Alternative Building Materials: Enabling Circularity

Currently building materials account for 49% of total carbon emissions over the life of a building. The industry is facing pressure to increase their sustainability efforts and embrace the circular economy.

Carbon negative aggregate for the construction industry can change the game for the built environment; delivering performance, sustainability and circularity.

Carbon Negative Aggregate

At Carbon8 Systems, we convert CO2 and industrial residues into carbon negative aggregate for use in the building industry. The aggregate, with various applications in construction, is high performing and reduces the carbon footprint of any construction project.

Not only does the manufactured aggregate replace the need to quarry natural aggregate, but also contains CO2 – that would otherwise have been emitted by heavy industry. The aggregate is made of upcycled industrial residues and CO2.

This is where the circular economy and carbon reduction meet: in the form of carbon negative aggregate.

The aggregate meets industry specifications and has valuable properties for various applications in construction including concrete blocks and ready-mix, green roofing, pipe bedding, and road filler. It is carbon negative, lightweight, water absorbent, insulating, has hygric properties, and is adaptable to client specifications.

With 2050 Net Zero ambitions at the forefront, alternative building materials like carbon negative aggregate will become a means to deliver performance and sustainability.

The Details.

Our carbon negative aggregate is manufactured through a process enabled by Accelerated Carbonation Technology (ACT). Carbonation is a natural process, and one of nature’s ways to sequester CO2. However, in nature, this reaction takes up to millions of years, whereas ACT controls and accelerates the process to 30 minutes.

As carbonation is an exothermic process, ACT enables the capture and permanent storage of CO2, without requiring energy to drive the reaction. The carbon captured is from heavy industry sites – facilitating the decarbonisation of the likes of cement, steel, EfW, and biomass plants. The CO2 is used to treat residues produced by these plants, diverting them from landfill.

The residues contain calcium and magnesium oxides, hydroxide and silicates, which react to CO2 in controlled and specific conditions. In its simplest form, the reaction is CaO + CO2 = CaCO3.

Hence, ACT controls the carbonation process to manufacture aggregate that is derived from captured CO2, residues from heavy industry, and thereby permanently storing the CO2 in a solid used in construction; carbon negative aggregate.

Green Roundabout