Ahmad Fahmi

In this research, the potential of using the microbial-induced carbonate precipitation method was considered for the stabilization of sand using corn steep liquor, the byproduct of Glucosan Factory (Qazvin, Iran) and an inexpensive culture media for preparation of bacterial suspensions. Sporosarsina pasteurii, a urease-producing bacterium, was used for preparing bacterial suspension. The aim was also to compare the use of the industrial dehydrate calcium chloride and tetra hydrate calcium nitrate as calcium reagents in cementation solutions to treat loose silica sand samples using the microbial-induced calcite precipitation method. The results showed that corn steep liquor with 10% dilution rate could be used in culture media instead of yeast extract to prepare bacterial suspensions with appropriate specific urease activity. The unconfined compression strengths of the treated samples with two types of calcium reagents with limited concentrations (0.75M) were not significantly different. However, in the surface stabilization of sand dunes, it seems that the use of calcium nitrate is preferred to calcium chloride from an environmental perspective. It is concluded that, in industrial field-scale projects, both industrial dehydrate calcium chloride and tetra hydrate calcium nitrate reagents could be used as inexpensive calcium sources for microbial sand stabilization, and corn steep liquor could be used as an inexpensive alternative for yeast extract.