| Water pollution was becoming intensified, while with the improvement of water-quality standards, the conventional treatment craft of drinking water used can not remove the venomousness and nocuousness in water and the improvement of human's living standard, more attention was increasingly paid to the sanitation and safety of drinking water. So adopting advanced drinking water purification to obtain high quality water was necessary.The study chose ceramsite, a late-model water treatment material, combined with active carbon to dispose drinking water at a deep level. The composite filter materials have an porous and highly dispersed solid material, large specific surface area and strong ability of adsorption and ion exchange. Molecular with higher stronger polarity and unsaturated were easily adsorbed by ceramsite, and it can also remove the ammonia-N in micro-polluted raw water. The O3/composite adsorption process fit ozone oxidation and composite adsorption together, the better mutually complementary of O3 and composite filter materials can remove the contamination effectively.The results of static adsorption experiment shows that: It chooses NaOH liquor as active agent that its concentration is 10%.And after drying the active carbon in the temperature of 110℃for 2h, it is torrefied under the condition of 260℃for 4h .Then the activated carbon presents homogeneous crystal structure. t is micropores increase obviously and distribute equably,and is suitable for disposing drinking water at a deep level as adsorbent. The best matching of the adsorbent is 70% active carbon + 30%ceramsite.The time of adsorption equilibrium of active carbon and composite filter materials to CODMn is 4h the same. The absorption isothermal formula is qe = 0.0407Ce0.6028 and qe = 0.1165Ce1.1984. After comparing the adsorptive character of the two kinds of adsorbents, it educed: the adsorptive performance to CODMn of active carbon- ceramsite composite filter materials is superior to that of active carbon only, and the quantity of adsorbent is 3g/L.Here,the removal rates of CODMn and NH3-N are 29.6%and 34% respectively.The results of the main influencing factors experiment shows that:the removal effect of CODMn and NH3-N by active carbon-ceramsite is influenced by temperature inapparently. The removal rate is influenced by pH value more remarkably than that of temperature. Under the acid condition, the removal effect of CODMn and NH3-N by active carbon-ceramsite is better. The optimal condition of pH value for CODMn remove is 2.5~5.5 and for NH3-N remove is 3.5~8.5,here,the removal rates of NH3-N is better than 30%. While, it has bad removal rates both for CODMn and NH3-N under the alkaline condition.The results of dynamic adsorption experiment shows that: The active carbon- ceramsite composite filter materials has good removal effect of rbidity, CODMn, UV254, NH3-N and NO2-1-N, and dynamic adsorption is better than that of static adsorption obviously. The optimal adsorption height and EBCT are 1000mm and 10min, corresponding the filtering velocity and flux are 10m/h and 0.8 L/min respectively. In the O3/composite adsorption process, ozone concentration and contacting time are the most important factor for the effect of ozone oxidation. Ozone concentration could result in a substantial removal of UV254 and NO2-1-N, while the concentration of CODMn and NH3-N will rise after ozone oxidation. But organic matters with larger molecules were broken into smaller ones, which improved the later adsorption ability, and the total removal rate achieved markedly. Therefore, the ozone concentration in this experiment is 2mg/L. Considering the O3 decomposed rapidly in water, the treatment effect are not always increase with longer contacting time. It is 8min in this experiment.Under the optimal condition for treating reservoir water, 1000mm of adsorption height 2mg/L of ozone dosage, 8 min of contacting time, 10min of EBCT, here, the removal rates of turbidity, CODMn, UV254, NH3-N and NO2-1-N are 92.2%, 87.7%, 86.3%, 88.6% and 92.3% respectively. |
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