An Experimentally Validated Wormhole Model for Self-Diverting andConventional Acids in Carbonate Rocks Under Radial Flow Conditions

Abstract

An Experimentally Validated Wormhole Model for Self-Diverting and Conventional Acids in Carbonate Rocks under Radial Flow Conditions Philippe Michel Jacques Tardy; Philippe Michel Jacques Tardy Schlumberger Search for other works by this author on: This Site Google Scholar Bruno Lecerf; Bruno Lecerf Schlumberger Search for other works by this author on: This Site Google Scholar Yenny Christanti Yenny Christanti Schlumberger Search for other works by this author on: This Site Google Scholar Paper presented at the European Formation Damage Conference, Scheveningen, The Netherlands, May 2007. Paper Number: SPE-107854-MS https://doi.org/10.2118/107854-MS Published: May 30 2007 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Tardy, Philippe Michel Jacques, Lecerf, Bruno, and Yenny Christanti. "An Experimentally Validated Wormhole Model for Self-Diverting and Conventional Acids in Carbonate Rocks under Radial Flow Conditions." Paper presented at the European Formation Damage Conference, Scheveningen, The Netherlands, May 2007. doi: https://doi.org/10.2118/107854-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search Dropdown Menu nav search search input Search input auto suggest search filter All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)SPE European Formation Damage Conference and Exhibition Search Advanced Search AbstractSelf-diverting acids are commonly used in matrix acidizing treatments of carbonate formations, not only to increase permeability by generating wormholes, as with conventional acids such as HCl, but also to self-divert into zones of lower injectivity, in the goal of optimizing zonal coverage. In this paper, a new model for wormhole propagation is proposed, which describes both stimulation and diversion processes.A preliminary model is presented, which predicts wormhole propagation under radial-flow conditions for conventional acids. Then, a new set of parameters characterizing the reactive flow of self-diverting acids is developed, and the above model is extended to include self-diverting mechanisms. In particular, it is shown how the new parameters related to wormhole growth and those to diversion can be assessed from linear core-flood experiments and integrated into a new radial-flow model for field-scale prediction. Using this model, a new criterion is developed for diverter efficiency as a function of permeability contrast. Finally, the model is validated against radial flow experiments.It is found that self-diverting acids are characterized by two new parameters which, when combined with the model for wormhole propagation, can be used to predict the performance of self-diverting acids, both in terms of wormhole penetration and in terms of zonal coverage. Some criteria are also developed to assess the diversion ability of acids.IntroductionModels for predicting wormhole propagation have been widely discussed in the literature. Various types of modeling techniques have been used to describe the wormholing phenomenon:1D-averaged models 1,2,3,4,5Discrete models 6,7,8Darcy-scale 2D and 3D continuum models 9,10Multi-pore scale network models 2,11In this work, we will partly review types 1 and 3 as they encompass most of the existing literature, and as we believe they constitute the most effective and tractable way to describe the wormholing process. All the literature related to wormhole modeling known to the authors refers to conventional acids, i.e., acids whose rheological properties do not change significantly with time. Self-diverting acids have been developed in order to achieve drastic changes in their rheological properties as acid spends. Keywords: complex reservoir, Fluid Dynamics, correlation, flow in porous media, carbonate reservoir, self-diverting acid, acidizing, HCl, experiment, prediction Subjects: Reservoir Fluid Dynamics, Unconventional and Complex Reservoirs, Acidizing, Flow in porous media, Carbonate reservoirs, Well Operations, Optimization and Stimulation This content is only available via PDF. 2007. Society of Petroleum Engineers You can access this article if you purchase or spend a download.