Study On Degradation Characteristics Of Oil Refining Wastewater In Drainage System

Oil refining industry is the pillar industry of our country and the world.Emissions in refinery wastewater were big.Concentrations of pollutants are high.The pollution components are complex,including alkanes,halogenated hydrocarbons,aromatic hydrocarbons,polycyclic aromatic hydrocarbons,benzene.It is difficult to make the refinery wastewater standard discharging or reuseing.Large petrochemical enterprise wastewater pipeline is long and have a long operation time.A certain amount of activated sludge deposited in the pipe.During refinery waste water transporting in pipeline,long-term domesticated sludge has a certain degradation on easy-degradation organic matters in waste water.Research on degradationin of refinery wastewater in biochemical treatment system and long-distance transmission pipelines can provide technical support for oil refining wastewater treatment system optimization.This study is based on a large-scale petrochemical enterprises.The refinery wastewater processed by the "floating oil-gas-biochemical isolation",then deliveried by long distance pipeline,mixed with sewage wastewater,and discharged after biochemical treatment.The removal rate of COD in primary biochemical unit,the first drainage pipelines,the secondary drainage pipelines,the mixing pool,the third drainage pipes and the secondary biochemical unit were 40.1%,14.9%,19.3%,9.2%,74.3%respectively.The removal rate of benzene content were 29.6 ~ 56.7%,0 ~ 7.6%,11.9~ 18.2%,8.9 ~ 18.2% respectively.The removal efficiency of phenolics were 23.5 ~62.3%,0 ~ 16.4%,9.8 ~ 16.7%,0 ~ 27.1%,80.7 ~ 98.7% respectively.The removal effect of aniline were 9 ~ 84.8%,0 ~ 84.8%y,5.4 ~ 16.7%,9.6 ~ 36.4%,42.9 ~ 98.5%respectively.68 kinds of organic matters were checked out in refining wastewater.Electron microscope scanning and high throughput sequencing of the sludge found that sediment a main microorganisms are Proteobacteria,Bacteroidetes(Proteobacteria)(Bacteroidetes),acidobacteria(Acidobacteria);B are mainly for sediment microbial Proteobacteria(Proteobacteria),Firmicutes(Firmicutes),followed by Bacteroidetes(Bacteroidetes),Chloroflexi(Chloroflexi);mud samples C mainly microorganisms Proteobacteria(Proteobacteria),followed by Bacteroidetes (Bacteroidetes),acidobacteria(Acidobacteria).In the sludge,the(Proteobacteria),the Bacteroidetes(the),the acid bacteria door(Acidobacteria)mainly decompose the paraffin and benzene series in the oil refining wastewater.