The final day of the 2014 International Biomass Conference in Orlando featured a tour to Viesel Fuel in Stuart, Florida where we were allowed an up-close view of their state-of-the-art 7.5 million gallon per year biodiesel facility. Viesel staff was happy to present, and all who attended were thrilled to have the opportunity to have a first-hand view of how Viesel aims to revolutionize the biodiesel industry through innovation and strong partnerships.
Viesel is pushing the innovation envelope by utilizing enzymes to convert raw oils into biodiesel. The majority of operating biodiesel plants across the industry use an acid or base solution of alcohol to catalyze and carry the transesterification process of raw veggie and animal oils into glycerin and biodiesel. Viesel, in conjunction with Novozymes, has developed and deployed an enzymatic process that breaks the limits currently constraining the traditional biodiesel industry. “Producing biodiesel with enzymes allows us to use less energy, less chemicals, and lower quality feedstock,” Graham Dowerton, Project Manager at Viesel stated at the beginning of the tour. Higher temperatures and greater amounts of methanol are required in the more traditional processes, which negatively affects the energy required and profitability of traditional plants. By employing an enzyme to act as the catalyst, Viesel only needs to reach a process temperature around 100° F. This saves Viesel considerable energy and thus money throughout the production process. Additionally, compared to more traditional production methods, the enzymatic process requires considerably less methanol. Yet, what excites Viesel most about the enzymatic process is its ability to handle lower quality feedstocks.
Along with higher heat and greater amounts of ethanol needed during processing, traditional biodiesel production facilities are limited by the amount of free fatty acids (FFAs) that can be present in the oil feedstocks. There is a large market of oils and greases that have high concentrations of FFAs and prove to be unavailable to the more traditional facilities. These plants are limited to feedstocks with FFA concentrations of around 5%, according to Viesel staff. Alternatively, the enzymatic process not only tolerates higher concentrations of FFAs but is able to convert them into high quality biodiesel. “FFAs are not a limiting factor in what we can make biodiesel from. They’re actually a viable feedstock,” Becky Hobden, Chemical Engineer at Viesel, explained to tour attendees. Viesel’s ability to process previously unusable feedstocks is not only a boon for Viesel but, according to Hobden, a major breakthrough for the entire biodiesel industry.
The acquisition of feedstock is the costliest part of running a biodiesel facility, with 70% of operating cost at Viesel spent simply on collecting and purchasing various oil feedstocks. Viesel independently collect used cooking oil from roughly one thousand restaurants to cut the cost of feedstock, but this only makes up 5% of the oil that passes through their plant. The rest is purchased from renderers. Minimizing the cost of feedstock dramatically affects their bottom line. According to Dowerton, for every $0.01 saved per pound on feedstock generates $500,000 in savings on an annual basis. While used cooking oil, which has a relatively low concentration of FFAs, costs around $2 per gallon, higher FFA oil, like brown grease, costs around a dollar less. Accessing the brown grease market and converting it into biodiesel is seen as “the Holy Grail of our business,” exclaimed Hobden. Though Viesel’s enzymatic process allows access to lower cost, higher FFA feedstocks, sulfur is the final road block in Viesel’s quest for the ‘Holy Grail’ of biodiesel production.
The EPA limits the amount of sulfur that can be present in on-road and more recently off-road diesel. Biodiesel produced from brown grease can have up to 250 ppm, and with a limit of 15 ppm set by the EPA, brown grease biodiesel is not currently allowed as an approved feedstock. Viesel is working with a number of technology providers to reduce the concentrations of sulfur in brown grease biodiesel, and they say they are close. Once they are able to economically remove the sulfur, they will have found and possess the ‘Holy Grail’ of the biodiesel industry.
Because of Viesel’s unabashed honesty regarding their successes and barriers, the tour was well received by attendees. We saw how they are openly working with a number of partners to streamline the enzymatic biodiesel production process and gain access to underutilized feedstocks. Through innovation and strong partnerships, Viesel is revolutionizing the biodiesel industry.
I would like to thank everybody at Viesel for the highly pertinent and very informative tour. Thank you.
By Kolby Hoagland | Biomass Magazine – March 28, 2014