Investigation of the Model Paraffin Systems for Development of Thermal Insulation of Pipelines in Permafrost Zone

Abstract

The potential of using paraffin deposits as natural insulation of the internal surface of oil pipelines in the permafrost zone has been considered. Paraffin deposits have been collected from the surface of oil field equipment in the Irelyakhskoye gas and oil field (Sakha Republic (Yakutia). The method of differential scanning calorimetry has been applied for study of phase transformation of commercial paraffins in the composite solvents based on gas condensate (GC) that is currently used for removal of paraffin deposits in this field, and in the composite solvents based on n-undecane (n-C11), as a model of the gasoline fraction of condensate. Binary and ternary composites based on gas condensate andn-undecane represent compositions with cyclohexane andp-xylene. The degree of crystallinity (DC) of paraffins has been determined to depend on the degree of aliphaticity of used composite solvents – as the degree of aliphaticity of solvents increases, DC of paraffins decreases. It has been identified that paraffins in ternary solvents based on GC and onn-C11 have low DC and high melting points. The results of research allow us to recommend paraffin deposits in ternary solvents obtained from GC as a promising raw material for thermal insulation of pipelines through targeted paraffinization, thus reducing a heat loss to the surroundings from oil and avoiding soil thawing and destruction in the permafrost area.