Abstract

• Radioisotope Techniques have been used as diagnostic tools in various industrial sectors to improve production efficiency and to gain information that cannot be obtained in any other way. The gamma ray computed tomography (CT) is a radioisotope technique largely used for troubleshooting and optimization of the industrial process plants. The experimental research to investigate the interior distribution of density of the different density materials and the phase distribution inside the multiphase system have been carried out using GORBIT - the first generation gamma CT system at the Radioisotope Techniques Laboratory in the Division of Atomic Energy. The GORBIT CT system consists of one collimated radioactive source, one collimated detector, a radiation rate-meter, two servo motors and an electronic control system. The associated GORBIT software was used for controlling the hardware's operations and logging data. The objects were located in the middle of the gantry. The data were collected by measuring the radiation emitted from the radiation source moving around the objects. The radiation source was 50mCi of Co-60 gamma source and the detector was a 2″ × 2″ NaI (TI) gamma scintillation detector. Tomography images were reconstructed from the acquired gamma transmission data by Filter Back Projection (FBP) algorithm using the separate GORBIT software. The experimental results of two dimensional CT images interpreted the cross sectional profiles of the objects and multiphase system and also provided information on the internal structure of the objects including defects and their dimensions. Therefore the gamma computed tomography (CT) has proved a powerful non destructive testing and evaluation tool and has wide range of applications in the petrochemical and chemical process industries: distillation columns, packed beds, risers, fluidized beds and other multiphase processing units.