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Rock texture is a term representing the mineral grains, grain sizes, and matrices of rocks. Crushability properties of rocks are very important parameters on an industrial scale and they can be determined by different methods. This study investigated the effects of textural properties of rocks on their crushability. For this purpose, some physical and mechanical tests were carried out on 12 different rock samples, which were divided into igneous, metamorphic, and sedimentary rock groups. All rock samples were crushed by using jaw and roll crushers, and crushability indices (CI) and particle sizes (d50, d80) were determined for all rock samples. The textural properties of rocks were defined by using the texture coefficient (TC) approach on thin section images. The test results were statistically analyzed, and firstly the physical and mechanical properties were correlated with CI and TC, respectively. Positive linear correlations were found between TC and uniaxial compressive strength (UCS), Brazilian tensile strength (BTS), and Schmidt hammer hardness (SHH). When the rock samples were grouped based on their geological origins, there were strong or good linear relationships between CI and UCS and BTS for both the jaw and roll crushers. Then, TC was correlated with CI, d50, and d80. It was found that TC was influential on CI especially for the roll crusher. However, when the rocks were separated as igneous, metamorphic and sedimentary, strong linear relationships were found for both crushers. The same was observed for the relationship between TC and both d50 and d80; the correlation coefficients were higher and more reliable for the roll crusher than the jaw crusher. The results of this study showed that the textural properties of rocks are more influential on the results obtained in a roll crusher than a jaw crusher. However, more rock samples are required to verify the results of this study.

The use of mineral aggregates is related to the increasing demand in construction, railway and road infrastructures. However, mineral aggregates can appear to be of variable quality, directly affecting their suitability for respective earthwork applications. Since the production of mineral aggregates should ensure the standardized, high-quality requirements of the final product, rock-crushing mechanisms should be investigated in a detailed manner. In this context, the aim of the present study is to evaluate and analyze the geometric parameters of basalt aggregates as a result of several rock comminution processes. Basalt aggregates from two deposits in Poland were used in the study. The samples are differentiated regarding both lithological variances, mineral composition as well as the host rock’s tuff content. The rock comminution processes were conducted using two types of crushers, namely the laboratory-scale jaw and cone crushers. The feed for crushing was designed based on the original geometric grain composition and the separated feed in the form of flaky and non-flaky particles. The crushability test results demonstrated that the interparticle compression in the jaw crusher resulted in finer products compared to the one in the cone crusher. It was also observed that the flakiness and shape indexes decreased after crushing, both in the feed with the original geometric composition of the grains and those with flaky and non-flaky particles. Nevertheless, a higher flakiness index was obtained after the crushing of non-flaky particles and a lower one after the crushing of flaky particles. The flakiness index for grains below 16 mm after the crushing process was less than 10%, which indicates a more favorable result compared to the original feed. In addition, it was shown that flaky and non-cubical particles were accumulated in the finest (below 8 mm) and coarsest (above 20 mm) fractions in jaw and cone crushing processes, receiving flakiness and shape indexes ranging up to 80–100%. Finally, it was also observed that the lithological variances of the feed material have a significant impact on the particle size distribution of the product. More profoundly, basalt aggregates with a higher tuff content and weathering degree have a higher degree of crushing. The present study, in this context, provides accurate and satisfying information on understanding the crushing mechanisms of two important crushing equipment as well as their rock-crusher interactions.

