Knife River eyes carbon accounting, synthetic aggregate with Blue Planet stake

Sources: MDU Resource Group, Bismarck, N.D.; CP staff Knife River Corp. has invested in California-based Blue Planet Systems Corp., whose process for mineralizing carbon dioxide into synthetic limestone is approaching commercial scale. The companies will work to develop construction-grade rock and ultimately specification concrete bearing a net-zero or net-negative carbon footprint. 

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Rebar top gun Nucor wires renewable energy into steelmaking loop

Sources: Nucor Corp., Charlotte, N.C.; CP staff Leading concrete reinforcing steel producer and fabricator Nucor has signed a 15-year Virtual Power Purchase Agreement with EDF Renewables North America for 250 megawatts of new solar array-derived energy in Texas. A first for Nucor, the agreement positions EDF Renewables to add more clean energy to the South Central power grid and becomes…

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LafargeHolcim adopts new label for low CO2 and recycled content materials

Sources: LafargeHolcim Ltd., Zurich; CP staff Cement and concrete from LafargeHolcim will soon bear a logo shaped like a mobile device icon indicating two principal qualities realized in processing, mix design and batching: A carbon dioxide emissions footprint 30 percent or lower compared to local industry standard and a minimum 20 percent recycled material content. The producer revealed the EcoLabel…

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Cemex begins global rollout of branded, net-zero CO2 concrete

Sources: Cemex S.A.B. de C.V., Monterrey, Mexico; CP staff The first-ever net-zero carbon dioxide concrete from Cemex will soon be available in the producer’s major markets worldwide after a successful launch in Europe. A series ranging from low carbon to net-zero CO2 mixes, Vertua is based on a geopolymer binder solution from the Cemex Research and Development Center in Switzerland. Compared to…

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PCA programs portland-limestone cement promotion

carbon calculator

Sources: Portland Cement Association, Washington, D.C.; CP staff PCA’s just-launched microsite, www.greenercement.com, supports the use of portland-limestone cement (PLC), which performs in concrete at levels comparable to Type I portland cement, but exhibits a greenhouse gas emissions profile up to 10 percent below clinker-only powder. The site accesses a calculator where design and construction professionals can input building size or…

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Ready mixed producers cut carbon footprint by double digits

Data behind a new National Ready Mixed Concrete Association life cycle assessment report for cast-in-place concrete shows how ready mixed producers, through more efficient use of portland cement, have cut the respective carbon footprints of 4,000- and 8,000-psi orders by 13 percent and 20 percent since 2014. Armed with results from a survey of 155 member producers operating 1,954 ready mixed plants, the association analyzed data on material throughput and other metrics reflecting net energy consumption in slabs or structures.

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Ready mixed producers quantify double-digit carbon footprint cut

Sources: National Ready Mixed Concrete Association, Alexandria, Va.; CP staff

Data behind a new NRMCA life cycle assessment report for finished concrete shows how ready mixed producers, through more efficient use of portland cement, have cut the respective carbon footprints of 4,000 psi and 8,000 psi orders by 13 percent and 20 percent since 2014. The association surveyed 155 member producers representing 1,954 ready mixed plants, analyzing data on material throughput and other metrics reflecting net energy consumption in slabs or structures.

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Paying attention to the carbon footprint behind the wood curtain

“Determining the Carbon Footprint of Wood” (PCA R&D 3287) is a valuable work based on Portland Cement Association-sponsored research. The timely report tracks trees and forests’ carbon dioxide-sequestering capacity, one of the value propositions wood building product interests channel to green-building practitioners; paints rationale for the wood industry to document carbon accounting methods transparently, especially when product is not sourced from a sustainably managed forest; and, helps cast-in-place concrete, precast and masonry construction practitioners respond to competitors’ claims of environmental mettle.

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CalStar begins production at two-line, Mississippi masonry plant

CAPTION:The cast stone products are made with CalStar’s proprietary process that incorporates up to 37 percent recycled content and eliminates the need for portland cement; calcium silicate materials, which require energy-intensive autoclaving; or for kiln-firing, typical of traditional clay brick. When measured against portland cement and clay alternatives, each CalStar product requires up to 81 percent less energy to make while emitting up to 84 percent less carbon dioxide.

CalStar Products has begun delivering building and landscape units from a 100,000-sq.-ft., Columbus, Miss., operation—an ambitious satellite to a Racine, Wis., flagship plant opened in 2010. With dry- and wet-cast lines for brick, trim and paver products using proprietary binders and high fly ash content, the facility sits on 23 acres in the Golden Triangle Industrial Park.

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