Development of NetZero carbonated recycled aggregates and recycled aggregate concrete

Aiming at sustainable development goals, environmental agendas related to global warming deserve to be highlighted due to the urgency of the theme.

The annual emission of 3.6 billion tons of carbon dioxide (CO2) into the atmosphere aggravates the greenhouse effect, raising the average temperature of the planet and negatively impacting ecosystems.

In this regard, researchers have been studying new ways to reduce the impact generated by excess CO2 in the atmosphere, leading to the development of new technologies that seek to sequester CO2, called carbon capture, use and storage (CCUS). Cementitious materials have the ability to perform carbon capture by the carbonation process.

In addition, the consolidation of carbon credit markets (emission trading system - ETS) adds value to the subject by trading CO2 emission rights, enhancing this practice as a form of financial gain.

In addition, another important agenda for sustainable development is associated with the reuse of construction and demolition waste (CDW).

Waste generated from cementitious materials, such as concrete, mortar and cement paste, can be used to make CCUS, gaining greater market value and potential to be recycled.

Therefore, the objective of this research is to contribute to the theme in order to consolidate CDW as materials that can be applied to capture carbon, increasing recycling and market value.

The proposal aims to fill gaps found in the literature as a method for separating the cementitious content from the other components of CDW, a consolidated model for calculating captured CO2, a methodology to obtain the captured CO2 content with variables related to carbonation and CDW, and to explore the absorption capacity of CO2 in ETS, something not covered in the literature.

To this end, the physical characterization of CDW materials will be carried out, with varied granulometry and composition, followed by carbonation in a climatic chamber with different levels of pressure, temperature, humidity and concentration of CO2 in the atmosphere.

After carbonation, the differential thermogravimetric analysis (TGA/DTG) will be performed to verify the CO2 content captured by the different existing methodologies and the formulation of a new one considering the variables previously expressed, aiming to contribute to this theme.

In the end, the potential application of the carbon content captured in ETS will be calculated, aiming to support this proposal.