Media Filters
Media filters are filters based on one or more media. Usually this medium consists of filter sand, but the filling of high bed filters is frequently supplemented with, for example, anthracite and/or gravel.
Media filters are divided into sand filters and high bed filters. The difference between a sand filter and a high bed filter is the height of the filter and thus the height of the filter media bed. A media filter has a relatively simple working principle: the water enters the top of the filter on a diffuser plate, which divides the water horizontally across the surface. After that the water goes down through the medium. In this case, the water must move around a medium grain every time, through small openings.
The dirt remains on the media grains and the water moves downwards. Above the bottom a floating bottom plate with filter caps is situated that holds the sand but allows water to pass. Media filters have a huge depth filtration, which allows a very good filtration depending on the flow rate. A media filter is cleaned by rinsing the water at the correct speed in the opposite direction, with the dirt being detached from the media and removed with the water.
The filtration of a media filter can be increased by a lower flow rate and by applying a higher filter bed, a high bed filter. A sand filter is the most standard filter solution of all media filters, useful for all kinds of applications. A high bed filter is ideally suited as a prefilter for example a UV disinfectant.
