摘要
【目的】电站锅炉在燃用准东煤时会出现严重的受热面沾污结渣问题,为此,对准东煤灰在受热面上的沉积和脱落特性进行了研究。【方法】建立了基于颗粒黏附能的沉积灰侵蚀模型,对准东煤灰在单管上的动态沉积和脱落过程进行了数值模拟研究。【结果】耦合侵蚀机理的模型模拟结果与实验结果之间的误差仅为3.3%,展现出较高的精确度。此外,沉积灰的脱落速率呈先增大后趋于平缓的趋势,但在所模拟的时间范围内仅能使25%的沉积灰脱落。与此同时,沉积灰的累积使受热面的传热损耗速率逐渐增大,6 h时间段内的平均传热损耗速率为1 h时间段的1.76倍。另外,6 h沉积灰的黏附能为1 h的6.11倍,相应的吹灰出口空气质量流率需要提高1.85倍才能有望清除全部的积灰。【结论】研究结果加深了对准东煤灰动态沉积和脱落过程的认识,为工业上的吹灰优化提供了重要研究数据和理论支撑。
[Objectives]Power plant boilers often experience severe fouling and slagging issues on the heating surfaces when burning Zhundong coal.Therefore,the deposition and shedding characteristics of Zhundong coal ash on the heating surface were studied.[Methods]A deposited ash erosion model based on particle adhesion energy is established,and numerical simulations are then conducted to examine the dynamic deposition and shedding processes of Zhundong coal ash on a single tube.[Results]The model incorporating the coupled erosion mechanisms has a deviation of only 3.3%compared to the experimental results,demonstrating high accuracy.Besides,the shedding rate of the deposited ash increases initially but then levels off.However,within the simulated timeframe,only 25%of the deposited ash can be removed.In addition,the accumulation of deposited ash leads to a gradual increase in the heat transfer loss rate of the heating surface,with the average heat transfer loss rate during a 6-hour period being 1.76 times that of a 1-hour period.Furthermore,the adhesion energy of the deposited ash after 6 hours is 6.11 times that after 1 hour,and the corresponding mass flow rate of air at the soot-blowing outlet needs to be increased by 1.85 times to effectively remove all the deposited ash.[Conclusions]These findings enhance the understanding of the dynamic deposition and shedding processes of Zhundong coal ash and offer important research data and theoretical support for optimizing sootblowing operations in industrial applications.
作者
郭前鑫
李建波
王虎
梁银堂
韩新建
阮雄伟
卢啸风
GUO Qianxin;LI Jianbo;WANG Hu;LIANG Yintang;HAN Xinjian;RUAN Xiongwei;LU Xiaofeng(Guoshen Technical Support Center,CHN ENERGY Investment Group Co.,Ltd.,Xi’an 710000,Shaanxi Province,China;Key Laboratory of Low-Grade Energy Utilization Technology and System(Chongqing University),Ministry of Education,Shapingba District,Chongqing 400044,China)
出处
《发电技术》
2025年第4期829-838,共10页
Power Generation Technology
基金
国家自然科学基金项目(52176101)。
关键词
煤电
准东煤
积灰
侵蚀脱落
平均黏附能
数值模拟
碱金属
吹灰
coal-fired electricity
Zhundong coal
ash deposition
erosion and shedding
average adhesion energy
numerical simulation
alkali metal
soot blowing
