Opting of an Organic Rankine Cycle Based on Waste Heat Recovery System to Produce Electric Energy in Cement Plant

Abstract

This study investigates the feasibility of installing a waste heat recovery system (WHR) in a cement factory in Iraq using the organic thermal Rankine cycle (ORC). Heat losses in the cement industries represent high energy consumption percentages of the total energy inputs. The production of clinker is a sub-process in the cement manufacturing plant and consumes three quarters of the total energy used as heat from combustion. The main sources of waste heat in the cement plant are identified, from these sources of waste heat from the kiln surface to the air, hot air coming out of the clinker cooler, and preheating exhaust gases. It is possible to obtain the total waste heat from these sources in the range of 35-40% of the total heat input. This waste heat energy can be exploited by installing a waste heat recovery system in these plants to generate electricity. It is possible to generate electrical energy by 5.9 MW. When using an organic system to recycle hot gases in plants whose daily production is up to 6000 tons, the installation of such a system could lead to saving 82.5 tons of fuel oil consumption per day, and reducing carbon dioxide emissions by 99.12 tons per day.