空化处理油酸钠体系一水硬铝石聚团行为  

Aggregation of fine diaspore particles in sodium oleate solutions pretreated by hydrodynamic cavitation

作　　者：周伟光 刘欣然[1,2] 王森 欧乐明[3] ZHOU Wei-guang;LIU Xin-ran;WANG Sen;OU Le-ming(Key Laboratory of Coal Processing and Efficient Utilization(Ministry of Education),China University of Mining and Technology,Xuzhou 221116,China;School of Chemical Engineering and Technology,China University of Mining and Technology,Xuzhou 221116,China;School of Resource Processing and Bioengineering,Central South University,Changsha 410000,China)

机构地区：[1]中国矿业大学煤炭加工与高效洁净利用教育部重点实验室,徐州221116 [2]中国矿业大学化工学院,徐州221116 [3]中南大学资源加工与生物工程学院,长沙410000

出　　处：《中国有色金属学报》2023年第12期4237-4253,共17页The Chinese Journal of Nonferrous Metals

基　　金：国家自然科学基金资助项目(52104280);中央高校基本科研专项基金资助项目(2021QN1043)。

摘　　要：通过小角激光散射法研究了空化处理(HC)油酸钠体系一水硬铝石聚团行为。结果表明:短时间(<15 min)空化处理没有改变油酸钠化学性质,但导致了纳米气泡的生成;絮体粒径随油酸钠浓度、空化强度、空化时间的增加而逐渐增大,随搅拌转速、搅拌时间的增加而先减小后增大,最大为31.278μm,最小为15.628μm;絮体质量分形维数随油酸钠浓度、搅拌转速、搅拌时间的增加而先增大后减小,随空化强度、空化时间的增加而逐渐减小,最大为1.912,最小为1.692;空化处理油酸钠溶液没有改变絮体性质总体变化规律,但导致絮体粒径相对增大、质量分形维数相对减小;空化溶液中纳米气泡桥联诱导形成大而松散的絮体,促使颗粒聚集过程向有限扩散集团凝聚转变。总体而言,纳米气泡越多,絮体性质变化越明显。The effect of hydrodynamic cavitation(HC) pretreatment of sodium oleate(NaOl) solutions on the aggregation of fine diaspore particles in a stirring system was studied by small angle laser scattering method.The results show that a short-time(i.e.,<15 min) HC pretreatment cannot significantly alter the chemical properties of NaOl,but result in the formation of nanobubbles(NBs) in solutions.During the shear flocculation,the floc size increases gradually with the increase of NaOl concentration,cavitation intensity,cavitation time,and decreases first and then increases with the increase of stirring speed and stirring time,with the maximum value being 31.278μm and the minimum valve being 15.628 μm in the whole measurements.Also,the mass fractal dimension of floc first increases and then decreases with the increase of NaOl concentration,stirring speed and stirring time,and gradually decreases with the increase of cavitation intensity and time,with the maximum of 1.912 and the minimum of 1.692.Furthermore,there is no significant change in the overall evolution of floc characteristics under fixed variables regardless of HC pretreatment or not,only leading to a relative increase in floc size and a relative decrease in mass fractal dimension in the presence of HC pretreatment.This is because NBs generated during the HC process benefit the formation of large and loose flocs via the capillary bridging,which therefore accelerates the flocculation process close to the diffusion-limited cluster aggregation.Generally,as the concentration of NBs increases in aqueous solutions,the noticeable alterations in floc characteristics become more pronounced.

关 键 词：水力空化 纳米气泡 小角激光散射法 分形维数 一水硬铝石 

分 类 号：TD91[矿业工程—选矿]