Household pure water machine is the best solution to solve People's Daily drinking water, people know that pure water machine mainly use a variety of core filter to filter raw water to get pure water; UDF(granular activated carbon filter) plays an important role. Activated carbon has a strong absorption can adsorption some adsorption gas, liquid in a variety of substances such as tap water residual chlorine components. Standard configuration of pure water machine activated carbon filter elements are put in the second channel after the first PP cotton filter out solid suspended matter in the tap water residual chlorine adsorption, and then after the adsorption of water to the RO membrane after penetration; If the activated carbon is of poor quality or saturated, it cannot effectively adsorb residual chlorine, and the residual chlorine will produce destructive oxidation on RO membrane and eventually cause the water quality problem of pure water mechanism.