Study on low nitrogen emission mode of combustion supporting air humidification gas-fired boilers

Zhang Qunli, Gao Wei, Niu Yu, Xiao Xin, Shen Qi and Sun Donghan

2020.09.16

Puts forward a low nitrogen emission mode of combustion supporting air humidification gas-fired boiler and two different operation modes of heat supply network utilizing waste heat and strengthening nitrogen reduction. Sets up a system experimental platform, and studies the influence of liquid gas ratio, moisture content of combustion supporting air and operation mode on nitrogen reduction effect of gas-fired boiler. The results show that increasing the moisture content of combustion supporting air has a significant effect on reducing NOx concentration of gas-fired boiler. The two operation modes can significantly reduce the NOx emission concentration, even lower than the latest limit value of gas-fired boiler emission standard. Compared with the operation mode of heat supply network utilizing waste heat, the effect of strengthening nitrogen reduction operation mode is more obvious, reaching 23.1 mg/m3, which can get a higher subsidy for low nitrogen retrofit. The operation mode of heat supply network utilizing waste heat can not only make the existing gas-fired boiler meet the NOx emission standard, but also have higher boiler thermal efficiency and better comprehensive benefits of energy conservation and environmental protection.