ВЫБОР МЕТОДИКИ УЛАВЛИВАНИЯ И ЗАКАЧКИ CO2 ДЛЯ ПОВЫШЕНИЯ НЕФТЕОТДАЧИ ПРИРАЗЛОМНОГО МЕСТОРОЖДЕНИЯ

This article presents the results of a study into the selection of the optimal technology for capturing carbon dioxide (CO₂) generated during the combustion of associated petroleum gas at flare plants, using the Prirazlomnoyefield in the West Siberian oil and gas province as a case study. The paper examines options for the subsequent use of the captured gas to enhance oil recovery from the reservoir, using the BS4-5 productive horizon as an example. The relevance of this work stems both from environmental requirements to reduce greenhouse gas emissions from flaring and from the economic viability of reusing CO₂ in field development systems. The study examines and compares three CO₂ capture technologies: amine absorption, oxygen-enriched combustion and membrane separation of gas mixtures. For each method, the technical and economic characteristics, energy consumption, degree of gas purification, equipment requirements and applicability under the conditions of the operating field have been analysed. Based on the results of the comparative analysis, the choice of amine absorption is justified as the most effective and technologically feasible solution for the conditions of the field under consideration. To assess the effectiveness of using captured CO₂ to enhance oil recovery, a hydrodynamic model of the BS4-5 reservoir was constructed in the tNavigator software suite, taking into account the geological and physical characteristics of the reservoir and the field’s development history. A comparison of scenarios involving gas and water-gas stimulation of the reservoir showed that the water-gas method using CO₂ provides a greater increase in the oil recovery factor compared with gas-only stimulation, and also contributes to a more uniform displacement of oil along the reservoir section and a reduction in gas breakthroughs to production wells. Water-gas flooding enables an increase in the oil recovery factor of 12.96 per cent compared with gas flooding. Based on the results obtained, practical recommendations have been formulated for the implementation of CO₂ capture and injection technology into the field’s production cycle. The conclusions drawn can be used in the design of similar systems at other fields with comparable geological and engineering conditions.