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Title: Appendix for the Final Technical Report - DE FE0009284

Abstract

Carbon capture utilization storage (CCUS) is a potential technology to store anthropogenic emissions for CO 2. Utilization often refers to CO 2-enhanced oil recovery (CO 2-EOR). An important factor in the success of CO 2 storage in saline formations or CO 2-EOR reservoirs is ensuring that the storage occurs safely and is long-term. Assessment of well integrity has become more important for CCS and CO 2-EOR as it has become apparent that wells represent the most likely migration pathway for CO 2 to leave a CCS storage unit or a CO 2-EOR reservoir. Although wells represent a migration pathway they are also the best vehicle for employing technology monitoring CO 2 injection and storage. This contradiction of being a potential migration path and key monitoring technology leads to a need to understand how monitoring wells may be similar or different in comparison to other types of wells with respect to migration risk. The maturation and completion US Department of Energy sponsored research projects presents an opportunity to assess the integrity of monitoring wells that have been exposed to injected CO 2. This paper discusses an integrity assessment of two monitoring wells in an operating CO 2-EOR flood in Mississippi, USA.more » The CFU31F-2 and CFU31F-3 monitoring wells were constructed to test monitoring technologies in and above a commercial CO 2-EOR project. The materials selected and the design of the well were optimized for monitoring. Carbonation in CFU31-F2 was seen as high as 7900 ft, above what was considered top of cement based on the logs. Time-lapse comparison of cement bond amplitude data and acoustic impedance maps show a deterioration of signal that implies a deterioration of cement bond or cement along much of the cemented annulus in the long-string section. Analysis of sidewall cores using XRD and LA-ICP-MS validated the log interpretation by confirming the degradation of cement (carbonation) along the casing-cement interface. The ultrasonic image maps also clearly identify the control lines and monitoring technology attached to the outside of the of the long-string casing on each well studied. The control lines appear as microdebonded or fluid filled vertical features implying that they could act as leakage pathways. The sidewall core through the control line at 10380 ft confirms that CO 2 is migrating along the control line with heavily carbonated cement at the control line interface. LA-ICP-MS and XRD on formation interface of the sidewall cores collected in both wells indicates that CO 2 is also moving of the cement-formation interface. LA-ICP-MS and XRD indicate that the amount carbonation in the center of the cores was less than the carbonation at the interfaces. Indicating that CO 2 is reaching the center of the cores by diffusing in from the interfaces and not migrating up from the reservoir though the porous matrix of the cement. This agrees with Duguid et al. [5] and Carey et al. [1] who have found that the interfaces in the well are more conductive than the porous network of the cement. Both the materials used to construct the well and the decision to attach monitoring technology to the outside of the well may have contributed to the migration of CO 2 along the interfaces. Careful consideration should be given to material selection to ensure that it does not degrade when in contact with the fluids in the reservoir and overlying strata. The addition of the control line on the outside of the casing complicated the cement placement and likely caused no cement to bond to the casing adjacent to the control line leading out of the reservoir. Further study of other wells with external lines should be conducted to see of the results of the construction of CFU31-F2 and -F3 is normal or an exception.« less

Authors:
 [1]
  1. Univ. of Louisiana, Lafayette, LA (United States)
Publication Date:
Research Org.:
Univ. of Louisiana, Lafayette, LA (United States)
Sponsoring Org.:
USDOE Office of Fossil Energy (FE), Oil and Natural Gas (FE-30)
OSTI Identifier:
1358671
Report Number(s):
Final Technical Report Main Reference
DOE Contract Number:
FE0009284
Resource Type:
Other
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES

Citation Formats

Duguid, Andrew. Appendix for the Final Technical Report - DE FE0009284. United States: N. p., 2017. Web.
Duguid, Andrew. Appendix for the Final Technical Report - DE FE0009284. United States.
Duguid, Andrew. 2017. "Appendix for the Final Technical Report - DE FE0009284". United States. doi:. https://www.osti.gov/servlets/purl/1358671.
@article{osti_1358671,
title = {Appendix for the Final Technical Report - DE FE0009284},
author = {Duguid, Andrew},
abstractNote = {Carbon capture utilization storage (CCUS) is a potential technology to store anthropogenic emissions for CO2. Utilization often refers to CO2-enhanced oil recovery (CO2-EOR). An important factor in the success of CO2 storage in saline formations or CO2-EOR reservoirs is ensuring that the storage occurs safely and is long-term. Assessment of well integrity has become more important for CCS and CO2-EOR as it has become apparent that wells represent the most likely migration pathway for CO2 to leave a CCS storage unit or a CO2-EOR reservoir. Although wells represent a migration pathway they are also the best vehicle for employing technology monitoring CO2 injection and storage. This contradiction of being a potential migration path and key monitoring technology leads to a need to understand how monitoring wells may be similar or different in comparison to other types of wells with respect to migration risk. The maturation and completion US Department of Energy sponsored research projects presents an opportunity to assess the integrity of monitoring wells that have been exposed to injected CO2. This paper discusses an integrity assessment of two monitoring wells in an operating CO2-EOR flood in Mississippi, USA. The CFU31F-2 and CFU31F-3 monitoring wells were constructed to test monitoring technologies in and above a commercial CO2-EOR project. The materials selected and the design of the well were optimized for monitoring. Carbonation in CFU31-F2 was seen as high as 7900 ft, above what was considered top of cement based on the logs. Time-lapse comparison of cement bond amplitude data and acoustic impedance maps show a deterioration of signal that implies a deterioration of cement bond or cement along much of the cemented annulus in the long-string section. Analysis of sidewall cores using XRD and LA-ICP-MS validated the log interpretation by confirming the degradation of cement (carbonation) along the casing-cement interface. The ultrasonic image maps also clearly identify the control lines and monitoring technology attached to the outside of the of the long-string casing on each well studied. The control lines appear as microdebonded or fluid filled vertical features implying that they could act as leakage pathways. The sidewall core through the control line at 10380 ft confirms that CO2 is migrating along the control line with heavily carbonated cement at the control line interface. LA-ICP-MS and XRD on formation interface of the sidewall cores collected in both wells indicates that CO2 is also moving of the cement-formation interface. LA-ICP-MS and XRD indicate that the amount carbonation in the center of the cores was less than the carbonation at the interfaces. Indicating that CO2 is reaching the center of the cores by diffusing in from the interfaces and not migrating up from the reservoir though the porous matrix of the cement. This agrees with Duguid et al. [5] and Carey et al. [1] who have found that the interfaces in the well are more conductive than the porous network of the cement. Both the materials used to construct the well and the decision to attach monitoring technology to the outside of the well may have contributed to the migration of CO2 along the interfaces. Careful consideration should be given to material selection to ensure that it does not degrade when in contact with the fluids in the reservoir and overlying strata. The addition of the control line on the outside of the casing complicated the cement placement and likely caused no cement to bond to the casing adjacent to the control line leading out of the reservoir. Further study of other wells with external lines should be conducted to see of the results of the construction of CFU31-F2 and -F3 is normal or an exception.},
doi = {},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 5
}