Comparison to add compost and vermicompost for removal disesel contamination soils using aerobic and anerobic reactor

摘要

Background and aims: Polycyclic Aromatic Hydrocarbons (PAHs) are a class of potentially hazardous chemicals of environmental and health concerns. This compounds exhibit toxic, carcinogenic and mutagenic properties and are listed by the United States Environmental Protection Agency (USEPA) as priority pollutants. The aim of this study was the comparison of aerobic and anerobic biodegradation of disesel contamination soils using municipal soil was to and vermicompost. Methods: This experimental study was accomplished in pilot scale with application of a copmpost pile consisting 1000:120 ratio gram soils to gram of petroleum. This mixture was then mixed in a ratio of 1:2 with compost and vermicompost fertilizer separately (two parts soil and one part compost and/or vermicompost). In this research, phenantheren (phc), a three benzene ring compound, was selected as a PAHs representative. Phenanthrene concentration was measured using HPLC after extraction from contaminated soils by ultrasonic method. Results: The results showed that the effective degradation of phc occures during two first weeks, and then the removal rate was decreased gradually. The decomposition rate on phc in the aerobic compost and vermicompost reactors was 89.5±9.1 and 91.7±7.0, respectively. At the same time, 19.2±5.1 and 26.4±5.0 of phc was removed in the anaerobic compost and vermicompost reactors, respectively. According to the results, phc maximum removal rate of 91.7±7.0 was achived in the aerobic vermicompost reactor. Conclusion: This study can be concluded that, with application of bioremediation at the ambient temperature, the polycyclic aromatic hydrocarbons may be removed from oil contaminated soils.