eLCC – A new solution for calcined clay
A significant contribution to the decarbonisation of cement production is being made, with new types of cement which use calcined clay and a smaller proportion of clinker than in traditional cement manufacture. Clay calcination requires lower burning temperatures than clinker production, so the carbon footprint of the cement is reduced significantly. Almost 4 years ago, Aumund teamed up with Holcim on a common project for the electrical calcining of clay on an Aumund pan conveyor.
Aumund, with its 27000 references located in plants around the world, has been a trusted partner of Holcim for decades. As a leading supplier of conveying and storage technology solutions, Aumund has expertise in conveying bulk materials at temperatures of up to 1000 °C.
The design phase for the electrical Linear Calcination Conveyor eLCC culminated in the construction of a demo version at the Aumund Fördertechnik headquarters in Rheinberg in Germany, and initial calcination tests were carried out with encouraging results.
Thermal activation of the clay is achieved efficiently with the combination of radiant heat and material circulation on the conveyor, which is completely enclosed and insulated. This reduces the energy requirement compared to other solutions, and the volume of the heating chamber can be kept very compact and relatively small.
The design significantly reduces possible heat losses and allows the system to heat up and start up quickly, which offers great flexibility to plant operators.
As the system is based on the robust Aumund pan conveyor it benefits from the proven durability of the equipment technology. A further advantage is the modular design which allows production capacities to be increased at any time by extending the equipment.
Other heating systems such as ceramic gas burners could be installed instead of electrical heating elements, but electrical heating elements can be powered 100% by renewable energies such as wind or solar power, so that the calcination process can be completely carbon-neutral, with no CO2 emissions generated.
The first complete industrial plant for this process will be constructed in 2025.
