The aggregate manufacturing process uses a patented process – Accelerated Carbonation Technology (ACT) – where waste carbon dioxide gas is used as a resource to treat a wide range of thermal wastes.
Many thermal wastes react naturally with carbon dioxide and, if the reaction conditions are carefully controlled, this natural reaction can be accelerated, taking place in minutes rather than months or years and resulting in the formation of artificial limestone.
During the process, significant volumes of carbon dioxide are permanently captured as stable carbonates. The growth of the carbonates chemically stabilises and encapsulates contaminants reducing the pH of the system and locking up heavy metals.
In the Carbon8 manufacturing process, the carbonated material is blended with binders and fillers and then pelletised with further carbon dioxide to form a rounded aggregate (C8Agg) that has a number of applications in construction.
The resulting aggregate has captured more carbon dioxide than is used in the energy required in its manufacture resulting in the world’s first carbon negative aggregate.
The Carbon8 process has recently been recognised in a United Nations Environment Report and acknowledged as making “a demonstrable contribution to the developing European circular economy”