How do you design and implement a pilot test for a new thermal EOR method?

In our paper (SPE-177984-MS), we outlined key steps for selecting a pilot area, focusing on three factors: Minimize Pilot Cost: Use existing producers and surface facilities to avoid new drilling and infrastructure. Shorten Pilot Period: Choose wells with less spacing to reduce duration and operational costs. Least Production Disturbance: Select wells with poor production performance to minimize impact on overall production. The process includes: Selecting a suitable location. Preferring single completion wells. Choosing small well spacing patterns. Ranking pattern options. Analyzing the best pattern. Proposing well modifications. Conducting a sector model. Running sensitivity analysis. Optimizing parameters. Implementing the project

George’s point on offset wells is valuable insight. I once worked on a thermal project where we lost the front across a lease line. Suggest that where possible you should control all the offset acreage around your pilot. Gives opportunity to capture pilot results that may not be apparent in the pilot wells themselves.

One possibile fallacy in evaluating a steam pilot is not accounting for oil displaced outside the pilot area. Observation wells and reservoir simulation help in catching such behavior. Proving it requires offset drilling, but it is worth doing.

Some other ways to get started. -Research state of the art through technical databases such as the SPE’s OnePetro -Talk with other professionals who are subject matter experts (SME’s) -Develop a strategic plan -Do lab work first on cores

I once had the privilege of designing a pilot EOR program for a heavy oil reservoir in Northern Alberta. We gathered geological data and prepared reservoir property maps for the entire reservoir with special focus on the pilot area we thought was best. We figured an area with moderate structural relief and fairly uniform porosity and fluid density and viscosity would be ideal. We would then account for the broader variability in all these reservoir properties in the various simulated scenarios. This approach served us well, because at the end of the study, we had built a representative 3D pilot model that could interrogated in different ways and helped answer many operational questions that arose during the implementation of the pilot.

In most reservoirs there is a preferential steam, or CO2 flow path. Placing well patterns in respect to that direction makes a big difference in recovery and costs.

EL objetivo del piloto es conocer e iniciar una curva de conocimientos y lecciones aprendidas para más adelante hacer una expansión viable económica. Sin embargo asegurar el éxito es importante y contempla entonces asegurar la ventana de operación de la tecnología a aplicar, la simulación ajustada con un modelo de fluidos y reacciones representativas del fenómeno, realizar sensibilidades con diferentes escenarios, el volumen y clase de fluido o gases esperados y escoger bien el pozo o pozos en donde se vaya a realizar el piloto en conjunto con un análisis de riesgos.Además un layaut del sitio con los equipos e insumos buscando siempre optimizar el KPex y Opex y de esta manera decidir el mejor escenario.

The best way to address facility design is to apply scalability and modularity. Standardizing design early on helps in making necessary adjustments without redundancy and imposing unnecessary constraints. Keep the supply chain scale up at least a budget cycle ahead with options to cancel if necessary. The cost of scaling back is usually less than to scale up aggressively.

Training Oilefield personnel is very important in this stage. Keeping in mind that a pilot will become soon the internal standard for development, training and knowledge transfer needs to be addressed sooner than later to include smooth scaler up and developing safe practices and implementing lessons learned.

KPIs should include results from measurements that track or infer vertical movement of in-situ hydrocarbons and injected fluids above or below the target reservoir. Variations in localized permeability can (and likely will) lead to pressures higher than the various localized fracture pressures, in turn resulting in pathways into or beyond the intended sweep elevations. Such measurements could include minute changes in surface elevation at different locations across the extent of the pilot area.

For thermal methods that combine heat with volumetric displacement (such as with steam), it is critical to focus on the geomechanical changes that are occurring in real time during injection and production. Containment of injected steam within assumed boundaries can be very, very tricky when two or more of the magnitudes and directions of the principal stresses converge with each other. Technologies are available to monitor this in real time, and are typically mandatory when the reservoir of interest is shallow.

Keep in mind that each measurement is subject to errors and each analysis is subject for bias. Layering the initial analysis with different methods and surveillance sources helps avoiding starting development on wrong assumptions.