Graduate student invents DIY reverse osmosis system for birch sap concentration

SNRAS Master's International student and OneTree service learner Tricia Kent has created a method of concentrating birch sap that will provide a boost to K-12 science education in Fairbanks.

As part of her research and service learning commitment, Kent is working on a reverse osmosis system that will be used to concentrate birch sap for the OneTree Alaska "Tapping into Spring" program.

Kent's undergraduate focus at Rensselaer Polytechnic Institute was in materials science, and she has worked in fabrication technologies and as a metallurgical engineer for Chromalloy. She switched to natural resources management as her M.S. focus, and in March she moves to Mexico to serve in the Peace Corps. She expects to be engaged in environmental education while also working on some aspect of non-timber forest products research for her master's project. She will begin training in Queretaro, Mexico, March 20.

Tricia Kent takes measurements in the UAF arboretum. (Photo by Diane Hunt)

"Trish is a great example of what service learners provide in a higher education context," said OneTree Alaska Director Janice Dawe. "She is someone who can take their academic training -- in Trish's case, a combo of materials science, horticulture and natural resources management -- out of the classroom and into K-12 classrooms and the community."

"The DIY reverse osmosis that Trish is building is an innovation for us," Dawe said. "It will greatly enhance the processing of birch sap by concentrating the sap sugar and removing a large percentage of the water in the sap, before it's boiled down to syrup. Trish is coming back to Fairbanks in late January through mid-February to complete work on the RO unit and train the rest of the OneTree Alaska team in its use. We're also talking with the engineering senior design seminar, in hopes that one of the students will choose to adopt the project as their senior capstone project."

Tapping into Spring is a program that engages hundreds of K-12 children in the Fairbanks North Star Borough School District each spring with tapping trees for sap. The students will get to see the RO in action on field trips to UAF University Park Building to process their sap.

"We also expect backyard syrup makers may be interested in the cost savings and labor reduction represented by this DIY reverse osmosis, which is being built for less than $500," Dawe explained. "No plans have been made at this point to work with local syrup-makers on this; we need to complete the first season of sap collection with the RO."

Kent chose to work on this project because of her interest in non-timber forest products (materials that can be harvested from a forest that are not used for lumber). "This is an extensive list, but one that is particularly applicable to our boreal forest is birch sap," Kent said.

Last summer she visited the East Coast where the maple syrup industry is booming and talked with farmers and maple syrup makers to learn more about the process and figure out a way to apply this knowledge to birch sap.

"I hope that growing the Tapping into Spring project by building an RO unit will allow us to process more sap than in the past, and provide new and exciting science and engineering lessons for our classrooms," she said.

"We have had issues with the birch sap evaporator aspect of the Tapping into Spring program," Kent stated. "I originally was going to get an evaporator for the project and have it running off of steam from the UAF power plant. However, between the huge demand for custom-made evaporators and the renovations to the power plant coming in the next couple of years, the evaporator project got pushed to the back burner. The RO unit was a smaller project that could still provide interactive learning opportunities for our OneTree students."

Related video:

Watch a clip of Tricia Kent describing her DIY reverse osmosis machine.