储层条件下CO2-水岩反应对砂岩储层地化性质影响研究

doi:10.13809/j.cnki.cn32-1825/te.2025.04.002

油气藏评价与开发 ›› 2025, Vol. 15 ›› Issue (4): 545-553.doi: 10.13809/j.cnki.cn32-1825/te.2025.04.002

储层条件下CO₂-水岩反应对砂岩储层地化性质影响研究

张超¹(), 朱鹏宇², 黄天镜¹, 鄢长灏³, 柳洁⁴, 王博¹, 张斌⁵, 张益⁵()

1.中国石油长庆油田分公司勘探开发研究院，陕西西安 710018
2.中国石油塔里木油田分公司，新疆库尔勒 841000
3.中国石油长庆油田分公司油气工艺研究院，陕西西安 710018
4.中国石油长庆油田分公司第三采气厂，内蒙古鄂尔多斯 017300
5.西安石油大学石油工程学院，陕西西安 710065

收稿日期:2024-07-09 发布日期:2025-07-19 出版日期:2025-08-26
通讯作者: 张益（1979—），男，博士，教授，主要从事油气藏渗流理论与数值模拟技术、油气田开发理论与方法和CO₂驱油与地质封存方面的科研工作。地址：陕西省西安市电子二路西安石油大学石油工程学院，邮政编码：710065。E-mail：zhy@xsyu.edu.cn
作者简介:张超（1992-），男，硕士，高级工程师，主要从事页岩油开发研究工作。地址：陕西省西安市未央区凤城四路中国石油长庆油田分公司勘探开发研究院，邮政编码：710018。Email：zhangch46_cq@petrochina.com.cn
基金资助:
国家科技重大专项“地球深部探测与矿产资源勘查”(2024ZD1004406);中国石油攻关性应用性科技专项“陆相页岩油开发优化技术研究与试验”(2023ZZ15YJ03);中国石油长庆油田分公司重大专项“鄂尔多斯盆地页岩油渗流机理及有效开发关键技术研究”(2023DZZ04);陕西省重点研发计划“高含水油藏CO2驱开发过程中的渗流及碳埋存规律研究与应用”(2023-YBGY-316)

Study on the influence of CO₂-water-rock reactions under reservoir conditions on geochemical properties of sandstone reservoirs

ZHANG Chao¹(), ZHU Pengyu², HUANG Tianjing¹, YAN Changhao³, LIU Jie⁴, WANG Bo¹, ZHANG Bin⁵, ZHANG Yi⁵()

1.Research Institute of Exploration and Development, PetroChina Changqing Oilfield Company, Xi’an, Shaanxi 710018, China
2.PetroChina Tarim Oilfield Company, Korla, Xinjiang 841000, China
3.Oil and Gas Technology Research Institute, PetroChina Changqing Oilfield Company, Xi’an, Shaanxi 710018, China
4.Third Gas Production Plant, PetroChina Changqing Oilfield Company, Ordos, Inner Mongolia 017300, China
5.College of Petroleum Engineering, Xi’an Shiyou University, Xi’an, Shaanxi 710065, China

Received:2024-07-09 Online:2025-07-19 Published:2025-08-26

摘要/Abstract

摘要：

国内现采用CO₂驱油的油田多为水驱后转入注CO₂开发，长时间作用下CO₂-水岩反应造成储层物性条件变化成为必须考虑的问题之一，为解决目前CO₂-水岩反应相关研究存在反应时间较短，环境变量对CO₂-水岩反应的影响不清等问题，利用高温高压反应釜模拟储层环境，采用高性能场发射扫描电镜和X射线衍射仪等设备，研究不同环境变量下CO₂-水岩反应对储层物性与矿物成分等的影响及其作用机理。实验结果表明：CO₂-水岩反应后，长石类矿物的溶蚀和黏土矿物的生成是影响储层物性的主要因素。随着实验温度升高，水岩反应加剧，钾长石、钙长石与钠长石加速溶解，高岭石占比增加，储层物性改善。压力增加时，大量CO₂的溶解降低了溶液的pH值，抑制了钾长石、钠长石等矿物向高岭石等黏土矿物的转化，储层整体物性变差。随着反应时间的延长，长石与碳酸盐岩类矿物溶蚀加剧，Na⁺、K⁺、Ca²⁺等主要离子质量浓度上升，储层物性改善且有石膏生成。在实验范围内，CO₂-水岩反应对矿物的溶蚀程度与温度、时间呈正相关，与注入压力呈负相关。最后，利用Kozeny-Carman方程对实验结果进行计算，结果表明在实验范围内，储层孔渗物性与温度、时间呈正相关，与CO₂注入压力呈负相关。通过研究不同环境变量下CO₂-水岩反应对储层的影响，对CO₂驱油提高采收率在页岩油矿场的应用提供了参考。

