The treatment of black-odorous water using tower bipolar electro-flocculation including the removal of phosphorus,turbidity,sulfion,and oxygen enrichment

The large amount of municipal wastewater discharged into urban rivers sometimes exceeds the rivers’self-purification capacity leading to black-odorous polluted water.Electro-flocculation has emerged as a powerful remediation technology.Electro-flocculation in a bubble column tower with a bipolar electrode(BPE)was tested in an attempt to overcome the high resistance and weak gas-floatation observed with a monopolar electrode(MPE)in treating such water.The BPE reactor tested had a Ti/Ta2O_(5)-IrO_(2)anode and a graphite cathode with an iron or aluminum bipolar electrode suspended between them.It was tested for its ability to reduce turbidity,phosphate and sulphion and to increase the concentration of dissolved oxygen.The inclusion of the bipolar electrode was found to distinctly improved the system’s conductivity.The system’s electro-flocculation and electrical floatation removed turbidity,phosphate and sulphion completely,and the dissolved oxygen level improved from 0.29 to 6.28 mg/L.An aluminum bipolar electrode performed better than an iron one.Changes in the structure of the microbial community confirmed a significant improvement in water quality.

Alterations in microbial community during the remediation of a black-odorous stream by acclimated composite microorganisms

Microbial application is an efficient, economical, and ecofriendly method for remediating black-odorous rivers. In this study, the field treatment effect and microbial community changes were monitored during remediation by the acclimated complex microorganisms of a typical black-odorous stream. After the treatment, the total phosphorus and ammonia contents decreased by 74.0% and 76.3% and the concentrations of dissolved oxygen increased from 1.65 to 4.90 mg/L, indicating the effectiveness of the acclimated composite microorganisms. The proportion of Bacteroidetes decreased significantly by 48.1% and that of Firmicutes increased by 2.23% on average, and the microbial diversity index first increased and then tended to be uniform. Redundancy analysis demonstrated that the pH,dissolved oxygen, and oxidation-reduction potential together determined the composition of the microbial communities(p < 0.05). These findings showed that the acclimated composite microorganisms can effectively remediate the black odor.

Pollution control of urban black-odor water bodies

On the basis of on-the-spot investigation, the causes of urban black-odor water bodies and the problems existing in the treatment are analyzed, and the control techniques and management countermeasures for black-odor water bodies were put forward. The countermeasures include: treating from both the roots and the symptoms and combining multiple technologies; comprehensively managing and improve the monitoring systems; coordinating functions and implementing long-term management; opening information and innovating supervision platform; coordinating advance and promoting the construction of sponge city; diversified financing to form the market-oriented model of water pollution control.

Ecological Restoration Planning and Design of Campus River:a Case study of the Qiusuo Brook in China Three Gorges University

In view of the seriously-polluted water and broken eco-waterscapes in the Qiusuo Brook on campus of China Three Gorges University,this paper proposed the ecological restoration concept and mode of campus river according to field investigation and monitoring results,i.e. "reduce exogenous pollution—restore sediment microorganism—build intensified plant filter strip—build river water ecosystem and optimize landscapes—maintain ecological river course".In addition to introducing the design concept and principle of this mode,this paper specified the concrete projects such as sewage interception and water supplement,restoration of sediment microorganism,restoration of water plants,ecological restoration of embankment etc.,and also gave planar layouts and sketches of some projects,in order to provide references for the researches and practices of campus river ecological restoration in China Three Gorges University and other similar projects.