How to calcine high-quality lime in a lime vertical kiln
To calcine high-quality lime in a lime vertical kiln, it is necessary to coordinate and optimize various aspects such as raw materials, process parameters, and operational control.
High quality raw materials are the foundation. Limestone with high content of calcium carbonate (CaCO3) and low impurities should be selected. Generally, the CaCO3 content is required to be above 90%, and the particle size should be uniform, controlled at 40-80mm. This can ensure sufficient and uniform reaction during calcination, and reduce the occurrence of burning and overburning.
Precise control of process parameters is the core. The calcination temperature should be strictly controlled at 1050-1150 ℃. If the temperature is too low, the limestone will not decompose completely, resulting in raw combustion; If the temperature is too high, the lime grains will grow and the activity will decrease, resulting in overburning. At the same time, the air volume should be reasonably controlled to ensure that the gas and air are fully mixed and burned, providing a stable heat source for calcination. The calcination time cannot be ignored, usually taking 8-10 hours to completely decompose limestone.
Standardized operations are equally crucial. The fabric should be uniform to avoid deviation from the kiln and ensure a balanced distribution of heat inside the kiln. When discharging ash, a continuous and uniform method should be used to prevent excessive pressure and temperature fluctuations inside the kiln. In addition, regular maintenance and repair of the kiln body, timely replacement of damaged refractory materials, ensure good sealing and insulation of the kiln body, and create a stable environment for the calcination of high-quality lime.
