机构地区: 五邑大学化学与环境工程系
出 处: 《环境污染与防治》 2007年第2期151-154,共4页
摘 要: 采用两个直流完全混合式反应器,研究了Ni(Ⅱ)、Cr(Ⅵ)对好氧活性污泥真实产率系数(YH)、COD去除率、MLSS和污泥呼吸作用的影响。结果表明,当Ni(Ⅱ)、Cr(Ⅵ)为3mg/L时,YH(MMLSS/MCOD)从无重金属的0.388分别升高到Ni(Ⅱ)的0.427和Cr(Ⅵ)的0.408;COD的去除率不受影响,MLSS增加了7.5%;污泥呼吸作用增强了5%。随着Ni(Ⅱ)、Cr(Ⅵ)浓度的进一步增加,YH、COD去除率、MLSS和呼吸作用都迅速下降。当Ni(Ⅱ)、Cr(Ⅵ)为15mg/L时,YH(MMLSS/MCOD)分别为0.289和0.218;而Ni(Ⅱ)、Cr(Ⅵ)为25mg/L时,对污泥呼吸的抑制作用分别达43%和60%。总体来看,Cr(Ⅵ)比Ni(Ⅱ)对系统的毒性更大。 Effects of Ni( Ⅱ ) and Cr(Ⅵ)concentrations on true bacterial yield (YH), COD removal, MLSS and sludge respiration (as specific oxygen utilization rate or SOUR) in two 5 L activated sludge aeration tanks were determined. Relative to the control system, the addition of 3 mg/L Ni( Ⅱ ) or Cr(Ⅵ)resulted in an increase of YH, from 0. 388 to 0. 427 and 0. 408, respectively, as well as increases in MLSS (7. 5%) and SOUR (5%), while it had no effect on COD removal. The YH, COD removal, MLSS and SOUR all declined at a higher concentration of Ni( Ⅱ ) or Cr(Ⅵ). When Ni( Ⅱ ) or Cr(Ⅵ)was 15 mg/L, YH was reduced to 0. 289 or 0. 218 respectively; 25 mg/L of Ni( Ⅱ ) or Cr( Ⅵ )caused 43 % or 60% reduction in SOUR. Present at the same concentration in the mixed liquor, Cr( Ⅵ )was more toxic than Ni( Ⅱ ).
领 域: [环境科学与工程]