gas or a gas having a specific gravity higher than that of air forms a layer from the ground to the sky, that is, a gas mass having a concentration close to 100% formed on the surface of the leaked liquid near the ground expands. Spread in the atmosphere in the form. The diffusion and dilution of the gas mass occur only by the inflow (entrainment) of ambient air into the gas mass. On the other hand, a gas having a low specific gravity is diffused while moving upward by buoyancy, so that the gas is quickly diluted. Since the diffusion due to the inflow of the air into the gas mass occurs only at the interface between the gas mass and the air, 1 to 3 m / s
In the case of moderate ground wind, the gas generation speed often exceeds the diffusion speed, and the volume of the gas mass is increasing.
Therefore, in the reference example of the present invention , by blowing air having an upward velocity component inside the gas mass,
The air is forced to flow into the gas mass to promote upward diffusion and to dilute the gas. When a high foaming agent is sprayed on the surface of the leaked liquid to form a high foaming layer , the gas rises through the air holes formed in the high foaming layer and diffuses from the upper surface of the high foaming layer. . The effect of increasing the temperature of the gas when the cryogenic gas vaporized from the liquid leaking from the air holes formed in the high foam layer passes is mainly (a) the length of the air holes, that is, the stacking height of the high foam layer, ( B) It depends on the difference between the temperature of the wall surface of the vent and the temperature of the gas and (iii) the number of vents per unit area. Normally, (b) and (c) cannot be controlled, and conventionally, measures have been taken mainly from the viewpoint of (a), that is, in the direction of increasing the height of the highly foamed layer. The temperature difference of (b) decreases almost exponentially with time after the formation of the air holes. That is, only the wall surface of the ventilation hole is frozen by the passage of the gas, and the temperature difference between the gas and the wall surface decreases. In the present invention, the number of air holes is forcibly increased by means of providing a trebuchet and temporarily or intermittently stoning the high foam layer, or providing a wire mesh under the high foam layer. I have to. Since the effect of increasing the temperature of the gas increases in proportion to the number of ventilation holes, a large amount of the effect of increasing the temperature can be obtained with a small amount of the high foaming agent. [0008] The high foaming agent used here is used for foam digesters mainly composed of water and a surfactant. These high foaming agents are stored as liquids in the tank, and when released outside the tank, expand to a volume of 6 to 1000 times, preferably 400 to 600 times, and become foamy. Therefore, spraying on LNG, LPG or the like has an effect of shutting off surrounding air to prevent explosion or raising the temperature of low-temperature LNG or the like to promote diffusion and dilution of dangerous gas. The height of the high foam layer is about 1 to 3 m. In the case of LNG, the evaporated LNG gas (about -180 ° C.) rises in the high-foaming layer and receives heat from the high-foaming layer before it goes out into the air.
Heat to ° C. In this case, the evaporated gas exits into the atmosphere through the air holes formed in the high foaming layer, and the number of air holes formed in a natural state is about 2 to 4 per m 2 , In the present invention, this number is increased to 10 or more per m 2 . The present invention will be described more specifically with reference to the following examples. In the following example, LNG mass storage
Due to the failure of the NG storage tank 1, L
It is assumed that NG2 flows out. (Reference Example) FIG. 1 is an explanatory view showing a reference example of the present invention. Leaked L
An air pipe 4 having an inner diameter of about 3 to 10 cm is provided about 10 to 100 cm above the maximum height of the liquid level of the NG 2 (which can be estimated from the amount of stored LNG and the area of the dike 3) at a pitch of 3 to 10 m inside the dike 3. Let it go around. 1 to air pipe 4
For example, a venturi nozzle 5 is installed at a pitch of 5 m, and air is sent to an air pipe 4 by an air blower 6 so that the liquid barrier 3
An updraft can be generated in the interior. This allows
The upward diffusion of the gas on the liquid level of the leaked LNG2 can be accelerated. The air volume is set so as to increase the gas specific gravity immediately after the evaporation of LNG to the same level as that of air. This can be calculated by estimating the evaporation amount of LNG from the material of the ground and the like. Further, the blowing direction from the venturi nozzle 5 is
It is preferable to set 45 to 90 degrees with respect to the horizontal direction, and set a direction in which there is no private house or the like in advance. According to this embodiment, the height of the dike required to be 2 to 3 m in the case where there is no air pipe is only 1 m, and no additional equipment for spraying the high foaming agent is required. (Embodiment 1) FIG. 2 is an explanatory view showing one embodiment of the present invention. In this example, a high foaming agent (Fukada Hi-
Ex: commercially available from Fukada Kogyo Co., Ltd.) to form the high foam layer 7. As a means for increasing the number of air holes 8 formed in the high foaming layer 7, a trebuchet 9 is provided. The high foaming agent solidifies in a sherbet shape when the temperature is lowered to some extent, and a hole having a diameter of about 5 to 10 cm can be easily formed by stoning, and the ventilation hole 8 is formed. When time passes and the wall surface of the ventilation hole 8 freezes and the effect of raising the temperature becomes small, it is effective to throw the stone again to form a new ventilation hole 8. FIG. 4 shows the relationship between the passage of time and the temperature of the gas emerging from the upper surface of the highly foamed layer. In the absence of stoning, the wall surface of the vent freezes and the gas temperature drops sharply as shown by the dotted line in the figure, but the gas temperature rises due to the formation of new vents by intermittent stoning. It turns out that the effect can be continued. [0011] (Embodiment 2) FIG. 3 is an explanatory diagram showing the second real embodiments with the present invention. In this example, the leaked LNG2 was used instead of the catapult of Example 1.
