Determination of the efficiency of combination therapies on the bioremediation of petroleum spill aquatic ecosystem

Abstract

Environmental degradation resulting from petroleum spills had become a major menace in most petroleum rich regions of the world. The remediation potential of individual green materials and their combinations were quantified in this study. Stimulated petroleum spill water was remediated with water lettuce, activated charcoal, rice husks and their combinations, within an experimental period of 40 days. The total petroleum hydrocarbons (TPH) value of the contaminated water and remediated contaminated water was determined in accordance with American Public Health Association’s (APHA) approved procedures. Findings of this study depicted that the amendments used were able to reduce the TPH concentration of the contaminated water; with activated charcoal tending to have higher remediation efficiency than rice husk. The results revealed that the TPH concentration of the contaminated water treated with only water lettuce, declined from 3897 to 1296 mg/L; while the TPH value of contaminated water treated with water lettuce and activated charcoal (C2 and C3), dropped from 3897 to 535 mg/L and 382.33 mg/L respectively, depending on the charcoal quantity employed. It was also observed that the TPH of the contaminated water treated with water lettuce and rice husk (C4 and C5), dropped from 3897 to 864 mg/L and 680 mg/L respectively, depending on the quantity of rice husks used for the bioremediation program. Additionally, the study’s findings revealed that the TPH of the contaminated water remediated with the combination of water lettuce, charcoal, rice husk and cassava starch (C6 and C7) declined from 3897 to 392 mg/L and 223 mg/L respectively. The study’s findings had depicted that agricultural waste materials can be harnessed to remediate petroleum spill sites, and the remediation efficiency can be optimized through combined remediation methods/materials.