Tuesday, July 15, 2008

Water Purification: Particle-Exclusion Phenomenon

An entirely new way of purifying water has been discovered by scientists in the US. The technique is based on the discovery that water-attracting materials seem to repel impurities, leaving a layer of pure water near their surface.

In 2003, Gerald Pollack and his colleagues at the University of Washington, Seattle, discovered a process known as the "particle-exclusion phenomenon".

They found that particles dissolved in water naturally move away from a hydrophilic, or water-loving, surface, leaving pure water behind.

What was really surprising was quite how far the particles would move – up to several tenths of a millimetre. This is much further than predicted by conventional theories.


The article goes on to state that this process can remove 97% of man-made latex contaminants and between 70-90% of clay and soil. It does this through a process of separating the pure water from the contaminated water by utilizing two pipes: one that syphons near the hydrophilic surface while the other syphons from the center. The drawback is that it currenlty only produces 15 milliliters per hour, but Pollack thinks this bottle neck can be overcome by combining thousands of these hydrophilic tubes together.

You can read more here.

Some questions:
-Do you see potential in this method?
-Could this technology work in deveoloping countries to produce cheap, clean water?
-What do you see as the drawbacks?
-Do you think that we take water for granted?
-Could this technology be used for Mars settlements?

1 comment:

Josh said...

I think they are crazy! What was wrong with the old method of purifying water? Why do we need to even purify the water? At least for Americans we should be able to drink out of the sink like we did for years before "pure mountain spring water" came in put "normal water to shame.