CLEAR THE AIR

Breaking down the myths of emission control

by Shanna Germain

    ASK FIVE PEOPLE in the coffee industry the same question about air quality control, and you’re likely to get five different answers. That’s because emission control is confusing, often misunderstood, and riddled with myths and misconceptions.
    Here, we tackle the top 10 myths about air quality control in an attempt to clear the air and sort the facts from the fiction.
    But first off, let’s look at what all the fuss is about: Why should coffee roasters care about emissions?
    When coffee beans are roasted, they release a number of emissions, including volatile organic compounds, particulate matter and combustion products. While some of these emissions come from compounds within the green coffee beans that decompose or oxidize during roasting, others come from the process of roasting itself. Because roasters are typically gas-fired, carbon monoxide and carbon dioxide emissions occur as a result of fuel combustion. The roaster is also the main source of gaseous pollutants, including alcohols, aldehydes, organic acids, and nitrogen and sulfur compounds. When all of these emissions mix together, it forms smoke.
    “Smoke is actually particulate matter suspended,” says Shawn Hamilton, vice president of operations and green coffee buyer for Java City. “It’s little tiny chunks of stuff like coffee oils, tars, and bean fibers. And that’s what everyone worries about, because if you breathe those, they get into your lungs and they stick there.”
    That’s where oxidizers, commonly called afterburners and catalytic incinerators, come into play. An afterburner is a gas burner chamber that uses high heat to break down the odor and smoke and convert it into water vapor and carbon dioxide.
“Basically, it burns those particulates into nothing, or at least makes them so small that they’re beyond the scope of what the air quality management district looks for,” says Hamilton.
    Seems simple enough, right? But the truth is that there is much more to clear air than meets the eye (or the nose).

Myth #1: The EPA regulates roasting emissions

This seems to be the number one misconception about emission control. While the Environmental Protection Agency (EPA) does have a hand in regulating emissions of all types, the truth is a little less concrete. First off, it’s hard to find anyone at the EPA who knows exactly what the regulations are for coffee roasters.
    Many people believe that’s because the EPA has bigger fish to fry at the moment. “The EPA’s worried about coal-fired power plants, refineries, and pulp mills,” says Steve Van Slyke, supervisory engineer for the permit engineering team for the Puget Sound Clean Air Agency. “At this point, coffee roasters just don’t get up very high on their radar screen.”
    Instead, it’s the state or local jurisdiction that really regulates coffee roasters, says John Keenan, environmental engineer with the EPA. If you’re planning to build a new roastery, or even upgrade an old one, you’ll need to go through the state and local construction permit processes in your area. “This is a good opportunity to ask what is required of you when it comes to air emission control,” Keenan says.
    Which brings us to…

Myth #2: Emission standards are the same everywhere

Not true at all, says Keenan. “The standards are all over the map. If you’re in rural Montana, you’re going to get a different standard than if you’re in downtown San Diego.”
    Van Slyke agrees, saying that forewarned is forearmed. “Always check with the agency that has responsibility for air permits in your area,” he urges. He says he’s seen too many instances where people start a coffee roastery without checking the regulations, and realizes six weeks into their business that they need an afterburner. “And then it’s an unexpected expense that hasn’t been build into their business plan,” he says.
    And it’s not just regulations that differ from area to area, the costs vary nearly as much as the requirements. In some areas, the process costs a chunk of change and time: $2,000 plus two pages worth of forms to fill out. In other areas, the cost is as low as $150 and a verbal notification that you’re going to install an afterburner.

