.Ifpressuredispersionofthewaterenteringandwateroutexceeds10Psi（0.7kg/cm2）orthewateroutSDI＞5,thefilterneedtobebackflushed. Commonly,thefiltershouldbebackflushedoncebeforeoperationeverydayandalsobebackflushedwithgasonceaweek.
3.3Theactivecarbonfilter.
Theactivecarbonismadeofwood,coal,fruitshell(stone)andothercarbonaceousmaterialthroughthemethodofchemicalactivationorphysicalactivation. Ithasagreatdealofmicro-holesandhugesurface,soithasverystrongphysicaladsorptioncapabilitytoadsorbtheorganicinfec