Comparing Dry and Wet High-Intensity Magnetic Separation for Iron Removal from Low-Grade Magnesite Ore

This paper investigates the removal of iron impurities from a low-grade Saudi magnesite ore (37.68% MgO and 1.91% Fe2O3). Both wet and dry high-intensity magnetic separation techniques were explored. In dry magnetic separation using an Outotec-induced roll magnetic, the feed size, feed rate, magnetic field, and roll speed were optimized. On the other hand, using a WHIMS laboratory wet high magnetic separator, the studied parameters were slurry flow rate, magnetic field, and pulp density. The results show that a maximum iron removal of 72.32% can be achieved using DHIMS (product with 0.71% Fe2O3 at (-0.212+0.05 mm) feed size, 0.3 kg/min feed rate, 14 KGauss, and a roll speed of 50 rpm. However, the optimal conditions for wet magnetic separation were magnetic field of 14 KGauss, 15 wt.% solid feed, and flow rate of 0.4 L/min, lead to a product that has 0.46% Fe2O3 which mean an iron removal of 84.25%. The product can be used in refractory materials, brake lining, leather treatment, and welding. It is also suitable for chemical, fertilizer, and wastewater treatment, flue gas treatment, and pesticides.