Primary Applications

• Oxygen Scavenging & Corrosion Control: It chemically reacts with dissolved oxygen in water-based systems to form sodium sulfate and water. This process is vital for:
  • Drilling Fluids: Protecting wellbore pipes and drill bits from oxygen-induced pitting corrosion.
  • Pipelines & Storage Tanks: Preventing internal degradation of metal surfaces caused by dissolved oxygen in produced fluids.
  • Waterflooding: Removing oxygen from injection water used to displace residual oil, which preserves the integrity of injection wells.
• H2S Mitigation: By removing dissolved oxygen, it helps stop the chemical reaction between oxygen and sulfides that can lead to the formation of highly toxic and corrosive hydrogen sulfide (H2S) gas.
• Boiler Water Treatment: In refineries and production facilities, it is used in low-to-medium pressure steam boilers to prevent pitting corrosion of boiler tubes.
• Specialized Oilfield Uses:
  • Shale Inhibition: Used in some drilling fluid systems to prevent the swelling and dispersion of shale formations.
  • Scale Prevention: Helps control the concentration of certain ions in produced fluids to mitigate mineral scale buildup.
  • Produced Water Treatment: Employed in treating oilfield wastewater to reduce heavy metals and neutralize aggressive oxidizing agents. 

Operational Details

• Concentration: The 38-42% aqueous solution is an industry-standard concentration because it is easier to dose accurately than sulfur dioxide gas and has a lower corrosion potential.
• Catalysis: In colder environments or systems without deaerators, catalyzed sodium bisulfite (often using cobalt salts) is used to ensure rapid oxygen removal at ambient temperatures.
• Dosage: Typical industrial dosing ranges from 0.1% to 1% v/v, depending on the specific oxygen levels and flow rates of the system.