PR-186-133605-R01 Internal Corrosion Sample Collection Guidelines

Pipeline liquid and solid samples collected as a part of internal corrosion monitoring and other assessment activities are vulnerable to compositional changes resulting from sample handling procedures. These compositional changes can affect subsequent test results and the usefulness/accuracy of the data. Understanding the changes that occur due to sampling variables will help operators identify the significance of these changes to the test results.

A set of experiments performed in this study were able to demonstrate some effects of sample holding time, sample holding temperature, and sample container headspace on certain constituents (pH, dissolved CO2, dissolved H2S, alkalinity, culturable bacteria) typically measured during internal corrosion evaluations. The project also identified general considerations for establishing and implementing internal corrosion sampling programs, since other factors in addition to changes that occur during handling can affect the accuracy, quality, and utility of test results.

The deliverables of this project can be used directly by operators to assess their sampling programs and also provide a foundation from which a comprehensive best practice for sampling programs can be developed.