What is the effect of blowing rate on the combustion of coal-fired boiler?

The air oxygen content's effect on the boiler is mainly reflected by the effect on the blowing rate. Boiler will have typical phenomena if the blowing rate is high or low.

If the blowing rate is high, the oxygen content of boiler should increase. Therefore, there may be three different situations. Firstly, the bright and dazzling flame means the sufficient combustion of fuel and large-volume surplus air in the boiler.

Secondly, if the flame temperature is low in boiler's melting slag section, the slag discharges will be impeded. At that time, if the flue gas exhausted from the chimney is light white, it means that there is too much surplus air, so the blowing rate should be lowered.

If there is carbon dioxide in the flue gas, the flue gas exhausted from the chimney will be black which means the combustible matter in fly ash increases. This situation is caused by incomplete combustion of fuel resulting from excessive primary air and poor ignition, relatively reduced second air, low blowing speed, reduced penetrating power, etc.

Thirdly, if the blowing rate is low, oxygen content will reduce and carbon dioxide will generate. The typical phenomenon is that the flame is dark yellow and the end of flame is dark. What's more, there is black and yellow smoke in the chimney or furnace. Only appropriately increasing the blowing rate can make up for the shortage of air.

Because the oxygen content is only an aspect for combustion adjustment, incorrect oxygen content will result in some effect on the combustion adjustment instead of failures. However, the blowing rate and oxygen content should be well controlled as well.