Operating Conditions of Incinerator of Rotary Kiln
Posted Nov 01 2012 5:52am
Usually, the cross-section of the rotary kiln is divided into two parts, namely the free space and the solid material pellet bed. In the tumble mode, the solid material pellet bed can be divided into the upper active layer and the lower passive layer close to the wall surface of the rotary kiln, which is also called the plug flaw region. Under the lower part of the material bed, the material particles in the passive layer almost have no relative motion. The material particles only do the circular movement upward with the motion of the rotary barrel in fixed radius and the radial position. There will be no axial displacement and the radial diffusion. With the effect of the gravity of the particles in the upper active layer, the particles fall on the lower part of the surface of the material layer from the high end of the material layer in the form of the rolling. In the rolling process of the active layer, there will be random mutual collision between the material particles, which will consume part of the energy and also cause the axial mixing and radial movement of the solid material particles. The radial mixing plays very import role in the heat and mass transfer and the reaction of the materials, while the movement in the axial direction directly affects the average residence time MRT of the material particles in the rotary kiln. Therefore, the study on the axial direction of the particles becomes the focus of the average residence time of the solid material particles in the rotary kiln. In actual use, the incinerator of the rotary kiln for the dangerous waste is in low filling rate. In such conditions, the average residence time of the material particles in the rotary kiln is inversely proportional to the axial speed of the material particles in the rotary kiln. The rotating speed of the rotary kiln is inversely proportional to the dip angle. When the filling rate is lower than 10%, the average residence will not be affected.