/ 24 June 2011

Building on a small footprint for cement

Building On A Small Footprint For Cement

Years before “carbon emissions”, “energy efficiency” and “carbon footprint” became buzzwords in industry, AfriSam South Africa committed itself to reducing its burden on the environment.

Today the construction materials group is an industry leader in emissions reduction and energy management. It also created the world’s first CO2 measurement rating for its products.

The Greening the Future judges singled out AfriSam for setting new benchmarks in theconstruction industry. “Its CO2 rating is a market-changing approach,” they say. Cement production is a key source of carbon emissions worldwide.

“We realised there’s a delicate balance that needs to be maintained between our emissions and the imperative to protect the planet,” says chief executive Stephan Olivier. “Our focus on carbon reduction and energy-reduction initiatives has put us at the forefront in balancing economic progress and due care for the environment.”

The company began monitoring its greenhouse gas emissions in 1990 and published an environmental policy four years later. In 2000 it implemented a fully fledged CO2 reduction programme and set ambitious targets to reduce emissions associated with its products.

The company took its first major step towards CO2 reduction by launching Project Green Cement in 2000. “By using carefully selected by-products from the steel, energy andother industries to extend cement, we are able to reduce the amount of clinker in it without compromising on quality,” says Claudene Moorgas, the company’s environmental manager.

Raw clinker — the main ingredient of cement — is highly energy-intensive and has a significant CO2 footprint. Blending it with other materials means a reduced carbon footprint and a significant saving on energy consumption.

From 2002 to 2005 AfriSam installed sophisticated emission-measuring equipment in all its kiln stacks. It was the first cement producer in Southern Africa to do so. This, coupled with the installation of the first bag-house filters for the cement kiln stacks, enabled its Dudfield factory to have the cleanest kiln emissions in Southern Africa.

“Between 1990 and 2010, we reduced our CO2 emissions per ton of cement by more than 30%,” says Moorgas. In 2009 the company introduced a world-first CO2 rating system on all its cement bags. The carbon footprint of each AfriSam product relative to the world average is printed on every bag.

“As customers become increasingly aware of climate change and other threats, they look to make environmentally responsible purchasing decisions. We want them to be assured that we are making environmentally responsible production decisions, too,” Moorgas says.

AfriSam launched its Eco Building Cement in 2010, which uses slag instead of clinker to extend cement. This product has a carbon footprint of 414g per kg — half the world average of 890g per kg for cement, as calculated by Cembureau, the European Cement Association. Its latest product, Eco Readymix concrete, has an even lower carbon footprint.

“We’ve achieved this reduction without forgoing on quality,” says Moorgas. “Our Eco Building products meet SABS standards for their strength class and are competitively priced. We don’t charge a premium on these products because they are greener than others.”

Advanced fuel- and energy-efficient technologies play a major role in reducing emissions. “We were the first South African company to install an energy efficient vertical roller mill for raw-material preparation and grinding of cement.

“When we began Project Green Cement, we installed state-of-the-art blenders, which allowed us to blend cement with extenders. By using these extenders we consume 60% less electrical and thermal energy in the cement production process,” says Moorgas.

The company has also invested in major energy-efficient upgrades of equipment at its production plants and employed a team of process engineers to get maximum energy efficiency out of each plant component. These measures, alongside behavioural, educational and staff advocacy initiatives, have yielded significant energy savings.

Using 2000 as its base year, AfriSam has reduced its electrical energy consumption by 25% and its thermal energy consumption by 40%. “We pride ourselves on leading the pack when it comes to carbon emission reduction and energy management in our industry. We want to maintain this through forward-thinking and constantly looking at all avenues to reduce our impact on the environment,” says Moorgas.