关键词: CCUS-EOR, CO₂驱替, 水岩反应, 地化性质, 孔喉变化

Abstract:

Most oilfields currently using CO₂ flooding in China have transitioned from water flooding to CO₂ injection for development. Over prolonged periods, CO₂-water-rock reactions can alter reservoir physical properties, becoming a key issue that must be addressed. To address limitations in existing studies—such as short reaction durations and unclear effects of environmental variables—this research used a high-temperature, high-pressure reactor to simulate reservoir conditions. Advanced equipment, including high-performance field-emission scanning electron microscope and X-ray diffraction, was utilized to study the effects and mechanisms of CO₂-water-rock reactions on reservoir physical properties and mineral compositions under different environmental variables. The experimental results indicated that feldspar dissolution and clay mineral formation were the primary factors affecting reservoir physical properties after CO₂-water-rock reactions. With increasing temperature, the water-rock reaction intensified, accelerating the dissolution of potassium feldspar, calcium feldspar, and sodium feldspar while increasing the proportion of kaolinite, thereby improving reservoir physical properties. When pressure increased, the dissolution of large amounts of CO₂ lowered the solution pH and inhibited the transformation of minerals such as potassium feldspar and sodium feldspar into clay minerals like kaolinite, causing deterioration in overall reservoir physical properties. As the reaction time increased, the dissolution of feldspar and carbonate minerals intensified, leading to increased mass concentrations of major ions such as Na⁺, K⁺, Ca²⁺, an improvement in reservoir physical properties, and the precipitation of gypsum. Within the experimental range, the degree of mineral dissolution caused by CO₂-water-rock reactions exhibited a positive correlation with temperature and time but a negative correlation with injection pressure. Finally, the experimental results were calculated using the Kozeny-Carman equation, indicating that within the experimental range, reservoir porosity and permeability are positively correlated with temperature and time, and negatively correlated with CO₂ injection pressure. By studying the impact of CO₂-water-rock reactions on reservoirs under different environmental variables, this study offers insights for the application of CO₂ flooding to enhance oil recovery (EOR) in shale oil reservoirs.

Key words: CCUS-EOR, CO₂ flooding, water-rock reaction, geochemical properties, pore-throat alteration

中图分类号:

TE343

张超,朱鹏宇,黄天镜, 等. 储层条件下CO₂-水岩反应对砂岩储层地化性质影响研究[J]. 油气藏评价与开发, 2025, 15(4): 545-553.

ZHANG Chao,ZHU Pengyu,HUANG Tianjing, et al. Study on the influence of CO₂-water-rock reactions under reservoir conditions on geochemical properties of sandstone reservoirs[J]. Petroleum Reservoir Evaluation and Development, 2025, 15(4): 545-553.

图/表 23

图1

表1

地层水的离子质量浓度"

层位	离子质量浓度/（mg/L）								总矿化度/（mg/L）	水型
层位	K⁺Na⁺	Ca²⁺	Mg²⁺	Ba²⁺	Cl^-	HCO $3 -$	SO $4 2 -$	CO $3 2 -$	总矿化度/（mg/L）	水型
长8	14 700	2 090	236	489	27 100	0	515	0	45 130	CaCl₂

表1

图2

表2

表3

表4

图3

表5

图4

表6

表7

表8

图5

图6

图7

表9

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表11

图8

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表15

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岩心编号	直径/cm	长度/cm	孔隙度/%	渗透率/10^-3 μm²
A6	2.51	4.38	9.35	0.183
B6	2.50	5.02	8.83	0.083
B7	2.51	4.94	8.86	0.053

岩心编号	岩心片编号	岩心片厚度/cm	岩心粉末编号	岩心粉末重量/g
A6	a6		A6-1	15.1
		0.48	A6-2	14.8
			A6-3	15.2
B6	b6		B6-1	14.7
		0.52	B6-2	14.9
			B6-3	15.2
B7	b7		B7-1	15.1
		0.49	B7-2	15.1
			B7-3	15.3

岩心片编号	岩心粉末编号	实验温度/℃	实验压力/MPa	反应时间/d
a6	A6-1	60	15	14
	A6-2	75	15	14
	A6-3	85	15	14
b6	B6-1	85	15	14
	B6-2	85	20	14
	B6-3	85	25	14
b7	B7-1	85	25	14
	B7-2	85	25	21
	B7-3	85	25	28

