Exploring pipeline technology: digital sensors and leak detection

This week we continue our look at some of the cutting-edge technologies potentially available to the pipeline industry to aid in their commitment to pipeline safety and integrity.

Researchers at the University of Alberta are currently exploring the potential use of digital sensors for pipeline leak detection. Digital sensors have a more than 11-year history at the university, with sensor technology being developed for such practical uses as monitoring the health of an implant in a bone, measuring blood alcohol levels of drivers and monitoring the structural health of vital infrastructure like bridges.

Walied Moussa, an engineer and professor with U of A’s mechanical engineering department, is working to develop this existing technology into pipeline monitoring and leak detection tools. CEPA spoke to Moussa about his research and got an inside look at four wireless technologies and their possible use for the pipeline industry.

U of A sensor cell technology.

The first technology consists of tiny sensors placed at regular intervals along a structure, like a bridge or pipeline. The sensors wirelessly send out data about the structural health of the structure, including indicating areas of fatigue or imminent damage. This type of data is useful to the regular, routine pipeline integrity monitoring and maintenance done by the pipeline industry.

These sensors can be used in tandem with what Moussa calls a “smart membrane” that’s wrapped around a pipeline and has the ability to sense leaking fluid. To illustrate how this membrane works, he likens it to a “smart-skin” bandage used to cover up a cut finger.

“It’s like if you wrapped a person’s cut with a smart skin that can actually feel the blood coming out of the skin and then use it to detect the person’s pulse. If you wrap our smart membrane around a pipe and you put it on the ground, we’ll be able to detect any small leak and pinpoint exactly where this leak is using a wireless technology that we develop,” he explains.

The next digital sensor technology is used in the soil outside a pipeline. These sensors are used to detect healing in between bones and implants, as well as to detect blood-alcohol in drivers. In a similar fashion, this technology can detect the presence of hydrocarbons in soil. Moussa calls these sensors “crystal balls”. His idea is to insert them into the ground at regular intervals around an existing pipeline so that they sit about five inches outside the pipe. If a pipeline begins to leak, the sensors will detect it and wirelessly send data about the leak’s location to pipeline operators.

Finally, Moussa says he is researching the use of a “mini-pig”, a ball inserted into a pipeline that is equipped with sensors that detect changes to the inside of a pipe. These sensors are able to detect forces on a surface similar to how a tablet detects the force of your finger when you press on it. Each ball consists of many sensors and multiple balls can be used together to collect and corroborate data.

“These balls act like a police patrol. You can send out as many as you wish one after the other and they all talk to each other because they are wireless. The nodes talk to each other and if one of them finds something, and the next one coming by finds the same thing, then you know you have a problem and you know exactly where that problem is.”

Moussa says pipeline operators could potentially use these sensors individually or together as one system to aid their pipeline integrity efforts. His research continues and he anticipates the technology to be commercially available in three to five years.

The Canadian Energy Pipeline Association represents Canada’s transmission pipeline companies who operate approximately 110,000 kilometres of pipelines in Canada. In 2011, these energy highways moved approximately 1.2 billion barrels of liquid petroleum products and 5.3 trillion cubic feet of natural gas. Our members transport 97 per cent of Canada’s daily natural gas and onshore crude oil from producing regions to markets throughout North America.