Production Profiles Recorded Using Fiber-Optic Technology in Wells with Electrical Submersible Pump Lift System

Fiber-optic distributed sensor technology has rapidly evolved over the past 30 years, becoming very useful in the hydrocarbon sector for different operations, such as pipeline leak monitoring, production and injection logging, fracture monitoring, vertical seismic profiling, and steam injection, among others. Monitoring temperature is a critical aspect of reservoir development and a well’s life cycle, given its broad range of applications. Temperature profiling is commonly used in production logging, often in conjunction with other sensors to quantify and identify fluids. This paper discusses two prevalent scenarios encountered in the Llanos Orientales region of Colombia, where 28 wells with electrical submersible pump (ESP) lifting systems were impacted. During the execution of these fiber-optic logs, two conditions of particular interest were explored: wells with low-flow rates below 500 barrels per day and wells with mechanical limitations that preclude monitoring with conventional sensors due to the presence of stainless-steel bands at the bottom of the well. The fiber-optic string provided access to the drilling zone, enabling temperature and pressure monitoring of the production intervals. To interpret the data, a probabilistic model based on enthalpy balance, mass, and conservation of momentum was used to determine the well’s production profile.