Myth #3: Every roastery must have emission control

Legally, this isn’t true. Some state and local agencies don’t set any emission requirements at all. “The million-dollar question is: Do I need an afterburner or don’t I?” says Michael Whitley, director of sales and marketing for Diedrich Manufacturing. “The regulations differ from Topeka to Taiwan, from Seattle to Singapore.”
    The answer, again, can be found with the local governing jurisdictions. “What we recommend is that you contact your local air quality management district and say: ‘I’m working on a business plan that includes coffee roasting. Do I have any regulations I need to consider?’” Whitley says.
    Terry Davis, president of Ambex, Inc. suggests that roasters do their afterburner homework before they dive in head-first. “Most people jump to the conclusion that they have to have an afterburner,” says Davis. “But don’t assume you need an afterburner. Don’t take anybody’s word for it. Do the research yourself.”
    However, there’s another side to this argument: Even if emission control is not a legal requirement, many roasters argue that it is a social and environmental requirement. “There is damage we are doing when we don’t have some kind of smoke control,” says Donald Schoenholt, president and coffeeman at Gillies Coffee Company. “Smoke is filled with an awful lot of stuff that you really don’t want to put in the atmosphere unless you have a death wish for the air and, oh yeah, for your great grandchildren.”
    While Schoenholt admits that it’s easy to understand why roasters don’t want smoke abatement equipment, he believes it’s the neighborly thing to do.
    “They don’t want it, and I don’t blame them, because it’s lot of money,” he says. “But they have to understand that if you’re going to be a smoker, it’s polite to use an ashtray. You don’t just put the ashes on your mother-in-law’s couch. It’s a question of good manners, and of being a good neighbor.”
    Schoenholt equates today’s afterburner situation with that of chaff collectors in the past. “Today, no roaster would think of putting in a roaster without a chaff collector, but there was a time when there was no such thing as a chaff collector and all the ash and all the dust and all the chaff—some of it still burning—would just go out into the street and into the neighborhood,” he says. “Nobody even thinks of operating without a chaff collector today. Yet, we still haven’t learned our lesson with smoke control.”

Myth #4: It’s all about pollution

“This is kind of a misnomer,” admits Davis. “The biggest issue with coffee roasters falls more on the nuisance side than on the pollution side.”
    That’s because regulatory agencies are often so busy that they don’t check into something unless there’s a complaint. And typically the complaints are visible smoke or odor-related.
    “The real issue is odors from the coffee roasters, big or small,” Van Slyke says. “In some ways, it’s the smaller [roasters] that have more challenges because they tend to be in neighborhoods, where people notice it more.”

Myth #5: An afterburner is the only choice

While the term afterburner is the one you hear most often when it comes to emission control, there are actually a few options for roasters.
    For those who are having nuisance problems, one option is dispersion. “Dispersion is where you put a blower outside the stack that mixes fresh air with the nuisance smoke so that you can pass the opacity test,” Davis says. Although the method may sound a little sketchy, Davis says it’s legal as long as the roastery is having a nuisance problem and not a pollution problem.
    When it comes to pollution-control devices, two basic types are readily available in the United States:
    Afterburners are the most common. These machines use a power burner to oxidize the smoke and smell when they run between 1,200 and 1,400 degrees.
The problem? “Afterburners are huge energy hogs,” says Davis. “All of a sudden, your gas bill is humongous.” Not only that, but they require costly triple-wall ducting due to the high temperatures, and they take up a lot of space.
    Catalytic incinerators are a second option. While catalytic incinerators have to get to the same high temperature as regular afterburners, once they hit that temperature, catalysts inside the machine light off and feed off the smoke. But catalysts can be tricky because they get dirty and have to be cleaned and/or replaced.
    There is also a third option, which, while still new, is slowly growing. These are a new breed of roasters that take care of roasting and afterburning all in one machine. Lilla offers machines with afterburners already attached, while Loring Smart Roaster has designed a machine that reuses the already-heated air from the roasting process to burn away emissions, thus decreasing energy use and costs.

Myth #6: You match the after-burner to the size of the roaster

This seems to be half-myth and half-truth. While some afterburners are matched to the size of the roaster (for example, Diedrich makes an afterburner that specifically fits each of their roasters), if you’re trying to match machines from different manufacturers together, the measurements can be tricky.
    “You can’t necessarily just mix and match any roaster with any afterburner,” says Whitley. “You want to consider the size and the airflow.” Airflow is important because in order for the roaster to perform properly, the air flow cannot be restricted by the afterburner. Best bet? Find an expert to help you match your machines.

