ENHANCEMENT OF MICROBIALLY INDUCED CARBONATE PRECIPITATION USING ORGANIC BIOPOLYMER
Keywords:
Bio-polymer, Crystals, Morphology, Ureolytic bacteriaAbstract
Microbially induced carbonate precipitation (MICP) by using ureolytic bacteria is a novel and
environmentally friendly way to treat the un-cemented sand. It was implemented successfully in number of
geotechnical applications. Use of organic additives to improve the MICP process is a novel and interesting
approach. In this research, effect of the cationic biopolymer poly-l-lysine on the MICP process was investigated
by using ureolytic bacteria Pararhodobacter sp. Urea hydrolysis by the bacteria in the presence of CaCl2 was
conducted with the addition of the polymer under different conditions. Morphology of the precipitate of CaCO3
after oven dried was analyzed by using the scanning electron microscope. Bell-shaped curve was obtained for the
variation between the amount of the precipitate with the increase of the amount of the poly-l-lysine. Poly-L-
lysine gives higher amount of precipitate than conventional MICP process and morphology of the crystals
changed drastically from well-developed rhombohedral crystals to ellipsoidal shaped aggregates.