An Economic, Field-Proven Method For Removing Fines Damage From Gravel Packs

Abstract

An Economic, Field-Proven Method For Removing Fines Damage From Gravel Packs F.O. Stanley; F.O. Stanley BJ Services Co. Indonesia Search for other works by this author on: This Site Google Scholar J.C. Troncoso; J.C. Troncoso YPF-Maxus Southeast Sumatra B.V. Search for other works by this author on: This Site Google Scholar A.N. Martin; A.N. Martin BJ Services Co. (Singapore) Search for other works by this author on: This Site Google Scholar Omar Ali Jamil Omar Ali Jamil Brunei Shell Petroleum Search for other works by this author on: This Site Google Scholar Paper presented at the SPE International Symposium on Formation Damage Control, Lafayette, Louisiana, February 2000. Paper Number: SPE-58790-MS https://doi.org/10.2118/58790-MS Published: February 23 2000 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Stanley, F.O., Troncoso, J.C., Martin, A.N., and Omar Ali Jamil. "An Economic, Field-Proven Method For Removing Fines Damage From Gravel Packs." Paper presented at the SPE International Symposium on Formation Damage Control, Lafayette, Louisiana, February 2000. doi: https://doi.org/10.2118/58790-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 International Conference and Exhibition on Formation Damage Control Search Advanced Search AbstractIt's a fact of life—many gravel packs plug up. As time passes, skin factors go up and production rates go down. Much of the money that was spent on creating a sand control completion with minimum skin may eventually count for nothing. In order to prolong the effectiveness of the gravel pack (GP) and as a added benefit reduce the need for work overs, a method was developed in the Far East to remove these fines and dramatically reduce the skin factor. The method employs relatively small volumes of a specialized HF (hydrogen fluoride) acid system, designed to penetrate into the GP and very near wellbore area. The HF acid system uses an organo-phosphonate (HV) acid to control the production of HF and to control and drastically reduce potentially damaging secondary and tertiary precipitates. The system will be referred to as HV:HF Acid in this paper.This HV:HF Acid system can be applied to any well with a screen and/or GP that has damage caused by the migration of formation fines and/or drilling mud particles. It is not limited by the type of screen or gravel nor by the length or number of sets of screens. The method has potentially enormous implications throughout the world. Any well with a GP or screen could potentially benefit from this method of treatment, including long horizontal intervals, which up to now have been very expensive to treat, due to the larger volumes of acid normally recommended.The results of this HV:HF Acid method will be illustrated by 3 case histories from the Far East, including horizontal wells. The observations from these treatments allow us to conclude that this method is highly successful, cost effective, and applicable to a broad spectrum of well conditions. The reduced stimulation volumes provide better economics, so that even long sections and horizontal wells can now be stimulated at reasonable costs.IntroductionAround the world there are literally thousands of gravel packed wells which could benefit from a reliable and cost effective method for removing damage caused by fines. Many of these wells start out with relatively low skin factors and then gradually show an increase in skin as the GP, a.k.a. "the filter", collects migrating particulates. In other areas of the oil industry where filters are used (hydraulic systems, preparation of completion fluids, engine lubrication etc), filters are cleaned or replaced as they get plugged. Replacing a GP is a risky and expensive process which involves the often problematic well killing operation. Alternatively, cleaning the GP has the potential to be a much more cost effective solution.There are inherent problems associated with trying to remove fines damage from the matrix of a GP. Firstly, the fines themselves are usually composed of either quartz particles (silica), silicates and alumino-silicates (clays and feldspars) or, more commonly, a combination of these. Because the GP is filtering out some of these particles, they are generally much more concentrated in the GP area than they originally were in the formation. The only method available for removing these fines—short of doing a work over—is to use some kind of hydrogen fluoride (HF) based acid system, typically referred to as "mud acid" (as these acid systems were first developed to remove formation damage caused by drilling muds). The use of such acid systems to dissolve silica, silicates and alumino-silicates is sometimes poorly understood and can often result in the production of several different types of precipitates. Indeed, the process of HF acidizing has been described as an effort to remove more damage than the damage created by the treatment itself.1 Instances of HF treatments actually reducing production (i.e. creating more damage than they remove) are unacceptably common. Keywords: acid stage, completion installation and operations, well intervention, drilling fluid formulation, acidizing, bopd, acid system, drilling fluids and materials, nh 4cl, stimulation Subjects: Drilling Fluids and Materials, Drilling fluid selection and formulation (chemistry, properties), Acidizing, Completion Installation and Operations, Well Intervention, Well Operations, Optimization and Stimulation This content is only available via PDF. 2000. Society of Petroleum Engineers You can access this article if you purchase or spend a download.