What are the disadvantages of burning natural gas in lime vertical kilns
There are multiple drawbacks to burning natural gas in lime vertical kilns, and so far, there is no good technology to avoid these drawbacks. Lime vertical kiln burning natural gas is due to the scarcity of smokeless coal resources in many countries and regions, where natural gas is relatively abundant.
1. Natural gas burns quickly
Natural gas burns quickly and releases concentrated heat, which can easily lead to uneven calcination, with some areas overheating and others burning raw. The flame is also difficult to control and adjust.
2. Poor penetration of natural gas flames
In some large diameter lime kilns, natural gas flames cannot fully penetrate. Causing the area close to the burner to burn, but the lime in the center cannot be burned by the flame, which can also cause the problem of over burning. In this situation, the inner diameter of the kiln is limited. Lime kilns with small diameters can still be calcined with natural gas. Once the kiln diameter exceeds 3 meters, it cannot be fully burned. Generally, in order to evenly produce lime when burning natural gas, the inner diameter of the vertical kiln is less than 3 meters, which limits the production capacity of lime. Currently, with a daily output of 100 tons of gas fired lime in a vertical kiln, calcination is still feasible. Double chamber shaft kiln burning natural gas can achieve high production capacity, but the cost is over 30 million yuan, which is difficult for small and medium-sized enterprises to accept.
3. High natural gas prices
The price of natural gas is relatively high, and the thermal efficiency during combustion is low, resulting in a significantly higher energy cost for calcining one ton of lime than using traditional coal. In addition, the cost required for natural gas combustion is much higher than that of anthracite and coking coal, resulting in a significant increase in overall calcination costs.
