Demulsifier Performance and Dehydration Mechanisms in Colombian Heavy Crude Oil Emulsions

Abstract

Important differences arise when chemical demulsification strategies are implemented for heavy crude oils (°API ∼ 10). Traditional methods for screening and selecting an appropriate demulsifier based on bottle tests and lipophilic–hydrophilic parameters (i.e., HLB, RSN, and so on) tend to be less adequate because of the almost negligible density difference between the oil and the water phases. This situation leads to a detriment of the separated water often mixed with undesired dense-packed layers (DPLs) and emulsion layers. In this work, dehydration of heavy crude oil emulsions from a Colombian oilfield was assessed through the use of a wide range of chemical demulsifiers of different functionalities. Through the use of bottle tests and transmission/backscattering measurements, it was shown that the demulsification mechanisms involved in these limiting cases (low density difference) are different. Hence demulsifiers with functional groups that have traditionally performed very well for lighter oils fail when applied to the heavy crude oil cases. Poly­(ethylene oxide)/poly­(propylene oxide) block copolymer-based products (PEO/PPO) do not seem to have the ability to penetrate the asphaltene network/film at the liquid–liquid interface (separated water, <17%) while the alkylphenol-aldehyde resins seem to prevent the formation of DPLs/emulsion layers possibly through polar interactions, yielding a good quality water phase after separation.

Novel Bionanocompounds: Outer Membrane Protein A and Laccase Co-Immobilized on Magnetite Nanoparticles for Produced Water Treatment

“…With the increase in the popularity of nanomaterials, the past two decades have seen their incursion in this industry in an attempt to enhance the efficiencies of numerous conventional processes [ 58 , 87 , 88 , 89 ]. For instance, different types of nanomaterials have been implemented for the treatment and recovery of emulsified effluents with moderate efficiencies [ 77 , 90 ]. In parallel, alternative remediation processes such as those based on biosurfactants have gained attention due to the possibility of operating at milder conditions [ 91 , 92 ].…”

Demulsification of Colombian Heavy Crude Oil (W/O) Emulsions: Insights into the Instability Mechanisms, Chemical Structure, and Performance of Different Commercial Demulsifiers

“…Further description and details of this procedure can be found elsewhere. 29 Traditional bottle tests were used in this work to assess the performance of the demulsifiers under similar conditions to those typically found in oilfield evaluations. 35 Once the emulsion was prepared (see the previous section for details), the required amount of demulsifier solution was pipetted at a concentration of 2500 ppm.…”

Screening and Demulsification Mechanism of Fluorinated Demulsifier Based on Molecular Dynamics Simulation

“…Transportation and refining of this stable emulsion without treatment can cause serious problems, such as pipeline corrosion, scaling, increased equipment load and fuel consumption [ 7 , 8 ]. Conventional demulsification technology mainly includes physical demulsification, chemical demulsification and biological demulsification [ 9 , 10 , 11 ]. Chemical demulsification requires simpler equipment and has a lower cost and better demulsification effect.…”