Study On Emulsification Stability And Treatment Technology Of Oily Wastewater

High oil content and serious emulsification have been two basic characteristics for oily wastewater.Firstly,this study researched the factors affect the stability of the emulsion,and then used the flocculation-demulsification method to treat oily wastewater according to its characteristics,optimized the process conditions,and finally achieved the goal of reducing the oil content in the wastewater.The main research results are as follows:According to the results of SEM,XRD,FT-IR,and EDS,the main components of suspended solids are Si O₂,Ca O and Ca CO₃,which have the characteristics of uneven surface and small gap diameter.Due to the surface characteristics of suspended solids,the interaction between the polar components of crude oil and the solid components,the crude oil stably exists in the"oil-particle aggregate"and is difficult to separate from it.Asphaltene and resin are the main components that cause the emulsification of crude oil,and the higher the content of both,the better the emulsification effect.The emulsification performance and stabilization effect of asphaltene is better than that of resin,which plays a leading role in the emulsification of crude oil,while resin assists asphaltene to improve the emulsification effect.In the study of the effect of surfactants on emulsions,the smaller the particle size of the emulsion droplets,the higher the strength of the oil-water interface film,the slower the decomposition of the emulsion,and the better the stability.The stability effect of the emulsion prepared by nonionic surfactants is obviously better than that of cationic and anionic surfactants.In addition,the concentration of surfactants,emulsification temperature,time,and oil-water ratio will also affect the stability of the emulsion.The contrast ratio R shows that the oil-water ratio has a relatively high degree of influence.Oily wastewater is neutral,with high turbidity,high oil content,and high suspended solids content.Its oil content has the characteristics of decreasing with the increase of standing time,and the oil removal effect is best at 18 h.According to the results of medicament screening,polyacrylamide and demulsifier DQ-P13 have significantly better degreasing effects.The process conditions were further optimized:the oily wastewater was allowed to settle for 18 hours,200 mg/L polyacrylamide was added,and 2.00%DQ-P13 was used.After demulsification at 80℃for 3 hours,the oil content in the oily wastewater It is reduced to 15.77 mg/L,and the oil removal rate is as high as 99.94%.The treated wastewater not only meets the relevant discharge standards,but can also continue to be used for the cleaning of oily sludge,which has engineering application value.