The low-NOx fully premixed surface burner is an advanced combustion equipment. It has significant features and advantages. Firstly, it excels in NOx emission control and can effectively reduce the generation and emission of NOx, thus reducing pollution to the environment.
It works by pre-mixing the gas and air in precise proportions and then burning them on a special surface. This pre-mixing makes the combustion more adequate and even, and improves the combustion efficiency.
In addition, it has good stability and reliability and can adapt to different working conditions and load changes. It has a wide range of application prospects in the field of energy use and environmental protection.
With the increasing prominence of global environmental issues, reducing pollution and energy saving and emission reduction has become a key issue in the development of today's society. In this context, the ultra-low nitrogen burner, as a new type of energy-saving and environmental protection equipment, has become an important force to promote the upgrading of environmental protection industry.
Ultra-low nitrogen burner is a kind of combustion device specially used in industrial boilers, gas turbines, generator sets and other equipment. Traditional combustion equipment in the combustion process will produce a large number of nitrogen oxides, these substances not only cause serious pollution to the environment, but also a potential threat to human health. The ultra-low nitrogen burner through the optimisation of the combustion process and control of the combustion temperature, effectively reducing the generation of nitrogen oxides, to achieve the purpose of reducing pollution emissions.
The application of ultra-low nitrogen burners has significant energy saving and emission reduction effects. Firstly, by optimising the combustion process and improving the combustion efficiency, the fuel consumption can be reduced, so as to achieve the goal of energy saving. Secondly, by reducing the emission of nitrogen oxides, the concentration of air pollutants can be reduced, air quality can be improved, and the ecological environment can be protected. In addition, the ultra-low nitrogen burner has the characteristics of stable combustion, low noise, low vibration, etc., which can improve the operating efficiency and service life of the equipment.
The application of ultra-low nitrogen burners has been widely promoted and applied. In the industrial field, many large enterprises have adopted ultra-low-nitrogen burners to replace old combustion equipment, improve environmental protection awareness and energy saving and emission reduction. In the field of power generation, ultra-low nitrogen burners can be combined with generator sets to achieve green power generation and reduce pollution emissions. In the field of construction, ultra-low nitrogen burners can be applied to HVAC systems, hot water supply systems, etc. to improve energy efficiency and reduce energy waste.
The application of ultra-low nitrogen burners is not only conducive to environmental protection, but also of great significance in promoting the upgrading of environmental protection industry. Firstly, the development and production of ultra-low-nitrogen burners require a large number of scientific research and technical personnel, which promotes scientific and technological innovation and personnel training. Secondly, the promotion and application of ultra-low-nitrogen burners can lead to the development of the related industrial chain, which promotes the progress of combustion equipment manufacturing and environmental protection technology. In addition, the export of ultra-low-nitrogen burners can also expand foreign trade and enhance the comprehensive competitiveness of the country.
In conclusion, as a new type of energy-saving and environmental protection equipment, the ultra-low nitrogen burner has important social significance and economic value. It can not only effectively reduce pollution emissions and save energy, but also promote the upgrading of environmental protection industry and sustainable economic development. In the future, we should further increase the research and development and application of ultra-low-nitrogen burners to promote the further deepening of environmental protection and create a better future for mankind.
Burner is one of the key equipments of the tube heating furnace, its good or bad is directly related to the thermal efficiency of the heating furnace and the process, therefore, the burner puts forward the following requirements:
(1) Adapt to the needs of different furnace types, to ensure that the furnace must be the heat intensity.
(2) to maintain a continuous and stable combustion, it should have a certain shape, a certain length, smooth and unextinguished flame. The colour of the flame is orange, and its possibility of tempering and deflagration is small.
(3) The excess air coefficient is small, the combustion is complete, and the fuel gas mixes completely and evenly with the air.
(4) For liquid burner, it can make all kinds of fuel oil atomise evenly within the range of requirement adjustment.
(5) To meet the process requirements, operating flexibility, good regulation performance, simple and reliable operation, no noise at work.
(6) No blockage, no oil leakage, no coking.
(7) Simple and compact structure, small volume, light weight.
(8) Small operating costs, easy maintenance and replacement.
Tube heating furnace is supplied with heat by the burner firing, and then the heat is transferred to the oil through the stove pipe, so the interrelationship between the flame and the stove pipe becomes the main problem of the heating furnace. The burner is the equipment that supplies heat and consumes energy. Burner design, selection, manufacture and operation of good and bad directly related to the heating furnace thermal efficiency and the length of the operating cycle. If you leave the burner to talk about the good and bad of a heating furnace is not comprehensive, but also unrealistic.
