| 摘要 |
<p>The invention relates to an up-flow filtration apparatus and method of using such apparatus. The up-flow filtration apparatus comprises of a tank, a plurality of screens and a filtration medium containable between the screens. The filtration medium preferably has a specific density equal to or lower than the specific density of the liquid being filtered, so as to cause the filtration medium to float in the liquid. In use, liquid to be filtered rises upwardly in the tank through a lower screen via apertures defined therein and compresses the filtration medium, under a buoyancy force, against an upper screen. The liquid is forced upwardly through the interspaces between the filtration medium, causing impurities in the liquid to be trapped in the filtration medium. Filtered liquid passing through the filtration medium passes through apertures defined in the upper screen and out of the tank via an outlet. The filtration apparatus is cheap to build and to operate, is modular and is erectable at or near the location at which the filtered liquid is required.</p> |
