紫外活化过硫酸盐技术用于污水厂二级出水深度处理

Advanced Treatment of Secondary Effluent from a Wastewater Treatment Plant by Ultraviolet Activated Persulfate

城镇污水处理厂二级出水可作为再生水水源,其中所含有机物一直是备受关注的重要指标。利用紫外活化过硫酸盐技术(UV/PS)处理二级出水中的溶解性有机物,对比了单独UV、单独PS、UV/PS以及UV/Ti O2等4种反应体系的降解效果,并考察了PS投加量对UV/PS工艺处理效果的影响,同时分析了UV/PS工艺处理前后二级出水中有机物荧光特性和相对分子质量的变化,最后采用电子顺磁共振波谱(EPR)技术对反应过程中产生的活性氧化物质进行了分析。研究结果表明:PS浓度为5 mmol/L时,UV/PS工艺对二级出水的处理效果最好,其色度、UV254、UV280及DOC去除率分别高达100%、89%、91%和96%;反应过程中二级出水中的荧光物质和大分子有机物均被有效降解;硫酸根自由基和羟基自由基的共同作用具有良好的氧化有机物的效果。

Secondary effluent from wastewater treatment plants(WWTPs)can be used as the source of reclaimed water,and organic substance has always been an important indicator of concern.Ultraviolet activated persulfate process(UV/PS)was utilized to degrade dissolved organic matters(DOC)in the secondary effluent from a wastewater treatment plant.The treatment efficiencies of UV,PS,UV/PS and UV/Ti O2 were compared.Besides,the effect of PS dosage on treatment performance of UV/PS was investigated.Moreover,fluorescence characteristics and relative molecular mass of the dissolved organic matter in the secondary effluent before and after UV/PS treatment were analyzed.Finally,the active oxidizing substances generated during the reaction were analyzed through EPR technology.UV/PS process exhibited the best performance on the degradation of secondary effluent when the PS concentration was 5 mmol/L,and the removal efficiencies of chromaticity,UV254,UV280 and DOC were as high as100%,89%,91%and 96%,respectively.Fluorescent substances and macromolecular organic substances in the secondary effluent were effectively degraded during the treatment process.The combination of sulfate radical and hydroxyl radical had a good performance of oxidizing organic substances.