化工学报 ›› 2022, Vol. 73 ›› Issue (2): 923-932.doi: 10.11949/0438-1157.20210887

• 能源和环境工程 • 上一篇    下一篇

超低排放燃煤机组硒的迁移转化及飞灰对其富集特性

刘轩1(),苏银皎1,滕阳1,张锴1(),王鹏程2,李丽锋2,李圳2   

  1. 1.华北电力大学热电生产过程污染物监测与控制北京市重点实验室，北京 102206
    2.山西河坡发电有限责任公司，山西 阳泉 045011
  • 收稿日期:2021-06-30 修回日期:2021-10-19 出版日期:2022-02-05 发布日期:2022-02-18
  • 通讯作者: 张锴 E-mail:15210289575@163.com;kzhang@ncepu.edu.cn
  • 作者简介:刘轩（1994—），男，博士研究生，15210289575@163.com
  • 基金资助:
    国家自然科学基金联合基金重点项目(U1910215)

Selenium transformation in ultra-low-emission coal-fired power units and its enrichment characteristics in fly ash

Xuan LIU1(),Yinjiao SU1,Yang TENG1,Kai ZHANG1(),Pengcheng WANG2,Lifeng LI2,Zhen LI2   

  1. 1.Beijing Key Laboratory of Emission Surveillance and Control for Thermal Power Generation, North China Electric Power University, Beijing 102206, China
    2.Shanxi Hepo Power Generation Company Limited, Yangquan 045011, Shanxi, China
  • Received:2021-06-30 Revised:2021-10-19 Published:2022-02-05 Online:2022-02-18
  • Contact: Kai ZHANG E-mail:15210289575@163.com;kzhang@ncepu.edu.cn

RichHTML

4

PDF (PC)

36

摘要：

采用微波消解法和氢化物发生-原子荧光光谱法考察了9台超低排放在役机组硒迁移转化规律，探究了循环流化床（CFB）和煤粉炉（PC）机组飞灰特性差异对硒吸附能力的影响。燃烧后煤中硒几乎全部呈现挥发态，底渣中残留量极低。与浓度归一化和质量分布法相比较，相对富集系数法可以客观地评价燃煤副产物中硒的富集能力，两类机组中硒均主要富集于飞灰中。CFB较低炉膛温度和添加CaO可以降低入炉煤中硒释放比例并增强飞灰对硒的吸附能力，故其底渣和飞灰中硒的富集程度均高于PC，导致脱硫石膏中硒富集程度低于PC。飞灰对硒的吸附量随比表面积或孔容积增大而增大，但随粒径或孔径增大而减小。CFB飞灰中未燃尽碳含量高、形状不规则、表面粗糙且存在较多蜂窝状孔隙，导致其对硒的富集程度高于PC飞灰。

关键词: 煤燃烧, 污染, 硒迁移转化, 微波消解, 吸附

Abstract:

Microwave digestion and hydride generation-atomic fluorescence spectrometry were used to investigate the migration and transformation of selenium (Se) in nine ultra-low emission units in service. The characteristics of fly ash from circulating fluidized bed (CFB) and pulverized coal (PC) units are compared for understanding the Se adsorption ability in fly ash. After combustion, Se in coal is essentially volatilized in gas but only a small amount is remained in bottom slag. Compared to concentration normalization method and mass distribution method, relative enrichment factor method is more suitable to evaluate the Se enrichment ability for feed coal and combustion by-products, which indicates that Se is enriched in fly ash from both CFB and PC units. Low combustion temperature and CaO additive in CFB boiler can not only reduce Se release ratio from coal but also enhance the Se adsorption ability in fly ash. As a result, Se enrichment in bottom slag and fly ash from CFB is more than that from PC, while Se in gypsum from CFB unit is less than that of PC. Moreover, Se adsorption content is heavily depended on the physical properties of fly ash. The amount of selenium adsorbed by fly ash increases with the increase of specific surface area or pore volume, but decreases with the increase of particle size or pore size. The fly ash from CFB unit has high unburned carbon content, irregular shape, rough surface and more honeycomb pores, which makes Se enriched in fly ash from CFB more than that of PC.

