Abstract:A large amount of sintering machine head ash and desulfurization wastewater was generated during iron and steel sintering process, which contains high salt and highly toxic heavy metal thallium. The disposal of the ash and wastewater has become one of the key issues restricting the sustainable development of iron and steel industry. A synergistic treatment approach for high salinity solid waste containing thallium and high salinity wastewater was proposed. The results show that the concentration of thallium in the solution after washing is less than 5 mg/L by using 1/4 concentration activated carbon desulfurization wastewater as the leaching agent, moreover, the dissolution of calcium and magnesium also decreased. The effects of various components in activated carbon desulfurization wastewater on the leaching behavior of thallium during the leaching process of sintering machine head ash were studied. The results indicate that the presence of SO32? and appropriate pH value show a significant inhibitory effect on dissolution of thallium.