Given the pressing demand for eco-friendly and low-carbon development in mining operations, decarbonizing the blasting techniques has emerged as a pivotal challenge. The effectiveness of rock fragmentation critically determines the ore size distribution, thereby exerting a decisive influence on the energy requirements of subsequent processing stages. Using Chengchao Iron Mine as a case study, this study developed a stope production carbon emissions model that quantitatively correlates D₅₀ particle size with critical operational parameters, including drilling power consumption, blasting explosive usage, and haulage equipment energy demand. By integrating carbon emission coefficients for associated energy and materials, the research systematically quantified process-wide carbon emissions influenced by fragmentation performance, ultimately determining 32.55 cm as the optimal D₅₀ particle size for minimizing carbon emissions. Subsequently, sixteen groups of orthogonal experiments were designed by varying blasthole length, stemming length, and toe spacing. A fluid-solid coupling algorithm was implemented to characterize the dynamic constitutive behavior of formations. Building on this foundation, ANSYS/LS-DYNA simulations were conducted to analyze the distribution of blast-induced fractures across various design schemes. Grayscale processing and binarization were applied to simulated fracture patterns to enhance rock block boundary contrast, followed by an adaptive multi-scale Canny algorithm for precise extraction of fragment-fracture interfaces. Finally, the boulder yield, fines fraction, and D₅₀ particle-size distribution for each experimental configuration were statistically analyzed to enable precise calculation of associated carbon emission intensities. Simulation data analysis reveals that carbon emissions across the 16 schemes range from 1.4391 kg CO₂/t to 1.6296 kg CO₂/t, with a pronounced inverse relationship between the oversize fragment proportion and fine ore generation efficiency. Subsequently, a fragmentation prediction model was developed using a PSO-ELM algorithm based on the experimental datasets. The NSGA-Ⅱ optimization method was employed to refine blasting parameters, yielding an optimal configuration that simultaneously minimizes carbon emissions and enhances fragmentation performance: a 166 m blasthole length, a 21.6 m stemming length, and a 2.0 m toe spacing. This configuration achieves a carbon emission intensity of 1.43617 kg CO₂/t, with an oversize fragment ratio of 18.83926% and a fine ore production rate of 17.28788%. The results confirm that the developed collaborative optimization approach substantially reduces whole-process carbon emission intensity during stope production while maintaining consistent operational efficiency. This research provides both a measurable technical framework that combines sustainable transformation with intelligent control to achieve the “dual carbon” target and actionable implementation guidelines for industrial practice.

This study investigates the mechanism by which detonation velocity and charge length influence blasting performance in muck pile blasting, aiming to optimize blast design parameters while enhancing explosive energy utilization efficiency and operational safety. By establishing a comprehensive evaluation system integrating fuzzy mathematics, the entropy weight method, and the analytic hierarchy process, this study analyzes the optimal ranges of detonation velocity and charge length that meet field construction requirements. Additionally, a mechanical model of muck pile blasting was developed using the discrete element software PFC. The study systematically examined stress wave propagation, fracture propagation, and energy transfer characteristics across various combinations of detonation velocity and stemming length. Field measurements of critical parameters, including blast vibration parameters, rock fragmentation distribution, and muck pile morphology, were conducted and cross-validated with simulation outputs, confirming both the engineering adaptability of optimal parameter ranges and the reliability of numerical modeling predictions. The experimental results demonstrate an optimal detonation velocity range (approximately 4500 m/s) for bull emulsion explosive in muck pile blasting operations, showing optimal compatibility with granite formations. Below this critical velocity threshold, insufficient explosive energy occurs, leading to increased oversize fragment generation in blasted rock masses. Excessive detonation velocities lead to elevated fine ore production rates due to disproportionately high peak stress-wave pressures. Furthermore, a critical correlation exists between charge length and bench height. Optimal fragmentation balance between the upper and lower bench sections is achieved when the charge length is 20% to 26% of the total bench height. Through targeted technical interventions, refined blasting implementation, and optimized adjustment of explosive detonation velocity coupled with charge length, significant enhancement of bench blasting performance can be achieved under existing burden and spacing. This research elucidates the coupling mechanism between detonation velocity and stemming length, establishing both theoretical foundations and practical guidelines for optimizing blasting parameters in open-pit mine muck pile blasting.

The slope stability is bound to be affected in the blasting process of open-pit mine, especially when the slope is in the karst area. In order to study the influence of karst on slope stability under blasting and based on Tangya limestone mine slope project, this paper takes the exposed karst at the 1014 m platform of the mine as the research object, and uses ANSYS/LS-DYNA finite element analysis software to conduct numerical simulation. Considering the effect of blasting vibration, the stress distribution of the surrounding rock is obtained, and the effects of blasting on slope stress, vibration velocity, rock damage and effective stress of slope with or without karst cave are compared. The results show that the force of the bench changes and stress concentration occurs for several times due to the existence of karst caves, but the stress value generated by the bench loads is only 7.6 MPa, which still cannot reach the degree of rock mass destruction. For monitoring points at different spatial locations, the difference of vibration velocity becomes larger due to the existence of karst caves, and the vibration velocity in the vertical direction changes more than that in the horizontal direction. In particular, the spatial locations of the monitoring points near the slope edge are more sensitive to this situation. The vibration velocity difference of the monitoring points on the slope edge is about 1 cm/s at most, which does not exceed the allowable vibration velocity. In the process of increasing blasting times, the damage inside the rock mass is also gradually increasing, and the damage is more obvious under the influence of karst caves. The larger the radius of karst area, the more blasting times, the more serious the damage. Compared with previous uniaxial compressive strength experiments, it is found that although the existence of karst caves will cause the change of stress value and stress concentration phenomenon, the peak effective stress generated is far lower than the uniaxial compressive strength of rock mass. In view of the influence of blasting process on slope stability, the support treatment measures of slope in karst area are put forward.