高碱煤与煤矸石掺烧SO2和NO减排及结渣抑制研究

doi:10.11949/0438-1157.20221221

化工学报 ›› 2022, Vol. 73 ›› Issue (12): 5581-5591.DOI: 10.11949/0438-1157.20221221

高碱煤与煤矸石掺烧SO₂和NO减排及结渣抑制研究

黄顺进¹(), 张丽¹^,², 颜井冲¹(), 王志刚³, 雷智平¹, 李占库¹, 任世彪¹, 王知彩¹, 水恒福¹

^1.安徽工业大学化学与化工学院，安徽马鞍山 243002
^2.安徽工业大学计算机科学与技术学院，安徽马鞍山 243002
^3.德州学院化学与化学工程学院，山东德州 253023

收稿日期:2022-09-07 修回日期:2022-11-09 出版日期:2022-12-05 发布日期:2023-01-17
通讯作者: 颜井冲
作者简介:黄顺进（1998—），男，硕士研究生，hsj18756014188@163.com
基金资助:
国家自然科学基金项目(22178001);安徽省优秀青年科研项目(2022AH030045);安徽省高校优秀青年人才支持项目(gxyqZD2022029)

Investigation on cofiring high-alkali coal with coal gangues: SO₂, NO reduction and ash slagging inhibition

Shunjin HUANG¹(), Li ZHANG¹^,², Jingchong YAN¹(), Zhigang WANG³, Zhiping LEI¹, Zhanku LI¹, Shibiao REN¹, Zhicai WANG¹, Hengfu SHUI¹

^1.School of Chemistry & Chemical Engineering, Anhui University of Technology, Ma’anshan 243002, Anhui, China
^2.School of Computer Science and Technology, Anhui University of Technology, Ma’anshan 243002, Anhui, China
^3.College of Chemistry and Chemical Engineering, Dezhou University, Dezhou 253023, Shandong, China

Received:2022-09-07 Revised:2022-11-09 Online:2022-12-05 Published:2023-01-17
Contact: Jingchong YAN

摘要/Abstract

摘要：

结渣和沾污是高碱煤燃烧锅炉中普遍存在的难题。同时，源于采煤和洗煤的大量固废煤矸石出于经济和生态考虑亦须实现减量化处理和资源化利用。基于此，通过掺烧高碱煤与煤矸石抑制煤灰沾污和结渣发生以及实现煤矸石的资源化利用，同时考察掺烧过程中污染气体(SO₂和NO)的释放及减排行为。结果表明，高碱煤与煤矸石静态的掺烧反应服从三维扩散模型，在一定比例下掺烧反应活化能低于单一燃料燃烧的活化能。掺烧过程中焦炭和CO可还原NO，同时灰分中过渡金属组分可促进NO原位减排，而SO₂的减排效果很大程度上取决于两燃料的掺烧比例及其灰分组成。掺烧过程中碱金属有效固留于灰渣中，从而降低煤灰沾污和结渣倾向，而碱土金属(Ca，Mg等)可同时与灰分组成中的硅铝及气相中SO₂发生竞争反应。此外，通过改变掺烧煤矸石矿物组成可调节灰渣组成及熔融温度。本研究结果可为通过掺烧高碱煤与煤矸石来缓解锅炉沾污和结渣难题提供科学参考。

关键词: 结渣和沾污, 高碱煤, 煤矸石, SO₂和NO减排, 灰熔融温度

Abstract:

Slagging and fouling are common problems in high-alkali coal-fired boilers. Meanwhile, a large amount of solid waste coal gangue from coal mining and coal washing needs to be reduced and utilized for economical and ecological considerations. Given this, cofiring high-alkali coal (HAC) with coal gangues (CG) was performed to verify the possibility of inhibiting ash-related problems of HAC meanwhile achieving resource utilization of CG. Besides, the evolution behaviors of pollution gases (SO₂ and NO) were examined. The results show that cofiring reaction follows a three dimensional diffusion model, and at proper ratios the activation energy of cofiring can be lower than that of mono-combustion. NO can be efficiently reduced during cofiring with the enhanced catalytic components in the blended fuels, while the reduction of SO₂ is largely determined by the blending ratio and ash compositions. Alkali metals are effectively retained in ashes thus lowering the fouling and slagging propensity, while alkaline metals participate the competitive reaction with silica and alumina components and that of SO₂ fixation reactions. The ash fusion temperatures can be adjusted through cofiring with CG with various inherent minerals, thus providing the opportunity to alleviate the ash-related problems for burning HAC in commercial boilers.

