Supercritical fluid extraction–Oxidation technology to remediate PCB‐contaminated soils/sediments: An economic analysis

The remediation of PCB polluted soils/sediments, left to classical technologies such as incineration and bioremediation, is an overwhelming problem, given that vast amounts of spilled PCBs still exist in the environment after nearly three decades of PCB production ban. Other innovative, alternative cleanup technologies demonstrated that a better solution might exist. A two-step remediation process proposed for real-world PCB-contaminated soils/sediments, based on supercritical fluid extraction (SCFE) and supercritical water oxidation (SCWO), is economically analyzed in this paper. The base case of the process consists of three 2.5-m3 extractors operated in a 30-min cycle and a 29-m-long SCWO tubular reactor (0.385 m i.d.), which can treat yearly 36,000 m3 of contaminated materials. To assess the commercial potential and the economic feasibility of the proposed process, capital and operational costs are analyzed and the results show total costs of the process in the range of $142–174/m3 sediment. Comparison with other alternative technologies suggests that the SCFE/SCWO process is economically feasible and attractive for the remediation of real-world PCB highly contaminated soils/sediments. © 2004 American Institute of Chemical Engineers Environ Prog, 23: 222–231, 2004