煤沥青球气固流化磨损特性实验研究

doi:10.11949/0438-1157.20211322

摘要/Abstract

摘要：

固体颗粒的流化磨损是流态化技术重要的基础问题之一，气固流动过程中颗粒的磨损特性以及两种磨损机制的研究，对流态化技术的应用具有重要意义。针对煤沥青球设计可视化冷态流化实验系统，研究表观气速、初始粒径和高径比对颗粒流化磨损行为的影响，探讨颗粒流化磨损机理。结果表明：经过流化磨损后，仍在初始粒径范围内的煤沥青颗粒球形度增加，表面更光滑；流化磨损过程受到体相断裂和表面剥层两种磨损机制的共同作用：高速磨损阶段由表面剥层主导，低速磨损阶段表面剥层和体相断裂同时存在，稳态阶段再次由表面剥层主导；提高表观气速和高径比、降低初始粒径均会加剧流化磨损过程，流化数从2.7增加到3.9，体相断裂和表面剥层程度分别增加了3.6%和1.4%。

关键词: 煤沥青球, 流态化, 磨损, 磨损机制, 表面剥层, 体相断裂, 动态学

Abstract:

Attrition of solid particles is one of the important problems of fluidization technology. The study of particle attrition characteristics and two attrition mechanisms in the process of gas-solid flow is of great significance to the application of fluidization technology. In this paper, a visualized cold fluidized bed was designed for coal tar pitch particles to study the effects of gas velocity, initial particle size and height-diameter ratio on attrition behavior, and to discuss attrition mechanisms. The results show that the sphericity of coal tar pitch particles increases and the surface tends to be smoother after fluidization, but the average diameter decreases. The attrition process is affected by two attrition mechanisms, fragmentation and abrasion respectively. In the high-speed attrition stage, abrasion plays a dominant role, and in the low-speed attrition stage, both fragmentation and abrasion work simultaneously. In the steady state, abrasion dominates again. In addition, increasing gas velocity and height-diameter ratio, decreasing initial particle size all aggravate the attrition process. With the fluidization number increasing from 2.7 to 3.9, the rate of fragmentation and abrasion increases by 3.6% and 1.4%, respectively. When height-diameter ratio doubles, the rate of fragmentation and abrasion increases by 1.4% and 8.2%, respectively.

Key words: coal tar pitch particles, fluidization, attrition, attrition mechanism, fragmentation, abrasion, dynamics

中图分类号:

TQ 012

周楠, 王簪, 邵应娟, 钟文琪. 煤沥青球气固流化磨损特性实验研究[J]. 化工学报, 2022, 73(2): 587-594.

Nan ZHOU, Zan WANG, Yingjuan SHAO, Wenqi ZHONG. Experimental study on attrition characteristics of coal tar pitch particles during gas-solid fluidization[J]. CIESC Journal, 2022, 73(2): 587-594.

图/表 7

表1 煤沥青球的物理性质

Table1 Physical properties of coal tar pitch particles

床料	粒径范围d_p/mm	表观密度ρ_p/(kg/m³)	堆积空隙率 $ε$
煤沥青	0.4~1.2	1200	0.4

表1 煤沥青球的物理性质

Table1 Physical properties of coal tar pitch particles

床料	粒径范围d_p/mm	表观密度ρ_p/(kg/m³)	堆积空隙率 $ε$
煤沥青	0.4~1.2	1200	0.4

图1 煤沥青球流化磨损实验系统1—流化床床体；2—进料口；3—金属布风板；4—布风室；5—转子流量计；6—阀门；7—空气压缩机；P—压力表

Fig.1 Experimental system of attrition of coal tar pitch particles in a fluidized bed

