Study Of Ozone-Activated Carbon Removaling Odor Substances Of Drinking Water

Point source pollution, non-point source pollution and the wastewater of aquaculture in lack are important factors in causing eutrophication of Taihu.According to the quality study of a water plant in Suzhou, the major pollutants of East Taihu were TP, TN, organic pollutants, and the index of eutrophication was 54.4,being II water standards. The major odor substances are 2-MIB?GSM, the incidence being higher in June, July, August, September, which reaching the highest in July.The treatment of drinking water containing taste and odor materials by pre-ozone-conventional process and the pre-ozone-normal process-an advanced treatment process?O₃-GAC? were studied in this paper. By investigating original water of a waterworks in Jiangsu province, concluded in April, May odor substances in the raw water is lower, so dosing odor materials to study, and dosage was10ng/L⁵00ng/L. Studies showed that:?1?Removal efficiency of turbidity, organic matters, ammonia nitrogen by Pre-ozone-conventional process is good, while the treatment of low turbidity?<2NTU?, low organic matter?<2mg/L?, low ammonia concentration?<0.04mg/L? by O₃-GAC is better and quality of the water is stability.The turbidity of water stabled at around 0.2NTU, CODMn stabled at 1.20mg/L,ammonia concentrations were less than 0.02mg/L.?2? When the dosage of taste and odor substances in raw water were 10ng/L⁵0ng/L, after the pre-ozone-conventional process the contents of 2-MIB and GSM is lower than 10ng/L; when the dosage is80ng/L⁵00ng/L, the water quality does not meet the requirements. Increasing O₃-GAC treatment process, and in raw water taste and odor substances being<200ng/L, 2-MIB and GSM in the water of carbon filter column can not be found;taste and odor substances concentration of raw water was >200ng/L and <500ng/L,after the carbon filter column the contents of 2-MIB and GSM were lower than 1ng/L.?3? The removal rate of 2-MIB and GSM by pre-ozone-normal process-an advanced treatment process?O₃-GAC? is stability, and up about 99%, the effect of organic matter was not obvious. But the removal of 2-MIB and removal of CODMn by pre-ozone-conventional process was negative correlation, and R2= 0.40938.?4?Compared with the O₃-BAC of production process, it is concluded that biological phase had no obvious effect to the removal of odor and organic matter, but stabilized the process removing trubidity.The study of factors affecting granular activated carbon adsorping 2-MIBshowed:?1? Freundlich adsorption isotherm model is more suitable to describe the process of granular activated carbon adsorping and removing 2-MIB than the Langmuir adsorption isotherm model.?2? Due to the different substances in different water, which can occur competitive adsorption with 2-MIB, the parameters K and adsorption rate of GAC adsorping 2-MIB in distilled water is greater than the raw water and tap water; because tap water contains chlorine, resulting in the parameter K and adsorption rate of GAC in the raw water is greater than tap water, and the content of chlorine is greater, the affecting is more obvious.?3? Under alkaline conditions, the adsorption of 2-MIB by GAC is preferably; Mg2+, AL3+, Fe3+, and NO₃+ make the adsorption of 2-MIB by GAC on the decline, and affecting is obvious. While Na+, K+,Ca2+, CO₃2-, HCO₃-, SO42-is almost no effect to granular activated carbon adsorping and removing 2-MIB.