The paper presents an analysis of the possible location of geological formations suitable for CO₂ storage in the Upper Silesia Coal Basin, Poland. The range of the reservoir has been determined on the basis of an analysis of basic geological parameters, which determine the selection criteria for sites suitable for CO₂ storage. A dynamic modelling of the CO₂ distribution in the aquifer is presented. Based on the constructed model of migration, reactivity, and geochemical transport of CO₂ in geological structures, it is possible to identify potential migration routes and escape sites of CO₂ on the surface. The analysis of the technical and geological possibilities of CO₂ storage was carried out according to the regulations of the complex Polish geological law, specifically in terms of sequestration possibilities in geological formations.

The paper presents a research study on modeling and computer simulation of injecting CO₂ into the coal seams of the Upper Silesian Coal Basin, Poland connected with enhanced coal bed methane (ECBM) recovery. In the initial stage of the research activities, a structural parameter model was developed specifically with reference to the coal-bearing formations of the Upper Carboniferous for which basic parameters of coal quality and the distribution of methane content were estimated. In addition, a lithological model of the overall reservoir structure was developed and the reservoir parameters of the storage site were analyzed. In the next stage of the research, the static model was supplemented with detailed reservoir parameters as well as the thermodynamic properties of fluids and complex gases. The paper discusses a series of simulations of an enhanced coalbed methane recovery process with a simultaneous injection of carbon dioxide. The analyses were performed using the ECLIPSE software designed for simulating coal seam processes. The results of the simulations demonstrated that the total volume of CO₂ injected to a designated seam in a coal mine during the period of one year equaled 1,954,213 sm³. The total amount of water obtained from the production wells during the whole period of the simulations (6.5 years) was 9867 sm³. At the same time, 15,558,906 sm³ of gas was recovered, out of which 14,445,424 sm³ was methane. The remaining 7% of the extracted gas was carbon dioxide as a result of reverse production of the previously injected CO₂. However, taking into consideration the phenomena of coal matrix shrinking and swelling, the total amount of injected CO₂ decreased to approximately 625,000 sm³.

Deep un-mineable coal deposits are viable reservoirs for permanent and safe storage of carbon dioxide (CO₂) due to their ability to adsorb large amounts of CO₂ in the microporous coal structure. A reduced amount of CO₂ released into the atmosphere contributes in turn to the mitigation of climate change. However, there are a number of geomechanical risks associated with the commercial-scale storage of CO₂, such as potential fault or fracture reactivation, microseismic events, cap rock integrity or ground surface uplift. The present study assesses potential site-specific hydromechanical impacts for a coal deposit of the Upper Silesian Coal Basin by means of numerical simulations. For that purpose, a near-field model is developed to simulate the injection and migration of CO₂, as well as the coal-CO₂ interactions in the vicinity of horizontal wells along with the corresponding changes in permeability and stresses. The resulting effective stress changes are then integrated as boundary condition into a far-field numerical model to study the geomechanical response at site-scale. An extensive scenario analysis is carried out, consisting of 52 simulation runs, whereby the impacts of injection pressures, well arrangement within two target coal seams as well as the effect of different geological uncertainties (e.g., regional stress regime and rock properties) is examined for operational and post-operational scenarios. The injection-induced vertical displacements amount in maximum to 3.59 cm and 1.07 cm directly above the coal seam and at the ground surface, respectively. The results further demonstrate that neither fault slip nor dilation, as a potential consequence of slip, are to be expected during the investigated scenarios. Nevertheless, even if fault integrity is not compromised, dilation tendencies indicate that faults may be hydraulically conductive and could represent local pathways for upward fluid migration. Therefore, the site-specific stress regime has to be determined as accurately as possible by in-situ stress measurements, and also fault properties need to be accounted for an extensive risk assessment. The present study obtained a quantitative understanding of the geomechanical processes taking place at the operational and post-operational states, supporting the assessment and mitigation of environmental risks associated with CO${}_2$ storage in coal seams.

The paper presents the assessment of the resources of methane considered as the main mineral in the most prospective selected areas of the Upper Silesian Coal Basin, Poland in the region of undeveloped deposits. The methane resources were estimated by means of a volumetric method at three depth levels, 1000, 1250, and 1500 m. A part of the Studzienice deposit comprising three coal seams, 333, 336, and 337, located in a methane zone was chosen for the numerical modeling of simulated methane production. The presented static 3D model has been developed using Petrel Schlumberger software. The total resources of methane in the area amount to approximately 446.5 million of Nm³. Numerical simulations of methane production from the selected coal seams with hydraulic fracturing were conducted by means of Schlumberger ECLIPSE reservoir simulator. Based on the simulations, it was concluded that, in the first six months of the simulations, water is produced from the seams, which is connected with the decrease in the rock mass pressure. The process prompts methane desorption from the coal matrix, which in turn results in a total methane production of 76.2 million of Nm³ within the five-year period of the simulations, which constitutes about 17% of total methane resources (GIP). The paper also presents a detailed analysis of Polish legislation concerning the activities aimed at prospecting, exploring, and extracting the deposits of hydrocarbons.

Determining the characteristics of the dynamic behavior of carbon dioxide in a rock mass is a stage in the process of assessing a potential CO₂ storage reservoir. The aim of this study was to analyze the process of CO₂ storage in saline aquifers of the selected regions of the Upper Silesian Coal Basin in Poland. The construction of dynamic simulation models was based on static models of real deposit structures developed on a regional scale. Different simulation variants of the CO₂ storage process were adopted, varying in terms of injection efficiency and duration of individual simulation phases. The analysis examined the influence of the degree of hydrodynamic openness of the structure on the CO₂ storage process, in each of the variants. The results of numerical simulations showed that among the three analyzed geological formations, the Dębowiec formation is the most prospective for potential CO₂ storage and is characterized by the most favorable geological and hydrogeological parameters. In the best variant of the simulation, in which the safety of CO₂ storage in the rock mass was taken into account, the total amount of CO₂ injected in a single directional well was approximately 8.54 million Mg of CO₂ during 25 years of injection.

The region of Upper Silesia, located in southern Poland, is characterised by very high emissions of carbon dioxide into the air—the annual emission exceeds 33 Mt CO₂ and the emission ‘per capita’ is 7.2 t/y in comparison to the EU average emission per capita 6.4 t/y and 8.4 t/y for Poland in 2019. Although in the region there are over 100 carbon dioxide emitters covered by the EU ETS, over 90% of emissions come from approximately 15 large hard coal power plants and from the coke and metallurgical complex. The CCUS scenario for Upper Silesia, which encompasses emitters, capture plants, transport routes, as well as utilisation and storage sites until 2050, was developed. The baseline scenario assumes capture of carbon dioxide in seven installations, use in two methanol plants and transport and injection into two deep saline aquifers (DSA). The share of captured CO₂ from flue gas was assumed at the level of 0.25–0.9, depending mainly on the limited capacity of storage. To recognise the views of society on development of the CCUS technologies in Upper Silesia, thirteen interviews with different types of stakeholders (industry, research and education, policy makers) were conducted. The respondents evaluated CCU much better than CCS. The techno-economic assessment of CCUS carried out on a scenario basis showed that the economic outcome of the scenario with CCUS is EUR 3807.19 million more favourable compared to the scenario without CO₂ capture and storage.