Abstract: Background, aim, and scope Soil pollution caused by heavy metal deposition in flue gas of incineratorfrom municipal solid waste incineration power generation project is the focus of environmental impact assessmentand environmental protection management. Materials and methods A municipal solid waste incineration projectwas selected as an example. Based on determining the incinerator emission intensity and meteorological data, theAERMOD was used to predict the settlement characteristics of Pb, Hg and Cd in incineration flue gas and theinfluence on the soil environmental quality in the area of the project. Results The cumulative concentrations ofPb, Hg, Cd were 16.35 mg ∙ kg−1, 0.2720 mg ∙ kg−1, 0.1310 mg ∙ kg−1 and the corresponding concentration standardrates were 4.7%, 27.2%, 21.8% respectively. The annual settlement of Pb, Hg, Cd in the downwind direction allincreased first and then decreased with the distance from the source and the corresponding peaks were 8.06 mg ∙ m−2(d = 400 m), 0.13 mg ∙ m−2 (d = 400 m), 0.04 mg ∙ m−2 (d = 300 — 500 m). The pollution coefficient which was relatedto wind direction, wind frequency, wind speed was used to measure the influence of wind on the diffusion ofpollutants, and the larger pollution coefficient meant the farther distance of corresponding equal settlement. Pollutioncoefficient was greater in the south than in the north, the west was greater than the east and the north-south wasgreater than the east-west. Discussion Although the cumulative concentrations of Pb, Hg, Cd all met the secondarystandard limits of Soil Environmental Quality Standard for Soils (GB 15618 — 1995), it should be paid attentionto in view of its harmfulness. The settlement of pollutants increased first and then decreased with distance from thesource. The distribution of pollutants had a good consistency with the pollution coefficient. The pollution diffusiondistance of the north was greater than that of the south, the east was greater than the west and the north-south wasgreater than the east-west. Conclusions Heavy metal in incineration flue gas from municipal solid waste incinerationpower generation project would enter the soil with atmospheric deposition. Therefore, predictions on the impact ofheavy metal deposition on the soil environment was necessary when carrying out environmental impact assessmentof such projects. In this research, the relevant departments should pay attention to the emission of pollutants fromwaste incineration especially Hg and Cd, although the sedimentation of heavy metal pollutants in incineration fluegas had not exceeded the standard. Recommendations and perspectives This research would provide reference forthe research and application work related to effects of gas with heavy metal pollutants on soil environment.
Keywords: municipal waste incineration; heavy metals; dry deposition; soil; atmospheric prediction