Heat Exchange Evaluation at Thermo-Adhezion Method of Extraction of Diamond Raw from Kimberlite Ore
At a Glance
Section titled âAt a Glanceâ| Metadata | Details |
|---|---|
| Publication Date | 2018-02-27 |
| Journal | Mechanical Engineering Research |
| Authors | P. P. Sharin, Đ. Đ. ĐДбДЎДĐČ, G. M. Nikitin, Đ. Đ. ĐĐžĐœĐŸĐșŃŃĐŸĐČ, M. P. Akimova |
| Institutions | Yakut Scientific Research Institute of Agriculture, Institute of Physico-Technical Problems of the North named VP Larionov |
| Analysis | Full AI Review Included |
Technical Documentation & Analysis: High-Selectivity Diamond Extraction via Thermo-Adhesion
Section titled âTechnical Documentation & Analysis: High-Selectivity Diamond Extraction via Thermo-AdhesionâExecutive Summary
Section titled âExecutive SummaryâThis research validates a highly selective thermo-adhesion method for extracting raw diamond grains from kimberlite ore, leveraging the extreme thermal properties of diamond.
- Core Principle: The method relies on the massive thermal conductivity ($\lambda$) contrast between diamond (1001-2300 W/(m·K)) and accompanying minerals (typically < 8 W/(m·K)).
- Selectivity: Diamond exhibits a thermal conductivity 2-3 orders of magnitude ($10^2$ to $10^3$) higher than waste rock, ensuring high selectivity during extraction.
- Mechanism: High heat flow through the diamond particle causes rapid, localized melting of the thermo-adhesion substance (rosin) on a conveyor belt, fixing the diamond while the low-$\lambda$ minerals remain unfixed.
- Optimal Adhesion Material: Pure pine rosin is identified as the preferred thermo-adhesion substance, offering the highest contact strength (12.65 MPa) at an optimal adherence temperature (68 ± 5 °C).
- Process Parameters: Estimated calculations and experimental data confirm that using a roller-heater temperature up to 350 °C allows for conveyor belt speeds necessary for industrial throughput (up to $\approx 100$ mm/s).
- 6CCVD Relevance: This application requires materials with guaranteed, ultra-high thermal conductivity, making 6CCVDâs Single Crystal Diamond (SCD) the ideal component for high-efficiency thermal management and contact surfaces in next-generation sorting devices.
Technical Specifications
Section titled âTechnical Specificationsâ| Parameter | Value | Unit | Context |
|---|---|---|---|
| Diamond Thermal Conductivity ($\lambda$) | 1001 - 2300 | W/(m·K) | Core property enabling selective heat transfer |
| Kimberlite Thermal Conductivity ($\lambda$) | 2.1 | W/(m·K) | Baseline thermal conductivity of waste rock |
| Thermal Conductivity Ratio (Diamond/Kimberlite) | 476 to 1095 | N/A | Selectivity factor (2-3 orders of magnitude difference) |
| Preferred Adhesion Substance | Rosin (Pine), 100% | N/A | Highest measured adhesion strength |
| Rosin Melting/Adherence Temperature | 68 ± 5 | °C | Optimal temperature for selective melting |
| Rosin Adhesion Strength | 12.65 | MPa | Strength of contact (diamond-rosin) |
| Roller-Heater Maximum Temperature (Tâ) | 350 | °C | Experimental maximum for the heating element |
| Conveyor Belt Speed (V) | $\approx 100$ | mm/s | Speed required for melting at Tâ = 350 °C |
| Calculated Heat Transfer Duration (t) | 0.05 | sec | Used in theoretical modeling |
| Calculated Contact Area (S) | 1 | mmÂČ | Used in theoretical modeling |
Key Methodologies
Section titled âKey MethodologiesâThe thermo-adhesion method relies on precise heat transfer modeling and material characterization:
- Heat Transfer Modeling: Estimated calculations of heat flow (Q) were performed using a modified Fourierâs Law, modeling the heat transfer through the âheating element (Tâ) - diamond (or mineral) - thermo-adhesion substance (Tâ)â scheme.
- Thermal Property Justification: Thermal conductivity coefficients ($\lambda$) for diamond (1001-2300 W/(m·K)) and various related minerals (e.g., Quartz: 8.0 W/(m·K), Basalt: 1.3 W/(m·K)) were compared to justify the high selectivity.
- Adhesion Substance Testing: Various thermo-adhesion substances (pure rosin, rosin/beeswax, rosin/paraffin, pure paraffin) were tested for their melting/adherence temperature and contact strength with polished natural diamond.
- Strength Measurement: Adhesion strength tests were carried out using the normal tear-off method after curing the thermo-adhesion layer on the diamond surface at room temperature.
- Dynamic Experimental Validation: An experimental unit was used to validate the calculated relationship between the roller-heater temperature (T) and the necessary conveyor belt speed (V) to achieve selective melting of the adhesion layer.
6CCVD Solutions & Capabilities
Section titled â6CCVD Solutions & CapabilitiesâThe efficiency and reliability of the thermo-adhesion extraction method are fundamentally dependent on the consistent, ultra-high thermal conductivity of the diamond material. 6CCVD provides the engineered diamond solutions necessary to transition this research into robust industrial technology.
| Requirement from Research Paper | 6CCVD Solution & Capability | Value Proposition |
|---|---|---|
| Ultra-High Thermal Conductivity ($\lambda$ > 1000 W/(m·K)) | Single Crystal Diamond (SCD) | 6CCVDâs SCD offers guaranteed high thermal conductivity, providing the rapid heat transfer required for high-speed, selective melting in the Tâ heating element contact zone. |
| Large-Area Contact Surfaces (Conveyor belt integration) | Custom Dimensions & Thickness (Plates/wafers up to 125mm) | We supply large-format SCD or PCD plates, allowing for the design of industrial-scale heating elements and contact surfaces far exceeding typical lab sizes. Substrates up to 10mm thick are available. |
| Precision Contact Surfaces (Adhesion testing, uniform heating) | Precision Polishing (Ra < 1nm for SCD, < 5nm for PCD) | We ensure extremely low surface roughness, critical for consistent thermal contact (S) and reproducible adhesion strength measurements, minimizing variability in industrial sorting. |
| Integration of Heating Elements (Tâ Roller/Heater) | Internal Metalization Services (Au, Pt, Pd, Ti, W, Cu) | 6CCVD can deposit custom metal layers directly onto the diamond surface, enabling reliable electrical contacts or heat spreader integration for the high-temperature (up to 350 °C) roller-heater component. |
| Cost-Effective Large-Scale Components | Polycrystalline Diamond (PCD) | For applications where the absolute highest thermal conductivity is not required, or where larger areas are needed, 6CCVD PCD offers excellent thermal properties and mechanical robustness at competitive pricing. |
Engineering Support: 6CCVDâs in-house PhD team specializes in the thermal and mechanical properties of MPCVD diamond. We can assist with material selection, thermal modeling, and custom component design for similar high-speed mineral separation and thermal management projects.
For custom specifications or material consultation, visit 6ccvd.com or contact our engineering team directly.
View Original Abstract
In the work thermo-adhesion a method of selecting and extracting the grains of diamond from a mixture of related minerals is developed. The study presents estimates of the heat transfer of the proposed scheme extraction based on the difference between the thermal conductivity of diamond and related minerals. The high selectivity thermo-adhesion selection and extraction of diamonds with the division concentrate on useful component and waste rock is shown.