The ethanol industry has been anticipating this for a couple of years, but it still snuck up on some of us – the EPA (Environmental Protection Agency) Tier III compliance is required as of January 1, 2017. Fuel ethanol producers need to be aware that they must be able to demonstrate that their product consistently meets the new 10 parts-per-million (ppm) organic sulfur standard. Similar to other pending regulations on the fuel ethanol producer, the EPA Tier III compliance documentation process has not yet been published. The previous EPA Tier II standard that defined the sulfur limit at 30 ppm has been in effect since 2000.
While achieving the maximum sulfur limit of 10 ppm has historically not been difficult, documentation may be. As Kelly Davis of the Renewable Fuels Association recently stated during an interview for the July 15, 2016 edition of Ethanol Producer Magazine, direct demonstration of compliance can be costly. “They can buy a [organic] sulfur analyzer and take on the regulatory responsibility, certifying all their batch loads and making sure their sulfur analyses are valid. There's also details like product transfer documents and annual EPA reporting.” The analytical equipment is priced in the $70,000 range and requires training to use and maintain, and consumables.
If a producer chooses not to go down the analytical road, they must obtain a verified certificate of analysis (COA) from an EPA-certified denaturant supplier and report a calculated sulfur value for denatured fuel ethanol leaving their facility. It's suggested that plants contact their denaturant supplier to verify status.
Ethanol itself is clean and organic sulfur is not present. However, inorganic sulfur is present in 200 proof ethanol at low ppm levels as “existent sulfate” (in reality sulfuric acid H2SO4) and “potential sulfate” (in reality the combination of H2SO4 and sulfurous acid H2SO3). High inorganic sulfate levels in ethanol have been alleged to cause damage to engine fuel injectors and distribution filters. The relevant American Society of Testing & Materials (ASTM) standards have their own expensive equipment and procedural requirements.
As of earlier this year, the standards specified a maximum level of 4 ppm existent sulfate. This maximum applied to E10 use in non-flex-fuel vehicles. Now, as mid-level blends have become more popular (and vital to fuel ethanol industry growth), certain ASTM members including motor fuel marketers and automobile manufacturers have proposed tightened limits on the inorganic sulfate in ethanol. Tier III will include permissible “sulfate” levels in E15.
In the interest of our customers and the industry, U.S. Water has been working since 2007 to reduce the use of sulfur compounds in the ethanol productions process. The solutions offered by U.S. Water have demonstrated returns to the ethanol plants in the form of reduced sulfate issues, minimized downtime and higher plant efficiency. Contact your U.S. Water Representative for more information.