A seal includes a mating ring that rotates relative to a porous carbon primary ring at a seal interface. A buffer gas is provided into the seal and passes from the back of the primary ring to the seal interface. The seal can be used as a separation seal or in combination with another seal.

The invention relates to a shaft seal arrangement, comprising a first seal, a second seal and a third seal which are arranged in series between a product side to be sealed and an atmosphere side, wherein the second seal is arranged between the first seal and the third seal, wherein a first pressure is present in a space adjacent to the second seal in the direction towards the product side, and a second pressure is present in a space adjacent to the second seal in the direction towards the atmosphere side, wherein the space that is adjacent to the atmosphere side is connected to a pressure supply line via which a pressure medium can be supplied into the space, and wherein the first pressure is equal or substantially equal to the second pressure, so that the second seal can be operated with a pressure difference of zero between the first pressure and the second pressure.

Systems, devices, and methods for recovering mixed refrigerant and/or nitrogen within liquefaction systems are provided. The systems, devices, and methods facilitate recovering mixed refrigerant (MR) and/or nitrogen vapor that can leak from a compressor, separating the MR from the nitrogen, and reusing the MR and/or the nitrogen within the liquefaction system. Recovering and reusing MR and/or nitrogen can minimize loss of MR and nitrogen which can lower the total operating cost of a liquefaction system. Additionally, recovering the MR, rather than burning it, can reduce environmental emissions by reducing the amount of MR that is burned.

An assembly is provided that includes a shaft, a bearing, a stator seal element, a rotor seal element and a shield. The shaft extends along an axis. The bearing supports the shaft and receives lubrication fluid. The stator seal element circumscribes the shaft. The rotor seal element is mounted on the shaft axially between the bearing and the stator seal element. The rotor seal element forms a seal with the stator seal element. The shield substantially prevents the lubrication fluid from traveling axially away from the bearing onto the rotor seal element.

A seal monitoring and control system for a gas lubricated non-contacting seal includes various sensors providing signals to a programmable logic control system. The control system is disposed to determine a presence of an anomalous operating condition of the seal, for example, based on phase, relative position of rotor to stator or other signals in combination provided by the various sensors to provide an output signal, which in one embodiment performs at least one mitigating process to correct the anomalous operating condition by adjusting at least one operating parameter of the seal.

The invention relates to a gas-lubricated mechanical seal arrangement using a gaseous fluid as a barrier medium, comprising a mechanical seal comprising a rotating slide ring (2) and a stationary slide ring (3) defining a seal gap (4) therebetween, a biasing means (5) biasing the stationary slide ring (3) towards the rotating slide ring (2), a fluid space (6), into which the gaseous fluid can be introduced, a first slide ring carrier (20) for retaining the rotating slide ring (2), the first slide ring carrier (20) having a first axial surface (21), a second slide ring carrier (30) for retaining the stationary slide ring (3), the second slide ring carrier (30) having a second axial surface (31), the second slide ring (30) and the stationary slide ring (3) being arranged together on a displacement surface (32) so as to be displaceable in the axial direction (X-X), an axial gap (7), which is limited by the first axial surface (21) and the second axial surface (31), and an antechamber (8) which is formed at the sealing gap (4) of the mechanical seal and which is connected to the fluid space (6) via the axial gap (7).

A seal includes a mating ring that rotates relative to a carbon primary ring at a seal interface. A buffer gas is provided into the seal and passes from the back of the primary ring to the seal interface. The seal can be used as a separation seal or in combination with another seal.

A system and method for rapid pressurization of a motor compartment and cooling system during a shutdown, a surge, and/or other situations in which the suction pressure significantly varies. A motor/compressor arrangement includes a seal gas system fluidly communicating with the motor compartment via a motor pressurization line, with the outlet of the compressor, and with a shaft seal. A motor pressurization valve is coupled to the motor pressurization line and a controller is configured to open the motor pressurization valve at start-up of the motor-compressor to supply seal gas to the motor compartment and to pressurize the motor compartment when a difference between the seal gas supply pressure and the suction pressure is indicative of the seal gas supply pressure being insufficient.

A compressor arrangement having a main compressor, a piping system containing process gas to be extracted after the shut-down of the main compressor and one or more components emitting or leaking depressurized process gas while the compressor is operating or starting up; the compressor arrangement further comprises one or more collectors arranged to collect the depressurized process gas emitted from said components and an additional compressor fluidly coupled with the piping system and with the collectors in in order to compress the depressurized process gas coming from the components while the compressor is starting up or operating and to compress process gas coming from the piping system after a shut-down of the compressor.

A dry gas mechanical seal system configured to inhibit the emission of process gas. The mechanical seal system having tandem first and second stage seals, and a single separation gas supply subsystem configured to direct a supply of separation gas from an inlet through interfacing portions of the first stage seal into a process cavity and from the inlet through the interfacing portions of the second stage seal and out through an outlet to the atmosphere, thereby inhibiting the emission of process gas between a compressor housing and a rotating compressor shaft.