Vortex Pressure Reducing Station (VPRS)

The VPRS design concept is to provide non-freeze pressure reduction followed by thermal conditioning of the outlet stream of expanded/pressure reduced gas. A VPRS incorporates self-heating vortex tube(s) and a heat exchanger that is warmed by a low grade heat source which can often simply be ambient air. Pre-heat is not required for vortex pressure reduction as the high pressure gas undergoes non-freeze pressure reduction in UVI’s proprietary self-heating vortex tube.

The proposed VPRS configuration for most transmission & distribution applications is single stage vortex pressure reduction and thermal conditioning to achieve the design objectives described above. The configuration uses dual outlet VPR to enhance the available natural gas thermal conditioning. This configuration uses regulated variable VPR inlet pressure concurrent with a Gas Management System resulting in efficient operation throughout the range of design pressures and flow rates. While not specified the option for inter-stage storage to improve pressure and flow control exists. This design is well suited to transmission pressure reducing applications and key aspects of it are further described below.

Vortex pressure reduction and thermal management reduces or eliminates the requirement for power or natural gas for pre-heat as may be required to eliminate external ice or internal ice/hydrate formation in natural gas pressure reducing stations. Design of a pressure reducing station incorporating vortex pressure reduction and thermal management is based on the concepts of non-freeze pressure reduction as well as post pressure reduction heating from ambient air, ground source, solar or uses of waste heat or any low grade heat source. These concepts require consideration of mass and energy separation that is achieved in a vortex pressure reducer as well as heat exchange with potential heat sources. The more time spent gathering data in the conceptive, investigative, and preliminary stages, the better the design and the better will be all other aspects of the station.