Sunday, January 16, 2005

Scientist Brings Water To World - UV Disinfectant??

Yesterday, I was at a training on Turning Air Into Water. I found this article in my email today. which I like to share with all out there.

What I show is 2 UV filters each with 2 UV Bulbs to disinfect the bacteria's in the incomming water. But their present capacity is 8 Gallon a days
producing drinking water from the Air.

Here, below news from Dr Gadgil work in University of California is about the UV disinfectant at a cost of 5 cents for one tons of Water &
it use 6,000 times less power then the market available UV system.

These certainly is a good news. However, the water must be pipe in & no family would be using the tons of water per day. In additions, the bacterias built in the pipe before it reaching building or home are age old.

In my opinion, there must be more sensible for a domestic version of these UV filter at say 1/10 of a cent for office & home. & also the energy saving feature would greatly benefits all.

From my research on water, if water is filtered & then drink after some time, the water born bacterias would give birth again. So the quality of water is not maintained. THerefore, I don't endorse those storage tank type of Water Filtration system.

Scientist Brings Water to World
Environmental physicist’s work to purify water with ultraviolet light featured in new documentary movie

BY BERNICE NG Wednesday, November 22, 2000

Through the use of beams of ultraviolet light, a Berkeley scientist has developed a cost and energy efficient method to clean polluted water in developing countries, and the success of his work has landed him a role in a soon-to-be-released film.

Since completing his doctorate work at UC Berkeley, Lawrence Berkeley National Laboratory environmental physicist Ashok Gadgil has devoted his research to energy efficiency. His success in developing a system to provide clean water to billions of people around the world has made him one of seven scientists featured in the upcoming movie "Me and Isaac Newton."

Gadgil is a scientist in the Environmental Energy Technologies Division and invented UV Waterworks — a battery-powered water purification device that has been used widely in developing countries where a lack of clean water has posed dire health problems to people. His machine has also been credited to saving lives in the aftermath of natural disasters such as devastating hurricanes.

The simple, inexpensive system disinfects polluted water by shining down rays of ultraviolet light. The purification device uses 6,000 times less energy than the energy required to boil water.

In the film, directed by Michael Apted, who has directed a number of documentaries as well as last year's James Bond epic, "The World is not Enough," Gadgil tells of his upbringing in Bombay, where he grew up in the midst of poverty and disease.

The movie, which captures the lives of seven different scientists, is scheduled for release in Berkeley on Dec. 8.

"(The movie) focuses on what motivates scientists to do science and gets under the skin to see what makes them tick," said Gadgil, who received his doctorate degree in physics from UC Berkeley. "I was interested in physics and science for as long as I remember."

It was during his work on campus when Gadgil became interested in studying the kind of impact humans have on the environment.

Gadgil, who noticed that the rate of resource use per capita is much higher in the United States than in developing countries, said he was disturbed to find out the environmental damage that would be needed in order to raise the standard of living in other countries to the level of that in America.

"You can't raise the standard of living of most of the world to one half of the United States without totally destroying the environment," he said. "The world cannot bear that burden. In some sense, it was a bitter conclusion."

According to Gadgil, improving the standard of living entails the burning of carbon dioxide, the release of toxic chemicals and many other processes that lead to environmental destruction.

This realization motivated Gadgil to study energy efficiency and his research focuses on developing methods to use the least amount of energy to create the greatest amount of positive change. Gadgil said he strives to figure out how to achieve satisfactory energy services such as heating and lighting, but through the use of substantially less energy.

"Energy is the major single environmental burden," he said. "Other than warfare, it's the worst thing we can do."

In the movie, Apted highlights the portion of Gadgil's research that focuses on trying to tackle the lack of availability of drinking water in countries such as India, South Africa and Honduras.

"Anybody who travels is very aware (of the difficulty of finding clean water)," he said. "But it's a reality of everyday life for more than a billion people."

According to Gadgil, approximately 400 children die per hour as a result of contaminated water.

While the solution to this problem is not complicated in terms of the method to kill bacteria, the most difficult obstacle in cleaning the water lies in the practicability and ability to provide the machinery to developing countries, he said.

"This is entirely preventable," Gadgil said. "It doesn't take rocket scientists."

The small-scale, energy-efficient and low-maintenance design of Gadgil's water purification system has made it a uniquely affordable and effective device. The machine provides many communities in developing nations with readily accessible, disinfected drinking water.

What drives Gadgil to work each day is the continual broadening and deepening of the field he is interested in and his concern for the future of the planet, he said.

"Where are we headed and what are we going to leave for our future generations?" he said. "Are we going to stick them with problems?"

Gadgil said he is concerned that future inhabitants of Earth will find the planet so "disastrously unsustainable" that they would look back and say "my parents and grandparents essentially wasted the Earth."

For years, Gadgil sent literature to his colleagues in India about the importance of providing clean water. It was not until an outbreak of cholera that killed 10,000 people in a single state of India in May of 1993, however, that Gadgil decided to get personally involved in the project.

The 1993 outbreak was caused by a mutant strain of bacteria that exhibited a different protein on its surface. The vaccines at that time were not capable of destroying the bacteria. Because the process of developing a new vaccine would take at least two years, Gadgil decided that he needed to begin to take action.

"That summer, I decided that we can't just keep talking about water," he said.

Gadgil and one of his students found that they could develop a device to disinfect drinking water by using ultraviolet light. Their method could produce clean water for what looked like less than a penny per ton of water.

Exposure to ultraviolet light successfully mutates the DNA of bacteria and renders the water-borne pathogens incapable of reproducing. Precise doses of UV doses can deactivate bacteria by disturbing the replication process necessary for proliferation, or even kill the microorganisms altogether.

In addition to low cost, the scientists also had to tackle ecological and mechanical problems.

"We needed to provide affordable water with low failure rates, no moving parts," he said.

The device was designed, built and tested at the lab in Berkeley. SInce then, it has gone through a number of redesigns for improvement and has also been used in field tests in countries around the world.

Revisions have included the introduction of additional safeguards such as increasing the dose of ultraviolet light to increase the amount of bacteria killed as well as regulatory precautions such as making sure that water cannot enter the disinfecting machine unless the proper voltage supply is available.

The danger of an insufficient voltage is that contaminated water could run through the machine, but not be disinfected.

"The machine will cut off if the voltage goes outside of an accepted band," Gadgil said.

Currently, the machine is capable of disinfecting one ton of water per hour at a cost of approximately four to five cents per ton.

The benefits of the low cost and time efficiency of using ultraviolet light make it a good candidate for disinfecting water in developing countries.

Although boiling water is the most effective disinfecting approach, the time and labor involved is not sufficient enough for the demands for water for cooking, drinking and proper sanitation, scientists said.

The reason ultraviolet light is effective in developing countries is that the water, unlike that in the United States, is overwhelmed by large amounts of contamination, versus the miniscule levels in developed countries.

Gadgil's machine is designed to disinfect water directly at its point of use.

Field tests conducted on the machine to measure its performance in Honduras, the Philippines, South Africa and Guererro, Mexico resulted in positive feedback, he said.

"There was some evidence from health clinics that the incidence of diarrhea has dramatically dropped," Gadgil said. Read More....
The Daily Californian

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