Global warming has slowly threatened the rapid development of mankind which makes CO2 as the main greenhouse gas utilization research has attracted more and more attention owing to its excellent energy increasing effect, especially, it provides new ideas for the development of marine heavy oil resources. The steam injection effect of offshore heavy oil reservoirs with strong edge water is restricted by problems such as short oil production time and fast edge water coning speed, CO2 assisted steam stimulation technology will effectively improve the production during steam injection in offshore heavy oil reservoirs with edge water.
The paper established a CO2 assisted cyclic steam stimulation model for offshore strong edge water heavy oil reservoir based on the rock hydrothermal reaction under CO2. Here the geochemical and fluid flow aspects are fully coupled such that the time dependent CO2 rock hydrothermal reaction is strictly preserved. Secondly, the transformation from immovable sand to mobilized sand under specific conditions is described, and the sand migration mechanism varying with time is revealed, acquired the storage mechanism and influencing factors of CO2 under steam injection. In addition, the edge water reservoir model with water rock reaction is established by CMG, which are benefited to optimizing injection production parameters of controlling water coning and increasing CO2 storage in offshore edge water heavy oil reservoir
It can analyze the edge water coning characteristics under the condition of time-varying porosity and permeability, as well as the expansion of steam chamber in the steam development process of edge water heavy oil reservoir, and the analysis of CO2 concentration distribution, to improve the utilization rate of steam energy and reduce energy consumption. Besides it provides theoretical support for the development of offshore strong edge water heavy oil reservoir and realizes the integration of carbon storage and crude oil production.
Keywords Interdisciplinary qualification, sustainable energy and structural transformation, decarbonization, coal phase-out, closed carbon cycle