Drinking Water Treatment Multimedia Pressure Filter

Pressure water treatment filter is a RSF contained under pressure in a steel tank, which may be vertical or horizontal, depending on the space available. Similar to gravity filters, the media in pressure filter is usually sand or a combination of media also called multimedia filters. Filtration rates are similar to gravity filters. The below figure shows the details of vertical and horizontal pressure water treatment filters. 
These filters are commonly used for iron and manganese removal from groundwater, which is first aerated to oxidize the iron or manganese present, then pumped through the filter to remove the suspended material. Pressure filters are also used in swimming pool for recirculation water treatment.
Regardless of the method of control, the water filter eventually fills with suspended material. At some time, usually after 15 to 30 hours, it will need to be backwashed similar to rapid sand filter to clean the media and restore the normal rate of filtration.


 

• Fine gravel: 1-20mm
• Silica sand of various roughness: 0.4-2.5mm
• Active charcoal: is used for absorption of chlorine and other mineral substances
• Anthracite: is used in two-layer or multi-layer filtration of drinking water in connection with sand - the addition of anthracite guarantees a longer filter lifetime, it facilitates a larger filtration through-flow and reduces sand contamination
• Catalytic mediums [YAMLOX®]: are used to remove iron and manganese from drinking water
• Semi-burnt Dolomite limestone: is used to reduce water acidity

The filtration bed can be formed by one layer or more layers of various filtration materials. Filtration sand lifetime during a proper washing of filters oscillates around 8 years on a standard basis.

The entire automatic process of filtration and back washing of filters is controlled by a central control unit. The control unit makes it possible to set filter washing on the basis of time, pressure difference or filtered water quantity.

Filters are washed, on a standard basis with raw water or with treated water from reservoirs.

Filters are fitted with a filtration inter-bottom with jets. The jets are made of the ABS material and make it possible to wash with water or both water and air. In the case of the filling height not exceeding 1500 mm, the water flushing process is fully sufficient.

Pressure filters are made of carbon steel with a protective anticorrosion coating with epoxy resin in the RAL 5010 [gentian blue] or 5012 [light blue] colour shade. The coating meets the conditions of hygienic harmlessness for contacts with drinking water.