Experiences with the fls calciner at the lengerich plant

Abstract

The present article describes our experience with the new kiln line 8 at the Dyckerhoff Zement GmbH Lengerich works. The emphasis here is on the design and operation of the calciner and NOx reduction, and on general operating experience with the kiln system and the emissions level. The main components of the kiln system are a 6-stage, double string calciner from the company FLS with LP cyclones for a low pressure drop, an internal low-NOx calciner, a Rotax 2 rotary kiln and an IKN cooler. In Table 1, the essential operating data of the kiln system, which were determined by the Research Institute of the Cement Industry (FIZ) by measurements during operation, are summarised. The maximal clinker production of 3,750 t/day is somewhat higher than the guaranteed 3,700 tons per day. With a mean dust content of 70 g/m3 in the preheater waste gas and a pressure drop of 51 mbar over the whole heat exchanger, the guaranteed values are reliably maintained. At 3,044 kJ/kg clinker, the specific thermal energy consumption of the whole kiln system is about 1 % below the guaranteed value and the specific electric power consumption adds up to 6.9 kWh/t clinker for kiln main drive and waste gas blower.