An Electrolytic Copper Refining Plant (tankhouse) serves as the critical terminal stage in modern pyrometallurgical processing, directly bridging rough smelting with high-value end-market applications. As global demand for secondary copper recycling and pyrometallurgical efficiency accelerates, pyrometallurgy has become the dominant path for processing crude blister copper and complex copper scrap. However, thermal refining alone cannot eliminate trace harmful impurities like arsenic, bismuth, or antimony. The electrolytic tankhouse performs the essential final separation, taking cast copper anodes and electro-refining them in specialized cells to consistently achieve LME Grade A high-purity copper cathodes (≥99.99% Cu).
1. Overview: Electrolytic Copper Refining Plant - From Cast Anode to LME Grade A (99.99%) Cathode
With pyrometallurgical smelting established as the industry-standard approach for processing secondary copper scrap and concentrate, the electrolytic refining tankhouse acts as the ultimate quality gatekeeper. Cast copper anodes produced from anode furnaces are electrochemically dissolved and redeposited in high-grade cells. Through precise control of electrolyte chemistry, current density, and circulation, our turnkey refining plants transform commercial-grade anode copper into LME Grade A cathodes with a purity exceeding 99.99%, ensuring full compliance for high-conductivity wire, cable, and advanced industrial manufacturing.
- Cathode copper produced from copper scrap, with the tested copper purity reaching 99.99%.
2. Process Flow
Based on our complete Electrolysis Process Flow diagram, the plant operates through four tightly integrated loops:
2.1 Main Electrolysis & Cathode Harvesting
- Cast anodes from the smelter undergo preparation and spacing verification before being loaded via crane into the cells alongside reusable stainless steel cathode blank plates.
- After a 10–12 day cathode cycle, high-purity copper cathodes are harvested, washed in a dedicated tank, and stripped via an automated/semi-automated stripping machine. The final copper cathodes (≥99.99%) are bundled for sale, while blank plates return to the cells.
- Anodes run on a 20–24 day cycle, leaving scrap anodes that are manually washed, stacked, and returned to the smelter for re-melting.
2.2 Electrolyte Heating & Reagent Management
- Concentrated Hydrochloric Acid (37% HCl) and Sulfuric Acid (98% H₂SO₄) are delivered, pumped into storage tanks, and precisely dosed into dilution/reagent tanks.
- Organic additives (glue and thiourea) are dissolved and metered into the main circulation tank to maintain smooth crystal growth on cathode surfaces.
- The electrolyte is continuously driven by horizontal circulation pumps through steam-operated plate heat exchangers (62–65°C) into the bottom of the cells and overflows back to the circulation tank.
2.3 Anode Slime Recovery
- Heavily loaded electrolyte at the bottom of the cells is drained to a decant tank.
- Decanted slime and sludge are pumped to a 30 m² box filter press.
- The resulting dry slime cake is sent downstream for precious metal (Gold, Silver, Platinum group) extraction, while the filtrate is recycled back to the main circulation system.
2.4 Multi-Stage Electrolyte Bleed & Purification (De-Cu Systems)
- 1st De-Cu Stage: Removes excess copper when impurity levels are low to produce standard cathode copper.
- 2nd De-Cu Stage: Co-deposits copper along with arsenic, bismuth, and antimony (2–5 g/L Cu²⁺). Note: If copper content is moderate but impurity levels are excessively high, this step is dynamically bypassed.
- 3rd De-Cu Stage: Performs deep copper removal, precipitating heavy metal sludge directly to the slime processing line.
- Nickel Recovery Line: When nickel concentration in the circulating electrolyte exceeds 15 g/L, the bleed stream is directed to an evaporative/crystallization system to recover crude nickel sulfate (NiSO₄).
3. Core Equipment Specifications for 5,000TPA
| Equipment Category | Specification / Model | Key Operational Function |
|---|---|---|
| Polymer Concrete Electrolytic Cells | 4000×1170×1400/1600 mm | High-rigidity, acid-proof cells housing 36 cathodes and 37 anodes per tank. |
| Rectifier System | 20V/24kA DC Rectifier | Powers cells up to 330 A/m² current density with minimal voltage ripple. |
| Anode Preparation & Reshaping Machine | 200 pcs/h Capacity | Automated lug pressing, thickness measurement, milling, and vertical alignment. |
| Residual Anode Washing Line | 300 pcs/h Capacity | Cleans anode scrap prior to returning to the smelting furnace. |
| Electrolyte Circulation Pumps | 70 m³/h Flow, 25 m Head (VFD) | Variable-frequency direct pumping, eliminating energy-intensive overhead tanks. |
| Heat Exchangers | SMO254 Anti-Corrosion Alloy Plate Heat Exchangers | Steam-heated system maintaining electrolyte temperatures at 62–65°C. |
| Filter Press System | 30 m² Box Filter Press | Dual-function unit handling both anode slime dewatering and electrolyte clarification. |
| Acid Mist Handling & Safety System | Negative-pressure hoods & Scrubber Interlock | Fume extraction interlocking directly with the rectifier for automatic shutdown during fault events. |
4. Why Choose PRS: Our Core Advantages & Value Add
PRS provides mature and proven Flow Process support to guarantee your plant produces LME Grade A copper cathodes consistently.
- Proven Megaproject Experience & International Documentation Standards Having participated in large-scale copper refinery projects worldwide, we bring rigorous Quality Control (QC) systems and internationally standardized engineering documentation to your project, simplifying local permitting and operational audits.
- On-Site Operational Support (3-Month Trial Operation Team) We do not just deliver hardware; we send our seasoned operations team to your site for up to 3 months of trial operation, helping your team master chemical bath tuning, current efficiency control, and troubleshooting until stable production is achieved.
- Rapid Project Delivery & Short Lead Time Our streamlined manufacturing schedules and modular equipment supply chain significantly shorten lead times, allowing you to get your tankhouse operational and generating cash flow ahead of schedule.
- Extended 24-Month Warranty on Cathode Plates To demonstrate absolute confidence in our manufacturing quality and metallurgy, we extend the standard warranty on our stainless steel cathode plates to 24 months, protecting your investment long after commissioning.
5. Flexible Layout & Modular Turnkey Execution
Optimized Plant Layout: Designed for a compact single-span main building (67.5 m×15 m) with an auxiliary span (12 m), delivering 5,000 t/a capacity within just 1,822.5 m².
Modular Scalability: Structured in pre-engineered cell groups (e.g., 2 groups of 19 cells), allowing your facility to expand seamlessly from 3,000 t/a to 5,000 t/a and beyond by adding power modules and cell blocks.
Full EPC Execution: Complete turnkey delivery covering process engineering, procurement, civil/structural alignment, installation supervision, and chemical commissioning.
