Featured Research

from universities, journals, and other organizations

Simple Filter Delivers Clean, Safe Drinking Water, Potentially To Millions

Date:
March 16, 2009
Source:
University of North Carolina at Charlotte
Summary:
As an efficient, inexpensive, low-tech way to treat water, new research could bring clean, safe drinking water to potentially millions upon millions of people.

Dr. James Amburgey works with student Alice Wang on the rapid sand filter prototype.
Credit: Image courtesy of University of North Carolina at Charlotte

As an efficient, inexpensive, low-tech way to treat water, Dr. James Amburgey’s research could bring clean, safe drinking water to potentially millions upon millions of people.

Related Articles


Simplicity is the primary objective of the rapid sand filter system Amburgey is developing. “The idea is to make it as simple as possible,” he said. “All that is needed is some PVC pipe, sand and inexpensive treatment chemicals. The only way to practically deploy a system to the people of less developed countries is for it to be inexpensive and simple.”

Amburgey, an assistant professor of Civil and Environmental Engineering, specializes in drinking and recreational water treatment. He has done work in the past with slow sand filters, but his latest research with rapid sand filters is demonstrating the ability to clean water much more effectively and 30 to 50 times faster.

“One significant challenge with sand filters is in removing Cryptosporidium oocysts,” Amburgey said. “One ‘crypto’ is five microns in diameter, but the gaps between grains of sand are approximately 75 microns. So, we have to get the crypto to stick to the sand grains.”

To achieve this, Amburgey has developed a chemical pretreatment scheme based on ferric chloride and a pH buffer that is added to the water. In its natural state, Cryptosporidium is negatively charged, as are sand grains, so they repel one another. The chemical pretreatment changes the Cryptosporidium surface charge to near neutral, which eliminates the natural electrostatic repulsion and causes it to be attracted to and stick to the sand grains via van der Waals forces.

In research using a prototype of this system in his lab, Amburgey and his students have done preliminary tests on waters from local rivers, creeks and wastewater treatment plants. Their results are typically greater than 99 percent removal for Cryptosporidium-sized particles.

“A common problem in drinking water treatment facilities is that changing water quality requires changes in the chemical pretreatment dosages,” Amburgey said. “Our tests, so far, have shown that this system utilizing only a single set of chemical pretreatment dosages is effective on all waters tested to date.”

Another advantage of the system is that it can be adapted by using local sands or crushed rock that are indigenous to a particular region of the world.


Story Source:

The above story is based on materials provided by University of North Carolina at Charlotte. Note: Materials may be edited for content and length.


Cite This Page:

University of North Carolina at Charlotte. "Simple Filter Delivers Clean, Safe Drinking Water, Potentially To Millions." ScienceDaily. ScienceDaily, 16 March 2009. <www.sciencedaily.com/releases/2009/03/090309211938.htm>.
University of North Carolina at Charlotte. (2009, March 16). Simple Filter Delivers Clean, Safe Drinking Water, Potentially To Millions. ScienceDaily. Retrieved January 27, 2015 from www.sciencedaily.com/releases/2009/03/090309211938.htm
University of North Carolina at Charlotte. "Simple Filter Delivers Clean, Safe Drinking Water, Potentially To Millions." ScienceDaily. www.sciencedaily.com/releases/2009/03/090309211938.htm (accessed January 27, 2015).

Share This


More From ScienceDaily



More Matter & Energy News

Tuesday, January 27, 2015

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Cablevision Enters Wi-Fi Phone Fray

Cablevision Enters Wi-Fi Phone Fray

Reuters - Business Video Online (Jan. 26, 2015) The entry by Cablevision and Google could intensify the already heated price wars for mobile phone service. Fred Katayama reports. Video provided by Reuters
Powered by NewsLook.com
Hector the Robot Mimics a Giant Stick Insect

Hector the Robot Mimics a Giant Stick Insect

Reuters - Innovations Video Online (Jan. 26, 2015) A robot based on a stick insect can navigate difficult terrain autonomously and adapt to its surroundings. Tara Cleary reports. Video provided by Reuters
Powered by NewsLook.com
Raw: Pilot Uses Full-Plane Parachute in Crash

Raw: Pilot Uses Full-Plane Parachute in Crash

AP (Jan. 26, 2015) A pilot en route to Hawaii crashed his single-engine plane into the Pacific Ocean Monday and escaped safely thanks to the use of a full-plane parachute. US Coast Guard video captures the dramatic landing. (Jan. 26) Video provided by AP
Powered by NewsLook.com
Scientists Model Flying, Walking Drone After Vampire Bats

Scientists Model Flying, Walking Drone After Vampire Bats

Buzz60 (Jan. 26, 2015) Swiss scientists build a new drone that can both fly and walk, modeling it after the movements of common vampire bats. Jen Markham (@jenmarkham) has the story. Video provided by Buzz60
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins