Physicochemical properties and electromagnetic wave absorption performance ofcoal gasification fine ash
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摘要: 煤气化技术作为煤炭清洁利用的主要途径之一在中国得到快速发展，细灰是煤气化过程中不可避免产生的新型固体废物。国家对绿色、清洁生产和发展循环经济逐步推行，细灰的资源化利用和无害化处理技术成为实现煤气化技术环保效益和经济效益兼得的关键所在。以煤气化细灰为研究对象，对细灰进行干燥、球磨预处理得到中位径为2 μm的样品，利用XRD、Raman、SEM、TEM和XPS等分析测试技术对其晶体结构、微观形貌、组成、分子构造和元素化学态进行表征，并测试了细灰电磁波吸收性能。结果表明：细灰中含有部分石墨化的碳和单质铁，具有较完整的孔隙结构，这为其作为电磁波吸收材料提供了可能性；细灰/石蜡吸波剂在较薄厚度下同时表现出较宽的有效吸收带宽和一定强度的反射损耗，当匹配厚度为1.7 mm时，该吸波剂在15.6 GHz时达到最小反射损耗值，为−17.6 dB，此时有效吸收带宽(反射损耗值≤−10 dB)达到4.2 GHz。此外，雷达散射截面模拟结果表明：该吸波涂层能有效降低完美导体基板的电磁波散射。Abstract: Coal gasification technology, one of the main ways to clean utilization of coal, has been developed rapidly in China. Coal gasification fine ash is a new type of solid waste inevitably produced in the process of coal gasification. With the implementation of green and clean production and the development of a circular economy, the resource utilization and harmless treatment technology of coal gasification fine ash have become the key to achieving both the environmental and economic benefits of coal gasification technology. Taking coal gasification fine ash as the research object, the samples with a median diameter of 2 μm were prepared by drying and ball milling. The physicochemical properties of the pre-treated coal gasification fine ash were characterized by XRD, Raman, SEM, TEM, and XPS, and the crystal structure, micromorphology, composition, molecular structure, and chemical state of the elements of the coal gasification fine ash were analyzed. Moreover, the electromagnetic wave absorption performance was tested. The results show that the fine ash contains some graphitized carbon and zero-valent iron, and has a relatively complete pore structure, which provides a possibility for it to be used as an electromagnetic wave-absorbing material. The absorbers exhibit the minimum reflection loss (RLmin) of −17.6 dB at 1.7 mm, and broad absorption bandwidth (RL≤−10 dB) of 4.2 GHz. In addition, the radar cross-section simulation results show that the fine ash/paraffin coating can effectively reduce the electromagnetic wave scattering of the perfect conductor substrate.
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图 3 细灰的XRD图谱(a)和拉曼图谱(b)
${I_{{{\rm{D}}_{\rm{1}}}{\rm{ + }}{{\rm{D}}_{\rm{2}}}{\rm{ + }}{{\rm{D}}_{\rm{3}}}{\rm{ + }}{{\rm{D}}_{\rm{4}}}}} $/IG—The ratio of D1, D2, D3 and D4 peak intensity to the intensity of G peak;${A_{{{\rm{D}}_{\rm{1}}}{\rm{ + }}{{\rm{D}}_{\rm{2}}}{\rm{ + }}{{\rm{D}}_{\rm{3}}}{\rm{ + }}{{\rm{D}}_{\rm{4}}}}} $/AG—The ratio of D1, D2, D3, D4 peak area and G peak area
Figure 3. XRD pattern (a) and Raman spectrum (b) of fine ash
