How To Choose Burners For Gas Boiler Reconstruction?
How To Choose Burners For Gas Boiler Reconstruction?
In recent years, with the concern of environmental pollution, coal-fired steam boilers are gradually replaced by natural gas and natural gas boilers. With the expansion of the sales market of natural materials and natural gas boilers, everyone’s focus has also been turned to understanding natural materials and natural gas boilers. How to choose natural gas boiler burner as the core component?
The emission index of the boiler, especially the NOx emission concentration, is closely related to the coal type, boiler type selection, and burner type. For the boilers in operation, the furnace type has been determined. However, in recent years, in order to increase the profitability of the coal-fired power plant and cope with the changeable electricity coal market, most of the coal used by the boiler is mixed and inferior to the original design coal. Therefore, First of all, it is necessary to fully evaluate the existing main coal types and common coal types of the boiler. In the feasibility demonstration of the transformation, there are many cases where the NOx emission reduction effect after the transformation is not obvious and new problems are caused due to improper selection of coal types. Secondly, it is necessary to conduct a bottom-up test on the boiler in operation to fully evaluate the combustion performance, steam parameters, heating surface wall temperature, coking and slagging, operation adjustment, thermal automation, and other problems existing in the operation of the boiler, Put forward the expected objective of scientific and reasonable transformation, weigh the economic index and environmental protection index of the boiler, and effectively improve the existing problems through transformation. Because of the diversity and originality of the gasoline diesel gas heating furnace. Many people do not understand the difficult problem of matching the gasoline and diesel gas heating furnace and burner. The selection becomes small, and the gasoline and diesel gas heating furnace cannot give full play to all normal professional abilities; Large selection will lead to consumption of gasoline, diesel, and natural gas. Then how do select the suitable natural gas burner according to the output power of the heating furnace and its own specific conditions?
1. The burner selected by the manufacturer is mainly an imported or domestic burner. The main characteristics of imported burners are perfect technology, a high level of fine management, high-efficiency environmental protection, and high-cost performance (high safety factor, stable system software), but at the same time, the price is high. China’s natural gas burner system software is immature, with poor reliability and low thermal efficiency, but the price is cheap. Nowadays, the key brands of imported burners include Italy EBICO burner, Spain riyals, Spain Baide, Dajiang, Italy flange, Italy high, Britain Maxon, France VISO, America Liwei, Germany Olin, etc. The key well-known brands of domestic burners include Zhejiang Baite, curate, Baite, etc. Our company generally strongly recommends the application of imported burners, and the key factors are reliability, safety factor, high efficiency, and so on.
2. The natural material selection burner is divided into different key parts according to the ignited natural material.
3. The mode of model selection is mainly to select the thermal power of the combustion engine according to the thermal power rate of the boiler (the model is determined by the thermal power of the combustion engine)
The model selection method is mainly to select the thermal power of the burner according to the thermal power rate of the heating furnace (the model specification is determined by the thermal power of the burner). 1. The calculation method of the output power of the burner: the output power of the burner = the output power of the heating furnace / the thermal effect. The model specification of the burner is defined, and the working pressure and total flow of the appropriate burner must be selected according to the specific conditions. Natural gas burner: specified total natural gas flow [M3N / h] = (burner output power [kW] × 3.6) / [heat generation of steam body MJ / M3N]; Gasoline and diesel burner: demand for total flow of gasoline and diesel [kg / h] = (burner output power [kW] × 3.6) / calorific value of gasoline and diesel [MJ / kg]. 2. Selection of valve groups for natural gas and dual fuel burners (key for natural gas boilers): the valve group selection table shall be used to select valve groups with sufficient specifications. It must be noted that the standard value of the valve group selection table is the data information when the back pressure of the heating furnace is 0. When selecting the valve group, the specific natural gas working pressure must be reduced by the back pressure of the heating furnace to select the valve group. The steam body in the valve group selection table is gas. 3. Check the connection specification of the burner, especially that the ignition head must be suitable for the heating furnace. The length of the ignition head in the heating furnace should be 10-20mm above the fire throat of the ignition head. Check the specification of the fire in the fire size drawing. Please pay attention that the fire cannot touch the furnace’s mouth.
After the transformation of the low NOx burner, although the NOx decreases greatly, even when the same kind of coal is used, the increase of fly ash combustibles is also large. The low nitrogen combustion technology mainly adopts low temperature and low oxygen combustion, and the temperature in the main combustion area drops more, so as to control and delay the ignition of pulverized coal, and reduce the oxygen content in the ignition area, so as to reduce the burnout capacity of pulverized coal, prolong the combustion process, and increase the combustibles of fly ash and slag. In some retrofits, the area of the primary and secondary air nozzles and the burnout air nozzle of the burner are changed, resulting in the delay in the mixing of the secondary air and the primary air, which is not conducive to the ignition and combustion of the pulverized coal flow. According to the test data of the reformed boiler, the rise of fly ash combustibles of the tangential firing boiler is 0.5-1 percentage point, the rise of fly ash combustibles of the opposed firing boiler is 1-1.5 percentage points, and the rise of fly ash combustibles of the “W” flame burning boiler is 2-4 percentage points, which affects the decrease of boiler efficiency by 0.4-1.6 percentage points.
In a word, customers should combine the scientific research and selection of the gasoline and diesel gas heating furnace according to their own specific conditions to ensure high efficiency, environmental protection and energy saving, and stable and suitable gasoline and diesel gas heating furnace.