U of A Team Creates Water Purification System

03.16.11

A U of A WERC design team submitted an original water purification system to a New Mexico Design Competition this week. In preparation for the April 3 competition, the team presented their system to members of the U of A EWB chapter, who will be doing similar work in Belize this spring.

WERC is a consortium for environmental education and technology development, according to the University of Arkansas chemical engineering department website. The New Mexico Design Competition includes design criteria of an inexpensive, portable water purification system that processes 3,000 gallons of water per day.

The system brings the water through a sand filter, and then a man-powered treadle pump brings it up through a micron bag filter with activated carbon.

The device can pump from any water source and purify 3,000 gallons of water per day. “We operated the system, pumping from a creek 10 feet below it. It reached 10 PSI, with a constant PSI of 8,” he said. “It’s not hard or tiresome to operate at all.”

To produce enough filtered water for a community—about two 1500 gallon tanks, the treadle pump requires two people to power it for three hours. Although it’s easy to operate, WERC team members doubt children or smaller-frame adults could operate it.

“It pumps 15-20 gallons per minute and is simple to construct,” said a WERC team member.

The filtration system has a submersible sand filter and one micron bag, which benefit from increased pressure levels. “The pressure we need can be gained by height or by putting it under water.”

The purification system uses few materials: mostly two-by-fours, 4-inch PVC pipe, valves, leather seals and a weekly filter change ($3). To disinfect the water, it uses a quart of bleach for every 1500 gallons.

“After adding the bleach, let it stand for 30 minutes, the chlorine smell shows that it’s completely disinfected, by EPA guidelines,” he said. “Bleach is safe to drink at given concentration by WHO.”

The group plans to use the system in a trip to Haiti later this year.
“We’re working with the honors college to implement it,” he said.

If you’d like to get involved with the exciting work of Engineers Without Borders, but can’t afford the spring trip to Belize, look forward to any of their local service projects coming up:

April 8-9 AiCHE conference on UA Campus, free lunch for volunteering to put registration materials together and serving lunch.

April 16 Building Together group: “Rebuilding Day”

April 21 Leverett Elementary Science Club: leading a lesson on structures on sand and an on-paper activity