Removal of creosote from soil by bioslurry reactors

Abstract

AbstractBiological slurry reactors were tested for removal of polynuclear aromatic hydrocarbons (PAHs) from creosote contaminated soil. Five bioslurry reactors, operated in parallel, kept the soil aerated, partially suspended and well mixed.The reactors were inoculated with indigenous microbes of the Genus Pseudomonas. Nutrients were added to maintain the optimum ratio of carbon, nitrogen, and phosphorus. Temperature within the reactors was approximately 25°C. The slurry consisted of approximately 30% contaminated soil.Results of pilot studies showed that approximately 90% of the total PAHs were removed in the first two weeks. Total PAH concentration in the soil was reduced from approximately 10,973 mg/kg to 1,097 mg/kg. Two and three ring PAHs, such as naphthalene, fluorene, and phenanthrene were approximately 96% removed in the first two weeks and higher ring compounds such as chrysene, benzo‐a‐pyrene, and benzo(b) fluoranthene were approximately 83% removed in the first two weeks.