UWRF ag science engineering department acquires seed press

The UW-River Falls agricultural science engineering department has acquired a new machine for its bio-diesel research. The $7,500 machine, called a seed press, was purchased in December from a manufacturer in Eau Claire.

Students are still testing the press to maximize its efficiency, but when ready it could produce additional oil to power the campus farm equipment and process animal feed to supplement the farm’s several dozen cattle.

The machine is currently in the engineering annex of the Ag Science building. Students use soybeans with it because they are common to the region around UWRF, relatively clean and a good balance between the amount of oil and feed produced, ag engineering chair Dean Olson said.

Senior ag engineering majors William Pettis and Eli Chandler are among the students experimenting with the machine.

“[It’s] not that loud, actually,” Chandler said. “It runs about twice as loud as an Xbox 360.”

With the help of senior Dan Volkert and junior Sam Vorpahl (also ag engineering majors), Chandler and Pettis demonstrated the press for the Student Voice. Under Olson’s supervision, a quarter bushel of soybeans was poured into the machine, producing 400 milliliters of oil and enough pellets to feed a cow for a day.

Olson said this could probably be improved over time.

“They’re still figuring it out, but we can expect about a gallon of oil per bushel of soybeans,” Olson said. “I see our lab farm going through 1,500 bushels of soybeans per year, [and] roughly 1,500 gallons of oil per year… would be about 20, 25 percent of the oil needed for the lab equipment.”

The press is a few feet long and powered by an electric motor. First, the beans are stored in a large bin mounted above the machine. When released, the beans pour down through a funnel into the front of the press. The machine takes a few minutes to prime, and then the seeds are ground up by a large internal screw and crushed against a press plate. The oil drips out through a perforated column into a cup, while the remaining soy pellets are squeezed out of a nozzle on the end.

The oil can be run through a bio-diesel processor and used in equipment. The feed is gathered in bins, heated and given to the cattle. It can also feed other animals, if heated in such a way that it retains the proper enzymes.

Students like Chandler and Pettis are still experimenting with the machine to find its optimum production. Important factors include whether the press plate or the feed nozzle should be heated, how large the nozzle should be and how fast the machine should process the seeds. On a farm, the machine could eventually pay for itself through savings on animal feed, oil and travel time, Olson said.

“Devices like these could support a typical dairy farm… [but] very few farmers have them yet,” Olson said. “It’s a good engineering experiment to solve the world’s problems, on absolutely zero budget.”

The ag engineering department is also using leftover oil from Dining Services. The seed press is the newest part of their plan to produce bio-diesel fuel.