Residence time and mass flow rate of particles in carbon rotary kilns

The influences of operational and structural parameters on the mean residence time (MRT) and the mass flow rate (MFR) of solids are presented on an experimental rotary kiln. Experimental results show that the increase of rotation speed and kiln slope reduces MRT and increases MFR. Also, MFR increases with increasing charge dam height. MRT increases when the rotation speed is lower than 2.0 rpm but decreases when the rotation speed is higher than 2.0 rpm with increasing dam height. Installation position of the feed pipe also has a significant effect on MFR. The product of MRT and MFR increases approximately linearly with MFR per kiln rotation at the same kiln slope.