The selection of completion equipment for artificial lift string for any field in the oil and gas industry is important for the safe and reliable operations of such a field. This is critical to the management and overall profitability of the oil and gas asset, especially in areas where artificial lift is the predominant means of water injection and hydrocarbon production. This paper focuses on why it is important to understand the saline subsurface and the total dissolved solids (TDS) of the environment in which the artificial lift completion is to be deployed and its impact on equipment selection. High concentration of corrosive components in the well fluid such as hydrogen sulfide, chlorine and total dissolved solids makes the well fluid conducive for electron migration. Such migration causes heavy corrosion, especially when dissimilar metals are used in artificial lift well completions. Carbon steel tubulars and casing are easily affected by such corrosive composition and leads to premature failure of artificial lift completions, which poses safety and operational issues. This type of environment is intense in electrical submersible pump completed wells because of the electromagnetic field generated by the current passing through the electrical cable of the pump system. A combination of field and laboratory data gathering, and analysis was utilized to determine the effect of the aggressive components of the produced fluid on electrical submersible pumps assembly. The contributions of the high total dissolved solids in the conductivity of the well fluid, and in the electrochemical process for metal corrosion were analyzed. It was evident from both forms and approaches utilized in the analysis that well fluid becomes an electrolyte that provided the desired path for electron flow, which was enhanced by the magnetic field of the ESP system cable. This paper highlights the integration of three approaches of geochemical analysis of well effluent, Anodic Index differential and tubular internal coating in corrosion prevention and electric submersible pump runlife elongation in wells with corrosive compositions including high total dissolved solids.

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Induction alternating current (AC) motors (IACM) have been used in electrical submersible pumps (ESP) due to them being more cost effective and easier to manufacture compared with other type of motors used in ESP systems. With increase of oil demand globally, the application of electrical submersible pump systems also increased. Therefore, optimizations of ESP systems are needed. This paper will discuss and simulate both types of ESP motors, which are: induction AC motor and permanent magnet motor in ESP systems, with emphasizes on why some application are better suited for permanent magnet AC motor and others for induction current type motor. The option of choosing the optimum motor type is dependent on multiple factors that may include: ESP design reliability, wellbore complexity and completion strings, production requirements, reservoir fluids characteristics, power supply limitations and ESP designs challenges.