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Compared with the traditional pyrometallurgical process, copper bioleaching has distinctive advantages of high efficiency and lower cost, enabling efficiently extracts of valuable metal resources from copper sulfides. Moreover, during long-term industrial applications of bioleaching, many regulatory enhancements and technological methods are used to accelerate the interfacial reactions. With advances in microbial genetic and sequencing technologies, bacterial communities and their mechanisms in bioleaching systems have been revealed gradually. The bacterial proliferation and dissolution of sulfide ores by a bacterial community depends on the pH, temperature, oxygen, reaction product regulation, additives, and passivation substances, among other factors. The internal relationship among the influencing factors and the succession of microorganism diversity are discussed and reviewed in this paper. This paper is intended to provide a good reference for studies related to enhanced bioleaching.

As an environmentally compliant hydrometallurgical process, in situ leaching is extensively used by the mining industry to recover rare earth from weathered crust elution-deposited rare earth ore. In the in situ leaching system, the pore structure plays a dominant role in the permeability of the rare earth orebody and is one of the most important factors that influence the leaching performance. To study the pore structure characteristics of the rare earth ore, an undisturbed ore sample was scanned using X-ray micro-computed tomography. Based on the image processing techniques, visualization of the pore structure was realized and several parameters of 2D and 3D pore structures, such as porosity, pore volume, length, width, aspect ratio, and orientation, were obtained and statistically analyzed. The ball-and-stick model of large pore clusters was built by the maximal ball algorithm, and some of their detailed characteristics were obtained. The results indicate that the pore structure of weathered crust elution-deposited rare earth ore exhibits a multi-scale and strong heterogeneity characteristic. The distribution characteristics of pores between the vertical direction and the horizontal direction are obviously different. The small pores are more prevalent in number, but they make only a small contribution to the total pore volume. In addition, the orientation of the pores is anisotropic in both vertical and horizontal directions. Furthermore, the ball-and-stick model reveals that large pore clusters are composed of several interconnected void spaces, and most of them are small and irregular.

In order to research the repair control technology of the inclined shaft with soft surrounding rock, the inclined shaft soft roadway of one phosphate mine in Hubei is taken as an example to study the damage characteristics, the deformation mechanism of the surrounding rock and repair control technology of it. The X-ray diffraction was employed to analyze the mineral components of the surrounding rock, also the surrounding rock contains clay minerals, which are easy to swell when in contact with water. The roadway mainly presents the damage characteristics of roof subsidence, two side walls extrusion, U-steel arch set bend or break, etc. The whole section double arch synergy reinforcement technology method of “sprayed concrete + grouting + anchor bolt + anchor cable” is proposed. And the technical parameters of the repair scheme are determined by theoretical analysis, engineering analogy and engineering practice. The numerical simulation is adopted to verify the feasibility of the whole section double arch synergy reinforcement scheme. The application results show that the large deformation roadway can be effectively controlled by the combined support scheme, which can provide certain references significance for similar engineering.

The migration of heavy metals and loss of valuable resources have become indispensable limitations to the developments of metal mines because of failing to remediate tailings ponds. Furthermore, serious environmental pollution from mine drainage water, soil during metal recovery from tailings by conventional acid leaching processes cannot be ignored. Thus, in this study, to recover valuable metals and reduce pollution, a cleaner metal extraction method from copper sulfide tailings using a combined leaching method employing ammonia solution and a novel strain of alkaline bacteria under alkaline condition was explored. The phylogenetic tree of a novel strain of alkaline bacteria isolated from tailings ponds at the Yangla Copper Mine in China was constructed from 16s rDNA sequence, and its optimal cultivation conditions and leaching characteristics were determined. A comparison leaching with alkaline bacteria, ammonia or a combination of the two clearly indicated that copper recovery was remarkably better with combination that Cu extraction rate increased from 4.42% (48 days, ammonia leaching) or approximately 20% (30 days, alkaline bacterial leaching) to 29.57% (30 days, combined leaching). The leaching mechanisms were discussed briefly. A synergistic effect between the alkaline bacteria and the ammonia solution was confirmed, especially at a lower ammonia concentration (30 g/L to 60 g/L). In addition, high ammonia concentration (>60 g/L) inhibited bacterial activity and even killed the bacteria. Although the mechanism of combined leaching still requires intensive study, the results of our exploratory experiments could significantly contribute to a green recovery method from tailings.

The commercial application of copper bioleaching, an environmentally-friendly approach for low-grade and secondary mineral resources recycling, has increased worldwide since the 2000s. As the world’s second-largest economic entity and the largest developing country, China has the largest demand for metal resources, significantly advancing the theory and industrial technology of copper bioleaching. This paper reviews the exploration and application of copper bioleaching in China. Two typical bioleaching applications and technological processes, bioheap leaching at the Zijinshan Copper Mine and bioheap leaching at the Dexing Copper Mine, are introduced. The considerable research completed by researchers is summarized, especially focusing on the isolation and identification of leaching bacteria, the bioleaching mechanism and interface reactions, multistage percolation behavior, bioleaching system reconstruction, the multiphysics coupled model, and enhanced copper bioleaching from waste printed circuit boards (WPCBs). Based on this investigation in China, key trends and prospects in copper bioleaching—such as efficiency improvement, environmental protection, and improved technology applications—are proposed.