Deliquification of Gas Wellsusing a

Multi-Channel System

TechCommCorp219 Blood Rd.Chester, VT 05143(802) 875-1200MWKen7@aol.com

Critical Flow Velocity

- Turner, Coleman and Li equations estimate critical gas flow velocity required to evacuate liquid from bottom of well

- Formula is based on empirical data from sample of gas wells using standard tubing of various diameters

- Formula ignores tubing diameter

Wallis Correlation

• In tubes of various diameter, estimates flooding velocity (velocity of upward flow of gas with falling film of liquid)

• Flooding velocity declines with tubing diameter

Wallis Correlation

As the tubing diameter decreases, the extent of energy transfer from the carrier phase (gas) to the carried phase (liquid) increases, resulting in a

decline in slippage of the gas phase (decline in GLR)

Small-Diameter Air-Lift Pumps

• “Two important effects become significant when the airlift tube diameter is below about 20mm. The first is the increase in the importance of surface tension. The second is the reduced Reynolds Number.” (Reinemann, 1989)

Airlift Pump Tubing Diameter

• “Efficiency” of the carrier phase (gas) increases at an increasing rate as diameter is reduced from 20mm to 6mm in air-water systems, especially from 12mm to 6mm

• Corresponding decline in slippage of the gas phase past the liquid (lower GLR)

• At 6mm diameter, slippage approaches zero• Permits targeting a desired GLR by virtue of

diameter selection

Efficiency of Airlift Pumps

Tubing Performance Curve

MCS Extrusion

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MCS Tubing Performance Curve

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MCS Tubing Performance Curve

MCS vs. Velocity String

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Pilot MCS Gas Well Installation

• 1,930-foot gas well, no packer• Peak gas flow rate 120Mcf per day• Currently, 280# BHP and 70# line pressure• Pre MCS installation, 2-week intermittent

slugging cycle (soap sticks)• Water salinates > 130,000 ppm NaCl

equivalent

MCS Pilot Well Performance

• Post MCS Installation: automatic kick-off with 3-days for evacuation of 360’ of accumulated liquid, then steady-state flow thereafter

• 3 plus years with no maintenance• Production increased by 30%, to 20Mcf and

2.7Bbl of water per day (~ 130Bbl/MMcf)• Sub-zero weather had no affect on production

Flow Quality up Pilot Well

• Incredibly flat line on gas production chart• Calculated gas flow velocity: 4.4 fps at well

bottom and 11 fps at wellhead• Under 1 foot of water in 1,930-foot column

when condensed/concentrated (like a “moving cloud” of mist-vapor up the column)

• Minimum “critical flowrate” estimated at ~ 1 fps to maintain continuous liquid evacuation

Other Potential Applications

• Reduces slippage of the gas phase in oil wells: significantly extends the natural flowing phase and uses much less gas during artificial gas lift

• Dual pipeline (one conventional line for pigging and a second line for an MCS) on hills or underpasses to prevent slug formation

• Dual pipeline approaching processing facilities to protect against long slugs (water hammer)

• Dual riser with MCS to reduce GLR during annular flow and to eliminate slugging problems

• Offshore jumper lines to minimize gas slippage