Electro-refining Cell for Metal Purity and Energy Efficiency
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current metal refining processes for mixtures of conductive particles, such as copper, zinc, and noble metals, are inefficient in terms of energy consumption and produce environment-polluting residues, with existing hydrometallurgical methods being non-versatile and requiring high energy and large feed streams, while pyrometallurgical processes have high energy consumption and lower metal value due to the presence of less noble metals.
Innovation Solution
A process involving selective leaching to separate less noble metals from the metal of interest, followed by electro-refining to produce a concentrated metal stream, which reduces energy consumption and allows for high-purity metal recovery without the need for casting anodes or adding virgin metals, using a vertically placed anode and cathode setup for efficient plating.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If pyrometallurgical processes are used for metal refining, then metal separation and upgrading can be achieved, but energy consumption is high and large feed streams are required
Solution Approach 1:
The patent replaces pyrometallurgical (thermal) processes with electrochemical processes. Instead of using high-temperature melting and oxidation, the invention uses electro-refining cells where electric current drives the separation and purification of metals from conductive particle mixtures, thereby eliminating the need for high energy consumption associated with thermal processing
Solution Approach 2:
The patent changes the fundamental processing parameters from high-temperature thermal conditions to ambient or mild temperature electrochemical conditions. By controlling electrical parameters (current, voltage, electrolyte composition) rather than thermal parameters, the process achieves metal separation with dramatically reduced energy input
2Manufacturing precision
If existing hydrometallurgical methods are used to purify valuable metals, then metal purification can be achieved, but less noble metals are not separated and build-up in electrolyte occurs
Solution Approach 1:
The patent segments the metal separation process into distinct electrochemical stages. First, valuable metals (copper, zinc, lead) are dissolved from conductive particles into the electrolyte. Then, through controlled electro-refining, metals are deposited onto cathodes in order of their electrochemical activity, achieving sequential separation of multiple metal types rather than simultaneous mixed recovery
Solution Approach 2:
The electro-refining cell serves multiple functions: it dissolves metals from particles, separates them by electrochemical potential, deposits purified metals on cathodes, and regenerates the electrolyte. This single apparatus handles both purification and separation of multiple metal types, making the process versatile for different feed compositions
3Manufacturing precision
If leaching and electrowinning processes are used, then valuable metals can be purified from mixtures, but energy efficiency is low and liquid waste stream is produced
Solution Approach 1:
The patent implements continuous electro-refining where the electrolyte circulates continuously between the dissolution zone and the deposition zone. Metals are continuously dissolved from conductive particles and simultaneously deposited on cathodes, eliminating the batch processing interruptions and redundant steps in traditional leaching-electrowinning sequences, thereby improving energy efficiency
Solution Approach 2:
The electrolyte serves multiple purposes simultaneously: it acts as the medium for metal dissolution, the source of metal ions for deposition, and the circulating fluid that transports metals through the system. The process uses its own electrolyte solution for all critical functions, eliminating the need for separate washing, filtering, and waste treatment streams
4Manufacturing precision
If conventional electrochemical decomposition is used, then metal purification can be achieved, but the method is not versatile for less noble metals
Solution Approach 1:
The patent employs dynamic control of electrochemical parameters (applied potential, current density, electrolyte flow rate) to adapt the process to different metal compositions in the feed. By adjusting these parameters, the system can selectively dissolve and deposit different metals based on their electrochemical properties, making the method versatile for various conductive particle mixtures containing different ratios of copper, zinc, lead, and other metals
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This process achieves metal recovery with purity exceeding 95 wt.%, reduces energy consumption, and minimizes environmental pollution by concentrating metals directly from a conductive stream, making it suitable for smaller feed streams and preventing distant transport, while allowing for further refining of remaining metals.
Implementation Method 1
a) - feeding said mixture of conductive particles to a separation unit, wherein a less noble metal is separated from the metal of interest by selective leaching
Implementation Method 2
b) - followed by a step of separating the metal of interest from said conductive stream by electro-refining
Implementation Method 3
the metal of interest can be plated onto cathodes using an electrical current whereby said conductive stream comprising the metal of interest is used as anode
Data Source
Figure 1~2
AI summary
The invention is directed to a process and apparatus for metal refining, in particular for refining a mixture of conductive particles, such as heavy non- ferrous particles. In accordance with the invention a feed containing a mixture of conductive particles is fed to a dissolution unit, wherein the less noble metal is separated from at least one metal of interest in the presence of one or more acids or complexing agents, thus producing a stream comprising at least one concentrated less noble metal and producing a conductive stream containing at least one metal of interest. Said conductive stream is then fed to a refining unit, wherein said conductive stream is separated in a stream of concentrated metal(s) of interest and a stream of concentrated conductive particles.