Simple Filter Delivers Clean, Safe Drinking Water — Potentially to Millions

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.

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.

Media Contact

Paul Nowell Newswise Science News

More Information:

http://www.uncc.edu

All latest news from the category: Ecology, The Environment and Conservation

This complex theme deals primarily with interactions between organisms and the environmental factors that impact them, but to a greater extent between individual inanimate environmental factors.

innovations-report offers informative reports and articles on topics such as climate protection, landscape conservation, ecological systems, wildlife and nature parks and ecosystem efficiency and balance.

Back to home

Comments (0)

Write a comment

Newest articles

Results for control of pollutants in water

Brazilian scientists tested a simple and sustainable method for monitoring and degrading a mixture of polycyclic aromatic hydrocarbons, compounds present in fossil fuels and industrial waste. An article published in the journal Catalysis…

A tandem approach for better solar cells

Perovskite-based solar cells were first proved in 2009 to have excellent light-absorbing properties of methylammonium lead bromide and methylammonium lead iodide, collectively referred to as lead halide perovskites or, more…

The behavior of ant queens is shaped by their social environment

Specialization of ant queens as mere egg-layers is reversible / Queen behavioral specialization is initiated and maintained by the presence of workers. The queens in colonies of social insects, such…

Partners & Sponsors