US oilseed plants working to meet new EPA rules on hexane

Related tags United states environmental protection agency

Oilseed crushing plants across the United States are working to
implement new rules issued by the Environmental Protection Agency
to lower their emissions of hexane.

Oilseed crushing plants across the United States are working to implement new rules issued by the Environmental Protection Agency to lower their emissions of hexane.

Hexane is a volatile solvent that is used to separate oil from the meal. Most of the hexane used by the plants is captured and reused, but a small amount escapes into the environment. The EPA adopted a regulation in April 2001 that would reduce the total amount of hexane released by oilseed crushing plants by about 25 per cent over three years.

"This is the first standard we have ever seen,"​ says Neil Turnbull, general manager of the Montola Growers oilseed plant in Montana. "It's the first time they have put a limit on hexane."

Hexane is not a carcinogen, but can cause dizziness and irritation and, with long-term exposure, nerve damage. It is regulated as a volatile organic compound, a class of compounds that contributes to smog problems. The goal of the regulation is to reduce hexane emissions by 6,800 tons per year and total VOC emissions by 10,600 tons from the 109 existing oilseed plants covered by the rule. Plants that crush corn, cottonseed, peanuts, rapeseed including canola, safflower, soybeans and sunflowers are covered by the regulation.

The regulation allows the emission of between 0.2 gallons and 1.2 gallons of hexane per ton of oilseeds processed, depending on what kind of seeds the plant crushes and whether it is a new or existing source. The EPA set the standards based on the operating plants with the lowest levels of emissions. The rule treats each plant as a single source, allowing companies to figure out the best way to cut their emissions rather than mandating that specific pollution control equipment be installed.

The EPA estimates the rule will cost the oilseed industry $12 million (€12.7m) per year to implement.The impact of the new rule won't be negative, says Turnbull. Montola Growers produces safflower and canola oil, along with some specialty oils. The machinery Montola is installing will reduce its hexane emissions by about 15 per cent.

"It's going to be an important project,"​ Turnbull says. "I guess it will be a major project. We're hoping that it will allow us to become even more efficient in extraction. With new goals to meet, maybe it will allow us to put in some new equipment that will enable us to do a better job of what we are doing."

The Cenex-Harvest States soybean crushing plant in Minnesota, already is in compliance with the new rule, says production manager Jerry Hawker. The cooperative is building a second oilseed plant that will open in 2003 and will be designed with the new standards in mind.

"A vice president of manufacturing, Jerry Corbits, helped set this standard,"​ Hawker says. "That's the reason why we are where we're at. He said we have to be there before this ever happened."

While the changes to the plant will be significant, Turnbull doesn't see them having a major impact on Montola's operations. Modifying and upgrading the equipment will be an eight- or nine- month project, he says.

"We've done some of the work, but not all of it yet,"​ Turnbull says. "The work has to do with the extraction efficiencies and to make sure there are no leaks for the hexane to get out. We do that on a continuing maintenance basis anyway."

Related topics Processing & Packaging

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