Low NOx Transformation Method Of Natural Gas Boiler Burner
Low NOx Transformation Method Of Natural Gas Boiler Burner
The natural gas boiler is the most widely used boiler product after the coal-fired boiler, and it is also the mainstream product at present. Gas is the natural gas, liquefied gas, gas, and biogas in the combustion process. The natural gas boiler is widely used, so people call them natural gas boiler. According to the new environmental protection law, the air pollution equipment shall be supervised, the pollutant discharge shall be strictly limited, the blue water and blue sky project shall be implemented, and the use of biomass briquette or natural gas is recommended. Governments at all levels will take corresponding measures to implement the plan of transforming coal-fired boilers into gas-fired boilers. Natural gas is a kind of clean fuel. It burns well and produces less ash, sulfur, and nitrogen than coal. At the same time, pipeline transportation of gas fuel can greatly reduce labor intensity, improve labor conditions and reduce operating costs. The implementation of the national “west to East Gas Transmission” and other projects has provided high-quality, sufficient, and cheap gas sources for the transformation of coal-fired boilers into gas-fired boiler burners.
The content of nitrogen oxides in the exhaust gas of gas-fired boilers is more than 150 mg per cubic meter, while the standard is less than 80 mg or less than 30 mg. The low NOx 80mg is called low NOx gas boiler, and the low NOx 30mg is called ultra-low nitrogen gas boiler.
How to carry out low NOx transformation for ordinary gas boilers?
First: The main body is changed to the boiler main body, that is, the boiler main body. By reforming the furnace and heating area, we can make the combustion of the gas-fired boiler more full, further reduce the nitrogen oxide content in the flue gas, and finally achieve the goal of low nitrogen gas transformation.
Second: The method of low nitrogen transformation of gas-fired boilers is generally based on burner transformation. The low NOx burner is replaced to make its performance more energy-saving, environmentally friendly, and efficient, thus reducing the nitrogen oxide content in the boiler tail gas. It is generally divided into low nitrogen burner and ultra-low nitrogen burner. The transformation methods of low nitrogen burner of gas boiler include:
1. The pressure head of combustion supporting air is used to suck back part of the flue gas after combustion, enter the burner, and mix with the air for combustion to form flue gas recirculation. Due to the recirculation of flue gas, the heat capacity of combustion flue gas is large, the combustion temperature is reduced, and the nitrogen oxide content is reduced. Another self-recycling burner is directly entering part of the flue gas into the burner and adding it to the combustion process. This burner has the dual functions of environmental protection and energy saving.
2. Full premixed burner (surface combustion) the full premixed combustion technology is to fully premix the combustion gas and air before entering the combustion chamber, so as to make the combustion more complete, improve the combustion efficiency, reduce the emission of harmful gases, and reduce the space demand of the combustion chamber. It is the first gas combustion technology in the world at present.
The low-nitrogen transformation of gas-fired boilers is mainly in the above two ways. The low-nitrogen transformation of burners is commonly used, which is generally applicable to small-scale gas boilers. The low-nitrogen transformation of large-scale gas boilers requires the furnace and burner to be carried out at the same time. The boiler body and burner are matched and can work efficiently.