薄煤层掘进工作面气幕控尘技术研究.pdf

硕士学位论文 薄煤层掘进工作面气幕控尘技术研究 Study on Dust Control Technique by Air Curtain for Heading Face in Thin Coal Seam 作 者刘德爽 导 师谢耀社 教授 中国矿业大学 二○一七年五月 万方数据 中图分类号 TD714 学校代码 10290 UDC 622 密 级 公开 中国矿业大学 硕士学位论文 薄煤层掘进工作面气幕控尘技术研究 Study on Dust Control Technique by Air Curtain for Heading Face in Thin Coal Seam 作 者 刘德爽 导 师 谢耀社 申请学位 工学硕士 培养单位 矿业学院 学科专业 采矿工程 研究方向 灾害防治 答辩委员会主席 万志军 评 阅 人 杨胜强 董敬源 二○一七年五月 万方数据 学位论文使用授权声明学位论文使用授权声明 本人完全了解中国矿业大学有关保留、使用学位论文的规定，同意本人所撰 写的学位论文的使用授权按照学校的管理规定处理 作为申请学位的条件之一， 学位论文著作权拥有者须授权所在学校拥有学位 论文的部分使用权，即①学校档案馆和图书馆有权保留学位论文的纸质版和电 子版，可以使用影印、缩印或扫描等复制手段保存和汇编学位论文；②为教学和 科研目的，学校档案馆和图书馆可以将公开的学位论文作为资料在档案馆、图书 馆等场所或在校园网上供校内师生阅读、浏览。另外，根据有关法规，同意中国 国家图书馆保存研究生学位论文。 （保密的学位论文在解密后适用本授权书） 。 作者签名 导师签名 年 月 日 年 月 日 万方数据 致谢致谢 时光荏苒，岁月如梭。研究生初入学时场景历历在目，转眼已到毕业离校时 刻。师从导师谢耀社老师三载，谢老师严谨的治学态度，精益求精的工作作风以 及独特的思维方式令我受益匪浅。谢老师的谆谆教导、耐心解惑都成为了我人生 的宝贵财富。毕业论文写作期间，导师谢耀社教授从论文的选题到论文的撰写和 修改，倾注了无数心血。 春去秋来，潮起潮落。三年的求学时光，充满着历练和收获。收获了学业的 成长进步，收获了珍贵的师生情谊，收获了师兄同窗的支持和帮助，收获了三年 美好校园生活。在此，向谢老师致以深深的敬意和诚挚的感谢，向师兄、师弟致 以真诚的感谢。 衷心感谢矿业工程学院的领导和老师们多年来在学习和生活上给予的关心 和帮助，你们为人师表的风范令我敬仰，严谨治学的态度令我敬佩。 感谢煤炭资源与安全开采国家重点实验室的各位老师在论文实验过程中给 予的大力支持和无私的帮助。 感谢王帅、熊佳文、汤进、姚毅峰、崔泰峰等师兄弟在我学习期间和论文撰 写过程中的鼎力相助，感谢李芳芳同学对论文中英文翻译的指导和校核。 感谢我的父母在我这么多年求学路上做我的坚强后盾， 在我面临人生选择的 迷茫之际，为我排忧解难，他们对我无私的爱与照顾是我不断前进的动力。 感谢各位专家和学者在百忙之中评审论文，衷心希望得到您的指导和帮助。 感谢论文所引用文献的作者。 感谢所有帮助和关心我的人。 最后本人还是要感谢在百忙之中评审本文并提出宝贵意见的各位专家教授 刘德爽 二〇一七年五月 万方数据 I 摘摘 要要 薄煤层掘进工作面作业空间狭小和施工进度快的特点， 加重了粉尘聚集和粉 尘浓度超限。本文以-290m 掘进工作面工况条件为基础，研究了气幕控尘技术改 善巷道粉尘浓度超标问题。通过理论分析， 得出粉尘向巷道后方运移的主要动力 是风流的运动。掘进工作面风流包括射流区、顺流区、涡流区、逆转区，最有利 的通风方式为“U”形附壁层流。 利用 Fluent 建立气-固两相流模型，得出供风量增大到 250m3/min 时，风流 射流区长度和风筒出风口距迎头面的长度相近， 粉尘分布区域减小。 当 Lf6m 时， 司机位置处所受扰动风速减小，回风流携带粉尘对其影响较小。同时，截割头扰 动风速的增大，也会加大粉尘向掘进机方向运移的距离，增大掘进机扒装煤岩作 业的逸尘扩散范围。掘进机产尘量的增大，直接引起巷道平均粉尘浓度增大。且 截割头产尘量 J 超过 120mg/s 时， 掘进机司机位置和后端行人作业区的呼吸性粉 尘的浓度均严重超出国家规定安全作业环境值。 气幕开启后形成冲击射流，包含自由射流区、射流冲击区和附壁射流区，分 析气幕出风口宽度与气幕卷吸风量的变化关系，可通过选择较小出风口宽度，提 高煤层掘进工作面气幕出风口风速来实现气幕卷吸风量的要求。当出口风速 Vq7.0m/s 时，掘进机司机位置处粉尘浓度较低。后端行人作业区 X1整体大于后 端行人作业区 X2的粉尘浓度，表明粉尘高浓度区域被控制在回风侧巷帮附近， 气幕控制效率最高。 单独增大回风侧导流气幕风机的长度会降低掘进机司机位置 和后端行人作业区的粉尘浓度。当回风侧导流气幕风机长度 LFz23m 时，掘进面 气幕控制效果明显。 对比气幕开启前后，掘进机司机位置处粉尘浓度下降 76.92，降为 3.597mg/m3，达到国家规定的安全作业限值。以矿井湿式除尘实验平台为基础进 行试验研究得出气幕出风口宽度、风速及倾角分别为 0.02m、7m/s、10 时，气 幕控尘效率最高达到 82.3，与理论分析和数值模拟结果相吻合。 论文共有 75 幅图，21 个表，参考文献 99 篇。 关键词关键词薄煤层；掘进工作面；Fluent；气幕控尘；冲击射流；控尘效率 万方数据 II Abstract The driving face of thin seam features small work space and quick construction work, which makes dust accumulation and dust concentration over its standard. Based on the condition of level driving face, namely negative 290m, the paper studies lower dust concentration of roadway through dust control by air curtain. After analyzing the theory, the paper concludes that the dust’s main driving force to move backward roadway is air current movement. The air current of driving face includes jet zone, downstream zone, vortex zone and reverse zone. The best way of airing is U-typed wall-attached laminar flow. By building two-phase flow model of gas and solid, we get that volume of air supply stands at 250m3/min, the length of jet zone of air current and air outlet of hair dryer is close while the distribution zone of dust lowers. When Lf equals 6m, the driver position is influenced less by disturbance wind speed and dust of return current. At the same time, quicker disturbance wind speed of cutting head will make the distance of dust to heading machine longer and dust zone of hoeing coal petrography larger. The more dust brought by heading machine, the more average dust concentration of roadway. When dust J of cutting head exceeds 120mg/s, the respirable dust concentration of driver position of heading machine and back work space will seriously violates national standard. Opening air curtain will s impact jet flow, including free jet flow zone, jet impact zone and wall-attached jet flow zone. By analyzing the relations between width of air curtain wind outlet and wind volume of air curtain, small width of outlet will improve wind speed of air curtain of heading face, which will achieve wind volume of air curtain. When wind speed of outlet stands at Vq equals 7.0m/s, the dust concentration of driver position of heading machine is lower. When dust concentration of back work space X1 is greater than X2, the high dust concentration zone is controlled near return air and the control rate of air curtain is high. Lengthening draught fan of diversion air curtain of return air alone will lower dust concentration of driver position of heading machine and back work space. When the length of draught fan of diversion air curtain of return air is LFz2 equals 3m, the controlling effect of heading face is favorable. Comparing conditions of opening air curtain or not, we get that when dust concentration of driver position of heading machine lower by 76.92 to 3.5972mg/m3, it meets national standard. Experiment study