Use of transmission gamma for study of calculation of incrustation thickness in oil pipelines

Abstract

Incrustation can be defined as chemical compounds organic, inorganic and mixed, initially insoluble, and which precipitate accumulating in the internal wall of pipes, surface equipment and/or parts of components involved in the production and transport of oil. These compounds, when precipitating, cause problems in the oil industry and consequently result in losses in the optimization of the extraction process. Although the importance and impact of the precipitation of these compounds in the technological and economic scope, there is still the difficulty in determining methods that enable the identification and quantification of the incrustation at an initial stage. The use of the gamma transmission technique may provide support for a better understanding of the deposition of these compounds, making it a suitable tool for the non-invasive determination of their deposition in oil transport pipelines. The geometry used for the incrustation detection include a 280 mm diameter steel pipe containing barium sulphide incrustation (BaSO4) ranging from 5 to 80 mm, a gamma radiation source with divergent beam and as NaI(Tl) 2x2” scintillation detector. The opening size of the collimated beam was evaluated (2 to 7 mm) to also quantify the associated error in calculating the incrustation. The study was realized with computer simulation, using the MCNP-X code and validated by means of analytical equations that indicate the possibility of using this study for this purpose