A kinetic study on bacterial sulfate reduction

Abstract

The activity of anaerobic sulfate reduction was studied using sulfate-reducing bacteria isolated from the water produced from a Brazilian oil reservoir. The effects of the initial sulfate concentration on the anaerobic sulfate reduction and sulfide generation kinetics were investigated. The redox potential, the biomass solution content, and the sulfate and the sulfide solution content were measured. The results indicate that the sulfate conversion and the sulfide generation are both first-order processes for the initial sulfate concentration of 823, 1,282, and 1,790 mg/L. The results for the kinetic constants for the sulfate conversion indicate an inhibition with the enhancement of the initial sulfate solution content. The kinetic constants for the sulfide generation indicate that this reaction is almost independent of the initial sulfate solution content due to the presence of at least two in-series processes that are faster than the microbial conversion of the sulfate. The kinetic test using the water from an onshore oil field, with an initial sulfide content of 228 mg/L and sulfate content of 947 mg/L, shows a sulfate conversion of 50 % in 528 h. The kinetic modeling for the net content of sulfate and sulfide indicates that the sulfate conversion is slower for this water than for the deionized water tests; however, the sulfide formation has almost the same conversion velocity. The reactions are first order in both cases.

Improved method for enumerating sulfate-reducing bacteria using optical density

“…A mixed culture of sulfate reducing bacteria was enriched from the produced water from the oil fields of the Recôncavo Baiano basin, Brazil and used as an inoculum. This enrichment is dominated by bacteria of the species Desulfovibrio vulgaris [1] , [2] , [3] .…”

Hydrogeochemical Modeling to Identify Potential Risks of Underground Hydrogen Storage in Depleted Gas Fields

“…The energy gained from sulfate reduction is used by the SRB for cell growth [14]. SRB prefer temperatures around 38 • C [15] and near-neutral pH conditions [14], but are active even at extreme habitat conditions such as at great depths and temperatures, ranging from 0 • C to 60-80 • C [16][17][18] and in some cases up to 110 • C [19]. SRB activity was observed, for example, in hydrocarbon reservoirs [18] and in the underground storage of town gas [20].…”

Hydrogen sulfide (H2S) emission control by aerobic sulfate reduction in landfill

“…During the stabilization process, sulfate is converted into other sulfur forms by anaerobes (e.g., SRB) or assimilated to form organic containing sulfur (OCS)20. However, it was unexpected that the sulfate content in our anaerobic landfills (AL and RAL) did not diminish.…”