Airsparging
Airsparging
Faculty: Arvin Farid, Jim Browning, Elisa H. Barney Smith, Jon Bender, Ken A. Cornell
Students: Vahab Bolvardi, Atena Najafi, Mahsa Azad, Harlan Sangrey
Funding:
NSF Interdisciplinary Research (IDR) Program, CBET Award No. 0928703
EM fields can oscillate water dipole molecules, which can in turn stimulate mechanisms such as airflow, seepage, microbial activities, desorption, and volatilization. Several soil remediation technologies inject air into soil to enhance microbial activities for bioremediation and volatilization of organic contaminants for soil cleanup. The goal of this study is to electromagnetic ally stimulate mechanisms to enhance soil remediation. Recent research has also shown a strong potential to mitigate liquefaction by air sparging. Increasing air injection pressure will create air channels within high porosity zones for easy airflow. These channels are preferential paths for flow of the majority of the injected air. The size, spacing, and formation of these air channels cannot be controlled and air diffusion between these channels is extremely slow. Electric current has become popular to enhance remediation processes. However, electric current will find preferential paths of relatively higher electrical conductivity. In sandy or even highly conductive lossy clayey soils, relatively higher conductivity zones are the same high porosity zones, previously taken by air channels. EM waves can oscillate water dipole molecules to stimulate and enhance different transport mechanisms and increase hydraulic conductivity. EM waves propagate better in zones of low conductivity (low porosity zones (untouched by the previously mentioned methods). EM waves antennas can be designed to operate above ground, be directive to input more power in desired direction, and focus energy into desired locations with constructive radiation patterns. The heating effect due to oscillation by an EM field can also be controlled more easily than electric fields, using low voltage high frequency waves. Effect of variations in frequency and power level on enhancement of different transport mechanisms and microbial activities need to be studied. This study is essential for developing theoretical models necessary to simulate these interactions. In addition to enhancing airflow, the stimulation has the potential to enhance volatilization, microbial activities, and desorption of chemicals and heavy metals from soil-grains for cleanup.
Publications:
Arvin Farid, Atena Najafi, Jim J Browning, Elisa H. Barney Smith. “Effects of Air Injection Pressure on Airflow Pattern of Air Sparging,” Journal of Environmental Geotechnics, August 2019.
Arvin Farid, Atena Najafi, Jim Browning, Elisa H. Barney Smith, “Electromagnetic Waves’ Effect on Airflow during Air Sparging,” Elsevier Journal of Contaminant Hydrology, Nov 2018, pp. 49-58.
A Farid, A Najafi, J Browning, E Barney Smith, "Electromagnetic waves' effect on airflow during air sparging," Journal of contaminant hydrology, Vol 220, pp. 49-58, 2019
J Bender, A Farid, K Cornel, J Browning, E Barney Smith, "Electromagnetic Enhancement of Microbially Induced Calcite Precipitation," Geoenvironmental Practices and Sustainability, Springer, pp. 323-334, 2017
A Farid, M Azad, J Browning, E Barney Smith, "Electromagnetically Induced Transport for Soil/Groundwater Remediation," Journal of Geotechnical and Geoenvironmental Engineering 141 (3), 04014115, 2015
V Bolvardi, A Farid, A Najafi, J Browning, E Barney Smith, "Laboratory Study of Electromagnetically Induced Contaminant Removal, "IFCEE 2015, pp. 2657-2666, 2015
A Farid, A Najafi, M Azad, J Browning, E Barney Smith, "Electromagnetically Induced Transport in Water for Geoenvironmental Applications," Geo-Congress 2014: Geo-characterization and Modeling for Sustainability, 2014
A Najafi, V Bolvardi, A Farid, J Browning, E Barney Smith, "Laboratory Study of the Effect of Electromagnetic Waves on Airflow during Air Sparging," Geo-Congress 2014: Geo-characterization and Modeling for Sustainability, 2014
A Najafi, S Azad, A Farid, J Browning, E Barney Smith, "Study of mechanisms governing electromagnetic alteration of hydraulic conductivity of soils," Geo-Congress 2014: Geo-characterization and Modeling for Sustainability, 2014
A Farid, M Azad, J Browning, EH Barney Smith, "Electromagnetic Stimulation of Transport in Water for Geoenvironmental Applications," 2013
A Farid, S Azad, J Browning, EH Barney Smith, "Consequences of Electromagnetic Stimulation on Hydraulic Conductivity of Soils," 2013
M Azad, HDO Sangrey, A Farid, J Browning, E Barney Smith, "Electromagnetic stimulation of two-phase transport in water for geoenvironmental applications," Geotechnical Testing Journal 36 (1), pp. 97-106, 2013
M Azad, HDO Sangrey, A Farid, J Browning, E Barney Smith, "Interaction Between Electromagnetic Waves and Transport in Saturated Media," GeoCongress 2012: State of the Art and Practice in Geotechnical Engineering, 2012