Calcium Carbonate (CaCO3) is found in limestone, a highly versatile and one of the most abundant minerals on Earth, accounting for approximately 4% of the Earth’s crust. In addition to providing a cost-effective way to add extra calcium into consumable items such as vitamins for calcium intake and antacids for digestion, it is used to neutralize acidic compounds in a variety of contexts. Moreover, calcium carbonate derivatives are used extensively in the construction industry, the agriculture industry, and in the cement industry. Calcium carbonate also provides a viable answer to shrinking the earth’s carbon footprint.
Calcium Carbonate in the Concrete Industry
Calcium carbonate is found in three principal rock types: chalk, limestone, and dolomite (including the metamorphic rock known as dolomitic marble). Limestone and lime are the principal calcium carbonate derivatives used in the concrete industry. Calcium carbonate helps accelerate the cure rate of concrete and increases the concrete’s slump rate. Slump rate is the consistency of concrete before it sets. The higher the slump rate, the higher the concrete’s workability, facilitating a long enough work time so that it can level itself and be more easily pushed, molded, and smoothed out like a laying a floor. In certain applications, such as forming a curb or plastering a pool, a lower slump rate is desirable so that the concrete will set more quickly. In these cases, calcium carbonate would not be added to the concrete mixture. Green strength describes a cast product’s ability to withstand handling, mold ejection, and machining before it is completely cured. Calcium carbonate helps increase concrete’s green strength. It also improves concrete’s particle packing, provides concrete with a spacer effect, and promotes self-compacting properties of concrete. In addition, calcium carbonate reduces porosity and air void in concrete which improves pumpability and adds to smoother surfaces. Calcium carbonate can be used as a filler in Portland cement, reducing the product’s high cost.
Calcium Carbonate’s Contribution to Reduction of Carbon Imprint
Approximately 8 to 10% of global anthropogenic CO2 emissions are produced by cement industries, and cement production is projected to exceed 6 billion metric tons by 2050. These facts are a cause for global concern. In response, the cement industry utilizes Supplementary Cementing Material (SCM), where a portion of cement is replaced with supplementary cementing material such as fly ash, ground granulated blast-furnace slag, silica fume, and limestone powder. Since the 1930s, the most widely used SCM is fly ash. Fly ash is economical, environmentally friendly, easily available, and improves concrete in many ways. Unfortunately, the future availability and quality of fly ash is a current concern due in part to EPA regulations limiting compounds found in fly ash, SOx, NOx, and mercury. Compared with fly ash and several other SCMs, calcium carbonate (CaCO3) is cheaper and can be blended within standard cement. There is evidence that replacement of cement by just 2% CaCO3 helps reduce the CO2 emission from cement plants by 69%, meeting the economic and environmental aspects of fly ash as well as contributing equal positive effects to concrete.
Noah Chemicals Formulation and Application
Noah Chemicals offers many different grades of calcium carbonate, which can be the perfect additive for your concrete mixture or any other calcium carbonate product. Noah Chemical Services can formulate a specific calcium carbonate product with advantageous characteristics to achieve your goals.
Noah Chemicals mission is to deliver innovative, high-quality, and customer-focused solutions that benefit the world’s industries. Our expert team works closely with clients to close gaps and address challenges. With 60+ years of experience, Noah Chemical can meet your calcium carbon product needs. Email our Chemical Services team directly at [email protected] or call us at (888) 291-1186 to get started.
