SulfaGuard SG-18

Neutral pH H2S Scavenger Eliminates Corrosion Risk, Foaming and Downstream Risk

A Northern Louisiana midstream operator running high-water-cut, wet-gas pipelines with an amine plant downstream evaluated Coastal Chemical’s SG-18 against the incumbent SG-1 (glyoxal based). SG-1 delivered acceptable H2S removal but introduced chronic low-pH corrosion. Field trials and laboratory breakthrough testing confirmed SG-18 as the superior, lower-cost solution — removing H2S faster, at a neutral pH, with no solids, no foaming, and measurable corrosion and scale inhibition built in.

CHALLENGES

• High-water-cut wet-gas pipeline (high-velocity, multiphase flow)
• SG-1 Scavenger (pH ~2) under current operating conditions shows a potential corrosion risk of ~10 mpy on pipeline steel.
• Plugging incidents when line dried — glyoxal saturation issues
• Triazine-based chemistries have exhibited foaming episodes in the amine plant, increasing filter/coalescer maintenance.
• Operator seeking single-product H2S removal + corrosion control

SOLUTION

An isolated field trial of SG-18 was conducted on a gas well application in Northern Louisiana, enabling a direct performance comparison against SG-1 under equivalent operating conditions. The evaluation demonstrated enhanced treatment efficiency and operational advantages in a wet, high water-cut, multiphase system.

Key findings include:

• Injection Performance: Continuous injection into the gas stream achieved high contact efficiency within the multiphase flow regime, with no observable dispersion or phase separation issues.)
• Scavenging Kinetics: Independent breakthrough testing at 15-minute retention time confirmed that SG-18 exhibits faster reaction kinetics and higher H₂S removal efficiency compared to SG-1 at equivalent dosage rates.
• Residual Monitoring: Implementation of SI-tagged inhibitor technology allowed precise quantification of residual chemical in the pipeline, enabling proactive re-treatment scheduling and minimizing unplanned well interventions. Triazine-based chemistries have exhibited foaming episodes in the amine plant, increasing filter/coalescer maintenance.
• Multifunctional Performance: SG-18 demonstrated integrated functionality by simultaneously providing H₂S scavenging, corrosion inhibition, and scale control, effectively consolidating multiple chemical programs into a single-product solution

RESULTS

• H2S removal equivalent or better vs SG-1 at comparable dose rate
• Corrosion rate dropped from ~10 mpy to <1 mpy — asset life extended
• Zero foaming or plugging events during 1+ month trial
• Clean filters, coalescers, amine plant — no formaldehyde carry-over
• Lower net cost per gallon H2S removed; no extra inhibitor needed