Cyclic Steam Injection (CSI) pilot design

Overview

Most E&P operators are challenged with finding cost-effective solutions for improving reservoir recovery factors. Well-planned CSI can provide significant benefits, such as increased production and recovery factor. Additionally, the earlier an operator applies the method, the more likely they are to gain positive economic results.

Field pilot can provide valuable knowledge on the feasibility and potential of CSI, reduce the full field deployment risks, and increase the operator’s knowledge about the process. However, many field pilots take much longer than needed and are unsuccessful due to cost overruns, lack of clear results, inappropriate monitoring, disregard of important operational aspects, and lack of expertise.

The Halliburton method is a disciplined approach to CSI optimization that can determine the best scenario before beginning a pilot, reduce cost overruns due to trial and error, and reduce the time to positive net present value. The CSI method can offer high final oil recoveries, with records indicating up to 65% of the OOIP when proper reservoirs are chosen, sound pilot design, and execution excellence. Halliburton can achieve this by acting as an integrated service provider with complete oversight of the entire process from visualization to evaluation of the pilot. Our approach offers the possibility of successfully executing a pilot before cost-effectively extending the technique.

Case study

A multidisciplinary NOC-Halliburton team developed a pilot design based on results from the integrated reservoir study. The diagnosis study shows a steam-to-oil ratio (SOR) of 0.33, which increased cost efficiency by about 9 times compared to the average

Hot oil (first cycle of steam injection) was 11 times higher than cold, which is 3 times higher than the worldwide average.

Applications

CSI is ideal for viscous oil reservoirs with good horizontal permeability and medium thickness net pay. Non-fractured sandstones are preferred, but deployment in carbonate is also possible.

Typically, CSI is implemented right after the primary exploitation phase and in some cases as a previous step for steam flooding.

Cyclic steam injection pilot: The five-phase approach

Halliburton offers a tailored solution at any stage of your field’s life using a five-phase approach. The main advantage of the approach is that the operator can start the process at their convenience.

The above phases can provide clients:

1. Project kickoff and data assessment ensure a comprehensive reservoir review to evaluate performance and establish the risks for CSI
2. Rock-Fluids analysis, detailed core laboratory tests, and simulation input data increase the pilot’s probability of success
3. Base case and optimized case forecasts for the pilot, taking into account reservoir modeling and simulation, nodal analysis, and surface requirements
4. Analysis of the impact of operational and technical uncertainties on the success of the pilot program
5. First-cut economic analysis and forecast of the full-field implementation of the pilot design recommendations using stochastic techniques and smart optimization algorithms

To optimize conditions for the pilot, the operator addresses main concerns such as the length of injection cycle, the amount of steam to be injected, the water source, the conditions for the water treatment plant, and building and operating restrictions.

Deliverables include a representative pilot area, well integrity analysis, rock and fluids characterization, a suitable laboratory work program to evaluate changes in oil saturation during steam injection, numerical simulation, facility design, construction, and operation, among others.

Features of the Halliburton approach

• Detailed laboratory analysis for improved simulation and estimation of production potential
• Designed for quicker production response from producer wells, improving the pilot program and full program economic performance
• Stochastic analysis of risk uncertainty and optimized design using smart algorithms

The Halliburton approach can provide the following benefits

• Offers early determination of the potential effectiveness of development scenarios through the semi-quantitative Chance of Success (COS) methodology
• Maximizes available surface and subsurface infrastructure
• Reduces the level of risk at commercial application by addressing surface/subsurface operational parameters that can be unknown
• Integrates the process at any stage during the life of the reservoir and supports the best operator workflow to plan and execute the pilot
• Provides accountability through all phases of the process
• Can provide the proper number of cycles, field operating conditions, steam quality, or specifications for designing surface facilities
• Offers the possibility of acquiring an integrated view of the process when implementing the approach

Typical project schedule

The estimated project duration, including execution and monitoring of a pilot, is around 24 months. The start of the commercialization phase relies on the pilot’s response.

Technologies

• Smart algorithms to optimize crude oil recovery strategies by looking at different uncertainty variables (k, porosity, thickness, oil price, operation costs) and decision variables (injection rate, time, soak time, steam quality). Our stochastic machine (DMS™) couples with analytical and numerical simulation models from different tools.
• DecisionSpace® well planning and WellCat™ software can assist in modeling multiple steam-injection scenarios, handling superheated steam or saturated steam with a given quality.
• FiberWatch® service is a distributed temperature sensing technology to monitor the steam profile.
• Chemical Management Services offer solutions to handle flow assurance issues by monitoring the response from the pilot.

In summary, Halliburton’s five-phase approach can provide a structured outlook, including uncertainty, economics, and risks for the pilot and first-cut economic forecasts for full field implementation.