Biocement production from microbially induced calcium carbonate precipitation (MICP) is an environmentally friendly approach for construction works, but the use of calcium chloride (CaCl2) in the conventional MICP process is a cost-limiting factor. The aim of this work is to develop a method for producing soluble calcium ions through two waste sources, limestone powder derived from aggregate quarries and acetic acid derived from fast pyrolysis of lignocellulosic biomass, as a replacement for the reagent grade CaCl2 in the MICP process. The ratio of limestone powder to acetic acid solution was optimized for a desirable calcium concentration with an appropriate pH. Procedures for applying the urease-producing bacteria, urea, and calcium solutions were developed for a successful MICP process and were treated for sand column test. The engineering properties of the biocemented sand, including water permeability, unconfined compressive strength, and tensile strength, were evaluated as a function of the calcium ...
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