Activated carbon filters work through carbon beds. Component carbon bed activated carbon particles have many microholes and huge surface area, and have strong physical adsorption capacity. Water passes through the bed of carbon, the organic pollutant in water is adsorbed by activated carbon. In addition, the non-crystalline parts of activated carbon have some oxygen tube groups, and the organic pollutants in the water through the carbon bed are effectively adsorbed by activated carbon. Activated carbon filter is a more commonly used water treatment equipment, water treatment desalination system can effectively guarantee the pretreatment stage equipment service life and improve water quality, pollution prevention, especially after level to prevent reverse osmosis membrane, ion exchange resin and so on more than pollution free oxygen toxicity. The main factors influencing the effect of carbon filtration adsorption and service life are: type and concentration of pollutants, retention time of air filtration materials, temperature and humidity of air. The actual choice is to determine the form of the filter and the type of activated carbon according to the type, concentration and treatment of pollutants, such as air conditions. The activated carbon filter and downstream shall have a good dust filter, and its efficiency specification shall not be lower than F7. Upstream filters prevent dust from blocking activated carbon materials; The downstream filter stops the activated carbon itself.