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Published on: February 21, 2017
Processing fine stainless-steel slag using spiral concentration.
1Energy and Mineral Engineering, The Pennsylvania State University, University Park, Pennsylvania, USA.
Summary
Spiral concentration effectively processed fine stainless-steel slag, yielding a high-metal product. However, it was ineffective for aggregate recovery, requiring reprocessing or further slag liberation for optimal results.
Area of Science:
- Metallurgical Engineering
- Mineral Processing
Background:
- Stainless-steel slag presents a challenge for metal recovery due to its fine particle size (-1 mm).
- Efficiently separating valuable metals from slag is crucial for resource sustainability and waste reduction.
Purpose of the Study:
- To evaluate the effectiveness of spiral concentration for processing fine stainless-steel slag.
- To determine the feasibility of producing high-metal and low-metal aggregate products.
- To investigate the impact of operating variables, specifically feed solids concentration, on spiral concentrator performance.
Main Methods:
- Conducted separation tests using five- and seven-turn spiral concentrators on stainless-steel slag.
- Characterized raw slag and spiral products for size and metal distributions.
- Varied feed solids concentration from 15 to 30 kg/min to assess its effect on spiral performance.
Main Results:
- Achieved a high-quality metal fraction (95% metal) using a five-turn spiral, albeit with low metal recovery.
- Spiral concentrators were ineffective in concentrating the aggregate fraction.
- Feed solids concentration (below 35% by weight) showed no significant impact on product quality or metal recovery.
Conclusions:
- Spiral concentration can produce a high-grade metal product from stainless-steel slag under specific conditions.
- Reprocessing or enhanced liberation techniques are necessary to improve metal recovery and create a low-metal aggregate product.
- Further optimization is needed for efficient dual-product separation from fine stainless-steel slag.
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