Household water purifier is the general name of water treatment unit that interrupts and concentrates impurities such as organic matter, chlorine and heavy metals in tap water. At present, there are mainly water purifiers for drinking fountains, direct drinking water purifiers, RO (reverse osmosis) membrane purifiers and household central water supply systems. The special water purifier for drinking fountains refers to the small terminal water treatment equipment popular in the market at present, which is used in conjunction with drinking fountains. Direct drinking water purifier, also known as direct drinking machine, refers to a comprehensive water treatment equipment that directly connects or adds tap water, completes a series of water treatment work in the machine, and finally comes out to directly drink raw water; RO (reverse osmosis) membrane water purifier refers to water treatment equipment that uses semi-permeable membrane to deeply purify raw water after pressure is applied. Domestic centralized water supply system is a kind of domestic water control system, which completes the advanced treatment, purification and distribution of water and realizes the quality diversion of drinking water and domestic water.
The purification principle of household water purifier is to remove impurities, suspended solids, residual chlorine, heavy metals, compounds and other toxic and harmful substances from tap water by means of adsorption, filtration and membrane treatment, so as to achieve the purpose of purifying water. The commonly used purification materials for household water purifiers are as follows:
(1) Non-woven fabric and PP cotton: remove granular impurities and colloids, and reduce the turbidity of water.
(2) Activated carbon: The huge specific surface area generated by abundant pores can adsorb small molecular organics, residual chlorine, disinfection by-products of tap water, colors, smells, heavy metals and other toxic and harmful substances in water, thus improving the taste of water.
(3) Cationic resin: remove heavy metals and excess calcium and magnesium ions in water, soften water quality and improve taste.
(4) Microporous ceramics: the filtration precision pore size is greater than or equal to 0.5 microns, and the suspended particles such as impurities and colloids are removed to reduce turbidity.
(5) Gradient ceramics: the filtration accuracy is 0. 1.5 micron, which can remove bacteria, effectively remove macromolecular organic matter in water and reduce turbidity.
(6) Domestic ultrafiltration membrane: the filtration accuracy is 0. 1 micron, and particulate suspended solids such as organic matter, impurities, colloid, bacteria and some viruses are removed. The effluent is high-quality drinking water. The filtration resistance is large, and the outlet water can only be produced by tap water pressure or water pump.
(7) Ultrafiltration hydrophilic membrane: the filtration accuracy is 0. 1 micron, and particulate suspended solids such as organic matter, impurities, colloids, bacteria and some viruses are removed. The effluent is high-quality drinking water, and the filtration resistance is very small, so it can be discharged without pressure during filtration.
(8) NF (nanofiltration) membrane: The accuracy is 0.0 1~0.00 1 micron, which can remove organic matter, bacteria and viruses, selectively remove heavy metal ions and excess calcium and magnesium ions (soften water quality), and retain some minerals and trace elements necessary for human body. The effluent is high-grade and high-quality drinking water. The filtration resistance is great, and it can only be discharged by tap water pressure or water pump pressurization.
(9) RO (reverse osmosis) membrane: the precision is 0.0 1~0.00 1 micron, which can remove organic matter, bacteria, viruses, metal ions and acid ions, that is, all substances except water, and the effluent is pure water. The filtration resistance is very large, and the effluent must be pressurized by a high-pressure water pump.
(10) KDF: High-purity copper and zinc particles treated by electrochemical redox (electron transfer). It can remove up to 99% chlorine and water-soluble soluble metals such as lead, mercury, nickel and chromium, and has achieved remarkable results in controlling the breeding of bacteria, fungi, dirt and algae.
References:
The textbook "Common Purification Materials for Household Water Purifiers" published by People's Education Publishing House summarizes the principle of simple water purifiers.
1 layer: gravel sand, etc. To remove larger impurities.
The second layer: activated carbon, through its adsorption, can adsorb some colored or colorless substances, just like upstairs said.
The third layer: alum [aluminum hydroxide colloid], which has adsorption effect and removes fine impurities!
Take an empty plastic beverage bottle, cut off the bottom, plug the bottle with a single hole with a catheter, turn the bottle upside down, and add washed fluff cotton, gauze, activated carbon (charcoal), quartz sand, pebbles, etc. Layers are stacked from bottom to top to get a simple water purifier.
Description:
(1) pebbles and quartz sand should be clean, and pebbles and quartz sand play a filtering role.
② If there is no single-hole plug with catheter at home, you can punch several holes in the bottle cap instead of the single-hole plug with catheter.
Advantages: cheap, novel, as if learning to do experiments when I was a child.
Disadvantages: Although you can drink it in theory, you are not at ease.
Effective time: observe the color change of sand by yourself. The deeper you sink, the more dirt you accumulate.