GREENHOUSE GASES DISPOSAL IN GEOLOGICAL TRAPS FOR OIL AND GAS STIMULATION

Abstract

Background The emission of technogenic greenhouse gases is closely related to the negative climate change on Earth. In this regard, the international community has recognized the need for coordinated measures to reduce emissions of all greenhouse gases, including CO2, into the atmosphere, establishing laws at the state level to protect the environment. Only significant changes in traditional power engineering, the transition to regenerative energy sources, and sequestration of technogenic CO2 will slow down growth and then completely reduce greenhouse gas emissions. One of the promising areas for Russia is the disposal of oil reservoirs and hydrate formations in greenhouse gas. There are no reserves of natural carbon dioxide in Russia, however, the reserves of greenhouse gases (flue gases and CO2) have unlimited resources and can be used for the extraction of hydrocarbons. CO2 sequestration for the production of hard-to-recover reserves (TRIZ) of oil can be more effective than traditional waterflooding due to increased oil recovery of depleted fields of low and medium viscosity oil. The main disadvantage of sequestration is the high investment cost. It is almost impossible to start a sequestration project without creating a plant for capturing, concentrating and dehydrating CO2, transport infrastructure and a fully equipped trap. There are also problems of increasing the capacity of water layers and increasing the safety of storing greenhouse gases in them. Thus, solving the problems of technological improvement and reducing the cost of greenhouse gas disposal is an urgent task. Aims and Objectives Development of scientific foundations of the process of greenhouse gases sequestration in geological traps for oil and gas stimulation, as well as increasing the capacity of geological traps and the reliability of the sequestrate storage. Results The processes of CO2 sequestration in a deep-lying aquifer, the influence of the injection of carbon dioxide water and the direction of the displacement front on the change in the volume of the geological trap are considered. Research on sequestration of greenhouse gases in Devonian reservoirs using flue gas and technogenic CO2 for oil production has been carried out. The oil-displacing and filtration characteristics of water-gas mixtures (WGM) containing greenhouse gases have been investigated. The dynamics of filtration when displacing the residual oil of the WGM from the enriched flue gas is indicated, and the optimal content of CO2 in the WGM for injection into injection wells with reduced injectivity is revealed.