As we move into the 21st Century there is increasing concern about the environmental impact of Portland concrete production. Inclusive of carbon dioxide (CO2) emissions, the handling of kiln dust (CKD), the emission of trace metals including mercury, as well as smaller quantities of other greenhouse gases such as Nitrous Oxide (NOx), Sulfur compounds, and Methane Gas calcining limestone is releasing into the atmosphere. The production of 1-ton of limestone-bonded Portland concrete is reported to emit approx.. 0.87 tons of CO2 into the atmosphere, along with the other harmful emissions. https://en.wikipedia.org/wiki/Environmental_impact_of_concrete
While CO2 emissions emanate from the calcination (high heat firing) of limestone, the additional toxic emissions are due to the combustion of the fossil fuels. In the United States the production of Portland concrete accounts for more than a hundred million tons of waste carbon dioxide, about 2% of our manmade CO2 emissions. Globally, the Portland concrete industry produces approx. 1.6 billion tons of CO2 – exceeding 8% of the total CO2 emissions from all human activities. Due to increased awareness of these facts, it's also important to note that the world concrete industries seriously want to reduce all forms of toxic, earth polluting emissions.
Even though useful results have been limited, the most ambitious attempt to reduce CO2 emissions occurred when world governments provided carbon credit financial rewards that were welcomed by the already non-carbon polluting industries. In this context, our global government supported CO2 reduction strategies are focused on reducing rather than eliminating harmful Portland concrete emissions. While carbon credit financial rewards have dramatically helped numerous industries pull in billions of dollars, Tesla electric cars being a prime example, carbon credit incentives have not reduced the Portland concrete pollution issues.
Current Portland concrete industry carbon reduction strategies include installing more fuel-efficient kiln technologies, substituting non-carbonate sources of calcium oxide within the kiln-firing of raw materials, and using recycled aggregates. Valiantly trying to overcome the adverse production / end-user problems due to the corrosive, acid susceptible, low strength realities inherent within the alkali-based chemistry that occurs when calcined limestone is blended with gypsum, toxic fly ash, various mineral aggregates, and water-activated into artificial stone.
The basis of traditional Portland concrete was invented in Leeds, England by Joseph Aspdin in1824 using limestone obtained from the near-by Isle of Portland. At that time Aspdin’s kitchen calcined (fired) limestone concrete was impressive. It was relatively easy to produce and use as a water-activated, artificial rock material that could be slurried, hand stirred, and formed into multiple construction / building products. To overcome the low compression / flexural strength eventually metal rebar was inserted. Allowing Aspdin and later on his son William's Portland concrete inventions to create the foundations of our modern world.
From that historic perspective, over the past two-hundred years limestone-bonded Portland concrete has revealed a litany of infrastructure, construction, building, metal rebar corrosion problems. Primarily due to the alkali chemistry inherent in limestone-bonded Portland concrete admixtures. While the concrete / construction industries have spent decades and $100’s of millions actually billions trying to improve traditional Portland concrete, the crumbling, cracking, durability problems remain a serious problem.
Inclusive of Portland concrete material safety data sheets (MSDS) listing a range of health hazards. Including the caustic, alkali chemistry being detrimental to wildlife. With fish and aquatic creatures especially vulnerable to the caustic pH water changes from the toxic runoff that emanates from road building/repair and construction operations. While the obvious solutions to remove concrete pollution include (1) reducing the use of limestone-bonded Portland concrete, which is impractical given the massive worldwide need, (2) improving Portland concrete chemistry into non-toxic, eco-safe formulas, and (3) recycling CO2 emissions into carbon activated energy systems. With numerous carbon capture projects currently in advanced stages of development. https://www.climatecentral.org/news/first-commercial-co2-capture-plant-live-21494
Another fact to consider: Traditional Portland concrete formulas are not going to go away anytime soon. Therefore, it's essential that the raw materials used in Portland concrete are replaced by eco-friendly, non-toxic versions. In studying these issues, a variety of chemistry issues underpin Portland concrete’s environment related problems. Even though the Portland concrete industry has supported decades of research to improve limestone-bonded concrete, few if any worthwhile results have been achieved.
Nonetheless, these expensively enacted research efforts have convinced the competitive concrete industry that it has done and continues to do everything it can to improve limestone-bonded Portland concrete. Inclusive of lauding the use of ‘coal-fired’ fly ash as a “recycled green material"? Ignoring the fact that coal-fired fly ash contains serious toxins, including radioactive ingredients. https://www.scientificamerican.com/article/coal-ash-is-more-radioactive-than-nuclear-waste/
With these concrete facts shared, environmental issues continue to be a serious problem for the global concrete industries and the world our children are inheriting. Inclusive of the Earth Summits in Rio de Janeiro, Brazil, Japan, and Germany in the 1990’s emphatically agreeing that the continuing release of concrete produced greenhouse gases was no longer environmentally and socially acceptable. And the 2015 Paris Accord initiating a variety of protective concrete industry regulations to reduce harmful atmospheric emissions. While the object of these environment protection policies was to significantly reduce CO2 greenhouse gas emissions by the year 2030, as 2024 unfolds there has been little to no evidence of improvement.
Because the production of Portland concrete is vital to our global building, construction needs, if the concrete industry continues to ignore the immediately available phosphate-bonded concrete solutions this report is about to share, the use of 19th Century limestone-bonded concrete will remain a major environmental concern. Illustrating the need for all government agencies charged with reducing concrete pollutants to widen the scope of their concrete investigations to include the superior quality, eco-friendly, durable benefits of the chemically-bonded phosphate ceramic concrete formulas that have emerged in recent times.
Significantly improved versions of Portland concrete conveniently produced and applied using conventional Portland concrete production / application technologies. Phosphate-bonded concrete that U.S. Government / Argonne National Lab studies have determined the calcining of magnesium reduces the emission of carbon dioxide (CO2) by 40% compared to the calcining of the limestone used in Portland concrete. Creating an evolved form of PortlandCeramic concrete that provides user-friendly, water-activated, non-toxic, science validated, carbon credit worthy concrete / asphalt repair, construction, homebuilding, decorative, radiation shielding benefits.
With this information shared, due to the massive global need for concrete the toxic runoff, environmental problems inherent in 19th Century Portland concrete will remain problematic into the foreseeable future. Unless...., the chemically-bonded ceramic cement formulas this report identifies are finally recognized by the world concrete industries as the long awaited, eco-safe, user-friendly, water-activated, high strength, durable, problem-solving, cost-effective, carbon credit worthy, conveniently produced and applied using Portland concrete production / application technologies, 'evolved' PortlandCeramic versions. https://www.hindawi.com/journals/isrn/2013/983731/
Not to replace and instead improve the use of Portland concrete by widening the earth-friendly scope of our global concrete needs. Backed up with decades of U.S. Government / global academic studies scientifically confirming that phosphate-bonded PortlandCeramic concrete improves and removes the toxic-laden problems inherent in limestone-bonded Portland concrete.
Report submitted by Judd Hamilton - Ceramic Cement Corporation (C3) Chairman / CEO