表2 实验工况设计

Table 2 Experimental condition design

实验参数	编号	表观气速/（m/s）	初始粒径范围/mm	高径比
表观气速	A1	0.7	0.8~1.0	0.75
	N	0.8	0.8~1.0	0.75
	A2	0.9	0.8~1.0	0.75
	A3	1.0	0.8~1.0	0.75
初始粒径	B1	0.8	0.4~0.6	0.75
	B2	0.8	0.6~0.8	0.75
	N	0.8	0.8~1.0	0.75
	B3	0.8	1.0~1.2	0.75
高径比	C1	0.8	0.8~1.0	0.56
	N	0.8	0.8~1.0	0.75
	C2	0.8	0.8~1.0	0.94
	C3	0.8	0.8~1.0	1.13

图2 磨损率、磨损速率随磨损时间的变化

Fig.2 Changes of attrition rate and attrition velocity with time

图3 不同因素对磨损率、磨损速率的影响

Fig.3 Effect of different factors on attrition rate and attrition velocity

图4 不同流化时间下煤沥青球的磨损结果：各粒径范围的SEM照片(a)；表面剥层率、体相断裂率随磨损时间的变化(b)；煤沥青球的粒径分布随时间的变化(c)

Fig.4 Attrition results of coal tar pitch particles under different fluidization time： SEM images of different particle size range(a)； Changes of abrasion rate and fragmentation rate with attrition time(b)； Changes of particle size distribution with time (c)

