Transport and Fate of Ureolytic Sporosarcina pasteurii in Saturated Sand Columns: Experiments and Modelling

Abstarct Despite a broad application of ureolytic bacteria in many bioremediation and biocementation processes, very limited studies have reported their transport retention behaviors under various physical–chemical–biological conditions. In this study, we report Sporosarcina pasteurii saturated sand, based on series column breakthrough experiments different conditions including ionic strengths (ISs: 0.5 mM–1 M), flow velocity (50, 100, 200 cm/h), optical density (OD 600 = 1.0, 0.48), length (280 mm, 150 mm), changes IS (0.5 M CaCl 2 or deionised water). We use two-site kinetic model, representing (1) attachment grain surfaces, (2) straining at crevices constrictions, to quantify predict the bacterial straining. Model parameters were calibrated by tracer (NaCl) curves (BTCs) BTCs IS/velocity The model was then applied successfully lower initial 0.48) for shorter lengths (150 mm). demonstrated that higher strength (from 1000 mM) dramatically enhanced efficiency S. through an enhancement 9.4 69.6%) 8.1 34.2%), whilst survival urease activity unaffected high (500 mM NaCl) within 5 h. Increasing 50 cm/h) caused decrease 39.5 22.4%) 40.5 19.3%) as result increased hydrodynamic shear forces, which tends reduce secondary minimum extent stagnation regions Lower OD 1.0 31.8 40.9%) 22.9 42.2%) reducing site-blockage effect. addition, with stronger column, water release. These findings provide useful information better understanding fate soil, can be used optimise bioaugmentation strategy cementation soil improvement. Article Highlights Transport sands is highly affected strength, velocity, density, even size Straining 8.1% 34.2%) if increasing 500 without affecting Bacteria coagulation among 2–3 cells occurs ISs forming large flocculation