Hydrogen refuelling station with integrated metal hydride compressor: layout features and experience of two-year operation

Here, we present the details about layout and operation of the H2 refuelling station at Impala Platinum refineries in Springs, South Africa, since its start-up in October 2015 (officially launched on March 31, 2016). The station provides H₂ dispensing at the pressure up to 185 bar and uses pipeline H₂ (P~50 bar) available at the customer site. H₂ compression to P=200 bar with productivity up to 13 Nm³/h is provided by the integrated 1-stage metal hydride (MH) H₂ compressor which uses steam (T~130 °C) for the heating
and circulating water (T~20 °C) for the cooling; both steam and water are also available from the customer infrastructure. The station also includes H₂ dispenser, buffer tank (standard gas cylinder pack), and control block on the basis of Siemens Program Logic Controller (PLC) which provides fully automated system operation. Switching H₂ and steam / water flows is carried out with the help of remotely controlled, pneumatically actuated valves and auxiliary check valves. The H₂ discharge line is also equipped with a
safety relief valve for H₂ venting if overpressure (>210 bar) takes place. Additionally, at P=200 bar the control block switches the system into standby mode when both MH compression modules are cooled down and their gas manifolds are connected to the H₂ supply line. The H₂ dispensing is independent on the compressor operation and takes from 6 to 15 minutes.