Application of Biodegradable Surfactant Washing to Remediate Total Petroleum Hydrocarbons-Contaminated Sediments

摘要

Kaohsiung Port is the largest international port in Taiwan. Sediments in the port play the role as sink for many waterborne pollutants [e.g., total petroleum hydrocarbons (TPH)]. In this study, heavy-oil contaminated sediments were collected from the Kaohsiung Port with an averaged TPH concentration of 8,878 mg/kg. The objectives of this bench-scale study were to evaluate the feasibility and optimal operational conditions using surfactant washing to cleanup the TPH-contaminated dredged sediments. Two different non-ionic surfactants [Simple Green(tm) (SG), and Tween 80] [with concentrations of 0.5, 1, and 5% (v/v)] were evaluated in batch experiments for their feasibility on TPH removal. Results show that up to 97% of TPH could be removed after washing with 60 pore volumes (PVs) of SG (5%) solution, while the sediment TPH concentration dropped to 320 mg/kg, which met the remedial goal of 1,000 mg/kg for TPH. Using river water as the washing agent could wash off approximately 15% of TPH from contaminated sediments. Results indicate a water-surfactant-water treatment scheme can be developed for field application. Thus, the total cost of sediment remediation can be reduced. The three-stage water-surfactant-water treatment train scheme would be expected to provide a more efficient and cost-effective alternative to remediate fuel-oil contaminated sediments.