Background  The engineering-oriented, full flowsheet coal-based carbon capture, utilization, and storage (CCUS) technology is the key to efficient, clean coal utilization and carbon emission reduction. It represents a major technology that is urgently needed to ensure the energy security of China and achieve the strategic goals of peak carbon dioxide emissions and carbon neutrality of the country. Based on previous research efforts of the authors’ team, this study reviews the current status of this technology, reveals its integration mechanisms, and attempts to establish a pattern and scheme for CCUS cluster deployment in coal energy bases. Furthermore, it discusses the future development directions and technical challenges of the full flowsheet coal-based CCUS technology.

Advances  The key links of engineering-oriented, full flowsheet coal-based CCUS technology include energy-saving, highly adaptable coal-based CO₂ capture, safe and efficient geologic CO₂ sequestration in coal seams, and full and cost-effective CO₂ utilization in coal mining areas. The integration of this technology is achieved by the coupled control of three mechanisms: source-sink matching, technical parameter matching, and system optimization. Specifically, the source-sink matching mechanism enables the physical connection of coal-based CCUS facilities through multidimensional, multi-constraint pathway optimization. The technical parameter matching mechanism, using end-to-end coordinated design of critical operational parameters for carbon capture, storage, and utilization, achieves both the stable overall operation of physically connected facilities and the establishment of technical chain parameters. The system optimization mechanism allows for the dynamic optimization of the technical chain and the construction of optimal system configurations using big data platforms, optimization models, and intelligent algorithms. The three mechanisms exhibit strong interdependencies and mutual feedback. The technical pattern of the full flowsheet coal-based CCUS technology possesses distinct characteristics, including CO₂ capture from coal-fired or coal chemical industrial sources, geologic CO₂ sequestration in coal-bearing basins or coal seams, and CO₂ utilization in coal mining areas. This technology is implemented as CCUS clusters in coal energy bases. The CCUS clusters in large-scale coal bases, exemplified by the Junggar and Ordos basins, are expected to provide critical technical support for the low-carbon, high-quality development of China's coal industry.

Prospects  The deployment of CCUS clusters in large coal bases represents the mainstream development direction of the full flowsheet coal-based CCUS technology, with the connotation comprising: (1) low-cost CO₂ capture; (2) safe and efficient geologic CO₂ sequestration in deep, depleted coalbed methane (CBM) or coal-measure gas reservoirs within coal-bearing basins, and (3) high-value, integrated utilization of CO₂ in coal mining areas. Additionally, major directions for the technology expansion include: (1) enhanced CBM recovery (ECBM) driven by tail gas from the coal chemical industry and CO₂ sequestration; (2) ECBM by injecting flue gas from oxygen-enriched combustion (flue-gas ECBM) and CO₂ sequestration, (3) efficient CO₂ capture and large-scale CO₂ conversion and utilization for peak shaving via coal-fired power generation in new energy bases; and (4) CO₂ capture from coal-fired power generation bases coupled with carbon and energy storage in abandoned mine goafs.