Method and arrangement for recovering a helium product from natural gas by membrane unit

An arrangement for recovering a helium product, comprising:

• a first natural gas processing unit (10) and at least one second natural gas processing unit (20),
• means for supplying a first natural gas stream (1) containing helium to the first natural gas processing unit (10), and means for supplying at least one second natural gas stream (2) containing helium to the at least one second natural gas processing unit (20),
• at least the first natural gas processing unit (10) comprising helium recovery means (11) for forming the helium product from at least a part of the first natural gas stream (1), and
• a helium transfer section comprising a membrane unit (30), the helium transfer section at least temporarily performs a helium transfer from the at least one second natural gas stream (2) to the first natural gas stream (1) before the first natural gas stream (1) is provided to the first natural gas processing unit (10) and before the at least one second natural gas stream (2) is provided to the at least one second natural gas processing unit (20), wherein during the helium transfer the membrane unit removes helium from the at least one second natural gas stream (2) and the removed helium is transferred to the first natural gas stream (1).