氢混天然气燃气轮机加湿低氮燃烧性能研究

为了解贫预混燃烧室天然气掺氢加湿燃烧时的性能变化和容许加湿范围，解决氢混燃气轮机NO_x排放超标问题，以某燃气轮机燃烧室为研究对象，数值研究了掺氢比和加湿比对燃烧性能及污染物排放特性的影响。结果表明：燃料无加湿条件下，燃烧室出口CO和CO₂排放值随着掺氢比的增加而减小，较高燃烧温度将导致热力型NO_x排放值增加，掺氢比达到0.2以上时，NO_x排放已超出环保限值；燃料加湿条件下，随着加湿程度增加，燃气出口平均流速及水蒸气组分含量均增加，燃烧筒内全局温度、CO₂和NO_x排放值均降低，CO排放值先降低后增加；掺氢天然气加湿可实现低氮燃烧，考虑到低掺氢工况燃气轮机功率输出效能和高掺氢工况燃烧性能恶化问题，水蒸气加湿量不宜过多，当掺氢比为0.3时，推荐燃料加湿比为0.463。

Research on DeNOx Combustion Performance of Humidified Natural Gas with H2 Blending in Gas Turbine

In order to understand the performance changes and allowable humidifying range of natural gas blended with hydrogen in a lean premixed combustor, and to solve the problem of NOx emissions exceeding the standard in hydrogen blended gas turbine, taking a gas turbine combustor as research object, the influence of blending hydrogen ratio and humidification ratio on its combustion performance and pollutant emissions characteristics was numerically studied. The results show that under the condition of no humidification of the fuel, the CO and CO2 emissions from the combustor outlet drop with the increase of hydrogen blending ratio. However, thermal NOx emissions will increase because of higher combustion temperature. When the hydrogen blending ratio reaches above 0.2, NOx emissions exceed the environmental protection limiting value; under fuel humidification conditions, the average gas outlet velocity and H2O mass fraction increase, and the global temperature decreases together with the emissions of CO2 and NOx in the combustor, whereas the CO emissions decrease first and then increase with the increment of humidification ratio; humidified natural gas with H2 blending can achieve deNOx combustion, but the amount of water vapor humidification ought to be moderate considering the following issues, such as the power output efficiency of gas turbine under low hydrogen blending ratio conditions and the deterioration of combustion performance under high hydrogen blending ratio conditions. The recommended fuel humidification ratio is 0.463 when the hydrogen blending ratio is 0.3.