Nitrogen oxides (NO_x) from combustion contribute significantly to atmospheric pollution. An experimental setup was employed to investigate the application of three primary denitrification methods, i.e., reburning (staged combustion), overfiring air (OFA), and flue-gas recirculation (FGR), individually and in combination, combusting natural gas (NG) and propane–butane gas (PBG). Fuel heat inputs of 16 and 18 kW and air excess coefficients of 1.1 and 1.2, respectively, were tested. The highest individual denitrification efficiency of up to 74% was obtained for FGR, followed by reburning and OFA. A denitrification efficiency between 8.9% (reburning + OFA) and 72% (reburning + OFA + FGR) with NG combustion was observed. Using a 20% FGR rate yielded denitrification efficiency of 74% for NG and 65% for PBG and also led to a significant decrease in carbon monoxide (CO) emissions, so this can be recommended as the most efficient denitrification and de-CO method in small-scale furnaces. Reburning alone led to a sharp, more than 12-fold increase in CO emissions compared to the amount without any other method application. The presented results and the difference between our experimental data and the literature data acquired in some other studies indicate the need for further research.

中文翻译：

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主要脱硝方法应用对小型炉NOx和CO排放影响的实验研究

氮氧化物（NO _x燃烧造成的）大大污染了大气。实验装置用于研究三种主要脱硝方法的应用，即再燃烧（分步燃烧），过度燃烧空气（OFA）和烟气再循环（FGR），分别或组合使用，燃烧天然气（NG）和丙烷-丁烷气（PBG）。分别测试了16和18 kW的燃料热输入以及1.1和1.2的空气过剩系数。FGR，再燃和OFA的最​​高个人反硝化效率高达74％。观察到，NG燃烧的反硝化效率在8.9％（再燃+ OFA）和72％（再燃+ OFA + FGR）之间。使用20％FGR率时，NG的反硝化效率为74％，PBG的反硝化效率为65％，并且还导致一氧化碳（CO）排放量显着减少，因此可以推荐将其作为最有效的反硝化和CO脱氮方法。小型熔炉。与不使用任何其他方法的排放量相比，仅进行再燃烧即可导致CO排放量急剧增加（超过12倍）。提出的结果以及我们的实验数据与其他一些研究中获得的文献数据之间的差异表明需要进一步研究。