Abstract: Hydrogen unloading and filling are the main process operations of hydrogen refueling station. The study found that the volume ratio of hydrogen container and the operation sequence have an impact on gas extraction rate during the unloading of hydrogen refueling station. When the unloading sequence is high pressure, medium pressure and low pressure and the volume ratio of hydrogen container is 2 (high pressure): 3 (medium pressure): 4 (low pressure), the gas extraction rate of tube trailer reaches 63%, higher than the gas extraction rate when the total water volume is the same but the volume ratio of hydrogen container changes to 1:1:1. The gas extraction rate in the unloading sequence of high pressure, medium pressure and low pressure is slightly higher than that in the reverse sequence of low pressure, medium pressure and high pressure. When filling hydrogen into hydrogen fuel cell vehicles, it was found that in the filling sequence of low pressure to high pressure hydrogen containers, the gas extraction rates under the tank volume ratio of 2:3:4 and 1:1:1 were roughly the same. In addition, when hydrogen is directly filled using hydrogen compressor, the gas extraction rate is higher than that of the scheme using hydrogen containers. The filling demand at peak hours can be met by increasing the capacity of single hydrogen compressor or by connecting multiple compressors in parallel. This research conclusion can provide data support and guidance for the engineering design, standard formulation and on-site operation and maintenance of hydrogen refueling stations.

Key words: hydrogen refueling station, hydrogen unloading, hydrogen filling, gas extraction rate, direct hydrogen filling