Cement is the gray glue that holds our modern cities and infrastructure together. We use about 4.1 billion tons of it a year, and every ton has a carbon debt of about a ton of carbon dioxide. That’s about 10% of our global emissions, so it’s a big problem. From India to the UK to the USA, calcined clays are one of the big levers governments and industry are straining to pull.
It’s a fairly recent cement variant, having emerged in the early 2010s from research done in Europe and India, for the most part. Pilot projects have sprung up, and India is leading in the space, with a pilot plant, several demonstration buildings, and lots of work done across the country to create the conditions for change to shift from Portland cement.
Adding another 10% of capital costs has to be paid for with higher prices for cement, but that’s not a big kicker, perhaps $2.25 per ton of cement. That’s 1.5% to 4% of the cost of cement in Europe, India, and China per my quick calculations. Not insurmountable. There’s another factor to consider. The kaolin deposits aren’t just more expensive to mine, they aren’t right beside cement plants, which are evenly distributed. I did some assessment on the concentrations of kaolin deposits in India vs population and economic activity. The states of Gujarat, Kerala, and Rajasthan have big clay deposits, and Gujarat is a center of heavy industry already.
Cement is such an incredibly important industrial commodity, necessary for keeping pretty much every that sticks up above ground staying upright and everything below ground from collapsing in cave-ins, that it’s a very heavily regulated substance for quality. That regulation isn’t just national and international standards, although that’s a bunch of the work that’s being done around it.
Even after that, then everyone who works with cement in the building industry has to be familiarized with LC3 and its specific characteristics. Every engineer who does finite element analysis has to be read in. All of the inspectors who sign off on plans and construction have to be educated. All of the construction companies have to be educated. All of the customers have to be educated on why their buildings cost more.