基于不同形式MFC的PRB对AMD处理效果影响
Effects of treatment efficiency of AMD through the PRB based on different structure of MFC
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摘要: 基于SRB生物阴极MFC的可渗透反应墙(SRB-PRB)原位处理酸性矿井水,MFC结构与MFC在SRB-PRB布局设计是影响预调节C/S,p H,M2+浓度效果的主要因素。实验构造了2种MFC结构(圆筒型、平板MFC)及在PRB中3种布局方式(点阵、顺流、横向渗流),用于相同体积活性填料的可渗透反应墙中,研究不同结构MFC对AMD的预处理效果。AMD水质为p H=3,ρ(SO2-4)=3 000 mg/L,Fe2+,Cu2+,Zn2+质量浓度均为30 mg/L,调节HRT为3,2.5,1.5 d。结果表明,MFC对AMD预处理调节效果与污泥碳源可利用性、MFC结构及在PRB中的布置方式有关,影响程度:碳源>MFC结构>布置方式。圆筒型MFC结构优于平板型,功率密度是平板型的2倍。3种布局方式圆筒点阵式结构PRB出水p H值在7左右,Fe2+,Cu2+,Zn2+去除率分别为96.2%100%,99.6%100%,95.3%99.3%,且均高于高于平板型;SO2-4去除速率平均高于平板式7 g/(m3·h)左右。圆筒型MFC点阵布局方式表现出性能稳定、设计灵活的特点。Abstract: The permeable reactive barrier based on sulfate-reducing bacteria biocathodes MFC ( SRB-PRB) was used in the in-situ treatment of acid mine water,and MFC structure and its layout design on SRB-PRB,pH value,ratio of C / S and heavy metal ion concentration are its main influences for pre-condition capacity. Two MFC structure ( cylin- drical,flat) and three different layouts ( lattice,downstream,lateral flow) in SRB-PRB were conducted for the same volume reactive medias in the PRB for the investigation of AMD pre-condition efficiency under the different MFC structure. The effluent concentration of Fe2+ ,Cu2+ and Zn2+ were 30 mg / L under the AMD conditions:pH = 3 and ρ(SO24- )= 3 000 mg / L. Experimental results show that the effects of MFC on precondition is associated with the avail- ability of sludge carbon source,the MFC structure and the PRB layout,the influence degree are as follows:carbon source>MFC structure>layout. Cylindrical MFC has a better performance than flat MFC,the maximum power densities is twice of flat MFC. The pH values are higher than the flat type,and is kept at about 7. 0 stably. The percent removal of Fe2+ ,Cu2+ and Zn2+ are 96. 2% -100% ,99. 6% -100% ,95. 3% -99. 3% respectively. The average removal of SO24- of cylindrical MFC is 7 g / (m3·h) higher than flat type. Lattice layout in SRB-PRB presents a characterizes of stable performance and flexible design.