In the copper smelting industry, the treatment of flue dust leachate is a critical step for resource recovery and a focal point where environmental compliance and economic efficiency converge. Although the traditional iron replacement process has been used for many years, its drawbacks—such as low recovery efficiency, high impurity content in the product, and the potential generation of highly toxic arsine (AsH₃) gas—make it increasingly unable to meet the modern smelting industry’s requirements for safe, efficient, and clean production.
To address this long-standing industry challenge, Zhengzhou Tiei Extraction Technology Co., Ltd. has developed an innovative copper recovery process specifically for flue dust leachate, based on its self-developed CWL-M series centrifugal extractor. This system achieves a technological transition from “extensive treatment” to “precision purification.”
Limitations of Traditional Processes and Breakthroughs in New Technology
In copper extraction equipment applications, the conventional iron replacement method not only introduces additional iron-ion impurities—thereby increasing the burden on downstream purification—but also poses serious safety risks due to potential arsine formation. In contrast, the centrifugal solvent extraction process developed by Tiei Extraction abandons the metal displacement approach and instead adopts a physicochemical route of multi-stage countercurrent extraction–scrubbing–stripping.
The core of this process lies in the high selectivity of the Lix984/ sulfonated kerosene extraction system for copper ions. Under the strong centrifugal force field generated by the CWL-M centrifugal extractor, efficient separation of copper from impurities such as zinc, lead, and bismuth is achieved. This process eliminates the need for iron powder, fundamentally preventing the generation of toxic gases while significantly improving both the purity and recovery efficiency of copper.
Core Process Flow: Three Steps to Achieve Copper “Purification and Enrichment”
1.High-Efficiency Extraction
The leachate and extractant enter the CWL-M centrifugal extractor, where 1–4 stages of countercurrent extraction are carried out. Copper ions are efficiently transferred into the organic phase, with the extraction rate stably exceeding 98%, while the copper concentration in the raffinate can be reduced to below 0.15 g/L.
2.Deep Scrubbing
The copper-loaded organic phase enters the scrubbing section, where countercurrent washing with clean water is applied to effectively remove entrained or co-extracted impurity ions. This ensures the purity of the organic phase and lays the foundation for producing high-purity downstream products.
3.Precise Stripping
The purified loaded organic phase contacts dilute sulfuric acid in the stripping section, where copper ions are transferred back into the aqueous phase. This produces a high-grade rich copper electrolyte with a concentration of 45–55 g/L, which can be directly sent to the electrowinning circuit for the production of high-quality cathode copper.
Disruptive Advantages: A Win–Win for Economic Efficiency and Environmental Performance
Compared with conventional methods, the centrifugal solvent extraction process demonstrates comprehensive advantages:
1.Ultra-High Recovery Efficiency: Copper recovery increases from below 90% in traditional processes to 98%+, significantly improving resource utilization.
2.High-Purity Product Value: The produced cathode copper contains extremely low impurity levels, reaching quality comparable to Grade A copper, greatly enhancing market value.
3.Optimized Operating Costs: The extractant operates in a closed-loop cycle with very low consumption; the compact and automated process significantly reduces labor and auxiliary material costs.
4.Intrinsic Safety and Environmental Protection: No toxic gas emissions are generated throughout the process, and wastewater composition is simpler and easier to treat, enabling greener smelting operations.
5.Compact and Flexible Footprint: The modular CWL-M centrifugal extractor offers high stage efficiency and small footprint, making it especially suitable for retrofitting and upgrading existing production lines.
Proven in Practice: Successful Transformation from Data to Benefits
This technology has already been industrially applied in several large-scale smelting enterprises in China. For example, one plant treated a leachate containing 6.97 g/L of copper and achieved a 98.8% copper recovery rate after three-stage extraction. Another plant processed a higher-concentration solution containing 12.76 g/L of copper. Through four-stage extraction, the copper recovery rate still reached 98.5%, while producing a rich copper solution with a concentration of 53.85 g/L. These results fully demonstrate the strong adaptability of the process to feed solutions with varying copper concentrations.
With the continuous advancement of resource recycling requirements and environmental regulations, the high-efficiency recovery solution centered on the CWL-M centrifugal extractor is becoming a strategic choice for copper smelting enterprises seeking cost reduction, efficiency improvement, and green transformation. Zhengzhou Tiei Extraction Technology Co., Ltd. provides customers with a complete solution covering process design, core equipment supply, and system integration, helping enterprises capture new opportunities in the field of resource recycling.
Email: sales@tieiextraction.com
Whatsapp: +86 19069612820
