The setting of liquid collecting tanks is an important factor to be considered in the design of liquefied natural gas (LNG) terminals and cryogenic liquefied hydrocarbon terminals.At present，there is no uniform regulation on the volume of liquid collecting tanks in the code，and the design standards are different，resulting in a large difference in the volume of liquid collecting tanks in terminals of the same type and grade.In view of this problem，combined with engineering examples，this paper discusses the leakage scene and leakage time according to the requirements of the current standard.By comparative analysis，the paper suggests that the complete rupture of the loading arm and the leakage of the pipe hole should be considered comprehensively in the selection of leakage scenarios.At the same time，the leakage time should be selected based on the operation time after system detection and isolation，so as to determine the scale of the liquid collecting tank that conforms to the engineering practice and is economically feasible.The research results can provide a reference for the design of similar liquid collecting tanks in terminals.