Proactive Management of H2S Levels in a Mildly Sour Gas Field Through Production System Optimization: Case Study From Central Luconia Province, Malaysia

Abstract

High H2S issue was investigated in Field B shortly after production, with quite a variation on the measured H2S readings. The initial opinion was it might be related to the measuring methodology, as no evidence to suggest that the H2S level would increase over time from the reservoir point of view. To verify this, a full sampling program was conducted, consisting of onsite sampling and laboratory analysis. This includes stain tubes measurement, online gas chromatograph, H2S analyzer and UOP method. The H2S isotope analysis was also conducted to determine the H2S source and its future behavior in the reservoir. This paper serves as lesson learnt and best practices in H2S management from subsurface to facilities unified approach, highlighting the importance of proper data acquisition, with focus on contaminants. Indeed, H2S is a contaminant found widely in oil and gas industry and can be a limiting factor to development or hinder production if it is not appropriately characterized during exploration, appraisal and early stage of production.