鄂尔多斯稠油组分特征与结蜡行为研究

Study on Components Characteristics and Wax Deposition Behavior for Heavy Oil in Ordos Basin

以鄂尔多斯油区边缘地带区块产出稠油作为研究对象,通过柱层色谱法和薄层色谱法对其进行组分分离,采用热重分析法分析了稠油热重行为,利用红外光谱对无法洗脱分离的稠油沉积物进行表征,对原油各组分通过紫外-可见光谱进行分析,并利用偏光显微分析法进一步考察分离出的组分对饱和烃析蜡行为的影响。实验结果表明：此稠油在失重过程中裂化反应和缩合反应交替进行,且油样整体失重速率较慢,沉积物中可能含有胶质和沥青质等强极性物质;原油组分中所含稠环芳香类化合物以环数3~4为主,且多以菲、蒽、萘等稠环芳烃存在,环数在4~7之间的稠环芳香类化合物相对较少;微观结构分析显示,稠油中相对分子质量较大的极性组分（胶质、沥青质）可以降低蜡晶之间的相互缔合作用,使蜡晶分散度和有序性增大,减少了蜡晶形成网络结构的趋势。

The produced heavy oil in edge blocks of Ordos basin was studied.Its components were separated by using column chromatography and thin layer chromatography.The thermogravimetric performance of the heavy oil was studied by using thermogravimetric analysis method.The deposit of heavy oil can ′ t be elution separation was characterized through Fourier transform infrared spectroscopy（FT-IR）.The components of the crude oil were analyzed by ultraviolet- visible spectroscopy（UV-Vis）.And the effect of isolative compositions on the wax precipitation of saturated hydrocarbon was investigated further by using optical microscope analysis method.Experiment results show that cracking reaction and condensation reaction alternately generate during the weight loss process of the heavy oil with slow mass loss rate.The deposits may contain resin and asphal-tene and other strong-polarity materials.The components of the crude oil mainly contain polycyclic aromatic compound with 3 to 4 rings,which is dominant as phenanthrene,anthracene,naphthalene and other polycyclic aromatic hydrocarbons.The polycyclic aromatic compounds with four to seven rings are relatively less.The mi-croscopic structure analysis shows that polar components with large molecular weight in the heavy oil,the resin and asphaltene,can weaken the interaction of wax crystal with each other.Dispersion degree and order of the wax crystal may be increased and tendency of gathering to network of it may be less.