Compound furnace arch and compound secondary air structure for cooperatively controlling generation of nitrogen oxide (NOX)

Abstract

The invention relates to a compound furnace arch and a compound secondary air structure for cooperatively controlling generation of an NOX. A front arch water cooled furnace wall protrudes into a furnace to form a cavity with a fire-resistant front arch, an ejector is arranged at the throat portion of the front arch to eject volatiles, a compound secondary air device is arranged at the throat portion of a rear arch, and a nozzle of the ejector and a rear arch secondary air horizontal nozzle are arranged at an interval horizontally and oppositely. Compared with the prior art, according to the compound furnace arch and the compound secondary air structure for cooperatively controlling generation of nitrogen oxides, the volatiles are drawn out from the cavity between the front arch furnace wall and the front arch water cooled furnace wall and reacted with the NOX in high temperature flue gas, simultaneously high temperature ammonia jetting can be achieved during deep removal of NOX, so that technology integration of actively and cooperatively removing the NOX of stage combustion of fuels of the compound front arch and the ejector, stage combustion of compound secondary air and volatile re-burning is achieved, NOX emission levels of chain grate furnaces or grate-fired furnaces using similar principles are obviously reduced, and standard emission of the NOX of industrial grate-fired furnaces is achieved.

Description

technical field [0001] The invention belongs to the technical field of controlling nitrogen oxide emissions of a layer-fired boiler, and in particular relates to a composite furnace arch and composite secondary air structure for synergistically controlling the generation of nitrogen oxides. Background technique [0002] Since 2000, with the development of my country's industrialization and urbanization, the improvement of energy conservation and environmental protection requirements, and the huge increase in urban heating demand, large-capacity layer-fired coal-fired central heating boilers have entered a period of rapid development. Among the coal-fired industrial boilers in my country, the layer-fired chain boilers account for more than 60% of the total number of industrial boilers. Therefore, the energy saving and emission reduction of chain boilers is the top priority of energy saving and emission reduction of industrial boilers in my country. In the design and operatio...

AI Technical Summary

Problems solved by technology

This traditional furnace arch structure can significantly improve the combustion efficiency of the boiler, but because it highlights the importance of ignition and enhanced combustion, it ignores the source of NO produced during the combustion process. X Active control technology research and development, lack of active control NO X Generated relevant structural design technology, and for industrial boilers, if the NO can not be actively controlled X generation, we can only use ammonia injection technology on the upper part of the furnace or implement SCR flue gas denitrification post-treatment technology, etc., while ammonia injection removes NO X Although the technology is simple, the removal efficiency is low, ammonia, urea and other substances are consumed all the time, and the operating cost is high

As for SCR, not only ammonia injection, but also the use of expensive catalysts to accelerate the removal reaction, the operating cost is higher

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