图 5 细灰的吸附/脱附等温线(a)、孔径分布(b)、孔表面积分布(c)和孔体积分布(d)
dV/dlgW—Aperture distribution
Figure 5. Adsorption/desorption isotherm (a), pore size distribution (b), pore surface area distribution (c) and pore volume distribution (d) of fine ash
图 6 细灰的SEM图像((a)~(c))、TEM图像((d)~(g))和选区(h)的元素分布图(i)
Figure 6. SEM images ((a)-(c)), TEM images ((d)-(g)) and element distribution (i) of selection (h) of fine ash
图 7 细灰的SEM图像(a)、选区的EDX元素分布图像((b)~(f))和区域1 (g)、区域2 (h)、区域3 (i)的元素含量图
Figure 7. SEM image (a) of fine ash, EDX element distribution images ((b)-(f)) of selected area and regional element content map of region 1 (g), region 2 (h) and region 3 (i)
图 8 细灰的XPS图谱：(a)全谱图；(b) Fe2p；(c) O1s；(d) C1s；(e) Si2p；(f) Al2p
Figure 8. XPS spectra of fine ash: (a) Full spectrum; (b) Fe2p; (c) O1s; (d) C1s; (e) Si2p; (f) Al2p
图 10 细灰的磁滞回线：(a)饱和磁化强度；(b)矫顽力
M—Magnetization intensity
Figure 10. Hysteresis curve of fine ash: (a) Saturation magnetization; (b) Coercivity
图 11 细灰/石蜡(FA/PF)吸波剂的反射损耗图
d—Thickness; RL—Reflection loss
Figure 11. Reflection loss of fine ash/paraffin absorber (FA/PF)
图 12 FA/PF吸波剂的相对复介电常数的实部ε′ (a)和虚部ε'' (b)、介电损耗角正切tanδε (c)、相对复磁导率的实部μ′ (d)和虚部μ'' (e)及磁损耗角正切tanδµ (f)
Figure 12. Real part ε′ (a) and imaginary part ε'' (b) of complex permittivity, tangent of dielectric loss tanδε (c), real part μ′ (d) and imaginary part μ'' (e) of complex permeability and tangent of magnetic loss tanδµ (f) of FA/PF absorbers
图 13 40wt%FA/PF吸波剂的反射损耗RL、厚度tm和阻抗模值|Zin/Z0|与频率ƒ的关系曲线
$t_{\rm{m}}^{{\rm{exp}}} $—Thickness of absorbing agent obtained by experiment; $t_{\rm{m}}^{{\rm{sim}}} $—Thickness of absorbing agent obtained by simulation
Figure 13. Relationship between reflection loss RL, thickness tm, impedance modulus |Zin/Z0| and frequency f of 40wt%FA/PF absorber
图 14 完美导体基板(PEC)和具有FA/PF吸波涂层的完美导体基板的雷达散射截面模拟对比
RCS—Radar cross-section
Figure 14. Comparison of Radar cross-section simulation of perfectly conducting substrate (PEC) and perfectly conducting substrate with FA/PF absorbing coating
表 1 细灰(FA)的工业分析及元素分析
Table 1. Proximate and ultimate analysis of fine ash (FA)
Sample Proximate analysis/wt% Ultimate analysis/wt% Ad Vd FCd Cd Hd O*d Nd St, d FA 32.59 1.07 66.34 66.73 0.16 0.24 0.09 0.19 Notes: d—Dry basis; A—Ash content; V—Volatile matter content; FC—Fixed carbon content; St—Total sulfur content; *—By difference. 
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表 2 FA浸出毒性测试结果
Table 2. Leaching toxicity test results of FA
Sample Cr(VI)/(mg·L–1) As/(μg·L–1) Hg/(μg·L–1) Ni/(μg·L–1) Cu/(μg·L–1) Zn/(μg·L–1) Cd/(μg·L–1) Pb/(μg·L–1) FA ND 0.32 0.27 0.06 0.08 2.29 ND ND Lower limit of detectability 0.004 0.10 0.02 0.02 0.01 — 0.01 0.03 Note: ND—The instrument test line was not reached.
