Clinker is the most important component of cement and consists of ground limestone and marl, which is fired at 1450° Celsius. The carbon from the limestone is released into the atmosphere during the burning process. This accounts for around two thirds of CO2 emissions per tonne of clinker. Some cement manufacturers replace clinker with granulated blast furnace slag or fly ash in order to reduce CO2 emissions. However, these materials are available in reduced quantities or have to be imported.
“In our latest cement JURA ECO3, we are replacing a significant proportion of the clinker with clay,” explains Emanuel Meyer, Head of the Technical Competence Centre TCC of the JURA Materials Group. “Clay is fired at half the temperature of clinker and generates two thirds less CO2 emissions. We extract the clay from our own clay pit. JURA ECO3 cement also contains the least grey energy compared to all other Swiss cements. If a concrete is produced with JURA ECO3 cement, the total CO2 emissions per m3 of concrete are approx. 20 % lower compared to building construction concretes with Portland limestone cement.“
Certified and tested
JURA ECO3 is the only CEM II/C-M (Q-LL) cement approved in Switzerland with strength class 42.5 N, externally tested and certified in accordance with
SN EN 197-5. It is approved for building construction (concrete types A-C). “The product meets the growing demand for sustainable solutions,” explains Ralf Schumann, Commercial Director Cement of the JURA Materials Group, “whether from architects or investors such as cities and municipalities, pension funds and insurance companies, for whom the carbon footprint of a construction project is playing an increasingly important role. Thanks to JURA ECO3, they can significantly improve this.”
JURA ECO3 cement is certified by ecobau as an eco1 product. It is suitable for Minergie (A-/P-)-ECO projects and fulfils the 1st priority ecoBKP/ecoDevis. With its warm earthy colour, it also sets a visual example for sustainable construction. The JURA ECO3 cement will soon be available in the KBOB* calculator. This can be used to calculate the environmental impact of one m³ of concrete of your choice.
*KBOB = Coordination Conference of the Construction and Property Bodies of Public Building Owners
In addition to a small CO2 footprint, concrete made from JURA ECO3 cement with calcined clay has a warmer colour and also sets a visual example for sustainable construction. ECAP construction site, Couvet (zVG)
Tag: Kalk
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JURA ECO3 – the visibly sustainable cement
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Revolution in descaling technology
The build-up of limescale in appliances that work with hot water is a challenge that should not be underestimated, both in households and in thermal power stations. The conventional removal of limescale deposits is often laborious and, in the case of large systems such as power plants, involves considerable costs and energy losses. Researchers at ETH Zurich have now presented a pioneering technology that has the potential to provide a comprehensive solution to this problem.
The scientists have developed an innovative limescale-repellent hydrogel coating that uses a microscopic ribbed structure to prevent the adhesion of limescale. This structure, modelled on shark scales, reduces the direct contact of limescale crystals with the surface, making it more difficult for them to deposit. Tests have shown that up to 98 per cent of limescale deposits on a surface treated in this way can be avoided.
This breakthrough in material technology is not only able to increase the efficiency of heat exchangers in power plants, but also to extend the service life and functionality of household appliances. In addition, the environmentally friendly hydrogel offers a biocompatible and chemical-free approach to limescale prevention.
The developers have deliberately chosen not to patent and have made their findings public, encouraging the application of this pioneering technology in the property sector and beyond. This openness could significantly improve the efficiency of building operation and management by providing a simple and sustainable solution to a widespread problem.
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Sika sets new standards in the recycling of concrete
According to a message from Sika , the Zug-based building materials group has "developed a new, groundbreaking recycling process for old concrete". With the help of additives, the demolition material is broken down into its components pebble, lime and sandstone. In addition, around 60 kilograms of CO2 per tonne of old concrete would be bound, writes Sika.
"In the five largest EU countries alone, around 300 million tons of old concrete are produced annually," Sika CEO Paul Schuler is quoted in the press release. "By completely recycling, up to 15 million tons of CO2 emissions can be saved."
The new process allows the complete recycling of concrete waste, explains Sika in the press release. Conventional processes, on the other hand, have only made it possible to recycle around a third of the raw materials recovered. The new concrete obtained in the reCO2ver process, on the other hand, comes close to that of new concrete in terms of quality.
According to Frank Hoefflin, reCO2ver is a unique method in the industry for recycling old concrete. "We are already working on developing chemical additives and means to continuously improve quality in order to further advance the industrialization of our technology," explains the head of technology at Sika in the message.