Red Mud Minimization by Iron Removal

通过除铁最大限度地减少赤泥

• 批准号: 9714594
• 负责人: Mark Schlesinger
• 金额: $ 25.97万
• 依托单位: Missouri University of Science and Technology
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-09-01 至 2002-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9714594&HistoricalAwards=false
• 关键词: Red; Mud; Minimization; Iron; Removal

9714594 Schlesinger The objective of this research is to demonstrate the use of partial reduction as a means of removing the iron from "red mud", produced in the purification of aluminum using the Bayer process. Red mud contains high ferric-oxide, resulting in its name, as well as significant percentages of alumina, soda, silica, lime and titania, and might prove a valuable source of these materials. Currently red mud is disposed of at sea or in shallow lagoons along ocean shores or river banks. Because of the less-hazardous nature of red mud, little research attention has been given to reducing the volume of disposed material or the recovery of its constituents. Several characteristics of red mud make the development of an economically viable treatment process difficult, e.g. the moisture content, the extremely fine particle size and the refractory nature of most of its constituents. One of the most challenging aspects lies in finding a way of separating the iron it contains (in the form of hematite). Several techniques have been attempted, but they have been unsuccessful because of their high energy requirements and because they produce a slag which is difficult to process further. This research is aimed at reducing the hematite to magetite or wustite, which are ferromagnetic and can be recovered by low-gradient magnetic separation processes. This would require lower furnace temperatures, reducing energy costs and minimizing interaction among the other constituents in the mud. The research program will focus on bench-scale reduction experiments varying the type of mud, reduction temperature and the choice and amount of reducing agent; quantitative process mineralogy techniques will be used to assess the degree of reduction achieved and to generate a characterization profile of U.S. red muds. A second focus involves demonstrating the use of low-gradient magnetic separation in recovering iron from the partially reduced materials. Recent advances in magnetic separation have shown promise in iron recovery from other fine-grained process wastes and their integration into a red mud treatment process will help create a viable alternative to present disposal and recovery techniques. ***

9714594 Schlesinger这项研究的目的是证明使用部分还原作为从“红泥”中去除铁的一种手段，该手段是在使用拜耳工艺纯化铝中产生的。 红色泥浆含有高铁氧化物，其名称以及氧化铝，苏打水，二氧化硅，石灰和钛含量很大，可能是这些材料的宝贵来源。 目前，在海岸或河岸沿海或沿海沿海的浅泻湖处置了红泥。 由于红泥的性质不那么危险，因此很少有研究注意减少处置材料的数量或其成分的恢复。红泥的几个特征使经济上可行的治疗过程的发展变得困难，例如水分含量，极高的粒径和大多数成分的难治性。 最具挑战性的方面之一在于找到一种分离其所含铁的方法（以赤铁矿的形式）。 已经尝试了几种技术，但是由于它们的高能量需求，它们没有成功，并且因为它们产生了很难进一步处理的炉渣。 这项研究旨在将赤铁矿减少到马替石或钢铁石，这是铁磁磁性的，可以通过低梯度磁分离过程来回收。 这将需要较低的熔炉温度，降低能源成本，并最大程度地减少泥浆中其他成分之间的相互作用。 该研究计划将着重于台式减少实验，以改变泥浆的类型，降低温度以及还原剂的选择和数量；定量过程矿物学技术将用于评估所达到的减少程度，并产生美国红泥的特征。 第二个焦点涉及证明使用低梯度磁分离从部分还原的材料中恢复铁中的使用。 磁分离的最新进展表明，在铁从其他细粒工艺废物中恢复铁的前景，并且将它们整合到红泥处理过程中将有助于创建可行的替代方案，以实现当前处置和恢复技术。 ***