USA – Changing cement, changing emissions for the better

The Portland Cement Association announced the latest effort by the industry to significantly reduce the emissions burden on the environment. Tom Chizmadia, PCA board member and chairman of its Environment and Energy Committee, outlined the change in Portland cement production by including up to five per cent ground limestone in ASTM C 150 Portland cement. Chizmadia stressed the importance of this move: “Such reductions could add significantly to the environmental gains already achieved by the cement industry, and are clearly in line with the nation’s global climate policy goal of reducing greenhouse gas emission intensities.”

The environmental benefits include :
- A reduced use of raw materials
- Lower energy consumption
- Reduced greenhouse emissions.
Assuming 2.5 per cent limestone is used on average, the annual benefits include:
- Raw material use would decrease by 1.6Mt
- Energy use would fall by over 11.8tn BTUs
- Carbon dioxide emissions would be reduced by over 2.5Mt.
These benefits would allow a voluntary positive impact on greenhouse gas emissions.

The proposed change would bring US standards in line with European and Canadian standards, which have incorporated the use of limestone for decades.