A bottom-mounted low-nitrogen burner suitable for large-scale load adjustment

Abstract

The invention relates to a bottom-mounted low-nitrogen combustor suitable for large-range load adjustment. The bottom-mounted low-nitrogen combustor comprises a center flame adjusting pipe, a primary air pipe, a secondary air pipe and a tertiary combustion supporting device, all of which are sequentially arranged from inside to outside in a sleeved manner. A coal dust flow stabilizing mechanism is arranged at an inlet of the primary air pipe, and a primary air cyclone is arranged at an outlet of the primary air pipe. An air premixing device is arranged at an inlet of the secondary air pipe, and a secondary air cyclone is arranged at an outlet of the secondary air pipe. A flame stabilizing device is further arranged at an outlet of the secondary air pipe. An air outlet of the tertiary combustion supporting device communicates with the flame stabilizing device. According to the bottom-mounted low-nitrogen combustor, due to the reasonable arrangement of the structure, classified combustion can be achieved, the load adjustment range of the combustor is greatly enlarged, the adaptability of the combustor to different conditions in the industry is improved, a low-nitrogen combustion technology is adopted, the initial emission index of the combustor is far lower than the emission condensation of the natural regulation, and the beneficial effects of high efficiency, energy conservation, emission reduction and environment friendliness are achieved.

Description

technical field [0001] The invention relates to a bottom-mounted low-nitrogen burner suitable for large-scale load adjustment, which belongs to the technical field of coal-fired systems. Background technique [0002] In our country, industrial boilers and small and medium-sized heating boilers have high and low load operation in the actual operation process, especially for industrial boilers. According to the needs of industrial production changes, the boiler load is adjusted from time to time to ensure that its heat supply does not exceed the standard. [0003] At present, the industrial coal-fired boiler system in our country has a relatively small load adaptation range, generally within the load adjustment range of 50%-80%. For production units, due to the reduced production volume, there is often ultra-low load operation of the boiler. At this time, the measures taken by the boiler are generally to start and stop the boiler frequently, or to operate under pressure (chain...

AI Technical Summary

Problems solved by technology

[0004] At present, the existing technology is that when the coal-fired boiler is under low load, the outlet size of the burner is fixed, and reducing the amount of pulverized coal requires a corresponding reduction in the air volume ratio. Flow-type pulverized coal burners, due to insufficient swirl strength, lead to poor coal pulverized combustion rate, and easy to form local high temperature, resulting in a large amount of NOx

During high-load operation, due to the fast wind speed at the burner outlet and the high swirl intensity, the high-temperature flue gas backflow will cause the central flame temperature to be too high, which will easily cause problems such as coking, uncontrollable thermal nitrogen, and excessive NOx emissions.

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