The application of Electric Submersible Pump Systems (ESP) in harsh reservoir conditions such as high fluid viscosity (extra-heavy oil), high bottom hole temperatures, and high free gas content, represents technical and economic challenges due to low overall system performance and high operational costs associated to excessive energy consumption. This paper describes how Permanent Magnet Motors (PMM) summed up with different pump and gas separation technologies were designed, evaluated, and implemented to successfully overcome the described challenges, achieving greater system efficiency, and reduced energy consumption which translates into a reduced carbon footprint.
Several data were recorded from previous runs and nearby wells to understand equipment performance and kilowatts billing modes, including operational data, production tests, and energy consumption measurements. Considering all the gathered information, a non-standard completion was evaluated, designed, and successfully installed. It involved the review and selection of a suitable PMM ESP motor, and innovative technologies to mitigate the presence of high amounts of free gas including multiphase high efficiency pumps in combination with tandem gas separators.
The installation was executed according to well planning with good electrical readings before start-up. Function test was performed according to local procedures with expected response of the downhole equipment. The system has been closely monitored under remote surveillance, controlled by a variable speed drive and with strict follow-up of pressures, temperatures, vibrations, and VSD data. After 24 months of operation, relevant information has been collected, the equipment has been running under stable conditions and fluid production is according to expectations. Some relevant ESP performance parameters achieved so far are pump and motor working within recommended operating range with better system efficiency and less power consumption compared with the previous runs (up to 25%), power costs reduced by an average of 22%, power factor increased by up to 18%, and the equipment has shown great response to high temperatures and extreme well conditions. After the stabilization phase, production and applications engineers are assessing the reduction of greenhouse gases emitted by the indirect effect of the application of PMM motors as a great contribution to the long-term decarbonization strategy of the Operator (to reduce 25% of its CO2e emissions by 2030).
This paper shows a successful case study for the application of PPMs in ESP systems in wells impacted by harsh reservoir conditions where in the past standard Induction Motors (IM) were non-compliant with the Operator’s strategy for decarbonization. With this technology, the Operator expects to increase system efficiency, while reducing power consumption and carbon footprint. Based on the successful results from this first pilot, the operator is considering the expansion of this application throughout the Field.
