By Holly Fesperman LeeSalisbury Post
If you like the smell of french fries, biodiesel fuel might be for you.
Kelly Snider makes the alternative fuel out of used cooking oil for the Piedmont Research Station and he says the exhaust from farm trucks that run off the fuel might make you hungry ó it really does smell like the deep fried potatoes many people crave.
Andy Corriher, who works at the research station, and Snider, operations manager, started investigating how to make biodiesel in 2006 after the research station received a grant from the Tobacco Foundation.
The foundation wants to look into other crops that can replace tobacco as cigarette sales drop, Snider said.
Snider is trying to determine if North Carolina farmers can profit from growing oil seed crops like soybean and canola to make biodiesel fuel.
When he first started, Snider turned to local restaurants to get used cooking oil. Now, he gets it in larger quantities from Piedmont Correctional Institute in Salisbury and the Mountain State Fair near Asheville.
Snider picks up large plastic totes full of the used oil about once every month or two and brings it back to what research station employees call “the old shop,” where the biodiesel operation is set up.
“When the cooking oil comes back here it has french fries and all kinds of crap in it,” Snider said.
Since most of the leftover food and crumbs fall to the bottom, Snider pumps off the clean oil on top and pours it in the heating tank.
Snider pours 80 gallons of used oil in the biodiesel setup at a time and the heating tank is the first step. It heats the oil to 110 degrees.
“The oil flows better when it’s heated up and the reaction goes quicker,” he said.
Next, the oil goes to a tank where it’s mixed with specific amounts of methanol (racing gas) and potassium hydroxide.
Snider performs a calculation called a titration that helps him determine how much catalyst (methanol and potassium hydroxide) he needs to turn the cooking oil into biodiesel.
Getting the right amount is key.
If Snider doesn’t put in enough there’s no reaction.
“If you get too much you’ll have mush. That’s what it looks like because I’ve done it,” Snider said.
After the reaction is complete, Snider is left with biodiesel and glycerin.
The liquid is pumped into a wash tank where the glycerin settles to the bottom. Water flows through the biodiesel to help clean out any trash.
Snider said he washes the mixture about three times.
He pumps the glycerin out and puts it in large plastic containers.
Right now Snider is trying to determine if the farm can use the glycerin or sell it to another company.
Since glycerin is basically sugar, he’s sent samples to the state to see if the farm can get permission to feed it to cows as an energy source.
Glycerin is also found in almost all lotions, soaps and cosmetics.
The biodiesel also goes through a bubble wash in addition to the first wash cycle.
Snider explained that he’s got an aquarium bubbler on top of the tank and it bubbles the water up through the mixture to help cleanse it more.
For the final step, the biodiesel goes to a drying tank that works to evaporate out any water in the mixture.
That last step is vital, according to Snider.
Some people say you can take the biodiesel right out of the wash tank and put it in your truck.
“I don’t recommend that at all, I think that’s a bad idea,” he said.
From 80 gallons of cooking oil, Snider can make about 75 gallons of biodiesel.
The whole process takes about three hours and that’s generous.
While Snider said the fuel economy isn’t really any better or worse than regular diesel fuel, the cost is what make biodiesel so attractive as an alternative fuel.
Snider can make the fuel for 75 cents a gallon as opposed to more than $3 per gallon that consumers pay at the diesel pumps.
That 75 cents covers the cost of buying the methanol and potassium hydroxide. Snider gets the cooking oil for free.
Snider can make biodiesel from new cooking oil, but that makes it more expensive.
The equipment cost about $4,500 and Snider said it hasn’t paid for itself yet but it will.
The farm pumps the biodiesel into a large tank that has a pump and meter on it to fill tucks and other farm equipment.
Snider said the trucks need to be diesel engines to start with, but other than that, no modifications are needed to run biodiesel.
During the summer, the farm can use 100 percent biodiesel in the trucks, but in the winter it has to be a mixture.
Vegetable oil will still retain its liquid form to about 35 degrees, but much colder than that and it starts to gel up, Snider said.
With a mixture, the fuel will stay liquid down to 10 degrees.
Snider is also looking at using rendered chicken fat to make biodiesel.
In addition to using biodiesel in some of the farm trucks, Snider burns it in a furnace to heat the old shop so he can keep his operation going during the winter.
But Wayne Wilson, the farm maintenance man, had to make a slight modification to the air intake value.
Snider said a person could, in theory, use biodiesel to run their diesel furnace at home but the house might smell like fries.
In addition to the cheaper cost, Snider pointed out that biodiesel is friendly to the environment.
A diesel fuel spill requires a special cleanup, but biodiesel is biodegradable.
As far as whether or not North Carolina farmers can grow oil seed crops for biodiesel and make a profit, Snider said he’s still working on it.
“Right now a bushel of soybeans makes about a gallon and a half of biodiesel. That same bushel is worth $10,” he said.
“From that aspect, it’s not economically feasible to do it,” Snider said.
But canola produces a little more than twice what soybeans produce, so Snider is testing to see if that crop might serve farmers better.
Both soybeans and canola have a mill that can be sold after the oil is pressed from the seeds. Snider said soybean mill goes for $250 a ton.
The two crops also grow in different seasons.
“We hope we’ll be able to grow them both in the same field in the same year,” Snider said.
“Part of a research stations job is to look for alternative crops for farms and alternative markets for cops. We’re trying to help the agriculture industry of the state is what it amounts to,” Snider said.
Contact Holly Lee at 704-797-7683 or hlee@salisburypost.com.