What is the division of each working zone of the new dry process cement kiln?

      Under normal circumstances, according to the temperature of the material in the cement kiln, the working zones of the rotary kiln system (including the kiln tail preheating and the kiln head cooler) are divided into the following types: drying zone, preheating zone, decomposition zone, exothermic zone Reaction zone, firing zone and cooling zone.

      Drying zone: For the traditional cement rotary kiln, the material temperature in the drying zone is 20-150℃, and the gas temperature is 250-400℃. For the new dry process cement kiln, the material entering the kiln is heated to above 150°C the moment it enters the I-level cyclone at the end of the kiln. Therefore, the drying belt is only a short section at the entrance of the raw meal. In the kiln tail system of the new dry process cement kiln, there is almost no drying zone.

      Preheating zone: For traditional cement rotary kiln, the material temperature in the preheating zone is 150-800℃, and the gas temperature is 450-850℃. For the new dry process kiln, from the first stage to the last stage of the cyclone is the preheating zone. In the preheating zone, the organic components in the raw meal begin to dry and decompose, and the clay begins to dehydrate, creating conditions for the decomposition of calcium carbonate.

      Decomposition zone: For traditional cement rotary kiln, the material temperature in the decomposition zone is 800-1000℃, and the gas temperature is 1000-1400℃. For the new dry process cement kiln, from the precalciner to the kiln 7D away from the kiln head (D is the diameter of the steel plate of the kiln) is the decomposition zone. For example, when the size of the rotary kiln of the new dry process kiln is φ4×60m, 28-60m from the kiln head is the decomposition zone; when the size of the rotary kiln of the new dry process kiln is φ4.7×74m, 33 meters from the kiln head -74m are all decomposition zones.

      Exothermic reaction zone: also called transition zone or upper transition zone, the material temperature of the exothermic reaction zone is 1000-1300℃. For the calculation of the new dry process cement kiln, the 7D to 4D calculated from the kiln head are all transition zones. Taking the new dry process cement kiln of φ4×60m as an example, from the kiln head, 16-28 meters are the transition zone; taking the new dry process cement kiln of φ4.7×74m as an example, it is 19-33 meters from the kiln head for the transition zone.

      Cooling zone: The temperature of the kiln material in the cooling zone is 1100-1300°C. After the clinker exits the firing zone, it is cooled or solidified in the cooling zone.