Studies On Fundamentals Of Ballability Of Iron Concentrates

A lot of work has been devoted to the study of the influences of binder and raw materials characteristics on ballability of iron ore concentrates.However, the theories couldn't predict the granulation behaviour from the fundamental properties of raw materials.Therefore, it is theoretical and realistic significance for ballability perfected, properties of green balls improved and the pellets industry's development promoted by studying the effects of binder and iron concentrates on ballablity.In this paper, Using two kinds of iron ore concentrates and two kinds of binder as raw materials, the influences of moisture, particles characteristic and properties of binder on the ballability of iron concentrates were studied.The results showed that the suitable moisture of 10.0%～11.0% for hematite pellets was higher than that of magnetite among 8.0%～9.0%and the water saturation(S)of green ball was in porprotion to growth rate (V) of pellets.So the Ballability evaluation criterion by saturation of green balls was more scientifically and soundly than by contents of mositure.The result of effects of particles characteristic on granulation showed that the specific area of raw material in proportion to growth rate of pellets,and the suitable specific area higher than 1500 cm2/g. So take the specific area as the criterion of ballablity was more scientifically than average size.The influences of bentonite on properties of concentrates showed that growth rate of green ball were in inverse proportion to contents of bentonite (w).The strength of drop number and compress strength of green pellets increased as the viscosity and capillary force increased. When contents of bentonite was 2.0% both two kinds of concentrates drop number was 4.9times/0.5m and 4.1times/0.5m, respectively, the compress strength was 10.33N/p and 8.52N/p, respectively.The effects of compound binder on Ballability of two kinds of concentrates were differents.The growth rate of magnetite pellets decreased with dosage of F increasing. While the grow rate of hematite pellet increased among the dosage of F arrange from 0% to 1.0%.The effects of liquid bridge viscosity on ballability showed that the growth rate of hematite concentrate green ball higher than growth rate of magnetite concentrate under the same conditions. But the growth rate of both kinds of pellets were in proportion toη=-1/2. When the viscosity of liquid bridge reduced to lOmpa.s the drop number and compress strength of two kinks of iron concentrates were increased.