最近几年对人们生活影响极大的雾霾、臭氧污染和酸雨都和氮氧化物（NOx）息息相关。氮氧化物（NOx）对环境的损害作用极大，氮氧化物与空气中的水结合最终会转化成硝酸和硝酸盐，硝酸是酸雨的原因之一；它与其它污染物在一定条件下能产生光化学烟雾污染。

随着锅炉机组朝着大容量高参数方向发展，实现高效燃烧，减少污染物排放，提升煤种适应性，提升运行安全性和可靠性是现代燃烧技术追求的目标。这其中，有效降低氮氧化物排放量更是摆在了首位。 

In recent years, haze, ozone pollution and acid rain that affect people's lives are closely related to nitrogen oxides (NOx). Nitrogen oxides (NOx) have great damage to the environment. The combination of nitrogen oxides and water in the air will eventually convert into nitric acid and nitrate. Nitric acid is one of the reasons for acid rain; it can produce photochemical smog under certain conditions.

With the development of large capacity and high parameters in the direction of boiler units, it is the goal of modern combustion technology to achieve high efficiency combustion, reduce pollutant emission, improve the adaptability of coal and improve the safety and reliability of operation. Among them, the effective reduction of NOx emissions is the first place.

低氮燃烧器选择考虑的主要参数

1. NOx 排放

必须满足国家和地方的环保排放要求，在满足要求的前提下，从企业的社会责任角度出发，尽量应该选择NOx排放更低的设备；

2. 尾氧含量

为了达到充分燃烧的极限过剩空气系数为大约1.1, 对应的理论尾氧含量为大约2%. 更高的尾氧含量通常意味着燃烧器效率的降低。理想的燃烧器最好尾氧含量可以控制在3%以内；市场上表面燃烧的燃烧器的尾氧含量通常在7%左右，相对于3%的尾氧含量，意味着产生相同的热量，需要多耗费大约6~8%的天然气。对于常年运转或者设备长期在较高负荷运转，天然气消耗量比较大的业主，选择一款尾氧含量低的燃烧器对于降低运行成本至关重要。

3. 可调比

采用了电子比例调节的低氮燃烧器通常应该具备至少５：１以上的高可调比。更低的可调比意味着实际运行过程中更多的ON/Off启停，同时也意味着更多的天然气消耗。除非是负荷常年在一个比较小的稳定区间的锅炉，选择一个高可调比的燃烧器对于降低天然气的消耗，降低运行成本，延长设备的使用寿命非常重要。

4. 其它主要考虑因素

燃烧稳定性是选择低氮燃烧器的主要考虑因素，包括设备本身的可靠性。由于在北京实施低氮标准之前，全世界范围内实施低氮标准的区域主要在美国，所以基本上只有主要销售市场在美国的燃烧器品牌在低氮燃烧器领域具有比较长的应用经验。

Main parameters of low nitrogen burner selection

1. NOx emission

It is necessary to meet the national and local environmental emission requirements. On the premise of meeting the requirements, from the point of view of the social responsibility of the enterprise, we should choose the lower NOx emission equipment as far as possible.

2. tail oxygen content

To achieve full combustion limit excess air coefficient is about 1.1, the corresponding theoretical tail oxygen content is about 2%. higher tail oxygen content usually means reducing the burner efficiency. The best tail oxygen content of the ideal burner can be controlled within 3%; the tail oxygen content of the combustor on the market is usually about 7%, compared with the 3% tail oxygen content, which means that the same amount of heat is produced and the natural gas of about 6~8% is needed. For the owners who run for a long time or the equipment is running at a high load for a long time and the gas consumption is large, it is very important to choose a burner with low tail oxygen content to reduce the operating cost.

3. adjustable ratio

The low nitrogen burner with electronic proportional adjustment should normally have a high adjustable ratio of at least 5:1. The lower adjustable ratio means more ON/Off startup and shutdown in actual operation, and at the same time it means more natural gas consumption. It is very important to choose a high adjustable burner for reducing the consumption of natural gas, reducing the operating cost and prolonging the service life of the equipment, unless it is a boiler in a relatively small stable interval.

4. other major considerations

Combustion stability is the main consideration for choosing low nitrogen burner, including the reliability of the equipment itself. Before the implementation of the low nitrogen standard in Beijing, the world wide range of low nitrogen standards is mainly in the United States, so basically only the major sales markets in the United States have a long experience in the field of low nitrogen burner in the field of burner.