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工程科学学报,第41卷,第8期:987-996,2019年8月 Chinese Journal of Engineering,Vol.41,No.8:987-996,August 2019 DOI:10.13374/j.issn2095-9389.2019.08.004;http://journals.ustb.edu.cn 剪切浓密床层孔隙网络模型与导水通道演化 焦华喆”,王树飞),吴爱祥),沈慧明),杨亦轩3)四,阮竹恩2) 1)河南理工大学土木工程学院,焦作4540002)北京科技大学土木与资源工程学院,北京100083 3)河南理工大学资源环境学院.焦作454000 ☒通信作者,E-mail:yangyixuan@hpu.edu.cm 摘要剪切作用是膏体重力浓密制备的基础要素,本文研究了浓密床层孔隙和喉道的变化对导水通道的影响,揭示了水分 排出的来源与比例.开展半工业实验并结合计算机断层扫描(CT)与孔隙网络模型(PNM)提取床层微观孔隙结构,利用最大 球搜索算法识别并分析剪切前后孔隙与喉道的演化规律.结果表明,添加转速为2r·mi'的剪切作用将尾砂底流浓度(即底 流的固相质量分数)由55.8%提升到58.5%,孔隙率由43.05%降低到36.59%,孔隙率降低的比率为15%.通过PNM技术将 孔隙空间划分为“球体”储水孔隙与“棍体”喉道:剪切后球体和棍体数量分别增加了16.5%和22%,球体平均尺寸小幅下降, 球体半径多集中在40-60μm之间.棍体平均半径由9.83μm降低至8.58μm,降低了12.7%,棍体长度变化较小.剪切作用 下的球体配位数在5~10的部分从25.73%增加至44.58%,配位明显增多,颗粒接触紧密.本文提出“球棍比”的概念用于孔 隙结构的定量表征.剪切后球体体积占比由14.14%降低至12.75%,球体体积减少的比率达到9.83%:棍的体积由28.91% 降低至23.84%,棍体积减少的比率为17.54%.球棍比由48.91%增加至53.48%,球棍比提升的比率达到了9.34%,与球体 体积减小相比,棍的体积减少的幅度更大,导致球棍比上升.本文从孔隙结构变化的角度揭示了全尾砂重力浓密剪切排水机 理:剪排水过程中主要排出的是喉道中的水分,孔隙中的水分排出较少 关键词膏体充填;重力浓密:剪切作用:孔隙率:导水通道:球棍比 分类号TD853 Pore network model of tailings thickener bed and water drainage channel evolution under the shearing effect JIAO Hua-zhe,WANG Shu-fei,WU Ai-xiang?),SHEN Hui-ming?),YANG Yi-xuan,RUAN Zhu-en2) 1)School of Civil Engineering,Henan Polytechnic University,Jiaozuo 454000,China 2)School of Civil and Resources Engineering,University of Science and Technology Beijing,Beijing 100083.China 3)School of Resources and Environment,Henan Polytechnic University,Jiaozuo 454000,China Corresponding author,E-mail:yangyixuan@hpu.edu.cn ABSTRACT Shearing is the basic factor involved in gravity thickening of paste.This work focuses on the influence of pores and throats characteristics on water drainage channel evolution,and determines the proportion of discharged water in tailings thickener bed. Pilot-scale experiment combined with computed tomography (CT)and pore network model (PNM)technology to determine the micro- pore structure.The maximum ball algorithm is used to analyze the evolution of pores and throats with and without shearing.The results show that the tailings underflow concentration increases from 55.8%to 58.5%under 2rmin rake shearing and the porosity decrea- ses from 43.05%to 36.59%,the decrease rate of porosity is 15%.The pore structure can be divided into two types,i.e.,"balls" and "sticks,"by the PNM technology.The quantity of "balls"and "sticks"increases by 16.5%and 22%,respectively.However, 收稿日期:2018-10-03 基金项目:国家自然科学基金资助项目(51704094,51834001,51574013):河南省高等学校重点科研项目(16A440003):国家安全生产重大事 故防治关键技术项目(henan-0005-2016AQ)工程科学学报,第 41 卷,第 8 期:987鄄鄄996,2019 年 8 月 Chinese Journal of Engineering, Vol. 41, No. 8: 987鄄鄄996, August 2019 DOI: 10. 