Collaborative Research: Development of a Novel Strategy for Using Waste Concrete to Mitigate Industrial Nitrogen Dioxide Emissions and to Inhibit Corrosion

Cement kilns are a significant contributor to anthropogenic nitrogen oxides emissions. This study seeks to demonstrate a promising and novel approach to the air pollution mitigation. A collaborative study will investigate an innovative approach to utilizing waste concrete material which, based on preliminary investigations, can economically and sustainably strip nitrogen dioxide from flue gas. The concrete waste containing sequestered pollutants can then be recycled as either set-accelerating or corrosion-inhibiting admixtures in new concrete. As a result, the approach can potentially turn waste materials into valuable products. The broader applications of the solution are not only in cement manufacturing, but also in incineration plants, boilers, process heaters, glass furnaces, and power plants. This project will be supported by an interdisciplinary team from Stony Brook and Clarkson Universities with highly complementary expertise in materials science, environmental chemistry and engineering, and civil engineering. The educational components of this project will focus on achieving the following objectives: (1) Expanding the undergraduate concentration in environmental engineering and chemistry; (2) Developing case studies that will allow students to grasp the fundamentals in environmental and civil engineering; (3) Increasing the number of underrepresented minority students who will be exposed to environmental chemistry, civil engineering and sustainability topics. The technical approach to achieve the above mentioned outcomes will include several experimental strategies. The nitrogen dioxide absorption capacity of the demolished concrete as a function of particle size, age, type of aggregate, composition, moisture content and ambient relative humidity and temperature will be determined using state of the art experimental methods, including advanced spectroscopic techniques, reactor studies, and microscopy. Subsequently, the newly acquired properties of nitrogen dioxide sequestered concrete, such as set-accelerating and/or corrosion-inhibiting properties, will be analyzed for application in new concrete. More specifically, comprehensive studies focused on hydration kinetics, microstructure development, volumetric porosity, chloride binding capacity, chloride diffusion resistance, and corrosion rate will be conducted using various analytical techniques such as isothermal conduction calorimetry, nano-tomography, and potentiodynamic polarization. The intellectual merits of these approaches are in distinct novelties of the applications and characterization strategies. Moreover, this project will create new knowledge specifying mechanisms of nitrogen dioxide interaction with concrete surface, environmental conditions needed to maximize the uptake, the chemistry of the end products, and the potential utilization of the end products as constituents in new concrete.