Study On Treating Techniques Of Oily Sludge In Oilfield

A large amount of oily sludge was produced in the oil field,duing to severe emulsification,processing difficulties,without any treatment and discharge and into the production system.It is not only harmful to the environment,but also important factors of wastewater treatment and water quality deterioration.In this paper,the nature of petrochemical industry,the source and harm of oily sludge on environment were analized,and the disposal actualities in china and other countries were reviewed.In addition,the treatment technologies were introduced.In the light of DaQing oily sludge hard to treat,through adding demulsifiers and floulants to change condition the oily sludge,the oil, the water and solid phases of the oily sludge were successfully separated by the process of contaminatedsludgeconditioning-mechanical separa tion.The examination explored the solid-liquid ratio,the type and amount of demulsifiers,time and temperature,type and amount of theflocculants,condition of Centrifuga tion and so on.The results of experiment showed that the oil content of the sludge recovery rate of oil can over reach 90%.The treatment can recover crude-oil efficiently.Using X-ray diffraction and thermogravimetric analyzer and SEM to analyze the scaling samples.Test results show that the main ingredients of oily sludge is SiO₂ and mineral substance,besides,contained some aromatic hydrocarbon organics;Microstructure of oily sludge changed before and after of centrifugation,the texture becomes the dense from the loose and extrusion the oil and water of certain proportion.Oily sludge was treated in ultrasonic to remove the oil in the sludge.The effects ultrasonic power, ultrasonic frequency,ultrasonic treatment time,warm-up temperature,dosage and of demulsifiers on crude oil removal oily sludge have been researched.The results show that:ultrasonic frequency 40 kHz,power 500W,treatment time 5min,warm-up temperature of 50℃,0.005%of the demulsifier SP1ml,and removal rate of oil from Oily sludge was above 90% at this condition.The ultrasonic can improve the efficiency of crude oil removal.This experiment takes the sodium silicate,the polymerization aluminum chloride (PAC), the positive ion polyacrylamide (CPAM) as the raw materials,has prepared multi-skill inorganic high polymer flocculant PCSM.Inspecte the influence factors of the dosage,pH on sludge deoiling effect.Make use of the Mixed-type flocculant treat the oil field sludge, combining with the single factor experiment research of a silicon aluminium,a few addition CPAM on the effect of PCSM.Results show that Mixed-type flocculant has good deoiling effect compared with the single flocculant, and a few addition of CPAM can help improve the stability and flocculation effect of polyaluminum chloride containing activated silicic acid (PSAC).