变径液固流化床粗煤泥分选机制及调控
发布时间：2018-09-15 19:39
【摘要】：粗煤泥颗粒的高效物理分选与回收对于资源循环利用和环境保护具有重要的意义。本文以粗煤泥物料为分选研究对象,研究粗煤泥物料的宏观密度组成和粒度组成,得到物料的密度组成和粒度组成数据。微观角度,借助扫描电镜对分选前后物料样品进行拍照,运用JMicro Vision软件分析微观状态下,粗煤泥颗粒的一维和二维灰度变化情况,直观表述出粗煤泥颗粒性质以及分选前后粗煤泥物质组成成分的微观变化。同时,借助X射线荧光光谱分析技术定量分析粗煤泥分选前后物料组成成分的迁移变化,为验证粗煤泥分选的可行性提供先进技术支撑。采用新型变径液固流化床分选系统分选粗煤泥,具有重要的实际意义和应用价值。基于粗煤泥物料中煤炭与矸石颗粒的较大密度差异,针对粗煤泥物料的分选,设计新型模块化变径液固流化床分选机,建立新型结构化变径液固流化床分选系统,包括模块化设计分选机和配套设备。研究颗粒及颗粒群在变径液固流化床分选机中弛豫现象,首先详细分析单颗粒在流体弛豫过程的受力情况,通过对比确定粗煤泥颗粒在变径液固流化床分选系统中主要受力,忽略次要受力。针对颗粒群弛豫,提出颗粒群运动过程中颗粒所受阻力阻力系数仅与颗粒附近流体流动雷诺数有关的假设。同时,介尺度分析能量最小原理的基础上,提出颗粒聚团局部能量最小平衡原理假设,分析解释颗粒流体系统中颗粒聚团行为。采用FLUENT软件与EDEM耦合计算,研究变径液固流化床分选粗煤泥过程中颗粒的运动情况以及床体内部流场的变化。通过分析颗粒运动情况,获得不同颗粒在床体中运动的速度变化,轨迹变化情况。在水流作用区域中,不同密度的颗粒在水流的作用下实现分离和分选。然而当颗粒沿壁面运动时,不同颗粒聚集在一起,影响颗粒的分离过程。为了解决颗粒在壁面聚集的问题。本章探究顶水孔的加入对于颗粒分选的影响。通过利用FLUENT软件分顶水对变径液固流化床中流场分布的影响,以及顶水对壁面附件区域流体速度场的影响,验证顶水孔的可行性和有效性。采用变径液固流化床分选系统实现对-3+0.5mm粗煤泥物料的分选和有效回收。在考察倾斜角度、水流量、给料浓度、给料速度和溢流流量对粗煤泥可燃体回收率影响的基础上,确定倾斜角度、水流量和给料浓度为可控主要影响因素,借助正交试验设计软件,设计并开展三因素三水平正交试验。确定影响因素的最佳水平和水平最佳组合。借助扫描电极分析和X射线荧光光谱分析技术,对分选前后物料进行分析测试,分析结果表明:变径液固流化床分选系统能够有效实现粗煤泥矸石的脱出和可燃体的高效回收。根据变径液固流化床分选系统溢流流量变化的特点,探索模糊神经网络控制在溢流流量控制中的应用,对于非线性、多变量的变径液固流化床分选系统,本文构建了双输入单输出的自适应模糊神经网络控制系统,利用MATLAB/Simulink软件对控制系统进行建模与仿真计算,优化控制系统,得到合适的控制参数。仿真结果显示:自适应模糊神经网络控制器具有比模糊控制器更加快速的反应时间,同时超调量比较小。这将提高控制系统的反应能力以及鲁棒性,减少稳态误差。模型控制过程非常平稳快速。
[Abstract]:High efficient physical separation and recovery of coarse slime particles is of great significance for resource recycling and environmental protection. In this paper, coarse slime materials are selected as the research object, the macro-density and particle size composition of coarse slime materials are studied, and the data of density and particle size composition are obtained. The material samples were photographed before and after sorting, and the changes of one-dimensional and two-dimensional gray levels of coarse slime particles in micro-state were analyzed by JMicro Vision software. The properties of coarse slime particles and the Micro-changes of components of coarse slime before and after sorting were described intuitively. It is of great practical significance and application value to adopt a new type of variable diameter liquid-solid fluidized bed separation system to separate coarse coal slime. Based on the large density difference between coal and gangue particles in coarse coal slime materials, the separation of coarse coal slime materials is aimed at. A new type of modular variable-diameter liquid-solid fluidized bed separator was designed and a new type of structured variable-diameter liquid-solid fluidized bed separator was established, including modular design separator and supporting equipment. The main force of coarse slime particles in the variable-diameter liquid-solid fluidized bed separation system is determined by comparison, and the secondary force is neglected. The assumption that the drag coefficient of particles in the process of particle group movement is only related to the Reynolds number of fluid flow near the particles is proposed. Based on the hypothesis of local energy minimization equilibrium of particle agglomeration, the behavior of particle agglomeration in granular fluid system is analyzed and explained. The movement of particles and the change of flow field in the bed during the separation of coarse slime in a variable-diameter liquid-solid fluidized bed are studied by using FLUENT software coupled with EDEM. In order to solve the problem of particle aggregation on the wall, this chapter explores the addition of top water holes. The feasibility and validity of the top hole are verified by the influence of the top water on the flow field distribution in the variable diameter liquid-solid fluidized bed and the influence of the top water on the fluid velocity field in the wall appendage area. Efficiency recovery. On the basis of investigating the effects of inclination angle, water flow rate, feed concentration, feed rate and overflow flow rate on the recovery rate of coarse slime combustible, the inclination angle, water flow rate and feed concentration are determined as the main controllable factors. Three factors and three levels orthogonal test are designed and carried out with the help of orthogonal experimental design software. By means of scanning electrode analysis and X-ray fluorescence spectrometry, the material before and after separation is analyzed and tested. The results show that the variable diameter liquid-solid fluidized bed separation system can effectively realize the removal of coarse coal gangue and the efficient recovery of combustible materials. In this paper, the characteristics of overflow flow flow are discussed, and the application of fuzzy neural network control in overflow flow flow control is explored. For the non-linear and multi-variable variable diameter liquid-solid fluidized bed separation system, a dual-input and single-output adaptive fuzzy neural network control system is constructed. The control system is modeled and simulated by MATLAB/Simulink software. The simulation results show that the adaptive fuzzy neural network controller has faster response time and less overshoot than the fuzzy controller. This will improve the response ability and robustness of the control system and reduce the steady-state error.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD94
