How to deal with excessive dust levels in fuel and gas boilers as well as oil gun misfire
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The boiler operates at around 30% load. Six oil-gas dual-purpose burners are installed on the front wall; three of these burners are ignited using compressed air for atomization. The oil supply rate is 2.3 t/h, while the air supply volume is 40,000 cubic meters. The oxygen content in the superheater is 4%. After increasing the oil supply rate to 2.5 t/h, high dust levels were detected at the rear of the boiler, and the flames from the oil burners resulted in longer exhaust smoke. After increasing the pressure of the air used for atomization in front of the gun to 0.45 MPa (with an oil pressure of 0.35 at that time), the flame’s smoke was reduced and its length shortened; however, the combustion in the oil gun became unstable and the flame went out. Reducing the opening degree of the secondary air valve by 1/3 improved the situation regarding flame outages, but when more fuel oil was added, the dust levels rose again. The current question is: High dust levels are likely due to oxygen deficiency or problems with atomization. Increasing the atomization pressure causes the oil gun to experience flame outages, while reducing the atomization pressure and closing the secondary air valve prevents flame outages but deteriorates the combustion process. It’s easy for dust levels to exceed the limits when the load is increased
I’m waiting online for the experts to give some answers, thank you
The pressure for atomization is too high.... Remember, the primary air is used to regulate oxygen supply, while the secondary air is used to control the shape of the flame. In fact, the air consumption can be roughly calculated; you can look up the oxygen content required for complete combustion in such cases, and multiplying that by 5 gives an approximate value for the air needed.
The nebulization isn’t good to begin with; the nebulization pressure should be low, right? But the flame goes out when the atomization pressure is increased; I’m wondering if the reason is that the high pressure prevents the oil from being sprayed in So the fire separation is worse? Why does high nebulization pressure extinguish the fire? My furnace temperature is also normal
Is your fuel oil heated before it enters the burner? Is it the fact that as the temperature drops, the viscosity increases which leads to poor atomization, and then you increase the atomization pressure even further, raising the pressure in the mixing chamber and resulting in improper fuel mixing?
High dust levels are usually due to poor combustion; try increasing the primary air flow, using steam for atomization, and raising the furnace pressure.
Does \"fuel primary air\" refer to the atomizing air? The oil gun can only adjust the atomizing air and secondary air valves; there is no such thing as primary air
The weather in Guangdong isn’t that cold yet; the heating system for the fuel oil pipelines has never been activated. Heavy aromatic diesel is being used, and its viscosity is not high. The medium used for atomization is not mechanical atomization either; why does defocusing occur regardless of whether the atomization pressure is high or low? What are the main factors that affect devitrification? How can it be adjusted from a operational perspective? Thank you
https://bbs.hcbbs.com/thread-870643-1-1.html There are relevant articles on the forum that can be used as a reference.
All of the above analyses are correct; this might be caused by a defect in the gun itself, perhaps an issue with the nozzle?