Concrete Construction's Focus On Sustainability

The efforts continue as the cement and concrete industry drives forward on the Roadmap to Net-Zero.

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Globally, the cement and concrete industry is responsible for 8% of worldwide carbon dioxide emissions. If it was a country, this would make it the third-largest producer on the planet. This represents emissions up and down the full supply chain—from the limestone mine all the way to placement. 

Reducing the cement and concrete industry's effect on global warming will take a massive amount of work. Levers are being pulled and more to come. 

The Portland Cement Association (PCA), the premier policy, research, education, and market intelligence organization serving America's cement manufacturers, originally launched its Roadmap two years ago committing the goal of achieving carbon neutrality across the cement and concrete value chain by 2050. Recently, the PCA has received bipartisan support for the Roadmap. 

Admittedly, many of the levers on the Roadmap to carbon neutrality are at the cement plant but that doesn't mean there aren't any at the jobsiteor tools available for contractors to watch the industry's efforts. 

Thus far, the cement industry has been vigilant but there's work that can be done at the site as well. For one, continue to place quality concrete. Concrete has a natural quality that allows it to act as a carbon sink and absorb CO2 from the air in the carbonation process. To put it simply, the process is similar to a tree and offsetting a percentage of emissions naturally (too bad we don't get oxygen from concrete, someone get to work on that).

Another example for the jobsite is opting for alternative-powered equipment and tools when possible. The use of battery-powered equipment has become more widely accepted than ever before. Electric machines from Caterpillar, SANY, and many others are being work-tested to make sure they are as reliable as contractors need them to be. Concrete equipment like Ligchine's SCREEDSAVER MAX PLUS E laser screeds, roller screeds from Curb Roller, concrete pencil and backpack vibrators, and Toro's s-2500 Electric Buggy are all great examples of innovative companies "taking the charge" by providing a green option for contractors. 

Concrete Contractor caught up with Mike Ireland, president and CEO of PCA during CONEXPO/CON-AGG 2023. The road we have ahead is long, but he's optimistic. Currently, carbon reduction projects have funding, but he anticipates more on the way. However, it's not a short trip. He says that a lot of these projects can take 5 to 6 years to be up and running. Recognizing that these projects and moves are expansive and will consume a lot of energy, the PCA is continuously researching what can be downstream to ensure sustainable efforts are made each step of the way. 

Listen to More Conversations on Sustainability by ForConstructionPros.com

"Society Needs Concrete; Concrete Needs Society" is a multi-part series on the PCA Roadmap to Carbon Neutrality. Featuring Rick Bohan, vice president of sustainability. 

Trends and Future Outlook of Electrification in the Off-highway Equipment Industry - David Venable, director - Off-highway Sub-segment Leader, Cummins Inc., discusses electrification in the off-road industry including current trends and a look into the future.

Find more podcasts from ForConstructionPros.com.

Cement & Concrete Wins

Even though the cement and concrete industry has had the Roadmap for a couple of short years, there have been some significant advancements already.

  • 46 state Departments of Transportation have approved the use of PLCs for their road and highway infrastructure - the remaining four are in progress.
  • Expansion of supplementary cementitious materials (SCM) and PLC products.

According to Holcim, their ECOPact low-carbon concrete product provides 30-90% lower CO2 than standard concrete. ECOPact won the Contractor's Choice "Next Level" award during CONEXPO/CON-AGG 2023. Contractors will be able to find ECOPact wherever the materials are available. Prior to the show, they expanded the availability by launching it in the Twin Cities, Minnesota, and Fargo markets. ECOPact was first launched throughout the Boston and Washington DC metropolitan areas in 2020.  Up to 80% less carbon is achieved primarily through the use of lower CO2-intensive materials. Where conditions allow, ECOPact products can even integrate construction and demolition waste, thus closing the material cycle completely.

Solidia Technologies expanded the production capacity of its proprietary SCM at its San Antonio, Texas headquarters. Solidia’s high-performing engineered SCM product improves the durability, workability, and overall properties of concrete while mineralizing captured CO2 to reduce greenhouse gas emissions by 30-40%. With significantly more production capacity and proximity to key customers, suppliers, and partners, the expansion continues the company’s move from research and development into commercialization.

