Oil and gas transported through pipelines over hundreds to thousands of miles are essential to the industries and the consumers who depend on them. With some of the longest pipelines, such as Nord Stream 2 stretching thousands of miles underwater, it's not uncommon for them to be clogged over time.
Considering that there have been only a few methods of identifying pipeline clogging in-situ and non-destructively, the revolutionary neutron-based clog detection method provides the best alternative.
According to the experiments done at the Research Neutron Source Heinz Maier-Leibnitz (FRM II) at the Technical University of Munich (TUM), neutrons gave impressive results that could provide the much-needed solution to pipeline clogging.
Previous Approaches Offer No Viable Solution for Underwater Pipeline Clogging
The first step in remediating pipeline clog is by locating the specific part of the pipe containing the clog. However, locating the exact position of the clog within a section of the pipe can be challenging.
Some of the most commonly used technology to identify clogs include gamma rays and thermal imaging cameras. Unfortunately, these techniques cannot be used to inspect underwater pipelines. While Ultra-sound can penetrate the water, detecting the hydrate blocks is only possible at proximity with the pipeline wall.
Considering that the underwater pipelines are always laid at a depth of about 2000 meters and usually covered by the materials at the seabed such as silt, sand, and other debris, the constrain poses even more practical difficulties in using these techniques to identify clogs in underwater pipes.
In addition, acoustic methods could also result in improper discrimination due to unclear differences between the hydrate phases of the crude oil and acoustic impedances.
Neutrons—the Perfect Solution for Clog Detection
TechnipFMC, a giant company specializing in subsea pipelines, is "looking for a more efficient method to find the plugs in a non-contact, non-destructive and reliable way despite thick walls," said the company's project manager Dr. Xavier Sebastian.
Dr. Sophie Bouat, CEO of Science-S.A.V.E.D. (Scientific Analysis Vitalises Enterprise Development) also suggested that "neutrons are the perfect probe for the task at hand."
"Using prompt gamma neutron activation analysis, light atoms and hydrogen, in particular, can be detected very precisely," she added.
Since normal gas or oil has considerably different hydrogen to hydrates, blockades can be easily detected by measuring hydrogen concentration.
According to Dr. Ralph Gilles, industry coordinator at the Research Neutron Source FRM II, the results empirically show neutrons are suitable for the task.
"Our experiments have shown that we can even distinguish an incipient blockage from a fully developed one," said Dr. Ralph Gilles. "That's very beneficial because then one can even preventatively heat a pipe segment to melt the blockage before it fully develops," he added. Designed with a small neutron source moves.
In a typical scenario, a mobile detector can move back and forth along the oil or gas pipeline to detect the clogs.
"We are very pleased that, with the help of the measurements at the research neutron source, we have now found an efficient method that makes it much easier to detect these plugs in the future," said Dr. Xavier Sebastian.