When will secondary air be put into use?
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Sometimes the boiler can operate normally without the secondary air. I would like to know when it is more reasonable to put the secondary air into use, and the ratio relationship with the primary air. Is it feasible if it is larger than the primary air?
When the primary air is not enough, of course you need to use the secondary air. However, the functions of the primary and secondary air are not quite the same. The primary air is blown in twice to improve efficiency. This is the principle.
The impact of the "normal operation", "efficient operation" and "economic operation" of the boiler on the enterprise must be considered. What LZ means is not when the secondary wind will be put into operation, but whether it will be put into operation. It is recommended to put it into operation and adjust it carefully. This post was last edited by hehe2006 on 2009-4-15 19:35 ]
The primary air is the fuel wind, which is sent out by the primary fan and then carries the pulverized coal into the boiler for combustion.； The secondary air is the combustion-supporting air. The main function of the secondary air sent by the air blower is to supply the boiler with sufficient oxygen and the tangential power required for combustion. The primary air is blown in from under the grate, and the secondary air is blown directly into the furnace. Generally, slightly larger boilers require secondary air to adjust to ensure sufficient combustion and improve efficiency.
The input of secondary air depends on the temperature adjustment. If the input is too large, the heat loss will be large. If the input is small, the combustion will be incomplete, which will waste the utilization of thermal efficiency. Therefore, the secondary air must be input, and it must be carefully distributed and adjusted.
The primary air of the boiler is sent into the boiler from the lower part of the grate, which is one of the main conditions for fuel combustion. The secondary air is fed from the top of the furnace. Its main function is to stir the aerodynamic field in the furnace. Extend the residence time of flue gas in the furnace. Full mixing of incompletely burned fuel particles and contact with oxygen. At the same time, larger fuel particles are blown down on the grate to continue burning. Reduce the incomplete combustion loss of the boiler and improve the thermal efficiency of the boiler.