| abstract |
The invention discloses a treatment method for electroplating mixed wastewater. The electroplating mixed wastewater does not contain cyanide and phosphorus-containing reducing agent. Lime emulsion is used to adjust and maintain the pH of the wastewater to 10.5-12, and sodium hypochlorite is added to oxidize sodium cyanide. and hydroxyl-containing organic amines and other pollutants; adding ferrous chloride solution, ferrous ions and calcium ions co-precipitate carboxyl-containing organic acid complexing agents in wastewater, and ferrous ions reduce hexavalent chromium to trivalent chromium and generate Chromium hydroxide precipitated; the precipitate was removed by filtration. Adjust the pH of the wastewater to 4.5-5.5, use sodium dimethyl dithiocarbamate or sodium diethyl dithiocarbamate to precipitate heavy metal ions, and use activated carbon to adsorb the precipitate and heavy metal scavenger; filter to remove the precipitate; adjust the pH of the wastewater To 6-8, use the current biodegradation technology to destroy the aliphatic polyamine complexing agent and reduce COD. The method can effectively remove pollutants such as heavy metals in the electroplating mixed wastewater. |