Research On Removal Of Organic Pollutant In Drinking Water By Zeolite-Active Carbon

With the aggravation of organic pollution of the drinking water source and theimprovement of the water-quality standards, the conventional treatment craft of drinkingwater used in most of water plants in China can not remove the organic pollutanteffectively to satisfy people's demand in the water quality. Consequently, zeolite, as a late-model water treatment material, is combined with active carbon to dispose drinking waterat a deep level and removing the organic pollutant of drinking water further, so that tosolve the increasing contradiction between the aggravation of organic pollution of thedrinking water source and the striction of the water-quality standards.The study on the surface character and the activation of zeolite, and the static anddynamic adsorption of zeolite-active carbon are proceeded. The activation of zeolite adoptsthe means of dynamic activation. It chooses NaCl liquor as active agent that itsconcentration is 1mol/L. The activated zeolite presents homogeneous crystal structure. Itsmicropores increase obviously and distribute equably. The activated zeolite is suitable fordisposing drinking water at a deep level as adsorbent.It shows that the results of static adsorption experiment: The best matching of theadsorbent is 30% zeolite + 70% active carbon. The time of adsorption equilibrium ofzeolite-active carbon to CODMn is 5h. The absorption isothermal formula isq_e = 0.0757C_e^1.3457. After comparing the adsorptive character of the two kinds ofadsorbents, it educed: the adsorptive performance to COD_Mn of zeolite-active carbon issuperior to that of active carbon. The results of the main influencing factors experimentshow: the removal effect of COD_Mn and ammonia nitrogen by zeolite-active carbon isinfluenced by temperature inapparently. The removal rate of COD_Mn is influenced by pHvalue inapparently too. While the removal rate of ammonia nitrogen is influenced by pHvalue more remarkably than that of COD_Mn.Under the acid condition, the removal effect ofCOD_Mn and ammonia nitrogen by zeolite-active carbon is better. The optimal combinationconditions: pH value is 3.63, and the quantity of adsorbent is 2.5g/L. Here, the removalrates of COD_Mn and ammonia nitrogen are 19.80% and 37.25% respectively.It shows that the results of dynamic adsorption experiment: The removal effect ofturbidity, COD_Mn and ammonia nitrogen by zeolite-active carbon dynamic adsorption isbetter than that of static adsorption obviously. The removal capacity of zeolite-activecarbon to ammonia nitrogen is higher than to CODMn obviously. The optimal backfillheight is 450mm, the optimal filtering velocity is 6m/h. Here, the removal rates of turbidity,CODMn and ammonia nitrogen are 80%, 20.61% and 45.24% respectively.