The coal pile temperature measurement divides the coal pile into three layers

1. Cooling layer:

The cooling layer is located on the surface of the coal pile, about 0.5 to 1.5 meters thick. The layer is in full contact with the air. Although the oxidation reaction occurs, the heat dissipation condition is good and the heat is difficult to accumulate, so the incidence of spontaneous combustion is low.

2. Oxide layer:

The oxide layer is below the cooling layer, about 1 to 4 meters thick, and has a certain oxygen supply. The heat emitted by the oxidation reaction is difficult to dissipate heat, and keeps accumulating and heating up, which in turn promotes the oxidation reaction and is prone to spontaneous combustion.

3, choking layer:

The asphyxiation layer is located below the oxide layer, so the oxygen supply is insufficient and spontaneous combustion cannot occur.

Power plants tend to store coal piles after compaction, resulting in a decrease in porosity and a corresponding decrease in the depth of the oxide layer of coal piles. According to field experience, the oxide layer is usually located in the depth range of 1 to 4 meters below the surface. From the actual situation of the coal yard, the spontaneous combustion of the coal pile also shows a very obvious local regional sudden characteristics, there are many reasons, for example, there are some coal blocks in a certain location, resulting in good oxygen supply conditions of the location; Or a location of the coal in the process of stacking damp, moisture more visible coal pile temperature importance.