Impact of Hydrogen Sulfide Scavenger Residuals on the Fluorescence Behaviour of OiW Discharges from Gas-Condensate Production

Abstract

The oil-in-water (OiW) contaminants in produced water discharges arising from offshore oil and gas production systems are required by global regulatory bodies to be monitored in order to limit the environmental impacts of such releases. The level of these contaminants is commonly measured using online analyzers that utilize UV fluorescence to target the luminescent properties of OiW components. It is known that the nature and variability of the fluorophores in the OiW fractions may influence the response of these type of analyzers. In particular these readings can also be affected by chemical residuals used in oil and gas treatment, that may also be present in the produced water. This study reports on the impact of the reaction products of a monoethanolamine based hydrogen sulfide scavenger, used in gas treatment to remove hydrogen sulfide (H2S), on the fluorescence behavior of OiW discharges, and its implications on the OiW reporting levels that may be expected from deep-UV and near-UV based analyzers.