Dissolution experiments on dolerite quarry fines at low liquid-to-solid ratio: a source of calcium for MICP

Microbially induced calcite precipitation (MICP) is an emerging soil stabilisation technique consisting of the precipitation of the mineral calcite in the soil matrix. The components required for MICP are currently industry end products. In this study, the calcium release and reusability of calcium-rich silicate quarry fines, dolerite, were investigated in closed (batch reactor) and open (permeability test) systems at liquid-to-solid (L/S) mass ratios <= 1.5 for MICP applications. The large specific surface area and reactive surface area accelerated calcium release, achieving calcium concentrations between 10 and 23 mM for different settings. Dissolution in the batch reactor resulted in increased silt (<0.006 mm) and clay fractions. X-ray fluorescence analysis indicated no significant depletion of calcium in the dolerite after dissolution. The study showed that dolerite quarry fines dissolution in distilled water at low L/S ratios is a rich source of calcium for MICP applications.

Automated summary

This study investigated the calcium release and reusability of calcium-rich silicate quarry fines in closed and open systems for MICP applications. The results showed that the dissolution of dolerite quarry fines in distilled water at low L/S ratios is a viable option for providing a rich source of calcium in MICP applications.