How is the volume of the liquid collection tank in the LNG gasification station tank area calculated? ?

It cannot be less than the volume of a single largest storage tank.

On the 2nd floor, what was mentioned was a liquid collection tank, not a cofferdam.

I’m not sure what the purpose of that collection tank is. When LNG leaks out, it vaporizes immediately. Is that device meant for collecting rainwater? If it’s used to collect rainwater, then would measuring the rainfall amount be sufficient? I’m not an expert in water-related fields, so I’m not entirely sure~~~

It refers to the accident tank; there seem to be relevant requirements regarding its volume in the petroleum storage facility regulations

It is described in the fire protection design codes for petroleum and natural gas; I’m not sure if this is what you’re looking for. The code specifies the maximum possible leakage volume from a single source within 10 minutes

Paragraph 3 of clause 10.3.3 in GB50183-2004 states that \"Liquefied natural gas stations shall be equipped with a collection system for liquefied natural gas at low-temperature equipment and areas prone to leaks; the capacity of such a system should be no less than the tank capacity of the largest tank trucks for loading facilities, and it should also be sufficient to handle the maximum possible leakage volume from a single source of leak within 10 minutes.\"”； Clause 5.2.2.2 of GB/T20368-2012 also contains similar provisions ； According to clause 7.3 of GB/T22724-2008, \"when the distance between the retaining wall and the storage tank exceeds 15 m, it is necessary to consider installing a liquid collection tank; the volume of this tank should be equal to or greater than the amount of liquid that would overflow in the event of a pipe rupture, in order to enable detection and interruption of the flow.\"”

Our **LNG-related standards are still based on foreign standards. Whether in the United States, the European Union, or Australia, the principle for preventing fires resulting from LNG leaks is not to focus on measures to deal with fires once they occur, but rather to control the leaks and reduce the scope of damage caused by them. In complex fire situations, foam and firefighting water are ineffective; the purpose of firefighting water is merely to protect nearby equipment and property from damage caused by high temperatures. The liquid collection pits are designed to reduce the surface area available for LNG to evaporate (see AS3961 for details). When LNG leaks into the cofferdam, it has a large surface area, resulting in a high vaporization rate; by using small collection pits, its evaporation can be effectively reduced.

Thank you, I’ve learned something new. I’ll go take a look at the standards you mentioned~~~ Thank you~~~

Then may I ask, how is this maximum possible leakage volume determined? Is it based on the maximum flow rate of the pipeline?