The invention relates to a method for treating heavy
metal wastewater by a superconductive HGMS-NZVI (high gradient
magnetic separation-nanoscale zero valent iron) coupled technique, belonging to the fields of resources and environments. The result proves that the optimal technological parameters of the superconductive HGMS-NZVI coupled technique are as follows: the addition amount of NZVI is 0.05-0.5 g / ml, the
magnetic gradient is 3-5T, the standing time is 1-15 minutes, and the distance i between the reaction tank
diameter d /
magnetic field generator and the reaction tank wall is less than 3. The 4878.62ml of
arsenic can be removed from every
liter of high-concentration
arsenic wastewater, and the removal ratio of
arsenic ions in the
wastewater is up to 99.56%. The operating method comprises the following steps: adding a right amount of NZVI into the heavy
metal wastewater, uniformly stirring, injecting the wastewater in the reaction tank in a superconductive high-gradient
magnetic field, and standing for some time. Before the treatment, no pretreatment is needed, and the pH value of the wastewater is not regulated. Under the technological conditions of the superconductive HGMS-NZVI coupled technique, the saturation adsorption quantity of NZVI is 16-18 mg / g (the arsenic
ion adsorption quantity of 1g of NZVI), and the technological parameters can be properly regulated according to the arsenic
ion concentration characteristic of wastewater.