本文编号：2244306
[Abstract]:High efficient physical separation and recovery of coarse slime particles is of great significance for resource recycling and environmental protection. In this paper, coarse slime materials are selected as the research object, the macro-density and particle size composition of coarse slime materials are studied, and the data of density and particle size composition are obtained. The material samples were photographed before and after sorting, and the changes of one-dimensional and two-dimensional gray levels of coarse slime particles in micro-state were analyzed by JMicro Vision software. The properties of coarse slime particles and the Micro-changes of components of coarse slime before and after sorting were described intuitively. It is of great practical significance and application value to adopt a new type of variable diameter liquid-solid fluidized bed separation system to separate coarse coal slime. Based on the large density difference between coal and gangue particles in coarse coal slime materials, the separation of coarse coal slime materials is aimed at. A new type of modular variable-diameter liquid-solid fluidized bed separator was designed and a new type of structured variable-diameter liquid-solid fluidized bed separator was established, including modular design separator and supporting equipment. The main force of coarse slime particles in the variable-diameter liquid-solid fluidized bed separation system is determined by comparison, and the secondary force is neglected. The assumption that the drag coefficient of particles in the process of particle group movement is only related to the Reynolds number of fluid flow near the particles is proposed. Based on the hypothesis of local energy minimization equilibrium of particle agglomeration, the behavior of particle agglomeration in granular fluid system is analyzed and explained. The movement of particles and the change of flow field in the bed during the separation of coarse slime in a variable-diameter liquid-solid fluidized bed are studied by using FLUENT software coupled with EDEM. In order to solve the problem of particle aggregation on the wall, this chapter explores the addition of top water holes. The feasibility and validity of the top hole are verified by the influence of the top water on the flow field distribution in the variable diameter liquid-solid fluidized bed and the influence of the top water on the fluid velocity field in the wall appendage area. Efficiency recovery. On the basis of investigating the effects of inclination angle, water flow rate, feed concentration, feed rate and overflow flow rate on the recovery rate of coarse slime combustible, the inclination angle, water flow rate and feed concentration are determined as the main controllable factors. Three factors and three levels orthogonal test are designed and carried out with the help of orthogonal experimental design software. By means of scanning electrode analysis and X-ray fluorescence spectrometry, the material before and after separation is analyzed and tested. The results show that the variable diameter liquid-solid fluidized bed separation system can effectively realize the removal of coarse coal gangue and the efficient recovery of combustible materials. In this paper, the characteristics of overflow flow flow are discussed, and the application of fuzzy neural network control in overflow flow flow control is explored. For the non-linear and multi-variable variable diameter liquid-solid fluidized bed separation system, a dual-input and single-output adaptive fuzzy neural network control system is constructed. The control system is modeled and simulated by MATLAB/Simulink software. The simulation results show that the adaptive fuzzy neural network controller has faster response time and less overshoot than the fuzzy controller. This will improve the response ability and robustness of the control system and reduce the steady-state error.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD94
【参考文献】
相关期刊论文 前6条
1 王培铭;丰曙霞;刘贤萍;;背散射电子图像分析在水泥基材料微观结构研究中的应用[J];硅酸盐学报;2011年10期
2 石常省,王泽南,谢广元;煤泥分级浮选工艺的研究与实践[J];煤炭工程;2005年03期
3 M.W.米凯尔 ,李国森;螺旋分选机和水介质旋流器洗选粉煤的评价与应用[J];选煤技术;1991年01期
4 韩云;世界四座最大选煤厂[J];选煤技术;2002年04期
5 刘文礼;陈子彤;位革老;任桂飞;王学民;;干扰床分选机分选粗煤泥的规律研究[J];选煤技术;2007年04期
6 ;New progress in the processing and efficient utilization of coal[J];Mining Science and Technology;2011年04期
相关博士学位论文 前1条
1 王帅;电厂磨机返料在稀相振动气固流化床中的颗粒分离行为[D];中国矿业大学;2013年
，本文编号：2244306
本文链接：https://www.wllwen.com/kejilunwen/kuangye/2244306.html
