CO<2> geological storage method and CO<2> geological storage system

Abstract

The invention discloses a CO<2> geological storage method and a CO<2> geological storage system. The method comprises the following steps that a CO<2> reservoir stratum and a cover layer are determined according to a geological environment; a CO<2> injection well and a salt water extraction well are excavated, and the CO<2> injection well and the salt water production well both communicate with the CO<2> reservoir stratum; CO<2> is injected into the CO<2> reservoir stratum through the CO<2> injection well, meanwhile, salt water in the CO<2> reservoir stratum is extracted through the salt water extraction well, the pressure of the CO<2> reservoir stratum is reduced, and the pore available space of the CO<2> reservoir stratum is increased; and the CO<2> is stored in the CO<2> reservoir stratum in a sealed mode; According to the method, the salt water extraction well is excavated while the CO<2> injection well is excavated, CO<2> is injected into the CO<2> reservoir stratum through the CO<2> injection well, and meanwhile salt water in the CO<2> reservoir stratum is extracted through the salt water extraction well, so that the pressure of the CO<2> reservoir stratum is reduced and the pore available space of the CO<2> reservoir stratum is increased, and therefore the storage coefficient of the CO<2> reservoir stratum can be remarkably increased, and then the total storage amount of the CO<2> reservoir stratum is increased, namely, the sealing capacity of the CO<2> reservoir stratum is improved.

Description

technical field [0001] The invention relates to the technical field of carbon dioxide sequestration, in particular to a CO 2 Geological storage methods and systems thereof. Background technique [0002] In recent years, due to carbon dioxide (CO 2 ) and other greenhouse gas emissions have caused global warming to become increasingly significant, resulting in a series of serious consequences such as frequent extreme weather and rising sea levels. Therefore, greenhouse gas emission reduction has become one of the hot issues in the international community today. CO 2 As an emerging technology that can effectively reduce carbon emissions and realize low-carbon development of the global economy, capture, geological use and storage (CCUS) has attracted great attention from the international community. China's current CO 2 Emissions rank first in the world, about 80% of which come from concentrated emission sources such as power plants and cement plants, and CCUS technology is...

AI Technical Summary

Problems solved by technology

[0006] The Chinese patent application publication No. CN 106904616 A discloses a carbon dioxide geological storage structure and storage method, using well area equipment in oil and gas exploitation to inject carbon dioxide to 300-500 meters underground, which greatly reduces the cost of storage. However, on the one hand, due to The depth has not reached the ideal depth, and carbon dioxide may not necessarily reach supercritical CO 2 Density, ultimately not necessarily able to increase the CO 2 In addition, the well area in oil and gas exploitation has not changed the formation environment, and there is still a problem of low storage coefficient

[0007] In addition, the Chinese patent application publication number CN 102425870 A discloses a method to improve geothermal recharge rate and CO 2 The integrated method of geological storage, the Chinese patent application publication number CN 103603639 A discloses a system for mining and heat utilization of high-salt brine in deep formations. Both of the above two schemes adopt the method of injecting CO 2 To maintain a constant pressure in the geothermal reservoir and improve the extraction efficiency of brine and geothermal resources. 2 Total Storage

Images