液固流化床分选机理研究
|
摘要
本文采用理论结合试验的方法探究了液固流化床分选机理。得到了液固流化床分选机内自生介质流化床层性质。以不同粒度石英砂为自生介质颗粒,研究了自生介质粒度对分选效果的影响。研究发现,自生介质粒度越细,能实现的分选效果越好。其中,0.15～0.20 mm石英砂床层的最小E_p值为0.053;0.25～0.45 mm石英砂床层能达到的最小E_p值增大到0.095。通过分析入料粒度分布和操作条件对分选效率的影响,认为控制入料粒度应从入料粒度范围和入料粒度下限两方面考虑。在某一床层压力设定值下,保持较小的上升水流速率,可减小粒度和形状对颗粒运动的影响,有利于床层维持较高的颗粒体积分数和有效密度,可提高分选效果。
Separation mechanism of liquid-solid fluidized bed separator(LSFBS) was studied by using theoretical analysis and experimental researches.Characteristics of autogenous medium fluidized bed in LSFBS were analyzed and the influence of autogenous medium size on the separation performance of LSFBS was studied,taking quartz particles of various sizes as autogenous medium.According to the separation results,a better segregation could be achieved by using finer autogenous medium.Particularly,the optimum of E_p value of 0.15～0.2 mm quartz was 0.053 while that of 0.25～0.45 mm quartz increased to 0.095.Finally,the influence of size distribution of feed and operating conditions on the separation efficiency was analyzed.Reducing feed size range and enlarging lower-size limit of feed could improve the device performance.Under a certain bed pressure,a smaller upward current velocity could generate a higher solid volume fraction and bed effective density.A smaller upward current velocity could also decrease the influence of size and shape on the movement of particles.All of these changes could induce a better separation performance for LSFBS.
Separation mechanism of liquid-solid fluidized bed separator(LSFBS) was studied by using theoretical analysis and experimental researches.Characteristics of autogenous medium fluidized bed in LSFBS were analyzed and the influence of autogenous medium size on the separation performance of LSFBS was studied,taking quartz particles of various sizes as autogenous medium.According to the separation results,a better segregation could be achieved by using finer autogenous medium.Particularly,the optimum of E_p value of 0.15～0.2 mm quartz was 0.053 while that of 0.25～0.45 mm quartz increased to 0.095.Finally,the influence of size distribution of feed and operating conditions on the separation efficiency was analyzed.Reducing feed size range and enlarging lower-size limit of feed could improve the device performance.Under a certain bed pressure,a smaller upward current velocity could generate a higher solid volume fraction and bed effective density.A smaller upward current velocity could also decrease the influence of size and shape on the movement of particles.All of these changes could induce a better separation performance for LSFBS.
引文
[1] Epstein N.Teetering[J]. Powder Technology,2005,151(1/3):2-14.
[2] Yang W C.Handbook of fluidization and fluid-particle systems[J]. China Particuology,2003,1(3):137-137.
[3] 骆振福.流态化分选理论[M]. 徐州:中国矿业大学出版社,2002.
[4] 任才富,王栋民,郑大鹏,等.掺超细循环流化床粉煤灰的水泥性能试验研究[J]. 矿业科学学报,2016,1(1):96-102. Ren Caifu,Wang Dongmin,Zheng Dapeng,et al. Study on properties of cement mixed with ultrafine circulating fluidized bed fly ash[J]. Journal of Mining Science and Technology,2016,1(1):96-102.
[5] 骆振福,陈清如.气固流态化技术在矿物分选的应用[J]. 金属矿山,1999(7):28-31. Luo Zhenfu,Chen Qingru.Application of gas-solid fluidization technology in mineral processing[J]. Metal Mine,1999(7):28-31.
[6] Honaker R Q,Mondal K.Dynamic modeling of fine coal separations in a hindered-bed classifier[J]. Coal Preparation,2000,21(2):211-232.
[7] Kim B H.Modeling of hindered-settling column separations[D]. Borough of State College:Department of Energy and Geo-Environmental Engineering,The Pennsylvania State University,2003.
[8] Xia Y.Numerical simulation of fine particle separation in hindered-settling bed separators by computational fluid dynamics[D]. Morgantown:College of Engineering and Mineral Resources,West Virginia University,2004.
[9] 舒长河,张小平,梁翾翾.液-固流化床回收印刷线路板中金属的研究[J]. 环境工程学报,2009,3(5):902-906. Shu Changhe,Zhang Xiaoping,Liang Xuanxuan.Study on recovery of metals from printed circuit board using a solid-liquid fluidized bed[J]. Chinese Journal of Environmental Engineering,2009,3(5):902-906.
[10] 段晨龙,赵跃民,伍玲玲,等.充气式液固流化床分选废弃电路板的实验研究[J]. 中国矿业大学学报,2014,43(5):915-919. Duan Chenlong,Zhao Yuemin,Wu Lingling,et al. Research on separation of waste printed circuit boards by an inflatable liquid-solid fluidized bed[J]. Journal of China University of Mining & Technology,2014,43(5):915-919.
[11] Kumar C R,Mohanan S,Tripathy S K,et al. Prediction of process input interactions of floatex density separator performance for separating medium density particles[J]. International Journal of Mineral Processing,2011,100(3/4):136-141.
