Environment-friendly cement from bacteria EU-funded scientists have pioneered a bacterial cement production system that uses industrial waste streams to produce low-cost, sustainable cement. Climate Change and Environment © Shutterstock At present, the manufacturing of cement is highly unsustainable, being responsible for approximately 5 % of annual global carbon emissions. This figure is expected to grow rapidly; therefore, there is an urgent need for a method of cement production that is both economically viable and environmentally friendly. The aim of the ECO-CEMENT (New microbial carbonate precipitation technology for the production of high strength, economical and ecological cement) project was to develop environment-friendly cement. It employed biomimetic technology based on the natural creation of formations by bacterial precipitation of carbonate via urea hydrolysis. This has the benefits of valorising waste streams by using them as a raw material and diverting them from landfills, and avoiding major carbon emissions. Project partners began by identifying a number of waste streams that could be used as raw materials for bacteria to produce cement. These included cement kiln dust (a source of calcium), biological wastes (a source of urea) and dairy wastes as a source of nutrients for the bacteria. Researchers also investigated new ways of increasing Eco-Cement's strength and durability by adding microfibres or other ingredients. The team tested a number of bacteria that can perform the reaction needed for cement production. Sporosarcina pasteurii was identified as the most suitable due to its high reaction rate and overall environmental hardiness. Scientists also conducted a life-cycle assessment to measure how sustainable this process was in comparison to traditional cement production methods. It is estimated that Eco-Cement will lead to reductions in greenhouse gas emissions (11 %), construction waste (20 %) and overall production costs (21 %). It is also expected to lead to the creation of at least 2 000 new jobs across Europe. Keywords Environment-friendly, cement, bacteria, waste streams, carbon emissions, carbonate
