Remediation of aphaltene and other heavy organic deposits in oil wells and in pipelines

Abstract

ReseRvoiR and petRoleum engineeRing ELMİ ƏSƏRLƏR w PROCEEDINGS w НАУЧНЫЕ ТРУДЫ 12 INTRODUCTIONarterial blockage in the petroleum industry is mostly due to the deposition of heavy organic molecules from petroleum fluids. Heavy organic molecules such as asphaltenes, asphaltogenic acids, diamondoids and derivatives, mercaptans, organometallics, paraffin /wax and resins exist in crude oils ( fig.1) in various quantities and forms [1,2]. such compounds could separate out of the crude oil solution due to various mechanisms and deposit, causing fouling in the oil reservoir, in the well, in the pipelines and in the oil production and processing facilities [1][2][3][4][5][6]. solid particles suspended in the crude oil may stick to the walls of the conduits and reservoirs ( fig.2). the toughness of the deposits has a lot to do whether there is asphaltene present in the crude oil even in minute quantities.asphaltene, which is a highly polar compound, generally act as a glue and mortar in hardening the deposits and, as a result, causing barrier to the flow of oil [7][8][9][10][11][12][13][14].depositions of the heavy organics present in crude oil happen due to various causes depending on their molecular nature. mercaptans and organometallics depositions are due to dissociation, solubility effects, or attachment to surfaces. diamondoids and paraffin/wax deposit and form solid crystals due, mostly, to lowering of temperature [15][16][17]. Resins are not known to deposit on their own, but they deposit together with asphaltenes [18]. the reasons for the asphaltenes and asphaltogenic acids deposition can be many factors including variations of temperature, pressure, pH, composition, flow regime, wall effect and electrokinetic phenomena. When several different heavy organic compounds are present in a in this report the methodologies and analysis for in situ remediation of heavy organics in petroleum production, transportation and processing industries is presented. First the heavy organics which deposit from petroleum fluids are indentified and it is pointed out that the more difficult member of these compounds to deal with are asphaltenes. six different in situ remediation methods are introduced which include: (i) production scheme alteration techniques; (ii) chemical treatment techniques; (iii) external force filed techniques; (iv) mechanical treatment techniques; (v) thermal treatment techniques; (vi) biological methods. also eight steps that appear to be necessary and effective in prevention and moderating the severity of the deposition and remediation are introduced which include: (a) predictive modeling and analysis; (b) dual completion of oil wells; (c) compatibility tests of injection fluids before applications; (d) consideration of the compositional gradient of heavy organics in reservoir in production scheme design; (e) application of mechanical removal technologies for deposits; (f) application of solvent for dissolution of deposits; (g) hot oil treatment of the in situ deposits; and (h) use of dispersant to stabilize ...

Experimental Investigation of Asphaltene Content Effect on Crude Oil/CO2 Minimum Miscibility Pressure

“…As a result, by determining gas and oil IFT as a function of composition and pressure, and extrapolating the functions to the point at which the IFT is zero, the Minimum Miscibility Pressure (MMP) and Minimum Miscibility Composition (MMC) can be measured, correspondingly. In this respect, the VIT method can be adopted to calculate the gas/oil IFT using the pendant drop technique which is conducted by ADSA software by the Young Laplace equation at different temperatures and pressures of the reservoir [6,7,25].…”

“…In particular, while the CO 2 injection process is performed, the phenomenon of asphaltene precipitation is one of the most challenging issues which should necessarily be addressed. This phenomenon causes many problems such as pore blockage and wettability alteration within reservoir porous media and unfavorably affects the sweep efficiency [5][6][7][8]. Hence, measuring the effects of asphaltene content over the MMP is of paramount importance in CO 2 / oil systems, specifically at high temperatures and pressures [9][10][11].…”

Review of Asphaltenes in an Electric Field

“…To deal with asphaltene deposition problems, two main categories of techniques have been applied: inhibition and treatment. The use of chemical inhibitors and manipulation of oil production conditions incorporate inhibition techniques, while the treatment methods comprise mechanical, thermal, chemical, biological, and electrical approaches. − Most of these techniques are extremely costly. One example of a possible inhibition technique is the addition of dispersants in order to change the net charge of the asphaltene aggregates, making them more dispersible in the oil mixture. , However, in the case of heavy oil with a high asphaltene content, this method is inefficient and costly .…”

Mechanism of an asphaltene inhibitor in different depositing environments: Influence of colloid stability

“…Solvent cleaning (e.g. with xylene or other aromatics) is used to dissolve deposits (Elochukwu and Mahmud, 2015;Mansoori, 2010). Additives (e.g.…”