Water purifiers are also called water purifiers. According to the structure of the filter element, they are divided into RO reverse osmosis water purifiers, ultrafiltration membrane water purifiers, energy water purifiers, etc. The standard RO reverse osmosis water purifier is equipped with 5 levels of filtration, namely: PP cotton, granular carbon, compressed carbon, RO reverse osmosis membrane, post-activated carbon (also called small T33) 5 levels; the ultrafiltration water purifier is based on ultra- The filter membrane is mainly used, and other filter elements such as activated carbon (excluding energy filters) are supplemented. Ultrafiltration water purifiers are divided into vertical and horizontal types according to the installation method. The vertical ultrafiltration water purifier is made of PP cotton, granular activated carbon , compressed activated carbon, external pressure ultrafiltration membrane, and T33; the horizontal ultrafiltration water purifier is composed of a stainless steel shell, an internal pressure ultrafiltration membrane, and KDF.
3M household water purifiers often classify activated carbon
1. Powdered activated carbon (PAC). Powdered activated carbon is actually finer granular activated carbon. Due to its small particles and large specific surface area, its adsorption effect is better than that of commonly used granular activated carbon.
2. Granular activated carbon (GAC). This is activated carbon commonly used in water purifiers. The smaller the particles, the better the adsorption capacity, but the greater the water resistance (inlet and outlet pressure difference), the easier it is to leak carbon. Therefore, the water purifier manufacturer should choose particles with suitable fineness. In large water treatment equipment, 10-24 mesh (diameter 2.0-0.8mm) is often used. For small 3M household water purifiers, it is recommended to use 16---32 mesh due to the short height of the carbon column, fast flow rate, and short contact time between water and activated carbon. Mesh (diameter 1.3-0.6mm).
3. Activated carbon fiber felt (ACF). According to different raw materials, there are two types: one is made from viscose fiber filament, processed into cloth, and subjected to carbonization, activation, and high temperature treatment; the other is made from polypropylene fiber-based fiber, which is processed into cloth. Felt is made by pre-oxidation, carbonization, activation and high temperature treatment. The average pore diameter is 17-26A for the former and 10-20A for the latter.
Activated carbon fiber is often made into felts with a thickness of 1-5mm. It has more micropores than granular activated carbon, a larger specific surface area (1000---1600m2/g), and a larger adsorption capacity (high 2-6 times), the adsorption speed is faster, and it has good regeneration performance, fast desorption speed and can be reused. The disadvantage is that it is more expensive and easy to breed bacteria.
4. Sintered activated carbon filter element (CTO), also known as carbon rod filter element and compressed activated carbon filter element. It is made of granular activated carbon added with a binder (such as PE resin), heated, sintered and extruded. The outer layer of the filter element is often wrapped with white polypropylene (PP) non-woven fabric. The sintered activated carbon filter element has both adsorption and filtration functions (average pore size 3-20um), but its filtration function is lower than the PP melt-blown filter element, and its adsorption function is lower than the granular activated carbon filter element.
Activated carbon can remove smell and taste, color, residual chlorine, colloids, organic matter, (synthetic detergents, pesticides, herbicides, synthetic dyes, trihalomethanes, haloacetic acids, endocrine disruptors such as Phthalates (PAES, etc.), heavy metals (such as mercury, silver, cadmium, chromium, lead, etc.), radioactive substances, etc. are the earliest and most widely used water purification materials used in water purifiers. Activated carbon is used not only in general activated carbon water purifiers, but also in household reverse osmosis purified water machines, as well as most ultrafiltration, ceramic, KDF, UV and other water purifiers.