Mathematical modeling of heat recovery from a rotary kiln

In this study, heat recovery from rotary kiln was examined for a cement plant in Turkey. At first, an exergy analysis was carried out on the operational data of the plant. Results indicated the presence of 217.31 GJ of waste heat, which is 51% of the overall heat of the process. Then a mathematical model was developed for a new heat recovery exchanger for the plant. It was determined that 5% of the waste heat can be utilized with the heat recovery exchanger. The useful heat obtained is expected to partially satisfy the thermal loads of 678 dwellings in the vicinity through a new district heating system. This system is expected to decrease domestic-coal and natural gas consumption by 51.55% and 62.62% respectively. CO2 emissions may also be reduced by 5901.94 kg/h and 1816.90 kg/h when waste heat is used instead of coal and natural gas.