Rotary kiln calciner temperature and fuel combustion Relations

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Calciner temperature depends on the fuel combustion process heat release rate and raw material endothermic decomposition rate. When the fuel combustion heat release rate is slow, the raw material decomposition under conditions close to equilibrium , calciner at a temperature of 860 ~ 920 ℃ range , the heat released by combustion of fuel will be quickly transmitted to the raw material, decomposition reaction was absorbed. However, when the fuel combustion rate is higher than the endothermic decomposition of the raw material rate , fuel combustion heat of the decomposition of the raw material is larger than the heat absorption , decomposition temperature of the furnace at this time will exceed the equilibrium temperature range .

From the perspective of fuel combustion , decomposition furnace fuel combustion and fuel combustion in rotary kilns have many differences . Rotary kiln fuel combustion temperature is much higher than the calciner , rotary kiln fuel combustion is obviously controlled by diffusion , Hammer crusher      while the calciner fuel combustion is different. As the temperature is much lower than the rotary kiln calciner fuel within the combustion temperature , the combustion of coal in the calciner time is affected by the impact of coal types is much greater than the rotary kiln . If FCB calciner cement volume is small, the structure also has some problems when using low volatile , high calorific value of coal ash , the reducing atmosphere is very serious, rapidly lead to clogged crust ; while the use of high volatile , low ash the calorific value of coal when the situation is improving. Fineness of pulverized coal burner for rotary kiln is very sensitive , because it is controlled by diffusion , that is transported by the rate of diffusion boundary layer control ; while coal fineness impact on the decomposition of the combustion in the rotary kiln is no within that sensitive .

Problem will come back calciner temperature and fuel combustion relationship up . Since the rotary kiln fuel combustion is controlled by diffusion , decrease 10 ~ 20 ℃ for fuel burning effect is even differentiable. But in the calciner is significantly different. If the decomposition furnace volume is small, coal burning ember lack of time , as well as reducing atmosphere heavy , which will reduce the temperature of decomposition furnace , reducing the amount of coal calciner with a view to change the incomplete combustion of pulverized coal , reducing atmosphere , but is often counterproductive. Result in diminished production of the case , reducing the calciner coal , calciner temperature decreases, the coal combustion rate decreases rapidly with decreasing temperature , combustion of pulverized coal is always incomplete . Appropriate to increase the volume of decomposing furnace has become a development trend . Calciner small difference in the case of coal , may be appropriate to reduce production , and should not reduce the decomposition temperature of the furnace .