Sulfate-Reducing Bacteria Release Barium and Radium from Naturally Occurring Radioactive Material in Oil-Field Barite

Abstract

Scale and sludge deposits formed during oil production can contain elevated levels of Ra, often coprecipitated with barium sulfate (barite). The potential for sulfate-reducing bacteria to release 226 Ra and Ba (a Ra analog) from oil-eld barite was evaluated. The concentration of dissolved Ba increased when samples containing pipe scale, tank sludge, or oil-eld brine pond sediment were incubated with sulfate-reducing bacteria Desulfovibrio sp., Str LZK1, isolated from an oil-eld brine pond. However, Ba release was not stoichiometric with sul de production in oil-eld samples, and <0.1% of the Ba was released. Potential for the release of 226 Ra was demonstrated, and the 226 Ra release associated with sulfate-reducing activity was predictable from the amount of Ba released. As with Ba, only a fraction of the 226 Ra expected from the amount of sul de produced was released, and most of the Ra remained associated with the solid material.Oil and natural gas reservoirs commonly contain large quantities of saline water, often including dissolved Ba C2 and Ra C2 . When water is produced along with oil and gas, decreases in temperature, pressure, and salinity result in formation of scale (adherent precipitate) in pipes and equipment (Wilson and Scott 1992). The level of radioactivity in pipe scale and tank sludge formed during petroleum production is often elevated (4-400 Bq/g) due to the incorporation of 226;228 Ra in the scale (Wilson and Scott 1992). The U.S. Environmental

Organic and inorganic composition and microbiology of produced waters from Pennsylvania shale gas wells

“…Methanogens are scored as positive for activity based on production of >10 ppm methane in the headspace. (2015) xxx-xxx addition, microbial dissolution of barite could contribute to increases in Ba concentrations in PW as previously seen for barite in oil fields, uranium mill tailings, and sewage sludge (Landa et al, 1986;Baldi et al, 1996;Phillips et al, 2001). However, we cannot exclude the possibility that the enriched H 2 S-producing bacteria were fermenting cysteine to H 2 S, an unusual pathway metabolism carried out by the sulfate-reducer Desulfovibrio desulfuricans (Forsberg, 1980).…”

Cr(VI) Reduction by Sulfidogenic and Nonsulfidogenic Microbial Consortia

“…sequence. The other SRB was 99% related to the Desulfovibrio strain LZK1, found in naturally occurring radioactive material (27). Some bacterial species were present in two consortia (a Pantoea sp., a Shewanella sp., and the uncultured bacterium DCE-25, a Spirochaeta sp.).…”

Relationships between radium and radon occurrence and hydrochemistry in fresh groundwater from fractured crystalline rocks, North Carolina (USA)

“…Radium mobility or adsorption effectiveness is understood to vary with chemical parameters including pH (Cecil et al, 1987;Dickson and Herczeg, 1992;Bolton, 2000;Szabo et al, 2005), salinity (Kraemer and Reid, 1984;Sturchio et al, 2001;Wood et al, 2004), reduced conditions (Szabo and Zapecza, 1987;Herczeg et al, 1988), supersaturation with respect to barite (Gilkeson et al, 1984;Grundl and Cape, 2006), microbial sulfate reduction affecting barite stability (Phillips et al, 2001;Martin et al, 2003), and microbial Fe oxide reduction (Landa et al, 1991). Ra adsorption is a rapid influence in freshwater at nearneutral pH (Krishnaswami et al, 1982), but the effects of redox processes and relatively low ion concentrations on adsorption and desorption are not well constrained in existing field investigations.…”