Pipeline Pig Decontamination
According to the United States Bureau of Transportation Statistics, there are more than 1,670,000 miles of oil and natural gas pipeline buried under US soil. America’s pipeline operators work continuously to provide safe, reliable and efficient delivery of product to their customers. If deterioration of the steel sidewalls of these pipelines is detected, proactive repairs must be made to maintain their integrity and assure that product continues to flow in a safe reliable manner.
For decades, the pipeline industry has used in-line inspection tools to aid in the detection of corrosion and to assist in determining its severity. Advancements in technology have contributed to the speed and accuracy by which this structural analysis can now be done. A device that travels inside the pipeline is commonly referred to as a “Pig”. Pigs match the inside diameter of a pipeline and are used for a variety of purposes including cleaning, product separation and inspection.
Intelligent or smart pigs, contain electronic components that collect data related to the integrity of the pipe walls. One of the most common methods is known as MFL or Magnetic Flux Leakage. The basic principal is that a powerful magnet is used to magnetize the steel. At areas where there is corrosion, or deteriorated metal, the magnetic field “leaks” from the pipe wall. In an MFL tool, a magnetic detector is placed between the poles of the magnet to measure the amount of leakage.1
The MFL tool (see picture) enters the pipeline through a specially designed launch tube and travels through the pipeline propelled by the pressure of the gaseous or liquid product in the line. As the tool moves along, the sophisticated electronics are recording critical information that will later be used to assess the condition of the pipe walls and allow the pipeline operator to make repairs prior to metal fatigue or failure.
The technicians at Bodine Environmental Services have significant experience in cleaning and decontaminating these very sophisticated, very expensive “Smart Pigs.” It is critical that proper cleaning and decon is accomplished so the pig is functioning reliably when it is placed back in service for another run.
The objective when cleaning a smart pig is to remove the residual pipeline material that remains on the pig, and to properly handle the wash waters and rinsates through to disposal. Although the cleaning protocol may differ somewhat based on the presence of PCB’s in the pipeline, the basic method consists of a pre-wash treatment using biodegradable detergents, followed by a multi-step wash and rinse process using high pressure hot water wash machines. In some cases, PCB testing is required once the process is complete.
Often, it is necessary to clean the interior of the pipeline prior to using the smart pigs. Failure to remove significant accumulations of material from the pipe walls could impact the accuracy or travel of the smart pig. Bodine also is experienced in pipeline cleaning using poly pigs. If you have a desire to discuss these or other Bodine capabilities, please contact us so one of our technical professionals can help you develop a cost effective solution to your cleaning challenges.
- Source: Wikipedia Encyclopedia