| Medical waste incineration can produce dioxin-like persistent organic pollutants (POPs) easily. Activated carbon is usually used to remove dioxins from flue gas by injecting into a single bag filter. However, due to the large amount of fly ash in the flue gas, the effect of actived carbon adsorption dioxin is not significant. Therefore, there is not obvious effect of decreasing of dioxins in flue gas by injecting number of activated carbon, which also raises the consumption of carbon.The physical and chemical characteristics of medical wastes, including original physical composition, element composition, and chlorine content were analyzed. We found that chlorine-plastic increased the chlorine content of medical waste, and ash content can increase the amount of fly ash in the flue gas. Medical waste, with high content of chlorine and ash, may produce a larger dioxins concentration.The concentrations of dioxins in the gas, fly ash and slag of the medical waste incineration were detected. The dioxins concentration in the fly ash was significantly higher than the smoke and ash. The toxic dioxin isomers and congeners in flue gas, fly ash and slag have the similar fingerprint characteristics. Activated carbon adsorbent can reduce the concentration of dioxins in flue gas.In this paper, we use a Dual Bag Filter system to remove dioxin in a medical waste incineration plant. Experimental results show that Dual Bag Filter system can decrease consumption of actived carbon and reduce the concentration of dioxins in the gas to 0.06 ng/Nm3 (11%O2), which is far below Chinese national emission standards for hazardous wastes(0.5 ng/Nm3, 11%02). The concentration of PCBs and PCBz in the flue gas was reduced to 0.09 pg WHO-TEQ/Nm3 and 26.71 pg WHO-TEQ/Nm3. Dual Bag Filter system decreased the dioxins concentration in flue gas significantly, besides reduced the consumption of activated carbon. So it is a new effective method to control persistent organic pollutants in medical waste incineration.
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