Purifying and liquefying system for helium with high hydrogen content

The invention relates to the technical field of chemical gas separation and liquefaction, and provides a high-hydrogen-content helium purification and liquefaction system which comprises a hydrogen-helium separation subsystem, a trace dehydrogenation subsystem, a low-temperature purification subsystem and a helium liquefaction subsystem. The hydrogen-helium separation subsystem comprises a dehydrogenation unit, a neon removal unit, a liquefaction unit and a refrigeration unit which are integrated in a cold box; the dehydrogenation unit is arranged on the upstream of the trace dehydrogenation subsystem, the low-temperature purification subsystem and the neon removal unit are sequentially arranged on the downstream of the trace dehydrogenation subsystem, the liquefaction unit and the helium liquefaction subsystem are respectively arranged on the downstream of the neon removal unit, and the refrigeration unit provides cold energy for the dehydrogenation unit, the neon removal unit and the liquefaction unit in a