According to Pradeep Ghosh, the company's senior director of strategy and business development, the production expansion should increase Solidia's capacity to about 1,000 tonnes. The expanded capability is also a first step toward addressing the supply chain challenges ready-mix producers are experiencing with cement and existing SCMs such as fly ash.

  • 60% of European cement plans are using alternative fuelsaccording to Ireland (PCA), one South Carolina cement plant has become almost waste-free.
  • Cement plants are receiving the EnergyStar certificationsin fact, the PCA itself received this recognition; the first association to be awarded the certification.
  • Captured energies at the plant like hydrogen and carbon can be utilized elsewhere either as an alternative fuel source or reintroduced to concrete as a strength enhancera tactic being utilized often at modern precast plants to increase its concrete strength.

For example, Carbonaide, a spin-out company from VTT Technical Research Centre (Finland), has announced that it raised €1.8 million in seed funding to integrate CO2 curing technology into an automated production line of its precast concrete factory in Hollola, Finland. The integration should mineralize up to 5 tons of CO2 per day and increase production by 100-fold of its carbon-negative concrete products. The pilot program conducted in autumn 2022 demonstrated that they were able to lower their products' carbon footprint to -60 kg per cubic meter by replacing portland cement with slag. 

“Our goal at Carbonaide is to create a more sustainable future with cutting-edge tech that doesn’t just reduce the carbon emissions of construction materials like concrete, but that traps more CO2 than they emit throughout their lifetime. It is very natural that the constructed environment becomes a CO2 sink as it is the largest volume of man-made material,” says Tapio Vehmas, CEO of Carbonaide.

“Avoiding carbon dioxide emissions should always be the primary mechanism to foster biodiversity. However, carbon capture and permanent storage of unavoidable CO2 emissions are needed to enable a sustainable carbon cycle, e.g., in the Waste-to-Energy sector. Carbonaide technology is an excellent example of how to both reduce and utilize existing CO2 in new products and permanently store carbon from the cycle," says Matti Wallin, Business Director from Vantaa Energy Ltd, one of Carbonaide's strategic investors.

Addtional examples for carbon capture and storage solutions include Carbicrete, CarbonCure, CarbonBuilt, and others. 

  • EPA's removal of the proposed emissions limit from the Good Neighbor FIP

The PCA has come forward in support of the U.S. Environmental Protection Agency's (EPA) decision to remove the proposed emissions limit from the Good Neighbor Federal Implementation Plan (Good Neighbor FIP). The rule would have required cement kilns to meet emissions standards for nitrogen oxides (NOx) more stringent than new kilns, forcing cement plants to curtail production or shut down. 

According to PCA's March 15 press announcement, the EPA had relied on flawed data. This also was the first time they included cement manufacturers among other industrial industries subject to the proposed rule, despite many cement plants already utilizing emissions control technology. 

"The rule would have been regulatory overkill for America's cement manufacturers as they have spent hundreds of millions of dollars implementing state-of-the-art emission technology controls to comply with stringent NOx and other air emissions requirements," says Sean O'Neill, PCA's Senior Vice President of Government Affairs.

He adds that if the proposal had been enforced, it would have slowed the progress of construction projects funded by the Bipartisan Infrastructure Law. The PCA has said that they continue to will evaluate the ramifications of the final rule and work with the federal government to meet its obligations to protect air quality.

  • More integrated data at your fingertips

More and more integrated software systems are now available to help contractors watch tool and equipment use. Data like telematics, GPS, and fuel efficiencies can provide insight so the job can be done with that much more efficiency and productivity. 

One example of these decision-making tools is the Enviromix Impact Tool, an online tool from Chryso Group designed to help contractors with EPD data and make better/smarter decisions on how to make a better impact on the environment. The pre-diagnosis tool calculates the environmental impact of a concrete design mix. according to the Chryso website, contractors and concrete suppliers can use it to compare two concrete formulations and integrate the energy cost of heat curing as well as the carbon impact of the distance of raw material transportation.

Launched during CONEXPO/CON-AGG 2023, the Enviromix SE strength enhancer reduces the cement factor by approximately 10%. According to Saint-Gobain, the admixture activates the hydration of cement and SCMs and enhances early and late age strengths, up to 1,000 PSI at one day. 

