Mineral changes in cement-sandstone matrices induced by biocementation

Abstract

Prevention of wellbore CO 2 leakage is a critical component of any successful carbon capture, utilization, and storage program. Sporosarcina pasteurii is a bacterium that has demonstrated the potential ability to seal a compromised wellbore through the enzymatic precipitation of CaCO 3. Here we investigate the growth of S. pasteurii in a synthetic brine that mimics the Illinois Basin and on Mt. Simon sandstone encased in Class H Portland cement under high pressure and supercritical CO 2 (P CO2) conditions. The bacterium grew optimum at 30 o C compared to 40 o C under ambient and high pressure (10 MPa) conditions; and growth was comparable in experiments at high P CO2. Sporosarcina pasteurii actively induced the biomineralization of CaCO 3 polymorphs and MgCa(CO 3) 2 in both ambient and high pressure conditions as observed in electron microscopy. In contrast, abiotic (non-biological) samples exposed to CO 2 resulted in the formation of surficial vaterite and calcite. The ability of S. pasteurii to grow under subsurface conditions may be a promising mechanism to enhance wellbore integrity.

Real-Time Metabolic Interactions between Two Bacterial Species Using a Carbon-Based pH Microsensor as a Scanning Electrochemical Microscopy Probe

“…In recent decades, researchers have reported 14–16 the use of scanning electrochemical microscopy (SECM) in the study of various biological systems, including microbial biofilms. 17–20 SECM was used in several studies 21,22 to map the local pH on a wide variety of substrates.…”

Applications of Microbial Processes in Geotechnical Engineering

“…growth of indigenous ureolytic bacteria) may be problematic in subsurface conditions with limited oxygen supply. Pressure: S. pasteurii has been shown to continue to grow and hydrolyse urea at pressures from 7.5 to 10 MPa and at temperatures between 30 and 40ºC Verba et al, 2016). Cunningham et al (2014) (2009) found that between 5°C and 70°C the rate of ureolysis doubled approximately every 8°C.…”

Numerical analysis of a parabolic variational inequality system modeling biofilm growth at the porescale

“…In this paper we focus on the applications involving "selective plugging" by biofilm in porous media such as, e.g., in microbial enhanced oil recovery (MEOR) and in carbon sequestration. In these applications the microbes coat the grains of the porous medium and plug the high-permeability zones thereby enhancing overall recovery [16] or preventing leakage by promoting mineralization [10,25,7].…”

“…The EPS matrix protects the cells, which tend to aggregate, and it is not penetrated by larger molecules, e.g., of imaging contrast. The interface between the biofilm domain denoted by Ω * (t) = {x ∈ Ω : B(x, t) = B * }, and the surrounding fluid domain Ω − (t) = {x : B(x, t) < B * } is a free boundary Γ(t) = ∂Ω * (t) ∩ ∂Ω − (t) visible to human eye and easily recognized by xray µ-CT tomography or other microscopy equipment; see [18,25,7]. The growth of Ω * (t) proceeds through interface only; this explains the tapering of exponential growth reported, e.g., in [7].…”

“…Literature remarks. Numerical simulation of biofilm growth is of interest because the physical experiments with biofilm and its imaging are quite difficult [18,10,25,7]. Various models for biomass growth and biofilm growth address the growth at the porescale and the permeability of the porous domains plugged up by biofilm; however, their focus is selective.…”