There are a sufficient number of works devoted to modeling crushing machines. Nevertheless, the fact that there are a large number of working conditions, and the ongoing development of science and technology, require continuous improvement and specification of the models intended for crushing processes and those of the devices concerned. However, there are few studies related to single-roll gyratory crushers. Such crushers are promising for use in mines to crush rocks laid in the developed space. Mathematical modeling and optimization of the design parameters of the working chamber and the executive body (roll) of a single-roll gyratory shaft crusher, designed for crushing strong rocks, was performed in this paper. A differential equation was derived. As a result of its solution, the rational shape of the working chamber cheek of the single-roll gyratory crusher was established, representing a logarithmic spiral arc. Analytical expressions were derived to determine the rational rotation speed and productivity of the crusher under consideration. Expressions for calculating the kinematic load components acting on the roll were formulated. They are the periodic functions of the shaft rotation angle. The Fourier series expansion showed that the loads contained harmonics of the first, second, third and fourth orders. Using the concept of fuzzy sets, a multi-criteria optimization of the design parameters of the working chamber was performed, including the values of the eccentricity and the central angle of the beginning of the cheek profile. The variation coefficients of the kinematic components of the loads acting on the working body reduced, due to the optimal choice of the working chamber profile and the angular coordinates of the installation of the fixed cheeks. The torque reduced 1.67 times, while the radial load decreased 1.2 times.

This paper presents a detailed kinematic analysis of a double-toggle jaw crusher used for the primary crushing of hard and bulky materials. The study introduces an innovative mathematical modeling method for the motion of the mechanism’s components, eliminating the need for traditional decomposition into structural groups. General equations are developed to determine the positions, linear velocities, and angular displacements of the moving elements, providing a solid foundation for equipment design and study. The generated mathematical model was validated using real-world dimensions of an SMD-117-type jaw crusher and by comparison with simulation results obtained from Mathcad, Linkage, Roberts Animator, and GIM software. The results demonstrated a high degree of agreement between the calculated and simulated trajectories and linear velocities. The analysis of angular displacements and linear velocities confirmed the cyclic nature of the mechanism’s motion, characterized by sinusoidal variations and low oscillations, which are relevant for assessing variable loads. Through its rigorous approach and multi-source validation, the research makes a significant contribution to the development of more efficient, durable, and adaptable jaw crushers for modern industrial requirements.

Over the last few decades, the demand for energy-efficient mineral-processing methods has continued. The necessity to develop energy-efficient technologies for the mineral industry will increase in the future, considering the exhaustion of high-quality resources and severe environmental limitations. The subject of this study is crushing equipment. It is a complex of units designed to reduce the fraction of ore and non-metallic solid materials. It is also designed to make them more symmetrical in order to facilitate their transport and later use in production. Thus, the urgency of using crushers in mining and processing plants is clear, so it is relevant to find ways to optimize their operation and reduce energy consumption. This article presents a systematic review of the task of improving the energy efficiency of crushing units. This is achieved by studying modelling methods and results, the automation of crushing and grinding processes, and the wear reduction of crusher components. On the grounds of the reviewed sources, the main methods of increasing the efficiency of crushing units are identified. A mathematical model of the cone crusher was designed. The simulation error is less than 6%. A simulation experiment was carried out on the mathematical model. The dependences of the current and power of the crusher electric drive on the feeder capacity are determined; the graphs have a symmetrical position relative to the approximating curve (R2 ≈ 0.9).

Gyratory crushers are fundamental machines in aggregate production and mineral processing. Discrete Element Method (DEM) simulations offer detailed insights into the performance of these machines and serve as a powerful tool for their design and analysis. However, these simulations are computationally intensive due to the large number of particles involved and the need to account for particle breakage. This study aims to investigate the effect of particle shape and size distribution on the performance of a DEM model of a gyratory crusher. The selected study case corresponds to a primary gyratory crusher operating in a copper processing industry. As particle shapes, spheres and polyhedrons are used with a particle replacement scheme. This study utilizes two different size distributions, with variations also applied to the minimum particle size. The results are analyzed in terms of the impact of these factors on the power draw, mass flow, and product size distribution for each of the combinations explained. The findings demonstrate that particle shape primarily influences the product size distribution, whereas variations in particle size distribution have a pronounced effect on power draw, mass flow rate, and product size distribution. Based on the results, recommendations are provided regarding the selection of the minimum particle size. It is concluded that the minimum particle size should not exceed a third of the closed-side setting to ensure accurate and reliable simulation outcomes.

