Perspectives for CCUS application in the construction value chain            

Abstract

The construction of buildings and infrastructure represents 15% of global GHG emissions. Carbon emissions need to be reduced to achieve climate goals, reach net-zero carbon emissions by 2050, and mitigate climate change. However, cement and steel production are hard-to-abate sectors: Their productions are difficult to decarbonize. Consequently, to counterbalance residual GHG emissions modeled mitigation strategies include net-zero and net-negative CO2 emissions. Here carbon capture, utilization, and storage (CCUS) emerges as an option. Through carbonation, Ca- or Mg-rich feedstocks (industrial wastes, natural minerals, or cement-based materials) react with CO2 to form carbonates and possibly silica gel. By doing so, the CO2 can be stored thermodynamically stable in added-value construction products such as aggregates, SCMs, concrete, or bricks. This paper aims to generate an overview of the current state of research, further research opportunities, and existing initiatives regarding CCUS in the construction sector (concrete, steel, brick). Thereby the methods and products from carbonation, the CO2 source, and storage, enforced carbonation factors in general and from selected companies as well as their technology readiness level (TRL) will be assessed.