Corn Ethanol Makers Weigh Switch to Butanol
by Henry Fountain (New York Times) Nearly a decade after the adoption of federal renewable fuel standards led to a sharp increase in production of ethanol, some producers in the Corn Belt are considering making a different fuel. The fuel, butyl alcohol, or butanol, is worth more to refiners because it has more energy than ethanol, is easier to handle and more of it can be blended into each gallon of gasoline. But producing it will require costly retrofitting of ethanol plants, and plant capacity will be reduced.
Several companies are leading the push for butanol, including Gevo of Englewood, Colo., and Butamax Advanced Biofuels, a joint venture of BP and DuPont based in Wilmington, Del. They have developed ways to make butanol the same way ethanol is made, through yeast-based fermentation and then distillation.
…Butamax is producing butanol at a demonstration plant in Hull, England. And in the United States, it has organized an alliance of ethanol producers who are considering making the shift. The idea, Mr. Beckwith said, is to convert many plants simultaneously, beginning in 2013.
…Butamax estimates that converting an ethanol plant will cost 20 percent to 30 percent of a plant’s original price tag — perhaps $10 million to $15 million for one the size of Highwater’s, more for larger facilities. The conversion will also reduce a plant’s capacity about 20 percent, the company said, but the greater value of butanol should more than make up for the lost volume.
…Butanol offers several advantages to gasoline refiners, Mr. Beckwith said. It contains about 30 percent more energy than ethanol, and it can be blended with gasoline at a higher percentage — Butamax recommends 16 percent butanol, compared with the current 10 percent standard for ethanol. That would allow refiners to more quickly meet the Environmental Protection Agency’s renewable fuel standards, which were adopted in 2005 and mandate that transportation fuels contain increasing amounts of alternative fuels over time.
Because ethanol evaporates relatively easily, refiners have to remove some of the lighter components from their gasoline so the blended product meets air-quality standards. Butanol evaporates less readily, so refiners can leave many of these more volatile components in, saving money. READ MORE