Study On Oily Sludge Treatment Technology

Oily sludge is a different pollutant in oil field industry,which is difficult to deal with because of its complex compositions.In this paper,two types of oily sludge from Da Qing and Chang Qing were studied on the three-phase composition and oil content,which is a significant index.The oil content of Da Qing is between 5% and 28%,While the Chang Qing is 85% approximately.Four components,ash analysis and viscosity-temperature curve were investigated under laboratory conditions achieved quantitative understanding of the specific composition of oily sludge.Based on the analysis of the oily sludge,the oil washing rate and residual oil content by different quantity method were determined.Meanwhile,the unit operation of cleaning,demulsifying and flocculation were studied under laboratory conditions.The cleaning agent has direct effect on the cleaning effect of oily sludge.Considering the environment problems,it is proposed that the use of green environmental agents can greatly reduce the harm of oily cleaning agents to the environment.Three kinds of green environmental degradable cleaning agents,AEC-9Na,APG and MAPK were chosen and compared with common cleaning agents such as SDBS,SDS and sodium silicate.Firstly the surface of interfacial tension of the cleaning agents was determined.It was found that the interfacial tension of SDBS,AEC-9Na,a compound APG lotion,was less than 1mN/m at the range of determination.Based on the data,the effects of cleaning time,temperature,concentration and kinds of lotion on the washing rate were investigated,suggesting that the suitable cleaning time is 60 min;the suitable temperature was between 60 and 70?.With the raising of the temperature,the cleaning effect is obviously improved and the residual oil rate is further reduced.The concentration of different agents between 100 and 800 ppm were studied and the effect washing oil was obviously enhanced at higher concentrations.Secondly,the oil washing effects of common cleaning agents and three kinds of green cleaning agents in oil field were compared.The results show that the QX-2 of 800 ppm,stirred at 70? for 1.5h can reduce the oil content to 3.2%.Under the same conditions,APG-1214 and AEC-9Na can reduce the residual rate to less than 4%,which is close to the oil washing effect of SDBS.APG-1214 and AEC-9Na can be used as substitutes for the next generation oil field lotion.The environmental protection lotion can reduce the residual oil content to less than 4%,which can meet the standard of road construction and asphalt production.At the same time,it accumulates the experimental data for further advanced treatment to reduce the residual oil content.The demulsification and flocculation experiments of treated oily waste water were carried out,the results show that BH-33 demulsification is obvious with a short demulsification time,a smooth oil-water interface and a clarified water phase.