Pressurized Oxy-combustion is one of the most promising technologies for carbon capture, utilization, and storage (CCUS) of coal utilization. In pressurized oxy-combustion, the removal of acid gas pollutants and the latent heat of moisture condensation are mainly carried out by an integrated direct-contact wash column (DCC). Recent studies have shown that the inlet concentration of NO_x in the column is important for the combined removal of NO_x and SO_x, therefore, it is essential to control the NO_x emissions before the DCC. Selective non-catalytic reduction (SNCR) is a promising and economical technology of NO_x reduction; however, no study has been conducted on SNCR at elevated pressure, especially in pressurized oxy-combustion. In this paper, kinetic modeling is carried out to explore and optimize the NO_x reduction by SNCR in pressurized oxy-combustion. First, the detailed mechanism used in this study is validated by the experimental results in literature. Based on the validation of the detailed mechanism, the effects of different parameters including temperature, oxygen concentration, moisture content, NH₃ concentration, and SO₂ concentrations on the SNCR performance are analyzed at higher pressures in oxy-combustion atmosphere. The modeling results show that by increasing the pressure from 1 atm to 15 atm, the SNCR de-NOx efficiency increased by 2–3%. The width of the optimum temperature window for maximum De-NO_x is broadened from 1250K to 1450K with increasing the pressure from 1 atm to 10 atm. The increase of pressure has no significant effect on thermal de-NOx efficiency with increasing the NH₃/NO ratio. At higher pressure (10 atm) the increase in O₂ concentration from 1 to 20% the de-NOx efficiency decreases almost twice as much as at 1 atm. The increase of SO₂ and moisture contents at high pressure have no significant effect on the de-NOx efficiency. Rate of production (ROP) and sensitivity analysis are performed to determine the dominant reaction paths of de-NO_x in pressurized-oxy SNCR process. This study can provide guidance for the process optimization of de-NO_x by SNCR in pressurized oxy-combustion.

加压氧燃烧是用于煤炭利用的碳捕获，利用和储存（CCUS）的最有前途的技术之一。在加压氧燃烧中，酸性气体污染物的去除和湿气冷凝潜热主要由集成的直接接触式洗涤塔（DCC）进行。最近的研究已经表明，NO的入口浓度_X在列是该组合的去除NO的重要_X和SO _X，因此，它以控制NO是必不可少的_X的DCC之前排放。选择性非催化还原（SNCR）是NO的有希望的和经济的技术_X减少; 但是，尚无关于在高压下进行SNCR的研究，特别是在加压氧燃烧方面。在本文中，动力学模型进行探索和优化NO _X通过SNCR在加压氧燃烧降低。首先，文献中的实验结果验证了本研究中使用的详细机理。在详细机理验证的基础上，温度，氧气浓度，水分含量，NH ₃浓度和SO ₂等不同参数的影响在氧气燃烧气氛中，在较高压力下分析SNCR性能上的浓度。模拟结果表明，通过将压力从1个大气压增加到15个大气压，SNCR的NOx去除效率提高了2-3％。的最佳温度窗口最大脱NO的宽度_X是从1250K扩大到1450K与从1个大气压增加压力大气压〜10个。随着NH ₃ / NO比的增加，压力的增加对热脱硝效率没有明显影响。在较高的压力（10个大气压）下，O ₂浓度从1％增加到20％，脱硝效率下降几乎是1个大气压时的两倍。SO ₂的增加高压下的水分含量对脱硝效率没有显着影响。进行生产率（ROP）和灵敏度分析，以确定在加压氧SNCR过程中脱硝_x的主要反应路径。这项研究可以提供的流程优化指导去NO _X在加压氧燃烧通过SNCR。