低氮燃烧器如何选择?
如何选择低氮燃烧器?令许多厂家有些时候不知所措。下面小编从低氮燃烧器的类型、选择低氮燃烧器考虑的因素,来给大家解答低氮燃烧器如何选择?
How to choose a low nitrogen burner?
How to choose a low nitrogen burner? Many manufacturers are sometimes at a loss. Below small small make up from the type of low nitrogen burner, choose the factor that low nitrogen burner considers, answer to everybody how low nitrogen burner chooses?
一、低氮燃烧器的类型
Type of low nitrogen burner
燃烧器是工业燃油锅炉、燃气锅炉上面的的重要设备,它保证燃料稳定着火燃烧和燃料的完全燃烧等过程,因此,要抑制NOx的生成量就必须从燃烧器入手。根据降低NOx的燃烧技术,低氮氧化物燃烧器大致分为以下几类:
Burner is an important equipment in industrial fuel boiler and gas boiler, which ensures the stable ignition of fuel and the complete combustion of fuel. Therefore, to suppress the production of NOx, it must start with burner. According to the combustion technology of reducing NOx, low-nitrogen oxide burners are generally divided into the following categories:
1.低NOx预燃室燃烧器
1. Low NOx precombustion chamber burner
预燃室是近10年来我国开发研究的一种高效率、低NOx分级燃烧技术,预燃室一般由一次风(或二次风)和燃料喷射系统等组成,燃料和一次风快速混合,在预燃室内一次燃烧区形成富燃料混合物,由于缺氧,只是部分燃料进行燃烧,燃料在贫氧和火焰温度较低的一次火焰区内析出挥发分,因此减少了NOx的生成。
Precombustion chamber development research in China in recent 10 years is a kind of high efficiency and grade of low NOx combustion technology, generally speaking, a precombustion chamber of the wind or secondary air and fuel injection system, etc, the mixed fuel and a wind, in a form in the combustion zone precombustion indoor fuel mixture, due to the lack of oxygen, is only part of the fuel combustion, fuel in poor oxygen and low flame temperature of a flame volatile precipitation in the area, thereby reducing NOx formation.
2.阶段燃烧器
2. Stage burner
根据分级燃烧原理设计的阶段燃烧器,使燃料与空气分段混合燃烧,由于燃烧偏离理论当量比,故可降低NOx的生成。
The phase burner designed according to the principle of graded combustion makes the fuel and air burn in different stages. As the combustion deviates from the theoretical equivalence ratio, the generation of NOx can be reduced.
3.自身再循环燃烧器
3. Self recirculation burner
一种是利用助燃空气的压头,把部分燃烧烟气吸回,进入燃烧器,与空气混合燃烧。由于烟气再循环,燃烧烟气的热容量大,燃烧温度降低,NOx减少。
One is to use the pressure head of combustion-supporting air to absorb part of the burning smoke back into the burner and burn it with the air. Due to the recirculation of flue gas, the heat capacity of flue gas is large, the combustion temperature is reduced, and NOx is decreased.
另一种自身再循环燃烧器是把部分烟气直接在燃烧器内进入再循环,并加入燃烧过程,此种燃烧器有抑制氧化氮和节能双重效果。
Another kind of self-recirculation burner is to put part of the flue gas into the recirculation directly in the burner and add the combustion process. This kind of burner has the dual effect of inhibiting nitrogen oxide and saving energy.
4.浓淡型燃烧器
4. Thick and light type burner
其原理是使一部分燃料作过浓燃烧,另一部分燃料作过淡燃烧,但整体上空气量保持不变。由于两部分都在偏离化学当量比下燃烧,因而NOx都很低,这种燃烧又称为偏离燃烧或非化学当量燃烧。
The idea is that some of the fuel is burned too much, and some of the fuel is burned too little, but the total amount of air over the air remains the same. Since both parts are burning away from the chemical equivalence ratio, the NOx is very low, which is also called deviation combustion or non-chemical equivalent combustion.
5.分割火焰型燃烧器
5. Split flame burner
其原理是把一个火焰分成数个小火焰,由于小火焰散热面积大,火焰温度较低,使"热反应NO"有所下降。此外,火焰小缩短了氧、氮等气体在火焰中的停留时间,对"热反应NO"和"燃料NO"都有明显的抑制作用。
The principle is to divide a flame into several small flames. As the small flame has a large heat dissipation area and a low flame temperature, the "heat reaction NO" decreases. In addition, the small flame shortens the residence time of oxygen, nitrogen and other gases in the flame, and has obvious inhibition effect on both "heat reaction NO" and" fuel NO".
6.混合促进型燃烧器
6. Mixed accelerator burner
烟气在高温区停留时间是影响NOx生成量的主要因素之一,改善燃烧与空气的混合,能够使火焰面的厚度减薄,在燃烧负荷不变的情况下,烟气在火焰面即高温区内停留时间缩短,因而使NOx的生成量降低。混合促进型燃烧器就是按照这种原理设计的。
The residence time of flue gas in the high temperature area is one of the main factors influencing NOx production. Improving the mixture of combustion and air can reduce the thickness of the flame surface. The mixed - boost burner is designed according to this principle.
二、
低氮燃烧器选择考虑的主要参数
2. Main parameters considered in the selection of low nitrogen burner
1、可调比
1. Adjustable ratio
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。
Low nitrogen burners with electronic proportional regulation should usually have a high adjustable ratio of at least 5 to 1. A lower tunable ratio means more ON/Off stops during the actual operation and more gas consumption. Unless it is a boiler loaded in a relatively small stable range all year round, it is important to select a high adjustable ratio burner to reduce gas consumption, reduce operating costs, and extend the service life of the equipment.
2、NOx排放
2. NOx emission
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;
It is necessary to meet the requirements of national and local environmental protection emissions. On the premise of meeting the requirements, from the perspective of corporate social responsibility, the equipment with lower NOx emissions should be selected as far as possible.
3、尾氧含量
3. Tail oxygen content
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。
In order to reach the maximum excess air coefficient of full combustion, which is about 1.1, the theoretical tail oxygen content is about 2%. A higher tail oxygen content usually means a reduction in burner efficiency. The optimal tail oxygen content of the ideal burner can be controlled within 3%. The tail-oxygen content of combustion burners on the market's surface is usually around 7%, which means the same amount of heat is produced, compared with 3% of tail-oxygen content, which requires about 6-8% more natural gas to be consumed. For the owners who operate all year round or whose equipment is under high load for a long time and whose natural gas consumption is relatively high, it is very important to select a burner with low tail oxygen content to reduce the operating cost.
4、其它主要考虑因素
4. Other major considerations
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。从燃烧稳定性的角度考虑,对于采用FGR技术的低氮燃烧器,需要特别关注FGR烟气再循环比例,过大的比例意味着燃烧极易不稳定,或者对于设备的技术和控制水平有比较苛刻的要求。
Combustion stability is the main consideration for selecting low nitrogen burners, including the reliability of the equipment itself. From the perspective of combustion stability, for low nitrogen burners using FGR technology, special attention should be paid to the ratio of flue gas recirculation of FGR. Too large a proportion means that the combustion is easy to be unstable, or there are strict requirements on the technology and control level of the equipment.
如果想了解更多关于低氮燃烧器相关知识,请咨询北京云顶国际节能环保技术有限公司。
For more information on low nitrogen burners, please consult Beijing chuangwei electromechanical equipment co., LTD.