Pulverized coal burner for pulverized coal collection and concentration, and burning method

Abstract

The invention relates to a pulverized coal burner for pulverized coal collection and concentration and a burning method. The burner comprises a nozzle main body (1) and an airflow inlet pipeline (5). The airflow inlet pipeline (5) is of a structure with an equal diameter. A conduit (4) with various diameters is arranged between the nozzle main body (1) and the airflow inlet pipeline (5). An upper pulverized coal collection flame holder (3) and a lower pulverized coal collection flame holder (2) are respectively arranged on the interior of the nozzle main body (1) and tightly attached to the upper wall face and the lower wall face of the nozzle main body (1). The upper pulverized coal collection flame holder (3) is of a step-shaped structure with the cross section gradually reducing from top to bottom. Correspondingly, the lower pulverized coal collection flame holder (2) is of a step-shaped structure with the cross section gradually reducing from bottom to top. The through-flow sectional areas of the conduit (4) with various diameters gradually become larger along the airflow direction. The pulverized coal burner for pulverized coal collection and concentration and the burning method have the advantages that pressure of an airflow flow path is changed through adjustment of the shape of the cross section of an airflow channel, and therefore the flow direction of partial air in the pulverized coal airflow is changed, and separation of air and pulverized coal is achieved.

Description

technical field [0001] The invention relates to the field of pulverized coal combustion equipment, in particular, the invention relates to a pulverized coal burner and a combustion method for collecting and concentrating pulverized coal. Background technique [0002] Concentration of pulverized coal and enhanced flue gas reflux heating are the core technology to improve the combustion performance of pulverized coal. Concentrating primary air pulverized coal can reduce the heat of ignition. Under the enhanced flue gas reflux heating, it is easier to achieve stable combustion and reduce NO x emissions are beneficial. To this end, people have developed a variety of burners with coal concentration and enhanced flue gas reflow heating capabilities. [0003] The scheme of pulverized coal concentration can be roughly divided into external spout type and spout built-in type. The scheme of external pulverized coal concentration includes elbow separator, louver separator, impactor s...

AI Technical Summary

Problems solved by technology

[0005] The applicant provided a low nitrogen oxides pulverized coal decoupling burner and its combustion method in the patent application with application number 201110033811.8. In this patent application, the primary variable-section tube and the secondary variable-section tube And the powder collecting and flame stabilizing device, and in the main body of the nozzle shell, there are four upper light powder channel, lower light powder channel, left secondary diversion area and right secondary diversion area formed by the upper, lower, left and right spaces of the powder collecting flame stabilizer channel, with the first-stage variable-section tube and the second-stage variable-section tube to realize the decoupling combustion of pulverized coal, but the decoupling combustion of coal powder in this device must pass through the first-stage variable-section tube and the second-stage variable-section tube The tube cooperates with the four channels, the structure is complex, the air flow turns many times, the resistance is relatively large, there are many parts prone to wear, and the maintenance is also difficult. It is more suitable for refractory coal with high performance requirements. The cost performance of coal is not high

Images