The number of the vent holes 8 is increased by installing a wire mesh 10 of 5 to 10 cm square above the high foamed layer above. The installation position of the wire mesh 10 is 20 times higher than the assumed maximum height of the liquid.
Preferably, the spray nozzle for the high foaming agent is provided between the liquid level of the leaked LNG 2 and the wire mesh 10. FIG. 5 shows the relationship between the lapse of time in this case and the temperature of the gas emerging from the upper surface of the highly foamed layer. The wire mesh dramatically increases the number of air holes formed in the highly foamed layer. Since the total amount of evaporating gas is constant, the amount of gas passing through one vent decreases in inverse proportion to the number of vents, so that the temperature of the wall surface of the vent decreases slowly (dotted line in the figure), The time required for the pore wall surface to freeze and reach the same temperature as the gas temperature immediately after evaporation can be extended (solid line in the figure). In the case where the high foaming agent is not used, if air is not supplied as in the prior art, first, a gas mass is formed over the entire area of the liquid barrier, and after a lapse of time, the gas mass becomes liquid-proof. It spreads over the ground over the dike. In that case, the function of the dike is only to increase the height of the gas diffusion source. On the other hand, when an upward air current is generated from the inside of the gas mass as in the reference example , gas diffusion and dilution occur very easily, and equipment such as a water curtain usually installed outside the dike becomes unnecessary. . Also, the height of the dike was required several times higher than the liquid level expected in the conventional equipment, but 1.1 to 1.2.
Only about twice. In the method of the present invention , a high foaming agent is used ,
Since the number of air holes formed in the high-foaming layer is forcibly increased, the effect of raising the temperature of the dangerous gas is large, and the temperature can be raised quickly to reduce the specific gravity and diffuse the gas. Furthermore, when the number of air holes is increased by means such as a stoning machine, if the operation such as stoning is performed again when the temperature of the air hole wall surface decreases, the gas temperature increasing effect is continued. be able to. Since the effect of increasing the temperature of the gas is large, the amount of the high foaming agent can be reduced.
【図面の簡単な説明】
【図１】本発明の参考例を示す説明図。
【図２】本発明の１実施態様を示す説明図。
【図３】本発明の第２の実施態様を示す説明図。
【図４】実施例１における時間の経過と高発泡層の上面
に出てくるガスの温度との関係を示すグラフ。
【図５】実施例２における時間の経過と高発泡層の上面
に出てくるガスの温度との関係を示すグラフ。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view showing a reference example of the present invention. FIG. 2 is an explanatory view showing one embodiment of the present invention. FIG. 3 is an explanatory view showing a second embodiment of the present invention. FIG. 4 is a graph showing a relationship between a lapse of time and a temperature of a gas appearing on an upper surface of a highly foamed layer in Example 1 . FIG. 5 is a graph showing the relationship between the lapse of time and the temperature of gas coming out on the upper surface of a highly foamed layer in Example 2 .
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) F17C 13/12 302 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 7 , DB name) F17C 13/12 302
Claims (1)
蒸発するガスを希釈するための拡散促進方法であって、
防液堤内に溜まった液体の液面上に高発泡剤を散布して
高発泡層を形成させ、該高発泡層に一時的あるいは間欠
的に投石するか、又は該高発泡層の下部に金網を設ける
ことによって、該高発泡層に１ｍ 2 当たり１０個以上
の、液面から高発泡層の上面に貫通する通気孔を生じさ
せることを特徴とする危険性ガス拡散促進方法。(57) [Claim 1] A diffusion promoting method for diluting gas evaporating from a hazardous liquid leaking from a storage tank, comprising:
Spray high foaming agent on the liquid surface of the liquid accumulated in the dike
A high foam layer is formed, and the high foam layer is temporarily or intermittently formed.
Stoned or provided a wire mesh under the high foam layer
By this, the high foamed layer has 10 or more pieces per 1 m 2
The method of promoting dangerous gas diffusion, characterized in that a vent hole penetrating from the liquid surface to the upper surface of the highly foamed layer is formed.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06835794A JP3372343B2 (en) | 1994-04-06 | 1994-04-06 | Dangerous gas diffusion promotion method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP06835794A JP3372343B2 (en) | 1994-04-06 | 1994-04-06 | Dangerous gas diffusion promotion method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH07280192A JPH07280192A (en) | 1995-10-27 |
| JP3372343B2 true JP3372343B2 (en) | 2003-02-04 |
Family
ID=13371481
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP06835794A Expired - Lifetime JP3372343B2 (en) | 1994-04-06 | 1994-04-06 | Dangerous gas diffusion promotion method |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3372343B2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106764406B (en) * | 2016-12-14 | 2019-06-14 | 西南石油大学 | A kind of LNG leakage emergency collection system |
| CN114294558B (en) * | 2021-12-21 | 2023-11-21 | 广东华南特种气体研究所有限公司 | Emergent evacuation equipment of LNG tank wagon |
-
1994
- 1994-04-06 JP JP06835794A patent/JP3372343B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07280192A (en) | 1995-10-27 |
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