[12] Tripathy S K,Murthy Y R,Singh V.Characterisation and separation studies of Indian chromite beneficiation plant tailing[J]. International Journal of Mineral Processing,2013,122:47-53.
[13] 王魁珽,刘金山,孙宁磊.固固分离装置:中国,CN101837318B[P]. 2010-04-23.
[14] Geldart D.The effect of particle size and size distribution on the behavior of gas fluidized beds[J]. Powder Technology,1972,6(4):201-215.
[15] Galvin K P,Pratten S,Nguyen T L G.A generalized empirical description for particle slip velocities in liquid fluidized beds[J]. Chemical Engineering Science,1999,54(8):1045-1052.
[16] 谢广元.选矿学[M]. 徐州:中国矿业大学出版社,2001.
[17] Galvin K P,Pratten S J,Nicol S K.Dense medium separation using a teetered bed separator[J]. Minerals Engineering,1999,12(9):1059-1081.
[18] 卢寿慈.矿物颗粒分选工程[M]. 北京:冶金工业出版社,1990.
[19] 王淀佐.资源加工学[M]. 北京:科学出版社,2005.
[20] Wei L,Sun M.Numerical studies of the influence of particles' size distribution characteristics on the gravity separation performance of liquid-solid fluidized bed separator[J]. International Journal of Mineral Processing,2016,157:111-119.
[2] Yang W C.Handbook of fluidization and fluid-particle systems[J]. China Particuology,2003,1(3):137-137.
[3] 骆振福.流态化分选理论[M]. 徐州:中国矿业大学出版社,2002.
[4] 任才富,王栋民,郑大鹏,等.掺超细循环流化床粉煤灰的水泥性能试验研究[J]. 矿业科学学报,2016,1(1):96-102. Ren Caifu,Wang Dongmin,Zheng Dapeng,et al. Study on properties of cement mixed with ultrafine circulating fluidized bed fly ash[J]. Journal of Mining Science and Technology,2016,1(1):96-102.
[5] 骆振福,陈清如.气固流态化技术在矿物分选的应用[J]. 金属矿山,1999(7):28-31. Luo Zhenfu,Chen Qingru.Application of gas-solid fluidization technology in mineral processing[J]. Metal Mine,1999(7):28-31.
[6] Honaker R Q,Mondal K.Dynamic modeling of fine coal separations in a hindered-bed classifier[J]. Coal Preparation,2000,21(2):211-232.
[7] Kim B H.Modeling of hindered-settling column separations[D]. Borough of State College:Department of Energy and Geo-Environmental Engineering,The Pennsylvania State University,2003.
[8] Xia Y.Numerical simulation of fine particle separation in hindered-settling bed separators by computational fluid dynamics[D]. Morgantown:College of Engineering and Mineral Resources,West Virginia University,2004.
[9] 舒长河,张小平,梁翾翾.液-固流化床回收印刷线路板中金属的研究[J]. 环境工程学报,2009,3(5):902-906. Shu Changhe,Zhang Xiaoping,Liang Xuanxuan.Study on recovery of metals from printed circuit board using a solid-liquid fluidized bed[J]. Chinese Journal of Environmental Engineering,2009,3(5):902-906.
[10] 段晨龙,赵跃民,伍玲玲,等.充气式液固流化床分选废弃电路板的实验研究[J]. 中国矿业大学学报,2014,43(5):915-919. Duan Chenlong,Zhao Yuemin,Wu Lingling,et al. Research on separation of waste printed circuit boards by an inflatable liquid-solid fluidized bed[J]. Journal of China University of Mining & Technology,2014,43(5):915-919.
[11] Kumar C R,Mohanan S,Tripathy S K,et al. Prediction of process input interactions of floatex density separator performance for separating medium density particles[J]. International Journal of Mineral Processing,2011,100(3/4):136-141.
[12] Tripathy S K,Murthy Y R,Singh V.Characterisation and separation studies of Indian chromite beneficiation plant tailing[J]. International Journal of Mineral Processing,2013,122:47-53.
[13] 王魁珽,刘金山,孙宁磊.固固分离装置:中国,CN101837318B[P]. 2010-04-23.
[14] Geldart D.The effect of particle size and size distribution on the behavior of gas fluidized beds[J]. Powder Technology,1972,6(4):201-215.
[15] Galvin K P,Pratten S,Nguyen T L G.A generalized empirical description for particle slip velocities in liquid fluidized beds[J]. Chemical Engineering Science,1999,54(8):1045-1052.
[16] 谢广元.选矿学[M]. 徐州:中国矿业大学出版社,2001.
[17] Galvin K P,Pratten S J,Nicol S K.Dense medium separation using a teetered bed separator[J]. Minerals Engineering,1999,12(9):1059-1081.
[18] 卢寿慈.矿物颗粒分选工程[M]. 北京:冶金工业出版社,1990.
[19] 王淀佐.资源加工学[M]. 北京:科学出版社,2005.
[20] Wei L,Sun M.Numerical studies of the influence of particles' size distribution characteristics on the gravity separation performance of liquid-solid fluidized bed separator[J]. International Journal of Mineral Processing,2016,157:111-119.