Numerical analysis on combustion process and sodium transformation behavior in a 660 MW supercritical face-fired boiler purely burning high sodium content Zhundong coal |
| |
| Affiliation: | 1. School of Energy Science and Engineering, Harbin Institute of Technology, Harbin, 150001, PR China;2. Liaoning Provincial Key Laboratory for Urban Ecology, Shenyang Academy of Environmental Sciences, Shenyang, 110167, PR China;1. MOE Key Laboratory of Thermo-Fluid Science and Engineering, Xi’an Jiaotong University, Xi’an 710049, China;2. Institute of Thermal Energy Engineering, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China;1. State Key Laboratory of Multiphase Flow in Power Engineering, School of Energy and Power Engineering, Xi’an Jiaotong University, Xi’an, 710049, China;2. Yulin University, Yulin 719000, China;1. State Key Laboratory of Coal Combustion, School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, PR China;2. Key Laboratory of Coal Clean Conversion & Chemical Engineering Process, Xinjiang Uygur Autonomous Region, College of Chemistry and Chemical Engineering, Xinjiang University, Urumqi 830046, PR China;1. Institute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100190, China;2. University of Chinese Academy of Sciences, Beijing 100049, China;3. Dalian National Laboratory for Clean Energy, Dalian 116023, China |
| |
| Abstract: | CHEMKIN software was used to optimize the reaction mechanism of sodium in flue gas to study the influence of targeted design for purely burning Zhundong (ZD) coal on boiler characteristics. Then, the optimized 32-step elemental reaction was combined with CFD software. An eddy-dissipation concept model considering detailed chemical reactions was used to simulate the transformation behavior of sodium-containing substances. The combustion characteristics of the 660 MW face-fired boiler under various loads were also simulated. The field distribution in the furnace and the migration path of sodium along the track of pulverized coal particles were obtained. The results show that the interference between each burner in the furnace is small at the BMCR load, and the phenomenon of “wind wrapping fire” is distinctly clear. The temperature at furnace outlet is approximately 970.98 °C. At a low load, the combustion in the furnace is stable, and the temperature at the furnace outlet reaches the design value. The sodium present in ZD coal is involved in the reaction after it is released in the form of Na and NaCl. Sodium is present in different forms in the main burner zone, mainly NaCl (67%), NaOH (12%), Na (9%), and Na2SO4 (7%). The forms of sodium at the furnace outlet are NaCl (50%), Na2SO4 (37%), Na2Cl2 (9%) and NaHSO4 (4%). A small amount of Na2SO4 is formed by NaHSO4 reaction in the main burner zone. It then reacts to form NaSO4, wherein NaHSO4 is formed by path 2. Na2SO4 is mainly generated in the burnout zone through path 1, and paths 2, 3, and 4 are hardly observed. The findings of this research can provide reference for the design of a purely fired ZD coal boiler and further studies on slagging observed on the heating surface. |
| |
| Keywords: | Zhundong coal Sodium transformation behavior Combustion characteristics CHEMKIN CFD |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
