Productivity Index HyBGC


Productivity Index for the Beam Gas Compressor®

Terminology:

  • BOTTOM HOLE PRESSURE - (BHP): The pressure in a well at a point opposite the producing formation.    
  • STATIC BHP: The pressure in a well at a point opposite the producing formation after the well has been shut in and the pressure has stabilized.    
  • FLOWING BHP or PRODUCING BHP: The pressure in a well at a point opposite the producing formation during the wells production process.    
  • STATIC FLUID GRADIENT: The pressure in PSI exerted by a column of fluid one-foot high. The fluid gradient for calculating normal pressure below surface at any point is .465 PSI per foot of fluid.    
  • STATIC FLUID LEVEL: The height the STATIC BHP can push and support the fluid column in a well that is shut in and the pressures have stabilized.    
  • FORMATION BACK PRESSURE: The restricting pressure exerted on the face of the formation by a column or fluid or surface pressure. Fluid column pressure (weight) and surface pressure (flow line) will place unnecessary back Pressure on the formation and restrict the wells ability to produce at its maximum production rate.    
  • DRAWDOWN: The difference between the reservoir pressure and the pressure at the bottom of the tubing (FLOWING BHP). If the PRODUCING BHP at the face of the formation can be reduced, this reduction of pressure constitutes DRAWDOWN. This pressure drop (DRAWDOWN) causes production flow into the well from the producing formation. The more DRAWDOWN the more PRODUCTION.    
  • PRODUCTIVITY INDEX (PI): The total number of barrels of liquid (oil & water) per day per each PSI of DRAWDOWN.
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The wells PI is the indicator of the wells ability to produce fluid.

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  • BOPD = Barrels of oil per day
  • BWPD = Barrels of water per day
  • SBHP = Static Bottom Hole Pressure
  • FBHP = Flowing or Producing Bottom Hole Pressure

This means - for this well, each PSI of DRAWDOWN or relief of FORMATION BACK PRESSURE against the face of the formation, the well will produce an additional .5 (one half) barrel of liquid per day.

If this well is producing against SURFACE BACK PRESSURE OF 30 PSI and this pressure was relieved with the BEAM GAS COMPRESSOR - the results would be:

PI X DRAWDOWN = INCREASE IN PRODUCTION .5 X 30 PSI = 15 BOPD INCREASE TOTAL PRODUCTION RATE = SBHP - PRODUCING BHP (FBHP) x PI

OR

200 - 100 x .5 = 50 BOPD (PRESENT PRODUCTION) Relieving the 30 PSI of BACK PRESSURE we reduced the FBHP FBHP 100 PSI - 30 PSI SURFACE PRESSURE = 70 PSI FBHP 200 PSI - 70 PSI x .5 = 65 BOPD (15 BOPD +)