Experimental study of inclined oil/water flow with separation

摘要

Gravity separation of oil and water flow in deviated wells and pipes has been observed in oilfield production logging as well as experimental studies. Several authors confirm that this effect is significant for a wide range of flow parameters. The present work investigates experimentally the possibility to use this effect for downhole oil/water separation. Oil/water separation experiments with Exxol D-60 and water have been performed at atmospheric conditions by using a 70 mm ID pipe inside a 100 mm ID pipe, for mixture velocities up to about 1 m/s. The measurements are used to validate a theoretical drainage model previously published by the authors. To achieve sufficient separator capacity for practical application, a number of drains along the pipe are required. The drain holes were pressure compensated to achieve a uniform drain rate, and a mathematical model for design of the pressure compensation scheme is presented, The authors have previously discussed the applicability of downhole gravity separation, and the present work further develops the basic understanding required for design of such a system. Additional applications of the separation method may be compact subsea or topside separation, or bulk water separators.