Bubbles could help remove trash from rivers.
There is a creek behind Dakota Perry's house in Mobile, Alabama. She noticed plastic bags, bottles and cups there. Trash was strewn across the water and collecting along the shoreline. Some might opt for a community trash pickup, however, Dakota wondered if there was a better way.
Dakota is 15 years old and is a sophomore at W.P. Davidson High School in Mobile. She presented her solution to pollution in a science fair. Pollution is the addition of harmful materials to the environment. The fair was called the Regeneron International Science and Engineering Fair (ISEF) and it was held in May in Atlanta, Georgia.
Building The Bubbles
Dakota's idea was inspired by the Dutch Great Bubble Barrier in Amsterdam, Netherlands. Like the Dutch system, her backyard system would send a curtain of bubbles up from the river bottom to gather trash and move it to the side of the creek. Dakota challenged herself to make that concept completely green. Hers would run entirely on hydropower and solar energy. Hydropower is energy from moving water. Solar energy is energy from the sun.
In Dakota's design, a curtain of bubbles would span the river in a diagonal line. Floating trash would be stopped by the curtain and pushed toward the shore. There, a conveyor belt run by a solar-powered battery, would collect the debris. The belt would transport trash to a dumpster.
Fish can swim right through the bubbles. Like in a fish tank, oxygen released by the bubbles would help keep the water well aerated, or full of air.
Testing With Trash
Dakota's system relies on an air compressor. This is a device that presses air into a small space so it can be used under high pressure. The compressor sends air through a plastic pipe with rows of tiny holes. Air escaping through those holes bubbles to the surface. It creates what looks like a curtain. Dakota plans on using the power of the creek to run the air compressor in the future. It would get its energy from water wheels connected by a pulley system that would power the compressor. That will be the next phase of her project.
For now, Dakota has focused on fine-tuning the bubble curtain. That was the most important part to figure out. "For the bubble system to actually work and actually collect the trash," she explains, "I have to know how much pressure the air compressor is supposed to push out."