###### Abstract  
Insufficient stability of the top plate at the corner of an easily combustible coal seam comprehensive mining face may lead to a natural fire within the goaf. While corner sealing is crucial for minimizing air leakage, current sealing methods struggle to effectively prevent such leakage. Additionally, the distribution characteristics of the oxidation zone in the goaf after sealing are unclear, making it difficult to control the extent of the oxidation zone. To address these issues, a new type of inorganic paste filling material was developed, taking into account the conditions of the Cuncaota II Mine. Various corner-filling schemes were developed, and numerical simulations were used to study the effects of different corner-filling strategies and varying filling interval distances on the width of the oxidation zone in the goaf. Based on these findings, a working face corner-filling technology was proposed and applied to the 22,122 working face. The research results indicate that the mountain sand-based paste filling material, using mountain sand as the filling aggregate and cement and fly ash as the binding materials, not only meets the pumping requirements but also exhibits excellent self-supporting characteristics, thereby addressing the corner filling needs of the working face. The width variation in the oxidation zone in the goaf is influenced by the position and interval distance of the corner filling, showing a pattern of initially decreasing and then increasing with the rise in the filling interval distance, reaching a minimum at a filling interval of 50 m. Field observation data demonstrate that, following the application of the aforementioned filling technology, the width of the oxidation zone in the goaf of the 22,122 working face is reduced by 37.5%, and air leakage decreases by 66.7% compared to the unfilled condition. This technology effectively narrows the range of the oxidation zone in the goaf, ensuring the safety of working face production. a 2023 13 13216 14 November  
consistently posed a significant challenge in mitigating spontaneous combustion and fires originating from residual coal in goat areas [10; 11]. Understanding the relationship between internal airflow and resistance within the goat area indicates that increasing resistance can fundamentally diminish air leakage [12]. Filling and sealing the corners of the working face constitute reliable methods for enhancing resistance. Safely and efficiently sealing the pathways of air leakage at the corners of the working face to reduce air infiltration into the goat has become a critical aspect of ensuring the secure extraction of coal in mining operations. The currently prevalent methods for corner sealing mainly consist of building cement walls and applying high-molecular-weight materials. However, these sealing techniques face problems, such as an insufficient sealing efficacy, an extensive construction effort, and high-molecular-weight materials being prone to self-ignition. In this context, the potential use of inorganic paste materials with proper fluidity, strong self-supporting properties, and appropriate strength for filling corners in the working area and sealing the main air leak passages in the goat should be evaluated. Research into inorganic paste materials for use as coal mine filling materials was initiated by scholars in the 1950s [13; 14]. Different types of inorganic filling materials, including fly ash paste, high-sand filling materials, foam cement, inorganic-cured foam materials, and ultra-high-water materials, were studied and provided a solid foundation for practical applications [15; 16]. [PERSON] and colleagues [17] utilized inorganic foaming filling materials to seal ventilation channels in the goat, using mobile grouting technology. This refined inorganic filling material significantly reduced the initial setting time, effectively addressing the issues of spontaneous combustion and fires in coal seams.