Bio-Mediate Cementation Technique
The utilization of aerobic and anaerobic bacterial processes provides a unique opportunity to harness natural biological processes for engineering purposes. In this study bacterial (microbial) mineral precipitation of calcium carbonate (calcite) was performed. The creation of calcium carbonate (calcite) cement occurs as a consequence of bacterial metabolic activity which raises the pH of the proximal environment. The local pH rise may be achieved by the production of ammonia and carbon dioxide resulting from the enzymatic hydrolysis of urea. Bacillus pasteurii, a common soil bacteria, uses urea as an energy source and produces ammonia which increases pH, in turn causing Ca2+ and CO32- to precipitate as CaCO3. Microbiologically-induced calcite precipitation occurs according to the reactions:
bob lynn on 06 Feb 12The Green Building Council of Australia (GBCA) has been ardently backing a complete retrofit of all 'brown' or sustainably unfit operational buildings in this country. Which is only logical, as these buildings, particularly in the commercial sector, join together to become the largest carbon emitters in Australia. Their move to transform these unfit buildings has received a huge boost recently, with the support of Australand for their Green Star - Performance rating tool. The rating tool will become the backbone of the GBCA's work moving forward, as it will most precisely "help building owners, operators and occupants to measure and monitor the environmental impact of their buildings and take practical action to improve their buildings' performance".
