Effective capture radius estimated from single wire buildup process in high gradient magnetic separation

The effective capture radius is shown to be estimated from the single wire buildup study through the next equation. , where is the effective density of as-captured particles, dS/dt is the rate of increase of the particle retention cross section, Cinand voare the concentration and the velocity of the feed slurry, respectively, and a is the wire radius. Using α-Fe2O3particles, it is found that , where S is the buildup cross section, , and τ is the characteristic time depending on voand the applied field Ho. From these two equations, it is found that , where . This relation can adequately be explained by the existing theory. Another finding is or . The dependence of τ or on Hocan be explained by considering the weak ferromagnetic nature of α-Fe2O3. However, to explain the dependence of τ or on vo, the introduction of the sticking factor, namely the probability that a particle arrived at the wire surface is actually captured, seems to be required.