The mainstream water purification equipment on the market is ultra-filtration machine and RO (reverse osmosis) machine.
RO machine is the core of the RO membrane, the pore size of the membrane is less than 1nm (1 nanometer; 1000nm = 1um; 1000um = 1mm). Water purification is accomplished through the principle of reverse osmosis.
The core of ultrafiltration machine is ultrafiltration membrane, the pore size of the membrane is 10nm~100nm. the principle is membrane separation technology.
And the size of the bacteria are larger than 100nm, all can effectively remove bacteria.
The filtration precision of ultrafiltration machine is not as high as RO machine, it does not need power supply, it is simple and convenient, and it can leave some minerals and trace elements while removing most of the harmful substances.
RO machine filtration precision is very high, strong purification ability, the need for external power supply, purified water for pure water, not recommended.
It is recommended to buy water purification equipment to ask the principle of purification, out of what water, can not drink directly.
Currently on the market there are many so-called functional water, such as "electrolytic water", "active water", "small molecule water", etc., these are not approved by the state.
The key to choosing is to figure out the problem of after-sales service, the water purifier is the need to regularly replace the cartridge, the cartridge used for a long time will lead to a decline in water quality. Now there are a lot of one-piece removable filter water purifier, this water purifier replacement filter is more convenient, the use of safer.
As for the brand, the market has a lot of brands, according to my understanding, "Shenzhou" direct water dispenser is quite good, is ultra-filtration. This is the aerospace group of companies produced by the brand quality can be guaranteed, this is the only one involved in the water purification industry state-owned enterprises, you can consider.
Personal opinion, for reference only.