Silicate production and availability for mineral carbonation

P. Renforth*, C.-L. Washbourne, J. Taylder, and D. A. C. Manning

Abstract

Atmospheric carbon dioxide sequestered as carbonates through

the accelerated weathering of silicate minerals is proposed as a climate change

mitigation technology with the potential to capture billions of tonnes of carbon

per year. Although these materials can be mined expressly for carbonation, they

are also produced by human activities (cement, iron and steel making, coal

combustion, etc.). Despite their potential, there is poor global accounting of

silicates produced in this way. This paper presents production estimates (by

proxy) of various silicate materials including aggregate and mine waste, cement

kiln dust, construction and demolition waste, iron and steel slag, and fuel ash.

Approximately 7-17 billion tonnes are produced globally each year with an

approximate annual sequestration potential of 190-332 million tonnes C.

These estimates provide justification for additional research to accurately

quantify the contemporary production of silicate minerals and to determine

the location and carbon capture potential of historic material accumulations.

r2011 American Chemical Society 2035