样品编号	实验温度/℃	主要离子质量浓度/（mg/L）
样品编号	实验温度/℃	Na⁺	K⁺	Ca²⁺	Mg²⁺	Ba²⁺
A6-1	60	36 861	4 556	4 058	249	1 389.90
A6-2	75	34 942	4 837	4 137	251	1 491.42
A6-3	85	37 715	4 983	4 161	253	1 560.78

样品编号	实验温度/℃	主要矿物组分占比
样品编号	实验温度/℃	黏土矿物	石英	钾长石	斜长石	方解石	白云石	石盐
原始样		8.8	24.6	26.1	40.0	0.5	0	0
A6-1	60	7.5	18.3	25.6	46.8	0.3	1.6	1.3
A6-2	75	8.9	16.5	3.1	68.8	0.2	0	2.2
A6-3	80	10.5	26.4	15.2	43.1	0	0.3	3.4

储层条件下CO₂-水岩反应对砂岩储层地化性质影响研究

Study on the influence of CO₂-water-rock reactions under reservoir conditions on geochemical properties of sandstone reservoirs

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样品编号	实验温度/℃	主要黏土矿物组分
样品编号	实验温度/℃	高岭石	绿泥石	伊利石	伊/蒙间层	伊/蒙间层比
原始样品		19.9	74.6	3.7	1.8	10
A6-1	60	23.1	71.3	3.2	2.4	10
A6-2	75	27.6	67.0	3.7	1.7	10
A6-3	80	33.7	59.7	4.6	2.0	10

样品编号	实验时间/d	主要离子质量浓度/（mg/L）
样品编号	实验时间/d	Na⁺	K⁺	Ca²⁺	Mg²⁺	Ba²⁺
B7-1	14	31 943.46	4 264.80	4 057.20	253.76	1 389.92
B7-2	21	36 811.90	4 533.80	4 455.20	268.54	1 556.60
B7-3	28	40 970.34	5 463.88	4 606.44	279.82	1 673.44

反应矿物	密度	反应矿物	密度
石英	2.65	石盐	2.16
钾长石	2.54	高岭石	2.63
斜长石	2.76	绿泥石	3.30
方解石	5.61	伊利石	2.90
白云石	2.80	石膏	2.32

样品编号	实验温度/℃	实验压力/MPa	实验时间/d	计算孔隙度/%	计算渗透率/10^-3 μm²
A6-1	60	15	14	0.071	0.110
A6-2	70	15	14	0.110	0.286
A6-3	80	15	14	0.114	0.314
B6-1	85	15	14	0.347	2.416
B6-2	85	20	14	0.232	0.777
B6-3	85	25	14	0.188	0.459
B7-1	85	25	14	0.141	0.142
B7-2	85	25	21	0.166	0.210
B7-3	85	25	28	0.180	0.246

[1]	吴潇, 刘润昌. CO₂作用下碳酸盐岩物性及孔喉结构变化特征 [J]. 油气藏评价与开发, 2025, 15(4): 571-578.
[2]	李士伦,孙雷,陈祖华,李健,汤勇,潘毅. 再论CO₂驱提高采收率油藏工程理念和开发模式的发展 [J]. 油气藏评价与开发, 2020, 10(3): 1-14.

样品编号	实验压力/MPa	主要离子质量浓度/（mg/L）
样品编号	实验压力/MPa	Na⁺	K⁺	Ca²⁺	Mg²⁺	Ba²⁺
B6-1	15	41 591.12	5 388.78	4 063.28	260.28	1 517.92
B6-2	20	36 208.56	4 901.88	4 184.66	268.26	1 523.74
B6-3	25	35 679.02	3 800.12	4 474.04	262.24	1 472.08

样品编号	实验时间/d	主要矿物组分
样品编号	实验时间/d	黏土矿物	石膏	石英	钾长石	斜长石	方解石	白云石	石盐
原始样		13.2	0	36.1	6.7	41.6	2.4	0	0
B7-1	14	10.5	0	21.3	14.4	49.4	0.3	0	0.9
B7-2	21	11.5	1.2	24.5	9.5	48.1	0.7	0	3.9
B7-3	28	12.7	1.2	24.7	10.8	48.4	1.0	0	3.2

样品编号	实验时间/d	主要黏土矿物组分
样品编号	实验时间/d	高岭石	绿泥石	伊利石	伊/蒙间层	伊/蒙间层比
原始样品		34.1	61.4	3.3	1.2	10
B7-1	14	21.2	74.0	2.9	1.9	10
B7-2	21	23.7	71.6	2.5	2.2	10
B7-3	28	27.5	67.5	3.5	1.5	10