The non-ferrous metals industry has long been a cornerstone of
global industrial development, and zinc remains one of its most
critical commodities. Zinc’s applications span galvanizing steel,
die-casting alloys, and battery production, making efficient
processing vital for sectors like construction, automotive, and
renewable energy. However, traditional zinc processing methods
face challenges such as energy inefficiency, environmental concerns,
and operational variability. The integration of automation technologies
is transforming this landscape, enhancing productivity, sustainability,
and safety. This article explores how automation is reshaping zinc
processing, focusing on key applications, benefits, and future trends.
1. The Zinc Processing Workflow:
Challenges and Opportunities
Zinc production involves multiple stages, including ore concentration,
roasting, leaching, purification, and electrolysis. Each step presents
unique challenges:
Ore Sorting and Concentration: Manual sorting of zinc ores
(e.g., sphalerite) is labor-intensive and prone to errors, leading
to suboptimal recovery rates.
Roasting: Temperature control in roasting furnaces directly
impacts zinc oxide quality. Inconsistent heat distribution can
result in energy waste or incomplete conversion.
Leaching and Purification: Chemical processes require precise
pH and temperature adjustments. Human error in monitoring
can cause impurities, reducing final product purity.
Electrolysis: Maintaining stable current density and electrolyte
composition is critical; fluctuations reduce cathode zinc quality.
These pain points highlight the need for automation to standardize
processes, reduce waste, and improve yield.
2. Automation Technologies in
Zinc Processing
2.1 Sensor-Based Ore Sorting
Modern zinc processing plants employ sensor-based ore sorting systems
using X-ray fluorescence (XRF), near-infrared (NIR) spectroscopy, and
machine vision. These technologies analyze ore composition in real time,
enabling automated separation of high-grade zinc ores from waste rock.
For example, Tomra’s XRT sensors have been deployed in mines to
increase ore recovery rates by 15–20%, reducing reliance on manual labor.
2.2 Advanced Process Control (APC) Systems
APC systems optimize critical parameters in roasting and leaching. For instance:
Roasting Automation: Machine learning algorithms adjust furnace
temperatures based on real-time gas composition data from
laser-based analyzers. This ensures optimal zinc oxide conversion
while minimizing SO₂ emissions.
Leaching Optimization: pH and temperature sensors feed data to
programmable logic controllers (PLCs), which autonomously adjust
reagent dosing. At the Skorpion Zinc refinery in Namibia, APC
reduced acid consumption by 12% and improved zinc recovery by 8%.
2.3 Robotics in Electrolysis
Electrolytic zinc refining requires precise handling of cathodes and anodes.
Collaborative robots (cobots) now perform tasks such as stripping zinc
deposits from cathodes, reducing human exposure to acidic environments.
ABB’s robotic solutions, integrated with vision systems, have cut downtime
by 30% in pilot installations.
2.4 Digital Twin Technology
Digital twins—virtual replicas of physical processes—are gaining traction.
By simulating roasting or leaching dynamics, engineers predict equipment
wear, optimize energy use, and test process modifications. Boliden’s Kokkola
zinc plant in Finland reported a 10% reduction in energy costs after
implementing a digital twin for its roasting circuit.
2.5 IoT and Predictive Maintenance
Wireless IoT sensors monitor equipment health (e.g., pump vibrations, motor
temperatures) in real time. Predictive analytics platforms like GE’s Predix alert
operators to potential failures before they occur. At Hindustan Zinc’s smelters,
this approach reduced unplanned downtime by 25% and extended equipment lifespan by 18%.
3. Benefits of Automation in Zinc
Processing
3.1 Enhanced Efficiency and Yield
Automation minimizes human error and ensures consistent process
parameters. For example, automated electrolyte circulation systems in
electrolysis maintain uniform zinc deposition, boosting cathode purity
from 99.5% to 99.95%. This improvement directly translates to higher
market value.
3.2 Energy and Resource Savings
Smart energy management systems in roasting furnaces have cut fuel
consumption by 20% at Nyrstar’s Auby plant. Similarly, automated water
recycling in leaching circuits reduces freshwater usage by up to 40%,
aligning with circular economy goals.
3.3 Improved Safety
Automation reduces worker exposure to hazardous environments.
Remote-controlled drones inspect sulfuric acid storage tanks, while
exoskeletons assist in manual tasks, lowering injury rates by 50% in trials.
3.4 Environmental Compliance
Continuous emission monitoring systems (CEMS) ensure compliance with
regulations like the EU’s Industrial Emissions Directive. Automated
scrubbers adjust SO₂ capture rates in real time, cutting emissions by
30% at Glencore’s Canadian operations.
4. Challenges and Future Directions
4.1 Integration Costs
The upfront cost of automation remains a barrier, particularly for smaller
producers. Modular, scalable solutions are emerging to address this. For
instance, cloud-based APC systems now offer pay-per-use models.
4.2 Workforce Adaptation
Reskilling workers to manage automated systems is critical. Companies
like Teck Resources have partnered with vocational institutes to develop
AI-driven training platforms for operators.
4.3 Cybersecurity Risks
Connected systems are vulnerable to cyberattacks. Blockchain-based
security protocols and air-gapped networks are being tested to
protect sensitive data.
4.4 Next-Gen Innovations
Future advancements may include:
AI-Driven Process Optimization: Deep learning models could
predict zinc prices and adjust production schedules autonomously.
Hydrogen-Based Roasting: Automated hydrogen furnaces may
replace coal-fired systems, reducing carbon footprints.
Autonomous Mining Fleets: Self-driving trucks and drills could
integrate with processing plants for end-to-end automation.
5. Conclusion
Automation is no longer optional in zinc processing—it is a strategic
imperative. By leveraging sensors, robotics, and AI, the industry is
achieving unprecedented levels of efficiency, sustainability, and safety.
While challenges like cost and workforce adaptation persist, collaborative
efforts between tech providers and manufacturers are paving the way
for a smarter, greener future. As zinc demand grows alongside renewable
energy and electric vehicle markets, automation will remain the linchpin
of competitive advantage in the non-ferrous metals sector.