Determination of wax deposition and corrosion in pipelines by neutron back diffusion collimation and neutron capture gamma rays

Wax deposition in pipelines can be very costly for plant operation in oil industry. New techniques are needed for allocation and thickness determination of wax deposits. The timely removal of wax can make large saving in operational cost. Neutron back diffusion and neutron capture gamma rays were used in this study to measure paraffin, asphalt and polyethylene deposition thicknesses inside pipes and to enable simultaneous determination of scale and pipe corrosion. It was possible to determine a thickness change of less than one mm in 2 min. It was also possible to detect localized scale from a small region of the pipe of approximately 2 cm in diameter. Although experiments were performed in lab, the system can be made portable for field applications. (C) 2013 Elsevier Ltd. All rights reserved.