* This bacterium uses an enzyme to make its surroundings less acidic, which is a good environment for them to grow", said Ms Whiffin. The by-product of this reaction is calcium carbonate, or limestone
* Ms Whiffin believes her biotechnology work will have many applications, not only for restoring historical buildings, but also mine shafts and other industrial structures.
* In 2002, a Dutch company responded to Ms Whiffin's website and shipped sand samples from
* They were impressed by the capability of the bacteria to cement sand samples from Dutch dykes that protect the land from rising sea levels.
* a similar technique is being used to clean up strontium spills in the
The biggest block they have made as of 2009 was in a shipping container, just to prove that it can not only work in the laboratory
A major practical application for the biocementation technique will be in mining. It doesn’t need oxygenation. In theory we could solidify the sea bed before drilling for oil. We could also drill tunnels in the sand, we could make the sand harder so it doesn’t cave in.
There was a 2008 patent
The PHd thesis (Microbial CaCO3 precipitation for the production of biocement, Victoria Whiffin) was completed in 2004
After biocementation treatment, Koolschijn sand indicated a shear strength of 1.8 MPa and a stiffness of 250 MPa, which represents an 8-fold and 3-fold respective improvement in strength compared to unconsolidated sand. Significantly lower strength improvements were observed in sand mixed with peat.
There have been design competition wins in 2008 and 2010 for using this for barriers in the desert and for roads
The construction industry is slow to adopt new technology, so this will need to penetrate some unique niches where there is no established or adequate alternative. The mining and dike applications look to be first and perhaps some desert experiments in
UPDATE : The more than ten year history of this research and nearer term applications for stronger and cheaper dikes and for better mining.
The new “sandstone” road surface is produced by using sand and a specific type of bacteria. The idea belongs to designers Thomas Kosbau and Andrew Wetzler, who are the winners of the Korean green design competition the iida awards.
The team says that mixing common sand – one of the most abundant resources on the planet – with a solution containing the microorganism Bacillus Pasteurii could result in a cementing process that turns the mix into biologically-engineered hardened sandstone.
After the two are mixed, the solution is sprayed on yet another layer of sand. The microbes act again, solidifying the layer underneath, and resulting in a tough, road-worthy material that can sustain heavy traffic.
Additionally, given the low cost of manufacturing the material, it will be a lot cheaper to repair it as well. When cracks appear, all maintenance crews will have to do is spray some of the bacteria solution within, and leave the road to solidify again.