空气分级燃烧等低NOx燃烧技术广泛应用于电厂锅炉，以降低炉膛出口NOx浓度，但实际应用过程中会造成锅炉水冷壁腐蚀，严重影响煤粉锅炉的安全运行。为了准确预测锅炉水冷壁附近H2S浓度，运用Chemkin软件对已建立的H2S生成详细反应机理模型进行评估并简化。验证C/H/O详细反应机理与H2S生成详细反应机理的耦合性，表明GRI-3.0能更好地预测煤粉富燃料燃烧过程中重要组分浓度分布；将耦合后的机理作为起始机理，与其他学者建立的硫详细反应机理进行比较，结果表明，本课题组的硫组分详细反应机理模型能够较好地描述煤粉燃烧过程中气态硫组分的演化，将CS2作为重要硫组分进行研究，能够更好地预测硫组分浓度分布；通过简化结果比较，选择基于误差传递的直接关系图法(DRGEP)的简化结果作为硫组分简化反应机理，包含15个组分和28个基元反应，并在1 373～1 673 K验证，表明该简化机理适用于煤粉富燃料燃烧过程中硫组分浓度分布预测。

Various low-NOx combustion technologies,such as air-staged,are currently widely used in coal-fired boilers to reduce NOx concentration at furnace outlet. However,in practical application,these technologies cause sulfidation corrosion of the boiler water-wall,and affect the safe operation of pulverized coal boiler. In order to accurately predict the concentration of H2S near the boiler water wall,the gas-phase kinetics software Chemkin software was used to evaluate and simplify the established detailed reaction mechanism model of H2S generation. First,in this paper,the coupling between the detailed reaction mechanism model of sulfur species and the detailed reaction mechanism of C/H/O was verified,which showed that GRI-3.0 could better predict the concentration distribution of important components in pulverized coal-fired boiler with air-staged. Then,the coupling mechanism model was taken as the initial mechanism and compared with other detailed sulfur reaction mechanisms. The results show that the detailed reaction mechanism model of sulfur species in our research group can better describe the evolution of gaseous sulfur species during pulverized coal combustion,and CS2 is considered as an important sulfur species to better predict the concentration distribution of sulfur species. Finally,by comparing the simplified results,the result obtained by the directed relation graph with error propagation(DRGEP)is selected as the simplified reaction mechanism model of the sulfur species,including 15 species and 28 reactions,which has been verifying in the temperature range of 1 373-1 673 K. The results show that reduced mechanism model can be applied to the prediction of the sulfur species concentration distribution during the fuel-rich combustion of pulverized coal.

0 引言

1 研究方法

   1.1 C/H/O详细反应机理

   1.2 PFR模型描述和试验设置

   1.3 误差评估

   1.4 机理简化方法

2 详细机理验证及评估

   2.1 反应器参数设置

   2.2 详细机理验证

   2.3 详细机理评估

3 机理简化及验证

4 结论