Numerical Study on NOx Emissions of Methane Re-Combustion in a 600 MWe Coal-Fired Boiler

• 作者: Aijun Wang Chengyu Zhang Foyuan Duan Haoliang Mu Hussain Ahmad Madni Gondal Weidong Zhang Xiaotao Zhang
• 来源期刊: 能源与动力工程(英文)
• 学科: 工学
• 关键词: NUMERICAL Simulation Re-Combustion NOx EMISSION Reduction
• 年，卷（期）: 2020,（3）
• 页码范围: 101-107
• 页数: 7页
• 分类号: TK1

摘要

The fuel staging combustion technology is a promising low NOx combustion technology for coal-fired boiler. In order to reduce NOx emissions, the burners of a 600?MWe coal-fired boiler are retrofitted in which methane gas is selected as a secondary fuel for re-combustion. The CFD models of combustion process are built to investigate?effects of the methane gasratio on combustion process and NOx emissions. A total of 4 cases are numerically studied, including the pure coal combustion case, the coal combustion with 7.5%, 10%, 12.5% of methane gas re-combustion cases respectively. The results show that the re-combustion of methane can reduce the temperature at primary combustion zone, but increase the temperatures at the re-combustion area and the furnace outlet. The NOx concentration at the furnace outlet reduces with the increasing methane gas ratio.?Methane re-combustion can greatly benefit to the NOx emissions reduction.