Sweep Improvement in CO2-IOR Through Direct CO2 Viscosification

Afra, Salar; Firoozabadi, Abbas

doi:10.2118/210124-ms

Cited by 3 publications

(1 citation statement)

References 24 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Using chemical plugging to delay or control CO 2 channeling is an effective method in oilfield applications . The chemical plugging methods suitable for CO 2 flooding mainly include water–gas alternating injection technology (WAG), foam, polymer gel, CO 2 -responsive thickening polymer (CO 2 -RTP), precipitation system, small molecular amine system, etc. − Among them, WAG, foam, and polymer gel are widely used in the field or have great potential. − The first field application of the WAG system was in the North Pembina oil field in Canada in 1957 .…”

Section: Introductionmentioning

confidence: 99%

Experimental Evaluation of Combined Plugging System for CO₂-Improved Oil Recovery and Storage

Chen

et al. 2023

Energy Fuels

View full text Add to dashboard Cite

High-performance CO 2 -improved oil recovery (IOR) and storage technology is one of the most promising measures for global oilfield companies to achieve zero carbon targets. Due to the severe heterogeneity of most petroleum reservoirs and the significant density difference between CO 2 and reservoir fluid, the efficiency of CO 2 -IOR and storage is usually limited. In this paper, a hightemperature and high-pressure 30 cm core displacement experiment was used to study the CO 2 conformance control performance of both the single-and the combined plugging system in long sandstone cores. The single systems evaluated included polymer gels, CO 2 foams, and CO 2 -responsive thickening polymer (CO 2 -RTP) systems. The combined systems were pairwise combinations of the three of them. Results show that the pressure rise and maximum breakthrough pressure of the gel system were the highest among three single-plugging systems. Its plugging efficiency was the highest, reaching 86.13%. At the same time, its gas production reduction rate was also the highest, reaching 95.71%. In the parallel 30 cm core plugging experiments, three combined plugging systems all showed excellent plugging and CO 2 conformance improvement performance. Among them, the combined plugging systems containing polymer gels had larger plugging efficiency, and their gas production reduction ratios reached about 90%. Compared with single systems, the combined plugging systems had the advantages of easy injection and in-depth propagation, which can significantly improve CO 2 conformance and oil recovery. The research results of this study can provide the experimental understanding and theoretical guidance for the current tricky oilfield problems of CO 2 channeling.

show abstract

Section: Introductionmentioning

confidence: 99%

Experimental Evaluation of Combined Plugging System for CO₂-Improved Oil Recovery and Storage

Chen

et al. 2023

Energy Fuels

View full text Add to dashboard Cite

show abstract

Real-Time 3D Imaging of Neat, and Viscosified CO2 in Displacement of Brine-Saturated Porous Media

Ding,

Kantzas,

Firoozabadi

2023

Day 2 Tue, October 17, 2023

View full text Add to dashboard Cite

CO2 storage in saline aquifers may contribute to a 95% share in preventing emissions to the atmosphere. The process is inefficient due to low CO2 viscosity at the subsurface conditions. Most of the injected CO2 will spread quickly at the formation top and increase the probability of leakage. This work is aimed to demonstrate improved CO2 storage in saline aquifers by effective viscosification/thickening of the sc-CO2 at very low concentrations of engineered polymers and by slug injection. We also present results from X-ray CT imaging to advance the understanding of two-phase CO2-brine flow in porous media and firmly establish the transport mechanisms. X-ray CT imaging of displacement experiments is conducted to quantify the in-situ sc-CO2 saturation spatiotemporally in brine-saturated Berea sandstone cores. In neat CO2 injection, gravity override and viscous fingering result in early breakthrough and low sweep efficiency. Cumulative brine production is approximately 30% (from fraction collector) and 35% (from X-ray CT imaging) at 2 PVI. The difference between the two is attributed to the solubility of the produced water in the produced CO2 at atmospheric pressure which has been neglected in the past. We show that when the forgotten effect is accounted for, there is a good agreement between direct measurements and in-situ saturation results. In the past, we have demonstrated that effectiveness of an oligomer of poly(1-decene) in displacement of brine by CO2 at a concentration of 1.5 wt.%. In this work, we show that the same polymer is effective at low concentration of 0.6 wt.%. The oligomer slows the breakthrough by 1.6 times and improves the brine production by 35% in horizontal orientation. Such a large effect is thought to be from the increase of the interfacial elasticity, based on the X-ray CT imaging of displacement experiments. We also show that there is no need for continuous injection of the oligomer. A slug of 0.3 PVI viscosified CO2 followed by neat CO2 injection has the same effectiveness as the continuous injection of the neat CO2. In this work, we also demonstrate the effectiveness of an engineered new molecule at 0.3 wt.% that may increase residual trapping by about 30%. The new molecule has much higher effectiveness than our recent molecule. The combination of mobility control and residual brine saturation reduction is expected to improve the CO2 storage in saline aquifers by effective viscosificaiton with low concentrations of oligomers.

