Featured Research

from universities, journals, and other organizations

Simple way to remove mud from drinking water

Date:
May 1, 2012
Source:
Michigan Technological University
Summary:
It's easy to purify clear water: just put it in transparent bottles for a few hours in the sun. Muddy water -- like that found in the developing world -- is another issue. Now researchers have devised a simple way to get the mud out.

Leaving bottles of water in the sun kills pathogens--but only if the water is transparent. Michigan Tech's Joshua Pearce has devised a simple way to clarify water, so even muddy water could be made safe for drinking.
Credit: SODIS Eawag photo

Nearly 80 percent of disease in developing countries is linked to bad water and sanitation. Now a scientist at Michigan Technological University has developed a simple, cheap way to make water safe to drink, even if it's muddy.

It's easy enough to purify clear water. The solar water disinfection method, or SODIS, calls for leaving a transparent plastic bottle of clear water out in the sun for six hours. That allows heat and ultraviolet radiation to wipe out most pathogens that cause diarrhea, a malady that kills 4,000 children a day in Africa.

It's a different story if the water is murky, as it often is where people must fetch water from rivers, streams and boreholes. "In the developing world, many people don't have access to clear water, and it's very hard to get rid of the suspended clay particles," says Joshua Pearce, an associate professor of materials science and engineering. "But if you don't, SODIS doesn't work. The microorganisms hide under the clay and avoid the UV."

Thus, to purify your water, you first have to get the clay to settle out, a process called flocculation. Working with student Brittney Dawney of Queen's University in Ontario, Pearce discovered that one of the most abundant minerals on Earth does this job very well: sodium chloride, or simple table salt.

Salt is inexpensive and available almost everywhere. And it doesn't take very much to make muddy water clear again.

"The water has a lower sodium concentration than Gatorade," Pearce says. This would still be too much salt to pass muster as American tap water, but American tap water is not the alternative.

"I've drunk this water myself. If I were somewhere with no clean water and had kids with diarrhea, and this could save their lives, I'd use this, no question," he says.

Salt works best when the suspended particles are a type of clay called bentonite. The technique doesn't work as well with other kinds of clay. However, by adding a little bentonite with the salt to water containing these different clays, most of the particles glom together and settle out, creating water clear enough for SODIS treatment.

Pearce and Dawney are running more tests on water containing various types of clays, and they are also investigating different soil types across Africa to see where their methods might work the best.


Story Source:

The above story is based on materials provided by Michigan Technological University. Note: Materials may be edited for content and length.


Journal Reference:

  1. Brittney Dawney and Joshua M. Pearce. Optimizing the solar water disinfection (SODIS) method by decreasing turbidity with NaCl. Journal of Water, Sanitation, and Hygiene for Development, June 2012 DOI: 10.2166/washdev.2012.043

Cite This Page:

Michigan Technological University. "Simple way to remove mud from drinking water." ScienceDaily. ScienceDaily, 1 May 2012. <www.sciencedaily.com/releases/2012/05/120501134315.htm>.
Michigan Technological University. (2012, May 1). Simple way to remove mud from drinking water. ScienceDaily. Retrieved August 20, 2014 from www.sciencedaily.com/releases/2012/05/120501134315.htm
Michigan Technological University. "Simple way to remove mud from drinking water." ScienceDaily. www.sciencedaily.com/releases/2012/05/120501134315.htm (accessed August 20, 2014).

Share This




More Earth & Climate News

Wednesday, August 20, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Charter Schools Alter Post-Katrina Landscape

Charter Schools Alter Post-Katrina Landscape

AP (Aug. 20, 2014) Nine years after Hurricane Katrina, charter schools are the new reality of public education in New Orleans. The state of Louisiana took over most of the city's public schools after the killer storm in 2005. (Aug. 20) Video provided by AP
Powered by NewsLook.com
Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

Green Power Blooms as Japan Unveils 'hydrangea Solar Cell'

AFP (Aug. 19, 2014) A solar cell that resembles a flower is offering a new take on green energy in Japan, where one scientist is searching for renewables that look good. Duration: 01:29 Video provided by AFP
Powered by NewsLook.com
Disquieting Times for Malaysia's 'fish Listeners'

Disquieting Times for Malaysia's 'fish Listeners'

AFP (Aug. 19, 2014) Malaysia's last "fish listeners" -- practitioners of a dying local art of listening underwater to locate their quarry -- try to keep the ancient technique alive in the face of industrial trawling and the depletion of stocks. Duration: 02:29 Video provided by AFP
Powered by NewsLook.com
Wildfire Hits California's Angeles National Forest

Wildfire Hits California's Angeles National Forest

Reuters - US Online Video (Aug. 17, 2014) A wildfire sweeps across the Angeles National Forest prompting campers to quickly leave as officials began evacuating the area -- local media. Gavino Garay reports. Video provided by Reuters
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:
from the past week

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