WHR in island mode
Turkey-based Aslan Çimento AS has commissioned a 7.5MWe waste heat recovery (WHR) project designed to operate in ‘island mode’ to ensure continuous clinker production irrespective of fluctuations in supply from the national grid. By Ilyas Kabayel, Aslan Çimento AS, Turkey.
Figure 1: waste heat recovery system in a cement plant
New suspension preheater (NSP) kilns include multi-stage preheaters and precalciners to preprocess raw materials before they enter the kiln, as well as an air quenching system to cool clinker. Exhaust streams from the clinker cooler and the preheater contain useful thermal energy that can be converted into power. Typically, the clinker cooler releases large volumes of air at 250-340˚C directly into the atmosphere. Preheater kiln gases, which reach temperatures of 300-400˚C, are used to dry materials in the raw and/or coal mill and are then sent for dedusting before being released into the atmosphere.