show abstract

Spatiotemporal X-Ray Imaging of Neat and Viscosified CO2 in Displacement of Brine-Saturated Porous Media

Ding,

Kantzas,

Firoozabadi

2024

SPE Journal

View full text Add to dashboard Cite

Summary CO2 storage in saline aquifers may contribute to a 90% share in preventing emissions to the atmosphere. Due to low CO2 viscosity at the subsurface often found in supercritical (sc) conditions, the injected CO2 may spread quickly at the formation top and increase the probability of leakage. This work relates to improved CO2 storage in saline aquifers by effective viscosification of the sc-CO2 at very low concentrations of engineered oligomers and the effectiveness of slug injection of viscosified CO2 (vis-CO2). We present the results from X-ray computed tomography (CT) imaging to advance the understanding of two-phase CO2-brine flow in porous media and firmly establish the transport mechanisms. X-ray CT imaging of displacement experiments is conducted to quantify the in-situ sc-CO2 saturation spatiotemporally. In neat CO2 injection, gravity override and adverse mobility ratio may result in early breakthrough and low sweep efficiency. We find cumulative brine production from the fraction collector to be lower than X-ray CT imaging at 2 pore volume (PV) injection. The difference between the two is attributed to the solubility of the produced water in the produced CO2 at atmospheric pressure. We show that when the solubility is accounted for, there is a good agreement between direct measurements and in-situ saturation results. There are three reports (two by the same group) that oligomers of 1-decene (O1D) with six repeat units may have marginal CO2 viscosification. The majority of published work by other groups shows that O1D with six repeat units and higher are effective CO2 viscosifiers. In the past, we have demonstrated the effectiveness of an O1D in the displacement of brine by CO2 at a concentration of 1.5 wt%. The effectiveness is examined and identified by three different methods. In this work, we show that the same oligomer is effective at a low concentration of 0.6 wt%. The oligomer slows the breakthrough by 1.6 times and improves the brine production by 34% in the horizontal orientation. X-ray CT imaging results reveal that such a large effect may be from the increase in the interfacial elasticity. We also show that there is no need for continuous injection of the oligomer. A slug of 0.3 PV injection (PVI) of vis-CO2 followed by neat CO2 injection has the same effectiveness as the continuous injection of the vis-CO2. In this work, we also demonstrate the effectiveness of a new engineered molecule at 0.3 wt% that may increase residual trapping by about 35%. The combination of mobility control and residual brine saturation reduction is expected to improve CO2 storage by effective viscosification with low concentrations of oligomers.

show abstract

Sweep Improvement in CO2-IOR Through Direct CO2 Viscosification

Cited by 3 publications

References 24 publications

Experimental Evaluation of Combined Plugging System for CO₂-Improved Oil Recovery and Storage

Experimental Evaluation of Combined Plugging System for CO₂-Improved Oil Recovery and Storage

Real-Time 3D Imaging of Neat, and Viscosified CO2 in Displacement of Brine-Saturated Porous Media

Spatiotemporal X-Ray Imaging of Neat and Viscosified CO2 in Displacement of Brine-Saturated Porous Media

Contact Info

Product

Resources

About

Sweep Improvement in CO2-IOR Through Direct CO2 Viscosification

Cited by 3 publications

References 24 publications

Experimental Evaluation of Combined Plugging System for CO2-Improved Oil Recovery and Storage

Experimental Evaluation of Combined Plugging System for CO2-Improved Oil Recovery and Storage

Real-Time 3D Imaging of Neat, and Viscosified CO2 in Displacement of Brine-Saturated Porous Media

Spatiotemporal X-Ray Imaging of Neat and Viscosified CO2 in Displacement of Brine-Saturated Porous Media

Contact Info

Product

Resources

About

Experimental Evaluation of Combined Plugging System for CO₂-Improved Oil Recovery and Storage

Experimental Evaluation of Combined Plugging System for CO₂-Improved Oil Recovery and Storage