| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a water purification equipment excellent performance to remove the solid content attached to the surface of a membrane element as well as capable of sufficiently preventing damages on the surface of the membrane element, and a method for cleaning the membrane element. SOLUTION: The water purification equipment 1 is provided with a treating tank 11 to which a water to be treated is supplied, a flat membrane 33 which is immersed in the water W to be treated to obtain a treated water by the membrane filtration of the water to be treated, a bubbling equipment 25 generating air bubbles 3 in the treating tank 11 and a floating solid 2 capable of floating on a gas-liquid interface in the treating tank 11. At the time of cleaning a flat membrane 33, the solid content attached to the surface of the membrane is efficiently cleaned by transferring the gas-liquid interface within a range between both up and down ends of the flat membrane 33 and vibrating the floating solid 2 to strongly rub with the flat membrane 33. The damages on the surface of the membrane are prevented because the floating solid 2 comes into contact with the surface of the membrane only at the time of washing.</p> |
