Methods for enhancing phytoextraction of contaminants from porous media using electrokinetic phenomena

摘要

The present invention relates to a method of remediating soil, water, and other porous media contaminated with organic and/or inorganic contaminants using plants in conjunction with an electric field applied through the medium to control movement of the contaminants and enhance removal of the contaminants from the medium. Applying an electric field in soil induces electromigration (movement of ions in the pore fluid), as well as electroosmosis (movement of pore water) and electrophoresis (movement of charged particles in soil such as colloids). In the present invention these phenomena are beneficially utilized to control the transport of charged and/or non-charged contaminants in soil within the plant root zone (rhizosphere) and to bring contaminants into the root zone, perhaps from a contaminated zone located deeper in the soil than the root zone. The effectiveness of the phytoremediation is also enhanced by preventing the soil from becoming so strongly acidic or basic as to kill the plants. The present invention significantly extends the utility of phytoremediation to cleanup of soils with deeper contamination plumes than are typically accessible to the roots of plants.