火驱过程中稠油组分变化特征研究

针对火驱过程中稠油组分变化复杂的问题,基于CMG-WinProp模块,研究火驱过程中不同区带间的稠油组分变化特征。研究结果表明:燃烧带主要发生高温氧化反应,重质组分裂解为轻质组分;结焦带轻质组分聚合生焦转变为重质组分;油墙区主要富集燃烧反应后的轻质油。相图变化表现为随着火驱燃烧反应的进行,油藏温度逐渐升高,气液两相区面积逐渐增大,随轻质组分含量的增多相图临界点向左上方移动。研究结果对进一步认识稠油热采过程中的组分变化规律具有十分重要的意义。

Study on the Characteristics of Changes in Heavy Oil Components during In-Situ Combustion

In view of the complicated changes in heavy oil components during in-situ combustion, the characteristics of changes in heavy oil components between different zones in the in-situ combustion were studied based on CMG-WinProp module. The results of the study showed that the heavy components were cracked into light components by high-temperature oxidation reaction in the combustion zone; the light components were polymerized and converted into heavy components in the coking zone; the light oil after combustion reaction was mainly accumulated in the oil bank zone. The change of the phase diagram showed that with the progress of in-situ combustion, the reservoir temperature was gradually increased, the gas-liquid area was gradually widened, and the critical point of phase diagram moved to the upper left with the increase of light component content. The study results are of great significance for further understanding the laws of component changes in the thermal recovery of heavy oil.