As the core equipment in the non-ferrous metallurgical industry,
electrowinning cells are widely used in the electrolytic refining and
deposition process of copper, aluminium, zinc, nickel and other
metals. The quality of its installation is directly related to the stability
of the production line, the level of energy consumption and metal
recovery rate. With the increasingly stringent global requirements
for cleaner production and efficient use of resources, the scientific
and standardised installation process of electrolysis tanks has become
the key for enterprises to achieve cost reduction and increase
efficiency, and break through the bottleneck of environmental
protection. This article will provide a set of systematic electrolyzer
installation guidelines for the industry from the dimensions of
equipment selection, installation steps, commissioning optimisation
and maintenance strategies.
First, the core role of electrowinning cell in the
non-ferrous industry
Electrolysis cell realises the purification and recovery of metal through
electrochemical reaction, which is the ‘core reactor’ of hydrometallurgical
process. For example, in copper electrolytic refining, after the dissolution
of the crude copper anode, copper ions are deposited at the cathode as
high-purity electrolytic copper; in aluminium electrolysis, alumina is
decomposed into liquid aluminium and oxygen. However, improperly
installed electrolysers can lead to the following problems:
Reduced current efficiency: uneven spacing of the plates or poor contact,
triggering localised overheating or uneven metal deposition.
Reduced equipment life: corrosion of the tank and sealing failures lead to
electrolyte leakage, increasing maintenance costs.
Safety hazards: electrical short circuits or harmful gas accumulation threaten
personnel safety.
Therefore, standardised installation is the basis for ensuring efficient and
safe operation of the electrolysis process.
Second, the key preparatory work before the
installation of electrolytic cell
1. Equipment selection and parameter matching
Capacity design: Determine the number and size of electrowinning cells
according to the average daily metal production (e.g. 100,000 tonnes of
copper cathode per year), and the volume of a single tank is usually 5~20m³.
Material selection:
Tank body: acid/alkali corrosion-resistant materials (polypropylene PP,
glass FRP, titanium alloy).
Plate: stainless steel or titanium plate for cathode, lead alloy, iridium-plated
titanium mesh for anode.
Electrical configuration: DC power supply voltage range (26V), current
density (200800A/m²) need to match the process.
2. Site planning and foundation construction
Space layout:
Tank spacing ≥1.2m, reserved access for maintenance;
Auxiliary equipment such as electrolyte storage tanks, circulating pumps,
power supply cabinets, etc. are arranged close to each other to reduce
pipeline pressure loss.
Foundation requirements:
Concrete foundation load-bearing ≥ 1.5 times the full load weight of the
equipment, leveling error ≤ 3mm/m;
Pre-buried anticorrosive ground bolts or channel steel bracket to prevent
displacement of the tank.
3. Safety and environmental protection preparation
Ventilation system: install explosion-proof fan and gas detector (monitoring
Cl₂, SO₂, etc.), the number of air changes ≥ 8 times / hour.
Anti-leakage measures: lay acid-resistant epoxy coating on the ground, set up
emergency collection trench and neutralisation tank.
Third, electrowinning cell installation steps
1. Tank assembly and sealing test
Segmented tank splicing:
Use Viton gaskets and bolts to fix the joints, with torque applied according
to specifications (e.g. 30~50N-m);
Apply acid-resistant sealant (e.g. silicone adhesive) to the joints and leave
to cure for 24 hours.
Sealability test:
Fill the tank with water to full, pressurise to 1.5 times the working pressure,
hold pressure for 2 hours without leakage as qualified.
2. Installation of pole plate and conductive system
Arrangement of pole plate:
Adopt ‘anode-cathode-anode’ alternating layout, the error of pole spacing
≤ ± 2mm (copper electrolysis is usually 90~110mm);
The deviation of verticality of pole plate is <1mm/m to avoid uneven deposition
caused by edge effect.
Conductive pole connection:
The cross-sectional area of copper or aluminium rows is calculated according
to the current density (e.g. 1000A needs ≥240mm²);
The contact surface is polished and coated with conductive paste, and the bolt
tightening torque is uniform (e.g. 20~30N-m).
3. Electrolyte circulation system installation
Piping and pump valve configuration:
UPVC/PPR pipeline slope ≥1% to avoid air resistance;
Corrosion-resistant magnetic pump flow to match the circulating demand
(such as 20~100m³/h), import and export with Y-type filter.
Temperature control:
Install titanium heat exchanger or steam coil to maintain constant electrolyte
temperature (copper electrolysis is usually 50~65℃).
4. Electrical system and automation integration
DC power supply wiring:
Positive and negative cables are marked in different colours (red for positive,
blue for negative), and water-cooled cables are used to reduce resistance heat;
Configuration of shunt and Hall sensor, real-time monitoring of each slot current.
Automation control:
PLC system integrates temperature, liquid level and pH sensors to achieve
automatic replenishment and alarm;
Support remote monitoring and data export to optimise process parameters.
Commissioning and process optimisation strategy
1. No-load test and parameter calibration
Insulation test: use 1000V megohmmeter to measure the insulation
resistance of the pole plate to the ground > 10MΩ.
Current distribution test: energise to 30% of the rated voltage, measure
the voltage drop between each pole plate, and adjust the pole spacing
if the difference is >5%.
2. Load operation and process adjustment
Electrolyte injection:
Slowly fill the electrolyte until the liquid level is 50mm higher than the top
of the pole plate, turn on the circulating pump to eliminate air bubbles;
Initial current density is set at 50% of the design value, gradually
increase to full load after 24 hours.
Additive management:
Add gelatin (0.1~0.5g/L) to inhibit the growth of dendrite for copper electrolysis;
Zinc electrolysis add antimony salt (0.05~0.2g/L) to enhance the
densification of deposition.
3. Energy efficiency and environmental acceptance
Current efficiency calculation: actual metal production/theoretical
value×100%, target ≥92%.
Waste liquid treatment:
Heavy metal-containing waste liquid can be discharged only after
neutralisation and precipitation, ion adsorption, pH 6~9 and heavy
metal concentration <1mg/L.
V. Operation and Maintenance Management
and Troubleshooting
1. Daily maintenance points
Tank cleaning: clean the anode mud at the bottom of the tank every week
to prevent short circuit;
Maintenance of pole plate: take out the pole plate every cycle (10~15 days),
mechanically scrape off the deposits and check the corrosion;
Seal check: test the sealing of flange and interface every month, replace
the aging gasket.
2. Common troubleshooting
Abnormal electrolyte temperature: check the heat exchanger valve or
temperature control system;
Large current fluctuations: clean the contact surface of the conductive
rod and test the cable joints for oxidation;
Tank leakage: immediately shut down to empty the electrolyte, repair
or replace the damaged parts.
Sixth, the future trend: intelligent and
sustainable development
Digital twin technology: collect data in real time through sensors, build
virtual models to predict tank life and energy bottlenecks.
Green process upgrade:
Develop low energy consumption ion membrane electrolyser to replace
the traditional high pollution process;
Coupled PV/wind power DC power supply to reduce carbon emissions.
Material innovation: nano-coated pole plate to extend service life,
graphene composite material to improve conductive efficiency.
Conclusion
Efficient installation and fine management of electrolysis tanks is the core
link to promote non-ferrous enterprises to achieve green transformation
and enhance international competitiveness. With the breakthrough of
intelligent technology and new material application, the electrolysis process
is evolving towards a more efficient and environmentally friendly direction.
Enterprises need to strictly follow the installation specifications, establish a
full life cycle management system, and actively embrace technological
innovation in order to be invincible in the dual challenges of resource
constraints and environmental regulations.