To address the issues of flashback and high NO_x emissions in hydrogen-enriched gas combustion

a swirl-stabilized burner was designed using mild premixed combustion technology

and a feasibility study was conducted for its application in industrial boilers. Using a combination of experimental and numerical simulation methods

the study explored the equivalence ratio adjustment range of the mild premixed burner and the influence of hydrogen blending ratio on flame shape and pollutant emission characteristics. The experimental results showed that the mild premixed burner can achieve a wide hydrogen blending heat ratio adjustment range of 0～100%. The addition of hydrogen promoted a more uniform flame distribution

and the flame height decreased with the increasing hydrogen blending ratio. Additionally

the NO_x mass concentration experienced a rapid increase(for hydrogen blending ratios less than 30%) followed by fluctuations around 60 mg/m~3. As the hydrogen blending ratio increased

the critical equivalence ratio for local flashback decreased

narrowing the stable combustion range between the blowout limit and the partial flashback limit. The widest equivalence ratio stable combustion range was achieved at a hydrogen blending ratio of 40%

which was 0.54～1.06.