Investigation and non-destructive examinations of gas dehumidification heaters of a refinery unit, identifying and preventing damage mechanisms

Heaters play an important role in a gas refinery by increasing the process fluid temperature. In case of flammable fluid inside the tubes, inspection and condition monitoring is of great importance. In the present study, the condition of the gas dehumidification unit heaters of a gas refinery has been evaluated. In and out of service inspections including thermography, ocular inspection, ultrasonic thickness measurement, Replica metallography and surface temperature analysis of both convection and radiation part tubes were utilized. Thermography and online surface temperature data confirm thickness measurement results, indicating thickness of tubes were within the allowable range. However, a lot of sediment observed on radiation tube surface, probably because of Probably due to ambient air pollution, there were no microstructure changes and creep formation based on metallographic results. In a nutshell, no oxidation and no corrosion signs were observed on tubes even in formed sediments area.

Keywords:

gas dehumidification heater , gas refining , non-destructive examinations.