The Influence Of Waste Water Leakage On The Groundwater Environment During The Process Of Denitration Catalyst Production

In order to reduce the emission of nitrogen oxides caused by coal combustion,denitration catalyst has been widely deployed in coal-fired power generation equipment.However,in the catalyst modification and regeneration factory,the storage devices that hold the wastewater and sewage may leak,causing chemical components seep into the underground aquifer through the unsaturated zone,which poses a serious threat to the groundwater environment.This paper takes this as the research object,discusses the migration pattern and the influence range of the contaminant in the unsaturated-saturated zone system under the abnormal condition.The main achievements of this study include following four aspects.(1)Field investigation and tests of groundwater environment were carried out on the basis of the systematically research area data collation.The standard index analysis method was used to analyze the survey data.We found that all of the items conform to the Groundwater Quality Standard(GB/T14848-93)category III water quality standard but the total number of bacteria item exceeds.The dual loop seepage test method and the diving steady flow pumping test method were used to obtain the hydrogeological parameters required for the numerical simulation study.(2)The conceptual model and numerical model of vertical one-dimensional flow in unsaturated zone were established,and the production and management of wastewater were analyzed comprehensively.COD and ammonia nitrogen were selected as prediction factors,and Hydrus-1D software was used to simulate the migration of contaminants.The curves of the concentration of the two contaminants in the unsaturated zone with the time and depth of the soil were obtained.The results show that the concentration of contaminants increases gradually along the section depth in unsaturated zone with time.After 140 d,with the adsorption capacity of the soil layer is saturated and reaches the equilibrium state,the contaminants reache the groundwater surface.(3)Under abnormal conditions,if the contaminants are not effectively managed within140 d,the contaminants will begin to leak to the phreatic aquifer.At this time,the Visual-Modflow software is used to simulate the horizontal two-dimensional flow of contaminants in the submerged aquifer,the migration trend of COD and ammonia nitrogen is predicted,and the influence range of the contaminants in different prediction periods is obtained.The comprehensive analysis shows that the maximum migration distance of thecontaminants in the submerged aquifer is far less than the distance from any submersible well within the investigation area after 10 a of the leakage.Therefore,under normal conditions,the leakage of the research object will not directly affect the Quaternary diving in the study area.(4)Based on the conclusion of the numerical simulation study,according to the different duration of the leakage of the pollutants,the prevention measures and control schemes for groundwater pollution are formulated.