The Biological Electrochemical System Treats Copper Smelting Wastewater And Its Power Generation Performance

Copper smelting wastewater contains high concentration of heavy metals.If the wastewater is not treated directly,the wastewater will not only cause waste of resources,but also seriously pollute the environment.Traditional wastewater treatment methods include chemical method,physical chemistry method and electrochemical method.These methods have some disadvantages such as high energy consumption,they cause secondary pollution problems and they are hard to recycle metal.Bioelectrochemical system is a kind of device that uses the electron transfer ability of the anode microorganism to recover biomass energy.It mainly involves Microbial fuel cell?MFC?and Microbial electrolysis cell?MEC?.MFC can be used to power MEC,the MFC and MEC can constitute the MFC-MEC coupled system.MFCs were constructed.The effects of device parameters?volume,load,stirring,wire?,sludge?kind and concentration?,the anode substrate?kind and concentration?and electrode?anode material,electrode distance,superficial area?on the electricity generation capacity of MFC were studied.The results showed that reducing device volume,adding stirring device,reducing load,and increasing anode area could improve the production performance of MFC,when the anode substrate was glucose solution,the volume ratio of sludge to substrate was 1:2,the stirring speed was 500 r/min,the electrode material was carbon brush,the electrode distance was 4 cm,the anode area ratio of anode to cathode was 2:1,the maximum open circuit voltage was 0.626 V,the maximum power density was 211.6 mW/m².MFC can generate electricity and deal wastewater at the same time.The effects of device parameters,electrode and catholyte on the electricity generation capacity of MFC were studied.1)When the volume was 100 m L,the stirring speed was 500 r/min,the load was 10?,the removal rate of COD could reach 49.8%,the removal rate of Cu²⁺could reach 88.2%;2)When the electrode distance was 4cm,the electrode material was carbon paper,the anode area ratio of anode to cathode was 1:2,the removal rate of COD could reach 39.0%,the removal rate of Cu²⁺could reach 89.9%;3)The lower the initial concentration of copper ions,the higher the copper ion removal rate.Using MFC to treat heavy metal wastewater,the removal rate of COD could reach 41.6%,the removal rate of Cu²⁺could reach 88.5%,the cathode had red deposits after the reaction,the sediment was confirmed as single copper by XRD,the main surface topography were arborization and flake.The MFC-MEC coupled systems were constructed.The effects of the coupled system wastewater treatment were studied by changing the device volume,electrode material and initial concentration of heavy metal.1)The wastewater treatment effect of series connection was better than that of parallel connection,the removal rate of Cu²⁺was the highest,and the removal rate of Zn²⁺removal rate was the lowest;2)Reducing device volume was beneficial to improve the removal rate of heavy metal ions,the wastewater treatment effect was the best when using carbon brush as electrode material;3)Using MFC-MEC coupled system to treat copper smelting wastewater,in MEC,the removal rate of Cu²⁺was 89.6%,the removal rate of Zn²⁺was 99.2%,the removal rate of Cd²⁺was 89.7%,the removal rate of Co²⁺was 98.3%,metal ions were all effectively removed in MEC.The bioelectrochemical system can effectively remove heavy metals from copper smelting wastewater and bring new research direction to the treatment of copper smelting wastewater.