Development of a SPECT System for Industrial Process Flow Measurement Using Diverging Collimators

In industrial processes where multiphase flows are frequently encountered, it is important to examine the phase distribution and flow pattern to optimize process efficiency, safe operation, and cost savings. One of the most suitable techniques of industrial-process flow-dynamics visualization is the single photon emission computed tomography (SPECT) system, which provides, by means of a process-system-injected radioisotope source, cross-sectional images of the process flow. Obtaining reliable SPECT imaging results for a multiphase flow system, however, remains a significant challenge. In the present study, the use of a diverging collimator for improvement of industrial SPECT system performance is proposed. The advantages of the diverging-collimation industrial SPECT system as compared with a previous parallel-collimation version can be summarized as follows: (a) significant reduction of edge artifacts on a detection-efficiency map, and 19% improvement of average detection efficiency; (b) 36% improvement of image resolution; (c) accurate source region reconstruction even with the source positioned farther from the object’s center; and (d) a reduced system size.