Reservoir Souring – Control Using Biocides
A three year research programme, conducted jointly by Oil Plus and the University of Exeter, has concentrated on the survival, sulphide production and biocide control of a range of sulphate-reducing bacteria (SRB) which are able to grow at temperatures above 60˚C. These are the so-called thermophilic SRB (tSRB), one of the types now believed to be responsible for oilfield reservoir souring.
Novel laboratory techniques, including the flowing of bacteria through real rock cores, have shown that these bacteria can be controlled using biocides at conventional dose rates although, as was to be expected, some active ingredients were more effective than others. A trial in one of the sponsors’ fields using one of the effective compounds confirmed the laboratory data and reduced the sulphide souring of the treated areas of the reservoir both significantly and rapidly.