The Research Of Environmental Hazard And Integrated Control Technology About Smelting Slag Yard

In recent thirty years, China's non-ferrous metal smelting industries have rapid development. It on one hand made great contribution on the our national economy, on the other hand, because of the poor production process, lots of solid wastes generated during this process also brought rather serious environmental problems -- heavy metal pollution..This paper was focus on WuLi metallurgical slag field in QiJiang Country, ChongQing, which was my research object. I have determined the main source of pollutant in slag field was the smelter slag of the former ChongQing smeltery based on the social impact survey. And it has seriously affected the surrounding environment and human'heath. To study the solid waste slag and surrounding environment in the field, I distributed the samples arrange from the internal and the surrounding slag field and surface soil. A total analysis of the samples shows: Cu, Ni, Zn, Pb have a high content; The contents of heavy metals in slag samples decline with the stockpiling depth, which shows the heavy metals have released into the environment during the stockpiling; All heavy metals except Cr exceed secondary standard in the 11 sample section; The average of the heavy metal's content has greatly exceed the background value and contrast value, which has tremendous influence and pollution on the surrounding areas. A correlation analysis shows there existed many kinds of composite heavy metals'pollutant with different levels, different combination surrounding the slag field.In this study, extraction toxicity identification tests and corrosivity identification tests were carried out for solid waste Identification . we could determine that the solid waste in deposit site belongs to the second type general industrial solid wastesThe release of heavy metal in solid waste to circumstance would influenced population health. The appearance of the influence to population health by heavy metal is as follows: acute toxicity effect,sub-acute toxicity effect,carcinogenicity,non-carcinogenicity etc. In this study, acute toxicity effect tests and sub-acute toxicity tests were carried out . According to the results of tests ,we could determine that median lethal concentration was above 2000mg/kg.bw . In accordance with the classification of acute toxicity for industrial waste,we could make sure that the solid waste in deposit site doesn't belong to acute toxicity hazardous waste. As the results of sub-acute toxicity tests showed ,there was no sub-acute toxicity of the solid waste in deposit site .In this study, the health risk assessment for deposit sites was carried out . its methods, procedures and indicators system were all discussed. non-carcinogenic and carcinogenic health risk on adult or child were studied, which through the channels of oral ingestion, skin exposure, and inhalation exposure caused by ingestion of contaminated substances. The evaluation of results showed that there was non-carcinogenic health risk within the bounds of 500m. The soil pollution must be treated .In accordance with the health risk assessment,soil risk assessment and ecological risk assessment,a comprehensive assessment system was set up. The degree of contamination for deposit site and its influenced district was divided to carryout comprehensive treatment. Physical remediation- phyto-remediation was presented to treat the pollution. Concrete step is:1,separation;2,recycle;3,landfill and regional ecology restoration. The implementing of pollution treatment could efficiently reduce environmental risk level.