Model of well clogging during in situ groundwater deironing

Summary

The study focused on the evolution of aquifer porosity during operation of in situ groundwater treatment systems at a water intake facility in the Russian Far East. The objective was to evaluate precipitate distribution and changes in aquifer hydraulic conductivity within the near-wellbore zone. Predictive simulations of precipitate accumulation were performed. The resulting additional drawdown, as well as reductions in permeability and porosity of the near-filter formation, were assessed. The precipitation zone develops directly adjacent to the well at the injected oxygen concentration of 12.5 mg/l. Simulations show that precipitate accumulation near the well caused an additional drawdown of approximately 5 m and reduced the specific capacity of the well. Coupled groundwater flow and geochemical models of well clogging were developed. The models account for variable permeability and porosity controlled by the volume of deposited iron oxides.

Key words

filter , iron , permeability , well , porosity , filtration of coefficient , injection , pumping , precipitate accumulation , oxidation kinetics , oxygen