构建强化海油雪体系去除溢油的模拟研究

Simulation study on spill oil removal by strengthened marine oil snow system

溢油后生成的海油雪(Marine Oil Snow,MOS)会裹挟水中石油并最终沉降,而MOS中残油的释放会对海洋生态构成威胁。以固定石油降解菌(Petroleum Degrading Bacteria,PDB)的生物炭为强化剂,构建了强化海油雪(Strengthened-MOS,S-MOS)体系并研究了其对石油的去除机理。结果表明:与MOS相比,S-MOS絮体中的PDB分泌了更多的胞外聚合物(Extracellular Polymeric Substances,EPS),且紧密结合型EPS占比更高,导致生成的S-MOS絮体尺寸更大且更密实;对絮体中EPS主要组分的分析结果显示,S-MOS比MOS含有更多的蛋白质及多糖,表明强化后其疏水性增强且吸附位点增多,因而增强了对海水中石油的捕获能力;S-MOS比MOS体系脱氢酶活性高57.2%,对石油的去除率提高了44.3%。

Marine Oil Snow(MOS),which is generated after an oil spill accident,can trap oil in the seawater and eventually settle to the sea floor,and the release of residual oil from MOS can pose a threat to marine ecology.In this study,biochar which can immobilize Petroleum Degrading Bacteria(PDB)was used as a stimulation agent to construct a Strengthened-MOS(S-MOS)system,and the mechanisms of oil removal were explored.The results showed that the PDB in S-MOS group produced more Extracellular Polymeric Substances(EPS)and a higher proportion of Tightly-Bound EPS,resulting in larger-size and denser S-MOS flocs.The analysis of the main components of EPS in flocs showed that S-MOS had more proteins and polysaccharides than that in MOS,indicating that the addition of stimulation agent increased the hydrophobicity and the oil adsorption sites of flocs,and further increased the ability to capture oil in seawater.Dehydrogenase activity in S-MOS system was 57.2%higher than that in MOS,and the oil removal efficiency after strengthening was 44.3%higher than before.