Utilization of domestic waste biomass char in the context of carbon neutrality—low NO_x decoupled combustion

The carbon and nitrogen content of township waste is high, and direct combustion causes a large amount of CO₂ and NO_x emissions. The biomass carbon after pyrolysis can reduce the NO in the combustion flue gas to N₂, which can reduce NO_x emissions while using carbon resources. Using 6 typical components in 4 kinds of rural solid waste (including paper, plastic, wood and textile) as experimental materials, the pyrolysis and decoupling combustion experiments are carried out in a fixed-bed reactor to investigate the effect of decoupling combustion on NO_x emission. The experimental results showed that when the pyrolysis temperature was 700 ℃ and the particle size were 1.6–2.5 mm, the concentration of reducing gas in pyrolysis gas was higher and the reduction rate of NO in the char reached over 60%. By comparing the N conversion of decoupling combustion with that of normal combustion and air staged combustion, the NO_x emission reduction rates of the decoupling combustion were 44.1% and 18.1%, respectively. Therefore, the decoupling combustion of rural solid waste based on pyrolysis is an effective way to control NO_x emission, which is conducive to the clean and efficient transformation and utilization of rural solid waste.