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表 3 浸出毒性鉴别标准值
Table 3. Standard values for identification of leaching toxicity
Component Limited value of concentration/(mg·L–1) Cr(VI) 5 As 5 Hg 0.1 Ni 5 Cu 100 Zn 100 Cd 1 Pb 5
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表 4 煤基固废吸波剂的微波吸收性能
Table 4. Microwave absorption properties of coal-based solid waste absorber
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[1] GRABNER M, MEYER B. Performance and exergy analysis of the current developments in coal gasification technology[J]. Fuel, 2014, 116: 910-920. doi: 10.1016/j.fuel.2013.02.045 [2] GUO Q, LI S, GONG Y, et al. Application of qualitative trend analysis in fault diagnosis of entrained-flow coal-water slurry gasifier[J]. Control Engineering Practice, 2021, 112: 104835. doi: 10.1016/j.conengprac.2021.104835 [3] LI W, YU Z, GUAN G. Catalytic coal gasification for methane production: A review[J]. Carbon Resources Conversion, 2021, 4: 89-99. doi: 10.1016/j.crcon.2021.02.001 [4] 王利峰. 我国煤气化技术发展与展望[J]. 洁净煤技术, 2022, 28(2): 115-121.WANG Lifeng. Development and prospect of coal gasification technology in China[J]. Clean Coal Technology, 2022, 28(2): 115-121(in Chinese). [5] 程晓磊, 张鑫. 现代煤气化技术现状及发展趋势综述[J]. 煤质技术, 2021, 36(1): 1-9.CHENG Xiaolei, ZHANG Xin. Summary of present situation and development trend of modern coal gasification technology[J]. Coal Quality Technology, 2021, 36(1): 1-9(in Chinese). [6] KIKUCHI K, SUZUKI A, MOCHIZUKI T, et al. Ash-agglomerating gasification of coal in a spouted bed reactor[J]. Fuel, 1985, 64(3): 368-372. doi: 10.1016/0016-2361(85)90426-0 [7] 周安宁, 高影, 李振, 等. 煤气化灰渣组成结构及分选加工研究进展[J]. 西安科技大学学报, 2021, 41(4): 575-584.ZHOU Anning, GAO Ying, LI Zhen, et al. Composition structure and separation processing of ash and slag during coal gasification[J]. Journal of Xi'an University of Science and Technology, 2021, 41(4): 575-584(in Chinese). [8] 胡小波, 杨晓勤, 莫文龙, 等. 循环流化床煤气化炉灰渣的组成结构特征与热转化性能[J]. 燃料化学学报, 2022, 50(10): 1361-1370. doi: 10.1016/S1872-5813(22)60024-0HU Xiaobo, YANG Xiaoqin, MO Wenlong, et al. Structural characteristics and thermal conversion performance of ash and slag from circulating fluidized bed gasifier[J]. Journal of Fuel Chemistry and Technology, 2022, 50(10): 1361-1370(in Chinese). doi: 10.1016/S1872-5813(22)60024-0 [9] LIU X D, JIN Z W, JING Y H, et al. Review of the characteristics and graded utilisation of coal gasification slag[J]. Chinese Journal of Chemical Engineering, 2021, 35: 92-106. doi: 10.1016/j.cjche.2021.05.007 [10] XU J, YANG Y, LI Y W. Recent development in converting coal to clean fuels in China[J]. Fuel, 2015, 152: 122-130. doi: 10.1016/j.fuel.2014.11.059 [11] GAI H J, FENG Y R, LIN K Q, et al. Heat integration of phenols and ammonia recovery process for the treatment of coal gasification wastewater[J]. Chemical Engineering Journal, 2017, 327: 1093-1101. doi: 10.1016/j.cej.2017.06.033 [12] ZHANG X S, SONG X D, SU W G, et al. In-situ study on gasification reaction characteristics of Ningdong coal chars with CO2[J]. Journal of Fuel Chemistry and Technology, 2019, 47(4): 385-392. doi: 10.1016/S1872-5813(19)30018-0 [13] 刘艳芳, 崔龙鹏, 郎子轩, 等. Shell粉煤气化灰渣环境风险评价[J]. 石油学报(石油加工), 2022, 38(1): 137-145.LIU Yanfang, CUI Longpeng, LANG Zixuan, et al. Environmental risk assessment of ash and slag from shell pulverized coal gasification[J]. Acta Petrolei Sinica (Petroleum Processing Section), 2022, 38(1): 137-145(in Chinese). [14] 王文钰, 李伟, 梁晨, 等. 