Wouldn’t it be great if there was a way to improve the quality of the products you manufacture, future-proof your factory and source a new revenue stream, all while helping save the environment?
KRAFT can make this possible.
The cement industry is one of the two largest producers of carbon dioxide (CO2), creating up to 8% of worldwide man-made emissions of this gas. If cement was a country, it would rank number 3 in carbon emissions globally.
CO2-emissions do not only effect the planet, but have also started costing money. Companies are being incentivised to lower their emissions by being required to buy „emission-rights“ in the form of certificates, of which only a certain number will be given out or sold each year.
(to learn more about emission-rights visit https://ec.europa.eu/clima/policies/ets_en)
So, while cement manufacturing is responsible for a large portion of CO2 emissions, the product in which it’s used, concrete, is irreplaceable.
During its service life, concrete acts as a sponge, taking in large amounts of CO2 from the atmosphere. Atmospheric CO2 entering concrete is a natural reaction between products of cement hydration and carbon dioxide called weathering carbonation. It is a slow naturally occurring process.
Not only does this take the strain of dangerous greenhouse gases out of the atmosphere, concrete also benefits from the intake of CO2.
When CO2 is introduced into a controlled concrete curing environment within a chamber at the early stages of curing it is called curing carbonation.
Curing carbonation is part of an accelerated curing process that injects carbon dioxide into the chamber, where the concrete elements are cured. The CO2 is absorbed in the fresh concrete under low pressure.
PROFITING FROM CO2 CONCRETE CURING
During the CO2 curing process, the CSH-gel in concrete and the products of hydration react with CO2 increasing the production of calcium carbonate in the capillaries at and near the surface of the concrete products. A benefit of using this method is the formation of the insoluble compound CaCO3, which creates a less permeable, denser surface with harder corners and edges. CO2 absorption can be tested with the use of a diluted Thymolphthalein solution, which, when in contact with high ph levels, turns blue. As seen in the photograph, CO2 has penetrated further on the right concrete paver.
Water saturated with calcium hydroxide migrates through capillaries to the surface of concrete products and then reacts with atmospheric CO2 to form calcium carbonate, the primary component of efflorescence.
When CO2 is instead introduced during the curing process, calcium carbonate is formed within concrete’s capillaries, preventing water from being absorbed into the concrete, as well as preventing water from condensating out of the product.
This significantly impacts the quality of the end product. If no water permeates in or out of the concrete product, no efflorescence can take place.
As ways are found to capture and store CO2 emissions, the need to find a safe and useful way to sequester stored carbon dioxide, grows. With the „cap and trade“ market becoming more competitive, the trading of stored CO2 between „emitters“ and „users“ will soon be prevalent. Emitters will have the opportunity to lower their emissions and trade their emission certificates.
„Emitters“ will pay concrete producers who use CO2 curing to take their stored CO2 and sequester it, allowing for a potential revenue stream.
While there is a big push to develop a cement whose manufacture emits less carbon dioxide, a great deal of time will elapse until the cement industry brings the cement to market. In the meantime, important steps are available to use captured and stored CO2.
Let Kraft Curing future-proof your plant with an accelerated curing system, such as Quadrix® or Convect-Air®, offering the opportunity to improve product quality now and integrate a Kraft Curing CO2 dosing system when a source of stored CO2 has been secured. A CO2 dosing system is outfitted with numerous safety measures and protocols, assuring risk is minimised in the handling and operation of carbon dioxide.
Improve product quality, sequester available carbon dioxide and secure a possible revenue stream by future-proofing with Kraft Curing – all while having a positive impact on the environment, so you will have the ability to implement technology that is cutting edge now and will be state of the art in the near future.