In Situ Upgrading Heavy Oil by Aquathermolytic Treatment under Steam Injection Conditions

Abstract

In Situ Upgrading Heavy Oil by Aquathermolytic Treatment under Steam Injection Conditions S. Jiang; S. Jiang Liaohe Oilfield Search for other works by this author on: This Site Google Scholar X. Liu; X. Liu Liaohe Oilfield Search for other works by this author on: This Site Google Scholar Y. Liu; Y. Liu Daqing Petroleum Institute Search for other works by this author on: This Site Google Scholar L. Zhong L. Zhong Daqing Petroleum Institute Search for other works by this author on: This Site Google Scholar Paper presented at the SPE International Symposium on Oilfield Chemistry, The Woodlands, Texas, February 2005. Paper Number: SPE-91973-MS https://doi.org/10.2118/91973-MS Published: February 02 2005 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Jiang, S., Liu, X., Liu, Y., and L. Zhong. "In Situ Upgrading Heavy Oil by Aquathermolytic Treatment under Steam Injection Conditions." Paper presented at the SPE International Symposium on Oilfield Chemistry, The Woodlands, Texas, February 2005. doi: https://doi.org/10.2118/91973-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 ProceedingsSociety of Petroleum Engineers (SPE)SPE International Conference on Oilfield Chemistry Search Advanced Search AbstractAquathermolytic technology that involves upgrading heavy oil using chemical additives is introduced in this paper. Laboratory experiments were carried out under steam injection conditions to investigate catalysis of some metal species and synergetic effect of catalyst and hydrogen donor on aquathermolysis of Liaohe and Shengli heavy oils. As a result, significant reduction in viscosity and contents of asphaltene and resin was obtained, thus heavy oils were upgraded greatly. Then the mechanism of aquahtermolysis is discussed further. Additionally, the field test in Liaohe Oifield is introduced. The future is suggested in the end.IntroductionAs an unreproducible fossil energy, petroleum is the most important energy and materials in the world. However, oil crisis is coming in the industrial countries, even the developing countries such as China because of declining production of conventional oil and increasing demand for energy. So importance has to be attached to heavy oil production.At the same time, it is very difficult to recover and transport heavy oil because of its high viscosity that derives from special molecular structures and large contents of heavy components, mainly asphaltente and resin. Most of heavy oil is produced by thermal recovery technologies such as steam injection which could heat heavy oil and reduce its viscosity in situ temporarily. Other technologies such as emulsification could assist thermal production. Nevertheless, there are no radical changes in molecular structures or components of heavy oil.However, aquathermolytic technology introduced in this paper could upgrade heavy oil in situ by adding catalyst and other additives under aqueous and thermal conditions. As a result, contents of heavy components are decreased, or molecular structures transformed, consequently, viscosity reduced. Aquathermolytic technology is a potential catalytic visbreaking process for heavy oil recovery, and it could enhance heavy oil recovery of steam injection and other thermal recovery processes[1–3].Actually, both field evidences and laboratory experiments indicate that there are some chemical reactions designated aquathermolysis occurring between heavy oil and water under steam injection and other thermal recovery conditions, which could lead to chemical reduction in heavy oil viscosity[4, 5].Research on aquathermolysis of heavy oil under steam injections has been carried out in recent three decade by Hyne, Clark et al[3–6]. The result indicates significant reduction in viscosity and contents of asphaltene and resin, increase in saturated and aromatic hydrocarbons, and generation of some gases such as carbon oxide, hydrogen, methane, and so on. Some transition metal species were also introduced as catalysts to accelerate aquathermolysis. The results of aquathermolysis of Liaohe heavy oil were also reported by Liu, Fan et al[7–11]. It is suggested that heavy oils appear to undergo competitive chemical transformations which affect viscosity in opposite ways during aquathermolysis. Once reactive fragments have been generated by cleavage of sensitive structures such as the C-S bonds in aquathermolysis, either they can polymerize and thus raise viscosity of heavy oil, or initiate a series of further reactions that result in generation of products which can reduce viscosity even in relatively small amounts. Hydrogen donors are potential to prevent reactive fragments or radicals from polymerizing under steam injection conditions according to the work by Ovalles, Vallejos, et al[12].In this work, using typical Liaohe and Shengli heavy oil, laboratory experiments were carried out with addition of catalyst and/or hydrogen donor at different temperature and reaction time. The oils are analyzed in terms of viscosity, element, hydrocarbon components and SARA, then catalysis of metal species and synergetic effect of catalyst and hydrogen donor on aquathermolysis are investigated. Based on this work, the mechanism of heavy oil aquathermolysis is discussed further. Additionally, the field test carried out at twenty wells in Liaohe Oilfield is introduced. The future is suggested in the end.Laboratory ExperimentsMaterials, equipment and processesThe heavy oils used were sampled from Shuguang region in Liaohe Oilfield and East Shan 6 region in Shengli Oilfield. Keywords: catalyst, aquathermolytic treatment, shengli heavy oil, hydrogen donor, heavy oil, metal species, reaction time, spe 91973, viscosity, sagd Subjects: Processing Systems and Design, Improved and Enhanced Recovery, Unconventional and Complex Reservoirs, Heavy oil upgrading, Thermal methods, Oil sand, oil shale, bitumen This content is only available via PDF. 2005. 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