Reasons for Positive Pressure Combustion in Boilers
Reasons for Positive Pressure Combustion in Boilers
Boiler positive pressure combustion refers to the situation where the flue gas pressure in the furnace of a boiler exceeds atmospheric pressure during use. Positive pressure combustion is very harmful to the safe operation of boilers. Below is an analysis and explanation of the causes and hazards of positive pressure combustion in boilers.
There are various reasons for boiler positive pressure combustion, mainly including the following situations:
1. The operation level of the stoker is low. Therefore, the sense of responsibility is poor, the cultural quality is low, and some people have no understanding of adjusting the air volume ratio of drums and induced draft fans, resulting in poor operational skills. Causing positive pressure combustion in the boiler.
2. The flue is blocked. The blockage of the flue is generally caused by the accumulation of ash or the detachment of refractory materials inside the flue. If the refractory bricks or refractory materials of the outlet flue and smoke box of the DZ type boiler fall off in the first round; Ash accumulation or refractory material falling into the convection tube bundles of SZ type boilers; Excessive accumulation of ash at the bottom of the chimney can cause blockage of the flue and result in positive pressure combustion of the boiler.
3. Boiler air leakage. Boiler air leakage mainly refers to the corrosion, wear, perforation, and damage of some observation doors, ash cleaning doors, flues, dust collectors, induced draft fans, etc. at the rear of the boiler, causing a large amount of cold air to enter and causing the induced draft fan to overload and burn under positive pressure.
4. Insufficient air volume and pressure of the induced draft fan. There are two situations where the positive pressure combustion of the boiler is caused by insufficient air volume and pressure of the induced draft fan. One is that the modification of the boiler dust removal increases the resistance of the flue gas, resulting in insufficient air pressure; Another reason is due to the corrosion and wear of the blades of the induced draft fan caused by years of use, resulting in a decrease in the air volume and pressure of the induced draft fan.
5. Increase in heating capacity. This is because the increase in heat supply exceeds the capacity of the boiler and the problem of insufficient heat supply has to be solved by burning positive pressure.