Model predictive control of the calciner at Holcim’s Lägerdorf plant with the ABB Expert Optimizer Modell-prädiktive Regelung des Calcinators im Holcim Werk Lägerdorf mit dem ABB Expert Optimizer

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 calciner is an endothermic process for which some of the requisite heat is obtained from the sensible heat in the rotary kiln exhaust gases but the majority comes from the combus­ tion of the (alternative) fuels fed into the calciner. In Kiln 11 at Lägerdorf up to 70 % of all the heat needed for clinker produc­ tion is provided by the fuel fed into the calciner. The calcined Summary: Successful control and stabilization of the calciner is heavily dependent on the representation of the pro­ cess characteristics in the control concept. ABB has an effective instrument for controlling such complex processes in the form of the Expert Optimizer system. The use of the Expert Optimizer reduces the variability of the process and allows it to operate under more favourable process conditions. A description is given of the results of the successful commissioning of the calciner control system at the Lägerdorf plant belonging to Holcim (Deutschland) AG.