1. n. [Drilling Fluids]

A stable compound of sulfur that contains the S^–2 ion. Sulfides can be generated from soluble iron sulfide minerals or from sulfate-reducing bacteria. Active sulfides, which revert to H2S gas when acidified and consequently pose a potential danger, may be converted to inert sulfides by adding zinc oxide.

Reference: Garrett RL, Carlton LA and Denekas MO: "Methods for Field Monitoring of Oil-Based Drilling Fluids for Hydrogen Sulfide and Water Intrusions," SPE Drilling Engineering 3, no.3 (September 1988): 296-302.

See: barite,  buffered mud,  calcium hydroxide,  caustic extraction test,  Dräger tube,  Garrett Gas Train,  hydrogen sulfide,  iron oxide,  iron sulfide,  lime mud,  neutralization,  OSHA,  pyrrhotite,  scavenger,  sour gas,  stress corrosion cracking,  sulfide,  sulfide scavenger,  zinc basic carbonate,  zinc bromide,  zinc carbonate,  zinc chloride