Myth #7: You have to do it all yourself

Typically, all you have to do is ask, and someone will help you with the process. Many companies that make and sell afterburners not only help you set up the machine and get it running, they will also complete the paperwork and assist you with the inspection process.
    “When someone buys an afterburner, we do all the environmental work for them,” says Marty G. Curtis, founder and owner of Combustion Systems Sales & Service Inc. Not only does Curtis file the paperwork, he waits at the roastery while the proper officials check it out. That way he can make any necessary changes to get everything working up to spec.     “What we tell people is when you buy your air pollution equipment, make sure whoever you buy it from is willing to come out and have it installed and help get it signed off when the environmental people are there.”

Myth #8: Emission control will solve everything

Not so, especially when the issue is one of nuisance and not of compliance, says Lincoln Fowler, co-owner of Alterra Coffee Roasting, which recently won a Green Power Leadership Award from the EPA. “Many people think they’ll put an afterburner on and solve the situation entirely,” he says. “But depending on what temperature you run you may burn all the smoke and the particulate will disappear, but you can still have an odor.”
    Fowler has found that a temperature of 1,100–1,200 will incinerate smoke but leave odor, while an afterburner running at 1,300 degrees will eliminate both smoke and odor.
    And then there’s another issue that doesn’t seem to have anything to do with air quality control, but which can cause a headache or two just the same, as Schoenholt recently found out. Last year, Gillies was cited by the New York City Department of Environmental Protection for polluting the air around his plant with “offensive coffee odors.”
    But it wasn’t odor from the roasting process that had the city up in arms. Instead, it was the fragrance of the already roasted coffee degassing. “We weren’t roasting, but the building is filled with little valve bags that release the smell of fresh-roasted beans,” Schoenholt says. “So if you happen to be near that stuff, there’s a reasonable chance—like 100 percent—that the ambient air is going to smell like coffee. And, in New York City, that’s apparently against the law.”
    The city fined Gillies $400, but Schoenholt argued that the city didn’t have a case, because coffee was a naturally occurring fragrance (like flowers), and he spent nearly $30,000 in legal fees to try to prove it. At this point, the case is still in appeal.
    But Schoenholt worries that there’s a bigger issue at stake. “My concern is that this is a test case for the world,” he says. “Suppose San Francisco says, ‘Hey, New York got away with it, so you can’t have any smells here either.’ If this interpretation is let stand, there could be tremendous pressure on the specialty coffee community to keep these naturally occurring smells from leaking out of the building.”

Myth #9: Emission control is a one-time deal

Of course, the issue of emission compliance doesn’t end once you’ve installed the necessary equipment and crossed all the T’s. In most places, regular inspections are also part of the deal.
    “In Sacramento, we’re allowed three minutes per hour of smoke over 20 percent capacity. So every year, someone comes and sits across the street with a stop watch for an hour and they read the smoke,” says Hamilton.
    Inspectors also look at the company’s emission records—logs that record the number of pounds per roast, roasts per day, and what the operating temperature of the afterburner was at the end of the roast. At first, Hamilton admits, the “smoke readers” were fairly uncooperative and would give the company violations without explaining how to fix them. When Hamilton realized that the fines were estimated to be $10,000, he decided there had to be a better way. “I wanted to learn what was and wasn’t a violation so I could make it better,” he says. “So I went to pollution school.”
    In school, Hamilton learned how to read smoke by sight and to know what percent of the smoke was particulate. Now, he says, he talks “smoke smack” with the inspectors and tries to make sure he’s doing everything to stay on their good side. “The trick with those guys is, don’t argue with them,” he says. “Try to work with them, and try to understand what they do.”
    If worse comes to worse and you find yourself in the middle of a situation with an agency, don’t panic. Although the chances are good that you’ll get a fine, they probably won’t force you to shut your doors.
    “If you do receive a complaint, they won’t just come in the door and shut you down,” says Davis. “That never, ever happens, so don’t panic. You’ll probably have to take action—buy an afterburner or whatever, but they’re not going to shut you down.”

Myth #10: Emissions control is too hard

    Okay, so this isn’t really a myth, but after reading this article, you might think it is. But roasters who have gone through the process say it isn’t as difficult as it appears. Figure out what’s expected ahead of time, build the expense of emissions control into your budget, ask others for help, and you should be operating in the blue in no time.