Tag: reservoir surveillance

Experimental Investigation of Polymer Degradation and Its Effects on Electrical Submersible Pump Operation

Publicado em por .
Polymer solutions are essential in enhanced oil recovery (EOR) for flooding applications but are susceptible to mechanical degradation, which severely impacts its rheological behavior. In this study, we examine the degradation of sulfonated polyacrylamide (SPAM) in a flow loop simulating an oil production system with an electrical submersible pump (ESP). The effects of the non-Newtonian fluid on ESP performance were analyzed under different operational conditions of flow rate and rotational speed. The results identified that the ESP was not the primary contributor in the tested conditions, with the globe valve differential pressure as the most relevant contributor. The ESP exhibited a significant head reduction due to the solution’s effective viscosity. However, the required shaft power remained unchanged, as strong shear rates on the impeller’s external surface reduced viscosity due to the shear-thinning behavior of the solution. A model based on the first Newtonian plateau viscosity successfully estimated ESP performance and provided the shear rates within the pump. The head losses were attributed to low shear rates in the ESP diffuser and impeller channels, which can be associated with the increment of viscosity and friction losses.

Model-Based Petroleum Field Management in Three Stages: Life-Cycle, Short-Term, and Real-Time

Publicado em por .

The objective of this work is to present a new practical methodology to manage petroleum fields considering three stages (life-cycle, short-term, and real-time) that can run alongside different model fidelities and characteristics. The model-based field management process follows the general methodology proposed by Schiozer et al. (2019) with four activities: (1) fit-for-purpose models construction, (2) data assimilation for uncertainty reduction, (3) life-cycle production optimization and (4) short-term optimization for real-time implementation. The selection of the production strategy for field management comprehends the last two activities. Life-cycle optimization is the first stage of the process and generates control setpoints for short-term analysis. Short-term optimization is then used to improve the quality of the solutions considering the control parameters of the next cycle (considering a closed-loop procedure). Real-time solution is then implemented considering operational disturbances from real operations. The methodology was applied to a benchmark case (UNISIM-IV-2026) which is a case based on a typical carbonate field from the Brazilian Pre-salt, with light oil and submitted to Water-Alternate-Gas injection with CO2 (WAG-CO2). The results show that the methodology is applicable to real and complex fields. As the three stages can run simultaneously, one can (1) use different model fidelities to improve the quality of the solutions and (2) use model-based solutions for real-time implementation. Life-cycle optimization using complex simulation models and long-term objectives can run in the background to generate control setpoints for short-term analysis in which lower fidelity models and simplified solutions can be used for the control and field revitalization parameters of each closed-loop cycle. Real-time solutions can be implemented considering operational problems and disturbances. This work presents a novel procedure to integrate three stages for production optimization that can run in parallel, allowing the integration of life-cycle and real-time solutions. The methodology (1) allows the use of complex reservoir simulation models from the life-cycle production strategy optimization, (2) focuses short-term control parameters that improve the quality of the short-term solution, and (3) guides real-time implementation, so it can be the basis to a digital field management.