Apparatus, system and method for pumping gaseous fluid

A system for pumping gaseous fluid from an underground well comprising:

• a vortex type gas separator between a centrifugal pump and an electric submersible pump seal section, the gas separator serving as an intake to the centrifugal pump and comprising:
• a rotatable shaft extending through the vortex type gas separator;
• an intake port;
• an impeller fluidly coupled to the intake port and secured to the rotatable shaft, the impeller configured to homogenize at least a portion of a gas and a liquid in a pumped fluid to obtain homogenized fluid, the impeller comprising:
• a top side open to the diffuser;
• and
• a truncated vane located at a mid-pitch location between at least two untruncated vanes starting from a bottom side of the impeller, wherein each vane extends substantially upstream along a surface of a hub that extends in an axial direction of the impeller;
• and
• a gas separation chamber downstream of the impeller, the gas separation chamber comprising an exit port that vents an unhomogenized gas into an annulus;
• and
• the centrifugal pump arranged to receive the homogenized fluid from the gas separation chamber.

A method for pumping gaseous fluid comprising:

• placing an electric submersible pump (ESP) assembly into a well containing a gaseous fluid, the assembly comprising one of a rotary type or a vortex type gas separator between a centrifugal pump and an ESP seal section;
• operating the assembly to induce the fluid to flow towards the surface of the well;
• minimizing phase separation of the fluid using a plurality of impeller and diffuser pairs located in the one of the rotary type or the vortex type gas separator to obtain substantially homogenized fluid;
• removing an unhomogenized gas from the assembly by inertia of rotating motion in a gas separation chamber of the one of the rotary type or vortex type gas separator;
• and
• lifting the homogenized fluid to the surface using the centrifugal pump;
• wherein the impeller comprises at least two untruncated vanes, and wherein a truncated vane is placed at a mid-pitch location between the at least two untruncated vanes starting from a bottom side of the impeller, wherein each vane extends substantially upstream along a surface of a hub that extends in an axial direction of the impeller.