Coupling Of High-temperature Corrosion And Erosion Wear Studies Under Wall Tangentially Fired

Clean and efficient power generation technology is our power industry’s maindirection, while SC (USC) is one of it. As the development of power plant boilertoward large capacity and high parameter, the temperature and pressure are furtherimproved. What’s worse, the boiler heating surface especially water wall operatingenvironment is becoming more serious. Air classification combustion technologycan effectively control NOX’s emission, but in poor fuel combustion furnace waterwall prolonged reduction zone in a reducing atmosphere, corrosive flue gases andsolid particles carried in the heating surface will cause corrosion and erosion andother issues.In this paper, to aim at the invalid phenomenon of a660MW supercritical boilerwater wall burner region, checked the appearance of invalid water wall, the wall isvery smooth and has an obviously thinner. We can make an initial conclusion thatthere are erosion on the water wall. Then the sample were analyzed by XRD、SEM、EDS, test results show that the water wall surface simultaneously S corrosion. Inshort, final determination of the region is the failure of water wall erosion corrosionand lower coupling caused.Reduction zone of the boiler water wall failure solution ideas to reduce furnaceinscribed circle diameter, reduce flue gas velocity near the wall, as well as toimprove the reduction zone near the wall of the oxygen content. The initialrehabilitation programs are as follows: the primary air of the up burner group insideoffset; the primary and secondary air of the up burner group both inside offset; theup burner group inside move.In order to verify the correctness of the test analysis and get a reasonable solutionto this paper, firstly carried out the numerical simulation study of the boilers burningdesigned coal and actual coal. The results showed that because of the actual coal’ssulfur content and ash content were higher, the H2S concentration near the waterwall were higher and the flue gas velocity were a little higher, which correspondingto the analytical results. Then carried out the numerical simulation study of theinitial rehabilitation programs, the simulation shows that when the primary air of theup burner group inside offset, the oxygen concentration near the water wall werehigher, the flue gas velocity were lower. Lastly carried out numerical simulationstudy of the different deflection angle, with the change of the primary air nozzlesbias from0°to12°,the oxygen concentration increaser, but compared8°and 12°,the H2S concentration has little changed. When the primary air nozzles is8°,the near wall’s flue gas velocity is lowest. Summary, the best rehabilitationprogram is primary air inside offset8°.