Key words: slagging and fouling, high-alkali coal, coal gangues, SO₂ and NO reduction, ash fusion temperatures

中图分类号:

TQ 53

黄顺进, 张丽, 颜井冲, 王志刚, 雷智平, 李占库, 任世彪, 王知彩, 水恒福. 高碱煤与煤矸石掺烧SO₂和NO减排及结渣抑制研究[J]. 化工学报, 2022, 73(12): 5581-5591.

Shunjin HUANG, Li ZHANG, Jingchong YAN, Zhigang WANG, Zhiping LEI, Zhanku LI, Shibiao REN, Zhicai WANG, Hengfu SHUI. Investigation on cofiring high-alkali coal with coal gangues: SO₂, NO reduction and ash slagging inhibition[J]. CIESC Journal, 2022, 73(12): 5581-5591.

图/表 14

表1 HM、XJG和ATB的工业分析和元素分析

Table 1 Proximate and ultimate analyses of HM， XJG and ATB

样品	工业分析/%(质量，ad)				元素分析/%(质量，daf)
样品	M	Ash	VM	FC	C	H	O^①	N
HM	16	5.4	40.8	37.8	76.87	6.01	15.65	1.12
ATB	1.3	59.0	21.1	18.6	80.49	3.55	13.34	0.81
XJG	1.9	66.9	10.6	20.6	79.77	3.64	14.14	1.09

图1 HM与XJG掺烧TG曲线（a）和DTG曲线（b）

Fig.1 TG (a) and DTG (b) curves of HM cofiring with XJG

图2 燃烧特性参数

Fig.2 Characteristic parameters of combustion

图3 3D扩散（圆柱对称）模型对掺烧曲线进行数学拟合

Fig.3 Mathematical fitting cofiring curves with 3D diffusion (cylinder symmetry)

图4 活化能随CG掺烧比的变化

Fig.4 Variations of activation energy with cofiring ratios of CG

表2 灰渣的化学成分

Table 2 Chemical compositions of the ashes

样品	化学组成/%(质量)
样品	SiO₂	Al₂O₃	Na₂O	K₂O	CaO	MgO	Fe₂O₃	P₂O₅	TiO₂	SO₃	Others
100HM	40.07	19.97	3.20	0.95	13.89	4.63	14.24	1.04	1.25	0.03	0.73
90HM10XJG	42.92	19.13	3.35	1.16	12.36	3.97	14.26	0.80	1.21	0.03	0.80
80HM20XJG	43.93	18.94	3.35	1.28	11.82	3.81	14.04	0.79	1.21	0.04	0.79
60HM40XJG	46.91	18.01	3.58	1.45	10.53	3.10	14.01	0.52	1.17	0.03	0.69
100XJG	50.75	17.07	3.56	1.69	9.03	2.38	13.48	0.26	1.08	0.04	0.66
90HM10ATB	40.22	21.07	2.37	0.88	14.45	3.48	13.85	0.78	1.41	0.77	0.73
80HM20ATB	40.14	21.78	1.81	0.82	14.72	2.78	13.21	0.64	1.53	1.87	0.70
60HM40ATB	40.23	22.92	1.09	0.74	14.61	1.94	12.41	0.48	1.67	3.29	0.62
100ATB	42.07	25.44	0.10	0.68	12.69	0.43	10.82	0.21	1.83	5.22	0.51

图5 掺烧过程中SO2和NO的释放曲线

Fig.5 Evolution curves of SO2 and NO during cofiring

表3 样品硫形态分析

Table 3 Sulfur form analysis of the samples

样品	形态硫/%(ad)
样品	全硫S_t	硫酸盐硫S_s	硫化铁硫S_p	有机硫S_o
HM	0.215	0.009	0.024	0.182
XJG	0.475	0.078	0.382	0.015
ATB	3.675	0.872	2.786	0.018

