Water Alternating Gas (WAG) is a proven method used in Enhanced Oil Recovery (EOR) to increase the amount of extractable oil from a reservoir. The process involves injecting alternating slugs of water and gas (typically CO₂) into the reservoir.
- Water injection maintains reservoir pressure and helps sweep oil toward the production well.
- Gas injection reduces oil viscosity and improves mobility for better extraction.
By cycling between water and gas, WAG provides improved sweep efficiency, pressure maintenance, and oil displacement—leading to significantly increased recovery rates compared to traditional methods.
Why Hydroplex Valves Are Used in WAG Systems
Hydroplex throttling valves—particularly the HCY model—are well-suited to the challenges of WAG systems due to their robust construction, reliability, and field-ready performance features:
- Corrosion Resistance: Stainless steel body resists corrosion from CO₂ and water—two aggressive elements common in WAG environments.
- Explosive Decompression Prevention: PC-cured Buna N elastomer seals are designed to resist explosive decompression, increasing safety and durability.
- Cavitation and Velocity Protection: A Stellite wear sleeve protects against mechanical erosion caused by cavitation during water injection, enhancing valve longevity.
- Modular Design: The body’s modular design enables easy replacement of the downstream hub, allowing the valve’s service life to match that of the field.
Valve Sizing Note
Correct valve sizing is critical to WAG system performance.
Because WAG cycles between gas and liquid phases, the injection valve must be able to manage both effectively:
- During the gas phase, the valve needs to accommodate high flow rates and pressures to inject gas efficiently into the reservoir.
- During the liquid phase, it must handle large water volumes with minimal pressure drop to ensure optimal oil sweep.
The valve trim size must meet the demands of both phases to ensure smooth and efficient system operation. Proper sizing considers:
- Flow rates
- Pressure conditions
- Fluid properties
- Injection system specifications
Accurate sizing ensures long-term reliability and performance in WAG-enhanced recovery operations.
Ready to Upgrade?
Improve your WAG system performance with a Hydroplex throttling valve. Contact our team today for technical specs, installation support, or to request a quote.