TIG – Stockyard. Photo: Ricardo Teles.

In order to minimize the impacts caused by the production of iron ore by moisture, researchers of the Vale Institute of Technology – Mining (ITV) conducted industrial-scale tests of a technology that promises to reduce the volume of water in the product and, consequently, its production costs. By injecting hot and dry air into the transfer chute – closed equipment where the direction of the conveyor belts is changed – the project manages to achieve a moderate reduction of moisture in the sinter feed ore by up until 1.8%.

After studying economically viable ways of reducing the moisture from the ore for more than 10 years, the team successfully completed the first part of tests in the industrial scale between March 27th and April 16th at the port of Sepetiba Bay Port Company, in Rio de Janeiro. “While it [the reduction process] is performing the change of direction by means of the transfer chute, the hot and dry air will be injected onto the iron ore, in a countercurrent way”, explained Thiago Souza, a researcher at ITV Mining.

The presence of water in the ore occurs in two ways: by the physical composition of the product or by the wet processing of the iron. In addition to the costs to minimize the effects of moisture, freight and discounted prices compared to the dry base at the destination port, the volume of water in the iron may represent other expenses for our company.

“If the moisture exceeds the limit established by the international legislation of the Transportable Moisture Limit (TML), there are risks to the stability of the vessel, which, in extreme cases, may even keel over. During the loading of the vessel, when the TML limit is exceeded, the captain is in charge and may suspend the operation”, Thiago explains.

In order to consolidate the excellent results obtained in the first tests, the researchers will perform other validation processes. With the innovation, registered in patent applications in industrial property government agencies of eight countries, including Brazil, Vale brings together more competitiveness to its product, in addition to greater value and safety.