HEAT RECOVERY ON THE SMOKE OF THE CEMENT KILN AND UTILIZATION OF THE RECOVERED ENERGY

At CIMENTS D’OBOURG we are running two 3 000 tons per day wet process cement kilns. After the electrostatic precipitator, smoke temperature is between 120 and 150 deg.C. Its moisture content is about 0. 3 kg water per kg dry gas. Smoke enthalpy is thus about 1000 kJ per kg dry gas. Latent heat (about 850 kJ per kg dry gas) is six times higher than sensible heat. To recover this heat we need an exchanger which will condense the water vapour without getting clogged by hydrated kiln dust. Such an exchanger exists. It was invented around 1965 by Professor LEFEBVRE of the Faculté Polytechnique in Mons. He called it the “ AMAZONE” heat exchanger.