Key words: coal combustion, pollution, selenium migration and transformation, microwave digestion, adsorption

中图分类号: 

  • TQ 53

表1

所选燃煤机组容量、类型及取样类型"

机组编号机组容量烟气尾端污染物控制设备取样点
CFB1135 MWSNCR+FF+WFGD入炉煤+底渣+飞灰
CFB2200 MWSCR+FF+WFGD入炉煤+底渣+飞灰+脱硫石膏
CFB3300 MWSNCR/SCR+FF+WFGD入炉煤+底渣+飞灰+脱硫石膏
CFB4300 MWSNCR+FF+WFGD入炉煤+底渣+飞灰+脱硫石膏
PC1300 MWSCR+ESP+WFGD入炉煤+底渣+飞灰+脱硫石膏
PC2330 MWSCR+ESP+WFGD+WESP入炉煤+底渣+飞灰+脱硫石膏
PC3350 MWSCR+ESP+WFGD+WESP入炉煤+底渣+飞灰+脱硫石膏
PC4600 MWSCR+ESP+WFGD+WESP入炉煤+底渣+飞灰+脱硫石膏
PC5600 MWSNCR/SCR+FF/ESP+WFGD+WESP入炉煤+底渣+飞灰+脱硫石膏

图1

燃煤电厂入炉煤及副产物中硒平均含量"

表2

燃煤机组入炉煤工业分析"

燃煤机组入炉煤工业分析/%(质量,空气干燥基)
水分灰分挥发分固定碳
CFB12.2341.5029.7226.55
CFB21.2461.2018.6218.94
CFB32.3633.9624.9438.74
CFB42.3839.7624.7433.12
PC10.9041.6712.2645.17
PC21.2529.3210.6758.76
PC32.6715.0529.9552.33
PC43.9816.4225.5754.03
PC52.8329.6727.3240.18

图2

飞灰和底渣与入炉煤中硒含量的比值"

图3

飞灰和底渣中硒质量分布"

图4

飞灰和底渣中硒相对富集系数"

图5

不同粒径飞灰中硒含量"

图6

不同粒径飞灰中未燃尽碳含量"

图7

CFB4和PC1机组不同粒径飞灰吸附和脱附等温曲线"

图8

CFB4机组和PC1机组飞灰SEM图"

图9

不同粒径飞灰中硒吸附含量与其比表面积关系"

图10

不同粒径飞灰中硒吸附含量与其孔容积关系"

图11

CFB4机组和PC1机组不同粒径飞灰中硒吸附含量与其孔径关系"

图12

CFB4机组和PC1机组不同粒径飞灰孔容积分布图"