西北地区气流床煤气化细灰理化特性研究[J]. 洁净煤技术, 2021, 27(3): 94-100.WANG Wenyu, LI Wei, LIANG Chen, et al. Research on physicochemical characteristics of fine slag from gasification in Northwest China[J]. Clean Coal Technology, 2021, 27(3): 94-100 (in Chinese). [15] GAO Y, ZHOU A N, ZHAO W, et al. Study on the property and airflow grading of Ningxia coal gasification fine slag[J]. Cleaner Chemical Engineering, 2022, 4: 100068. doi: 10.1016/j.clce.2022.100068 [16] WU R F, LYU P, WANG J F, et al. Catalytic upgrading of cow manure pyrolysis vapors over zeolite/carbon composites prepared from coal gasification fine slag: High quality bio-oil obtaining and mechanism investigation[J]. Fuel, 2023, 339: 126941. [17] LI J W, CHEN Z C, ZHANG X Y, et al. Thermal conversion, kinetics, thermodynamics and empirical optimization of combustion performance of coal gasification fine ash in oxygen-enriched atmosphere[J]. Fuel, 2023, 331: 125882. doi: 10.1016/j.fuel.2022.125882 [18] SHU R, QIAO Q X, GUO F Q, et al. Controlled design of Na-P1 zeolite/porous carbon composites from coal gasification fine slag for high-performance adsorbent[J]. Environmental Research, 2023, 217: 114912. doi: 10.1016/j.envres.2022.114912 [19] 侯志勇, 郝亮亮, 沈小瑞, 等. 煤气化细渣制备吸附材料研究进展[J]. 洁净煤技术, 2021, 27(S2): 201-205.HOU Zhiyong, HAO Liangliang, SHEN Xiaorui, et al. Research progress on preparation of adsorption materials from coal gasification fine slag[J]. Clean Coal Technology, 2021, 27(S2): 201-205(in Chinese). [20] GUO F H, LIU H, ZHAO X, et al. Insights on water temporal-spatial migration laws of coal gasification fine slag filter cake during water removal process and its enlightenment for efficient dewatering[J]. Fuel, 2021, 292: 120274. doi: 10.1016/j.fuel.2021.120274 [21] GUO Y, GUO F H, ZHOU L, et al. Investigation on co-combustion of coal gasification fine slag residual carbon and sawdust char blends: Physiochemical properties, combustion characteristic and kinetic behavior[J]. Fuel, 2021, 292: 120387. doi: 10.1016/j.fuel.2021.120387 [22] HAN S, CHEN H, LONG R Y, et al. Peak coal in China: A literature review[J]. Resources, Conservation and Recycling, 2018, 129: 293-306. doi: 10.1016/j.resconrec.2016.08.012 [23] WANG W D, LIU D H, TU Y N, et al. Enrichment of residual carbon in entrained-flow gasification coal fine slag by ultrasonic flotation[J]. Fuel, 2020, 278: 118195. doi: 10.1016/j.fuel.2020.118195 [24] LYU D P, BAI Y H, WANG J F, et al. Structural features and combustion reactivity of residual carbon in fine slag from entrained-flow gasification[J]. Journal of Fuel Chemistry and Technology, 2021, 49(2): 129-136. doi: 10.1016/S1872-5813(21)60011-7 [25] ZHANG Y C, LI H X, WU C L. Study on distribution, chemical states and binding energy shifts of elements on the surface of gasification fine ash[J]. Research on Chemical Intermediates, 2019, 45(7): 3855-3864. doi: 10.1007/s11164-019-03824-1 [26] DAI G F, ZHENG S J, WANG X B, et al. Combustibility analysis of high-carbon fine slags from an entrained flow gasifier[J]. Journal of Environmental Management, 2020, 271: 111009. doi: 10.1016/j.jenvman.2020.111009 [27] YU W, ZHANG H L, WANG X B, et al. Enrichment of residual carbon from coal gasification fine slag by spiral separator[J]. Journal of Environmental Management, 2022, 315: 115149. doi: 10.1016/j.jenvman.2022.115149 [28] XU S Q, ZHOU