Construction Of Groundwater Solute Transport Prediction Model Based On MATLAB

At the same time that China's social economy and science and technology have made continuous progress,groundwater environmental issues have also begun to enter the public's perspective.As an important resource that human beings must rely on,the groundwater environment should be given sufficient attention.This is also a necessary condition for China's industrialization and agricultural development.Protecting groundwater resources is of vital importance to social stability and sustainable development strategies.In order to guide and standardize the underground environmental assessment work and prevent further deterioration of the groundwater environment,the Ministry of Environmental Protection of China promulgated the "Technical Guidelines for Environmental Impact Assessment-Groundwater Environment"(HJ 610-2011)eight years ago and continuously revised it.And perfection,a new edition of "Technical Guidelines for Environmental Impact Assessment-Groundwater Environment" was issued in 2016(HJ 610-2016).Aiming at the difficulty in verifying the prediction results during the implementation of the Guidelines and the need for a large amount of basic data and difficulty in model establishment in the second-level evaluation of numerical methods,this paper uses MATLAB as the development platform,and uses MATLAB's powerful graphic visualization and data processing functions.Based on the kinetics of pollutant migration in porous media,and the application of MATALB / GUI programming and design to realize the visual operation interface of the corresponding solute transport analytical model,the development of the system is based on six types of groundwater environment prediction models,which are: one-dimensional points The source instantaneously injects pollutants and continuously injects pollutants;the two-dimensional point source injects pollutants instantaneously and continuously;and the three-dimensional point source injects pollutants instantaneously and continuously.The system can first select two prediction schemes,and input parameters such as initial pollutant concentration,porosity,and dispersion coefficient in the input area,and then directly display the solute concentration changes in the study area and their calculation results.Taking a power plant as an example,based on a detailedintroduction to the regional environmental profile and the hydrogeology of the evaluation area,two types of accident conditions that may occur during the operation of the thermal power plant are analyzed:(1)the industrial wastewater treatment facility fails or the wastewater treatment pond is damaged;(2)Sewage leakage occurred in the domestic sewage treatment station and the impervious layer was damaged;and the characteristic pollution factors of each accident in the above two abnormal working conditions were determined.Then,the six pollutant migration scenarios under two abnormal working conditions were predicted.Among them,the prediction of the one-dimensional model ignored the hydrodynamic dispersion in the y and z directions,and the prediction of the two-dimensional model ignored the water in the z direction.The main reason for dynamic dispersion is to better show the comprehensive functions of the prediction system.It also provides some references for users of the prediction system in the future when they encounter one-dimensional and two-dimensional hydrodynamic dispersion problems.For prediction in the three-dimensional instantaneous mode,When the distance from the leak point of industrial wastewater is x = 5m,y = 3m,z = 5m,the peak COD concentration is about0.238 mg / L,which is 3mg / L below its standard specification value,which will not cause groundwater environment.Pollution: For the prediction in the three-dimensional continuous mode,when the location from the leak point of domestic sewage is x = 5m,y = 5m,z = 5m,the ammonia nitrogen concentration in the groundwater has not exceeded the standard,and it will not cause pollution to the groundwater environment.It can be known that the impact of the power plant on the groundwater environment under two abnormal working conditions is small,but the groundwater environmental pollution is irreversible.The groundwater resources are treated and protected,and the impact of pollution is reduced to the environmental level.By range,in order to promote a virtuous circle environment.The purpose of this system is to promote the implementation of the Guidelines,and at the same time to solve the problem of groundwater environmental impact assessment with a single hydrogeological condition in a fast and efficient way.The interface of the system is concise and generous,and it can be applied to the assessment of groundwater environmental impacts in various situations.The prediction results are vivid and intuitive,and have broad application prospects.