图6 掺烧过程SO2和NO理论与实验释放量的比较

Fig.6 Comparison of theoretical and experimental SO2 and NO evolution

图7 灰渣的XRD谱图

Fig.7 XRD patterns of the ashes

图8 掺烧比例对灰渣组成的影响

Fig.8 Effect of cofiring ratio on ash compositions

图9 掺烧灰渣的沾污和结渣趋势

Fig.9 Fouling and slagging tendency of the ashes

表4 各评判指标的边界条件［27-28］

Table 4 Judgement boundaries for various indexes［27-28］

判别指数	边界条件
判别指数	轻度	中度	重度
$S R$	>72	65~72	<65
$R b / a$	<0.206	0.206~0.4	>0.4
$R S$	<0.6	0.6~2.0	>2.0
$F u$	<0.6	0.6~40	>40
$H m$	<10% 轻微结渣	10%~20% 中度结渣	>20% 严重结渣

表4 各评判指标的边界条件［27-28］

Table 4 Judgement boundaries for various indexes［27-28］

判别指数	边界条件
判别指数	轻度	中度	重度
$S R$	>72	65~72	<65
$R b / a$	<0.206	0.206~0.4	>0.4
$R S$	<0.6	0.6~2.0	>2.0
$F u$	<0.6	0.6~40	>40
$H m$	<10% 轻微结渣	10%~20% 中度结渣	>20% 严重结渣

