Mineral Processing
Rim Amata; Mohamed Bounouala; Ashraf Alsafasfeh; Amar Amata; Sofiane Bouabdallah
Abstract
The Djebel Onk region of Algeria faces a significant environmental concern, related to phosphate mining waste. Although these mining tailings contain relatively low quantities of valuable minerals, they still include up to 25% P₂O₅ in the particle size range of 0.25-1 mm (-1-+0.25), suggesting the ...
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The Djebel Onk region of Algeria faces a significant environmental concern, related to phosphate mining waste. Although these mining tailings contain relatively low quantities of valuable minerals, they still include up to 25% P₂O₅ in the particle size range of 0.25-1 mm (-1-+0.25), suggesting the potential for recovery and reuse. This research, based on the Bir El Ater area, explores the methods to recover phosphate-rich minerals, optimizing their reuse. Two techniques were explored: calcination, a heat treatment altering mineral chemistry, and electrostatic separation, which uses the electrical properties to separate minerals. The black phosphate tailings collected from the curved grids of wet processing were subjected to detailed analysis using Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), and X-Ray Fluorescence (XRF), to examine their mineralogical and chemical properties. The results showed a notable improvement in the P₂O₅ concentration, with electrostatic separation reaching a 30.03% content and an 89% recovery rate, while calcination achieved the 30.91% content with a 91% recovery rate. These results highlight the effectiveness of both methods in recovering phosphate from mining tailings, contributing to a better waste management, a more efficient resource use, and a reduced environmental footprint. They also suggest sustainable recovery pathways, especially for the regions facing water scarcity, where flotation is impractical. With the ability to achieve high recovery rates without chemical inputs, calcination and electrostatic separation stand out as environmentally sustainable options for global phosphate beneficiation.
Mineral Processing
Ashraf Alsafasfeh; Anum Razzaq; Abeer Sajid; Maryam Nazir; Muhammad Badar Hayat; Mirza Zaid
Abstract
Palygorskite (PAL), also known as attapulgite, is a clay mineral prized for its nanorod-like silicate structure and fibrous morphology. The traditional PAL purification methods often involve wet gravity separation techniques such as sedimentation and screening, which require significant water usage and ...
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Palygorskite (PAL), also known as attapulgite, is a clay mineral prized for its nanorod-like silicate structure and fibrous morphology. The traditional PAL purification methods often involve wet gravity separation techniques such as sedimentation and screening, which require significant water usage and pose sustainability challenges, especially in the water-scarce regions. This work introduces a novel, environmentally sustainable dry beneficiation method for PAL. A large PAL sample with 41.7% content and 10% moisture was crushed, ground using a pin mill, and classified into three particle size fractions:-0.088 mm + 0.066 mm, -0.066mm +0.044 mm, and -0.044 mm. These fractions were treated with an air classifier. A Box-Behnken experimental design was employed to investigate the effects of particle size, shutter opening, and motor speed on the classification efficiency. The optimal parameters for grade were 400 rpm motor speed, shutter opening of 1 mm, and feed size of -0.066 mm + 0.044 mm. For the recovery, the optimal conditions were 1200 rpm motor speed, shutter opening of 2.5 mm, and feed size of -0.044 mm. The most favorable balance of grade (67.8%) and recovery (53.2%) was achieved with a motor speed of 1200 rpm, shutter opening of 4 mm, and feed size of -0.066 mm + 0.044 mm. The work concludes that air classification significantly enhances the PAL beneficiation process, with a 50% increase in grade, and recommends exploring the low shear grinding techniques for further improvement.
