Report

Foam Flow Instability Analysis Shu Luo The University of Tulsa Foam Flow Meeting, Jul.9th, 2013 1 Outline • Introduction • Liquid Holdup in Foam • Foam Flow Stability • Foam Flow Pressure Drop • Summary Foam Flow Meeting, Jul.9th, 2013 2 Introduction • Liquid holdup in foam flow is much lower than • • air-water flow Liquid holdup in foam flow is a function of liquid and gas velocities, as well as surfactant concentration At high concentration, liquid holdup almost remains constant at different gas velocities Foam Flow Meeting, Jul.9th, 2013 3 Foam Flow Liquid Holdup 2 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 4 Foam Flow Liquid Holdup • Predicting liquid holdup in large facility based • • on lab data from small facility Half life analysis reveals the effectiveness of surfactant at different concentrations Drainage velocity can be calculated from half life data, which relates to the slippage between gas and liquid Foam Flow Meeting, Jul.9th, 2013 5 Half Time Analysis Small Scale Foam Flow Meeting, Jul.9th, 2013 6 Drainage Velocity Calculation • Using half time analysis data (thalf) from small scale facility to calculate drainage velocity: / = (/) ℎ • Then, comparing drainage velocity with liquid holdup in foam flow Foam Flow Meeting, Jul.9th, 2013 7 Drainage Velocity vs. Liquid Holdup Foam Flow Meeting, Jul.9th, 2013 8 Liquid Holdup Correlation • Liquid holdup in foam is proportional to drainage velocity and liquid velocity, and inversely proportional to gas velocity = 2327 3.83 0.39 • This correlation Implicitly includes the effect of surfactant concentration through drainage velocity Foam Flow Meeting, Jul.9th, 2013 9 Liquid Holdup 800 ppm, 2 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 10 Liquid Holdup 1600 ppm, 2 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 11 Liquid Holdup 3000 ppm, 2 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 12 Liquid Holdup 800 ppm, 2 inch, vsl=0.03 m/s Foam Flow Meeting, Jul.9th, 2013 13 Liquid Holdup 1600 ppm, 2 inch, vsl=0.03 m/s Foam Flow Meeting, Jul.9th, 2013 14 Liquid Holdup 800 ppm, 4 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 15 Liquid Holdup 1600 ppm, 4 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 16 Liquid Holdup 3000 ppm, 4 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 17 Liquid Holdup 800 ppm, 4 inch, vsl=0.03 m/s Foam Flow Meeting, Jul.9th, 2013 18 Liquid Holdup 1600 ppm, 4 inch, vsl=0.03 m/s Foam Flow Meeting, Jul.9th, 2013 19 Experiment vs. Calculation Foam Flow Meeting, Jul.9th, 2013 20 Liquid Loading for Foam • Conventional definition is difficult to apply for • • foam flow Definition based on negative frictional pressure gradient (liquid film reversal) can be applied We applied this definition to predict the stability of foam flow Foam Flow Meeting, Jul.9th, 2013 21 Traditional Definition (dp/dz) 2 inch, 0.01 m/s Foam Flow Meeting, Jul.9th, 2013 22 Traditional Definition (dp/dz) 4 inch, 0.01 m/s Foam Flow Meeting, Jul.9th, 2013 23 dP/dz)G vs. dP/dz)F 400 ppm, 2 inch, vsl=0.01 m/s 6 m/s Foam Flow Meeting, Jul.9th, 2013 24 dP/dz)G vs. dP/dz)F 800 ppm, 2 inch, vsl=0.01 m/s 4.3 m/s Foam Flow Meeting, Jul.9th, 2013 25 dP/dz)G vs. dP/dz)F 1200 ppm, 2 inch, vsl=0.01 m/s 3.2 m/s Foam Flow Meeting, Jul.9th, 2013 26 dP/dz)G vs. dP/dz)F 1600 ppm, 2 inch, vsl=0.01 m/s 1.4 m/s Foam Flow Meeting, Jul.9th, 2013 27 dP/dz)G vs. dP/dz)F 3000 ppm, 2 inch, vsl=0.01 m/s 2.4 m/s Foam Flow Meeting, Jul.9th, 2013 28 dP/dz)G vs. dP/dz)F 400 ppm, 4 inch, vsl=0.01 m/s 15 m/s Foam Flow Meeting, Jul.9th, 2013 29 dP/dz)G vs. dP/dz)F 800 ppm, 4 inch, vsl=0.01 m/s 14 m/s Foam Flow Meeting, Jul.9th, 2013 30 dP/dz)G vs. dP/dz)F 1200 ppm, 4 inch, vsl=0.01 m/s 8 m/s Foam Flow Meeting, Jul.9th, 2013 31 dP/dz)G vs. dP/dz)F 1600 ppm, 4 inch, vsl=0.01 m/s 4 m/s Foam Flow Meeting, Jul.9th, 2013 32 dP/dz)G vs. dP/dz)F 3000 ppm, 4 inch, vsl=0.01 m/s 6 m/s Foam Flow Meeting, Jul.9th, 2013 33 Foam Flow Stability (Consistent with Small Scale) 1200 ppm Foam Flow Meeting, Jul.9th, 2013 34 Pressure Gradient Calculation • We subtracted gravitational gradient from • • overall pressure gradient to calculate frictional gradient. We use the frictional pressure gradient to back calculate viscosity We plotted the apparent viscosity as a function of gas velocity Foam Flow Meeting, Jul.9th, 2013 35 Viscosity vs. Gas Velocity 1200 ppm, 2 inch Foam Flow Meeting, Jul.9th, 2013 36 Observations • Viscosity of foam is close to water at low gas • • • velocities At very high gas velocities, the viscosity is closer to gas viscosity For a simple correlation, we propose 4 = 0.0026 −0.24 ∗ 1200 We used this correlation to calculate the frictional pressure gradient Foam Flow Meeting, Jul.9th, 2013 37 Total dP/dz 400 ppm, 2 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 38 Total dP/dz 800 ppm, 2 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 39 Total dP/dz 1200 ppm, 2 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 40 Total dP/dz 1600 ppm, 2 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 41 Total dP/dz 3000 ppm, 2 inch, vsl=0.01 m/s Foam Flow Meeting, Jul.9th, 2013 42 Total dP/dz 400 ppm, 2 inch, vsl=0.03 m/s Foam Flow Meeting, Jul.9th, 2013 43 Total dP/dz 800 ppm, 2 inch, vsl=0.03 m/s Foam Flow Meeting, Jul.9th, 2013 44 Total dP/dz 1200 ppm, 2 inch, vsl=0.03 m/s Foam Flow Meeting, Jul.9th, 2013 45 Total dP/dz 1600 ppm, 2 inch, vsl=0.03 m/s Foam Flow Meeting, Jul.9th, 2013 46 Summary • • • • A correlation of liquid holdup in foam flow is developed, which uses information from small facility. Foam flow Stability is determined based on film reversal phenomenon Critical velocity of foam flow decreases as surfactant concentration increases for both 2” and 4” A correlation of viscosity is proposed to calculate pressure gradient of foam flow. Foam Flow Meeting, Jul.9th, 2013 47 Thank You! Questions… Foam Flow Meeting, Jul.9th, 2013 48