组合式生物膜装置对受污染河水净化的中试试验

Pilot-Scale Test of Combined Biofilm Device for Purification of Polluted River Water

以某市受污染城市内河河水为原水,对研发的规模60 m3/d组合式生物膜装置进行了中试研究。组合式生物膜装置由进水过滤单元、生物处理单元、回流单元和出水单元组成,采用势能复氧、通过区域分隔和回流,在减少装置运行能耗的基础上强化污染物净化效果。结果表明在中试的试验进水水质下,当多级好氧池水力停留时间(M-HRT)分别为17.5、26.25和35 min时,随着M-HRT的增加,组合式生物膜装置对COD、NH+4-N的去除率也逐渐增加,对TN的去除率先增大后降低。与M-HRT为17.5 min相比,当M-HRT为26.25 min时其值分别增加了5.3%、9.7%和3.0%,而M-HRT为35 min时分别增加了6.7%、14.3%和1.7%。出现该现象一方面在于M-HRT增加,增大了多级好氧池循环流动的次数,促进了势能跌水复氧的效果,提高了好氧池的DO浓度,另一方面在于M-HRT增加,还增强水流的剪切作用,促进生物膜的生长,增加系统的生物量。

With the polluted river water of an urban city as the raw water,a scale of 60 m3/d combined biofilm device was researched in this paper.Combined biofilm device consists of water penetration filtration units,biological treatment unit,inverse flow unit and water units.On the basis of reducing energy consumption and enhancing the effect of pollution removal,potential energy recovering oxygen and pass regional segregation and inverse flow were used.The results show in the condition of pilot-scale research water quality,when the multi-level aerobic tank hydraulic retention time（M-HRT） is 17.5,26.25 and 35 min,respectively,with the increasing of M-HRT,the removal rates of COD,NH＋4-N increase,the removal rate of TN increases at first and then decreases.Compared with MHRT of 17.5 min,when M-HRT is 26.25 min,the removal rates of COD,NH＋4-N and TN increase by 5.3%,9.7%,3.0%,respectively; when M-HRT is 35 min,the removal rates of COD,NH＋4-N and TN increase by 6.7%,14.3%,1.7%,respectively.The reason of this phenomenon lies in the increasing of M-HRT,increases the number of cycles of the multi-level aerobic tank,promotes the effect of potential energy recovering oxygen,and improves of DO in aerobic tank; the increasing of M-HRT,increases shearing action,promotes the growth of biofilm and increases biomass.