based on wet dust removal of mine reveals 万方数据 III that when width of air curtain outlet, wind speed and angle of tilt stands at 0.02m, 7m/s and 10 , the controlling effect rate of air curtain registers up to 82.3, which cons to theoretical analysis and numerical modeling results. This dissertation consists of 75 pictures, 21 tables and 99 references. Keywords thin coal seam; heading face; Fluent; dust control by air curtain; impact jet flow; dust-control efficiency 万方数据 IV 目目 录录 摘摘 要要 ........................................................................................................................... I 目目 录录 ........................................................................................................................ IV 图清单图清单 ..................................................................................................................... VIII 表清单表清单 ..................................................................................................................... XIII 变量注释表变量注释表 ............................................................................................................... XV 1 绪论绪论 ........................................................................................................................... 1 1.1 研究背景及意义..................................................................................................... 1 1.2 国内外研究现状..................................................................................................... 4 1.3 薄煤层掘进面防尘技术面临的主要问题........................................................... 11 1.4 主要研究内容及方法........................................................................................... 12 2 薄煤层掘进工作面薄煤层掘进工作面粉尘特性及其运移动力分析粉尘特性及其运移动力分析 ................................................. 14 2.1 工况条件............................................................................................................... 14 2.2 掘进工作面粉尘基本特性................................................................................... 16 2.3 掘进工作面粉尘运移受力分析........................................................................... 19 2.4 掘进面气幕风流通道构筑.................................................................................... 23 2.5 掘进工作面水力直径和湍流强度计算............................................................... 26 2.6 本章小结............................................................................................................... 28 3 薄煤层掘进工作面风流及粉尘分布规律模拟研究薄煤层掘进工作面风流及粉尘分布规律模拟研究 ............................................. 29 3.1 气-固两相流数学模型选择 ................................................................................. 29 3.2 掘进工作面模型建立........................................................................................... 32 3.3 掘进工作面网格划分及边界条件参数设定....................................................... 34 3.4 掘进面风流及粉尘浓度数值模拟及结果分析................................................... 36 3.5 本章小结............................................................................................................... 55 4 薄煤层掘进工作面气幕控尘及其效率优化薄煤层掘进工作面气幕控尘及其效率优化 ......................................................... 57 4.1 气幕控尘技术原理及控尘理论........................................................................... 57 4.2 气幕控尘参数理论计算....................................................................................... 60 4.3 掘进工作面气幕控尘对比研究........................................................................... 61 4.4 掘进工作面气幕控尘效率优化........................................................................... 68 4.5 本章小结............................................................................................................... 76 5 薄煤层掘进工作面气幕控尘试验研究薄煤层掘进工作面气幕控尘试验研究 ................................................................. 78 万方数据 V 5.1 试验用粉尘样品制备和浓度测定....................................................................... 78 5.2 粉尘粒径大小测定和呼吸性粉尘占比............................................................... 80 5.3 模拟截割头产尘系统和气幕风机布置............................................................... 81 5.4 气幕出风口宽度和风速变化时的粉尘浓度变化............................................... 82 5.5 本章结论............................................................................................................... 87 6 研究研究结论结论与展望与展望 ..................................................................................................... 89 6.1 主要研究结论....................................................................................................... 89 6.2 问题与展望........................................................................................................... 90 参考文献参考文献 ..................................................................................................................... 92 作者简历作者简历 ..................................................................................................................... 