图10 掺烧灰渣的熔融温度

Fig.10 Ash melting temperatures of the cofiring ashes

参考文献 34

1	Zhou J B, Zhuang X G, Alastuey A, et al. Geochemistry and mineralogy of coal in the recently explored Zhundong large coal field in the Junggar basin, Xinjiang province, China[J]. International Journal of Coal Geology, 2010, 82(1): 51-67.
2	Li X, Li J, Wu G G, et al. Clean and efficient utilization of sodium-rich Zhundong coals in China: behaviors of sodium species during thermal conversion processes[J]. Fuel, 2018, 218: 162-173.
3	Liu Y Z, He Y, Wang Z H, et al. Characteristics of alkali species release from a burning coal/biomass blend[J]. Applied Energy, 2018, 215: 523-531.
4	Shi H, Wu Y X, Zhang M, et al. Ash deposition of Zhundong coal in a 350 MW pulverized coal furnace: influence of sulfation[J]. Fuel, 2020, 260: 116317.
5	Wu X J, Zhang X, Yan K, et al. Ash deposition and slagging behavior of Chinese Xinjiang high-alkali coal in 3 MW_th pilot-scale combustion test[J]. Fuel, 2016, 181: 1191-1202.
6	Yang T, Wang X B, Li W G, et al. The layered structure of ash deposition in a 350 MW PC furnace burning high sodium-calcium lignite[C]//Clean Coal Technology and Sustainable Development. Singapore, 2016: 81-85.
7	Yang Y P, Lin X C, Chen X J, et al. Investigation on the effects of different forms of sodium, chlorine and sulphur and various pretreatment methods on the deposition characteristics of Na species during pyrolysis of a Na-rich coal[J]. Fuel, 2018, 234: 872-885.
8	Zygarlicke C J, Stomberg A L, Folkedahl B C, et al. Alkali influences on sulfur capture for North Dakota lignite combustion[J]. Fuel Processing Technology, 2006, 87(10): 855-861.
9	Wang X B, Xu Z X, Wei B, et al. The ash deposition mechanism in boilers burning Zhundong coal with high contents of sodium and calcium: a study from ash evaporating to condensing[J]. Applied Thermal Engineering, 2015, 80: 150-159.
10	Wang Y Z, Jin J, Liu D Y, et al. Understanding ash deposition for Zhundong coal combustion in 330 MW utility boiler: focusing on surface temperature effects[J]. Fuel, 2018, 216: 697-706.
11	Song G L, Yang S B, Song W J, et al. Release and transformation behaviors of sodium during combustion of high alkali residual carbon[J]. Applied Thermal Engineering, 2017, 122: 285-296.
12	Wei B, Wang X B, Tan H Z, et al. Effect of silicon-aluminum additives on ash fusion and ash mineral conversion of Xinjiang high-sodium coal[J]. Fuel, 2016, 181: 1224-1229.
13	Wang Y Z, Jin J, Liu D Y, et al. Understanding ash deposition for the combustion of Zhundong coal: focusing on different additives effects[J]. Energy & Fuels, 2018, 32(6): 7103-7111.
14	Yang H R, Jin J, Liu D Y, et al. The influence of vermiculite on the ash deposition formation process of Zhundong coal[J]. Fuel, 2018, 230: 89-97.
15	Yu Z H, Jin J, Hou F X, et al. Understanding effect of phosphorus-based additive on ash deposition characteristics during high-sodium and high-calcium Zhundong coal combustion in drop-tube furnace[J]. Fuel, 2021, 287: 119462.
16	Liang Y C, Liang H D, Zhu S Q. Mercury emission from spontaneously ignited coal gangue hill in Wuda coalfield, Inner Mongolia, China[J]. Fuel, 2016, 182: 525-530.
17	Caneda-Martínez L, Sánchez J, Medina C, et al. Reuse of coal mining waste to lengthen the service life of cementitious matrices[J]. Cement and Concrete Composites, 2019, 99: 72-79.
18	Ma H Q, Zhu H G, Wu C, et al. Study on compressive strength and durability of alkali-activated coal gangue-slag concrete and its mechanism[J]. Powder Technology, 2020, 368: 112-124.
19	Wu Y G, Yu X Y, Hu S Y, et al. Experimental study of the effects of stacking modes on the spontaneous combustion of coal gangue[J]. Process Safety and Environmental Protection, 2019, 123: 39-47.
20	Zhou X, Zhang T, Wan S, et al. Immobilizatiaon of heavy metals in municipal solid waste incineration fly ash with red mud-coal gangue[J]. Journal of Material Cycles and Waste Management, 2020, 22(6): 1953-1964.
21	Pallarés J, Herce C, Bartolomé C, et al. Investigation on co-firing of coal mine waste residues in pulverized coal combustion systems[J]. Energy, 2017, 140: 58-68.
22	Zhang Y Y, Zhang Z Z, Zhu M M, et al. Interactions of coal gangue and pine sawdust during combustion of their blends studied using differential thermogravimetric analysis[J]. Bioresoure Technology, 2016, 214: 396-403.
23	Zhang Y Y, Zhao J T, Ma Z B, et al. Effect of oxygen concentration on oxy-fuel combustion characteristic and interactions of coal gangue and pine sawdust[J]. Waste Management, 2019, 87: 288-294.
24	Ma B G, Li X G, Xu L, et al. Investigation on catalyzed combustion of high ash coal by thermogravimetric analysis[J]. Thermochimica Acta, 2006, 445(1): 19-22.
25	Niu S L, Han K H, Lu C M. Characteristic of coal combustion in oxygen/carbon dioxide atmosphere and nitric oxide release during this process[J]. Energy Conversion and Management, 2011, 52(1): 532-537.
26	Bagchi T P, Sen P K. Combined differential and integral method for analysis of non-isothermal kinetic data[J]. Thermochimica Acta, 1981, 51(2/3): 175-189.
27	Deng S H, Tan H Z, Wei B, et al. Investigation on combustion performance and ash fusion characteristics of Zhundong coal co-combustion with coal gangue[J]. Fuel, 2021, 294: 120555.
28	Pronobis M. Evaluation of the influence of biomass co-combustion on boiler furnace slagging by means of fusibility correlations[J]. Biomass and Bioenergy, 2005, 28(4): 375-383.
29	Wang L, Skjevrak G, Hustad J E, et al. Sintering characteristics of sewage sludge ashes at elevated temperatures[J]. Fuel Processing Technology, 2012, 96: 88-97.
30	Shi M Z, Zhang R, Zhang L J, et al. Effects of alkali and alkaline earth metal species on the combustion characteristics and synergistic effects: sewage sludge and its blend with coal[J]. Waste Management, 2022, 146: 119-129.
31	Lei Z P, Liu M C, Yan J C, et al. Catalytic combustion of coke nuts and in-situ NO reduction under the action of steel scale[J]. Fuel, 2021, 289:119779.
32	Zhang L, Yan J C, Lei Z P, et al. Steel scale-CaO composite catalyst for coke combustion and in-situ NO and SO₂ removal[J]. Journal of Industrial and Engineering Chemistry, 2022, 110: 375-381.
33	Si J P, Liu X W, Xu M H, et al. Effect of kaolin additive on PM_2.5 reduction during pulverized coal combustion: importance of sodium and its occurrence in coal[J]. Applied Energy, 2014, 114: 434-444.
34	Yu K J, Chen X P, Cai T Y, et al. The effect of Kaolinite's structure on migration and release characteristics of sodium under oxy-fuel combustion condition[J]. Fuel, 2020, 277: 118154.

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高碱煤与煤矸石掺烧SO₂和NO减排及结渣抑制研究

Investigation on cofiring high-alkali coal with coal gangues: SO₂, NO reduction and ash slagging inhibition

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