The cement factory in Wildegg in Switzerland
Dürr Systems
The Jura-Cement-Fabriken in Wildegg, Switzerland, use the first regenerative thermal oxidation system (RTO) in the country. The solution combines Dürr’s Ecopure RTO multiple-chamber principle with an optimization of the existing process technology in the calciner.
The new technology enables a reduction in the use of traditional raw materials along with compliance with future limit values. Through the planned substitution and the increased use of excavation materials from demolitions, the solution makes a contribution to the circular economy. Once the new system goes into operation in 2022, lower clean gas values for carbon monoxide, hydrocarbons, and ammonia (NH3) will be achieved. It is more than 20 years since Dürr supplied the first RTO for a cement plant in the USA.
For the project in Wildegg, a new concept has been developed, verifying it in appropriate preliminary tests. A crucial step here is optimizing the existing plant technology as well as reliably reducing emissions with the downstream RTO. A concept like this is revolutionary in the cement industry. Instead of combining selective catalytic reduction (SCR) and making compromises to the RTO, this solution is based on the interaction of two separate process steps: on the one hand, the existing plant is optimized with regard to reducing NOx and, on the other hand, the CO and VOC emissions are reliably removed in a specially designed RTO. Separating the processes reduces complications developed from combining the steps, which increases functional reliability.