Drop formation at nozzles submerged in quiescent continuous phase： an experimental study with TBP-dodecane and nitric acid system  

作　　者：Amitava Roy MayurDarekar K. K. Singh K. T. Shenoy R. B. Grover 

机构地区：[1]Homi Bhabha National Institute,Anushaktinagar, Mumbai 400094, India [2]Chemical Engineering Division, Bhabha Atomic Research Centre, Mumbai 400085, India

出　　处：《Nuclear Science and Techniques》2018年第6期110-118,共9页核技术（英文）

摘　　要：Solvent extraction is an important process in the nuclear fuel cycle. Tributyl phosphate(TBP) diluted with dodecane is commonly used as a solvent for extracting heavy metals from nitric acid medium. Studies on hydrodynamics of a single drop, which is the smallest mass transfer entity, are required for better understanding of the complex mass transfer and phase separation phenomena that occur in extraction equipment. In this study, drop formation at nozzles is studied using 30% TBP-dodecane as the dispersed phase and dilute nitric acid as the quiescent continuous phase. Experiments are carried out to determine the drop diameter, jetting velocity, drop detachment height and drop detachment time for various dispersed phase velocities, nozzle diameters(1.91, 3.04, and 4.88 mm), and nitric acid concentrations(0.01, 1, 3 N). Drop formation is captured using high-speed imaging, which enables quantification of drop size, onset of jetting, drop detachment height, and drop detachment time. Experimental data are used to propose correlations for predicting drop diameter and minimum jetting velocity. The correlations are found to be very accurate with average absolute relative errors being 5.23 and 2.97%, respectively.Solvent extraction is an important process in the nuclear fuel cycle. Tributyl phosphate （TBP） diluted with dodecane is commonly used as a solvent for extracting heavy metals from nitric acid medium. Studies on hydro- dynamics of a single drop, which is the smallest mass transfer entity, axe required for better understanding of the complex mass transfer and phase separation phenomena that occur in extraction equipment. In this study, drop formation at nozzles is studied using 30% TBP-dodecane as the dispersed phase and dilute nitric acid as the quiescent continuous phase. Experiments are carried out to determine the drop diameter, jetting velocity, drop detachment height and drop detachment time for various dispersed phase velocities, nozzle diameters （1.91, 3.04, and 4.88 mm）, and nitric acid concentrations （0.01, 1, 3 N）. Drop formation is captured using high-speed imaging, which enables quan- tification of drop size, onset of jetting, drop detachment height, and drop detachment time. Experimental data are used to propose correlations for predicting drop diameter and minimum jetting velocity. The correlations axe found to be very accurate with average absolute relative errors being 5.23 and 2.97%, respectively.

关 键 词：试验性 硝酸 静止 沉没 系统 高速度 分离现象 磷酸盐 

分 类 号：TL249[核科学技术—核燃料循环与材料]