But the distillation is more energy efficient depending on the order in which the columns are operated.
"There are many ways to arrange the columns," Agrawal said.
Shah created a computer algorithm that identifies all of the possible sequences and then determines which require the least heat and energy. The Purdue researchers used their new technique to determine there are nearly 6,000 possible sequences for the four columns used in petroleum distillation.
"Once we know all of the possible ways they can be arranged, then we can tell you which ones have the potential to be the most energy efficient," Agrawal said.
Petroleum refineries have been using the same sequence for about 75 years, and it is the most energy efficient of the sequences known to industry, the Purdue researchers confirmed using their new method.
The researchers also determined, however, that 70 of the new sequences identified have potential to consume less energy than the sequence now used by industry. Those 70 sequences range from being 6 percent to 48 percent more energy efficient than the method currently in use.
"However, just because a particular sequence would be more energy efficient doesn't mean it would be practical for industry to implement," Agrawal said. "There are a lot of challenges. Some are easy to build and just involve trivial retrofitting, and some are more difficult. So we'll need to work with companies and refinery experts to determine which sequences could be built."
|Contact: Emil Venere|