Burner in the ignition often encountered point can not be the case, the reason is more, the following talk about the main reasons and ways to deal with:
(1) burner damper opening is too large or chimney baffle opening is too large, resulting in too much air into the furnace, in this case, the burner is not easy to light. The way to deal with it is: the burner damper opening and chimney baffle opening to adjust the small, to be lit, and then adjust the damper and baffle to the appropriate opening.
(2) When the fuel oil pressure is greater than the pressure of atomised steam, the burner is not easy to light. The treatment is: the fuel oil pressure to the atomised steam pressure than the small 98kPa or so.
(3) The pressure or temperature of fuel oil is too low, should contact with the relevant units to improve the pressure or temperature of fuel oil.
(4) The pressure or temperature of high-pressure gas is too low, should contact with the relevant unit to raise the pressure or temperature of gas.
(5) Fuel oil contains too much water, contact with the relevant unit for timely dehydration.
(6) High-pressure gas contains too much oil and water, contact with the relevant units for timely de-oil and dewatering.
(7) The amount of steam is too large and the amount of fuel oil is too small, the steam valve should be closed and the fuel oil valve should be opened appropriately in order to achieve a suitable oil-vapour ratio.
First, the impact of air preheating temperature
At present, in order to improve the combustion efficiency of the heating furnace and reduce the heat required to heat the cold air in the furnace, most burner equipment requires air preheating. Although air preheating improves the efficiency of the heating furnace, for some fuels also help ignition, but improves the flame temperature, for the control of NO. emissions have no positive effect.
Relevant studies have shown that NOx emission concentrations increase with increasing air preheating temperature. When the air is preheated, it is equivalent to reducing the cold air preheating energy consumption under the same power output conditions, thus increasing the premixed flame temperature, and therefore the NOx emission concentration is increased. If complete premixed combustion is used, then the overall NOx emission concentration is low.
Second, the influence of fuel and air premixing degree
At present, most of the large burners are used in non-premixed combustion, that is, gas and air in the burner is not mixed, but in the burner outlet through different jets, whirlpools, etc., so that the two streams of air mixed with each other and ignition combustion occurs. This combustion rate depends on the mixing rate of air and gas, called diffusion-controlled combustion. For gas and air mixed in advance in the burner and then ignited at the exit of the combustion method called premixed combustion. The combustion rate of premixed combustion depends on the kinetic reaction rate of the fuel itself and is therefore called kinetic controlled combustion. Both types of combustion have different advantages and disadvantages, and the varying degree of premixing of the fuel and air also has a significant effect on NOx production.
As the premixing degree increases, the concentration of fast type NOx decreases and the concentration of thermal type NOx increases. Therefore, it can be assumed that in the range of 30%~70% premixing degree, the fast NOx generation and thermal NOx generation work together, and the NOx generation does not change much in this range because of the relationship between the two with the change of premixing degree, but when the premixing degree is more than 70%, the conditions of the fast NOx generation are weakened, and the thermal NOx generation starts to dominate. dominate.
Third, the influence of gas/air velocity ratio
In a non-premixed burner, the gas and air are separately ejected from the nozzle and then mixed in a certain way. Therefore, the gas and air velocity ratio has a great influence on the mixing effect and affects the rate of combustion reaction. As the gas/air injection velocity ratio increases, the peak flame temperature rises slightly, but the temperature distribution in the furnace tends to be uniform, and NOx emissions are reduced.
Fourth, the impact of flue gas recirculation rate
Flue gas recirculation is in the heating furnace before the air preheater to extract a portion of the low-temperature flue gas directly into the furnace, or with the primary or secondary air mixed into the furnace, which not only reduces the combustion temperature, but also reduces the concentration of oxygen, which reduces the concentration of NOx emissions. From the air preheater before the extraction of lower temperature flue gas, through the recirculation fan will be extracted flue gas into the air flue gas mixer, and air mixed together into the furnace, the recirculation of flue gas volume to the amount of flue gas without the use of flue gas recirculation is called the flue gas recirculation rate.
Experience shows that when the flue gas recirculation rate is 15-20%, the NOx emission concentration of pulverised coal furnace can be reduced by about 25%.The reduction rate of NOx increases with the increase of the flue gas recirculation rate and is related to the type of fuel and the combustion temperature.The higher the combustion temperature is, the higher the influence of the flue gas recirculation rate on the NOx reduction rate.
