空气-泡沫驱提高采收率技术的安全性分析

Safety a-nalysis of enhancing oil recovery by air-foam flooding

空气-泡沫驱提高采收率技术的安全性问题一直是学术界关注的焦点,它关系到这项技术的应用。从气体爆炸极限和氧气的消耗两个角度对该问题进行分析。在气体爆炸理论的基础上,推导出天然气与空气混合爆炸工程估算的方法,并对一种实际天然气进行估算,得出该天然气的爆炸上限为3.210%,下限为10.320%;随着天然气甲烷含量的增加,估算出来的爆炸界限与甲烷单组分的爆炸极限值相接近。通过低温氧化反应及其动力学机理分析得出,由干低温氧化及用,空气中的氧气与原油中的烃类物质发生反应而被消耗,生成二氧化碳和一氧化碳等“烟道气”,从而增加了安全可靠性。现场测试的结果也证明只要注意控制注入压力和注入量,监测油管内气体含量,该技术就具有安全性。

The safety of EOR by air-foam flooding has always been the focus that academic circles care for,and it is related to the application of this technology.The prob-lem was analyzed from the viewpoints of gas explosion limits and the oxygen consumption.The method of engi-neering estimation of mixed explosion of natural gas and air was derived through gas explosion theory.One kind of actual natural gas was estimated and its explo-sion upper and lower limit was 3. 21% and 10. 32% respectively.With the increase of methane concentra-tion in the natural gas,the estimated limits were close to the one of single methane component.By the analysis of low temperature oxidation reaction and its dynamics mechanism,the safety was increased since reaction be-tween oxygen and hydrocarbon consumed the oxygen and produced carbon dioxide,carbon monoxide and some other flue gases.The field testing results proves that this technology is safe if only injection pressure and rate are controlled and the gas content in tubing is monitored.