Effect of wettability on particle settlement behavior within Mono-Ethylene Glycol regeneration pre-treatment systems
Abstract
This study was undertaken to diagnose routine settling problems within a third-party oil and gas companies’ Mono-Ethylene Glycol (MEG) regeneration system. Two primary issues were identified including; a) low particle size (<40 >μm) resulting in poor settlement within high viscosity MEG solution and b) exposure to hydrocarbon condensate causing modification of particle surface properties through oil-wetting of the particle surface. Analysis of oil-wetted quartz and iron carbonate (FeCO₃) settlement behavior found a greater tendency to remain suspended in the solution and be removed in the rich MEG effluent stream or to strongly float and accumulate at the liquid-vapor interface in comparison to naturally water-wetted particles.
As such, exposure of particles including quartz and FeCO₃ to the condensate phase within natural gas transportation pipelines may ultimately cause poor settlement of suspended particles downstream within MEG regeneration systems, leading to increase filtration requirements. The effect of oil-wetting on particle settlement was successfully managed through application of a cationic surfactants, including cetrimonium bromide (CTAB), to transition the initially oil-wetted surface to water-wetted. Cationic surfactants were found to be most suitable due to the negative surface charge of mineral particles at pH levels typical of MEG regeneration system pre-treatment systems (pH > 8).
Keywords
MEG, Mono-ethylene glycol, Particle settlement, Wettability
Document Type
Journal Article
Date of Publication
2019
Publication Title
Journal of Petroleum Science and Engineering
Publisher
Elsevier BV
School
School of Engineering
RAS ID
30202
Copyright
subscription content
Comments
Soames, A., Al-Anssari, S., Iglauer, S., Barifcani, A., & Gubner, R. (2019). Effect of wettability on particle settlement behavior within Mono-Ethylene Glycol regeneration pre-treatment systems. Journal of Petroleum Science and Engineering, 179, 831-840. Available here