%0 Journal Article %1 steeb-2022k %A Weinhardt, Felix %A Deng, Jingxuan %A Hommel, Johannes %A Vahid Dastjerdi, Samaneh %A Gerlach, Robin %A Steeb, Holger %A Class, Holger %D 2022 %J Transport in Porous Media %K mib mib_ls2 mib_ls2_exc2075 mib_ls2_exc2075_PN1 mib_ls2_exc2075_PN1_PN1_4 mib_ls2_sfb1313 mib_ls2_sfb1313_B_B05 mib_ls2_sfb1313_b mib_ls2_steeb myown %N 2 %P 527--549 %R 10.1007/s11242-022-01782-8 %T Spatiotemporal Distribution of Precipitates and Mineral Phase Transition During Biomineralization Affect Porosity--Permeability Relationships %V 143 %X Enzymatically induced calcium carbonate precipitation is a promising geotechnique with the potential, for example, to seal leakage pathways in the subsurface or to stabilize soils. Precipitation of calcium carbonate in a porous medium reduces the porosity and, consequently, the permeability. With pseudo-2D microfluidic experiments, including pressure monitoring and, for visualization, optical microscopy and X-ray computed tomography, pore-space alterations were reliably related to corresponding hydraulic responses. The study comprises six experiments with two different pore structures, a simple, quasi-1D structure, and a 2D structure. Using a continuous injection strategy with either constant or step-wise reduced flow rates, we identified key mechanisms that significantly influence the relationship between porosity and permeability. In the quasi-1D structure, the location of precipitates is more relevant to the hydraulic response (pressure gradients) than the overall porosity change. In the quasi-2D structure, this is different, because flow can bypass locally clogged regions, thus leading to steadier porosity--permeability relationships. Moreover, in quasi-2D systems, during continuous injection, preferential flow paths can evolve and remain open. Classical porosity--permeability power-law relationships with constant exponents cannot adequately describe this phenomenon. We furthermore observed coexistence and transformation of different polymorphs of calcium carbonate, namely amorphous calcium carbonate, vaterite, and calcite and discuss their influence on the observed development of preferential flow paths. This has so far not been accounted for in the state-of-the-art approaches for porosity--permeability relationships during calcium carbonate precipitation in porous media.

@article{steeb-2022k, abstract = {Enzymatically induced calcium carbonate precipitation is a promising geotechnique with the potential, for example, to seal leakage pathways in the subsurface or to stabilize soils. Precipitation of calcium carbonate in a porous medium reduces the porosity and, consequently, the permeability. With pseudo-2D microfluidic experiments, including pressure monitoring and, for visualization, optical microscopy and X-ray computed tomography, pore-space alterations were reliably related to corresponding hydraulic responses. The study comprises six experiments with two different pore structures, a simple, quasi-1D structure, and a 2D structure. Using a continuous injection strategy with either constant or step-wise reduced flow rates, we identified key mechanisms that significantly influence the relationship between porosity and permeability. In the quasi-1D structure, the location of precipitates is more relevant to the hydraulic response (pressure gradients) than the overall porosity change. In the quasi-2D structure, this is different, because flow can bypass locally clogged regions, thus leading to steadier porosity--permeability relationships. Moreover, in quasi-2D systems, during continuous injection, preferential flow paths can evolve and remain open. Classical porosity--permeability power-law relationships with constant exponents cannot adequately describe this phenomenon. We furthermore observed coexistence and transformation of different polymorphs of calcium carbonate, namely amorphous calcium carbonate, vaterite, and calcite and discuss their influence on the observed development of preferential flow paths. This has so far not been accounted for in the state-of-the-art approaches for porosity--permeability relationships during calcium carbonate precipitation in porous media.}, added-at = {2022-08-04T11:12:52.000+0200}, author = {Weinhardt, Felix and Deng, Jingxuan and Hommel, Johannes and Vahid Dastjerdi, Samaneh and Gerlach, Robin and Steeb, Holger and Class, Holger}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2db17ea1e07cd3ac236837923d486ec3b/hsteeb}, doi = {10.1007/s11242-022-01782-8}, interhash = {a8fc39629d0645ef072272d32cb27e27}, intrahash = {db17ea1e07cd3ac236837923d486ec3b}, journal = {Transport in Porous Media}, keywords = {mib mib_ls2 mib_ls2_exc2075 mib_ls2_exc2075_PN1 mib_ls2_exc2075_PN1_PN1_4 mib_ls2_sfb1313 mib_ls2_sfb1313_B_B05 mib_ls2_sfb1313_b mib_ls2_steeb myown}, number = 2, pages = {527--549}, timestamp = {2023-02-08T20:11:10.000+0100}, title = {Spatiotemporal Distribution of Precipitates and Mineral Phase Transition During Biomineralization Affect Porosity--Permeability Relationships}, volume = 143, year = 2022 }