Primary tabs
Oxygen Scavenger OxyGuard S
Powerful concentrated corrosion inhibitor acts as oxygen scavengers used to effectively remove dissolved OXYGEN
This is most common oxygen treatment as a scavengers used to effectively remove dissolved OXYGEN from your feedwater. By the presence of dissolved oxygen in system, corrosion and pitting caused on metal surface. Removes dissolved oxygen, By acting as an oxygen scavenger.
A fast-acting, catalyzed sodium sulphite (Na₂SO₃) oxygen scavenger for low- and medium-pressure boiler systems. The product reacts stoichiometrically with dissolved oxygen to prevent corrosion in boilers, feed lines, and condensate systems by converting oxygen to inert sulfate.
- Oxygen removal in low/medium-pressure boilers (typically up to ~65 bar; usage above this pressure is uncommon due to potential sulfate/solids carryover).
- Hot standby protection to prevent pitting during idle periods i.e. Oilfield Application.
- Feedwater & deaerator outlets where residual O₂ must be suppressed rapidly.
Reaction (overall):
Na₂SO₃ + ½ O₂ → Na₂SO₄
Catalyst accelerates the reaction at lower temperatures and shorter residence times (e.g., in deaerator outlets and feedwater lines)
- Deaerator outlet O₂: ≤ 7–10 ppb (if DA present)
- Sulfite residual in boiler water:
- Normal operation: 20–40 mg/L as Na₂SO₃
- High risk / wet lay-up: 60–100 mg/L as Na₂SO₃
- pH (feedwater/boiler): follow your internal treatment program (commonly FW pH 8.5–9.2; boiler water pH 10.5–11.5 depending on pressure).
- Preferably deaerator storage section or feedwater line upstream of economizer to ensure complete O₂ removal before the boiler.
Example Dose Calculation
Feedwater DO = 0.10 mg/L (100 ppb) at 20 m³/h.
Stoichiometric Na₂SO₃ = 0.10 × 7.88 = 0.788 mg/L.
With 1.3× safety factor → ~1.0 mg/L Na₂SO₃.
At 20 m³/h → 20 g/h Na₂SO₃ (as pure).
Using 38% liquid: 20 / 0.38 ≈ 52.6 g/h (~40 mL/h) (SG 1.32 ⇒ ~30 mL/h by mass; verify on site).
Fine-tune to maintain target sulfite residual in boiler.
- Rapid kinetics with catalyst—effective even at moderate temperatures.
- Reliable corrosion protection of pre-boiler & boiler circuits.
- Cost-effective vs. volatile scavengers for LP/MP systems.
- Easy control by simple sulfite residual testing.
- Compatible with most phosphate/polymer internal treatments.
| Property | Specification |
|---|---|
| Appearance | Clear to pale straw liquid |
| Specific gravity @ 25 °C | ~1.30 – 1.34 (depends on strength) |
| pH (neat) | 8.5 – 10.5 (stabilized alkaline) |
| Odor | Faint sulfurous |
| Freeze point | < 0 °C (varies with strength) |
| Solubility | Completely miscible with water |
Control test methods:
- Residual sulfite by iodometric titration (express as mg/L Na₂SO₃).
- Dissolved oxygen by luminescent/optical or membrane DO analyzer at DA outlet.
- Start with calculated stoichiometric dose + safety factor based on measured DO.
- Adjust pump to maintain target sulfite residual in the boiler drum.
- Increase dose for intermittent operation, cold feeds, or high leakage air into DA.
- For wet lay-up, raise sulfite residual to upper range and circulate periodically.
- Compatible with phosphates, chelants (as per program limits), and dispersant polymers used for scale/sludge control.
- Avoid co-feeding with oxidizing biocides (e.g., chlorine) as they will consume sulfite.
- Downstream of RO systems, sodium bisulfite is typically preferred for dechlorination; this product is not intended as an RO dechlorinator.