1 Rayman M P. Selenium and human health[J]. The Lancet, 2012, 379(9822): 1256-1268.
2 张敏明, 袁林喜, 尹雪斌, 等. 人体发硒水平影响因素研究进展[J]. 生物技术进展, 2017, 7(3): 187-192.
Zhang M M, Yuan L X, Yin X B, et al. Review on influence factors of selenium levels in human hair[J]. Current Biotechnology, 2017, 7(3): 187-192.
3 Song G C, Xu W T, Liu K, et al. Transformation of selenium during coal thermal conversion: effects of atmosphere and inorganic content[J]. Fuel Processing Technology, 2020, 205: 106446.
4 周新越, 吴洋文, 密腾阁, 等. 燃煤烟气重金属与铈改性CaO的相互作用机理研究[J]. 燃料化学学报, 2020, 48(12): 1520-1529.
Zhou X Y, Wu Y W, Mi T G, et al. Interaction mechanism between heavy metals and Ce-doped CaO in flue gas of coal combustion[J]. Journal of Fuel Chemistry and Technology, 2020, 48(12): 1520-1529.
5 苏银皎, 刘轩, 李丽锋, 等. 三类煤阶煤中汞的赋存形态分布特征[J]. 化工学报, 2019, 70(4): 1559-1566.
Su Y J, Liu X, Li L F, et al. Distribution characteristics of mercury speciation in coals with three different ranks[J]. CIESC Journal, 2019, 70(4): 1559-1566.
6 吴舜泽, 孙宁, 卢然, 等. 重金属污染综合防治实施进展与经验分析[J]. 中国环境管理, 2015, 7(1): 21-28.
Wu S Z, Sun N, Lu R, et al. The progress and empirical analysis on the implementation of comprehensive prevention and control of heavy metal pollution[J]. Chinese Journal of Environmental Management, 2015, 7(1): 21-28.
7 Wang J, Nakazato T, Sakanishi K, et al. Microwave digestion with HNO3/H2O2 mixture at high temperatures for determination of trace elements in coal by ICP-OES and ICP-MS[J]. Analytica Chimica Acta, 2004, 514(1): 115-124.
8 Iwashita A, Nakajima T, Takanashi H, et al. Effect of pretreatment conditions on the determination of major and trace elements in coal fly ash using ICP-AES[J]. Fuel, 2006, 85(2): 257-263.
9 Gómez-Ariza J L, Sánchez-Rodas D, Giráldez I, et al. A comparison between ICP-MS and AFS detection for arsenic speciation in environmental samples[J]. Talanta, 2000, 51(2): 257-268.
10 施正伦, 骆仲泱, 周劲松, 等. 石煤流化床燃烧重金属排放特性试验研究[J]. 煤炭学报, 2001, 26(2): 209-212.
Shi Z L, Luo Z Y, Zhou J S, et al. Experimental research on heavy metals emission from fluidized bed with stone coal fired[J]. Journal of China Coal Society, 2001, 26(2): 209-212.
11 Zheng C H, Wang L, Zhang Y X, et al. Partitioning of hazardous trace elements among air pollution control devices in ultra-low-emission coal-fired power plants[J]. Energy & Fuels, 2017, 31(6): 6334-6344.
12 赵志锋, 杜谦, 董鹤鸣, 等[J]. 湿法脱硫装置对燃煤锅炉PM2.5排放特征的影响[J]. 化工学报, 2017, 68(11): 4261-4271.
Zhao Z F, Du Q, Dong H M, et al. Influence of wet flue gas desulfurization devices on PM2.5 emission characteristics of coal-fired boilers[J]. CIESC Journal, 2017, 68(11): 4261-4271.
13 徐文东, 曾荣树, 叶大年, 等. 电厂煤燃烧后元素硒的分布及对环境的贡献[J]. 环境科学, 2005, 26(2): 64-68.
Xu W D, Zeng R S, Ye D N, et al. Distributions and environmental impacts of selenium in wastes of coal from a power plant[J]. Environmental Science, 2005, 26(2): 64-68.
14 López-Antón M A, Díaz-Somoano M, Spears D A, et al. Arsenic and selenium capture by fly ashes at low temperature[J]. Environmental Science & Technology, 2006, 40(12): 3947-3951.
