Bioremediation of PAH-Contaminated Soil via In-Vessel Composting

Abstract

This study is being conducted to investigate the biodegradation of polycyclic aromatic hydrocarbons (PAHs) present in contaminated soil using composting technology. Pyrene, a four-ring aromatic hydrocarbon, was chosen as a model PAH compound for the study. Preliminary investigations were carried out to assess the feasibility of soil composting by monitoring (a) carbon to nitrogen (C/N) ratio, (b) microbial consortia diversity, (c) coefficient of permeability and (d) moisture content. The soil was augmented with composted sludge, which was used as a bulking agent and nutrient supplement, in quantities ranging from 0-50% dry weight basis. Tests were conducted in both batch and continuous composters. In the batch composter, forty grams of soil/sludge mixtures in different proportions were spiked with 13.5 mg/kg (dry weight basis) of unlabeled pyrene. The batch composters were aerated and placed in a constant temperature water bath for a period of 21 days. Samples were soxhelet extracted and analyzed on the High Performance Liquid Chromatograph to determine the reduction in pyrene concentration. Analysis of these samples is in progress. In the continuous composter, the soil/sludge mixtures are spiked with both labeled and un-labclcd pyrene to obtain a total radioactivity of 13.5 µci. This process is being monitored for temperature, moisture content, volatile solids and microbial population. Mineralization of pyrene is assessed by quantifying 14CO2 produced.

James H. Johnson Jr.—Listen and find commonalities

“…Dr. Johnson's research on the technical aspects of metals and other hazardous waste materials (Diallo et al., 1998, 2008, Adenuga et al., 1992), academic training and policy perspective, and commitment to minority participation in environmental decisions (Johnson, 2011) made him uniquely qualified to be Chair of EPA's National Advisory Council for Environmental Policy and Technology (NACEPT, 2010). NACEPT is an independent committee that advises the agency on a broad range of environmental policy, technology, and management issues.…”

Solid Residuals Management at Centralized Vehicle Wash Facilities.

“…Specific literature citings which indicate the applicability of composting to residual and soils contaminated with hydrocarbons are widespread (Snell Environment Group 1982;Hogan et al 1989;Yusuf 1991;Adenuga et al 1992). Composting as a vehicle for biodegradation of oils containing waste solvents has been reported in Europe (Szabo et al 1988).…”