气相饱和度对气体滑脱效应影响实验

Experimental study on the effect of gas saturation on slippage effect

开展砂岩CO2驱实验,研究滑脱效应与气相饱和度关系;利用束缚水测定高气相饱和度下的滑脱因子,引入强凝胶体系和高黏淀粉溶液测定低气相饱和度下的滑脱因子;通过在24.45%~100%气相饱和度条件下微观实验测定滑脱因子,分析滑脱因子随气相饱和度变化的原因.结果表明：随着气相饱和度的增加,气体滑脱效应先增加后减小,最后达到稳定.在气驱前期CO2不是连续相,滑脱效应影响较小;在气驱中期随着窜流通道数量的增加,滑脱效应不断增大;在气驱后期随着气窜通道的拓宽,滑脱效应逐渐减小.滑脱效应同时受气相饱和度和气相饱和度分布的影响.

In the process of CO2 flooding,the gas slippage effect was affected by gas saturation.However the relationship between slippage effect and gas saturation is disputed.For researching the relationship,the slippage effect was tested in CO2 flooding experiment which is under high gas saturation.However,the slippage effect under low gas saturation is hard to be tested.Therefore starch solution and plugging agent was used to build low gas saturation,and the slippage effect under low gas saturation was tested.Micro models were designed to find the reason caused the relationship between slippage effect and gas saturation.The result shows that slippage effect is little in the early stage of CO2 flooding,because the gas is not a continuous phase;slippage effect increased with the increasing number of gas flow channel in the middle stage of CO2flooding;and the slippage effect decreased with the increasing of channel radius.Therefore,the slippage effect is under the influence of both the gas saturation and the gas saturation distribution.