A smart retrofit for the CSG industry that steps on the gas
The environmental and actual costs of the continuous-bleed positioners are startling. Consider this: GE estimates that across a coal-seam gas operation with 4,500 high-bleed valves, 2,620,050,300 scf (standard cubic feet) would be lost each year in natural gas, costing a whopping $7.86 million in not being able to sell that bled gas. “There are so many control valves, in a remote location, functioning using natural gas as the instrumentation gas,” explains Ibrahim. A single pneumatic valve typically releases about 500,000 standard cubic feet (scf) in bled instrumentation gas each year, the equivalent of 28 tons of CO2, or the average annual greenhouse-gas pollution from five passenger cars. All that just for controlling one valve system.
“We were in Shanghai in a meeting, brainstorming ideas to get into the positioner market in Australia,” explains Ibrahim. “We didn’t think we had anything that came close to the competitor’s low-bleed relay, and then suddenly someone said, ‘Hey, have something that actually has no bleed at all, that can actually work for this application.’ We discovered that the application of our ZERO-bleed positioner fits perfectly into Australia and the CSG industry.”
The GE ZERO bleed Positioner started its career in the natural gas industry in 2009, where it has helped to save time, money and stress in urban applications, where frequent service callouts for “gas leaks” were in fact just residents smelling instrumentation gas being released by pneumatic valves, as part of their normal operations.
This positioner is a game-changer because it’s packing computer power. “The positioner has a motherboard in it just like a computer,” explains Shaun Saunders, senior sales leader for Flow & ProcessTechnologies, GE Oil & Gas. “It really is the brains: without it the valve is just a dumb piece of equipment. It gets sent data from another computer, being the digital control system [DCS] which tells it, ‘I need you now to move the valve to a particular position.’ And then it sends information back to that DCS control system, saying, ‘OK, I’ve moved the valve, and it’s now sitting in that position that you wanted.’ Or if it can’t get there, and then it starts communicating backwards and forwards to try and get it to the position it wants. So that’s the smarts behind it. And then there are a whole lot of smaller mechanical devices that work in conjunction with the electronics to get the valve to move exactly where we want it to be.”
Before the lightbulb moment, GE could install its own valve and actuator mechanics, using positioners manufactured by the company’s competitors. At best, these positioners offered low-bleed emissions, but in many cases they were high-bleed. None of them offered zero bleed. Now, existing gas operations can retrofit the positioner and immediately move to a zero-bleed state—benefiting the bottom line and the ozone layer.
The positioner has a motherboard in it just like a computer, it really is the brains.
“It really is the perfect solution,” says Shaun Saunders of the opportunity for Australian CSG operations. “There are no additional modifications required or upgrades or anything like that. The technology’s already there. We’ve got a number of places where the exact same technology’s been used in Canada, the US and the UK.”
In the US, companies are being encouraged to retrofit traditional, methane-emitting pneumatic valve systems as part of the Environmental Protection Authority’s Natural Gas STAR program, with partners recognised by the EPA as committing to improve their environmental performance. In Australia, companies retrofitting GE’s ZERO-bleed positioners could acquire similar environmentally responsible standing via registering their project with the Clean Energy Regulator under the government’s Emissions Reduction Fund.
On top of the ZERO bleed application’s benefits to the environment and the bottom line, the positioner is also another citizen of GE’s Industrial Internet world. The positioner constantly reports back to its masters, setting it up for a prevent/maintain life, rather than the old break/fix cycle. “It does all sorts of diagnostic capabilities, which can tell us all sorts of things like how many times the valve’s moved in the last hour, in the last day, in the last six months or even two years, if we want,” says Saunders. “So we can do preventative maintenance instead of reactive maintenance by using the software incorporated with the positioner.”
The ZERO bleed positioner can be retrofitted to other valve systems, too, not just GE’s. “There are other companies out there manufacturing valves for applications that we’re not even considering yet,” says Saunders. “This positioner technology could be added to their product in other industries and applications, so the ZERO bleed will quite likely have an even bigger audience than we imagine.”
To help calculate what they could save the planet and the P&L, companies can plug their own valve instrumentation-gas emissions by here.