Liquid Loading

  • Reservoir pressure decline reduces the hydrocarbon production

    • Reduced gas velocity Vsg cause flow pattern change

Liquid Loading

    • Insufficient gas velocity

      • Vsg<Vsgcritical (Turner)

How to Avoid?

    • Artificial lift methods

      • Pumps
        • GLR limitations (ESP, Rod pump)
      • Reduce hydrostatic pressure
        • Plunger lift, gas lift, foam lift

Artificial Lift Method

    • Fluid properties ‘Heavy oil conditions more suitable for some methods’
    • High-GLR and deviation ‘Gas lock and deviated completions may reduce feasibility’
    • Limited application
      • Chemical composition
      • Works for short period

Plunger and gas lift are suitable for

  • Unconventional plays

    • Typically after six months

  • Production increase

  • Paraffin remediation

  • Low-cost solution

    • Cut lift expenditure

Pre-Liquid Loading

    • Natural flow

      • Stagnant film

    • Gas Lift

Continuous Plunger Lift

    • Dahlgren, 2019 (Southern Marcellus Wells)*

      • Gas production 15.5% ↑ (2389 mcf/d)
      • Liquid production 7% ↑ (69.4 bbl/d)

Liquid Loading

    • Intermittent Production
    • Gas Lift
      • High injection rates

Continuous Plunger Lift

    • Polasek, 2013 (Barnett&Glen Rose Well)*
      • Compressor removed 100% ↓ (~300 mcf/d)
      • Cut hot oil treatment

Plunger Assisted Gas Lift

    • Burns, 2018 (Barnett Shale Wells)*
      • Gas injection 78% ↓ (-355 mcf/d)
      • Gas production 14% ↑ (+50 mcf/d)

Low Preservoir

    • Intermittent production
    • Plunger Lift

Conventional Plunger Lift

    • EPA, 2006 (Midland Farm Field)*
      • Gas production +54% ↑
      • Avoid chemical treatment
    • Requires cycle optimization

.Low CapEX

  • Wireline installation
  • Cost $2-10k

.Min OpEx

  • No chemical injection or hot oil treatments
  • Reduced injection

.Shale Plays

  • Suitable for unconventional reservoirs, high GLR
  • Many candidate wells

Continuous Plunger Lift

 

Conventional Plunger Lift

Increase Production

  • Reduce $/Mcfe up to 15%

Cut Cost

  • Lower LOE
    • Gas lift
      • Reduce gas injection
      • Remove compressor ($/month)
    • Chemical injection ($/month)

Extend life of the well

  • Substantial cumulative production increase
  • Postpone plugging

Stabilize production

  • No venting
  • Limit workovers