Appliedresearch Of Low Nitrogen Coaxialburner In 600 MW Boiler

With the continuous development of the economy, on the one hand, people more and more high to the requirement of environmental protection, NOxemissions coal-fired power plant has been more and more can't meet the requirements of environmental protection;On the other hand the grid load capacity of coal-fired power plant are put forward higher request, requirement of boiler under lower load not only ensure the efficiency and stability of combustion, and at the same time further reduce nitrogen oxide.This paper introduces the development history of boiler burner and classification, and details the current relatively popular in the four features: combustion technology graded combustion technology, low-load stable-combustion technology, the four tangential combustion technology and hedge combustion technology, and in my Jin Wan power plant boiler as an example, details the features and applications of low NOx coaxial combustion system.Based on the mechanism of NOx formation and adopt the air classification and grade of fuel combustion, flue gas recirculation, and low nitrogen combustion chamber and other advanced combustion technology, reduce the pulverized coal combustion process in the production of nitric oxide, forming a new combustion technology--coaxial low nitrogen combustion technology.Compared with previous combustion technology, the technology design and manufacture of simpler, late upfront investment cost and operation maintenance cost is lower, is a more promising and more economic and effective combustion technology.Jin Wan power plant by using low NOx coaxial combustion system has achieved expected combustion efficiency and lower stable-combustion load, but there is still a change to unit load, phase under low load, the dynamic process of different types of NOx emissions rise rapidly, the combustion efficiency is lower, left and right side,reheater steam temperature deviation problem such as reduction of large amount of warm water.In order to reduce NOx emission of the unit, improve the overall efficiency and environmental protection of the unit, the plant from the various factors of influenced NOx, and units in 240 mw ~ 600 mw load range, for the adjustment of the burner angular, SOFA, the wind of the adjustment, the adjustment of the pulverized coal fineness, the adjustment of the oxygen, auxiliary air nozzle of the wind, fuel adjustments, CCOFA wind opening adjustment.Finally solved the low NOx coaxial NOx emissions rising fast in the system of burning, combustion efficiency, lower, left and right side of the steam temperature deviation is big, reheater of large amount of warm water reduction, and many other issues, the boiler even in the dynamic process of load change has remained low NOx emissions and keep stable combustion at low load stage, when they are in different coal combustion can reach high combustion efficiency, adaptability, coal boiler load adaptability have been greatly improved.Finally make it is concluded that the best way to run a function relation in the control logic, realize the automatic optimization control unit, and in the later observing, according to the actual operation situation to make the adjustment of the trace, then boiler always run in optimal condition.