Optimizing electrokinetic remediation for pollutant removal and electroosmosis/dewatering using lateral anode...

Area of Science:

• Geotechnical Engineering
• Environmental Engineering
• Electrokinetic Remediation

Background:

• Soil electrokinetics (SEK) is a versatile technique applied in soil remediation, dewatering, and land restoration.
• Over 150 SEK process design modifications have been developed in the last 30 years to maximize performance.
• The integration of lateral electrodes/anodes in SEK systems has not been previously documented.

Purpose of the Study:

• To enhance the performance of the perforated cathode pipe soil electrokinetic remediation (SEKR) system (PCPSS).
• To investigate the effectiveness of installing lateral anodes (LA-PCPSS) for removing inorganic pollutants.
• To compare two approaches: different sources of applied voltages (DSAV) and the same source of applied voltage (SSAV).

Main Methods:

• Implementation of lateral anodes (LA-PCPSS) integrated with a perforated cathode pipe system.
• Application of two voltage supply strategies: DSAV and SSAV.
• Utilized the Taguchi approach (L9OA) to optimize applied voltages for the DSAV system.

Main Results:

• The DSAV-(LA-PCPSS) system optimized at 1 V cm⁻¹ showed the best response for indigenous Sr removal in kaolinite.
• Lateral anodes at position B with low applied voltage (0.5 V cm⁻¹) significantly improved electroosmosis (EO) rate/dewatering.
• Reverse ion migration was observed in the SSAV-(LA-PCPSS) system during real contaminated soil remediation.

Conclusions:

• The DSAV-(LA-PCPSS) design is effective for SEKR of inorganic pollutants and enhances dewatering.
• This innovative design offers minimal additional energy consumption compared to traditional PCPSS, presenting an economic advantage.
• The DSAV-(LA-PCPSS) system requires further optimization for intensified and highly efficient soil remediation processes.