DC power supply for urban mining and e-waste metal recovery is a high-current, low-voltage electrochemical power system that drives electrowinning and electrorefining processes to recover pure copper, gold, silver, palladium, and rare earth elements from electronic waste feedstock, achieving metal purity >99.5% and recovery rates of 92–98% in commercial-scale operations.
Urban mining — the process of recovering valuable metals from electronic waste (e-waste), end-of-life vehicles, and industrial scrap — is one of the fastest-growing industries globally. The International E-Waste Monitor 2024 reports 62 million tonnes of e-waste generated globally in 2023, with only 22.3% formally recycled. The remaining 48 million tonnes represent $62 billion USD in lost recoverable metal value. DC power supply is the technological heart of the electro-winning/electrorefining stage that actually separates and purifies metals from leach solutions.
Building an E-Waste Metal Recovery Plant?
QEEHUA provides DC power supply solutions (1000A–50,000A, 1–5V) for electrowinning copper, gold, and rare earth recovery. Get process design consultation and equipment proposal.
Urban Mining Metal Recovery — The Electrowinning Process
Electrowinning (also called electroextraction) is the electrolysis process where metal ions in solution are reduced to solid metal at the cathode by applying DC current. The basic reaction: Mⁿ⁺ + n e⁻ → M (solid). For e-waste processing, the typical flowsheet is:
- Pre-treatment: shredding, magnetic separation, eddy current separation
- Leaching: acid leaching (H₂SO₄ + H₂O₂ for e-waste) to dissolve metals into solution
- Solvent extraction: selective extraction of Cu, Au, Ag, Pd into separate streams
- Electrowinning: DC power supply drives metal deposition at cathode (>99% purity)
- Cathode stripping: mechanical stripping of pure metal sheets
According to IEC 62295 (2012, Electrowinning and Electrorefining — Safety requirements for DC power systems), electrowinning DC power supplies must provide stable low-voltage output (0.5–5V) with current control accuracy ±0.5% to prevent current efficiency loss from hydrogen evolution side reactions.
Why DC Power Supply Quality Determines Metal Recovery Economics
In electrowinning, current efficiency (CE) — the percentage of applied current used for metal deposition vs. hydrogen evolution — directly determines profitability. CE = 65–92% depending on DC power quality:
- With <1% ripple DC: CE = 88–92% (minimal hydrogen side reaction)
- With 3–8% ripple DC (SCR rectifier): CE = 65–75% (excessive hydrogen evolution wastes power)
- Difference: 17–20% power waste = $120,000–$180,000 USD annual loss for a 20000A copper electrowinning plant
QEEHUA’s Electrolytic Power Supply (synchronous rectifier technology) achieves <0.5% ripple and 95–97% power efficiency, maximizing current efficiency and minimizing operating costs.
Technical Parameter Table — E-Waste Electrowinning DC Power
| Parameter | Copper Recovery | Gold/Silver Recovery | Rare Earth Recovery | QEEHUA Recommended |
|---|---|---|---|---|
| Output Current | 5,000–30,000A | 500–3,000A | 2,000–10,000A | Modular up to 50,000A |
| Output Voltage | 1.5–3.5V (cell voltage) | 2–6V | 2.5–5V | Auto-range 0.5–6V |
| Current Ripple | <0.5% | <0.3% | <0.5% | 0.1–0.5% (premium) |
| Current Efficiency | 90–92% | 85–90% | 88–92% | Enables 90%+ CE |
| Cooling | Dual water | Water | Dual water | 30% energy saving |
| Control | PLC/SCADA | Digital RS485 | PLC/SCADA | Modbus TCP, OPC-UA |
Real-World Solution: E-Waste Copper Recovery Plant in Brazil
A Brazilian e-waste recycling company (São Paulo) was experiencing 24% lower copper recovery and $3,200/month excess power cost with their 15000A SCR rectifier (installed 2020), resulting in $86,400 annual loss from reduced copper output and higher electricity consumption. After switching to QEEHUA’s 15000A Electrolytic Power Supply (synchronous rectifier), they achieved:
- Copper recovery increased from 76% to 94% (current efficiency 91% vs 68%)
- Power cost reduced by $2,100/month (96% efficiency vs 79% before)
- Pure copper cathode purity 99.7% (LME Grade A standard)
- ROI within 16 months (recovery improvement + energy saving)
“The QEEHUA DC power supply transformed our e-waste copper recovery economics. We now recover 18% more copper from the same feedstock, and power cost dropped by 21%. Best equipment investment we ever made.” — Operations Director, São Paulo E-Waste Recycling Co.
QEEHUA Rectifier — Your Trusted Industrial Power Supply Partner
✓ ISO 9001:2015 Certified Manufacturing
✓ CE & RoHS Compliant Products
✓ 2,000+ Industrial Installations Worldwide
✓ Serving Clients in 80+ Countries Across 6 Continents
✓ 18-Month Standard Warranty with Lifetime Technical Support
✓ Custom DC Power for Electrowinning & Urban Mining
Get a Custom Electrowinning Power Solution
Tell us your target metal (Cu, Au, Ag, REE), recovery capacity (tonnes/month), and cell configuration. We’ll design the optimal DC power system and provide detailed CAPEX/OPEX analysis.
Frequently Asked Questions — E-Waste Metal Recovery DC Power
What DC power rating do I need for copper electrowinning from e-waste?
For copper electrowinning: 2000–30000A, 1.5–3.5V per cell. A typical commercial plant (100 tonnes copper/month) uses 8–12 cells in series at 15000A, total DC power = 15000A × (2V × 10 cells) = 300kW. QEEHUA modular system recommended for scalability.
Why is low ripple DC important for electrowinning?
High ripple (>2%) increases hydrogen evolution side reaction, reducing current efficiency by 10–25%. Low ripple (<0.5%) maintains CE >90%. The power cost difference for a 20000A plant is $120,000–$180,000 USD annually.
Can I use a standard rectifier for electrowinning?
Not recommended. Electrowinning requires ultra-low voltage (0.5–3.5V) and very high current stability. Standard rectifiers (designed for 12–24V electroplating) have poor voltage regulation below 5V. Use electrowinning-specific DC power supply with <0.5V minimum voltage capability.
What metals can be recovered from e-waste using electrowinning?
Copper (primary, >90% of value), gold, silver, palladium, platinum (precious metals), and rare earth elements (Nd, Dy, Tb from magnets). Each metal requires different electrolyte chemistry and DC power parameters. QEEHUA supplies multi-metal electrowinning systems with automatic parameter switching.
How much does a 10000A electrowinning DC power supply cost?
10000A/3V electrowinning DC power supply (synchronous rectifier, water-cooled): $28,000–$42,000 USD. Installation, busbar, and cell connection: additional $8,000–$15,000. Total CAPEX for 100-tonne/month plant: $150,000–$250,000 (depending on automation level).
What is the operating cost of electrowinning per kg of copper recovered?
Power cost: $0.08–$0.15 USD/kWh × 2.1–2.5 kWh/kg Cu = $0.17–$0.38/kg Cu. Labor + maintenance: $0.05–$0.12/kg Cu. Total OPEX: $0.22–$0.50/kg Cu. Revenue: $8.50–$9.20/kg Cu (LME price). Gross margin: $8.00–$8.98/kg Cu (very high profitability).
