Energy Audit and Heat Recovery on the Rotary Kiln of the Cement Plant in Ethiopia: A case study

This study deals with the energy audit and heat recovery on the rotary kiln taking a cement factory in Ethiopia as a case study.The system is a dry type rotary kiln equipped with a five stage cyclone type preheater, pre-calciner and grate cooler. The kiln has a capacity of 2,000 tons/day.Mass and energy balance has been performed for energy auditing. The energy lost from the kiln shell is about 4.3 MW. By using secondary shell on the rotary kiln about 3.5MW could be recovered safely.This energy saving reduces fuel consumption (almost 9%) of the kiln system, and increases the overall system efficiency by approximately 2–3%.