Forward and backward wall opposite rushing combustion boiler hearth as well as method for arranging air nozzle on side wall

Abstract

The invention pertains to forward and backward wall opposed firing type utility boiler combustion chamber and method for arranging air nozzle on its side. The combustion chamber comprises a pulverized coal burner, forward and backward walls of combustion chamber of combustion wind combustor group, and a combustion chamber body arranged with air nozzle group including two-sided wall, and a combustion chamber hopper at lower part of the combustion chamber body. The method arranging air nozzle on its side is to arrange 1-6 row of air nozzles above the intersecting line of lowest pulverized coal burner shaft cross section and two-sided wall, and symmetrical with side wall centre line. By arranging a nozzle cluster capable of supplying axial flow air and side flow air to the combustion chamber on two-sided walls at same time, the invention can reduce side wall temperature at same time of improving oxygen compensation strength and boiler thermal efficiency, can effectively prevent the two-sided walls from severe coking and high-temperature corrosion, can reduce examination and repair amount of work of combustion chamber and can prolong service-life. The invention overcomes disadvantages of low combustion efficiency, severe coking and high-temperature corrosion of the two-sided walls in background art.

Description

technical field [0001] The invention belongs to a power station boiler furnace and a method for arranging air nozzles on its side wall. In particular, it relates to a furnace of a combustion type utility boiler whose front and rear walls oppose each other and a method for arranging air nozzles on both side walls of the furnace. Background technique [0002] At present, with the development of boilers towards large capacity and high parameters, the advantages of wall-fired boilers in terms of combustion equipment and heating surface layout are becoming more and more obvious. The staged combustion method with the front and rear walls facing each other shows the advantages of smaller thermal deviation of the superheater and reheater than the tangential circular combustion method, better flame filling in the furnace, strong disturbance, and can effectively reduce NOx emissions. Through the in-depth research of the front and rear wall opposed combustion furnace and the accumulat...

AI Technical Summary

Problems solved by technology

During the operation, it was found that in terms of the heat load of the walls (water-cooled walls) around the furnace, the average load and the local maximum heat load of the water-cooled walls on both sides were higher than those of the front and rear walls, and at the same time, it was high near the middle area of ​​the inner surface of the water-cooled walls of the side walls. CO concentration and low O 2 Concentration area presents an obvious reducing atmosphere, causing serious coking and high-temperature corrosion of the water wall in this area; (air) It is extremely difficult to meet the oxygen supply requirements in the central area of ​​the furnace, especially the central area near the two side walls, which also affects the combustion efficiency and service life of the boiler

Therefore, this type of boiler furnace has poor oxygen supply in the central area of ​​the furnace during operation, especially near the central area on both sides of the wall, high CO concentration, low combustion efficiency, serious coking and high-temperature corrosion on both sides of the wall, heavy maintenance workload and affects the furnace. Defects such as service life

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