Biogeochemical simulation of microbially induced calcite precipitation with Pararhodobacter sp. strain SO1

Abstract

Biogrouting is a ground improvement technique, which utilizes microorganisms. The numerical simulation of biogrouting is important to ensure efficient operation and to assess the applicability to the target ground. In this study, we compared syringe-scale biogrouting with biogeochemical simulation. Parameters suitable for practical applications were included. The rate constant and half-saturation constant of the reaction rate law in ureolytic bacteria Pararhodobacter sp. strain SO1, obtained from the simulation based on the urease activity test, were 1 × 10-8 mol/mg/s and 0.635 M, respectively. To achieve the same mineral precipitation in measurement and simulation, a setting in which only the calcite precipitated was used. In the sequential simulation of the solidification test, a variation in discharged Ca 2+ concentration was reproduced by introducing an "adjustment index," which considers the microbial biomass contributing to the reaction. Moreover, for the re-injection test, in which microbes were injected again to further improve the biogrout strength, the settings were validated by the sequential simulation followed by predictive simulation on different injection dates. The results indicate that by conducting a biogeochemical simulation of calcite precipitation for biogrouting using ureolytic bacteria, the strength of biogrout can be predicted and managed.

Incorporation of Optical Density into the Blending Design for a Biocement Solution

“…However, the results and evaluation in engineering may have similarities. The microbial precipitation of carbonate using ureolytic activity has been increasingly studied worldwide and the objectives of studies have been expanding [ 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 , 17 , 18 ]. These are based on microbially induced carbonate precipitation and are often called MICP techniques.…”

Calcium Carbonate Growth with the Ring Structure of Stalactite-Type Minerals in a Tuff Breccia

“…For example, studies have focused on developing ecological techniques for repairing limestone using biomineralization [7][8][9]. Calcium carbonate can be used as a repairing material by biomediated precipitation as a by-product of microbial metabolic reactions such as photosynthesis [3,[9][10][11][12] and urea decomposition [3,9,[13][14][15][16][17][18][19][20][21][22][23][24]. In these biomediated environments, the cell wall and extracellular polymeric substances of the microorganism act as centers for carbonate precipitation [1,3,25].…”