The Morphological Study Of Heavy Metals In Storm Runoff On The Road In Xi’an

On sunny days urban dust in the air carry a certain amount of heavy metals to the ground, on rainy days the rain fall down to the ground to be runoff and contact with sendiment and carry a small amount of suspended solids into the rain. Dissovled heavy metals and the state of particles in heavy metal may exist a certain number of relations. This paper studies the geometrical shape of heavy metals in urban road stormwater and provide theoretical basis for the effective control of heavy metals in urban storm runoff.Take storm water runoff in Xi’an city as object, select the rain mouths of the first ring road and the second ring in east area, west area, south area and north area as the primary sampling points and select the residential and campus two sampling points for comparison. Using improved BCR method of runoff in the soil of different forms of heavy metals which is extracted. Use inductively coupled plasma mass spectrometry(ICP-MS) to measure content nine kinds of heavy metal include zinc, copper, iron, manganese, cadmium, chromium, arsenic, lead, mercury dissolved from storm water and extracted from suspend soil, nine kinds of heavy metal.Analysis of measurement results are as follows: 1.Evaluate water quality of Xi’an storm water runoff from the point of view of mass concentration of dissolved metals. 2. Make metals relevance analysis and factor and factor analysis of different kinds of dissolved heavy metals.3.Analyze the number of different forms of heavy metals in suspended solids and explore the relation of heavy metals dissolved and ones extracted from suspended solids. 4. Make statistical analysis of the different forms of heavy metals in suspended solid, explore the correlation between different forms of heavy metals and the relation between different forms of heavy metals and quality of suspended solids.Research results show that: 1. Zinc, copper, cadmium, chromium, arsenic of runoff are relatively close to the corresponding element content of natural rainfall. There is no clear pollution sources of zinc, copper, cadmium, chromium, arsenic on the ground. Concentration of manganese and iron is high in some sampling points. Manganese and iron content can be affected by the environment.2. The dissolved metals are under the influence of three factors, iron and manganese are affected by the releasing of mineral. Chromium, lead, mercury are affected by the road traffic. Cadmium and arsenic are affected by natural factors.3.The morphology of zinc in the suspended solids is randomly. Copper mainly exists in the form of oxidation state. Dissolved quality of manganese is higher than solid quality. There is a strong linear relationship between iron manganese.4. The quality of suspended solids and heavy metals in the form of the following has an obvious linear relationship: zinc of reduction state, oxidation state, residual state, copper of residual state and total particle state, dissolved manganese, cadmium of residual state, arsenic of oxidation and residual state.