| The process problems existing in the alumina clinker sintering system of Zhongzhou Branch were investigated in this paper. some measures were taken to optimize the process. Some technical problems including annular slurry scale of the rotary kiln tail, short period of the sintering belt liner, the formation of the kiln scale skin under high temperature and its maintenance had been solved. As a result, the capacity and operation rate of the kilns were increased.Firstly, by studying the clinker sintering characteristic in laboratory, the better process control conditions for hi-temperature kiln scale skin formation in the intensified sintering process were the clinker sintered temperature 1240~1300℃ and bulk specific gravity of the clinker 1.0 ~1.4.Under the above condition, the quality and thicker kiln scale skin can be obtained.Secondly, compared with the performance and practical application of different types of the coal powder burner (In the alumina clinker sintering system of Zhongzhou Branch) , it indicated that the single air duct pulverized coal burner is suitable for the alumina clinker production of Zhongzhou Branch. The parameters of the pulverized coal injection pipes in different stages have been optimized on the basis of theoretic analysis and industrially experimental data.Lastly, based on testing varied kiln tail spray guns, the new feeding way—regular triangle type three spray guns were proposed. After above improvement, the kiln operation was stable and the capacity of the kiln was raised. Based on practical study, the control index of the slurry pressure 1.6~1.8MPa, the spray gun diameter 16~17.5mm and the change of temperature of the kiln tail 220~245℃. By taken above measures, the problems such as the annular slurry scale of the kiln tail heat exchanger, the increasing negative pressure and low capacity were resolved.By using the new technology, the capacities of the existing six kilns were increased more than 100,000 alumina tons per year and the economicefficiency was increased significantly. |
