Characteristics Of Oily Sludge And Research On Screening Fluidization Modulation Centrifugation Processes Effectiveness

The exploitation and processing of petroleum will produce large amounts of oily sludge that were from sedimentation tank,three-phase separator,oil spill accident and landing sludge generated in oil field operations projects.If the sludge was handled improperly,it can lead to secondary pollution.Environmental protection of oilfield started relatively late in our country.Currently it is still a lack of mature technology of oil sludge treatment and formed technology and an exemplary process.In recent years it is began to deal with the oily sludge in the true sense of terms and it gradually become central issue in environmental protection technology.In this study,the composition and properties of oily sludge was researched,then the parameters of screening fluidization modulation centrifugation process were optimized.The composition of oily sludge is complicated and the composition including organic,inorganic,plus chemicals and minerals.There are some differences in the content of oily sludge which is from different blocks of Daqing Oilfield as well as the particle size of mineral components.Generally oil content of the sludge is 15%to 50%,but the propertie of the oil which is from the oily sludge is substantially similar to the crude oil.Therefore,crude oil of oily sludge has a certain recovery value.The sludge samples were from different of seven plants of Daqing Oilfield.The paper aimed at the 13 samples to analyze the composition.The results show that heavy metals ions Cd,Hg,Pb and other ions are less than the target value and As and other nonmetal ions also do not exceed the required standards.At the same time contain both aliphatic hydrocarbons and aromatic hydrocarbons and other organic compounds like benzene and naphthalene and other harmful substances.The highest content of inorganic composition is SiO₂ which is about30%in the two phases of water-oil and the content of Al₂O₃ and Fe₂O₃ is also relatively high.The oil content of the sludge samples is uneven.The aging oil's is up to 48.92%,while oil content can be reduced to 0.01%after magnetic separation Process.The 10 samples of all is unqualified and most of the samples oil content are between 5%to 20%.Through inspecting of a Daqing Oily sludge treatment station which apply screening fluidization modulation centrifugation processes to treat oily sludge and found that the oil content of treated sludge decreased with decreasing of sludge and water ratio.But considering restricted dosage,the mixing ratio was adjusted to 1:4.Detergent dosage is 1000 mg/L,demulsifier dosage is 200mg/L and stir 2h in 70?.The results of site treatment show that oil content reduced from 20.41%to 1.71%on average applying screening fluidization modulation centrifugation Processes.So oil content of oily sludge can reached the Heilongjiang Province'local standards Comprehensive Utilization and Pollution Control Standards Of Oilfield Oily Sludge?DB23/T 1413-2010?which prescribed emission standards is less than 2%after the final treatment applying screening fluidization modulation centrifugation processes.