15 Fu B, Liu G J, Sun M, et al. Emission and transformation behavior of minerals and hazardous trace elements (HTEs) during coal combustion in a circulating fluidized bed boiler[J]. Environmental Pollution, 2018, 242: 1950-1960.
16 陈冠益, 王钦, 颜蓓蓓. 煤中痕量元素在循环流化床锅炉中的迁移行为与富集特性[J]. 燃料化学学报, 2013, 41(9): 1050-1055.
Chen G Y, Wang Q, Yan B B. Mobility and enrichment of trace elements in a coal-fired circulating fluidized bed boiler[J]. Journal of Fuel Chemistry and Technology, 2013, 41(9): 1050-1055.
17 Seames W S, Wendt J O L. Regimes of association of arsenic and selenium during pulverized coal combustion[J]. Proceedings of the Combustion Institute, 2007, 31(2): 2839-2846.
18 王珲, 宋蔷, 姚强, 等. ICP-OES/ICP-MS测定煤中多种元素的微波消解方法研究[J]. 光谱学与光谱分析, 2012, 32(6): 1662-1665.
Wang H, Song Q, Yao Q, et al. Study on microwave digestion of coal for the determination of multi-element by ICP-OES and ICP-MS[J]. Spectroscopy and Spectral Analysis, 2012, 32(6): 1662-1665.
19 张锴, 刘轩, 苏银皎, 等. 一种测定燃煤电厂煤及其燃烧副产物中砷、硒、铅的方法: 110487758B[P]. 2021-05-14.
Zhang K, Liu X, Su Y J, et al. Method for determining arsenic, selenium and lead in coal-fired power plant coals and combustion byproducts thereof: 110487758B[P]. 2021-05-14.
20 Contreras M L, García-Frutos F J, Bahillo A. Oxy-fuel combustion effects on trace metals behaviour by equilibrium calculations[J]. Fuel, 2013, 108: 474-483.
21 韩军, 梁洋硕, 赵波, 等. 混煤燃烧过程中砷/硒与飞灰中矿物质之间的高温原位反应[J]. 燃料化学学报, 2020, 48(11): 1356-1364.
Han J, Liang Y S, Zhao B, et al. In-situ reaction between arsenic/selenium and minerals in fly ash at high temperature during blended coal combustion[J]. Journal of Fuel Chemistry and Technology, 2020, 48(11): 1356-1364.
22 Querol X, Fernández-Turiel J L, López -Soler A. Trace elements in coal and their behaviour during combustion in a large power station[J]. Fuel, 1995, 74(3): 331-343.
23 Ma T T, Huang Y D, Deng S, et al. The relationship between selenium retention and fine particles removal during coal combustion[J]. Fuel, 2020, 265: 116859.
24 Shen F H, Liu J, Zhang Z, et al. Temporal measurements and kinetics of selenium release during coal combustion and gasification in a fluidized bed[J]. Journal of Hazardous Materials, 2016, 310: 40-47.
25 邢佳颖, 王春波, 张月, 等. Se和SeO2在O2/CaO(001)表面吸附反应的第一性原理研究[J]. 燃料化学学报, 2019, 47(8): 993-999.
Xing J Y, Wang C B, Zhang Y, et al. First-principles study of the adsorption and reaction of Se and SeO2 on O2/CaO(001) surface[J]. Journal of Fuel Chemistry and Technology, 2019, 47(8): 993-999.
26 Liu Z, Han J, Zhao L, et al. Effects of Se and SeO2 on the denitrification performance of V2O5-WO3/TiO2 SCR catalyst[J]. Applied Catalysis A: General, 2019, 587: 117263.
27 Shin Y, Lee D W, Choi K Y, et al. VSb(SeO3)4, first selenite containing V3+ cation: synthesis, structure, characterization, magnetic properties, and calculations[J]. Inorganic Chemistry, 2013, 52(24): 14224-14230.
