Study On Treatment Of Low Sulfur Dioxide Emission From A Metal Smelter

Jinchang City is a non-ferrous metal production-oriented industrial city,which industrial pollutants emissions are extremely large.The problem of air pollution has a serious impact on the air quality of urban living environment.Jinchuan Group copper-nickel smelter that uses fire smelting process,emissions of smelting flue gas contain lots of sulfur dioxide,which is the city largest source of sulfur dioxide pollution,also lead to serious pollution of sulfur dioxide for many years.In recent years,the environmental air quality of Jinchang has taken a significant change with the series of air pollution measures taken,but the status of sulfur dioxide as the main pollutant has not changed.In this paper,the source and emission of low altitude sulfur dioxide in the smelting plant were investigated and studied,and the pollution sources of the environmental protection flue gas in four furnace areas were monitored.Then the emission characteristics of the flue gas were analyzed.Through the comparison of desulphurization process scheme,considering the local factors,magnesium oxide desulfurization process was selected to control SO₂ in flue gas.The effects of low-level unorganized emissions SO₂ on the contribution of the hour surface were studied by using the AERMOD model in the meteorological and terrain conditions of Jinchang.The influence of SO₂ emission on the regional atmospheric environmental quality was compared before and after the treatment.Afterward verified the feasibility of the measures,and put forward the optimization scheme of high altitude discharge.Through this study,it can provide a reference for the selection of suitable chimney height,also can provide scientific guidance for the reduction of sulfur dioxide emissions and the improvement of environmental air quality in Jinchang.The main research contents and conclusions are as follows.?1?The concentration of SO₂ in the flue gas is significantly exceeded,the minimum exceeding the standard is 3.5 times,the maximum exceeding the standard is 20.5 times,and the difference of the excess ratio is more than that of the flue gas in the smelting furnace.It's the main reason for the intermittency of SO₂ concentration in the surrounding air of the smelter.The environmental flue gas has the characteristics of big fluctuation of flue gas flow,large variation range of SO₂ concentration,low temperature and high oxygen content.?2?Magnesium oxide desulfurization system can be used to control SO₂ in flue gas,which can significantly reduce the environmental impact of SO₂ emissions on the surrounding atmospheric environment,effectively improve the regional ambient air quality.The environmental benefits are very significant.Through the adoption of measures to strengthen the sealing,sealing leakage and transformation of hoods and other measures to improve the efficiency of environmental protection flue gas to ensure the removal of SO₂ effect and reduce the air pollution on the surface.?3?The effect of unorganized emissions on the contribution of regional ground is extremely important,whose existence is the root cause of SO₂ surface hour concentration.With the increaseof unorganized emission,exceeded the number of times and exceeded the time has also increased.The influence of the organized emission is obviously decreasing.The markedly increasing rate of SO₂ floor concentration at each point of interest increased steadily with the increase of unstructured emission,and there was a clear linear positive correlation.The correlation was analyzed by using the power function for the unstructured emissions and the excess area,and the results were significant positive correlation.?4?The governance of the regional air quality has improved significantly,and point of ground concentration of the concern and regional have greatly reduced.The reduction of the height of chimney height after treatment reduces the treatment effect,which resulting in the slightest increase in the concentration of the floor,and aggravates the pollution of the concern.?5?It is suggested that the improvement of the chimney height after treatment will be raised to 260 m so as to further improving the treatment effect and reducing the air pollution.When the height of the chimney height is 80-120 m,the maximum ground hour concentration will still exceed the standard.After the governance,the discharge height should be more than 120 m,in order to ensure that the ground concentration contribution can value the standard.With the increase of the height of the chimney height,the hourly,daily and average annual concentration of the study area showed a significantly decreasing trend.When the discharge height is within 180 m,the concentration of SO₂ is reduced obviously.After the emission height is 260 m,increasing the per unit height of chimney is significantly reduced for reducing the surface concentration of SO₂.