Removal characteristics of fine Fe-compound particles with paramagnetism from very low concentration suspension by high gradient magnetic separator (HGMS) with fibre matrix

The characteristics of fine Fe-compound particle removal by an HGMS with fibre matrix are studied. The removal efficiency, R, of the particles by the HGMS is expressed as follows: 1-R=ln(631k*β)sup(n), β=epsilon.h/d* *.(1-epsilon)/u sub(L).u sub(M)/u sub(G) where k* is equivalent mass transfer rate and n is a constant. The particle concentration gradient, dC/dx, in the matrix is independent of C and depends on x. The equivalent mass transfer rate, k*, is dependent on the particle diameter, d. When d is less than 1 μm, k* equals 2.2x10-7cm/s and when d is greater than 1 μm, k* depends on the particle form, i.e. k* is 1.27x10-7cm/s for particles without protrusion and is 2.83x10-6cm/s for particles with protrusion. But when u sub(L)/epsilon(1-epsilon) is greater than 224cm/s, R decreases because of the through-pass phenomenon in the matrix. (author)