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In response to the occurrence of selective grinding phenomena in polymetallic complex ores and the lack of associated research on complex ores and their constituent minerals, an investigation was conducted based on the motion theory of grinding media and the principles of selective grinding. The grinding characteristics were elucidated using metrics such as the breakage rate, grinding speed, and the t10 parameter of the ground product. The relationship between the grinding characteristics of polymetallic complex ores and their component mineral, including pyrrhotite, sphalerite, and quartz, under throw grinding conditions was investigated. The results show that during dropping state, sphalerite enhances the ore comminution effect, indicating that the presence of sphalerite plays a positive role in ore crushing, whereas pyrrhotite and quartz diminish the ore comminution effect, meaning their presence exerts a negative influence on ore crushing. The particle size characteristics of the grinding products of different constituent minerals all affect the particle size characteristics of the ore grinding products, with sphalerite showing a more significant impact on the ore's grinding characteristics. The grinding rate of both the ore and its constituent minerals exponentially decreases with prolonged grinding time, reaching a threshold when the grinding time reaches 4 minutes, where the rate of decrease rapidly slows. These findings can provide theoretical guidance for subsequent research on the optimization and control of grinding polymetallic complex ores under throw grinding. [ABSTRACT FROM AUTHOR]

Gossan discarded from mining processes result in metal resource wastage, and its long-term stacking causes environmental hazards. Therefore, this article considers zinc-containing gossan as the research object. The ore was roasted to prepare primary zinc ferrite products and sulfuric acid leaching was performed for purification. Then, XRD analysis was performed to characterize the purified products. The results indicated that the effect of sulfuric acid concentration on the purification of the products was related to its zinc ferrite content. Furthermore, the effect of leaching temperature on the purification of zinc ferrite products was related to sulfuric acid concentration; the lower the sulfuric acid concentration, the more considerable the effect of leaching temperature. The conditions suitable for purifying the products through sulfuric acid leaching are as follows: sulfuric acid concentration of 140 g/L, liquid–solid ratio of 4:1, leaching temperature of 80 °C, leaching time of 120 min, and stirring speed of 300 rpm. This article determines the factors affecting the purification of zinc ferrite by sulfuric acid leaching along with the optimal purification conditions. The findings presented herein provide a theoretical foundation for the development of new processes for preparing zinc ferrite, which has considerable industrial application value. [ABSTRACT FROM AUTHOR]

Gossan ore is typically abandoned after mining, which not only increases mining production costs but also wastes mineral resources, and its long-term accumulation can easily lead to environmental pollution hazards. Therefore, this paper takes zinc-containing gossan ore as the research object and, based on the high content of zinc and iron minerals in gossan ore, this study conducts a roasting experiment to prepare ZnFeO4. X-ray diffraction is used to characterize and analyze the ZnFeO4 sample prepared by roasting zinc-containing gossan ore. The experimental results indicate that controlling the particle size of the roasted ore sample to −0.074 mm can effectively remove impurities and facilitate the reaction. The influence of roasting temperature and time on the formation of ZnFeO4 is remarkable. The conditions for roasting zinc-containing gossan ore to maximize the ZnFeO4 content are as follows: −0.074 mm particle size ore sample, reaction zinc/iron molar ratio of 1:2, mechanical activation time of 120 min, roasting temperature of 1050 °C, and roasting time of 120 min. These findings provide new ideas for the utilization of gossan ore and lay a theoretical foundation for the efficient development and utilization of difficult-to-select zinc-containing gossan ore. [ABSTRACT FROM AUTHOR]

Based on the JK Drop Weight test and principle of selective crushing, a multicomponent complex ore with its component minerals, i.e., pyrrhotite, sphalerite, and quartz, was used to explore the impact crushing characteristics and relationship between the complex ore and its component minerals. Results show that the order of impact crushing resistance is quartz > pyrrhotite > ore > sphalerite. The particle-size-distribution characteristic curve of ore crushing products is always "sandwiched" between the curves of pyrrhotite, sphalerite, and quartz within the same feed-size range. When the particle size is −63 + 53, −45 + 37.5, −31.5 + 26.5, and −22.4 + 19 mm, the component mineral pyrrhotite has a negative effect on the impact crushing of ore, while the component mineral sphalerite has a positive effect. When the particle size is −16 + 13.2 mm, the component mineral pyrrhotite has a positive effect on the crushing effect of the ore, while the component mineral sphalerite has a negative effect. The component mineral quartz always has a negative effect on the impact crushing effect of ore in all the studied particle sizes. [ABSTRACT FROM AUTHOR]

Based on batch grinding method and normalization idea, a conical ball mill is used and a quantitative separation method of grinding characteristics of multi-component complex ore is proposed. The results show that the feed sizes of polymetallic complex ore have an obvious influence on the particle size distribution of intermediate grinding products in the early stage of grinding. However, the influence of the feed size is relatively insignificant on the particle size distribution of intermediate grinding products in the middle and late grinding stages. The grinding product t10 is negatively correlated with the feed sizes of ore when the grinding force is applied to the ore. At the same time, it has a simple positive linear relationship with the grinding time. The contribution rates of component minerals pyrrhotite, sphalerite and quartz to the grinding characteristics of the ore are 28.64%~37.74%, 39.93%~51.84%, 16.07%~28.39%, respectively. Therefore, the order of contribution of component minerals to the grinding characteristics of ore is sphalerite > pyrrhotite > quartz. The results provide new insights for the subsequent study of grinding characteristics of multi-component complex ores. [ABSTRACT FROM AUTHOR]

The relationship between the grinding characteristics of polymetallic complex ore and its component minerals, pyrrhotite, sphalerite, and quartz, under the action of abrasion was studied, based on batch grinding experiments and theoretical analysis methods of selective grinding. The results show that when the polymetallic complex ore was subjected to the action of abrasion, the crushing effect of ore was enhanced by the existence of sphalerite, that is, sphalerite plays a positive role in the crushing effect of ore. The crushing effect of ore was reduced by the existence of pyrrhotite and quartz, that is, pyrrhotite and quartz plays a negative role in the crushing effect of ore. In addition, the sphalerite had a more prominent effect on the grinding characteristics of the ore. The grinding speed of ore and its component minerals decreased exponentially with the grinding time, and the instantaneous grinding speed of 0 min was negatively correlated with the feed sizes. The rapidly decreasing trend of the grinding speed reached the threshold when the grinding time reached 4 min. The results can provide some theoretical guidance for the study of grinding characteristics of multi-component complex ores in subsequent grinding process. [ABSTRACT FROM AUTHOR]