Enhanced oil recovery (EOR) or tertiary recovery, is the process of extracting oil from an oil field or a reserve that would otherwise be inaccessible using conventional production technology. EOR techniques extract greater volumes from a reserve by altering the oil’s physical properties (i.e. viscosity/density).
There are three primary processes of tertiary or EOR extraction:
- Thermal recovery
- Gas injection
- Chemical/Solvent injection
Projected to reach $89.22 billion by 2025, the enhanced oil recovery market is rapidly growing and requires experienced facility engineering designs to improve recovery methods.
Vista has successfully engineered cutting-edge EOR facilities. Our focus on fit-for-purpose engineering designs and a data-centric approach to project execution are of great value in the EOR market, where cost efficiency is of great importance.
Alkaline Surfactant Polymer (ASP) Flooding
Alkaline Surfactant Polymer (ASP) flooding is an EOR method that involves injecting alkaline chemicals, surfactants, and polymers into the reservoir to decrease surface tension and enhance oil flow.
A diluent is typically blended with bitumen extracted in an EOR facility before the bitumen is transported in a pipeline. Once the bitumen is delivered to its final destination (typically a refinery or upgrading facility), the diluent may be extracted from the bitumen and re-used for blending purposes.
Miscible flooding involves injecting miscible gases into a reservoir to extract oil. Gases, like nitrogen and carbon oxides, as well as hydrocarbon gases, such as butane and propane, are typically used in the process. The process reduces the viscosity and density of the oil, thus making it easier for it to flow from the reservoir to the surface.
Water flooding is another EOR method which involves injecting water to expand the oil-production rate of reservoirs. Water injection increases reservoir pressure and helps move oil towards the production well.
Polymer Blending and Flooding
The Polymer Blending EOR technique mixes dry polymer with water in a reaction tank to create a concentrated polymer solution that is then sent to a dilution tank for ageing, before being sent to the injection well.
Polymer Flooding is an EOR technique that increases water viscosity to reduce the ratio of water to oil, using soluble polymers. The high viscosity polymer solution is more effective than pure water at sweeping oil from the reservoir to the producing well. The two polymers typically used for the process are:
- Partially hydrolyzed polyacrylamide