Cement and concrete are indispensable in our modern society; every structure we see all around us is made of it, from roads, buildings, bridges, houses, etc. The problem is that cement production is highly carbon-intensive as it uses coals to fire up the kilns contributing to 7 per cent of the total global emissions.
Reducing emissions in cement production is challenging, but solutions are available such as improving energy-efficiency, applying carbon capture technology (CCS), fuel substitution with waste like used tyres, certain plastics, biomass, etc., or reducing or substituting clinker.
A cement plant in New Zealand has replaced coal with used car tyres to fuel its kiln. The total government subsidy of around $41 million has helped upgrade the plant to use waste in its cement production.
The Stuff article reports that this new initiative will prevent 3 million used tyres from going to the landfills each year.
According to the NZ Environment Minister David Parker, the project is “a win-win for the environment”. He added that the plant would reduce waste and carbon emissions by about 13,000 tonnes a year.
Ross Taylor, CEO of Fletcher Building, a company that owns the plant, says that “When you burn tyres at such a high temperature there’s no smoke, there’s no smells because it consumes everything and they release less CO2, which is where the saving comes from.”
The cement plant also aims to reduce coal use by 15%, reduce iron sand use by 5000 tonnes and carbon emissions.
Cembureua, The European Cement Association is investing in solutions and innovations to drive down emissions from the cement industry. Their initiative involves four main “levers” – thermal efficiency, fuel substitution, clinker substitution, carbon capture.
Their website presents some breakthrough technologies that they have been testing, like new types of clinker that require lower temperatures to produce and partially electrifying cement production, strategies aimed to lower carbon emissions.
The New Zealand cement plant and other cement and concrete industries worldwide have demonstrated that successful application of climate mitigation strategies and climate actions is possible when all actors in society, from the government to private corporations and manufacturing industries, work towards the same goal.