Cyclone Separation of Coal Refuse for Rare Earth Recovery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional methods are inefficient and uneconomical for recovering rare earth elements and titanium from coal refuse due to their low concentration and the fine particle size of coal tailings, which clog processing equipment and require excessive energy and resources.
Innovation Solution
A four-stage cyclone separation process is employed to concentrate and separate rare earth elements and titanium, utilizing cyclone separators to achieve low and high-quality carbon separation, followed by chemical processing to extract and purify these elements.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If conventional mining equipment is used to recover rare earth elements from coal refuse, then the recovery process can be performed, but the process becomes uneconomical due to low element concentration and fine particle size
Solution Approach 1:
The recovery process is divided into multiple sequential stages: classification stage separates particles by size, flotation stage concentrates rare earth elements, and filtration stage produces final concentrate. This segmentation allows each stage to optimize for its specific function, making the overall process economical despite low initial concentrations.
Solution Approach 2:
The classification stage performs preliminary separation of coal refuse into size-based fractions before the flotation stage. This preliminary action removes oversized and undersized particles that would interfere with subsequent processing, concentrating resources on the optimal particle size range containing rare earth elements.
2Ease of operation
If conventional processing equipment is used to handle fine particle size coal tailings, then processing can occur, but equipment clogs and requires excessive energy and resources
Solution Approach 1:
The classification stage uses hydraulic classification where water flow separates particles based on size and density. This hydraulic approach handles fine particles efficiently without mechanical contact that would cause clogging, and consumes less energy than mechanical screening or filtration for fine materials.
Solution Approach 2:
The system replaces mechanical screening and filtration equipment with hydraulic classification and flotation processes. This substitution eliminates mechanical clogging issues associated with fine particles and reduces energy consumption by using fluid dynamics rather than mechanical force for separation.
3Productivity
If conventional recovery equipment is used, then processing can be performed, but separation and extraction become complicated and equipment slows down
Solution Approach 1:
The flotation stage serves multiple functions simultaneously: it concentrates rare earth elements, separates them from gangue minerals, and produces a filterable slurry in one operation. This multi-functionality reduces the number of separate equipment units needed and simplifies the overall process flow while maintaining high productivity.
Solution Approach 2:
The classification and concentration functions are merged into an integrated hydraulic classification-flotation system. Rather than using separate mechanical classifiers followed by separate concentrators, the system combines these functions in a unified hydraulic process that handles fine particles more effectively and reduces equipment complexity.
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
The process efficiently recovers high-quality rare earth elements and titanium with minimal energy and equipment, achieving environmental sustainability and cost-effectiveness by recycling water and reducing the need for ancillary equipment and manpower.
Implementation Method 1
The process employs several cyclone separators staged to recover low and high quality carbon effectively concentrating the elements
Implementation Method 2
The slurry is directed to a second cyclone separator to further separate low quality carbon from high quality carbon
Implementation Method 3
The underflow stream is dewatered through a vibrating screen
Implementation Method 4
The bleed media is directed to a centrifuge which thickens the concentration of rare earth elements and minerals
Data Source
AI summary
A process for concentrating and separating rare earth elements including lithium and titanium from coal refuse. Crushed refuse admixed with water is transferred to a first cyclone separator to divide the admixture into a refuse rich slurry stream and a carbonaceous rich slurry stream. The refuse rich slurry stream is dewatered through a vibrating screen and the water sent to a raw feed sump source. The carbonaceous rich slurry is directed to a second cyclone separator to separate low quality carbon from high quality carbon, the high quality carbon is transferred to a third cyclone separator used to separate the element rich media. The media water is returned to the raw feed sump and the bleed media is directed to a centrifuge which thickens the concentration of rare earth elements and minerals. The effluent is directed to a tailings pond or vacuum press.