油层矿物对蒸汽作用下稠油组成与粘度变化的影响

The Composition and Viscosity Changes of Heavy Oils after Aquathermal Cracking at the Presence of Reservoir Minerals

实验考察了辽河油田曙光采油厂的两种稠油在有和无油层岩心存在时水热裂解反应产物的差别。裂解反应温度 2 40℃ ,反应时间 2 4小时 ,油层岩心岩石矿物和粘土矿物组成已知。作为对照 ,还考察了相同条件下的热裂解反应产物。实验结果表明该油层矿物对低含硫稠油的水热裂解有催化作用。与单纯水热裂解结果相比 ,有油层矿物参与的水热裂解使两种稠油的饱和烃和芳香烃组分含量增加 ,胶质、沥青质组分含量减少 ,稠油平均相对分子质量略有下降 ,沥青质组分的平均相对分子质量有较大幅度下降 ,气体 (H2 、C1—C3 烷烃、CO2 及H2 S)生成量增加。两种稠油的粘度 (初始值 88.5和 12 4.3Pa·s)在水热裂解后分别下降 13.4%和 10 .6 % ,在油层矿物参与下水热裂解后则分别下降 2 5 .6 %和 2 3.4%。这一实验研究结果有助于研制高效的稠油水热裂解催化剂。

The effect of reservoir core minerals on aquathermal cracking (AC) of two heavy oils from Shuguang Oil Production Factory in Liaohe is investigated experimentally. AC is conducted at 240℃ for 24 hrs. The composition of rock and clay materials of the core is presented. The thermal cracking is also conducted for the purpose of comparison. The experimental results show that the reservoir core minerals exert catalytic effect on the AC of low sulfur heavy oils. In contrast to simple AC, AC with reservoir core minerals introduced leads to higher contents of saturated and aromatic hydrocarbon fractions and lower contents of resin and asphaltene fractions in the heavy oils, to slightly lower average molecular mass of heavy oils and much lower average molecular mass of their asphaltene fraction, and to much larger amount of the gases generated (H 2, alkanes C 1-C 3, CO 2, and H 2S). The viscosity of the two heavy oils (88.5 and 124.3 Pa·s) decreases by 13.4% and 10.6% after simple AC and by 25.6% and 23.4% after catalytic AC with core minerals, respectively. The results obtained help in preparation of highly effective catalysts for use in steam stimulation of reservoirs.