Pipelines move millions of barrels of petroleum products around North America in any given year. Most of the time, the process is entirely uneventful – oil goes in one end of the line and comes out the other at its destination.
Unfortunately, there are very rare moments when the process doesn’t work as it should – a breach of the line occurs and the product is released into the environment. Pipeline-related spills do occur, and often become major news – and examples for opponents of pipeline construction to use for their own devices.
The transmission industry has been looking for better ways of protecting the environment from oil spills. One proactive option being proposed is to use a double wall system, intended to keep the product in the pipeline should any issues occur on the main line.
At present, spill prevention and detection involves a number of technologies ranging from corrosion coatings to remote sensing and operations. Those methods work – to an extent – but often it’s not the technology that detects a problem.
“It’s usually the local farmer or someone who works on the pipeline that happens to be going along and inspecting lines that will notice there’s a spill,” related Jefferson Adler, president and CEO of Podium Energy, an Edmonton-based technology company. “A lot of pipes are underground, so it takes a lot of time for them to determine where the spot is. Even if they know there is a spill, they can’t actually determine where the spill is along the line.”
Small leaks can sneak by
Large leaks get picked up quickly by the transmission company or local residents. Smaller breaches of pipelines may go undetected for a significant length of time. If a small leak occurs in the system but doesn’t get picked up right away, it could run for quite a while before being noticed.
“Small is relative,” Adler said. “If you look at North Dakota, where they had a spill, within a day and a half they lost 625,000 gallons or so. The hole on top was about the size of a little garden hose, and yet it took them so long to determine what the cause was.”
In recent years, the advent of fibreoptic cables has brought new tools to the leak detection area, though those too are limited. Detection methods have a large part to play in reducing spills, but Adler and Podium Energy have proposed a different approach: using double-wall pipe in conjunction with modern detection equipment to contain spills as they occur.
“We have reactive technologies in the industry right now, but none of them offer any kind of containment, which is a big issue for folks who want to make sure that if there is a potential need they can contain it,” he said.
Podium Energy’s EarthSafe pipeline technology puts containment into the mix by incorporating a double-wall pipe, fitted with numerous sensors and other features, into the design of the pipeline.
Bulkheads block oil flow
The line is designed in segments that feature bulkheads within the gap between the inside and outside pipes which contain any liquids that may leak. Sensors within the gap are placed to pick up any indication of an oil leak; if they are triggered, a warning goes out to the control centre and emergency protocols are put in place.
“There are some double-wall pipelines in use right now, but in most cases they’re being used as an insulating factor. For example, there was a spill out West that about a kilometre away from the refinery – it was a brand-new pipe and double-walled,” Adler said. “The issue with that is the pipe was filled with insulation – it was more designed to keep the temperatures of the hydrocarbons at a certain level.”
In the EarthSafe model proposed by Podium, the main line is surrounded by a second pipe installed in a modular manner. Each 50-foot segment has bulkheads on either end, and is equipped with liquid sensors that can detect any infiltration into that air gap within moments of the leak taking place. If the liquid sensors are tripped, operators are notified and, in many cases, valves can be automatically closed to prevent any fluids from spreading out along the pipeline right of way.
If the leak isn’t immediately responded to, or if the outflow is significant, then the outer pipe may fill up between those bulkheads. That essentially closes the leak as the product reaches a similar pressure as the material in the surrounding pipe, and forces product to continue flowing through the system. All the material that was released remains in the pipe.
The modularity and flexibility of EarthSafe is what makes it attractive, Adler said. Construction can be done easily using the company’s preferred materials and technologies.
“If you have a certain acoustic system that you have a preference for that goes through your entire pipeline infrastructure, we will continue to use that and we’ll wire it in within our system,” he said. “If you have a fibreoptic system… the beauty of this system is that it’s almost like LEGO – it’s very modular.”
In addition, the sensor system within the outer wall can provide a snapshot of other potential problems that may later lead to more serious consequences.
“We don’t just detect oil or natural gas or whatever liquefied substance is flooding out,” Adler said. “If there was significant corrosion to the pipes and failure occurred where you had a little bit of precipitation coming into the pipe, that would notify the operator as well.”
With the modular design, the system can be used to protect the environment by placing segments of transmission pipelines in potentially sensitive areas.
“There are a few selective areas that are eco-sensitive – next to water, aquifers, near urban centres or ecosystems where there are some endangered species,” Adler said. “These are specific places where you might want to place EarthSafe, then connect with your existing single-wall lines.”
At present, the EarthSafe system is still conceptual, but interest has been very strong. Adler has spoken at a number of pipeline-related events including making contacts with government and pipeline operators. Response to the idea has been strong.
“There is a cost… but at the end of the day the cost of a cleanup could be significant,” Adler said. “We feel confident that in the next little while some firm might want to pick this up and implement it in eco-sensitive areas. If you do have a spill, from an environmental perspective, it could be very, very expensive. Many spills take years to clean up. Our technology is so modular that they could go in and just remedy one section. Not a drop will touch the ground.” OGPN