It is important to maintain a certain amount of melt during sintering of iron ores to improve product yield and strength of sinter product. Spreading phenomena of the initial melt within adhering layer in pseudo-particles are essential to achieve efficient agglomeration. Penetration tests have been conducted to demonstrate the spreading behavior of the initial melt. Paired samples consisting of ore tablet and initial melt tablet were heated and penetration length was measured. Penetration behavior of melt during sintering was discussed on a base of capillarity. Determining factors of penetration were morphology of the ore surface before and after dehydration and chemical composition of ores. Product yield and the strength of sinter were reflected by the penetration length of blended ores in a sintering plant.

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This paper provides an overview of chemical and physical properties of Marra Mamba ores as well as their influence on sintering performance. Evaluation tests focusing on basic characteristics, granulation ability and melting behavior have been conducted by using Ore W, a newly shipped bland of Marra Mamba ore. Although the amount of gangue minerals in Marra Mamba ores is smaller than that of other Australian ores, they have high combined water content and high fraction of fine particles. They have inferior granulation ability and required high moisture content in granulation due to their porous structure. Cohesive strength of fine ores is still low level even at high moisture content due to small kaolinite content. Penetration behavior of melt from fine particles is superior due to their low gangue mineral content, while assimilation behavior of coarse ores is inferior, resulting in poor agglomeration despite favorable behavior during heating-up in term of crack formation. Pot test results performed by BHP Billion showed decrease of strength and product yield with large amount of use. Improvement of strength was achieved by increasing moisture content during granulation. Intensification of granulation with pre-treatment or palletizing of Marra Mamba ores must be one of the key technologies for utilization of them.

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Nucleophilic addition of imidazolines to 1-halo-1-alkynes takes place by simple heating in DMF without any additives to give (Z)-N-(1-halo-1-alken-2-yl)imidazolines in good yield and in a highly regio- and stereoselective manner. These reaction conditions are also valid for the similar addition of imidazoles.