In-vessel composting--bioremediation of aged coal tar soil: effect of temperature and soil/green waste amendment ratio.
The biodegradation of 16 United States Environmental Protection Agency (USEPA)-listed polycyclic aromatic hydrocarbons (PAHs) present in contaminated soil from a manufactured gas plant site was investigated using laboratory-scale in-vessel composting-bioremediation reactors over 8 weeks. The influence of temperature (T, 38, 55, and 70 degrees C) and soil/green waste ratio (S:GW, 0.6:1, 0.7:1, 0.8:1, and 0.9:1) was investigated. A comparative study using a temperature profile during in-vessel composting-bioremediation to meet current regulatory requirements was also investigated. Temperature and amendment ratio were found to be important operating parameters for PAH removal for in-vessel composting-bioremediation of aged coal tar-contaminated soil. After 8 weeks of continuous treatment, the highest removal of 16 USEPA PAHs was observed at T=38 degrees C and S:GW=0.8:1 (75.2%). Lower removal of 16 USEPA PAHs was observed for temperature profile treatment (60.8%). We recommend that when conventional composting processes using temperature profiles to meet regulatory requirements for pathogen control need to be used, these should start with a prolonged mesophilic stage (6 weeks in this investigation) followed by thermophilic, cooling, and maturation stages.
Antizar-Ladislao
Blanca
B
Imperial College London, Wye Campus, Wye, Ashford, Kent TN25 5AH, United Kingdom. b.antizar@imperial.ac.uk
Lopez-Real
Joe
J
Beck
Angus J
AJ
D001673:Biodegradation, Environmental; D003033:Coal Tar / Q000737:chemistry*; D011084:Polycyclic Aromatic Hydrocarbons / Q000378:metabolism*; D012037:Refuse Disposal; D013696:Temperature; D013997:Time Factors
D011084:Polycyclic Aromatic Hydrocarbons; D003033:Coal Tar