Aeration induced moisture reduction of iron ore

Mining is increasingly occurring near or below the water table. This has led to a higher rate of handling problems associated with increased moisture and increased adhesion which lead to higher rate of blockage events within the materials handling chain. Typically, these ores and minerals are known as 'wet and sticky materials'. Currently there is very limited knowledge and/or methodologies for effective design of efficient materials handling systems when it comes to handling these wet and sticky materials. However, there is one major parameter which significantly affects handleability of a wet and sticky ore, namely its moisture content. Flow property testing has shown that when moisture is reduced, the adhesive properties of the ore are also significantly reduced, thereby increasing ore flowability. The research embodied in this paper investigated the moisture reduction rate through a loose packed bed of iron ore using dry, ambient temperature airflow. A comparison of the predictive capabilities of a proposed drying model to data obtained from onsite experiments using iron ore fines is made. Building on an assumption made by Hukill (1954), a second term has been proposed to account for rewetting effects in the drying process. From this research, identification of improved moisture reduction approaches is envisaged.