Method for recycling lead and zinc through refractory zinc oxide material step sulfidation roasting-flotation

The invention discloses a method for recycling lead and zinc through refractory zinc oxide material step sulfidation roasting-flotation. The method comprises the following steps of: 1) crushing and grinding; 2) drying; 3) performing step sulfidation roasting; 4) performing slow cooling and water-quenching; and 5) performing flotation. According to the method disclosed by the invention, dose of a vulcanizing agent is reduced by 5-10% while a relatively high lead and zinc sulphuration rate is obtained through step sulfuration roasting; sulfur dioxide generated in a reaction process is relatively low in concentration and is easily absorbed by alkali, and lead and zinc are recycled from roasting materials through a conventional sulfide ore flotation reagent, and therefore, the method is green, environmentally friendly and free of pollution.