Phytoremediation with an Air Injection System

Phytoremediation is a plant-based technique with potential for enhancing the remediation of land contaminated by various pollutants. The use of deep-rooted plants for phytoremediation of contaminated soils has attracted a great deal of interest as an innovative alternative to other methodologies. As an innovative technique, in this study, air injected phytoremediation technique was introduced to enhance the remediation efficiency or to apply to the former soil vapor extraction or bioventing sites.To select the plant species, plant-screening test was conducted by comparing growth rates that were affected by four levels of diesel addition. Alfalfa showed the strongest resistance against the contaminant and its growth rate was not inhibited by diesel additions as corns and barnyard grasses were. Effects of air injection, alfalfa treatment, and air injection with alfalfa treatments on the removal of hydrocarbon were investigated by column studies to simulate the field situation. Polyvinyl chloride (PVC) columns were packed with diesel-contaminated soils. Both the removal efficiency of diesel and the microbial activity were the highest in air-injected alfalfa-planted column soils. It was suggested that increased microorganisms activity stimulated by plant root exudates enhanced biodegradation of hydrocarbon compounds. Air injection has contributed to the promotion of the microbial activity. Air injected phytoremediation may be useful as a further approach to remediate diesel contaminated sites. KCI Citation Count: 0