This study aims to investigate the effect of the shredding machine used on the recyclability of plastic fractions after primary crushing. This work presents a method for producing aggregates that has yet to be used in the plastics industry. This study included crushing of polymethylmethacrylate (PMMA), polyamide (PA-6), acrylonitrile butadiene-styrene (ABS), polycarbonate (PC), polystyrene (PS), and polypropylene (PP) waste in a jaw, a hammer, and a cone crusher. An analysis of the grain composition was carried out to characterize the obtained crushing products. The influence of feed size on the grain composition of the product and, only on the jaw crusher, the influence of the material used on the parameters of the crushing process was studied. This paper proposes a method to evaluate the grain composition and a way to assess plastic shredding capabilities based on machine kinematics and mechanical properties of a given material.

The construction industry is a major consumer of natural resources and a significant source of CO2 emissions. Although numerous studies have addressed cement reduction through supplementary materials, the replacement of natural aggregates has received less attention despite its high environmental relevance. Practical application of recycled aggregate concrete remains limited due to complex classification and testing requirements. This study investigates the use of locally crushed construction and demolition waste as aggregate for new structural concrete with minimal on-site preparation. The goal was to maximize recycled material utilization while ensuring adequate performance. Demolition materials from normal- and high-strength concrete, 3D-printed concrete, and fired clay bricks were crushed using jaw and impact crushers, and the entire particle size curve was incorporated into new mixtures. Two compositions were tested: 50% and 75% recycled aggregate combined with natural quartz sand, without increasing cement content. Compressive strength and density were evaluated at 28 and 90 days. High-strength concrete waste provided strengths close to the reference mixture, while normal concrete and brick aggregates resulted in lower but still structural-grade concretes. The strengths achieved ranged between 35 MPa and 73 MPa, which is between 48% and 98% of the reference value, respectively. A linear relationship was found between density and compressive strength, enabling estimation from simple measurements. The results confirm that uncontaminated demolition waste can be efficiently reused on site with limited testing, supporting circular construction and reduced environmental impact.

Comminution by gyratory crusher is the first stage in the size reduction operation in mineral processing. In the copper industry, these machines are widely utilized, and their reliability has become a relevant aspect. To optimize the design and to improve the availability of gyratory crushers, it is necessary to calculate their power and torque accurately. The discrete element method (DEM) has been commonly used in several mining applications and is a powerful tool to predict the necessary power required in the operation of mining machines. In this paper, a DEM model was applied to a copper mining gyratory crusher to perform a comprehensive analysis of the loads in the mantle, the crushing torque, and crushing power. A novel polar representation of the radial forces is proposed that may help designers, engineers, and operators to recognize the distribution of force loads on the mantle in an easier and intuitive way. Simulations with different operational conditions are presented and validated through a comparison with nominal data. A calculation procedure for the crushing power of crushers is presented, and recommendations for the selection of the minimum resolved particle size are given.

This study reports on the design optimisation of the swinging jaw crusher plate. Jaw crusher machines are used in the mining and construction industry for crushing rocks and mineral ores to the appropriate sizes for direct application or further processing. During the crushing process, large and non-evenly distributed impact forces occur, resulting from uneven feed patterns and nonhomogeneous material composition (varying hardness). Hence, the jaw plate experiences inhomogeneous stress distributions causing warping and fracture failure of the crusher plates. The plate warping reduces the crusher performance, resulting in low crusher efficiency, high cost of replacing the crushing plates, and higher energy consumption. In this study, the design parameters: plate profile, thickness, and the height of the jaw plate were optimised using ANSYS software. These design parameters were varied to analyse deformation and stress distribution during crushing. Design of experiment techniques was used to determine the optimal design parameters. Optimisation results showed that the optimal design parameters were: 40.06 mm thickness, 4.94 mm plate profile, and 996.21 mm height. An analysis using the optimal parameters produced the optimal outputs as 1.41 MPa for the maximum equivalent stress and 2.7 × 10 –8  m for the average total deformation. This study shows that the jaw crusher plate geometry influences the flow stress and deformation behaviour during the crushing process. The findings from this study provide the basis for future designs of swing jaw crushers for industrial applications.