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A laboratory study was conducted to investigate the performance of composting bioremediation of a sand material contaminated with diesel fuel and radio-labeled phenanthrene. The material was amended with either fresh feedstock material or finished compost and then incubated at either thermophilic or mesophilic temperatures for 126 d. In controls that were not amended with compost, no mineralization of 14 C phenanthrene was detected, whereas treatments that received compost amendments had significant phenanthrene mineralization, ranging from 25% to 42% of initial concentrations. The lowest extractable diesel range organic residual (1092 mg kg −1 total solids) was observed in the treatment receiving fresh compost amendment and incubated at thermophilic temperatures, whereas the highest residual (8507 mg kg −1 total solids) was observed in the control without any amendment. Whereas all the treatments that received amendment dramatically outperformed the control reactors, significant differences were observed among the treatment performances. This suggests that amendment type and operating temperature were important factors impacting bioremediation performance. Résumé :Une étude en laboratoire a été effectuée pour examiner le rendement de la biorestauration par compostage d'un matériel sableux contaminé par du carburant diesel et du phénanthrène radio-marqué. Le matériel a été modifié avec du substrat frais ou du compost fini, puis incubé à des températures thermophiles ou mésophiles pour 126 jours. Dans les groupes témoins non modifiés par du compost, aucune minéralisation du phénanthrène 14 C n'a été détectée, alors que les traitements recevant des amendements de compost ont présenté une minéralisation de phénanthrène importante, variant de 25 à 42 % des concentrations initiales. La plus faible concentration extractible de résidu organique diesel (1092 mg kg −1 ST) a été observée dans le traitement recevant un amendement de compost frais et incubé à des températures thermophiles, alors que la concentration résiduelle la plus élevée (8507 mg kg −1 ST) a été observée dans le groupe témoin sans aucun amendement. Alors que tous les traitements recevant un amendement ont très grandement surclassé les réacteurs témoins, il y avait des différences importantes entre les rendements de traitement. Cela suggère que le type d'amendement et la température de fonctionnement étaient des facteurs importants ayant un effet sur le rendement de la biorestauration.

Abstract-This work was conducted to determine the production of methane from different organic waste substrates. Laboratory-scale reactors (5.0 L) operated at 55°C was used. Three different types of organic wastes were used: residential food waste, chicken manure, and secondary sludge from wastewater treatment plant. After 90 days of thermophilic digestion, it was found that the methane content range from 57 to 97.05%. The highest production of methane was obtained with municipal wastewater sludge while the lowest production was obtained with food waste. It was also found that methane production was affected by the ratio of waste to water (w/v). Wastes dilution ratio of 1:2 showed comparatively higher methane content than the wastes dilution ratio of 1:1.