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Compressed carbon dioxide energy storage in aquifers (CCESA) is a new large-scale energy storage technology derived from geological carbon dioxide sequestration, compressed air energy storage in aquifers, and compressed carbon dioxide energy storage. However, there have been no practical applications so far. In this study, we present a numerical model that simulates the whole process of gas filling period and daily cyclic period of the subsurface system of CCESA with two wellbores and two aquifers, and reveal the hydrodynamic and thermodynamic properties, energy efficiency, and the influences of wellbore and aquifer locations, injection temperature and injection rate on system performance. The results show that the fluctuation ranges of pressure and temperature in the wellbores and aquifers increase with time, especially in the high-pressure aquifer where the maximum and minimum pressures are 15.96 and 9.78 MPa after 200 days of cycles. The maximum energy efficiency of the system can reach 1.022. Within 100 days of cushion gas filling and 200 days of cycles, the maximum horizontal CO 2 transportation distance in aquifers is 198.1 m, indicating a strong sealing effect of the system. The system energy efficiencies of the two target aquifers are very similar for different vertical intervals, while the variations in wellbore pressure and temperature differ significantly, which affects the energy efficiency and stability of the surface plant. Low-temperature CO 2 injection is beneficial to improving the energy efficiency of the system. Increasing injection-production rate can directly improve power generation rate, and energy efficiency is also higher for higher flow rates. • The overall performance of compressed CO2 energy storage in aquifers is studied. • Energy efficiency of the system is high, often exceeding 1.0 • CCESA is a carbon-negative, space-saving, and high-efficiency system. • CCESA can achieve CO2 sequestration and energy storage synergistically. [ABSTRACT FROM AUTHOR]

To study the operational characteristics of inter-seasonal compressed air storage in aquifers, a coupled wellbore-reservoir 3D model of the whole subsurface system is built. The hydrodynamic and thermodynamic properties of the wellbore-reservoir system during the initial fill, energy injection, shut-in, and energy production periods are analysed. The effects of well spacing and air injection temperature on the seasonal storage process are investigated. The results show that the ranges of variation in wellbore-aquifer pressure and temperature are within the acceptable level during the whole operational process. The maximum wellhead pressure, reaching 13.08 MPa, occurs during the first injection in the initial fill period. The temperature of the air released from the wellhead is 6 °C lower than the initial injection temperature due to heat loss. The horizontal transport distance of injected air in the aquifer is 2173.5 m away from the central well at the end. The overall energy storage efficiency is 94.3% and the energy lost by the wellbore during production is 0.09%. Parametric analysis shows that the system has an optimal performance at a well spacing of 150 m. The energy storage efficiency is 5% higher at an air injection temperature of 20 °C than 50 °C. The results strongly confirm the feasibility of IS-CAESA. • A numerical model of inter-seasonal compressed air energy storage in aquifers is developed. • The feasibility of inter-seasonal compressed air energy storage in aquifers is firstly verified by numerical method. • Full cycle properties of inter-seasonal compressed air energy storage in aquifers are first revealed. • The subsurface system of inter-seasonal compressed air energy storage in aquifers can reach high energy efficiency. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: To test the feasibility of MRI-guided high intensity focused ultrasound ablation for adenomyosis. Materials and methods: Patients with symptomatic adenomyosis were treated with MRI-guided high intensity focused ultrasound (MRIgHIFU). Under conscious sedation, MRIgHIFU was performed by a clinical MRI-compatible focused ultrasound tumour therapeutic system (JM15100, Haifu® Technology Co. Ltd., Chongqing, China) which is combined with a 1.5T MRI system (Magnetom Symphony, Siemens Healthcare, Erlangen, Germany). MRI was used to calculate the volume of the uterus and lesion. Non-perfused volume of the targeted lesions was evaluated immediately after MRIgHIFU. Patient symptoms were assessed using symptom severity score (SSS) and uterine fibroids symptoms and quality of life questionnaire (UFS-QOL). Results: Ten patients with mean age of 40.3±4 years with an average lesion size of 56.9±12.7mm in diameter were treated. Non-perfused volume and the percentage of non-perfused volume obtained from contrast-enhanced T1 Magnetic resonance images immediately post-treatment were 66.6±49.4cm3 and 62.5±21.6%, respectively. The mean SSS and UFS-QOL showed significant improvements of 25%, 16% and 25% at 3, 6 and 12 months follow up, respectively, to pre-treatment scores. No serious complications were observed. Conclusion: Based on the results from this study, MRIgHIFU treatment appears to be a safe and feasible modality to ablate adenomyosis lesion and alleviate its symptoms. [Copyright &y& Elsevier]