I want seminar report on hyper sound water purifying system

Sound waves could provide a greener way to make tap water taste better.

Ultrasound can make bubbles in the water that could clean ceramic filters quickly and cheaply, say Linda Weavers and colleagues at Ohio State University, Columbus1. When the bubbles burst, they release energy that makes small, but fiercely powerful, jets of water that clean the surface of the filter and clean the debris.
Most municipal water treatments rely on slow, environmentally risky chemical purification. A greener and more efficient alternative is to use membrane filters. These have so tiny pores that they sift out particles and microorganisms as small as viruses; But they are easily obstructed. Dirty filters should be removed and scrubbed or replaced, slowing down the process and increasing its cost.

Ultrasonic cleaning could make membrane filtration the rule rather than the exception, the Ohio team hopes. "If you left the ultrasound running, you could clean the filter while it is still in use, and prevent it from getting stuck in the first place," says Weavers, who believes that, extended, the process could replace chemical water purification.

Philip Brandhuber of McGuire Environmental Consultants in Denver, Colorado, specializing in membrane filtration for drinking water, agrees to say he is pleased to see this "entirely new approach to the scale problem."

A potential problem is that bursting bubbles could damage filters. Ceramic filters are hard and heat resistant. But ultrasonic cleaning could degrade cheaper, more frequently used polymer membranes, says Menachem Elimelech, an environmental engineer at Yale University.

Others think that the benefits of switching to ceramic filters would justify the costs. Tom Allsop, superintendent of the Pinesdale, Montana Water Department - whose plants use sand and paper filters - says he would skip the opportunity to install a combination of ultrasound and ceramic. "If it works as well as they say, it would save us huge amounts of money each year," says Allsop.

Brandhuber doubts that Allsop's enthusiasm is representative of the drinking water industry as a whole. The industry is inherently conservative, says Brandhuber, concerned about public health and publicly funded. Before municipal plants can invest, the technology must undergo a much more rigorous research, he adds.

The group of weavers intends to do just that. They are planning more tests to determine how well the bubbles remove different contaminants and how different types of filters support sound-induced descaling.