98 论文原创性声明论文原创性声明 ......................................................................................................... 99 学位论文数据集学位论文数据集 ....................................................................................................... 100 万方数据 VI Contents Abstract ........................................................................................................................ II Contents ......................................................................................................................VI List of Figures ......................................................................................................... VIII List of Tables ........................................................................................................... XIII List of Variables........................................................................................................ XV 1 Introduction ............................................................................................................... 1 1.1 Research Backgrounds and Significances ............................................................... 1 1.2 Research Status at Home and Abroad ...................................................................... 4 1.3 The Problem of Dust Control on Heading Face of Thin Seam .............................. 11 1.4 Main Research Contents and s .................................................................. 12 2 The Dust’s Characteristics and its Moving Force Analysis of Heading Face in Thin Coal Seam .......................................................................................................... 14 2.1 Engineering Condition ........................................................................................... 14 2.2 Basic Characteristics of Dust of Heading Face ...................................................... 16 2.3 Force Analysis of Dust Movement of Heading Face ............................................. 19 2.4 Construction of Air Flow Channel of Air Curtain in Thin Heading Face .............. 23 2.5 Hydraulic Diameter and Turbulence Intensity Calculation of Heading Face ........ 26 2.6 Brief Summary ....................................................................................................... 28 3 Simulation Study on Distribution Law of Airflow and Dust of Heading Face in Thin Coal Seam .......................................................................................................... 29 3.1 Analysis and Choice of Math Model of Gas and Solid .......................................... 29 3.2 Establish Model of Heading Face .......................................................................... 32 3.3 Mesh Generation and Parameter Setting of Boundary Conditions of Heading Face ...................................................................................................................................... 34 3.4 Numerical Simulation and Results Analysis of Airflow and Dust Concentration of Heading Face ............................................................................................................... 36 3.5 Brief Summary ....................................................................................................... 55 4 Dust Control by Air Curtain and Its Upgrading of Heading Face in Thin Seam ............................................................................................................................ 57 4.1 Principle and Theory of Dust Control by Air Curtain Technique .......................... 57 万方数据 VII 4.2 Theoretical Calculation of Parameter of Dust Control by Air Curtain .................. 60 4.3 Study on Comparison of Dust Control by Air Curtain of Heading Face ............... 61 4.4 Promote the Efficiency of Dust Control by Air Curtain in Heading Face ............. 68 4.5 Brief Summary ....................................................................................................... 76 5 Experiment Study on Dust Control by Air Curtain of Heading Face of Thin Seam ...................................................................................................................................... 78 5.1 Dust sample instrument and concentration tests .................................................... 78 5.2 Measurement of dust diameter and proportion of respirable dust .......................... 80 5.3 Modeling dust production system of cutting head and arrangement of air curtain draught fan ................................................................................................................... 81 5.4 Change of dust concentration when width of air curtain outlet and wind speed change .......................................................................................................................... 82 5.5 Brief Summary ............