Microbial Curing of Cement for Energy Applications
Ordinary Portland Cement (OPC), the industry standard to manufacture concrete, requires a large quantity of fuel to produce, making it energy intensive. Further, ~7% of worldwide human-caused CO2 emissions aredue to the fuel combustion and natural evolution of CO2 from OPC’s feedstocks. In 2007, Rutgers University invented a new carbonate cement concrete process that uses up to 30% less energy and emits 40% less CO2 than OPC to create a sustainable cement (C3) suitable for pre-cast concrete applications. However, the current method used to harden this concrete, external introduction of CO2, limits the product thickness, which restricts use in some pre-cast and cast-in-place applications.
Project Innovation + Advantages:
Rutgers University, Lawrence Livermore National Laboratory, and the University of Arizona will develop a new hardening method for C3 to address thickness. C3 synthesis currently relies on externally-introduced carbon dioxide for solidification. This program will use microbes mixed into the C3 prior to curing to produce carbon dioxide internally for solidification. This microbial-cured C3 is expected to last longer than OPC at the same thickness, which will reduce the need for concrete repair and replacement. This in turn reduces energy consumption, carbon dioxide emissions, and costs associated with concrete-based projects.
Rutgers’ more energy and emissions efficient microbial-cured C3 manufacturing process will create new materials and processing methods, many of which will be useful for energy applications such as infrastructure, building components, and mending leaking fissures in geothermal and oil and gas wells.
The ability to cast a 50 Megapascal (7,252 pounds per square inch) shape in fewer than four hours means building infrastructure can be completed rapidly. The military will be able to quickly build and repair forward operating bases and aircraft runways.
A low carbon footprint concrete avoids and consumes CO2 emissions by as much as ~3 billion tons per year. Microbial C3’s durability and high strength will also reduce energy and water usage and CO2 emissions, because building and infrastructure projects to replace crumbling structures will be done less often.
Microbial C3’s fast drying time and avoidance of the curing-induced shrinkage cracks that plague traditional concretes, would allow larger castings and enable infrastructure and building-scale concrete projects to be completed faster. This technology saves significant money by reducing labor costs and improving the durability of concrete, limiting the need for repair and replacement.