The principle of using activated carbon to filter water is to utilize the porous properties of activated carbon to remove one or more harmful substances from the water by adsorbing them on the solid surface. Activated carbon adsorption has a good effect on removing organic matter, colloids, microorganisms, residual chlorine, odors, etc. from water. At the same time, due to the certain reducing effect of activated carbon, it also has a good removal effect on oxidants in water.
The commonly used method for filtering water with activated carbon is the ozone activated carbon method, sometimes also known as biological activated carbon (BAC). Its organic matter removal mechanism is first activated carbon adsorption, which allows those adsorbable organic matter to be adsorbed on activated carbon. Then, under the action of temperature, nutrients, microorganisms, and carbon particles, biomass gradually forms in the filter, and an uneven layer of bacteria and microorganisms is formed on the surface of the filter material. At this time, activated carbon not only has the function of adsorbing organic matter, but also has the biological degradation effect of bacteria on organic matter. To remove biodegradable dissolved organic carbon, it is necessary to use appropriate filter media and grow a biofilm on the filter media. Activated carbon is an excellent biological carrier that removes large particles and impurities from water, activated carbon adsorption various harmful substances and impurities in water, and purifies water quality. When there is a certain concentration of biodegradable dissolved organic carbon in the raw water, it can react with strong oxidants to increase the concentration.
Therefore, activated carbon filters are often used in conjunction with ozone in water treatment. Ozone oxidizes organic matter in raw water into biodegradable organic matter, while also increasing dissolved oxygen in the water, both of which are beneficial for the growth and reproduction of bacteria and other microorganisms in activated carbon filters water.