VMP-1750 Plasma-Assisted Melting Furnace for Metal Recovery from Oxide Slags with Induction Heating and Reverse-Polarity Transferred Arc Plasma
The VMP-1750 furnace is engineered to address the challenge of extracting valuable metals from complex oxide slags by integrating advanced plasma and induction heating technologies within a controlled high vacuum environment. This system enables precise melting of slags in a graphite crucible while employing a reverse-polarity transferred arc plasma to electrolytically separate noble metals from the slag matrix.
The furnace operates inside a stainless steel vacuum chamber equipped with a quartz observation window and multiple ports for vacuum pumping and gas management. Induction coils provide up to 15 kW of power with automatic PID temperature control, while a water-cooled copper electrode serves as the cathode. The arc generator delivers a DC output up to 315 A for plasma generation, facilitating high-temperature electrolysis with a water-cooled anode electrode. A rotary vane vacuum pump maintains vacuum levels around 10e-2 torr, supported by a capacitance diaphragm gauge and integrated flowmeter. Cooling is managed by a recirculating water chiller with a 58 L/min flow rate.
Key Features
- Stainless steel vacuum chamber (Ø315 mm × 315 mm H) with quartz observation window and multiple vacuum/gas ports
- 15 kW dual-station induction heater with PID temperature control and two graphite crucibles for different batch sizes
- Reverse-polarity transferred arc plasma system with 7.3 kW arc generator and water-cooled copper anode electrode
- Rotary vane vacuum pump achieving vacuum down to 10e-2 torr, with capacitance diaphragm gauge for precise pressure measurement
- Recirculating water chiller providing stable cooling at 5–30°C with 58 L/min flow rate
- Integrated control panel for synchronized operation of heating, plasma generation, and vacuum systems
- Optional infrared temperature sensor available for monitoring temperatures above 1800°C
Technical Specifications
| Parameter | Specification |
|---|---|
| Vacuum Chamber | Stainless steel, ID Ø315 mm × 315 mm height, water-cooled, quartz observation window Ø120 mm |
| Vacuum Ports | DN160 ISO-K for turbopump, KF40/25 for rough pump, 1/4″ gas inlet and bleed valve, pressure relief valve @ 3 psig |
| Induction Heater | 15 kW, 30–80 kHz, dual station, PID control, 208–240 V AC, 3-phase, 50 A input |
| Induction Coils | Coil 1: Ø72 OD × Ø62 ID × 80 H mm; Coil 2: Ø102 OD × Ø92 ID × 100 H mm |
| Arc Generator | 7.3 kW, 208–240 V AC, 1-phase; DC output 315 A/22.6 V @ 60% duty, 244 A/20 V continuous; HF ignition included |
| Vacuum Pump | 156 L/min rotary vane pump; turbopump optional; capacitance diaphragm gauge included |
| Water Chiller | Recirculating, 58 L/min flow, 5–30°C range, 70 L stainless steel tank, 220 V AC, 3-phase, 7.1 kW |
| Power Requirements | 220 V AC ±10%, three-phase, total 30 kW |
Typical Applications
The VMP-1750 is ideal for metallurgical laboratories and research facilities focused on recovering precious and base metals from oxide slags generated during smelting and refining processes. It supports studies on slag composition, metal extraction efficiency, and process optimization under controlled vacuum and plasma conditions.
Configuration & Operating Notes
The system includes two graphite crucibles and a water-cooled copper cathode electrode integrated into the crucible base. The water-cooled copper anode electrode is inserted into the vacuum chamber and connected to the arc generator. The HF ignition function facilitates plasma arc initiation without direct contact with the slag surface. Optional accessories include an infrared temperature sensor for monitoring temperatures above 1800°C and a turbopump for achieving higher vacuum levels. Proper safety measures should be observed when operating under high vacuum and high-temperature plasma conditions.
