2008 Volume 94 Issue 11 Pages 475-482
Anionic polymer dispersant (APD) has been applied to the granulation process for enhancing sintering productivity. It is reported that APD accelerates micro-particle dispersion. In this study, the amount of micro-particles whose diameter was less than 10 μm has been surveyed by means of Andreasen pipette method. And in order to understand granulation mechanism focused on micro-particle, effect of micro-particles on granulation has been analyzed by granulation test with single ore. As results, total amount of micro-particle was in the range from 2 to 10% in all ores. The increase in amount of micro-particles by APD differed according to ores. These differences mostly could be explained with mineral characteristics of micro-particle. From the granulation test, the optimum moisture in wet state did not correspond with one in dry state. In wet state, micro-particles dispersed by APD increased effective volume of water, resulting in lowing water requirement for optimum granulation. Therefore, APD addition is seemed to enable optimum moisture of granulation to move wet optimum moisture closer to dry optimum moisture. In dry state, dispersing micro-particles may result in concentrating in contact point of iron ores and reinforces the strength of granules. This understanding based on this result can make comprehensive interpretation for granulation.
