H.sub.2 S abatement with stabilized chelates in geothermal drilling

摘要

H.sub.2 S abatement in geothermal drilling operations (e.g. drilling, flow testing and reworking) with a ferric aminocarboxylic acid chelating solution containing a stabilizer and an optional cationic polyelectrolyte catalyst which is injected in the blooie line of the well upstream of the separator. The stabilizer is a hydroxyl radical scavenger such as iodide, nitrite, amino acid, aliphatic aldehyde, sugar, ascorbate, formate and/or aryl sulfonic acid, and inhibits degradation the ferric aminocarboxylic acid complex.