How To Choose A Suitable Low Nox Burner?

A burner is a general term for a device that causes a mixture of fuel and air to be sprayed and burned in a proportional way. Low NOx burner is widely applied in the oil and refinery industry, it can obtain the best combustion parameters by adjusting the combustion air and the combustion head. Do you really know how to choose a suitable low NOx burner?

The correct selection of burners has an important impact on the safe and economic operation of the furnace. The furnace burners should be selected according to the structural characteristics, performance requirements and fuel characteristics of the furnace body, combined with the using conditions of the customer. For different fuels, unreasonable burners will cause safety not only accidents during use but also environmental pollution and energy waste.

Ruichang is a leading low NOx burner manufacturer of China, we are specialized in process burner, sulfur recovery unit, heat exchanger and FCC equipment. With rich experience in various projects of the oil refinery industry and petrochemical industry, we can provide you trusted products and full service, welcome to contact if you have any questions of burners selection.

The function of low NOx burner

• The fuel and the air required for combustion are sent to the furnace through a nozzle at a certain ratio, speed and mixing way.
• Guaranteed to burn quickly and fully.
• Fit well with load changes and changes in coal types during operation.
• Reduce NOx production and meet environmentally friendly ultra-low emission requirements.

The selection basis of low NOx burner

1. By the fuel. The user can choose furnace burner according to the fuel types and fuel properties such as pressure, component, calorific value, impurity, the content of the corrosive medium. Besides that, the installation group of furnace burners should be also suitable for the fuel property.
2. The shape and size of the burner’s flame should be matched with the combustor of the furnace. The combustion flame of a burner has a certain geometry and size and varies from burner to burner. When you select the burner, ensure the flame diameter and length are compatible with the furnace structure. It is necessary to ensure a good fullness, and the flame diffusion (diameter or range) cannot wash the heating surface. The dimension figure of burner flame is typically provided by low NOx burner manufacturers, to determine the length and size of the flame required by the user based on fuel consumption or burner power. Generally, the flame diameter should be less than the diameter of the combustion chamber, and the fullness is good. The flame length is less than the length of the combustion chamber and requires a margin of 50-100 mm. If the geometry of the burner flame is not accompanied by the combustion chamber, for example, if the combustion chamber is too small and the flame diameter and length are large, the combustion cannot sufficiently transfer the heat to the furnace, and the flame directly washes the heated surface, thereby making the unburned gas rapidly cooled and carbon is accumulated on the heated surface. If the combustion chamber is too large and the flame diameter is small, the flame fullness is poor and the furnace temperature is low. It can be seen that the geometry of the burner flame does not match the combustion chamber, which may cause energy waste and environmental pollution.
3. Depending on the temperature accuracy requirements of the equipment. You can choose one-stage fire control, two-stage fire control, progressive, proportional-regulated burner. Generally, the larger the adjustment range of the burner is, the better it can be, and it can better adapt to the change of load. If the adjustment of the selected burner cannot meet the requirements of load change, it will affect the accurate control of air temperature and air pressure, thus affecting furnace thermal efficiency. When the furnace loads change, the burner may be incompletely burned or unstable.
4. Ignition device matching conditions. The user selects the appropriate ignition device based on actual conditions.
5. Multiple burner arrangements (mutual configuration, fuel, air distribution system, ignition, flameout conditions, load regulation requirements). According to the fuel consumption and the power of the single burner, the number of burners is determined, and the fuel is distributed reasonably, the air distribution system is controlled, the ignition of each burner is controlled, the flameout condition is controlled, and the load regulation requirements of each burner are controlled.
6. Different regions and environments have various requirements for burners. At different altitudes, the atmospheric density is different. As the altitude increases, the air density decrease, which reduces the oxygen content in the air and the fan pressure, and then, affecting the matching of the burner output and the crossing.
7. Select flue gas emissions and noise levels that meet environmental standards, mainly include SO2, CO, and NOx emissions, they must be below the specified standards.
8. Choose a burner with simple structure, reliable operation, easy adjustment of control and repair, and easy to achieve automatic control of the combustion process. The simpler the structure, the higher the degree of automation, and the higher the safety factor.