شبيه سازي و بهينه سازي روش هاي هوادهي پمپاژ-تصفيه در احياء محلي آبهاي زيرزميني

چكيده انگليسي :

Abstract Industrialization processes of societies always have destructive side effects on theenvironment Due to lack of necessary infrastructures for sustainable development thesedestructive side effects are larger in third world countries One of these destructive sideeffects is groundwater pollution due to industrial and domestic contaminants Herein inaddition to lack of infrastructures Iran needs more attention because of lack of waterresources Despite of surface water contaminant in groundwater usually stays stable anddecay process is very slow So it is necessary to clean aquifers using groundwaterremediation technologies One of the most conventional remediation technologies is Pump and Treat PAT PAT is based on pumping water from wells in the contaminated area andtreating it One of the recent technologies in groundwater remediation is Air Sparging AS which is used for Volatile Organic Compounds VOCs This technology is based on airinjection to the contaminated aquifer This injected air can clean up the aquifer since itdissolves VOCs and take them out of aquifer Although there are lots of suggestions forintegrating these two technologies during recent years but there is no integrated model forsimulation of these technologies in field scale yet So the aim of this study is to make anintegrated model for simulation and optimization of these two remediation technologies Insimulation field the main idea is using existing models and combining them with newones So MODFLOW2000 and MT3DMS are used for aquifer hydraulic and masstransport simulation in the integrated model By dividing simulation period into sub periods the ability of using Henry model for simulation of AS is made in the integratedmodel This means that in each sub period contaminant concentration in aquifer ismodified using AS simulation model Then by using these modified concentrations asinitial concentration values dissolved mass transport model runs for one sub period inorder to simulate PAT This process goes on until the end of simulation period Becausecombining AS and PAT is a new idea and due to lack of field and pilot results modelvalidation and sensitivity to length of sub periods is analyzed using simple physicalexamples which can make sense In addition the ability of integrated model in dualtechnology simulation is assessed within a case study In the subordinate part of this casestudy after assessment of TPH concentration values in Esmail Abad aquifer besideTehran refinery field of water head gradient and TPH concentration isolines were made Then an optimized PAT approach was suggested for aquifer remediation By consideringresults of first part of case study MTBE plume in Bagher Shahr at the west of Tehranrefinery was drawn Results showed that Bagher Shahr is completely located within theMTBE plume Using a five year dual technology remediation strategy suggestion contaminant mass removal inside the city area was assessed In the suggested strategy noremediation device installation inside the city was allowed In addition AS was used as acontaminant entrance limiting boundary After simulation of this strategy with theintegrated model it was found that contaminant mass inside the city would become half ofthe value of the no remediation case At the last part of this study an optimizer engine wasbuilt inside the model This optimizer engine uses genetic algorithm in order to optimizePAT and AS together This module of the integrated model can support ten AS wells andtwo PAT wells The objective function that this module considers is consist of cost for ASand PAT well installation Air injection water pumping and water treatment This moduleaccepts qualitative concentration constrains and quantitative pumping rate constrains Atthe end part of this study performance of optimizer module of integrated model wasassessed during an imaginary example In this example using both qualitative andquantitative constrains suggested AS ans PAT wells were optimized in terms of pumpingra

سرخك لاري، كاوه

شبيه سازي و بهينه سازي روش هاي هوادهي پمپاژ-تصفيه در احياء محلي آبهاي زيرزميني

مدل تلفيقي , صحت سنجي , روش گرادياني