Quantitative Modeling of Acid Wormholing in Carbonates- What Are the Gaps to Bridge

Handle URI:
http://hdl.handle.net/10754/599427
Title:
Quantitative Modeling of Acid Wormholing in Carbonates- What Are the Gaps to Bridge
Authors:
Qiu, Xiangdong; Zhao, Weishu; Chang, Frank; Dyer, Steve
Abstract:
Carbonate matrix acidization extends a well's effective drainage radius by dissolving rock and forming conductive channels (wormholes) from the wellbore. Wormholing is a dynamic process that involves balance between the acid injection rate and reaction rate. Generally, injection rate is well defined where injection profiles can be controlled, whereas the reaction rate can be difficult to obtain due to its complex dependency on interstitial velocity, fluid composition, rock surface properties etc. Conventional wormhole propagation models largely ignore the impact of reaction products. When implemented in a job design, the significant errors can result in treatment fluid schedule, rate, and volume. A more accurate method to simulate carbonate matrix acid treatments would accomodate the effect of reaction products on reaction kinetics. It is the purpose of this work to properly account for these effects. This is an important step in achieving quantitative predictability of wormhole penetration during an acidzing treatment. This paper describes the laboratory procedures taken to obtain the reaction-product impacted kinetics at downhole conditions using a rotating disk apparatus, and how this new set of kinetics data was implemented in a 3D wormholing model to predict wormhole morphology and penetration velocity. The model explains some of the differences in wormhole morphology observed in limestone core flow experiments where injection pressure impacts the mass transfer of hydrogen ions to the rock surface. The model uses a CT scan rendered porosity field to capture the finer details of the rock fabric and then simulates the fluid flow through the rock coupled with reactions. Such a validated model can serve as a base to scale up to near wellbore reservoir and 3D radial flow geometry allowing a more quantitative acid treatment design.
Citation:
Qiu X, Zhao W, Chang F, Dyer S (2013) Quantitative Modeling of Acid Wormholing in Carbonates- What Are the Gaps to Bridge. SPE Middle East Oil and Gas Show and Conference. Available: http://dx.doi.org/10.2118/164245-ms.
Publisher:
Society of Petroleum Engineers (SPE)
Journal:
SPE Middle East Oil and Gas Show and Conference
Issue Date:
2013
DOI:
10.2118/164245-ms
Type:
Conference Paper
Sponsors:
The authors would like to thank Jamaliah Abu’Rabie – PhD student of King Abdullah University of Science and Technology (KAUST) for much of the reaction kinetics experimentation used in this study as part of a summer internship program, and Mohammed Abdul Muqtadir of Schlumberger’s Dhahran Research Center for all aspects of the experimentation, core flow and reaction kinetics. Additional aknowledgements go to Sarmad Khan and his supervisor, Dr Abdullah Sultan of King Fahd University of Petroleum and Minerals (KFUPM) for assisting in the experimentation and core CT scanning.
Appears in Collections:
Publications Acknowledging KAUST Support

Full metadata record

DC FieldValue Language
dc.contributor.authorQiu, Xiangdongen
dc.contributor.authorZhao, Weishuen
dc.contributor.authorChang, Franken
dc.contributor.authorDyer, Steveen
dc.date.accessioned2016-02-28T05:50:55Zen
dc.date.available2016-02-28T05:50:55Zen
dc.date.issued2013en
dc.identifier.citationQiu X, Zhao W, Chang F, Dyer S (2013) Quantitative Modeling of Acid Wormholing in Carbonates- What Are the Gaps to Bridge. SPE Middle East Oil and Gas Show and Conference. Available: http://dx.doi.org/10.2118/164245-ms.en
dc.identifier.doi10.2118/164245-msen
dc.identifier.urihttp://hdl.handle.net/10754/599427en
dc.description.abstractCarbonate matrix acidization extends a well's effective drainage radius by dissolving rock and forming conductive channels (wormholes) from the wellbore. Wormholing is a dynamic process that involves balance between the acid injection rate and reaction rate. Generally, injection rate is well defined where injection profiles can be controlled, whereas the reaction rate can be difficult to obtain due to its complex dependency on interstitial velocity, fluid composition, rock surface properties etc. Conventional wormhole propagation models largely ignore the impact of reaction products. When implemented in a job design, the significant errors can result in treatment fluid schedule, rate, and volume. A more accurate method to simulate carbonate matrix acid treatments would accomodate the effect of reaction products on reaction kinetics. It is the purpose of this work to properly account for these effects. This is an important step in achieving quantitative predictability of wormhole penetration during an acidzing treatment. This paper describes the laboratory procedures taken to obtain the reaction-product impacted kinetics at downhole conditions using a rotating disk apparatus, and how this new set of kinetics data was implemented in a 3D wormholing model to predict wormhole morphology and penetration velocity. The model explains some of the differences in wormhole morphology observed in limestone core flow experiments where injection pressure impacts the mass transfer of hydrogen ions to the rock surface. The model uses a CT scan rendered porosity field to capture the finer details of the rock fabric and then simulates the fluid flow through the rock coupled with reactions. Such a validated model can serve as a base to scale up to near wellbore reservoir and 3D radial flow geometry allowing a more quantitative acid treatment design.en
dc.description.sponsorshipThe authors would like to thank Jamaliah Abu’Rabie – PhD student of King Abdullah University of Science and Technology (KAUST) for much of the reaction kinetics experimentation used in this study as part of a summer internship program, and Mohammed Abdul Muqtadir of Schlumberger’s Dhahran Research Center for all aspects of the experimentation, core flow and reaction kinetics. Additional aknowledgements go to Sarmad Khan and his supervisor, Dr Abdullah Sultan of King Fahd University of Petroleum and Minerals (KFUPM) for assisting in the experimentation and core CT scanning.en
dc.publisherSociety of Petroleum Engineers (SPE)en
dc.titleQuantitative Modeling of Acid Wormholing in Carbonates- What Are the Gaps to Bridgeen
dc.typeConference Paperen
dc.identifier.journalSPE Middle East Oil and Gas Show and Conferenceen
dc.contributor.institutionSchlumberger Middle East SA.en
dc.contributor.institutionSchlumbergeren
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