Application basis and research progress of fractal theory in mineral processing

With the exploitation of mineral resources, some problems, such as the difficulty of mineral resources development and the difficulty of mine solid waste treatment, have seriously restricted the green, economic, efficient and sustainable development of mineral processing. In order to promote the in-depth development of mineral processing, some researchers try to draw lessons in theories and methodologies from other disciplines in their mineral processing related studies. With the aim of meeting the development needs of mineral processing industry, these explorations and attempts are expected to benefit the upgradation and innovation of the theory and research methods in mineral processing, which is therefore conductive to the industrial practices. Fractal theory, a typical nonlinear science, is widely used in the study of various irregular phenomena in nature. In mineral processing field, some researches have studied various fractal phenomena in many technological links throughout the whole process (including the ore sorting, crushing and grinding, pulp conditioning and flotation, sedimentation, filtration, etc.). Relevant research results have laid an important foundation for decoupling some technological processes in mineral processing, clarifying the underlying mechanisms, and realizing the regulation and optimization of beneficiation processes. In general, the application of fractal theory in some technological links in the mineral processing field is still at the theoretical research and experimental stage, most of the research results have not been applied to production practice. Some researchers, meanwhile, lack a comprehensive and profound understanding of fractal theory and its application approaches and prospects in the mineral processing, which hinders the research and development of fractal theory in mineral processing. Therefore, there is still much room for the development of fractal theory in the breadth and depth of related research in the mineral processing field. From the perspective of the basic definition of fractal theory, this review focuses on some unit links with fractal characteristics, such as self-similarity in mineral processing technology. It divides each unit link into “ore sorting, grinding and filtering” and “slurry mixing flotation and floc sedimentation” for research according to the conditions, such as the degree of dryness and humidity of the environment, the size of ore particles and whether the coagulation process of fine mineral particles is involved. While introducing various fractal phenomena and their changing laws in different process links, the development trends of basic research on the application of fractal theory are deeply summarized, focusing on the relevant problems of slurry coagulation behavior research based on fractal theory. According to the existing research, the development direction of fractal theory in the future of slurry coagulation theory research, as well as in the digital and intelligent production process of mineral processing is prospected.