TRANSPORT MODEL FOR ADSORPTION-DESORPTION OF ARSENIC ON IRON HYDROXIDE UNDER REDOX CONDITION

Arsenic contamination of groundwater has been rising as a critical issue to be solved. In this study, one-dimensional transport model for arsenic behavior with microbiological redox mechanism was developed. This model defined five reductive-bacterial groups and two oxidative-bacterial groups to model reductive sequence and oxidizing process. Microbial growth was assumed to follow Monod type kinetics. The numerical simulation model includes the chemical species in the bio-, mobile- and matrix phases. This model can describe the mass transport, bacteria mediated bio-chemical reducing processes, iron precipitation and Fe-As adsorption and desorption process. The simulation results can reproduce the results of soil column experiment, and validity of the model was confirmed.