title: Remediation trials for hydrocarbon-contaminated sludge from a soil washing process: evaluation of bioremediation technologies.
abstract: The usual fate of highly contaminated fine products (silt-clay fractions) from soil washing plants is disposal in a dump or thermal destruction (organic contaminants), with consequent environmental impacts. Alternative treatments for these fractions with the aim of on-site reuse are needed. Therefore, the feasibility of two technologies, slurry bioremediation and landfarming, has been studied for the treatment of sludge samples with a total petroleum hydrocarbon (TPH) content of 2243 mg/kg collected from a soil washing plant. The treatability studies were performed at the laboratory and pilot-real scales. The bioslurry assays yielded a TPH reduction efficiency of 57% and 65% in 28 days at the laboratory and pilot scale, respectively. In the landfarming assays, a TPH reduction of 85% in six months was obtained at laboratory scale and 42% in three months for the bioremediation performed in the full-scale. The efficiency of these processes was evaluated by ecotoxicity assessments. The toxic effects in the initial sludge sample were very low for most measured parameters. After the remediation treatments, a decrease in toxic effects was observed in earthworm survival and in carbon mineralisation. The results showed the applicability of two well known bioremediation technologies on these residues, this being a novelty.
authors: CIEMAT, Avda. Complutense 40, 28040 Madrid, Spain. garcia.frutos@ciemat.es
authors: F J García
authors: FJ
authors: Frutos
authors: R
authors: R
authors: Pérez
authors: O
authors: O
authors: Escolano
authors: A
authors: A
authors: Rubio
authors: A
authors: A
authors: Gimeno
authors: M D
authors: MD
authors: Fernandez
authors: G
authors: G
authors: Carbonell
authors: C
authors: C
authors: Perucha
authors: J
authors: J
authors: Laguna
mesh_terms: D000818:Animals; D001673:Biodegradation, Environmental; D019149:Bioreactors; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006838:Hydrocarbons / Q000302:isolation & purification*; D009835:Oligochaeta / Q000378:metabolism; D010944:Plants / Q000378:metabolism; D012722:Sewage; D012989:Soil Pollutants / Q000302:isolation & purification*
chemical_list: D006838:Hydrocarbons; D012722:Sewage; D012989:Soil Pollutants