Discussion of Agglomeration Mechanisms between Hydrate Particles in Water in Oil Emulsions

Abstract

Line blockage due to gas hydrate formation in water/oil emulsions can be understood by considering the increase in the effective volume fraction ϕeff of dispersed particles in the hydrate slurry. This increase is the result of an agglomeration process that takes place during hydrate formation. Two mechanisms of agglomeration reported in the literature are discussed. The first one is the contact-induced agglomeration mechanism for which the crystallization-agglomeration process is described as the result of the contact between a water droplet and a hydrate particle. The second one is the shear-limited agglomeration mechanism for which the balance between hydrodynamic force and adhesive force is considered. It is proposed to gather these two mechanisms in a unified model in order to predict the evolution of the viscosity of the slurry during hydrate formation. Such a model can be based on a Population Balance Model in which the agglomeration kernel is related to the contact-induced mechanism and the fragmentation kernel is related to the shear-limited mechanism.