Evaluation Stability Of Tahe Heavy Oil And Optimization Of Dilute Medium

Tahe oilfield is characterized by ultra deep,ultra heavy,high salt,high sulfide and high asphaltene.At present,the main developing method is blending light oil.With the development of heavy oil,light oil resources are increasingly shortage;and increasing the light component may damage the stability of crude oil colloid during the process,which may lead to the precipitation of asphaltene and influence production with high efficiency.This paper focuses on the quantity of light oil and stability of blending oil,clarifying the mechanism of crude oil instability from the characteristics of components,temperature,pressure and so on;Then we study stability of crude oil under different dilute conditions,and the suitable crude oil stability determination methods for Tahe oilfield,TCII(Tahe Colloid Instability Index)and TCS(Tahe Colloid Stability),were established,and it is verified by turbidimetric method that TCII is more accurate in determining the stability of Tahe crude oil,which provides a theoretical basis for the optimization of dilute oils;By evaluating the stability,fluidity and viscosity of dilute medium,the selection chart of diluted medium is established,which can help us confirm the appropriate dilution ratio range of dilution medium;and optimizing process parameters of 6 wells combining with the characteristics of mixed up oil,such as dilute ratio and depth,the economy and dilute blending quantity of projects are better than the actual one on site;then analyzing economic efficiency of projects to get the best project for production,the optimized project of TH12253 X is expected to increase 1839.2 yuan/ton compared with the actual one.This study solved the shortage of light oil in Tahe field and reduced the asphaltene precipitation problems in the process,providing a theoretical basis and technical guidance for exploitation and process optimization.