US company makes greener concrete with microbes

Innovative technology has been developed that uses microbes to reduce carbon emissions during the manufacture of concrete.

After water, concrete is the most widely used material in the world, with most commercial buildings and homes having concrete flooring, and the substance being used to make roads and bridges. Concrete is a mixture of crushed rocks and water with cement binding them together. Cement is usually made by burning limestone in coal-fired furnaces.

A North Carolina company, Biomason, has developed a new way of making concrete that requires no cement, so keeps carbon emissions down. Instead, it uses living microbes mixed with a powder containing carbon and nitrogen. The microbes bind the crushed rocks and water together without the need for limestone. This significantly reduces carbon emissions in the concrete manufacturing process. Another benefit of the concrete manufactured by Biomason is that it is less prone to cracking.

Biomason currently only makes concrete blocks using living microbes. It is developing ways to make ready-mix concrete which can be poured to make concrete flooring and other large concrete structures. Around 85% of applications of concrete in the construction industry use ready-mix concrete.

Building developers are looking at ways to make construction more environmentally friendly. For example, the clothing group H&M is committed to using sustainable concrete flooring in every new store. If greener concrete can be mass produced, it will make a significant difference in construction projects by reducing carbon emissions levels without sacrificing on the strengths of concrete.