The invention belongs to the technical field of
wastewater treatment, and particularly relates to a method and
system for removing
heavy metals in
wastewater, and the
system comprises a collecting tank, a regulating tank, a Fenton-ultrasonic synergistic reaction tank, an addition and reduction
sedimentation tank, a
flocculation tank, a first
sedimentation tank, a three-cavity
nickel removal tank, a second
sedimentation tank, a multi-parameter monitoring tank, an A / O tank, a third sedimentation tank and a
clean water tank which are communicated in sequence. Discharging the adjusted
wastewater containing the
heavy metals into a Fenton-ultrasonic synergistic reaction tank to realize complex breaking of the complex-state
heavy metals; adjusting the wastewater subjected to complex breaking treatment to be neutral, so that heavy metals are converted into
hydroxide precipitates, and most of the heavy metals are removed at the stage; discharging the
treated water into a
flocculation tank, standing and precipitating, and enabling supernate to enter a
nickel removal tank; and an organic
sulfur catching agent is added into the
nickel removal tank to strengthen
chelation reaction, so that the
nickel content is less than 0.1 ppm. According to the
system, through four-stage cooperation of oxidation,
precipitation, dynamic capture and intelligent feedback, the complex nickel removal problem is solved, and the comprehensive heavy
metal removal rate is larger than or equal to 99.5%.