Z J, GAO X X, et al. The gasification reactivity of unburned carbon present in gasification slag from entrained-flow gasifier[J]. Fuel Processing Technology, 2009, 90(9): 1062-1070. doi: 10.1016/j.fuproc.2009.04.006 [29] GUO F H, LIU H, GUO Y, et al. Occurrence modes of water in gasification fine slag filter cake and drying behavior analysis—A case study[J]. Journal of Environmental Chemical Engineering, 2021, 9(1): 104585. doi: 10.1016/j.jece.2020.104585 [30] WU S Y, HUANG S, JI L Y, et al. Structure characteristics and gasification activity of residual carbon from entrained-flow coal gasification slag[J]. Fuel, 2014, 122: 67-75. doi: 10.1016/j.fuel.2014.01.011 [31] 张燕, 乐恺, 于卓艺, 等. 粉煤气化细灰微观结构及表面特性试验研究[J]. 煤炭学报, 2021, 46(8): 2681-2689.ZHANG Yan, YUE Kai, YU Zhuoyi, et al. Experimental study on microstructure and surface characteristics of fine ash generated in pulverized coal gasification[J]. Journal of China Coal Society, 2021, 46(8): 2681-2689(in Chinese). [32] PAN C, LIANG Q, GUO X, et al. Characteristics of different sized slag particles from entrained-flow coal gasification[J]. Energy & Fuels, 2016, 30(2): 1487-1495. [33] 郑忆南, 陆海峰, 郭晓镭, 等. 气流床煤气化细灰流动特性研究[J]. 高校化学工程学报, 2018, 32(1): 108-116.ZHENG Yinan, LU Haifeng, GUO Xiaolei, et al. Study on flow properties of fine ash from entrained-flow coal gasification[J]. Journal of Chemical Engineering of Chinese Universities, 2018, 32(1): 108-116(in Chinese). [34] 吴昊东, 邵丰华, 吕鹏, 等. 气流床煤气化细渣结构、性质与其粒度分布关系研究[J]. 燃料化学学报, 2022, 50(5): 513-522.WU Haodong, SHAO Fenghua, LYU Peng, et al. Study on the relationship between structure, properties and size distribution of fine slag from entrained flow gasification[J]. Journal of Fuel Chemistry and Technology, 2022, 50(5): 513-522(in Chinese). [35] 宁永安, 段一航, 高宁博, 等. 煤气化渣组分回收与利用技术研究进展[J]. 洁净煤技术, 2020, 26(S1): 14-19.NING Yong'an, DUAN Yihang, GAO Ningbo, et al. Progress of component recycling and utilization technology of coal gasification slag[J]. Clean Coal Technology, 2020, 26(S1): 14-19(in Chinese). [36] 曲江山, 张建波, 孙志刚, 等. 煤气化渣综合利用研究进展[J]. 洁净煤技术, 2020, 26(1): 184-193.QU Jiangshan, ZHANG Jianbo, SUN Zhigang, et al. Research progress on comprehensive utilization of coal gasification slag[J]. Clean Coal Technology, 2020, 26(1): 184-193(in Chinese). [37] LIU S, CHEN X T, AI W D, et al. A new method to prepare mesoporous silica from coal gasification fine slag and its application in methylene blue adsorption[J]. Journal of Cleaner Production, 2019, 212: 1062-1071. doi: 10.1016/j.jclepro.2018.12.060 [38] YUAN N, TAN K Q, ZHANG X L, et al. Synthesis and adsorption performance of ultra-low silica-to-alumina ratio and hierarchical porous ZSM-5 zeolites prepared from coal gasification fine slag[J]. Chemosphere, 2022, 303: 134839. doi: 10.1016/j.chemosphere.2022.134839 [39] DONG Y C, MAO S B, GUO F Q, et al. Coal gasification fine slags: Investigation of the potential as both microwave adsorbers and catalysts in microwave-induced biomass pyrolysis applications[J]. Energy, 2022, 238: 121867. doi: 10.1016/j.energy.2021.121867 [40] GU Y Y, QIAO X C. A carbon silica composite prepared from water slurry coal gasification slag[J]. Microporous and Mesoporous Materials, 2019, 276: 303-307. doi: 10.1016/j.micromeso.2018.06.025 [41] WANG Y G, SONG Y F, XIA Y Y. Electrochemical capacitors: Mechanism, materials, systems, characterization and applications[J]. Chemical Society