Analytical Instrumentation

Transferring interfacial rheology data from lab tests to practical midstream processing: Optimizing demulsifier performance to reduce corrosion and pipeline pressure peaks

Feb 08 2016

Author: Dr Robert Minch on behalf of Kruss GmbH

Free to read

This article has been unlocked and is ready to read.

Download

During the process of oil recovery, water-in-oil (w/o)-emulsions are formed due to the presence of surface active substances, being natural components of the oil or being part of flooding mixtures, e. g. in enhanced oil recovery (EOR). The formation of such emulsions alters the oil's viscosity, creating pressure peaks in midstream processing that eventually damage technical equipment like pumps. Additionally, w/o-emulsions contain an elevated amount of salty water, which promotes material corrosion in petroleum refining. To avoid these technical problems, so-called demulsifiers are in use that break up w/o-emulsions and result in a decreased viscosity and water content of crude oil. As parameters like water and oil composition differ in between reservoirs, demulsifiers have to be selected carefully and on an individual level.

Different demulsifier systems were investigated on a lab scale by means of interfacial rheology measurements, using the oscillating drop method. Different concentrations of mixtures of asphaltenes in toluene were characterized. It was found that the change in storage modulus (E') of the asphaltene-water interface upon addition of demulsifying agents strictly correlated with the stability of w/o emulsions. Based on these lab results, the most promising demulsifier system was identified. The real perfomance of this system was then tested in field for practical midstream processing and results were compared to a commercially available standard demulsifier. It was shown that deviations in pumping pressure could be reduced from 11.5 ± 2 atm to 11.0 ± 0.5 atm after switching from the standard demulsifier to the system that was designed according to interfacial rheology lab tests. In addition, the water as well as the salt content could be reduced significantly for three different crude oil samples. These results clearly show how interfacial rheology measurements on a lab scale can be transferred to petroleum midstream processing to optimize the performance of demulsifying agents and eventually prevent pressure peaks and corrosion.


Digital Edition

PIN Buyers Guide 24.6

January 2024

In This Edition Product Listings & Exhibition Diary - A-Z of Products and Services - A-Z of Company Contact Details Safety Articles - The technology behind the ION Science Tiger XT -...

View all digital editions

Events

International Energy Week

Feb 27 2024 London. UK

OTC ASIA 2024

Feb 27 2024 Kuala Lumpur, Malaysia

Nepal Lab

Feb 29 2024 Kathmandu, Nepal

IFPAC 2024

Mar 03 2024 Bethesda, MA, USA

ChemTech World Expo 2024

Mar 04 2024 Mumbai, India

View all events