Biodiesel: Cruising On The Fat Of The Land

Page 2

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"Toxic Woman" (Mia in this case) goes to Canada. We took turns being Toxic Woman; there were plenty of opportunities to go around.

Along the way people we met tried to understand how we created the processor, and why. "Nobody would believe that we weren't engineering students or chemistry majors," says Mia. "A lot of them were almost angry. They'd say, 'This doesn't make any sense. It's so much easier to buy fuel.'" Melissa adds, "People thought we were brewing moonshine or making bombs or something like that."

There's nothing like hazardous chemicals and a respirator to help one make friends. Carl found us sooooo interesting. He's too crusty to worry about a few chemicals.

We also had to contend with the unpleasant task of acquiring and filtering used vegetable oil from restaurants in the middle of the summer. "At times it was 100 degrees with 90 percent humidity, and we were walking around behind diners opening up these dumpster-like things where oil is kept," says Melissa.
"Most restaurant owners would look at us like we were crazy for wanting the oil," Emily says. "They were, like, 'Sure you can take it if you want, but it's so gross.'"

A 55-gallon drum, a drill with a paint mixing attachment, a hot water heating element and a brass ball valve can create magic with just a few caustic chemicals. The long tube is for venting the drill motor.

We weren't quite sure what biodiesel was supposed to look like, but that didn't really matter because the smell was so overwhelmingly bad.

For better or for worse, here goes the final product into the Bioburban fuel tank. When the motor ran, the exhaust smelled sort of like burning french fries.

One batch went bad (pH = 11) because it contained too much lye, so we had to clean out the processor. Oops, I guess we won't be leaving on time after all.
By the end of the trip, we had a sack filled with clothes that were covered in vegetable oil and grease.

Navigating

And, of course we had to figure out where we wanted to drive each day. For a truck, the Bioburban was efficient with fuel, since diesel engines are more efficient than gas engines. It got about 20 miles per gallon compared to a Suburban running on regular gas which would get around 14 miles per gallon. We had to stop to make fuel five times on our trip.

Epilogue

Biodiesel burns with less pollution than petroleum-based diesel fuel, and it is a renewable resource. On the other hand, it isn't a panacea. It has its own agricultural environmental impacts and in cold weather it tends to gel. But the project was extremely worthwhile.
"When you're a Carleton student and everything you do is so brainy, it's fun to use your hands and be technical and mechanical," says Emily. "The Bioburban trip was a wonderful experience, but it was also incredibly intense."

Editing by Tim Vick
Photos mostly by Anna Moseley
Some text from the Carleton Voice, "Out of the frying pan, into the fuel tank," by Erin Peterson, Spring 2002

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And, of course we had to figure out where we wanted to drive each day. For a truck, the Bioburban was efficient with fuel, since diesel engines are more efficient than gas engines. It got about 20 miles per gallon compared to a Suburban running on regular gas which would get around 14 miles per gallon. We had to stop to make fuel five times on our trip.