Bioremediation of Coal Contaminated Soil under Sulfate-Reducing Condition
Titel:
Bioremediation of Coal Contaminated Soil under Sulfate-Reducing Condition
Auteur:
Kuwano, Y. Shimizu, Y.
Verschenen in:
Environmental technology
Paginering:
Jaargang 27 (2006) nr. 1 pagina's 95-102
Jaar:
2006-01-01
Inhoud:
The objective of this study was to investigate the biodegradation of coal-derived hydrocarbons, especially high molecular weight (HMW) components, under anaerobic conditions. For this purpose biodegradation experiments were performed, using specifically designed soil column bioreactors. For the experiment, coal-contaminated soil was prepared, which contains high molecular weight hydrocarbons at high concentration (approx. 55.5 mgC g-drysoil-1). The experiment was carried out in two different conditions: sulfate reducing (SR) condition (SO42-=10 mmol l-1 in the liquid medium) and control condition (SO42-<0.5 mmol l-1). Although no degradation was observed under the control condition, the resin fraction decreased to half (from 6,541 to 3,386 mgC g-soil-1) under SR condition, with the concomitant increase of two PAHs (phenanthrene and fluoranthene, 9 and 2.5 times, respectively). From these results, we could conclude that high molecular hydrocarbons were biodegradable and transformed to low molecular weight PAHs under the sulfate-reducing condition. Since these PAHs are known to be biologically degraded under aerobic condition, a serial combination of anaerobic (sulfate reducing) and then aerobic bioremediations could be effective and useful for the soil pollution by petroleum and/or coal derived hydrocarbons.