Positron emission particle tracking: A powerful technique for flow studies

Abstract

Positron emission particle tracking (PEPT) has developed into a flexible applied nuclear technique for measuring the trajectory of a single tracer particle moving in a system of granular or liquid flow or attached to a moving rigid body. The tracer particle is labelled with a radionuclide (such as 18 F or 68 Ga) that decays via positron emission. The nearly collinear 511 keV annihilation gamma rays are detected in coincidence by a modified positron emission tomography (PET) camera, which defines their line of response (LOR). The chronologically measured LORs may then be used to triangulate the position of the moving tracer particle. We present an introduction to PEPT and illustrate the quality of measurements possible with a high-resolution PET scanner. Data are presented and discussed with reference to a few fundamental measurement scenarios and a framework for the metrology of PEPT is introduced.

Standard method for performing positron emission particle tracking (PEPT) measurements of froth flotation at PEPT Cape Town

“…The PEPT experiments are performed at the laboratories of PEPT Cape Town, which houses an ECAT `EXACT3D' HR++ (Model: CTI/Siemens 966) PET camera [2] . The vessel is installed in the centre of the field of view of the positron camera via two truck trolleys and a supporting frame as shown in Fig.…”

Hydrodynamic characterisation of flotation impeller designs using Positron Emission Particle Tracking (PEPT)

“…The PEPT experiments were conducted at the PEPT Cape Town facility, situated within the iThemba LABS (South Africa). The Positron Emission Tomography (PET) camera used was a Siemens HR++ (shown in Figure 4), which is known for its high efficiency and large field of view (Buffler et al, 2018).…”

Fast γ Photon Imaging for Inner Surface Defects Detecting

“…After the labelled industrial object is scanned by the gamma photon detector, the LORs related to the inner radionuclide concentration distributions are obtained and stored in sinograms. An LOR is a pair of two 180-degree γ photons that meet the 511 KeV energy window and a certain time window [13,14]. Billions of LORs (depending on scanning time) saved in a group of parallel sinograms are recombined and reconstructed into tomographic images.…”