Barium Sulphate Formation Kinetics and Inhibition at Surfaces

This study refers to experimental work and analysis of the barium sulphate deposition onto surfaces. In the oil field the formation of barium sulphate is a major flow assurance issue. The build up of the BaS04 inorganic scale on surfaces and facilities is undesirable as it causes increased function, reduction in production and other flow assurance issues. To date the overwhelming amount of research has been on the bulk precipitation of barite and little attention has been paid to deposition onto surfaces. This study shows an integrated approach to access the formation kinetics of barite at surfaces. Both the formation kinetics and the crystallography of the deposited barite are explored under examined conditions intended to imitate in some part the off-shore environment. In addition the effect of chemical additives performing as inhibitors of the barite growth is kept as a main concern of this study. Understanding the behavior of the inhibitors and their retardation mechanisms can further target the improvement of inhibition and overall antiscaling techniques. The thesis work has demonstrated that the surface growth kinetics of barite is largely different to bulk kinetics and interesting phenomena occur at surfaces especially when inhibitors are used. There are complex interactions of the inhibitor with the scale and both growth kinetics and crystal morphology are affected with threshold concentrations. The input of the inhibition mechanisms is discussed.