Dissertation > Excellent graduate degree dissertation topics show

Experimental Research on Low NO_X Combustion Technology Reform by SOFA Method of a 420t/h Boiler

Author: LuZhi
Tutor: ZhouZhiJun；LiuJianZhong
School: Zhejiang University
Course: Engineering Thermophysics
Keywords: NO_x thermal balance subsiding furnace SOFA numerical simulation
CLC: TK16
Type: Master's thesis
Year: 2008
Downloads: 94
Quote: 2
Read: Download Dissertation

Abstract


With the acceleration of industrialization process and the development of the power industry, the consumption of coal was increasing year by year. The combustion of fuels generate more and more NO_X emission, which can lead to serious atmosphere pollution. Control of the combustion and pollution of power plant were important for the sustainable development of our country.A Corner-tangential-boiler of 420t/h in Xiaoshan thermal power plant was studied in the thesis by means of experiments and field tests and numerical simulation, then the low NO_X Combustion Technology reform sheme by SOFA method was designed.Through the method of the thermo gravimetric analysis, studied the factor that influencing the coal combustion characteristic, including the ignition and combustion characteristic, analyzed the coal kind and elevation of temperature speed. The results revealed that the ignition temperature、steady combustion numeric and burnout index of different coal types had obvious difference.The ignition-temperature of dahun35002 was 363°C ,which was the lowest one of the coal samples, The ignition-temperature of dahun35007 was 424℃,which was the highest one of the coal samples,the discrepancy between them was greater than 60℃;The law of steady combustion numeric was the same as The law of ignition-temperature. The burnout index of dahun35007 was 145.31, which was the highest one of the coal samples,the burnout index of dahun106 and zhunhun was 120.31 and 124.40 respectively,The Combustion Efficiency of dahun35002 was the poorest, The burnout index of it was only 71.03.The Experimental Investigation on the influence of different excess air factor and temperature on the NO_x emission characteristics of different coal types was carried out on subsiding furnace, and their causes analyzed. By comprehensive consideration of NO_x emission and the coke burnout,the excess air factor in the main combustion zone was controlled at 0.85.When the furnace temperature was over 1300℃,the NO_x emission was greatly increased either in the oxidizing atmosphere or in the reducing atmosphere,so the temperature of main combustion zone had best controlled below 1300℃.Hot state tests on the NO_X emission of the boiler was carried out. When the boiler operated at low load,the oxygen concentration was over high,then causing NO_X emission too highly.When two coal mills operated, Tertiary-Air Coal Rebuming reduced NO_X Release.When the oxygen concentration was below 3%,NO_X emission increased greatly as the oxygen concentration rised. When the oxygen concentration was above 3%,the increasing rate was easting up.For the existing burner, pulverized coal distribution had little influence on NO_X emission. Ensuring primary air Stable,on this premise,low primary air velocity can lower the NO_X emission. For the existing burner, optimizing air distribution only had limited influence on NO_X emission.Based on the test result,two low NO_X and combined with practical boiler operation,two low NO_X reform schemes was desighed,then a predicton of reform scheme combustion and NO_X emission was made by numerical simulation.The simulation results showed that the boiler operated stably; the temperature field was uniformity; complete combustion was reached, NO_x emission reduced greatly,and the scheme one had better reconstruction effect than the scheme two.

Related Dissertations

  1. The Setting Bases of Working Pressure in LNG Systems and Orthogonal Experiment Design of Heat Exchangers,TQ051.5
  2. Study on Springback of High-Strength Steel Stamping,TG386
  3. Numerical Simulation and Experiment on Hydroforming of Cups with Controllable Radial Pressure,TG386
  4. Research on Technology and Mechanism of Joining Cemented Carbide to Carbon Steel,TG454
  5. Experimental Research on Influence of Coal Reburning Reaction Conditions on NO_x Reduction by Non-Catalytic Reduction of Ammonia,X701
  6. The Effect of Composite Additive on the SNCR,X701
  7. Numerical Simulation of Film Cooling in Turbine Cascade with Non-Axisymmetric Endwall Method,V231.3
  8. High Speed Aerodynamic Convection and Coupled Heat Transfer of Complicated Bodies,V215.4
  9. The Analysis on Characteris of Vibration Source about Vertical Vibration of Surrounding Environment Induced by Rail Transit,U211.3
  10. Study of Method and Facilities for Transfering from Hot Air to Exhaust Air Converying System,TK223.25
  11. Study on the Heat Transfer Characteristics of Particle Cluster in Circulating Fluidized Bed,TK124
  12. Numerical Simulation of SNCR Process of a 600MW Utility Boiler,TK222
  13. Numerical Simulation of Biomass Direct Reburning,TK16
  14. Numerical Simulation on Pulverized Coal Combustion Process in a 670T/H Tangential Firing Furnace,TK224.11
  15. Numerical Simulation on the Combustion Process in the Furnace of a 1000MW Lignite-Fired USC Boiler,TK224.11
  16. Study on Gas-Solid Two-Phase Flow in Spouted Beds,TK173
  17. Experimental Study and Numerical Simulation on Aerodynamic Field of Tangential Bias Swirl Burner,TK223.23
  18. Characteristic Study of Combustion in Central Reverse Flame Chamber,TK223.21
  19. Numerical Simulation and Contrastive Analysis of Labyrinth Seals and Leaf Seals,TK263.2
  20. Numerical Study on Phosphorus Distribution in Water Environment of the Three Gorges Reservoir,X832
  21. The Design and Performance Simulation of External Valve Small Displacement Pump,TE933.3

CLC: > Industrial Technology > Energy and Power Engineering > Thermal engineering, heat > Fuel and combustion
© 2012 www.DissertationTopic.Net  Mobile