Reviews, 2016, 45(21): 5925-5950. doi: 10.1039/C5CS00580A [42] TIAN X D, CHEN Z C, HOU J, et al. Sustainable utilization method of using coal gasification fine ash to prepare activated carbon for supercapacitor[J]. Journal of Cleaner Production, 2022, 363: 132524. doi: 10.1016/j.jclepro.2022.132524 [43] ZHU D D, XUE B, JIANG Y S, et al. Using chemical experiments and plant uptake to prove the feasibility and stability of coal gasification fine slag as silicon fertilizer[J]. Environmental Science and Pollution Research, 2019, 26(6): 5925-5933. doi: 10.1007/s11356-018-4013-8 [44] WANG Y K, LIANG L P, ZHU B S, et al. Economical preparation of Fe3O4/C/CG and Fe/C/CG composites as microwave absorbents by recycling of coal gangue[J]. Materials Research Bulletin, 2022, 146: 111573. doi: 10.1016/j.materresbull.2021.111573 [45] WANG Y K, LIANG L P, LI Y Y, et al. Facile construction of low-cost and high-efficiency microwave absorbent of Co/C/CG composite with dual-enhancement performance[J]. Diamond and Related Materials, 2022, 126: 109038. doi: 10.1016/j.diamond.2022.109038 [46] ANGAPPAN M, BORA P J, VINOY K J, et al. Microwave absorption efficiency of poly(vinyl-butyral)/ultra-thin nickel coated fly ash cenosphere composite[J]. Surfaces and Interfaces, 2020, 19: 100430. doi: 10.1016/j.surfin.2020.100430 [47] WANG S, XIAO N, ZHOU Y, et al. Lightweight carbon foam from coal liquefaction residue with broad-band microwave absorbing capability[J]. Carbon, 2016, 105: 224-226. doi: 10.1016/j.carbon.2016.04.040 [48] MAO L T, LI L X, LIANG L P, et al. Magnetic carbon composites derived from coal hydrogasification residue for microwave absorption[J]. Physica Status Solidi A, 2022, 219(14): 2200152. doi: 10.1002/pssa.202200152 [49] 中国国家标准化管理委员会. 煤的工业分析方法: GB/T 212—2008[S]. 北京: 中国标准出版社, 2008.Standardization Administration of the People's Republic of China. Proximate analysis of coal: GB/T 212—2008[S]. Beijing: China Standards Press, 2008(in Chinese). [50] 中国国家标准化管理委员会. 煤中碳和氢的测定方法: GB/T 476—2008[S]. 北京: 中国标准出版社, 2008.Standardization Administration of the People's Republic of China. Determination of carbon and hydrogen in coal: GB/T 476—2008[S]. Beijing: China Standards Press, 2008(in Chinese). [51] 中国国家标准化管理委员会. 煤中氮的测定方法: GB/T 19227—2008[S]. 北京: 中国标准出版社, 2008.Standardization Administration of the People's Republic of China. Determination of nitrogen in coal: GB/T 19227—2008[S]. Beijing: China Standards Press, 2008(in Chinese). [52] 中国国家标准化管理委员会. 煤中全硫的测定方法: GB/T 214—2007[S]. 北京: 中国标准出版社, 2007.Standardization Administration of the People's Republic of China. Determination of total sulfur in coal: GB/T 214—2007[S]. Beijing: China Standards Press, 2007(in Chinese). [53] 中国环境科学研究院固体废物污染控制技术研究所. 固体废物 浸出毒性浸出方法 硫酸硝酸法: HJ/T 299—2007[S]. 北京: 中国环境科学出版社, 2007.Institute of Solid Waste Pollution Control Technology, Chinese Academy of Environmental Sciences. Solid waste—Extraction procedure for leaching toxicity—Sulphuric acid & nitric acid method: HJ/T 299—2007[S]. Beijing: China Environmental Science Press, 2007(in Chinese). [54] 中国国家标准化管理委员会. 危险废物鉴别标准 浸出毒性鉴别: GB/T 5085.3—2007[S]. 北京: 中国标准出版社,2007.Standardization Administration of the People's Republic of China. Identification standards for hazardous wastes—Identification for extraction toxicity: GB/T 5085.3—2007[S]. Beijing: China Standards Press, 2007(in Chinese). -
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