Recovery of Synthetic Diamonds from Fines of Natural Stones Processing

Abstract

Objective: The objective of this study is to investigate the flotation process of the fines from the processing of natural stones - Fibro, and to propose a methodology to recovery synthetic diamonds present in it. For this, this research analyzes the influence of the amount of solid mass in the pulp and the amount of reagents used in the process. Theoretical Framework: The productive chain of natural stones generates millions of tons of Fibro annually, which can cause environmental damage if not disposed of or treated properly. Considering that the principles of circular economy are relevant in the pursuit of sustainable development of the sector, it is emphasized that Fibro contains several mineral resources that can be used in other productive chains. In addition to the rock powders resulting from processing, there are other particles of interest such as synthetic diamond. The synthetic diamonds present in Fibro come from the diamond tools used in rock sawing and polishing. These diamond particles have a high added value, and some recovery methods have been implemented to capture these grains for reuse. Among the methods used for this purpose, flotation has obtained the best results in previous studies. Method: The methodology adopted for this research begins with the collection and sampling of the Fibro in the natural stone production industries. Then, this material was classified granulometrically through sieving, and the samples were then subjected to the flotation process. In flotation, the percentage of solids in the pulp and the amounts of collector and frother used in the process were tested. All untested parameters were kept constant, and only the variables under investigation were modified at different levels. The methodology followed an experimental design and it was applied regression models and response surfaces for data modeling. Results and Discussion: The results show that the most efficient solid percentage was 35% in conditioning and 25% in flotation. Regarding the quantities of reagents tested, the model generated by the response surface indicates which levels obtained the best results in terms of concentrate recovery rate. It was also noted that the amount of collector had little influence on the process, which can be inferred by the natural hydrophobicity of the diamond. Implications of the Research: The implications of this research include economic benefits for the natural stones industry from the possibility of entering a new market in the sector. As well as advances in circular economy by reusing industrial waste and developing new technologies for the use of these materials. These results have the potential to impact industrial sustainability and can expand the mining and metallurgy sector. Originality/Value: This study contributes to the mining industry by proposing an innovative flotation methodology to recover synthetic diamonds from the fines of processing of natural stones. The relevance and value of this research are evidenced by its ability to provide a practical and efficient solution, with potential positive impact on circular economy and industrial sustainability.