WAX PRECIPITATION PREDICTIVE MODEL MODIFICATION ON THE EXAMPLE OF A KAZAKHSTAN OIL

Currently, the oil and gas segment of Kazakhstan is facing such a problem as paraffin deposits. The problem associated with the deposition and crystallization of paraffin causes large-scale difficulties, and models for predicting wax precipitation are limited to specific types of oil, and therefore there is a need to improve them. The authors of this article analyzed and developed a predictive model of paraffin deposition from crude oil for Kazakhstani fields. The work is based on the study of Lira-Galeana et al., which considers the multicomponent deposition of immiscible solids from an oil mixture - a multi-solid model. During the study, it was found out that the Lira-Galeana model uses the equation of state, the volatility properties of the components and the activity coefficient. The Poynting effect was considered at high pressures in the system. For experimental studies, oil samples were taken from two fields. The component composition of the oil, the pour point and loss of fluidity of the oil, as well as the melting point temperatures were determined in laboratory conditions. The amount of paraffin sludge from the oil was estimated experimentally. The results obtained are fully consistent with the analytical solution. During laboratory tests, it was found that the oil from the second field was heavier, and the degree of crystallization of paraffin was more significant than that of oil from the first field under the same conditions. Using this predictive model, the authors were able to predict the amount of solid precipitation from crude oil during the year, depending on changes in ambient temperature.