LEXINGTON, VA - As part of an ongoing effort to help a village in South America, a group of VMI cadets is spending the summer working to find ways to help the people there purify their water. Their solution may surprise you -- llama manure.
From South America to Haiti and beyond, VMI's "Engineers Without Borders" program sends cadets and faculty to some of the most impoverished areas in the world to lend a helping hand. One of those places is a small village in the mountains of Bolivia called Pampoyo.
"Because of all the mining there, they have heavy metal contamination in their streams," said Major Tim Moore, an Associate Professor of Engineering at VMI and faculty sponsor of Engineers Without Borders. "They drink directly from those streams. And because of that they end up with a lot of health problems."
Moore leads a group of students to Pampoyo every year and the primary focus of those trips has been giving the people there access to clean water.
"So one of the ideas that came to mind was hey, what about carbon filtration?" said Moore. "We know that works. We use carbon filtration in Brita filters."
To make that work, Moore says, they need to find a source of carbon that's readily available in Pampoyo. Because of the elevation, the usual suspects like plants and other woody material won't grow there -- but one thing villagers do have a lot of is llama manure.
This summer it's cadets Amber Joyner and Alexandria Gagnon's job to figure out how to take llama manure and turn it into a working filtration system.
"I did not know that you could do that," said Joyner. "But I think it's absolutely amazing that something that's so readily available in that country is something that can help save lives and can promote health."
They burn the manure at 350 degrees Celsius for several hours to kill any bacteria or other harmful organisms it may contain. Then, they grind up what's left -- a carbon-rich material called biochar -- and add it to the water.
"A really small amount can clean a whole liter of water," said Gagnon.
After they mix in the biochar, they place the bottles of water on a machine that shakes them for 24 - 48 hours. They then pour the water through another filter to remove the biochar -- and end up with clean water.
"I really think this is the quintessential definition of sustainability," said Moore. "Cleaning water with manure, I think that's amazing you can do that."
Using this process, they've been able to remove more than 90 percent of the metal in water samples they've contaminated with iron, copper, and lead. The next step, they say, is to take what they've learned in the lab and figure out how they can replicate it in Bolivia.
"They don't have a $10,000 oven. We do," said Gagnon. "So we need to figure out a way they can do this themselves and then how are they going to filter the carbon out of the water."
They hope to have those questions answered before they return to Pampoyo next spring.
They say they still have to run some tests on the filtered water before they drink it themselves -- but they believe they are very close to that point.
Another cadet is working on a different project that involves llama manure. Matthew Harvey, who has traveled to Pampoyo, says another big issue there is nutrition. Because of the elevation and terrain, few food items can grow there -- so he's working on a system he hopes can change that.
It starts with a large tank full of fish. The water in the tank has high levels of ammonia because of the fish feces floating around in it. That water is then pulled through a tube up to another tank that sits above a bed of plants. Once an hour, it waters them.
Harvey says plants naturally break down the ammonia into nitrogen and nitrates they use to grow. Because the plant beds use rocks instead of soil, the water trickles down through them and eventually back down into the fish tank. The now nitrogen-rich water is beneficial to the fish. The cycle then repeats itself.
Villagers would also be able to eat the fish.
As part of his research, Harvey is also looking at the effects the llama manure bio-char has on the plants when its scattered around them.
He says the goal is to build one of these systems when Engineers Without Borders returns to Pampoyo next spring.
"If I can do something fun like this, learn stuff, and it's benefiting people, the smiles they have on their faces, the thank you's, and the hugs are more than enough to make it all worth it," said Harvey.
Moore also hopes to get the research of all the cadets published in an engineering journal this fall.