The New Zealand sea sand ore is a kind of vanadia–titania magnetite formed by erosion in the coastal zone. Because of its coarse particle size, smooth spherical particles, complex chemical composition, it has been added to sinter as an auxiliary material. Based on the principle of optimizing ore blending to strengthen advantages and weaken disadvantages, this paper used New Zealand sea sand raw ore that has not undergone any pretreatment as the main material and prepared it into oxidized pellets using a disc pelletizer and explored the influence of high-proportion unground sea sand ore on the preparation process and reduction performance of oxidized pellets. The influence of unground sea sand ore on the falling strength, compressive strength, reduction swelling index, and reduction degree of pellets was analyzed by the ICPAES, XRF, XRD, SEM-EDS, and other detection methods, and the change laws and influencing factors of oxidized pellets were analyzed. With the increase of the amount of unground sea sand ore used, the falling strength and compressive strength of the green pellets first decreased and then gradually increased, while the compressive strength of the oxidized pellets first increased and then decreased. At the same time, as the amount of sea sand ore used increased, the reduction process of pellets was restricted. The reduction swelling index and the reduction degree index generally show a downward trend. However, the compressive strength of the pellets gradually increased after reduction. Through the research on the pellet-forming performance and reduction properties of unground sea sand ore, it is shown that when the amount of unground sea sand ore used was 40%, it can still be used as raw material for blast furnace ironmaking. Thus, this research provided specific data support for iron and steel enterprises to improve the ratio of unground sea sand ore and reduce production cost.

中文翻译：

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高比例未研磨海砂矿石对氧化球团矿制备工艺及还原性能的影响

新西兰海砂矿石是一种钒铁-二氧化钛磁铁矿，是由沿海地区的侵蚀形成的。由于其粒径大，光滑的球形颗粒，复杂的化学成分，已将其作为辅助材料添加到烧结矿中。基于优化矿石混合以增强优势和减弱劣势的原理，本文以未经预处理的新西兰海砂原矿为主要原料，并使用圆盘造粒机将其制成氧化球团，并探讨了比例未磨碎的海砂矿石对氧化球团矿的制备工艺及还原性能的影响。ICPAES，XRF，XRD，SEM-EDS分析了未磨碎的海砂矿石对下落强度，抗压强度，还原溶胀指数和球团还原程度的影响，分析了其他检测方法，分析了氧化球团的变化规律和影响因素。随着未研磨海砂矿石使用量的增加，生丸的下降强度和抗压强度先降低然后逐渐增加，而氧化丸的抗压强度先增加然后降低。同时，随着海砂矿石用量的增加，颗粒的还原过程受到限制。还原溶胀指数和还原度指数总体上呈下降趋势。但是，还原后粒料的抗压强度逐渐增加。通过对未研磨海砂矿石的造粒性能和还原性能的研究，发现当未研磨海砂矿石的用量为40％时，它仍然可以用作高炉炼铁的原料。因此，本研究为钢铁企业提高未研磨海砂矿石比例，降低生产成本提供了具体的数据支持。