13374 / j. issn2095鄄鄄9389. 2019. 08. 004; http: / / journals. ustb. edu. cn 剪切浓密床层孔隙网络模型与导水通道演化 焦华喆1) , 王树飞1) , 吴爱祥2) , 沈慧明2) , 杨亦轩3) 苣 , 阮竹恩2) 1)河南理工大学土木工程学院, 焦作 454000 2)北京科技大学土木与资源工程学院, 北京 100083 3)河南理工大学资源环境学院, 焦作 454000 苣通信作者, E鄄mail: yangyixuan@ hpu. edu. cn 摘 要 剪切作用是膏体重力浓密制备的基础要素,本文研究了浓密床层孔隙和喉道的变化对导水通道的影响,揭示了水分 排出的来源与比例. 开展半工业实验并结合计算机断层扫描(CT)与孔隙网络模型(PNM)提取床层微观孔隙结构,利用最大 球搜索算法识别并分析剪切前后孔隙与喉道的演化规律. 结果表明,添加转速为 2 r·min - 1的剪切作用将尾砂底流浓度(即底 流的固相质量分数)由55郾 8% 提升到58郾 5% ,孔隙率由43郾 05% 降低到36郾 59% ,孔隙率降低的比率为15% . 通过 PNM 技术将 孔隙空间划分为“球体冶储水孔隙与“棍体冶喉道;剪切后球体和棍体数量分别增加了 16郾 5% 和 22% ,球体平均尺寸小幅下降, 球体半径多集中在 40 ~ 60 滋m 之间. 棍体平均半径由 9郾 83 滋m 降低至 8郾 58 滋m,降低了 12郾 7% ,棍体长度变化较小. 剪切作用 下的球体配位数在 5 ~ 10 的部分从 25郾 73% 增加至 44郾 58% ,配位明显增多,颗粒接触紧密. 本文提出“球棍比冶的概念用于孔 隙结构的定量表征. 剪切后球体体积占比由 14郾 14% 降低至 12郾 75% ,球体体积减少的比率达到 9郾 83% ;棍的体积由 28郾 91% 降低至 23郾 84% ,棍体积减少的比率为 17郾 54% . 球棍比由 48郾 91% 增加至 53郾 48% ,球棍比提升的比率达到了 9郾 34% ,与球体 体积减小相比,棍的体积减少的幅度更大,导致球棍比上升. 本文从孔隙结构变化的角度揭示了全尾砂重力浓密剪切排水机 理;剪排水过程中主要排出的是喉道中的水分,孔隙中的水分排出较少. 关键词 膏体充填; 重力浓密; 剪切作用; 孔隙率; 导水通道; 球棍比 分类号 TD853 收稿日期: 2018鄄鄄10鄄鄄03 基金项目: 国家自然科学基金资助项目(51704094, 51834001, 51574013); 河南省高等学校重点科研项目(16A440003); 国家安全生产重大事 故防治关键技术项目(henan鄄鄄0005鄄鄄2016AQ) Pore network model of tailings thickener bed and water drainage channel evolution under the shearing effect JIAO Hua鄄zhe 1) , WANG Shu鄄fei 1) , WU Ai鄄xiang 2) , SHEN Hui鄄ming 2) , YANG Yi鄄xuan 3) 苣 , RUAN Zhu鄄en 2) 1) School of Civil Engineering, Henan Polytechnic University, Jiaozuo 454000, China 2) School of Civil and Resources Engineering, University of Science and Technology Beijing, Beijing 100083, China 3) School of Resources and Environment, Henan Polytechnic University, Jiaozuo 454000, China 苣Corresponding author, E鄄mail: yangyixuan@ hpu. edu. cn ABSTRACT Shearing is the basic factor involved in gravity thickening of paste. This work focuses on the influence of pores and throats characteristics on water drainage channel evolution, and determines the proportion of discharged water in tailings thickener bed. Pilot鄄scale experiment combined with computed tomography (CT) and pore network model (PNM) technology to determine the micro鄄 pore structure. The maximum ball algorithm is used to analyze the evolution of pores and throats with and without shearing. The results show that the tailings underflow concentration increases from 55郾 8% to 58郾 5% under 2 r·min - 1 rake shearing and the porosity decrea鄄 ses from 43郾 05% to 36郾 59% , the decrease rate of porosity is 15% . The pore structure can be divided into two types, i. e. , “balls冶 and “sticks,冶 by the PNM technology. The quantity of “balls冶 and “sticks冶 increases by 16郾 5% and 22% , respectively. However
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