| Summary: | Aims: The main objectives of this study were evaluation of the efficiencies of bioventing (BV), soil vapor extraction (SVE) and transition regime between BV and SVE (air injection bioventing [AIBV]) for benzene and toluene removal from polluted sandy soils.
Materials and Methods: Laboratory-scale set-up consisted of three cylindrical units (with 29 cm in length with a 7.29 cm i.d.) was conducted to study the removal efficiency of three in-situ remediation technologies.
Results: The results showed that, after 48-h air injection with constant air flow rate of 250 mL/min, benzene (initial concentration of 1 mg/g of soil) removal efficiency in BV, SVE and AIBV reactors were almost 84, 98 and >99.5%, respectively. Also results indicated that, toluene with a similar concentration was successfully (>99.5%) reduced via AIBV technology, after 72-h continuous air injection.
Conclusion: Comparison of the BV, SVE and AIBV technologies indicated that all of those technologies are efficient for remediation of unsaturated zone, but after specific remediation time frames, only AIBV able to support guide line values and protect ground waters.
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