28 Wang L, Zheng C H, Zhang Y X, et al. Speciation characteristics and mobility of trace elements across ultralow emission air pollution control devices[J]. Energy & Fuels, 2017, 31(12): 13963-13971.
29 刘福国. 煤粉炉燃烧效率工程预测模型[J]. 动力工程, 2004, 24(5): 636-639.
Liu F G. Engineering forecasting model of combustion efficiency for pulverized fired boiler[J]. Journal of Chinese Society of Power Engineering, 2004, 24(5): 636-639.
30 刘建忠, 张光学, 周俊虎, 等. 燃煤细灰的形成及微观形态特征[J]. 化工学报, 2006, 57(12): 2976-2980.
Liu J Z, Zhang G X, Zhou J H, et al. Formation and micromorphology characteristics of fine particles generated during coal combustion[J]. Journal of Chemical Industry and Engineering (China), 2006, 57(12): 2976-2980.
31 徐飞, 骆仲泱, 王鹏, 等. 不同工况和粒径下飞灰孔隙结构的实验研究[J]. 动力工程, 2007, 27(4): 620-624.
Xu F, Luo Z Y, Wang P, et al. Experimental study on the porous structure of variously sized fly ash particles under different combustion conditions[J]. Journal of Chinese society of Power Engineering, 2007, 27(4): 620-624.
32 Barrett E P, Joyner L G, Halenda P P. The determination of pore volume and area distributions in porous substances(I): Computations from nitrogen isotherms[J]. Journal of the American Chemical Society, 1951, 73(1): 373-380.
33 Sing K S W. Reporting physisorption data for gas/solid systems with special reference to the determination of surface area and porosity (Recommendations 1984)[J]. Pure and Applied Chemistry, 1985, 57(4): 603-619.
[1] 黄丽菁, 黄继娇, 李鹏辉, 刘芷诺, 蒋康杰, 吴文娟. 木质素羟丙基磺甲基化改性及其对纤维素酶水解的影响[J]. 化工学报, 2022, 73(7): 3232-3239.
[2] 赵继昊, 唐伟强, 徐小飞, 赵双良, 贺炅皓. 高分子复合材料中键合剂在不同纳米填料表面的吸附能计算[J]. 化工学报, 2022, 73(7): 3174-3181.
[3] 黄陆月, 刘畅, 许勇毅, 邢浩若, 王峰, 马双忱. CDI二维浓度传质模型的建立以及实验验证[J]. 化工学报, 2022, 73(7): 2933-2943.
[4] 朱江伟, 马鹏飞, 杜晓, 杨言言, 郝晓刚, 罗善霞. 基于可变价NiFe-LDH/rGO对磷酸根离子的特异性电控分离[J]. 化工学报, 2022, 73(7): 3057-3067.
[5] 李智超, 郑瑜, 张润楠, 姜忠义. 高通量抗污染氧化石墨烯膜研究进展[J]. 化工学报, 2022, 73(6): 2370-2380.
[6] 李丽媛, 王建强, 陈奕, 郭友娣, 周健, 刘志成, 王仰东, 谢在库. 甲醇制丙烯反应中ZSM-5分子筛催化剂积炭失活介尺度机制研究[J]. 化工学报, 2022, 73(6): 2669-2676.
[7] 何聪, 钟文琪, 周冠文, 陈曦. 高海拔地区水泥生料悬浮炉分解特性研究[J]. 化工学报, 2022, 73(5): 2120-2129.
[8] 李雪, 东明, 张璜, 谢俊. 潮湿环境下微尺度颗粒撞击平板的动力学研究[J]. 化工学报, 2022, 73(5): 1940-1946.
[9] 孙敏, 贾辉, 秦卿雯, 王琦, 郭子楠, 罗艳茹, 王捷. 电阻抗成像原位在线监测超滤膜污染行为研究[J]. 化工学报, 2022, 73(4): 1754-1762.
[10] 刘碧强, 曹海山. 基于流量校准的吸附测量方法及误差分析[J]. 化工学报, 2022, 73(4): 1597-1605.
[11] 张逸伟, 唐海荣, 何勇, 朱燕群, 王智化. 臭氧低温氧化烟气脱硝过程中的氮平衡试验研究[J]. 化工学报, 2022, 73(4): 1732-1742.
[12] 王毅, 熊启钊, 陈杨, 杨江峰, 李立博, 李晋平. 锆基金属有机骨架材料用于氨吸附性能的研究[J]. 化工学报, 2022, 73(4): 1772-1780.
[13] 张浩, 赵宇, 徐志明, 李晋辉. 羧甲基葡聚糖的快速沉降法阻垢特性研究[J]. 化工学报, 2022, 73(4): 1515-1522.
[14] 王祺, 房阔, 贺聪慧, 王凯军. 流动电极电容去离子技术综述：研究进展与未来挑战[J]. 化工学报, 2022, 73(3): 975-989.
[15] 钟国栋, 邓超和, 王洋, 王佳韵, 王如竹. 蜂窝状水凝胶吸附床传热传质特性数值模拟及验证[J]. 化工学报, 2022, 73(3): 1083-1092.
Viewed
Full text


Abstract

Cited
  Shared   
  Discussed   
No Suggested Reading articles found!
版权所有 © 2019 《化工学报》编辑部
北京市东城区青年湖南街13号（100011）
电话：010-64519489，010-64519362，010-64519485，010-64519490，010-64519451
E-Mail：hgxb@cip.com.cn
京ICP备12046843号-7
京公网安备 11010102001995号
本系统由北京玛格泰克科技发展有限公司设计开发