DESC0025232

Statement of the problem: The Department of Energy is interested in technologies that support secure and cost-effective conversion of carbon dioxide. Mineralization of CO2 with alkaline materials, such as steel slag, can generate synthetic aggregates for various engineering applications, including substituting natural aggregates in concrete. The synthetic aggregates are anticipated to provide improved technical performance, contribute to emissions reduction, and result in lower costs. However, the production of synthetic aggregates requires additional capital investment and operational expenses (such as CO2 capture, storage, transport, and conversion), which adversely impact the economic viability and overall carbon footprint. General statement of how this problem is being addressed: In response to Topic C58-23a, this project will overcome the above-mentioned problem by two innovative strategies: 1) integrating synthetic aggregates production with biogas upgrading in anaerobic digestion process and 2) accelerating CO2 mineralization with cost-effective biocatalysis. What is to be done in Phase I: The overall objective of this project is to develop and evaluate cost-effective and low carbon strategy for synthetic aggregates production by integrating biogas upgrading and enzyme-boosted CO2 mineralization. There are four specific objectives in this Phase I project: (1) Preparation and characterization of biogas and steel slag (2) Production of synthetic aggregates with biogas and steel slag (3) Characterization of synthetic aggregates (4) TEA and LCA of the proposed system for further scale-up application Commercial Applications and Other Benefits: This project will reduce the greenhouse gas emissions for aggregate production by at least 20% with better or comparable economic viability and technical performance compared to natural aggregates production. The innovative approach will benefit multiple sectors (such as bioenergy and construction) and improve the ecological-economic feasibility of CO2 mineralization, contributing to the development of a sustainable society.