基于高干度泡沫实验的非均质咸水层CO_(2)封存能力分析  

Experimental study on CO_(2) storage capacity of high-dryness foam in heterogeneous saline aquifers

作　　者：李松岩[1] 马芮 党法强 LI Songyan;MA Rui;DANG Faqiang(School of Petroleum Engineering,China University of Petroleum(East China),Qingdao,Shandong 266580,China)

机构地区：[1]中国石油大学(华东)石油工程学院

出　　处：《天然气工业》2024年第4期46-55,共10页Natural Gas Industry

基　　金：国家自然科学基金面上项目“CO_(2)非混相驱过程中油基泡沫形成机制及其对CO_(2)流度控制规律”(编号:51774306);“致密油藏纳米孔隙内超临界CO_(2)扩散传质机制研究”(编号:51974346)。

摘　　要：CO_(2)咸水层封存是实现“碳中和”目标的一项重要技术手段。高干度泡沫不仅能更好地控制CO_(2)流度而且还能适应地层的非均质性,明显提高了咸水层的空间利用效率。为探究高干度CO_(2)泡沫在非均质咸水层中的调剖效果与CO_(2)封存能力,利用自行设计的高温高压驱替实验装置,进行了不同渗透率级差的并联岩心CO_(2)泡沫驱室内实验研究,分析了驱替过程中岩心的气液产出情况与CO_(2)饱和度的变化规律,指出了不同渗透率级差非均质岩心模型的碳封存效果与机理。研究结果表明:①与CO_(2)气驱相比高干度泡沫驱用于CO_(2)咸水层埋存具有更大优势,当岩心渗透率级差介于2.6~10.8时,泡沫均能有效封堵高渗透岩心,使阻力因子维持在36左右,增大了驱替压差与低渗透岩心的产气、产液速度;②岩心中气相饱和度与渗透率存在一定关系,当岩心的渗透率小于2450 mD时,最高气相饱和度随渗透率增加而增大,当渗透率超过2450 mD时,岩心最高气相饱和度在80%左右;③采用高干度泡沫驱可以有效扩大岩心中CO_(2)封存量,渗透率级差为4时,泡沫驱的CO_(2)封存体积较气驱增长219%,当渗透率级差扩大至10.8,CO_(2)封存量能始终维持在较高水平。结论认为,咸水层条件下CO_(2)泡沫驱替实验探究了CO_(2)封存能力变化,提供了非均质储层提高碳封存效率的实验认识,可为非均质咸水层中CO_(2)的地质封存技术优化提供参考和借鉴。CO_(2) storage in saline aquifers is an important technical means to achieve the goal of"carbon neutrality".High-dryness foam can not only control CO_(2) mobility,but also adapt to heterogeneous reservoirs,so it can improve the space utilization efficiency of saline aquifers.In order to explore the profile control effect and CO_(2) storage capacity of high-dryness CO_(2) foam in heterogeneous saline aquifers,this paper performs laboratory experiments to study CO_(2) foam displacement in parallel cores with different permeability contrasts by using our independently designed high-temperature and high-pressure displacement experiment device.In addition,the gas and liquid production situations and the change laws of CO_(2) saturation in the cores during the displacement process are analyzed,and the carbon storage effects and mechanisms in heterogeneous core model with different permeability contrasts are revealed.And the following research results are obtained.First,compared with CO_(2) flooding,high-dryness foam flooding is more advantageous for saline aquifer CO_(2) storage.When the permeability contrast of the cores is in the range of 2.6-10.8,foam can effectively block the high-permeability cores and maintain the resistance factor at about 36,so as to increase the displacement pressure difference and the gas and liquid production rates of low-permeability cores.Second,there is a certain relationship between gas saturation and permeability of cores.When the permeability is less than 2450 mD,the highest gas saturation increases with the increasing of permeability.When the permeability exceeds 2450 mD,the highest gas saturation is about 80%.Third,high-dryness foam flooding can effectively expand the CO_(2) storage volume in the cores.When the permeability contrast is 4,the CO_(2) storage volume by foam flooding is 219%larger than that by gas flooding.When the permeability contrast is high up to 10.8,the CO_(2) storage volume can be maintained at a high level all the time.In conclusion,the CO_(2) foam displacement e

关 键 词：碳中和 CO_(2)地质封存 高干度泡沫 咸水层 非均质地层 封存效率 

分 类 号：TE822[石油与天然气工程—油气储运工程]