Fluid recovery process and apparatus for xenon and or krypton recovery

A process for separation of a feed gas comprising oxygen, nitrogen, and argon, the process comprising:

• purifying a compressed feed gas via a pre-purification unit (PPU) before feeding the purified and compressed feed gas to a first separation system to form at least one product flow from the feed gas, the at least one product flow including a nitrogen flow, an oxygen flow, and/or an argon flow;
• outputting a first purge stream comprising xenon (Xe) and/or krypton (Kr) from the first separation system;
• splitting the first purge stream so that a first portion of the first purge stream is directed to at least one downstream processing unit (DPU) to form a first product flow comprising Xe and/or a second product flow comprising Kr and a second portion of the first purge stream is directed upstream of the PPU for undergoing additional purification via the PPU;
• and
• adjusting the splitting of the first purge stream so that a flow rate of the first portion of the first purge stream directed to the at least one DPU is decreased and a flow rate of the second portion of the first purge stream directed to the PPU is increased so that a fraction of the first purge stream that is recycled to the PPU is increased in response to a concentration of carbon dioxide (CO2) and/or nitrous oxide (N2O) meeting or exceeding a first pre-selected threshold value.