Dust Pollution Analysis Of The Tailings Pond And Its Monitoring Network Optimization

Tailings dust pollution is one of the major local pollution sources of the urban ecological environment, and the quality of atmospheric environment has important significance for the sustainable development of the national physical and mental health, which is of significance to do research on optimization design of characteristic factor and its monitoring network of tailings dust pollution disaster on management of tailings dust pollution disaster. This paper uses the basic theory of fluid mechanics, studies the valley type iron ore tailings, constructs the index system of tailings dust pollution disasters, analyses characteristic factor with which to characterize dust pollution hazards, establishes a numerical model of tailings dust pollution, finishes the optimization of dust pollution monitoring network, and visualization research. The primary contents of this thesis areas following:(1) This paper analysis the influence factors of the tailings dust pollution disaster step by step with a deductive method, establishes an index system of the influence factors of pollution hazards. It analysis of influencing factors layer by layer with "tailings dust pollution" as the major premise,"external factors of dust pollution" and "internal factors of dust pollution " as the minor premise. The results show that, the external factors of tailings dust pollution mainly include the local atmospheric and local geographical factors; the internal factors mainly include the tailings and tailings factors influencing factors, etc. According to the demand of the article, the analysis of the impact factors ends with3to6layers, and the underlying basic factor is more than90species.(2) The thesis analyses weight function to the factors index system of tailings dust pollution by FAHP. The results showed that the consolidated weights in the third layer index before the index system of weights among the four are:wind, air humidity, tailings operating parameters, physical and chemical properties of tailings. Because the two branches of index (tailings operating parameters, physical and chemical properties of tailings) has a lower index, we find the underlying factors are characterized by dry beach area source parameters, tailings particle size and moisture content of the tailings. So it is concluded what used to represent the five characteristics of the tailings dust pollution disaster factor are wind, humidity of the air, dry beach area source parameters, tailings particle size and moisture content of the tailings.(3) By using incompressible Navier Stokes equation, the standard k-psilon turbulence model, the gas-solid two phase flow model, the finite volume method,following engineering and technical indicators related to tailings and modeling assumptions, This paper establishes numerical model tailings dust pollution, and simulates dynamic process of dust pollution of the valley type iron ore tailings under the action of wind power when it is surrounded on three sides by mountains, one side faces the damming ventilation. The results show that the choice of DPM discrete phase model of the FLUENT software to achieve numerical simulation of tailings dust pollution has better adaptability.(4) Based on the physical model of dust pollution tailings, it take total suspended particles (TSP) as the monitoring project, Construct monitoring network of the tailings dust pollution, Due to the overwhelming number of monitoring sites, the heavy workload of monitoring data processing, we consider to optimize the design for the dust monitoring network. Based on numerical simulation, it achieve the optimal solution by using a monitoring network based on fuzzy clustering analysis equivalence relation, we obtained optimal monitoring network optimization design. The results showed that, it is the best optimization program to constitute type I tailings monitoring network by selecting7#,24#,23#monitoring point, it can constitute type Ⅱ tailings optimization monitoring network by selecting19#,42#,29#monitoring point, it can constitute type Ⅲtailings optimization monitoring network by selecting22#、8#、44#, monitoring point it can constitute type Ⅱ tailings optimization monitoring network by selecting21#、38#、35#monitoring point, it can constitute type Ⅱ tailings optimization monitoring network by selecting23#、46、26#monitoring point.(5) Based on the process of numerical simulation, taking the Nanshan Iron ore tailings as an example, this paper analyses the influence of the dry beach area source size and wind factor to the tailings dust pollution disaster, and make the visualization research. The results show that when the wind speed is small, tailings dust concentrated floating in the near-surface space below20m, concentration of mineral dust in the upper air space is very low. With the increasing of the wind, mineral dust concentrations continue to lower near the vents end, the mineral dust floating in space continued to migrate in the near-surface inside the mountain to low, mineral dust trajectories is in a state of disorder, and gradually throughout the entire atmospheric region. When the wind speed is sufficiently large, the space occurs to the cyclone in the central region which ranges from20cm to50cm, cyclone concentration increase with increasing of the wind speed. The library under the effect of the annual average wind speed3.3m/s, there are a lot of tailings dust floating in the near-surface space, it threatens the near-surface tailings workers, the people around it, and the survival of other organisms. In the central region (20m～70m) patron body floating in the rear have more tailings dust, overall mineral dust concentrations perpendicular to the vent substantially symmetrical.