Polymer flooding projects are more and more challenging and require a full set of integrated expertise, from chemistry to system engineering. In order to design such a project, a wide variety of variables must be considered:

• Selection of monomer
• Polymer structure
• Polymer dissolution
• Injection system
• Water pre-treatment
• Supply chain

SNF provides the full range of expertise required to support the need of EOR as evidenced by a recent large-scale multi-year contract for the engineering and construction of a polymer flooding project in the Marmul field in the south of Oman.
SNF can provide:

• Reservoir engineering
• Monomer integration
• Polymer selection design
• Polymer manufacturing
• Polymer storage and dissolution equipment
• Injection equipment
• Engineering and system design
• Training, Start-Up and Commissioning

Engineering Services

To ensure a proper injection in the reservoir, it is important for the polymer to be dissolved properly, for the equipment to be compatible with the polymer and for the solution to be handled properly and injected on continuous basis.
In order to optimize the different phases of a project, SNF proposes a wide range of engineering services and polymer flooding equipment to customers all around the world, thanks to dedicated EOR Engineering teams.

Conceptual studies

During preliminary phases of polymer flooding project, SNF can develop conceptual studies of facilities to evaluate the technical feasibility, CAPEX budget and assess flooding project risks (facilities/logistics aspects). Different technical options for polymer storage, dissolution and injection are studied and compared: main process principles are described, logistics issues are highlighted and basic cost and high level planning are proposed. Typically, the following deliverables are provided by SNF at the end of the study:


a. Process description
b. Supply chain description
c. Process flow diagram (PFD), for polymer storage, preparation and injection
d. Preliminary mass balance
e. Preliminary equipment list
f. Estimated electrical power consumption
g. Preliminary general layout and land requirement
h. Basic operating & control philosophy
i. Preliminary material selection report
j. Level 2 schedule for polymer facilities
k. Identification of the long lead items
l. Proposed SNF vendor list
m. Cost estimation of facilities (±30%)
n. Comparison of different options and SNF recommended solution

Injectivity test

Also during the preliminary phase of a project, SNF is able to provide a very specific service to oil companies: polymer injectivity test. The main interest of this injectivity test will be to establish and validate the flow rate and pressure at which the polymer solution can be pumped into the reservoir without fracturing the formation.

Pilot and full field equipment

As soon as the polymer selection and the injection parameters have been validated, the next step of the polymer flooding projects could go through a continuous pilot injection or directly to a full field development. This is really the core business of SNF EOR engineering department, which can propose either skids mounted units (for pilot or small size full field projects) built in SNF partners’ workshops or field erected plant (for large pilot or full field projects), where typically equipment are sent and assembled at site.

Water Treatment

When dealing with water treatment, two points have to be tackled. The first one concerns the quality of the dissolution or injection water. The presence of contaminants such as oxygen, H2S and iron has to be limited in order to avoid the degradation of the polymer solution. Sometimes the water has to be treated to remove the excess of iron or oxygen.
The second point concerns the treatment of the produced water. At the pilot stage (with only few injecting wells), there is no need to assess the effect of the back-produced polymer because of the dilution effect in the reservoir and within the surface facilities. When dealing with a full field, studies can be performed to find out the best treatments to cut the remaining polymer backbones and therefore decrease the water viscosity (preferentially after the Oil/Water separation not to affect the quality of the crude). Among the possible treatments, chemical and mechanical are along the most used.