图5 不同实验参数对表面剥层率、体相断裂率的影响

Fig.5 Effect of different factors on abrasion rate and fragmentation rate

参考文献 34

1	郭慕孙, 李洪钟. 流态化手册[M]. 北京: 化学工业出版社, 2008: 1-7.
	Guo M S, Li H Z. Handbook of Fluidization[M]. Beijing: Chemical Industry Press, 2008: 1-7.
2	Werther J, Reppenhagen J. Catalyst attrition in fluidized-bed systems[J]. AIChE Journal, 1999, 45(9): 2001-2010.
3	李路明, 高新宇, 田佩玉, 等. 脱硝催化剂堵塞磨损问题工程案例分析探究[J]. 锅炉制造, 2021(3): 39-42.
	Li L M, Gao X Y, Tian P Y, et al. Case study on blockage and wear of de-NO_x catalyst[J]. Boiler Manufacturing, 2021(3): 39-42.
4	Hatanaka T, Yoda Y. Attrition of ilmenite ore during consecutive redox cycles in chemical looping combustion[J]. Powder Technology, 2019, 356: 974-979.
5	Li D F, Ke X W, Yang H R, et al. The ash formation and attrition characteristics of an Indonesia lignite coal ash for a 550 MWe ultra supercritical CFB boiler[J]. Chemical Engineering Research and Design, 2019, 147: 579-586.
6	Bjorklund I S, Dygert J C. Small scale tests for attrition resistance of solids in slurry systems[J]. AIChE Journal, 1968, 14(4): 553-557.
7	公铭扬, 李晓刚, 杜伟, 等. 流化催化剂磨损机制的研究进展[J]. 摩擦学学报, 2007, 27(1): 91-96.
	Gong M Y, Li X G, Du W, et al. Research progress on fluid catalyst attrition[J]. Tribology, 2007, 27(1): 91-96.
8	Amblard B, Bertholin S, Bobin C, et al. Development of an attrition evaluation method using a Jet Cup rig[J]. Powder Technology, 2015, 274: 455-465.
9	Thon A, Werther J. Attrition resistance of a VPO catalyst[J]. Applied Catalysis A: General, 2010, 376(1/2): 56-65.
10	Choi J H, Moon Y S, Yi C K, et al. Attrition of zinc-titanate sorbent in a bubbling fluidized bed[J]. Journal of the Taiwan Institute of Chemical Engineers, 2010, 41(6): 656-660.
11	Yao X, Zhang H, Yang H R, et al. An experimental study on the primary fragmentation and attrition of limestones in a fluidized bed[J]. Fuel Processing Technology, 2010, 91(9): 1119-1124.
12	陶中东, 顾正东, 吴东方. 颗粒流化磨损研究进展[J]. 化工进展, 2014, 33(10): 2535-2539, 2564.
	Tao Z D, Gu Z D, Wu D F. Research progress on fluidized particle attrition[J]. Chemical Industry and Engineering Progress, 2014, 33(10): 2535-2539, 2564.
13	Li F, Briens C, Berruti F, et al. Particle attrition with supersonic nozzles in a fluidized bed at high temperature[J]. Powder Technology, 2012, 228: 385-394.
14	Alonso M, Arias B, Fernández J R, et al. Measuring attrition properties of calcium looping materials in a 30 kW pilot plant[J]. Powder Technology, 2018, 336: 273-281.
15	Zhang Z, Ghadiri M. Impact attrition of particulate solids. Part 2: Experimental work[J]. Chemical Engineering Science, 2002, 57(17): 3671-3686.
16	Wu D F, Gu Z D, Li Y D. Attrition of catalyst particles in a laboratory-scale fluidized-bed reactor[J]. Chemical Engineering Science, 2015, 135: 431-440.
17	许家豪. 提升管内催化剂磨损研究及数值模拟[D]. 东营: 中国石油大学(华东), 2016.
	Xu J H. Study and numerical simulation of catalyst attrition in the riser reactor[D]. Dongying: China University of Petroleum (East China), 2016.
18	Yang Z Q, Ren W G, Zhang L, et al. Limestone particle attrition and size distribution in a bench scale bubbling fluidized bed[J]. Global Nest Journal, 2015, 17(2): 236-247.
19	Park Y S, Kim H S, Shun D, et al. Attrition characteristics of alumina catalyst for fluidized bed incinerator[J]. Korean Journal of Chemical Engineering, 2000, 17(3): 284-287.
20	王永邦, 刘小军, 李泽斯, 等. 沥青球在流化床反应器中氧化不熔化及后续炭化行为的研究[J]. 炭素技术, 2010, 29(6): 5-8, 12.
	Wang Y B, Liu X J, Li Z S, et al. Oxidative stabilization of pitch spheres in fluidized bed and their carbonization behavior[J]. Carbon Techniques, 2010, 29(6): 5-8, 12.
21	郭源, 邵应娟, 钟文琪, 等. 煤沥青球的氧化不熔化过程特性[J]. 化工学报, 2018, 69(1): 499-506.
	Guo Y, Shao Y J, Zhong W Q, et al. Characteristics of oxidation stabilization process of coal pitch based spheres[J]. CIESC Journal, 2018, 69(1): 499-506.
22	李开喜. 一步法低能耗制备沥青球的技术: 103695019A[P]. 2014-04-02.
	Li K X. One-step and low energy consumption preparation technology of pitch spheres: 103695019A[P]. 2014-04-02.
23	金涌. 流态化工程原理[M]. 北京: 清华大学出版社, 2001: 1-7.
	Jin Y. Fluidization Engineering Principles[M]. Beijing: Tsinghua University Press, 2001: 1-7.
24	任伟光. 低浓度甲烷催化剂颗粒气固流化态的磨损特性研究[D]. 重庆: 重庆大学, 2016.
	Ren W G. Experimental study on attrition characteristics of low-concentration methane catalyst particles[D]. Chongqing: Chongqing University, 2016.
25	Wu D F, Wu F H, Gu Z D. Catalyst attrition in an ASTM fluidized bed[J]. Catalysis Today, 2016, 264: 70-74.
26	Zakeri M, Samimi A, Khorram M, et al. Effect of forming on selectivity and attrition of co-precipitated Co-Mn Fischer-Tropsch catalysts[J]. Powder Technology, 2010, 200(3): 164-170.
27	Kang D H, Ko C K, Lee D H. Attrition characteristics of iron ore by an air jet in gas-solid fluidized beds[J]. Powder Technology, 2017, 316: 69-78.
28	Reppenhagen J, Werther J. Catalyst attrition in cyclones[J]. Powder Technology, 2000, 113(1/2): 55-69.
29	Yin R L, Wang K, Han B B, et al. Structural evaluation of coal-tar-pitch-based carbon materials and their Na⁺ storage properties[J]. Coatings, 2021, 11(8): 948.
30	Tavares L M. Analysis of particle fracture by repeated stressing as damage accumulation[J]. Powder Technology, 2009, 190(3): 327-339.
31	Ergun S. Fluid flow through packed columns[J]. Chemical Engineering Progress, 1952, 48(2): 89-94.
32	Okhovat-Alavian S M, Behin J, Mostoufi N. Investigating bubble dynamics in a semi-cylindrical gas-solid fluidized bed[J]. Powder Technology, 2020, 370: 129-136.
33	Gao Q H, Wang T, Tang T Q, et al. Macroscopic and microscopic flow characteristics of particles in a sound assisted bubbling fluidized bed[J]. Chemical Engineering and Processing - Process Intensification, 2020, 156: 108102.
34	Miao M, Yao X, Zhang S M, et al. Attrition performance and morphology of limestone under different conditions in fluidized bed[J]. Fuel Processing Technology, 2021, 221: 106939.

