微生物降解作用对稠油理化性质的影响

微生物采油技术(MEOR)的主要机理之一就是利用微生物降解原油中的胶质、沥青质等重质组分,降低原油粘度和凝固点,以达到改善原油物化性质的目的。利用从原油及含油污水中分离、选育出能有效降解稠油中重组分的菌种对青海、胜利、辽河、大港等油田的稠油进行了微生物降解实验,分析了细菌降解对原油饱和烃、芳烃以及胶质、沥青质各组分在原油中相对含量和内部组成的影响。结果表明,细菌作用引起原油性质发生明显变化,原油中胶质、沥青质含量降低9%以上,其组成和结构也发生了一定的变化,原油饱和烃轻重组分比值变大,粘度和凝固点分别降低15%和20%左右,大大改善了原油的物化性质。

MICROBIAL DEGRADATION INFLUENCES ON HEAVE OIL CHARACTERS

Degradation of oil is a most important part of the MEOR. This procedure can reduce the oil’s viscidity and freezing point and improve the oil’s fluxion in-situ. This paper shows the encouraging results of the microbial degradation on the heave oils gathered from several big oil fields in China. The results show that the bacteria can efficiently improve the property of the oils. The gum & asphalt content of the oils are lowered at above 9% and their structure is also changed a bit. The∑nC21-/∑ nC22+of the oils are enhanced through the microbial treatments and the shapes of oils in solution are changed greatly. The oils’ viscidity and freezing point are reduced about 15% and 20% respectively.