Sealing system

A sealing system to prevent loss of a process fluid from a compressor to compress said process fluid from an inlet pressure to an outlet pressure higher than that of an inlet pressure, the compressor having an inlet section for receiving said process fluid at said inlet pressure, a device opening, a rotating member operable for rotational movement within said device opening, and a gear box from which said rotating member is driven, said sealing system comprising:

• a rotary shaft seal to provide a seal between said rotating member and said device opening, thereby to inhibit leakage of said process fluid from said device;
• a chamber externally connected to said device and aligned with said rotary rotating member seal to recover leakage of said process fluid from said rotary rotating member seal;
• the chamber having an outlet port and opposed inner and outer openings to allow said rotating member to project through the chamber:
• a barrier seal connected to said chamber, adjacent to said outer opening thereof, and having a bore to receive said rotating member and an inlet port in communication with said bore to inject a barrier fluid under a barrier seal pressure to prevent the escape of the process fluid from the outer opening of said chamber, the chamber thereby also receiving said barrier fluid through said outer opening;
• the barrier fluid being made up of lubricating oil providing lubrication within said gear box, the bore of said barrier seal being in communication with said gear box, opposite to said chamber, such that gear oil from said bore, at one end thereof, flows into said gear box;
• at least one filter connected to said outlet port of said chamber to separate said barrier fluid from said process fluid;
• and
• a return passageway in communication with said at least one filter and connected to said compressor so as to return said process fluid to said inlet section of said compressor.