活性炭/石墨辅助污泥电渗脱水研究

Study on electro-osmotic dewatering of sludge assisted by activated carbon/graphite

以活性炭、石墨以及两者不同比例的混合物为添加剂,研究了不同配比添加剂对污泥电渗脱水性能以及滤液品质[总有机碳(TOC)含量、重金属浓度、有机物组成等]的影响机理。结果表明,活性炭与石墨都能够提升污泥的脱水性与导电性,其中相较于石墨,单独投加活性炭对泥饼的含水率降低最为明显,当投加量为5%污泥干重(DS)时,脱水效果最优,泥饼真实含水率由无投加时的46.0%(质量)降为42.2%(质量),污泥表观含水率降为41.0%(质量)。活性炭或石墨投加可显著降低阴极电渗滤液的TOC和重金属浓度,其中活性炭效果最优,石墨效果最弱。当活性炭投加量从0%DS增加至20%DS时,阴极滤液TOC含量从3740.4 mg/L降至2160.0 mg/L,而Cu、Mn、Cr、Ni、Cd、Zn、Hg和Pb等重金属元素浓度的降幅为57%~100%。研究成果将为含碳材料强化污泥电渗脱水提供基础数据支撑,并为污泥电渗脱水技术推广应用奠定理论基础。

Using activated carbon,graphite,and their mixtures in different proportions as additives,the mechanism of influence of different proportions of additives on sludge electro-osmotic dewatering performance and filtrate quality(total organic carbon(TOC)content,heavy metal concentration,organic composition,etc.)was studied.The results indicated that both graphite and activated carbon can increase the dewatering performance and conductivity of sludge.Compared with graphite,activated carbon showed the most obvious impact on lowering the moisture content of sludge cake.The optimal dewatering performance was achieved when the dose of carbon materials was set at 5%of dry sludge mass(DS),and the real moisture content of sludge cake was decreased from 46.0%(mass)to 42.2%(mass),while the apparent moisture content was decreased to 41.0%(mass).The addition of activated carbon or graphite can significantly reduce the TOC and heavy metal concentration of cathodic electrodialysis,the effect of activated carbon is the best,and the effect of graphite is the weakest.The TOC content of the cathodic filtrate decreased from 3740.4 mg/L to 2160.0 mg/L when the dose of activated carbon was increased from 0%DS to 20%DS,whereas the concentrations of heavy metals like Cu,Mn,Cr,Ni,Cd,Zn,Hg,and Pb decreased by 57%-100%.The research findings will provide fundamental data support for enhancing sludge electro-dewatering through carbon-containing materials and establish a theoretical foundation for the promotion and application of sludge electro-osmotic dewatering technology.