Low failure rate of burner in ultra-low nitrogen integrated machine
Low failure rate of burner in ultra-low nitrogen integrated machine
The FGR system on the integrated machine is sucked back into the burner by the fan of the burner. Install a pipeline to connect the flue gas outlet to the air inlet. The location for extracting smoke is generally located at the smoke exhaust outlet where the pressure is close to zero.
The intake port is usually located near the damper of the burner. Different intake ports can affect the performance of the fan operation.
In order to ensure sufficient smoke is sucked in to meet the requirements of nitrogen oxide emissions, the pipe diameter between the flue and the burner must be appropriate to reduce pressure loss to a minimum.
The overall stability of the combustion system decreases. As the FGR flow rate increases, oscillations in the furnace or flue can easily affect the stability of the combustion system through the FGR channel. Therefore, a larger FGR flow rate is not necessarily better, usually less than 25% of the total flue gas volume. It is not recommended to involve flue gas recirculation in oxygen content control, as the cross effects of combustion air, flue gas pressure, furnace, and reducing flue gas oxygen may lead to an increase in N0 emissions.
Condensation water appears at the inlet of the fan. Due to the mixing of humid and hot flue gas with lower temperature combustion air, condensation water may be generated, which may corrode the internal components of the burner. Of course, this depends on the temperature condition of the flue gas and combustion air. If necessary, insulation can be considered for the FGR pipeline, reserved condensate discharge outlet, and preheating of fresh air.
FGR will reduce the output of the burner. By installing FGR function on the existing burner, the oxygen content of the combustion air (air+FGR) will decrease, and the fuel supply will need to be reduced to maintain an appropriate air-fuel ratio. This leads to a decrease in the output of the burner. If most of the daily operation of the original burner is under * load, the output of the FGR may not be sufficient after modification, and FGR modification is not recommended at this time.
Technical Description of Low Nitrogen Burner
A low NOx burner refers to a burner with low NOx emissions during fuel combustion, and using a low Nx burner can reduce the emissions of nitrogen oxides during the combustion process.
Gas recirculation combustion technology
Gas recirculation technology is a technology that reduces nitrogen oxides by reintroducing some boiler exhaust into the furnace and mixing it with natural gas and air for combustion.
By using flue gas recirculation technology, the combustion temperature in the core area of the boiler is reduced, and the excess air coefficient remains unchanged. Without reducing the boiler efficiency, the generation of nitrogen oxides is suppressed, achieving the goal of reducing nitrogen oxide emissions.
10% -25% of the smoke exhaust from the boiler is returned to the front end of the boiler through the FGR smoke pipe from the boiler smoke exhaust main bow, and the smoke volume is adjusted through the regulating damper on the FGR smoke pipe; The combustion air enters the variable frequency fan after passing through the fresh air filter, and is boosted by the fan before reaching the front end of the boiler; The fuel gas passes through the double shut-off valve group and servo control valve before reaching the front end of the boiler; The smoke exhaust and combustion air from the boiler are mixed through a mixer and sprayed out with fuel gas through a specially designed nozzle, forming a stable flame in the boiler.
Diffusion combustion technology
This is a simple combustion method, which has the advantages of simplicity, easy ignition, no flashback, stable combustion, and simple fuel structure. The disadvantage is that for high calorific value gas with high air demand, complete combustion cannot be achieved through laminar diffusion, the CO content in the flue gas is relatively high, and the volume of the gas is not large. The forced blast diffusion combustion method is commonly used in industrial burners in industrial furnaces.