A bag filter works according to the principle of a microfiltration. Bag filters can be used for large amounts of water. The water enters the top of the filter housing (stainless steel or plastic) where it is evenly distributed over the bags. The filtrate leaves the filter housing again at the bottom, while the dirt stays behind. The bags are stuck from the top, so that all the dirt stays in the bag and cleaning the house is not necessary. The bags are usually easy to replace by hand.
Sand filtration is used for the removal of suspended solids, as well as floating and settable particles. The waste water flows vertically through a bed of fine sand and / or gravel. Present particles are removed by adsorption or physical encapsulation. If the pressure drop across the filter becomes too large, it must be backwashed. Before rinsing, the dirt is released from the sand by starting to inject air from bottom to top. Filtered water then flows through the filter bed in countercurrent. The contaminated material is released and flows with the flushing water. The filtration process can resume. An important advantage of a sand filter is the simple installation with which in many cases a considerable return can be obtained.
Groundwater often contains dissolved and undissolved iron and manganese. These elements cause a brown deposit on the machine parts and come into contact with the water. As a result, installations are struggling with malfunctioning processes, pollution and a shortened service life. In addition, iron and manganese also give the water an unpleasant taste and odor. The best way to avoid all these problems is de-ironing and de-mangling. The process often goes through an aeration phase and one or more filtration phases. During the aeration phase, the water is aerated with dissolved iron (Fe2 +) to allow the iron to oxidize. The oxidation is usually carried out with compressed air. The oxidized iron (Fe3 +) is no longer dissolved and will be separated as iron flakes in the sand filter.
ACTIVE CARBON FILTER
Adsorption is a waste water treatment technique for removing a wide range of compounds from industrial waste water. Adsorption is most commonly used for the removal of low concentrations of non-degradable organic compounds in groundwater, drinking water preparation, process water or as tertiary purification after, for example, biological water purification. Adsorption occurs when molecules in a fluid attach to the surface of a solid. Adsorbents have a very high internal surface where adsorption can take place. Activated carbon is by far the most used as an adsorbent and is particularly suitable for the removal of non-polar compounds. This can be supplied in both fixed holders and mobile holders.