BR-102024018226-A2 - AUTOMATIC DEVICE FOR PERFORMING RESISTANCE TESTS ON AGGLOMERATES AND GRANULATES OF ORES AND TAILINGS

BR102024018226A2BR 102024018226 A2BR102024018226 A2BR 102024018226A2BR-102024018226-A2

Abstract

The present invention consists of an automatic device for performing Shatter tests on agglomerates and granules of ores and tailings characterized by: a lower box consisting of gates that open automatically and an automatic sieve (1), an upper box consisting of gates that open automatically and an automatic sieve (2), a scale (3), a motor that makes a 180° turn (4) and an automation system (5).

Inventors

FABRICIO VILELA PARREIRA
LUIZ PAULO BERTOLDO
FLÁVIO DE CASTRO DUTRA
VALDIRENE GONZAGA DE RESENDE
FELIPE VIANA PIMENTA
FRANCISCO JUNIOR BATISTA PEDROSA
ERIC AUGUSTIN
TAYNÁ CUNHA SOUZA
SANDRA LÚCIA DE MORAES
ANDRÉ LUIZ NUNIS DA SILVA

Assignees

VALE S.A.

Dates

Publication Date: 20260317
Application Date: 20240904

Claims (1)

1. Automatic device for performing Shatter tests on agglomerates and granules of ores and tailings characterized by: a lower box consisting of gates that open automatically and an automatic sieve (1), an upper box consisting of gates that open automatically and an automatic sieve (2), a scale (3), a motor that makes a 180° turn (4) and an automation system (5).

Description

Field of invention [0001] The present invention is within the field of mineral-metallurgical technologies and comprises the development of equipment for carrying out Shatter tests, which measures the mechanical impact resistance of agglomerates, such as pellets, briquettes and sinters, granules and residues. [0002] More specifically, the present invention is in the field of devices for automating standardized tests that evaluate the resistance to compression, abrasion (tumbling) and impact (shatter) of agglomerates and granules of ores and waste. State of the art [0003] Iron ore agglomerates are fundamental in the exploitation of low-grade iron ore deposits and in the decarbonization of the steel industry, as they are "engineered" products in terms of chemical composition, shape, and mechanical strength. Although chemical composition is the key factor in the performance of reduction reactors, mechanical strength is a prerequisite, especially when dealing with agglomerates destined for the transoceanic market. As transport, handling, and stacking or bed disposal operations involve different stresses, it is of fundamental importance to carry out characterization tests that simulate these stresses as closely as possible. [0004] Conventionally, iron ore agglomerates are characterized by standardized tests that evaluate resistance to compression, abrasion (tumbling), and impact (shatter). The traditional shatter test is performed on sinters, according to a procedure that evaluates the degradation of the product after 4 successive drops. However, in general, performing 4 drops on agglomerates with high mechanical resistance (pellets and briquettes) is not sufficient to discretize the performance of products produced from different mixtures and/or production methods. Therefore, an alternative method, called Stressed Shatter, was developed, which consists of recording the number of drops that the agglomerate withstands to reach a shatter index of 85%. This test, which has been conducted manually, can now be conducted on an Automatic Shatter. The results of the Stressed Shatter tests conducted on the manual and automatic equipment are relatively similar, with a difference of 3%. The results presented in this study qualify the Automatic Shatter method as a way to characterize agglomerates, with the advantage of reducing labor and minimizing the risk of accidents. This equipment and method could be used in R&D centers, as well as for quality control of processes and products in the mining and steel industries. [0005] Throughout the development of the iron and steel production chain, the utilization of iron ore has always been linked to subsequent steelmaking processes. Initially, only granulated "lump" iron ore (-30 + 6.3 mm) was suitable for reduction processes, given the operational limitations of conventional reactors (blast furnaces and direct reduction reactors) in processing fines. Because of this, the fines were then discarded as tailings. [0006] To overcome the aforementioned limitation, the sintering process was initially developed, which agglomerates particles with a granulometry between 6.3 and 0.15 mm, resulting in sinter. This agglomerate is irregular and has high porosity, which results in insufficient mechanical resistance to withstand the stresses imposed by transport and handling over long distances. This particularity implies the need for sintering plants to be integrated with blast furnaces (Meyer, K., 1980). [0007] In the mid-20th century, a new agglomeration process, called pelletizing, was developed, which agglomerates particles smaller than 0.15 mm. Initially, this process was used to utilize fines that were not used in sintering. Subsequently, with the development of flotation and magnetic separation processes, pelletizing also began to be used in the agglomeration of iron ore concentrates (Meyer, K., 1980). The combination of these technologies was considered a milestone, as it allowed the utilization of low-grade iron ores with fine liberation particle sizes, in addition to enabling the production of premium pellets with high iron content and low contaminant levels. These characteristics are indispensable in the direct reduction process, which has gained increasing prominence given decarbonization initiatives. [0008] In addition to the aforementioned agglomeration processes, another technology that has recently gained prominence in iron ore agglomeration is briquetting. According to Meyer (Meyer, K., 1980), briquetting is the simplest and oldest agglomeration process, in which fine particles are pressed together to form briquette agglomerates that can take on different shapes, depending on the design of the roller pockets. In this process, the mixture used can consist of water and binders depending on the characteristics of the material to be agglomerated. The briquettes produced can undergo heat treatment or, depending on their physical characteristics, can proceed directly to the subsequent