Study On The Crude Oil Emulsion And Dendrimer-polyether Demulsifier Synthesis And Performance Evaluation

With the rapid development of industry, our demand for oil is increasing. So it has special significance to improve oil recovery ratio and make full use of limited oil resources. The main topic of this research is to study the influence of the common oil-displacing agent functional polymer, alkali, surfactant single monomer to the stability of the crude oil emulsion and the mutual synergies between the effect of the three oil production and the crude oil emulsion. For the characteristics of the EOR crude oil emulsion and the trend of demulsifiers, a series of Dendrimer-polyether demulsifiers with high branches structure were synthesized and the relationship between their structure and properties.Nuclear magnetic resonace (NMR) and infra-red spectrum(IR)measurements were used to analysis the configuration of the initiator and the demulsifier; the bottle test method was used to investigate the influence of the concentration and structure of the polymer,alkali and surfactants on the stability of the crude oil emulsion; the influence of the generation,the amount of the initiator and the proportion of m(EO)/m(PO) to the dewatering property of the demulsifier were discussed. The ability of the demulsifier to rupture the interfacial film was tested by single drop measurement, and cloud point and HLB were also determined by this method. Through this way, further discussion of the friendship between the structure and properties of the demulsifier was done.Conclusions were drew as follows: (1) Polymer, alkaline and surfactant played a significant role on the formation and the stability of crude oil emulsion; (2) The hydrophobic alkyl chain of the polymer played a pivotal role in inhibiting emulsion breaking, the higher content of hydrophobic monomers, the greater obstacles in space, so the stronger of the dehydration effect; (3) For the straight-chain surfactants, the stability of crude oil emulsion increased with the growth of carbon chain, and the Gemini surfactant was more stable than ordinary single-surfactant; (4) A serie of polyether demulsifiers were synthesized with polyamide-amine as initiator, and they all had better performance in demulsification; (5) With the reduction of the initiator, the demulsifiers had larger molecular weight, dehydration rate of the demulsifier increased. With the increase of the generation of the initiator, the demulsifiers had more branches and the dehydration rate increased. When the ratio of the ethylene oxide and propylene oxide was between 3:7 to 1:4, the demulsifiers had good dehydration rate, and the the demulsifier had the best dehydration effect when m (EO) / m (PO) value was1:3.