Application Of Rhamnolipid Biosurfactant In Heavy Oil Viscosity Reduction

As the development of the economy of our country, the requirement of energy also increased. The energy is the key factor supporting the healthy growth of our economy. However, the increasing demand of energy, poor supplying chain and energy security policies entitle heavy threaten to our energy safety. For the healthy growth of our economy, it is necessary for us to support our self and explore new resources. Though the total reserves of oil and gas are considerable, the common high production is coming to an end. Consequently people now are turning to find new resources of non-conventional oils (mainly thick oil) to make up the short in oil supply. The heavy oil production has bright future.In many oil gas fields of our country, heavy oil is widely distributed, which is mostly existed in shallow reservoirs. Because of the existence of colloid and aspHaltene, the viscosity of thick oil is mostly so high. Microorganisms and its metabolism outcomes can lower the dense oil viscosity, make dense oil draw out from the well bottom easilier and help dense oil transportation. Therefore, It is very important to take on a research on lowering dense oil viscosity with the microorganism.There are five sections in this dissertation:the first section is summarization of literature; and the second is identification of bacterium which produce biosurfactant, and fermentation study of bacterium; the third part is inside simulation of rhamnolipid biosurfactant in thick oil viscosityreduction; the forth part is researching the degrading mechanism by Biosurfactant; the fifth part is the conclusions.In this study, optimization is done from 5 lab preserved strain to find one with high production of biosurfactant. And further the physiological and biochemical test is done. Also, the viscosity reduction experiment is conducted for the fermentation broth of the biosurfactant on the Chenzhuang thick oil. And the quantitative analysis is done by GC-MS on the normal alkanes (including phytane, pristane), naphthalene, phenanthrene, fluorine, bisbenzothiazole, chrysene, polycyclic aromatic, steroid terpene biomarkers, and the conclusions are as follows: (1) Optimization is done on one strain 0-2-2 with high efficiency biosurfactant from key laboratory of marine chemistry theory and technology, ministry of education, Ocean University of China, and the physiological and biochemical test show the strain is pseudomonas aeruginosa.(2) The test on the strain biosurfactant shows it has good stability with temperature, salinity and pH. Also it has wide range of temperature, salinity and pH. The critical micelle concentration of the biosurfactant is 40 mg/L.(3) Emulsification is done by fermentation broth and Chenzhuang thick oil, and the results show the optimized input quantity is 40% and emulsifying time is 12 h, and at this point the viscosity reduction rate is 64.02%. It also shows there is little differences between the results of centrifugal liquid, biosurfactant and fermentation broth. From the point of economical application and simplification industry, it has practical significance for the application of bio-surfactant for the viscosity reduction of Chenzhuang thick oil(4) GC-MS results show the input of biosurfactant changes the component of the thick oil, resulting the degradation and deduction of n-alkanes and polycyclic aromatic.