A Novel Automatic Inflow-Regulating Valve for Water Control in Horizontal Wells

Abstract

Horizontal wells are prone to water coning and imbalanced inflow profile problems because of reservoir heterogeneity, the “heel-toe” effect, and different water avoidance heights. To solve these problems, an automatic inflow control device (AICD) technology is developed, as the traditional inflow control device (ICD) technology is frequently invalid after water breakthrough. In this study, a novel water control tool, an automatic inflow-regulating valve (AIRV), was designed to balance inflow profiles before water breakthrough and to limit water inflow after water breakthrough. With the use of a movable part, the AIRV can quickly distinguish fluids and limit the water output based on differences in fluid properties and the swirling flow principle. The water control efficiency and ability of the AIRV were simulated and optimized using computational fluid dynamics (CFD) software and verified experimentally using a water control testing system specially designed for the AIRV. We observed that (1) the total water force on the movable component of the AIRV is notably larger than that of oil because the swirling intensity of water is significantly higher than that of oil; moreover, the force directions of water and oil are opposite to each other. (2) The AIRV is sensitive to the flow rate and fluid viscosity but not to fluid density. (3) A higher water cut results in a higher AIRV pressure loss. The results of the CFD simulation and experimental test demonstrated that the AIRV has a significant water control ability and efficiency, particularly under conditions of a high production rate and high water cut. Thus, the AIRV can be used to enhance the control of water inflow before and after water breakthroughs in horizontal wells.

Design and Numerical Simulation Study of a Novel AICD for Water Control and Gas Production in Gas Wells

“…The automatic phase selection controller designed by Yang et al 48 is used to suppress water production after water breakthrough in bottom water coning reservoirs; its structure looks like a q shape, which mainly depends on the difference between oil and oil viscosity; water that rotates at a high speed in the tool produces a greater pressure drop than oil that does not rotate substantially. The new AICD designed by Li et al 49 is more suitable for horizontal wells in submerged reservoirs with high liquid production, and the automatic inflow-regulating valve (AIRV) designed by Cui et al 50 can be used to enhance the control of water inflow before and after water breakthroughs in horizontal wells. Natural gas as a clean energy, with its increasing consumption and the development of natural gas resources, has become a major focus of the global oil and gas industry, 20,22 the current demand for low-cost and efficient water control technology is huge, and the water control and gas production technology in gas wells with AICD as the core device is a low-cost, easy to operate, low-carbon environmental protection, and promising enhanced recovery technology to solve the current gas well water production problem.…”

“…The automatic phase selection controller designed by Yang et al 48 is used to suppress water production after water breakthrough in bottom water coning reservoirs; its structure looks like a q shape, which mainly depends on the difference between oil and oil viscosity; water that rotates at a high speed in the tool produces a greater pressure drop than oil that does not rotate substantially. The new AICD designed by Li et al 49 is more suitable for horizontal wells in submerged reservoirs with high liquid production, and the automatic inflow-regulating valve (AIRV) designed by Cui et al 50 can be used to enhance the control of water inflow before and after water breakthroughs in horizontal wells.…”

In-Depth Understanding of ICD Completion Technology Working Principle

“…The hydrodynamic profile was characterized for oil, gas, and water and even tested for different oils, and the performance curve was obtained by numerical means. Finally, Cui et al [17] proposed a new diode AICD, named automatic inflow-regulating valve, based on a parametric CFD study to, for example, find the optimal number of inlets and sizes to reduce excessive water production.…”