Kinetic modeling and simulation of the aldicarb pollutant removal from water and soil resources
Ehsan Ghorban Nezhad
1
(
Department of Chemical engineering, Quchan branch, Islamic Azad University, Quchan, Iran
)
Behrooz Mahmoodzadeh Vaziri
2
(
Department of Chemical engineering, Quchan branch, Islamic Azad University, Quchan, Iran
)
کلید واژه: Simulation, Kinetic modeling, Aldicarb, Aldicarb sulfoxide, Diffusion and transfer modeling,
چکیده مقاله :
Aldicarb is a relatively stable environmental pollutant that finds its way into natural resources via agricultural pesticides. In this study, modeling and simulation of aldicarb diffusion and decomposition process was carried out in water and soil resources. Different kinetic models like first-order, second-order, and the Power-law model with two orders of 0.5 and 1.5 were initially considered to predict aldicarb degradation in sterile and non-sterile soils. The aforementioned models in COMSOL MULTIPHYSICS software (version 4.2) were defined and executed in the reaction engineering module. The experimental data available in the literature were utilized to evaluate and validate the models presented. The predictions of second-order and Power-law (with order of 0.5) decomposition models had a further accordance regarding experimental data in sterile and non-sterile soils, respectively. In the following, simulations were run at various initial concentrations of contaminant using the best kinetic models to specify the effect of pollutant concentration on the removal process. Then, the diffusion trend and degradation of aldicarb were investigated in groundwater aquifers. For this purpose, a combination of reaction engineering model (based on 0.5-order Power-law model) and components mass transfer model in dilute environments was utilized in the structure of COMSOL MULTIPHYSICS. According to the results, it was found that only the top 25% of the aquifer layers are contaminated with aldicarb.
چکیده انگلیسی :
Aldicarb is a relatively stable environmental pollutant that finds its way into natural resources via agricultural pesticides. In this study, modeling and simulation of aldicarb diffusion and decomposition process was carried out in water and soil resources. Different kinetic models like first-order, second-order, and the Power-law model with two orders of 0.5 and 1.5 were initially considered to predict aldicarb degradation in sterile and non-sterile soils. The aforementioned models in COMSOL MULTIPHYSICS software (version 4.2) were defined and executed in the reaction engineering module. The experimental data available in the literature were utilized to evaluate and validate the models presented. The predictions of second-order and Power-law (with order of 0.5) decomposition models had a further accordance regarding experimental data in sterile and non-sterile soils, respectively. In the following, simulations were run at various initial concentrations of contaminant using the best kinetic models to specify the effect of pollutant concentration on the removal process. Then, the diffusion trend and degradation of aldicarb were investigated in groundwater aquifers. For this purpose, a combination of reaction engineering model (based on 0.5-order Power-law model) and components mass transfer model in dilute environments was utilized in the structure of COMSOL MULTIPHYSICS. According to the results, it was found that only the top 25% of the aquifer layers are contaminated with aldicarb.
