Abstract: A sealing system for process gas leakage from a turbomachine casing is provided. The sealing system may include a seal assembly housing coupled to or integral with the turbomachine casing. The seal assembly housing defines a bore configured to receive a rotary shaft and a sealing assembly. The sealing assembly includes a plurality of carbon rings mounted circumferentially about the rotary shaft. The plurality of carbon rings may include an inboard carbon ring configured to prevent flow of a separation gas inboard of the barrier seal, an outboard carbon ring configured to prevent flow of contaminates into the seal assembly housing, and an intermediate carbon ring interposed between the inboard carbon ring and outboard carbon ring. A pressure differential is maintained across the inboard carbon ring, such that the separation gas is prevented from flowing inboard across the inboard carbon ring by a residual portion of a seal gas.

Abstract: A sealing system for process gas leakage from a turbomachine casing is provided. The sealing system may include a seal assembly housing coupled to or integral with the turbomachine casing. The seal assembly housing defines a bore configured to receive a rotary shaft and a sealing assembly. The sealing assembly includes a plurality of carbon rings mounted circumferentially about the rotary shaft. The plurality of carbon rings may include an inboard carbon ring configured to prevent flow of a separation gas inboard of the barrier seal, an outboard carbon ring configured to prevent flow of contaminates into the seal assembly housing, and an intermediate carbon ring interposed between the inboard carbon ring and outboard carbon ring. A pressure differential is maintained across the inboard carbon ring, such that the separation gas is prevented from flowing inboard across the inboard carbon ring by a residual portion of a seal gas.