Patent ID: 11130971

Abstract:
Disclosed herein is a process of forming an inorganic water barrier layer on top of a porous substrate by means of microbially induced calcium carbonate or calcite precipitation (MICP), the process comprising the steps of: providing a porous substrate having a surface; depositing a urease-active slurry onto the surface of the porous substrate to form a bioslurry layer; and subjecting the bioslurry layer to one or more treatments with an aqueous solution comprising urea and a water barrier source material to convert the bioslurry layer into an inorganic water barrier layer. The process further comprises a step of covering the bioslurry layer with a layer of a porous material that has a surface, where the one or more treatments with an aqueous solution comprising urea and a water barrier source material are initially applied to the surface of the porous material. The porous material acts as a reservoir for the aqueous solution to sustain the biocementation of bioslurry into the desired inorganic water barrier layer.