Alberta’s natural gas- processing companies could save millions of dollars in energy costs and make cuts in greenhouse gas emissions if operating rules for sour gas plants were changed, industry experts say.
Alberta Environment says it likes the idea, and will consider changing regulations for the more than 50 sour gas plants in the province, providing the facilities continue to meet stringent emission and air-quality standards.
“We would support any pilot project or test cases” on a proposal now being readied by environmental consultants and gas plant operators, says Alberta Environment spokesman Robert Moyles.
“Certainly, it fit well with our climate-change plan,” Moyles says. “It’s just a question of making sure those (environmental) standards are maintained and the guidelines are met.”
John Sames, president of Sulphur Experts Inc. in Calgary and an internationally recognized authority on sour gas plant operations, says he’s confident Alberta’s gas plants can run more efficiently and use less energy while still maintaining air quality standards.
“This is a brand-new opportunity because of Kyoto, basically,” Sames says, referring to the international accord to reduce greenhouse gas emissions such as carbon dioxide or CO2. “There’s an opportunity here for CO2 reductions that we really didn’t address before.”
Provincial regulations that are now 30 years old treat all sour gas plants as if they were running full out, processing the maximum amount of gas they were designed for, Sames explains.
This means an operator must burn enough “fuel gas” – the natural gas used to run the plant – to keep temperatures to a certain minimum level in the top of the facility’s incinerator stack. This ensures the plant can meet its licensed emissions limit for sulphur and other air quality guidelines.
But because of declining natural gas reserves, most of Alberta’s sour gas plants are no longer running at full capacity. Sames and other industry experts say that provincial regulations no longer reflect the actual operating conditions at most plants.
Regulations don’t allow plant operators to adjust the incinerator stack temperatures to match the reduced amount of gas that’s being processed on a daily basis, says Shelley Hittel of Central Alberta Midstream, a gas-processing company.
Instead, “the stack-top temperature is generally based on what the design capacity or licensed capacity of your facility is,” she says.
A plant might be licensed to emit 15 tonnes a day of sulphur dioxide, for example, yet might actually be emitting only 10 tonnes or less because it’s not operating at full capacity.
“If we could lower our stack-top temperature and actually cut back (on fuel gas) by one-third, there’s significant savings there,” Hittel says. It should be technologically feasible to lower stack-top temperatures and still meet provincial air quality regulations, she adds.
Sames notes that an earlier program he worked on in the 1980s proved it was possible for gas plants – then running at full capacity – to lower stack-top temperatures, use less fuel gas and still meet all regulations.
The idea needs to be taken further, now that most plants are no longer running at full loads yet still need to reduce greenhouse gases, he says. “We’re trying to reduce the amount of tonnes of CO2 going up the stack, and at the same time get the fuel economy . . . .”
He expects that most plants will be able to save one-third to one-half in fuel gas costs – which translates into millions of dollars across the industry.
At the same time, there would be a correspondingly large drop in greenhouse gases, amounting to “hundreds of thousands of tonnes” for all of Alberta’s sour gas plants, he says.
With the money saved on fuel gas costs, plant operators could also upgrade their incineration unit, further improving energy efficiency, Sames adds.
“These things could pay themselves out in six months quite easily for a big plant.”
Sames is putting together a proposal for CETAC-WEST, a Calgary-based group working on improving the upstream oil and gas industry’s energy efficiency. The plan is to do a pilot project on one or more gas plants to prove the concept works.
David Pryce, vice-president of Western Canada operations for the Canadian Association of Petroleum Producers, says: “I’m sure the concept would be attractive to the industry if they can look for ways to save costs and still maintain policy objectives around emissions management.”
The Petroleum Technology Alliance Canada (PTAC) has partnered with CETAC-WEST to raise funds from industry for the pilot project and to invite Alberta Environment and other regulators to participate.
“Then the regulators will have the information they need in order to come up with something that works for everyone,” says PTAC president Eric Lloyd.
Moyles of Alberta Environment says the idea “makes a lot of sense” and the department would consider contributing funding for a pilot project.
“It’s definitely something that we can move forward on.”
