A Revolutionary Packer Type Gas Separator that Involves Gravity Force to Exceed Traditional Gas Separation Efficiency in Oil and Gas Wells

Abstract

Abstract A revolutionary packer-type gas separator was designed to improve downhole gas separation efficiency. A deep analysis of gas separation methods was done to understand the process's nature and design a tool that could generate enhanced conditions for the gas separation phenomenon. During the research stages where data from Permian fields were analyzed to develop this new design of gas separator, the engineering team found three main challenges in downhole gas separation. First, the wells were converted from Electrical Submersible Pump (ESP) to Rod Pumps earlier, forcing the downhole gas separators to handle more production. Second, the small production casing size usually is 5.5" casing, which significantly reduces the annulus area, which is vital to get an effective gas separation efficiency, and third the gas slugging behavior, which in high proportion can lead to a gas lock-in sucker rod pump system. A packer-type gas separator was designed, built, and tested in multiple wells following the requirements and limitations. This gas separator has an outlet section of 1.89" O.D., which means the design maximizes the gas separation area where it really matters at the fluid outlet point. The revolutionary fluid exit slots design creates a linear flow path allowing gas to separate and flow upward the casing annulus in a natural way. Additionally, a valve below the cup packer was included to eliminate surging. This valve prevents surging by holding the fluid in the vertical section, thus avoiding backflow when the gas slug leaves liquids behind. A calculator was developed to estimate the gas separation efficiency downhole and compare the gas separation efficiency among different gas separators to evaluate the new design. After the implementation of this design in 5 wells, the results confirmed the high gas separation efficiency obtained with this new gas separator configuration. The novelty of this gas separator design is the outlet section that takes advantage of the gravity force to increase the gas separation efficiency without limiting the tensile strength of the Bottom Hole Assembly (BHA).