Low Temperature Curing Process Cuts Cement’s CO2 Emissions by 70%. The making of concrete is responsible for as much as 8 percent of annual global CO2 emissions. Now, according to a report in TreeHugger, LafargeHolcim, the world’s largest cement company, is going to be selling reduced CO2 cement for the precast industry in the US using technology from Solidia Technologie. The product is the result of a six-year collaboration between LaFargeHolcim and Solidia and uses a special binder — produced at lower temperatures — and patented curing process that uses CO2 rather than water. By adding and absorbing CO2, Solidia Concrete reaches strength in less than 24 hours unlike precast concrete made with Portland cement, which takes 28 days to reach strength. Solidia reduces the overall carbon footprint in precast concrete by 70%. In addition, the new product reduces the cement plant’s carbon emissions by up to 40%. This concrete can be made in a conventional cement kiln with the heat turned down, so it works within the existing systems of production. Treehugger, August 15, 2019, .https:// www-treehugger-com.cdn.ampproject.org/c/s/http://www.treehugger.com/sustainable-product-design/amp/ lafargeholcim-selling-co2-sucking-cement-precast-reduces-emissions-70-percent.html
New LED Materials Generate High Efficiency Light With Lower Manufacturing Costs. Dawei Di, a faculty member at Zhejiang University and a visiting researcher at the University of Cambridge, has co-invented new LED materials and devices that can generate light from electricity at maximum efficiency even when they need to reach high brightness. What’s more, they can be manufactured using cheaper, simpler, and less energy-intensive processes. Typical LED production lines require high-temperature processes or depositing light-emitting materials on a solid surface in a vacuum, and thus they use lots of energy. Di’s materials are cheaper because they can be made from widely available substances, and they don’t need to be deposited at high temperature or in a vacuum. Instead, they’re dissolved in a liquid and then coated onto a solid surface. A number of companies are already testing production lines with Di’s methods. MIT Technology Review, July-August 2019, https://www.technologyreview.com/lists/innovators-under-35/2019/inventor/dawei-di/
Most GHG emissions in transportation come from on-road vehicles, but construction is a large contributor as well. In particular, concrete manufacturing generates emissions both from energy needed to heat materials in cement kilns and from a chemical process known as “calcination.” Because concrete is so widely used these emissions are substantial, amounting to an estimated 5 percent of the world’s carbon dioxide emissions.
Cement kilns have improved their efficiency to some extent over time, but now the New York Times reports that a more substantial improvement may be on the way. A New Jersey-based startup, Solidia Technologies, has begun to commercialize a process that it claims reduces GHG emissions by up to 70 percent. The technology relies on lower-emission cement chemistry, and it sequesters carbon dioxide—from a companion industrial or power plant—during hardening.
The technology is currently being used for products such as walkway and driveway pavers, including some products sold by E.P. Henry in the United States. Poured and precast structural concrete using this technology is not yet available, but that time may come soon.
The Times cited Jan van Dokkum of the venture capital firm Kleiner Perkins: “Solidia may now be at the stage where solar power was a decade or more ago. A relatively few early adopters and government subsidies helped solar gain acceptance until the prices of panels came down, opening the way to today’s huge market. ‘Once we get this transition going,’ he said, ‘then suddenly this thing will boomerang through the industry.’”
Eric Sundquist is Director of SSTI.