Biodegradation and absorption technology for hydrocarbon-polluted water treatment

Abstract

Wastewaters polluted with hydrocarbons are an environmental problem that has a significant impact on the natural ecosystem and on human health. Thus, the aim of this research was to develop a bioreactor sorbent technology for treating these polluted waters. A lab-scale plant composed of three 1-L bioreactors with different sorbent materials inside (meltblown polypropylene and granulated cork) was built. Wastewater to be treated was recirculated through each bioreactor for 7 days. Results showed that hydrocarbon retention rates in the three bioreactors ranged between 92.6% and 94.5% of total petroleum hydrocarbons (TPHs) and that after one simple recirculation cycle, no hydrocarbon fractions were detected by gas chromatography/Mass Spectrometry (GC/MS) in the effluent wastewater. In addition, after the wastewater treatment, the sorbent materials were extracted from the bioreactors and deposited in vessels to study the biodegradation of the retained hydrocarbons by the wastewater indigenous microbiota adhered to sorbents during the wastewater treatment. A TPH removal of 41.2% was detected after one month of Pad Sentec carrier treatment. Further, the shifts detected in the percentages of some hydrocarbon fractions suggested that biodegradation is at least partially involved in the hydrocarbon removal process. These results proved the efficiency of this technology for the treatment of these hydrocarbon-polluted-waters.