Capture radius of magnetic particles in random cylindrical matrices in high gradient magnetic separation

Vortex magnetic separation (VMS) is a new technique (1-3) which can not only greatly increase selectivity of high gradient magnetic separation but can also provide a much higher material throughput because high slurry velocity is used. This technique will have a wide range of applications in fields as diverse as mineral processing, biochemical engineering, sewage and wastewater treatment and industrial effluent treatment. At present in high gradient magnetic separation (HGMS) low Reynolds numbers (with respect to the wire diameter) are usually used and the magnetic product is captured on the upstream side of the wire matrix which results in a serious mechanical entrainment problem that is very detrimental to the purity of the magnetic fraction and to the reduction of the quantity of non-magnetic fraction (4). Vortex magnetic separation runs at moderate Reynolds number ( Re = 6–40) which leads to the formation of vortex flow in the neighbourhood of the matrix. Magnetic particles in the slurry are first concentrated in the boundary layer flow around the matrix and then brought into the magnetically attractive area on the matrix downstream side. The magnetic deposit on the downstream side of the matrix does not suffer the direct collisions with non-magnetic particles in the slurry, so the quality of the magnetic product is drastically improved. As will be described below, a new invention has been made with regard to the VMS matrix which allows capture to take place on both the upstream and downstream sides of the matrix without mechanical entrainment. This paper reviews experimental and theoretical work on the mechanisms involved in vortex magnetic separation.

Download Full-text

Investigation of Combination of Variable Diameter Rod Elements in Rod Matrix on High Gradient Magnetic Separation Performance

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1030-1032.1193 ◽

2014 ◽

Vol 1030-1032 ◽

pp. 1193-1196 ◽

Cited By ~ 1

Author(s):

Li Ding ◽

Lu Zheng Chen ◽

Jian Wu Zeng

Keyword(s):

Magnetic Separation ◽

Magnetic Particles ◽

Decisive Role ◽

Matrix Analysis ◽

Separation Performance ◽

High Gradient Magnetic Separation ◽

High Gradient ◽

Variable Diameter ◽

Oxidized Iron ◽

Weakly Magnetic

Rod matrix is effectively applied to separate fine weakly magnetic particles in pulsating high gradient magnetic separation (PHGMS), due to its reliable operation, simple combination and resistance to mechanical entrainment. They are now used to beneficiate oxidized iron ores, ilmenite, and wolframite, etc., and to purify wastewater. The combination of variable diameters rod elements in rod matrix plays a decisive role in recovery most of the different size fractions of magnetic particles, thus generating a significant influence on the performance of PHGMS. Combination of variable diameter rod elements in rod matrix on PHGMS is investigated in combination of 3 mm and 2 mm rod elements in rod matrix, by Slice-Matrix Analysis (SMA); it was found that the recovery of combinatorial rod matrix is higher than single diameter of matrix on PHGMS.

Download Full-text

Effect of Feed Solids on High Gradient Magnetic Separation of Cylindrical Magnetic Matrix

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.881-883.1634 ◽

2014 ◽

Vol 881-883 ◽

pp. 1634-1637

Author(s):

Ding Li ◽

Lu Zheng Chen ◽

Jian Xiong Huang ◽

Jian Wu Zeng

Keyword(s):

Magnetic Separation ◽

Magnetic Particles ◽

Decisive Role ◽

Matrix Analysis ◽

High Gradient Magnetic Separation ◽

High Gradient ◽

Matrix Layer ◽

The Matrix ◽

Single Matrix ◽

The Magnetic Field

Cylindrical magnetic medium (rod matrix) serves as the carrier for magnetic particles in pulsating high gradient magnetic separation (PHGMS), which has been widely applied to beneficiate hematite, ilmenite, limonite, siderite, wolframite, etc., in the mineral processing industry and to purify wastewater. The arrangement of rod elements in the matrix plays a decisive role in the magnetic field distribution and in the movement of particles in the matrix, thus generating a significant influence on the performance of PHGMS. The effect of feed solids on PHGMS is investigated in the 3 mm rod matrix of different spacings between rods in a single matrix layer, by Slice-Matrix Analysis; it was found that there is a maximum feed solids for a given matrix; beyond this feed solids, the performance of PHGMS deteriorates significantly.

Download Full-text