What harmful substances can household water filter cartridges filter?

With the improvement of quality of life and the enhancement of people's health awareness, more and more families begin to pay attention to the safety of drinking water. Especially in cities, although tap water basically meets the standards after purification in treatment plants, due to the old water pipe network, secondary pollution and other problems, the water that finally flows into the home is not always "safe water". Household water filters have become an important equipment for improving water quality and ensuring the health of household drinking water.

The purification capacity of the water filter mainly depends on the filter element structure and material inside it. At present, mainstream household water purifiers are usually equipped with multi-stage filter elements, each stage undertakes different purification tasks. The most common primary filter element is the PP cotton filter element. It is a fiber structure made of high-temperature melt-blown polypropylene material, which can effectively intercept large particles of impurities in the water, such as rust, silt, suspended matter, etc. Although these impurities are visible to the naked eye and seem to be less harmful, they are easily deposited in the water purification equipment, causing blockage and affecting the efficiency of subsequent filter elements. Long-term drinking may also cause chronic irritation to the gastrointestinal system.

After the initial filtration, the second stage is usually an activated carbon filter element, which is made of coconut shell or coal as raw materials and has a strong adsorption capacity. The main function of this type of filter is to improve the taste and smell of water, while removing residual chlorine, odor and some organic pollutants in the water. Chlorine is added to tap water during the disinfection process. Although it can kill bacteria, the residual chlorine not only has a pungent smell, but may also react with organic matter in the water to produce byproducts such as chloroform, which has potential carcinogenic risks. The microporous structure of activated carbon can adsorb these substances and improve the safety and comfort of drinking water.

For families with higher requirements for water quality, reverse osmosis (RO) filter elements are the key. The pore size of the RO membrane is very small, only 0.0001 microns, which is much smaller than the size of bacteria and viruses. Therefore, it can filter out almost all impurities in the water, including heavy metals (such as lead, mercury, arsenic, cadmium), bacteria, viruses, scale, nitrates, nitrites, etc. Reverse osmosis technology is widely used in seawater desalination and laboratory water, and represents one of the most advanced civilian water purification technologies. The water filtered by the RO water purifier is very pure, contains almost no impurities, and can be drunk directly. It should be noted that this type of equipment usually requires a booster pump, power supply and wastewater discharge system, and the installation and maintenance are relatively complicated.

Another more practical filter element is the UF (ultrafiltration membrane) filter element, which has a pore size of about 0.01 microns. Although it cannot filter soluble inorganic substances or heavy metals, it still has excellent interception capabilities for bacteria, colloids and some viruses. Compared with the RO system, the advantages of the UF filter element are that it does not require electricity, is easy to install, and does not produce wastewater. At the same time, it can retain beneficial minerals such as calcium and magnesium in the water, which is more in line with the concept of "clean but impure" drinking water that some users want. No matter which filter element is used, its filtering effect will decay over time. Once the filter element is saturated or blocked, not only will the filtering effect decrease, it may even become a breeding ground for bacteria. Therefore, regular replacement of the filter element is the key to ensuring the effectiveness of the water purifier.