磁性炭对好氧活性污泥降解2,4,6-三氯酚的强化作用

Enhancement effect of magnetic carbon on degradation of 2,4,6-trichlorophenol by aerobic activated sludge

【目的】酚类化合物属于原生质毒物,且难以生物降解,它的存在增加了生物处理的难度,成为废水处理的技术难点之一。为探究磁性炭对好氧活性污泥降解2,4,6-三氯酚的强化作用,分析了磁性炭对环境条件、系统运行稳定性及污染物去除率的影响。【方法】首先对新型磁性炭形态及物理特性进行分析,其次探究了磁性炭对好氧环境的影响,再次讨论了磁性炭对好氧污泥处理性能的影响,最后阐述了磁性炭对好氧污泥的影响。试验设置2个序批式活性污泥法(sequencing batch reactor activated sludge process,SBR)反应器:R1(SBR反应器1)为试验组,加入磁性炭材料;R2(SBR反应器2)为对照组,不加磁性炭材料。【结果】R1中pH值从8.20降为6.89,R2中pH值从7.90降为5.69,表明外加磁性炭能减缓活性污泥系统酸化;R1、R2组2,4,6-三氯酚的去除率分别约为90%和70%,化学需氧量(chemical oxygen demand,COD)去除率分别约为70%和54%,说明磁性炭不仅强化了2,4,6-三氯酚好氧降解效果,还提高了其彻底去除程度;生物量分别为5.54 g/L和3.75 g/L,污泥体积指数(sludge volume index,SVI)分别为32 mL/g和45 mL/g,说明磁性炭材料能增强活性污泥的生物量和沉降性能。另外,磁性炭材料能提高溶解氧(dissolved oxygen,DO)浓度,增强系统的导电性,提高活性污泥胞外多聚物(extracellular polymeric substances,EPS)含量,促进好氧污泥颗粒化,增强系统的抗冲击能力,使其更稳定地运行。【结论】本研究结果为磁性炭强化好氧污泥降解2,4,6-三氯酚提供了理论依据。

[Objective]Phenolic compounds belong to protoplasmic poisons and are difficult to biodegrade.Their existence increases the difficulty of biological treatment and becomes one of the technical difficulties of wastewater treatment.In order to explore the enhancement effect of magnetic carbon on the degradation of 2,4,6-trichlorophenol by aerobic activated sludge,analysis was conducted into the effects of magnetic carbon on the environmental conditions,the stability of system operation and the removal rate of pollutants.[Method]Firstly,the shape and physical characteristics of the new magnetic carbon were analyzed;secondly,the influence of magnetic carbon on the aerobic environment was explored;then,the influence of magnetic carbon on the treatment performance of aerobic sludge was discussed;finally,the influence of magnetic carbon on aerobic sludge was expounded.The experiment was set up with two sequencing batch reactor activated sludge process(SBR)reactors,i.e.,R1(SBR reactor 1)as the experimental group with magnetic carbon material added,and R2(SBR reactor 2)as the control group with no material added.[Result]Results show that pH in R1 decreases from 8.20 to 6.89,and pH in R2 decreases from 7.90 to 5.69,indicating that the addition of magnetic carbon can slow the acidification of activated sludge system;the removal rates of 2,4,6-trichlorophenol are about 90%and 70%,and the removal rates of chemical oxygen demand(COD)are about 70%and 54%in R1 and R2,respectively,indicating that magnetic carbon not only enhances the aerobic degradation effect of 2,4,6-trichlorophenol,but also improves its complete removal degree;the biomass is 5.54 g/L and 3.75 g/L,respectively,and the sludge volume index(SVI)is 32 mL/g and 45 mL/g,respectively,indicating that magnetic carbon materials can enhance the biomass and settling performance of activated sludge.In addition,magnetic carbon materials can increase the dissolved oxygen(DO)concentration,increase the electrical conductivity of the system,increase the extracellular polymeric substances(EPS)content of activated sludge,promote the aerobic sludge granulation,and enhance the impact resistance of the system,stabilizing its operation.[Conclusion]The results of this study provide a theoretical basis for the degradation of 2,4,6-trichlorophenol in aerobic sludge enhanced by magnetic carbon.