Post-consumer carpet represents a high volume, high energy content waste stream. As a fuel for co-firing in cement kilns, waste carpet, like waste tires, has potential advantages. Technological challenges to be addressed include assessing potential emissions, in particular NO emissions (from nylon fiber carpets), and optimizing the carpet feed system. This paper addresses the former. Results of...

1 The process at Holcim's Lägerdorf plant Objective: calciner temperature control There are many different recognized plant designs in cement production. Almost all the more recent energy­efficient plants now have a suspension preheater with several cyclone stages and a calciner in which the calcination (CaCO 3 → CaO + CO 2) of the raw meal takes place. Calcination of the raw meal in the calcin...

60 1 Der Prozess im Holcim Werk Lägerdorf. Aufgabenstellung: Calcinatortemperaturregelung. In der Zementproduktion sind viele verschiedene Anlage­ konzepte bekannt. Fast alle neueren und energieeffizienten Anlagen haben heute einen Schwebegas­Vorwärmer mit meh­ reren Zyklonstufen und einen Calcinator in dem die Entsäue­ rung (CaCO3 → CaO + CO2) des Rohmehls stattfindet. Die Entsäuerung des Rohm...

The reduction process inside the ore pre-reduction rotary kiln involves a series of physicochemical reactions, and in-depth understanding behavior is helpful to improve product quality productivity. This paper reports three-dimensional steady state mathematical model based on computational fluid dynamics, which considers heat transfer, mass transfer chemical reactions kiln. A user-defined funct...

The benefits of using alternative fuels (AFs) in the cement industry include reduction of the use of non-renewable fossil fuels and lower emissions of greenhouse gases, since fossil fuels are replaced with materials that would otherwise be degraded or incinerated with corresponding emissions and final residues. Furthermore, the use of alternative fuels maximizes the recovery of energy. Seven di...