[1]	王凯玥, 马永丽, 李琛, 刘明言. 气液固微型流化床的气液传质系数[J]. 化工学报, 2022, 73(8): 3529-3540.
[2]	周晨阳, 贾颖, 赵跃民, 张勇, 付芝杰, 冯昱清, 段晨龙. 介尺度视角下干法重介流态化分选过程强化[J]. 化工学报, 2022, 73(6): 2452-2467.
[3]	胡善伟, 刘新华. 气固流化系统多尺度跨流域EMMS建模[J]. 化工学报, 2022, 73(6): 2514-2528.
[4]	孔令菲, 陈延佩, 王维. 气固流态化中颗粒介尺度结构的动力学研究[J]. 化工学报, 2022, 73(6): 2486-2495.
[5]	蒋鸣, 周强. 气固流化床介尺度结构形成机制及过滤曳力模型研究进展[J]. 化工学报, 2022, 73(6): 2468-2485.
[6]	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.
[7]	宋伟, 李万佳, 俞树荣, 马荣荣. 热力耦合下TC4合金微动磨损行为影响的研究[J]. 化工学报, 2022, 73(3): 1324-1334.
[8]	张志敏, 丁雪兴, 张兰霞, 力宁, 司佳鑫. 浮环密封端面分形磨损预估模型及数值分析[J]. 化工学报, 2022, 73(12): 5526-5536.
[9]	马永丽, 刘明言, 李琛, 胡宗定. 液固和气液固微型流态化研究进展[J]. 化工学报, 2022, 73(1): 46-58.
[10]	苏伟, 芦志飞, 张小松. 竖直超疏水翅片间霜层动态生长特性[J]. 化工学报, 2021, 72(S1): 244-256.
[11]	张溪,张立龙,李瑞,吴玉龙. 基于能量集成的秸秆生物质快速热解生命周期评价[J]. 化工学报, 2021, 72(5): 2792-2800.
[12]	李海燕, 刘欢, 张秀菊, 王阁义, 周巧燕, 陈同舟, 姚洪. HVOF喷涂用于提高锅炉换热面耐磨损耐腐蚀性能综述[J]. 化工学报, 2021, 72(4): 1833-1846.
[13]	王荘, 吕潇, 邵媛媛, 祝京旭. 流态化的往昔寻觅及未来启示[J]. 化工学报, 2021, 72(12): 5904-5927.
[14]	马润梅, 赵祥, 李双喜, 刘兴华, 许灿. 颗粒介质用机械密封热力耦合变形及摩擦磨损研究[J]. 化工学报, 2021, 72(11): 5726-5737.
[15]	陆俊杰, 张炜, 谢方民, 焦永峰. 一种自适应柱状密封气膜特性分析[J]. 化工学报, 2020, 71(S1): 346-354.