Bioadsorber efficiency, design, and performance forecasting for alachlor removal

Area of Science:

• Environmental Engineering
• Biotechnology
• Water Treatment

Background:

• Drinking water purification faces challenges from chlorinated pesticide contamination.
• Granular activated carbon (GAC) is widely used, but its efficiency can be enhanced.
• Bioactive GAC, utilizing microbial biofilms, offers potential for improved contaminant removal.

Purpose of the Study:

• To develop and validate a mathematical model for bioactive GAC adsorbers.
• To investigate the dynamics of pesticide removal, using alachlor as an example.
• To compare the performance of bioactive and non-bioactive adsorbers and assess bioregeneration strategies.

Main Methods:

• Mathematical modeling incorporating film transfer, diffusion, and adsorption.
• Laboratory-scale experiments for parameter determination (isotherms, kinetics, biokinetics).
• Bioactive expanded-bed adsorber experiments and hybrid numerical methods for model solution.

Main Results:

• The model accurately predicted adsorber dynamics for both bioactive and non-bioactive systems.
• Sensitivity analyses identified key parameters for process efficiency enhancement.
• Scale-up simulations showed advantages of bioregeneration for extended adsorber lifespan.

Conclusions:

• Bioactive GAC adsorbers can be effectively modeled for pesticide removal.
• Fungal strains demonstrated higher efficiency in alachlor metabolism compared to bacterial strains.
• Bioregeneration offers a sustainable approach to enhance the longevity and performance of GAC adsorbers.