approaching zero-discharge with cleaner production: case study of a sulfide mine flotation plant in china

in order to decrease the discharge from sulfide mine flotation plants, treatment and reuse approaches based on our previous wastewater monitoring experiments were explored in these plants. the flotation wastewater was collected from the case plant and was treated with coagulation sedimentation and activated carbon adsorption. then, the effluent was examined for reuse in the flotation process. furthermore, the effluent was also treated with sodium hypochlorite oxidation to avoid pollution in case effluent happened to be discharged accidently. the results showed that flotation wastewater pollutants could be eliminated effectively and reuse of the effluent did not cause adverse effects, during the six-year application of this procedure. in addition, flotation reagent consumption was greatly reduced, since the effluent containing mostly foaming agents could be reused. thus, this method proved to be environmentally friendly due to the decreased use of fresh water as well as being economically beneficial.