Bacterially Induced Calcium Carbonate Precipitation and Strontium Coprecipitation in a Porous Media Flow System

Ellen G. Lauchnor, Logan N. Schultz, Steven Bugni, Andrew Charles Mitchell, Alfred B. Cunningham, Robin Gerlach

Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

104 Dyfyniadau(SciVal)

Crynodeb

Strontium-90 is a principal radionuclide contaminant in the subsurface at several Department of Energy sites in the Western U.S., causing a threat to groundwater quality in areas such as Hanford, WA. In this work, we used laboratory-scale porous media flow cells to examine a potential remediation strategy employing coprecipitation of strontium in carbonate minerals. CaCO3 precipitation and strontium coprecipitation were induced via ureolysis by Sporosarcina pasteurii in two-dimensional porous media reactors. An injection strategy using pulsed injection of calcium mineralization medium was tested against a continuous injection strategy. The pulsed injection strategy involved periods of lowered calcite saturation index combined with short high fluid velocity flow periods of calcium mineralization medium followed by stagnation (no-flow) periods to promote homogeneous CaCO3 precipitation. By alternating the addition of mineralization and growth media the pulsed strategy promoted CaCO3 precipitation while sustaining the ureolytic culture over time. Both injection strategies achieved ureolysis with subsequent CaCO3 precipitation and strontium coprecipitation. The pulsed injection strategy precipitated 71–85% of calcium and 59% of strontium, while the continuous injection was less efficient and precipitated 61% of calcium and 56% of strontium. Over the 60 day operation of the pulsed reactors, ureolysis was continually observed, suggesting that the balance between growth and precipitation phases allowed for continued cell viability. Our results support the pulsed injection strategy as a viable option for ureolysis-induced strontium coprecipitation because it may reduce the likelihood of injection well accumulation caused by localized mineral plugging while Sr coprecipitation efficiency is maintained in field-scale applications.
Iaith wreiddiolSaesneg
Tudalennau (o-i)1557–1564
Nifer y tudalennau8
CyfnodolynEnvironmental Science & Technology
Cyfrol47
Rhif cyhoeddi3
Dynodwyr Gwrthrych Digidol (DOIs)
StatwsCyhoeddwyd - 02 Ion 2013

Ôl bys

Gweld gwybodaeth am bynciau ymchwil 'Bacterially Induced Calcium Carbonate Precipitation and Strontium Coprecipitation in a Porous Media Flow System'. Gyda’i gilydd, maen nhw’n ffurfio ôl bys unigryw.

Dyfynnu hyn