# Complex Processing of Saponite Waste from a Diamond-Mining Enterprise
## 9 Conclusions  
The reprocessing of sludge is a major concern of the modern mining industry due to their environmental damage and decrease in enrichment process efficiency. In the case of diamond mining, it is especially relevant, due to the low yield of ore processing; thus, new methods of utilizing host rocks are required.  
Saponite mineral is a perspective secondary product which can be applied in construction, fertilizer production, ion-exchange and other applications. Thus, a sophisticated technology of its reprocessing and utilization should be developed. Due to the particle size of the sludge, it forms a stable suspension, which tends to swell, making processing more water-intensive; settlement in natural conditions may last more than 1000 years, which makes coagulant application necessary.  
Application of specially developed mineral coagulants can not only solve the problem, but it can enhance properties of saponite sludge for secondary product.  
The following conclusions can be briefly drawn from the investigations performed:  
1. Based on the granulometric and chemical composition of the ore and the suspension, a coagulant with specified physical and chemical properties was successfully synthesized.
2. The calcium aluminosilicate reagent is a promising coagulant for thickening clay mineral suspensions. The water was found to be purified to a level of 95%.
3. Due to the asrtingent properties of the synthesized inorganic mineral precipitator, the load on the walls of the dam is reduced. This protects it from further damage and leads to a decrease in the areas occupied by the tailing dump.
4. The condensed sediment can be reused by restoring its calcium component. This creates the opportunity to develop waste-free diamond mining.  
A.A.--development of a method for obtaining a calcium-aluminum-silicate reagent; K.K.--development of a method for determining the deposition rate of saponite pulp using a calcium-aluminum-silicate reagent; M.R.--therrochemical calculations; O.Z.--synthesis of a calcium-aluminum-silicate reagent; interpretation of the mineral composition of the obtained reagent sample; O.K.--calculation of kinetics; A.P.--conducting an experiment on the deposition of saponite suspension with a developed coagulant and sealer. All authors have read and agreed to the published version of the manuscript.  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**No.** & **Oxide** & **Content, wt\%** \\ \hline
1 & SiO\({}_{2}\) & 28.86 \\ \hline
2 & Al\({}_{2}\)O\({}_{5}\) & 6.47 \\ \hline
3 & MgO & 3.83 \\ \hline
4 & Fe\({}_{2}\)O\({}_{5}\) & 5.8 \\ \hline
5 & CaO & 52.89 \\ \hline
6 & K\({}_{2}\)O & 0.44 \\ \hline
7 & TiO\({}_{2}\) & 0.44 \\ \hline
8 & Na\({}_{2}\)O & 0.26 \\ \hline
9 & P\({}_{2}\)O\({}_{5}\) & 0.07 \\ \hline \hline \end{tabular}
\end{table}
Table 5: The chemical composition of the condensed product.  
Funding: This research was funded by BMBF, grant No. 03Z22 FN12.  
**Acknowledgments:** The authors would like to express their gratitude to the following: [PERSON] an employee of the Center for Collective Use of the SPMU, for his assistance in studying the mineral composition of the ore, obtaining a laboratory sample of the reagent, and determining the granulometric composition of saponite pulp suspensions;and [PERSON], researcher at the SPMU Research Center on \"Problems of processing of mineral and technogenic resources\" for assistance in the study of the morphological composition of ore using the TESCANVega electron scanning microscope. Financial support for this study by the German Federal Ministry of Education and Research (BMBF, grant No. 03Z22 FN12) is gratefully acknowledged.  
**Conflicts of Interest:** The authors declare no conflict of interest.