Radioactive particle tracking

Radioactive particle tracking (RPT) can be used to map the velocity field by tracking the position of a single radioactive tracer particle in a reactor. The particle which may consist of a polypropylene shell contains a radionuclide that emits y-rays. 

Direct measurement of particle velocity and velocity fluctuations in fluidized beds or riser reactors is necessary for validating multiphase models. Dudukovic [14] and Roy and Dudukovic [28] have used computer-automated radioactive particle tracking (CARPT) to foUow particles in a riser reactor. From their measurements, it was possible to calculate axial and radial solids diffusion as well as the granular temperature from a multiphase KTGF model. Figure 15.10 shows one such measurement... 

J. Chen, R. Novica, M.H. Al-Dahhan, M.P. Dudukovic, Study of particle motion in packed/ebullated beds by computed tomography (CT) and computer automated radioactive particle tracking (CARPT), AIChE J. 47 (5) (2000) 994-1004. 

Larachi et al. (1996) applied their radioactive particle tracking technique to determine the time-averaged solids velocity in a three-phase fluidized bed. Techniques which are similar to CARPT, such as positron emission particle tracking and radioactive particle tracking, have been applied successfully to systems involving particulate solids. 

The fluidized bed systems have been utilized extensively in many physical, chemical, petrochemical, electrochemical, and biochemical processes. Successful applications of the fluidization systems lie in a comprehensive understanding of hydrodynamics, heat and mass transfer properties, and mixing. Various non-intrusive measurement techniques, such as electric capacitance tomography and radioactive particle tracking technique, are available to advance the fundamental understanding of the microscopic and macroscopic phenomena of fluidization. Till date, the... 

Lin JS, Chen MM, Chao BT (1985) A Novel Radioactive Particle Tracking Facility for Measurement of Solids Motion in Gas Fluidized Beds. AIChE J 31(3) 465-473... 

In the radioactive-particle tracking methodology, the distance is inferred by measuring the scintillation rate n. Thus, the approximate relationship between the accuracy of the distance measurement and the scintillation rate from Eq. 9.20 is... 

Sun, J. G., 1985, Data Processing Problems for Radioactive Particle Tracking Measurement, M. S. Thesis, Univ. of Illinois, Urbana-Champaign. 

Sun, J. G., Chen, M. M., and Chao, B. T., 1990, Radioactive Particle Tracking Measurement of the Mean Particulate Stress in a Fluidized Bed, paper presented at AIChE. Winter Annual Meeting, Chicago, Nov. 11-15, 1990. 

The velocity and hold-up distribution of the solid phase in a liquid-solid riser has been studied with radioactive particle tracking and computed tomography (CT).[ 1 The goal of this research was the development of an understanding of the variables affecting the performance of liquid-solid risers, and of fundamentally-based scale-up rules. An improved PEPT system has recently been developed, capable of continuously following the 3D trajectory of a radiotracer particle (as small as 500/um) moving at 0.1 ms with a resolution of 5 mm. The system has been used to measure in situ flow patterns of solids in a gas-solids Interconnected Fluidised Bed reactor. 

Computer-automated radioactive particle tracking (CARPT) (Cassanello et al. 

Fraguio MS, Casanello MC, Degaleesan S, Dudukovic MR (2009) Flow regime diagnosis in buhhle columns via pressure fluctuations and computer-assisted radioactive particle tracking measurements. Ind. Eng. Chem. Res., 48 1072-1080. 

To properly test the flow pattern in the cold flow model of the riser (Fig. 1.6 Roy, 2000), a conventional tracer study was first conducted that showed the Hquid was essentiaHy in plug-flow with a RTD equivalent to greater than about 20 tanks-in-series for the given operating conditions. The Computer Automated Radioactive Particle Tracking (CARPT) faciHty in CREL was used to determine the soHds flow pattern in the riser, and the... 

Recently, a novel hybrid radioactive particle tracking (RPT) facility has been developed where the calibration step for the radioactive particle was eliminated (Khane and Al-Dahhan, 2013). The new technique is claimed to minimize the dynamic bias associated with the original CARPT... 

Rammohan AR, Kemoim A, Al-Dahhan MH, Dudukovic MP A Lagrangian description of flows in stirred tanks via computer-automated radioactive particle tracking (CARPT), Chem Eng Sci 56 2629-2639, 2001a. http //dx.doi.org/10.1016/S0009-2509(00)00537-6. 

Chen JAK, Al-Dahhan Muthanna H, Dudukovic Milorad P, Lee DJ, Fan LS Comparative hydrodynamics study in a bubble column using computer-automated radioactive particle tracking (CARPT)/computed tomography (CT) and particle image velocimetry (PIV), Chem Eng Sd 54 2199-2207, 1999. 

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