Physical water treatment: filtration
One of the best-known methods, and a key component of virtually every water treatment plant, is the process of filtering the water. With a little technical understanding, you can even build a water filter yourself. Depending on the quality and pore size of the filters, sand, particulate matter, protozoa, algae, bacteria and, in extreme cases, even viruses can be removed from the water. The highest level of water treatment by means of filter technology is called „ultrafiltration“, a process that is used to produce ultrapure water by means of membrane technology, most commonly in the high-tech sector.
In addition to filters with different „mesh sizes“, which also include gravel or sand filters, activated carbon filters are especially prevalent in water treatment systems. On the one hand, activated carbon is relatively cheap, and on the other, its properties enable the extraction of unwanted chemicals from the water. Not only large water works, but also many household water treatment systems use multiple filters arranged in a row. Typically, these include a pre-filter, a coarse filter, a fine filter (e.g. containing kieselguhr) and an activated carbon filter. In addition, many mobile water treatment systems, such as those deployed in response to natural disasters, contain multi-stage filtration systems.
Unfortunately, filters are prone to becoming „caked“ with deposited particles, and also contaminated due to microbial growth and biofilm formation. Filters must therefore be regularly cleaned, maintained, disinfected and/or replaced to ensure optimum water treatment. Sanosil AG offers a range of outstanding water treatment products containing hydrogen peroxide and silver ions for these purposes.