In the electrowinning zinc production process, severe corrosion of inter-cell busbars is a persistent headache for many smelters. This issue not only increases equipment wear and maintenance costs but also leads to higher contact resistance and elevated cell voltage, ultimately resulting in significant energy waste and reduced electrical efficiency.
Solving this problem cannot rely on a single method; it requires comprehensive treatment combining hardware upgrades, process optimization, and daily maintenance. Below is a systematic solution targeting busbar corrosion.
1.Summary and Operational Recommendations
To address severe busbar corrosion, troubleshoot and handle it in the following steps:
|
Step |
Inspection Item |
Recommended Measures |
|
Step 1 |
Check Corrosion Morphology |
If corrosion occurs at connection points, re-grind and apply conductive paste; if overall greening occurs, enhance ventilation and tin plating. |
|
Step 2 |
Test Electrolyte |
Check the concentrations of Cl⁻ and F⁻. If excessively high, consider the waste liquid cyclic chloride removal scheme. |
|
Step 3 |
Evaluate Equipment Load |
If the electrode plate area is >3.2 m² and heating is severe, it is strongly recommended to replace with side-contact water-cooled busbars. |
|
Step 4 |
Daily Maintenance |
Regularly clean surface crystalline salts (creeping liquid), tighten bolts, and eliminate “leakage.” |
Core Insight: Rapid corrosion is often the dual result of “inadequate cell surface maintenance” and “poor solution quality (excessive chlorine and fluoride).” By reducing temperature (water-cooled busbars), isolating corrosion sources (surface treatment/acid mist collection), and recycling (copper mud recovery), this problem can be completely controlled within an acceptable range.
2.Core Cause Diagnosis: Why Does Corrosion Occur So Quickly?
If the busbar corrosion rate is abnormally high, a self-diagnosis should first be conducted. The causes typically fall into the following three categories:
- Harsh Chemical Environment: Excessively high concentrations of chloride ions (Cl⁻)and fluoride ions (F⁻) in the electrolyte. These two elements have strong penetration and corrosiveness, acting as the primary culprits behind busbar deterioration.
- Physical Heating Effect: High contact resistance leads to busbar heating. Elevated temperatures significantly accelerate chemical reaction rates, forming a vicious cycle of “heating – corrosion – further heating.”
- Acid Mist and Operational Management: Severe acid mist emission from cell surfaces, or inadequate on-site maintenance (such as insulation failure and acid dripping), directly erodes the busbars.
3.Hardware Upgrade Solutions: Addressing the Problem at the Structural Level
For severe corrosion issues, adopting new equipment or modifying conductive methods is the most thorough approach.
3.1.Adoption of New Water-Cooled Busbars (PRS Technology Solution)
Traditional busbars struggle to handle working conditions involving high current and large electrode plates.
- Technical Features: This new type of busbar adopts internal water circulation cooling and changes the conductive contact method to left-right side contact (no bottom contact).
- Advantages:
-
- Temperature Reduction and Corrosion Prevention: By lowering the busbar temperature, the rate of chemical corrosion reactions is directly slowed down.
- Increased Contact Area: The left-right contact design significantly expands the effective conductive area, further reducing contact resistance and heating.
- Application Scenario: Specifically designed for large cathodeswith a total area of both sides exceeding 3.2 m² (Big Cathodes with Large Current).
3.2.Transformation of Conductive Method: Elimination of Inter-Cell Busbars
If inter-cell busbars are not used, the corrosion problem is naturally resolved.
- Solution: Adopt the fixture-style platesconductive method.
- Advantage: Directly eliminates the wear and tear link of traditional inter-cell busbars, fundamentally avoiding busbar corrosion.
4.Surface Protection and Process Control: Building a Defense Layer
If rectification is carried out on existing equipment, the following measures are indispensable.
4.1.Physical Surface Protection (Three-Level Protection System)
- Level 1: Plating Protection: The busbars must undergo electroplating treatment. Tin Platingis the most cost-effective choice, providing good chemical stability and conductivity. Silver plating or nickel plating can be selected if the budget permits.
- Level 2: Insulation Shielding: For non-contact surfaces (non-conductive areas) of the busbars, anti-corrosion insulating paint, epoxy resin, or heat-shrinkable tubing must be applied to completely isolate acid mist.
- Level 3: Joint Sealing: Apply conductive pasteor dielectric grease to bolted connections and contact surfaces. This not only reduces contact resistance but also prevents acid from seeping into gaps and causing local crevice corrosion.
4.2.Acid Mist Treatment System
The direct source of corrosion is sulfuric acid mist in the air.
- Installation of Acid Mist Collection System: Add gas collecting hoods and ventilation systems on cell surfaces to extract acid mist at the source.
- Addition of Inhibitors: Add covering balls (plastic balls) or special acid mist inhibitors(surfactants) to the electrolyte to reduce acid mist emission.
Ready to Address Corrosion of Inter-Cell Busbars in EW Zinc?
Don’t let corrosion eat away at your current efficiency and equipment lifespan.
Corrosion of inter-cell busbars is more than just a maintenance issue; it is a “bleeding point” that directly impacts your smelter’s profitability. Whether you are facing heat-induced corrosion from Big Cathodes (>3.2m²) or chemical erosion from High-Chloride electrolytes, PRS has a proven strategy for you.
Tech Upgrade: Discover how PRS patented Side-Contact Water-Cooled Busbars eliminate overheating and minimize acid exposure.
Contact us today. Share your current cell voltage data or cathode dimensions, and we will provide a free diagnostic assessment and ROI analysis for your facility.
