Heavy-Oil Dilution

Abstract

Heavy Oil Dilution J-Francois Argillier; J-Francois Argillier Institut Français du Petrole Search for other works by this author on: This Site Google Scholar Isabelle Henaut; Isabelle Henaut Institut Français du Petrole Search for other works by this author on: This Site Google Scholar patrick gateau; patrick gateau IFP Search for other works by this author on: This Site Google Scholar Jean-Philippe Heraud; Jean-Philippe Heraud IFP Search for other works by this author on: This Site Google Scholar Philippe Glenat Philippe Glenat Total S.A. Search for other works by this author on: This Site Google Scholar Paper presented at the SPE International Thermal Operations and Heavy Oil Symposium, Calgary, Alberta, Canada, November 2005. Paper Number: SPE-97763-MS https://doi.org/10.2118/97763-MS Published: November 01 2005 Cite View This Citation Add to Citation Manager Share Icon Share Twitter LinkedIn Get Permissions Search Site Citation Argillier, J-Francois, Henaut, Isabelle, gateau, patrick, Heraud, Jean-Philippe, and Philippe Glenat. "Heavy Oil Dilution." Paper presented at the SPE International Thermal Operations and Heavy Oil Symposium, Calgary, Alberta, Canada, November 2005. doi: https://doi.org/10.2118/97763-MS Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAll ProceedingsSociety of Petroleum Engineers (SPE)SPE International Thermal Operations and Heavy Oil Symposium Search Advanced Search AbstractHeavy or extra heavy crude oils cannot be transported by pipeline without a prior reduction of their viscosity. This is commonly obtained by blending the oil with light hydrocarbons. In that case, the resulting viscosity of the mixture depends only on the dilution rate, and on the respective viscosities and densities of the oil and of the diluent. Classical diluent are light crudes, condensates, naphtha. Availability of the diluent and its possible recycling needs of course to be taken in account. In this work we have studied the influence of composition of the diluent on the viscosity reduction efficiency. In particular we show that the addition of a polar solvent to a solution of asphaltenes in toluene acts on the colloidal structure of the asphaltenes. The relative viscosity of the solution decreases, as well as the size of the aggregates of asphaltenes. In the same way, by mixing hydrocarbons and solvents owning polar functional groups in their molecule, it is shown that the efficiency of the dilution of heavy crude oils is enhanced. Hansen's theory can be used to screen the solvent efficiency. At constant dilution rate, the higher the polarity parameter or the hydrogen bonding parameter of the solvent, the greater the relative viscosity reduction of the diluted crude oil. Nevertheless, solvent owning high hydrogen bonding are generally more viscous than hydrocarbons. The influence of their interactions with the asphaltenes is hidden when the results are expressed in absolute viscosity. Polar solvents giving few hydrogen bonding give a significant reduction of the viscosity of the diluted crude oil. From an economical point of view, any improvement of the efficiency of the thinner could be a benefit for the process, by reducing the amount of solvent needed to get an acceptable viscosity, and therefore allowing a greater quantity of crude to be transported.IntroductionThe increasing oil demand and advances in heavy oil production technologies is leading to the increased production of this type of hydrocarbon. The reserves in Alberta, Canada represent a potential resource of 1.7 billion barrels of oil and a further 1.3 billion are considered to exist in the orinico belt fields, Venezuela. The API gravity of these oils is extremely low Athabascan heavy oil has an API gravity of between 8°-10° API and Orinico Belt heavy oil has an API gravity of 10°-12°. These high densities lead to correspondingly high viscosities in the Athabascan case over 1,000,000 centiPoise and between 1,500 and 3,000 for Venezuelan heavy oils at reservoir temperatures. These physical properties make heavy oil difficult to produce, separate and then transport. Most pipeline systems require the dehydrated crude to have an API gravity specification of 19°API (400 cP viscosity).Although potential alternatives exist (Partial Upgrading on site, Oil in water emulsion, Core Annular Flow) this specification is in most cases obtained by dilution with a lighter hydrocarbon additive. Condensates have been used until the end of the 80's to transport almost the whole production of the Canadian crude [1, 2]. Another choice to dilute heavy oils is to use of a light crude, with an API gravity range from 35 to 42 [2, 3]. Light oils are less efficient in reducing the viscosity of heavy oils than condensates and they are subjected to the same limitations of availability and of compatibility with asphaltenes. Naphtha seems to be an interesting alternative to the use of condensates [1]. Because its high API gravity, it is very efficient in diluting heavy oils. Naphthas show a good compatibility with asphaltenes and are easily recycled. Dilution with naphtha associated with solvent recycling has been used in Canada and in Venezuela.This study aims at showing that the polarity of the thinner has some influence of the viscosity reduction of the solution. Some of the results presented here have been described elsewhere [4]. Keywords: asphaltene remediation, upstream oil & gas, interaction, mek, remediation of hydrates, viscosity, complex reservoir, scale remediation, heavy oil, flowrate Subjects: Production Chemistry, Metallurgy and Biology, Unconventional and Complex Reservoirs, Inhibition and remediation of hydrates, scale, paraffin / wax and asphaltene, Oil sand, oil shale, bitumen This content is only available via PDF. 2005. SPE/PS-CIM/CHOA International Thermal Operations and Heavy Oil Symposium You can access this article if you purchase or spend a download.