Is it better to have water or no water in the LNG sump?

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A few days ago, I was chatting with an old friend and we discussed this issue. He said there are two opinions in his unit: one opinion is that it’s good to have water in the LNG liquid collection pit ； Another view is that there should be no water in the collection pit. When asked for my opinion, I answered straight away: Of course, water is better. There are two reasons: First, when determining the volume of the LNG collection pit, the volume of water was not taken into account; only the total volume of the leaked LNG and the thickness of the high-density foam were considered. If the presence of water inside is to be taken into account, the LNG sump should be larger. II. When LNG comes into contact with water, it undergoes a “rapid phase change,” commonly known as “cold explosion.” When LNG comes into contact with water under certain conditions, a explosive force can be generated. This phenomenon is called rapid phase transition (RPT). Although no combustion occurs, this phenomenon possesses all the other characteristics of explosion. When two liquids with a large temperature difference come into direct contact, if the thermodynamic (Kelvin) temperature of the hotter liquid is greater than 1.1 times the boiling point of the colder liquid, the temperature of the latter will rise rapidly, and its surface temperature may exceed the temperature for spontaneous nucleation (the formation of bubbles in the liquid). In some cases, superheated liquid will evaporate in a short time through a complex chain reaction mechanism, generating vapor at a rapid rate. For example, in experiments where LNG or liquid nitrogen is placed on water, the liquids can come into close contact through mechanical impact, thereby triggering a rapid phase transition. Some experiments conducted in Europe in the 1980s were used to train personnel involved in LNG operations and firefighting, among others. To avoid the so-called \"cold bounce,\" it is necessary to prevent LNG or liquid nitrogen from coming into direct contact with water; this also helps to minimize the accumulation of water in the LNG collection pit. If water does accumulate, it should be removed using a pump located in the LNG collection pit, until the liquid level is at its lowest possible level. The design of the LNG surface collection systems for some domestic projects is completely incorrect; the rainwater collection channels are used together with those for LNG, and rainwater is also discharged directly into the LNG collection pits.