Abstract:Existence speciation and distribution characteristics of arsenic and mercury in typical tin smelting dust were studied. The results show that heavy metal pollutants in dust discharged by tin smelting enterprises mainly include arsenic, mercury, cadmium and tin, among which arsenic dust is the main element in rotary kiln and tin dust is the main one in fuming furnace. Arsenic content of rotary kiln dust is as high as 48.00% and mercury content is 0.005%, arsenic content of electric furnace dust is only 1.15% and mercury content is 0.0064%. Dust in rotary kiln is in form of coarse particle with +10 μm accounting for 34.83%. Particle size of fuming furnace dust is smaller with -3 μm accounting for 65.18%. Smoke dust in electric furnace mainly distributes in the range of small particle size with -1 μm accounting for 41.72%. Arsenic speciation in tin smelting dust is mainly As(Ⅲ), and mercury content is low and mainly exist in form of elemental mercury and mercuric oxide.