Reactive Transport Model of Sulfur Cycling as Impacted by Perchlorate and Nitrate Treatments.
Microbial souring in oil reservoirs produces toxic, corrosive hydrogen sulfide through microbial sulfate reduction, often accompanying (sea)water flooding during secondary oil recovery. With data from column experiments as constraints, we developed the first reactive-transport model of a new candidate inhibitor, perchlorate, and compared it with the commonly used inhibitor, nitrate. Our model provided a good fit to the data, which suggest that perchlorate is more effective than nitrate on a per mole of inhibitor basis. Critically, we used our model to gain insight into the underlying competing mechanisms controlling the action of each inhibitor. This analysis suggested that competition by heterotrophic perchlorate reducers and direct inhibition by nitrite produced from heterotrophic nitrate reduction were the most important mechanisms for the perchlorate and nitrate treatments, respectively, in the modeled column experiments. This work demonstrates modeling to be a powerful tool for increasing and testing our understanding of reservoir-souring generation, prevention, and remediation processes, allowing us to incorporate insights derived from laboratory experiments into a framework that can potentially be used to assess risk and design optimal treatment schemes.
Lawrence Berkeley National Laboratory , Berkeley, California, 94720 United States.
Yiwei
Y
Cheng
Lawrence Berkeley National Laboratory , Berkeley, California, 94720 United States.
Christopher G
CG
Hubbard
Pennsylvania State University , University Park, Pennsylvania, 16802 United States.
Li
L
Li
Lawrence Berkeley National Laboratory , Berkeley, California, 94720 United States.
Nicholas
N
Bouskill
Lawrence Berkeley National Laboratory , Berkeley, California, 94720 United States.
Sergi
S
Molins
Lawrence Berkeley National Laboratory , Berkeley, California, 94720 United States.
Liange
L
Zheng
Lawrence Berkeley National Laboratory , Berkeley, California, 94720 United States.
Eric
E
Sonnenthal
Lawrence Berkeley National Laboratory , Berkeley, California, 94720 United States.
Mark E
ME
Conrad
Department of Plant and Microbial Biology, University of California , Berkeley, California, 94720 United States.
Anna
A
Engelbrektson
Department of Plant and Microbial Biology, University of California , Berkeley, California, 94720 United States.
John D
JD
Coates
Lawrence Berkeley National Laboratory , Berkeley, California, 94720 United States.
Jonathan B
JB
Ajo-Franklin
D009566:Nitrates / Q000494:pharmacology; D009573:Nitrites; D010472:Perchlorates; D013455:Sulfur; D016999:Sulfur-Reducing Bacteria / Q000187:drug effects
D009566:Nitrates; D009573:Nitrites; D010472:Perchlorates; D013455:Sulfur