## 1 Introduction  
As global warming poses a significant threat to the earth's life systems, there is a consensus among countries worldwide to strictly control CO\({}_{2}\) emissions in order to minimize greenhouse gas output [1]. The CO\({}_{2}\) capture, utilization, and storage technology (CCUS) serves as a crucial greenhouse gas emission-reduction technology, playing a significant role in expediting carbon emission reduction, ensuring energy security, fostering ecological civilization, and achieving sustainable development. The CO\({}_{2}\) mineralization storage technology is widely regarded as one of the most promising and ideal methods, primarily due to its safety and stability. As a result, this technology finds extensive application in the ex situ mineralization and storage of CO\({}_{2}\) in industrial alkaline solid waste [2, 3, 4, 5]. Due to its abundant raw materials, high reactivity, small particle size, low energy consumption, and lack of need for activation and mechanical grinding, fly ash has emerged as a promising alkaline material for mineralizing and sequestering CO\({}_{2}\) in recent years [6, 7, 8, 9]. Nevertheless, studies have indicated that fly ash encounters challenges, including the multi-scale attenuation of the reaction rate and low mineralization efficiency, during the process of CO\({}_{2}\) mineralization and storage. Consequently, numerous domestic and international scholars have conducted extensive experimental research on the mineralization and storage of CO\({}_{2}\) using fly ash. Their studies have focused on investigating the evolution mechanism and factors that influence the mineralization reaction efficiency of fly ash and CO2. These studies have also shed light on the occurrence of the multi-scale attenuation of the reaction rate and the low mineralization efficiency phenomenon, thereby offering valuable theoretical guidance for enhancing mineralization efficiency. Existing research on the mineralization of CO2 in fly ash primarily concentrates on investigating the impact of various external factors, including temperature, pressure, CO2 flow rate, and water-to-solid ratio, on the efficiency of the process. Several scholars have examined the potential of utilizing fly ash mineralization as a means of storing CO2 at ambient temperature and low-pressure conditions. Although this approach does not necessitate the use of extensive chemical reagents, it does require elevated reaction temperatures and pressures to enhance the reaction rate, resulting in significant energy consumption. Consequently, this method is currently insufficient to meet the requirements of industrial applications [10; 11]. [PERSON] et al. investigated the use of water as the reaction medium in the fly ash and CO2 reaction system. They observed that CaO initially reacted with H2O, resulting in the formation of Ca(OH)2. Subsequently, Ca(OH)2 reacted with CO2 to form CaCO3. The presence of H2O significantly enhanced the mineralization reaction, effectively accelerating the reaction process and improving the kinetic characteristics of the reaction [12; 13]. Water serves as the reaction medium between alkaline solid waste and CO2, making the liquid-to-solid ratio (L/S) a crucial factor in determining mineralization efficiency. Previous experimental studies have highlighted that a low L/S ratio hinders the effective mixing of the slurry, leading to the inadequate transfer of calcium from the solid phase to the liquid phase. On the other hand, a high L/S ratio results in a low concentration of calcium ions in the solution, which is unfavorable for the mineralization reaction [14]. Increasing the temperature has a positive effect on the dissolution of CaO into the water phase and also enhances the reaction kinetics of the mineralization process. However, it is worth noting that the solubility of CO2 in the liquid phase decreases at higher temperatures. Therefore, solely raising the temperature does not necessarily lead to an improvement in the reaction efficiency [15].