The company committed to net-zero back in 2019 signing the pledge of the Global Compact "Business ambition for 1.5° C". Beforehand, Saint-Gobain (one of the companies within Chryso Group) already committed to reducing its CO2 emissions by 20% between 2010 and 2025. Various programs and tools had been implemented in order to support this target.

Further, Giatec updated its concrete sensor to provide contractors intelligence and savings. Designed in parallel to the Giatec SmartRock maturity sensor, the SmartRock Pro takes fluctations in stride and self-calibrates to the concrete mix to cut costs, save time, and fight construction waste from break tests. Contractors only need to tag the sensor, install, and start measuring concrete strength in real-timepotenitally saving multiple days per placement. 

“On a construction site, you never know what changes will come your way; from weather conditions to scheduling, even down to last-minute changes in your mix order and delivery,” says Aali Alizadeh, CTO and Co-Founder of Giatec. The addition of new self-calibrating concrete strength monitoring sensors to Giatec’s existing advanced AI solutions provides general contractors and concrete producers with a superior solution ecosystem that cuts cost, saves time, and produces less waste from break tests, while reducing significant GHG emissions resulting from concrete production. 

  • Research says the adoption of a "circular cement value chain" has the potential to decarbonize 80% of all cement and concrete emissions by 2050

A report by McKinsey & Company (March 2023), a global management consulting firm, promotes the idea of a ciruclar economy of concrete and cement, which "could produce €110 billion ($119.30) in net value and avoid or mitigate 2 billion tons of CO2 emissions by 2050. The report reveals that recycling and re-using construction materials and minerals alone will add nearly €80 ($86.69) billion of annual EBITDA while reusing concrete modules and structures will drive an estimated €24 ($26.01) billion of net value by 2050. 

“Applying circular economy principles to cement and concrete would not only help decarbonize the built environment but generate enormous economic value," says Jukka Maksimainen, global co-leader of McKinsey’s Global Energy & Materials practice. "The cement industry is perfectly positioned to create closed loops for CO2, materials and minerals, and energy." 

According to Sebastian Reiter, Partner at McKinsey's Global Energy & Materials, research shows that that technologies utilizing CO2 such as curing ready-mix or precast concrete can create positive economic value at carbon prices of approximately €80 percent of CO2 while using construction waste as aggregates for concrete production avoids landfill costs. They add that “the total value at risk from rising CO2 prices and landfill costs could reach approximately €210 billion by 2050 and this will significantly accelerate uptake of circular technologies."

This circular economy within the cement and concrete industry connects directly with the continued advancement of machinery designed for the recycling of waste materials, making crushing equipment smaller for easier transporation and use at the jobsite. For example, debuting for the first time in the U.S. at CONEXPO/CON-AGG 2023, McLanahan brought RubbleCrusher to launch its compact, mobile crushing units to the U.S. construction market. 

RubbleCrusher showcased its portable and track-mounted jaw crushers. Fast to deploy on job sites and meet all Department of Transportation regulations, the popular pull-behind portable crusher, RC150V, can be hauled by any full-size pick-up truck, simplifying setup at any operation. The RC150V unit weighs just under 7,800 lbs. and enables the operator to recycle construction and demolition waste materials for use on site, without having to pay to remove materials or bring in new aggregate for jobs. The RC150T offers the same features as the RC150V but is mounted on tracks, making mobility on site possible by remote control.

The Work Continues

The industry's not done yetnot by a long shot. The global goal is to reach carbon neutrality by 2050 and that includes everything from the efforts at the plants all the way to the equipment purchased to build. Contractors have some levels they can pull themselves.

PCA launched cementprogress.com to provide a resource for sustainable solutions and actions. The experts on the site include a few ideas for contractors to consider in reducing their own emissions at the jobsite:

  • Source local materials to reduce transportation emissions
  • Replacing raw materials with recycled materials
  • Choosing lower-emissions or electric vehicles and equipment
  • And more (find additional suggestions within the /join-us section)

To take advantage of these opportunities, McKinsey suggests contractors should embrace digital marketplaces for waste materials, using technologies that facilitate design and standardization and creating customer-centric circular economy businesses.

The examples presented are not the only wins in the industry. With as many innovations presented during CONEXPO/CON-AGG, World of Concrete, and other major construction tradeshows so far this year, one can only anticipate what is just beyond our horizon. 

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