Mitigation strategies for sealing high permeability regions in cap rocks, such as fractures or improperly abandoned wells, are important considerations the long term security of geologically stored carbon dioxide (CO2). Sealing technologies using low-viscosity fluids advantageous this context since they potentially reduce necessary injection pressures and increase radius influence around wells. Using aqueous solutions suspensions that can effectively promote microbially induced mineral...

Strontium-90 is a principal radionuclide contaminant in the subsurface at several Department of Energy sites Western U.S., causing threat to groundwater quality areas such as Hanford, WA. In this work, we used laboratory-scale porous media flow cells examine potential remediation strategy employing coprecipitation strontium carbonate minerals. CaCO(3) precipitation and were induced via ureolysis by Sporosarcina pasteurii two-dimensional reactors. An injection using pulsed calcium...

Ureolysis drives microbially induced calcium carbonate precipitation (MICP). MICP models typically employ simplified urea hydrolysis kinetics that do not account for cell density, pH effect or product inhibition. Here, ureolysis rate studies with whole cells of Sporosarcina pasteurii aimed to determine the relationship between and concentrations (i) urea, (ii) cells, (iii) NH4+ (iv) (H(+) activity).Batch experiments were performed suspended S. one parameter was varied in each set...

ABSTRACT An experimental model that mimicked the structure and characteristics of in vivo biofilm infections, such as those occurring lung or dermal wounds where no biomaterial surface is present, was developed. In these microbial forms cell aggregates interspersed a layer mucus host matrix material. This modeled by filling glass capillary tubes with an agarose gel had been seeded Staphylococcus aureus bacteria then incubating medium for up to 30 h. Confocal microscopy showed formed discrete...

Abstract The model for microbially induced calcite precipitation (MICP) published by Ebigbo et al. (2012) has been improved based on new insights obtained from experiments and calibration. challenge in constructing a predictive permeability reduction the underground with MICP is quantification of complex interaction between flow, transport, biofilm growth, reaction kinetics. New data Lauchnor (2015) whole‐cell ureolysis kinetics batch were incorporated into model, which allowed more precise...

Research on microbially induced calcite precipitation (MICP) is reported. MICP may serve to reduce near-wellbore permeability, CO2– related corrosion, and lower the risk of unwanted migration CO2 or other fluids. research lab scale has demonstrated ability seal sandstone cores using injection strategies engineered control precipitation. Experimentation was also aimed at transitioning for field implementation. evaluated in a hydraulically fractured formation Walker County, Alabama well. The...

Recent scientific investigations have shed light on the ecological importance and physiological complexity of subaerial biofilms (SABs) inhabiting lithic surfaces. In field sustainable cultural heritage (CH) preservation, mechanistic approaches aimed at investigation spatiotemporal patterns interactions between biofilm, stone, atmosphere are outstanding importance. However, these proven difficult to explore with experiments due inaccessibility samples, ecosystem under temporal resolution...

Abstract Methods of mitigating leakage or re‐plugging abandoned wells before exposure to CO 2 are high potential interest prevent injected for geologic carbon sequestration in depleted oil and gas reservoirs where large numbers often present. While resistant cements ultrafine being developed, technologies that can be delivered via low viscosity fluids could have significant advantages including the ability plug small aperture leaks such as fractures delamination interfaces. Additionally...

Infection stones, which comprise approximately 15% of all urinary tract are induced by infection with urease-positive pathogens. The bacteria in the stone matrix present significant treatment impediments compared to metabolic kidney stones. While much is known about how composition regulates formation, there a general lack knowledge factors regulate rate formation. Unfortunately more in-depth research into stones limited suitable models for real-time study bacterial biofilm formation and...

Abstract Attachment of bacteria in porous media is a complex mixture processes resulting the transfer and immobilization suspended cells onto solid surface within medium. Quantifying rate attachment difficult due to many simultaneous possibly involved attachment, including straining, sorption, sedimentation, difficulties measuring metabolically active attached media. Preliminary experiments confirmed difficulty associated with Sporosarcina pasteurii However, key process applications...

Abstract Selenium is a widespread contaminant released by industrial activities such as coal combustion. In selenium-contaminated groundwater, native microbial communities commonly have the capability of reducing toxic oxyanions selenate and selenite to insoluble elemental selenium. The impact local hydrogeography on selenium reduction was tested constructing laboratory microcosms using biofilm groundwater collected from four monitoring wells screened in three distinct stratigraphic units...

Abstract Pure culture biofilms of the ammonia‐oxidizing bacterium Nitrosomonas europaea were grown in a Drip Flow Biofilm Reactor and exposed to aromatic hydrocarbons phenol toluene. Ammonia oxidation rates, as measured by nitrite production biofilms, inhibited 50% when 56 µM or 100 toluene, while inhibition suspended cells occurred at 8 20 Biofilm‐grown dispersed into liquid medium immediately toluene experienced similar levels batch cells, indicating that mass transfer may be factor N....

Bacterially driven reactions such as ureolysis can induce calcium carbonate precipitation, a well-studied process called microbially induced precipitation (MICP). MICP is of interest in subsurface applications sealing leaks around wells. For effective field deployment, it important to study under radial flow conditions, which are relevant near-well environments. In this study, laboratory-scale reactor 23 cm diameter, with 1 mm glass bead monolayer serving porous medium, was used investigate...

Precipitation reactions influence transport properties in porous media and can be coupled to advective dispersive transport. For example, subsurface environments, mixing of groundwater injected solutions induce mineral supersaturation constituents drive precipitation reactions. Magnetic resonance imaging (MRI) microcomputed tomography (μ-CT) were employed as complementary techniques evaluate advection, dispersion, formation precipitate a 3D flow cell. Two parallel fluids flowed...

Abstract Technical communication skills are highly valued in the engineering[1] and practicing engineers spend a large portion of work time writing or speaking. However, feedback from industry indicates lack many engineering graduates[2]. Engineering curriculums therefore need to improve how taught. The movement towards more effective teaching has resulted opportunity for collaboration with experts. One issue is that technical writing, its products, often viewed as outside practice, e.g....