Nonacid Solution for Mineral Scale Removal in Downhole Conditions Yamile Sanchez; Yamile Sanchez Nalco Company Search for other works by this author on: This Site Google Scholar Eber Castro Neira; Eber Castro Neira BP Search for other works by this author on: This Site Google Scholar David Reyes; David Reyes Nalco de Colombia, LTDA Search for other works by this author on: This Site Google Scholar Carlos Macias; Carlos Macias Nalco de Colombia, LTDA Search for other works by this author on: This Site Google Scholar Hernan Gutierrez; Hernan Gutierrez Nalco de Colombia, LTDA Search for other works by this author on: This Site Google Scholar Jose Reyes; Jose Reyes Search for other works by this author on: This Site Google Scholar Neil D. Feasey; Neil D. Feasey Nalco Company Search for other works by this author on: This Site Google Scholar Raul Diaz; Raul Diaz Nalco Company Search for other works by this author on: This Site Google Scholar Sandra Linares-samaniego Sandra Linares-samaniego Nalco Company Search for other works by this author on: This Site Google Scholar Paper presented at the Offshore Technology Conference, Houston, Texas, May 2009. Paper Number: OTC-20167-MS https://doi.org/10.4043/20167-MS Published: May 04 2009 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Sanchez, Yamile, Neira, Eber Castro, Reyes, David, Macias, Carlos, Gutierrez, Hernan, Reyes, Jose, Feasey, Neil D., Diaz, Raul, and Sandra Linares-samaniego. "Nonacid Solution for Mineral Scale Removal in Downhole Conditions." Paper presented at the Offshore Technology Conference, Houston, Texas, May 2009. doi: https://doi.org/10.4043/20167-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search nav search search input Search input auto suggest search filter All ContentAll ProceedingsOffshore Technology ConferenceOTC Offshore Technology Conference Search Advanced Search AbstractMineral scales, in particular calcite (CaCO3) and siderite (FeCO3) have been associated with formation damage in oil fields in Colombia. Scale deposition has been observed within the production flowline as well as in the formation.For many years, this scale problem has been addressed through the use of traditional acid treatments. However, this approach caused additional problems such as re-precipitation due to spent acid, clay swelling, and corrosion, giving rise to rapid losses in production, fine migration, and asset integrity concerns.With this in mind, a process to identify the Best in Class non-acid scale dissolver was developed. Through this process, the service company developed a new alternative based on a material with neutral pH, high dissolution capacity, and no reprecipitation. After thorough laboratory evaluation and testing, the product was successfully applied in the field. The first six applications allowed an increase in crude production of approximately 300,000 bbl.This paper details the methodology developed for evaluation and selection of the Best in Class scale dissolver used in this application, as well as the development and implementation of the strategy that allowed the successful field application of the selected material. The practical improvements achieved through this approach and how the approach can be used to develop effective troubleshooting and improvement processes will be discussed.IntroductionThe formation of mineral scale within the near wellbore area, production tubing, and topside process equipment presents a challenge to the oil and gas industry. The precipitation of mineral scale is a common cause of formation damage during the production of hydrocarbons and can cause significant production decline (Cowan et al., 1976). Carbonate scales (calcite, CaCO3, and siderite, FeCO3) can be formed due to pressure or temperature changes. Sulfate scales, on the other hand, are typically formed due to the mixing of incompatible waters. Scale problems are normally managed by the application of scale inhibitors. There are, however, some instances where scale inhibition alone is not sufficient to prevent production decline due to scale deposition. In these cases, scale removal using scale dissolvers may be required (Clemmit et al., 1985).Scale dissolvers are typically aqueous solutions of either acids/chelants for carbonate scale or alkaline chelating agents for sulfate scales (Fredd et al., 1998; Frenier, 2001; Benson et al., 1997; Weintritt et al., 1967; Schutte, 1987; Clemmit et al., 1985; Jordan et al., 2006) also, carbonate scale can be removed by using corrosion-inhibited hydrochloric acid (Bakken et al., 1996; Ramstad, 1997; Benson et al., 1997; Rhudy, 1993).This paper will focus on the chemical removal of calcite and siderite scale associated with formation damage in oil fields in Colombia and the process used to develop a scale control strategy that includes the use of a material with neutral pH, high dissolution capacity, and no re-precipitation issues. Keywords: application, oilfield chemistry, hydrate inhibition, asphaltene remediation, hydrate remediation, calcium, production chemistry, soluble calcium, colombia, field application Subjects: Production Chemistry, Metallurgy and Biology, Inhibition and remediation of hydrates, scale, paraffin / wax and asphaltene This content is only available via PDF. 2009. Offshore Technology Conference You can access this article if you purchase or spend a download.