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Micro Bubbles: A Trump Card for Quick Water Purification

Micro Bubbles: A Trump Card for Quick Water Purification

As the motor of a small device is activated the water in the aquarium slowly turns a milky white. Upon closer inspection one can notice that the cloudiness of the water is actually from the extremely fine bubbles that Associate Professor Yoshioka Shuya calls “Micro Bubbles” and uses to purify drainage water and mud.

During the Great East Japan Earthquake many fish processing plants and other facilities along the eastern coast were heavily damaged. Amongst these, if water processing plants are damaged and drainage is no longer possible, reconstruction and restoration becomes that much more difficult. This is because the restoration of the tanks and drainage pipes is expensive and time consuming. Saying that, it is not possible to simply discharge the built up sewage water as this would simply cause secondary environmental disasters. But this is precisely where Associate Professor Yoshioka’s “Micro Bubbles” are expected to work their magic.

Associate Professor Yoshioka explains that “microorganisms are invigorated by the oxygen found in water and feed off of potentially harmful organic matter such as animal corpses, etc. Furthermore, iron, manganese and other metals can be oxidized and then deposited at the bottom of the water which helps purify the water of the metallic contaminants. So it is clear that water possesses a natural ability to purify itself, but when the water becomes stagnant due to power failure or damages to the facility oxygen is depleted and this natural ability drops at a remarkable rate. It is possible to inject high pressured oxygen into the water, but this requires a large machine and a power generator, plus the bubbles produced quickly rise to the surface which greatly reduces their effectiveness. However, by utilizing the smaller micro bubbles all of these problems are solved.”       

These “Micro Bubbles” that turned the water milky white are only 50 microns (1/20th of a millimeter) in diameter. By being so small the bubbles loose their buoyancy and are unable to move in the water, allowing them to remain where they are most effective. These micro bubbles are produced by a device that “finely shreds the air,” but unlike previous methods it is small and can be run from a regular household power outlet.

This device has already shown results in water purification tests at a dam in central Miyagi prefecture and is scheduled to be installed in fish and food processing plants, as well as sewage processing facilities to assist with sewage treatment efforts. “This process will not change sewage to drinking water, but will purify it to a level where it is safe to be discharged. From there it can be sent to a drinking water purification plant, making it possible for developing countries to utilized pre-existing lakes and marshes for new sources of clean drinking water. Creating new dams for drinking water is convenient, but causes a great strain on the local environment. Also, as the device is small and portable it could be stored for local disaster prevention and transported to local disaster areas via a small truck to be used to maintain water purification for the local people” stated the professor.           



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Keywords:micro bubbles, water treatment,