臭氧/高锰酸盐预氧化对生物过滤净水效能的影响

比较了臭氧(O3)和高锰酸盐复合药剂(PPC)对水源水预氧化的助凝效果及其对后续陶粒生物过滤净水效能的影响.结果表明,两种预氧化剂投加量均为2 mg/L时,PPC的助凝效果较为明显,浊度和溶解性有机碳(DOC)的去除率分别由未投加氧化剂时的85.7%和24.2%提高到88.3Z和35.2%;O3能够增加沉淀后水的可生化性,使特征紫外吸光度(SUVA)由0.97L/(m·mg)降至0.89 L/(m·mg).PPC预氧化有助于生物过滤对浊度的稳定去除,而O3预氧化则有助于生物过滤对DOC的去除.与O3预氧化相比,PPC预氧化有利于后续生物过滤运行初期对NH4 -N的去除,二者后续生物过滤在前3个月对NH4 -N的平均去除率分别为26.6%和73.1%,运行后期二者NH4 -N去除率接近.当进水NH4 -N大于2.0 mg/L时,DO是其去除的主要限制因素.

Enhanced water purification with preoxidation by ozone and potassium permanganate composite

Preoxidation using ozone(O3) and potassium permanganate composite(PPC) resulted in more effective water treatment by coagulation(including flocculation and sedimentation) and biofiltration.Peroxidation using 2 mg/L of PPC or O3 enhanced the coagulation effectiveness;the turbidity and DOC removal rates were 88.3% or 86.8% and 35.2% or 25.6%,respectively,relative to 85.7% and 24.2% without the preoxidation.The PPC preoxidation also resulted in better turbidity removal in the biofilter,while the O3 preoxidation made the organic constituents of its influent more biodegradable.During the first 3 months of the study,PPC was more effective in promoting NH 4-N oxidation in the biofilter with a removal rate of 73.1% relative to 26.6% achieved with O3 preoxidation;the two oxidants exhibited the same effect during the latter stage.Availability of dissolved oxygen controlled the degree of NH 4-N oxidation when the influent NH 4-N was >2.0 mg/L.