Tag Archives: Rogério Nogueira

Vale makes headway on low-emission iron ore briquette development

Vale says it has successfully tested a new type of iron ore briquette, adapted for the direct reduction route, which will contribute to the decarbonisation of steel production.

The new type of briquette, which will support the steel industry’s efforts to meet emission reduction targets worldwide, emits about 80% less CO2 compared with pellets in its manufacture, abating the company’s direct and indirect emissions (Scope 1 and 2). The briquette can also be used as a charge for the blast furnace (BF-BOF).

Direct reduction is one of the routes used in steel production. It is considered cleaner than the blast furnace route as it uses natural gas instead of coke – an input obtained from coking coal – and, therefore, emits less carbon and other greenhouse gases (GHG).

The production of briquette meets the trend of the steel industry to increasingly adopt the direct reduction route, Vale says. Studies show that for every tonne of steel produced in the blast furnace, two tonnes of CO2 are emitted, while in direct reduction, carbon emissions fall to 0.6-1 t.

In recent months, Vale has stepped up development of a new type of briquette for this route. So far, seven experimental tests have been carried out at plants for different clients in the Americas. The tests, known as basket tests, have involved small quantities of briquette and pellets being placed side by side in baskets, which fed the reactors.

Rogério Nogueira, Vale’s Director of Product and Business Development, said: “With the development of this new type of briquette, Vale is taking another important step in its contribution to reducing emissions from the steelmaking chain through innovation, always in close collaboration with its clients and development partners.”

In one of the tests carried out, for example, the new product outperformed pellets in metallisation, reaching a metallic iron content of around 98%, while pellets reached 95%. This result indicates that the new type of briquette can improve the productivity of steel mill clients, Vale says.

The briquette also performed well in terms of disintegration. In one of the tests, for example, around 7% of fines were generated, against 14% with the use of pellets. The smaller presence of fine particles as a result of the disintegration facilitates the passage of the gas through the reactor, increasing productivity and reducing the consumption of this fuel, which contributes to reduced carbon emissions.

The next step in the development of the direct reduction briquette is to carry out industrial tests, which should begin in June, in a reactor of a client in North America.

Announced by Vale in 2021 after about 20 years of development, the briquette is produced from the agglomeration of iron ore at low temperatures using a technological solution of binders, which gives the final product high mechanical strength. Therefore, it emits less pollutants and GHG when compared with traditional agglomeration processes (pelletisation and sintering).

The briquette can substitute any direct load (sinter, granulates and pellets) in the steel mill furnaces, according to Vale. The substitution of the sintering stage in the blast furnace route is what allows the potential reduction of GHG emissions by up to 10%. This route is the most used worldwide, while direct reduction is more common in regions with abundant natural gas at competitive prices, such as the Middle East, North America and Argentina.

To be produced, direct reduction agglomerates (briquettes and pellets) require iron ore with a higher content, approximately 67% Fe, alongside low rates of contaminants such as silica and alumina. Agglomerates for blast furnaces can be produced with ore grades lower than 65% Fe.

Vale says it is working to increase its production of high-quality iron ore and expand its capacity to concentrate ore, which also raises the iron ore grade, enabling the company to meet demand from steelmakers for these products.

The company is building two 6 Mt/y briquette plants at its Tubarão Unit in Vitória, Espírito Santo, Brazil. Start-up of the first plant is planned for the end of the first half of the year, while the second should begin operations at the end of the year.

In addition, memorandums of understanding have already been signed with more than 30 customers to study the implementation of decarbonisation solutions, including the construction of briquette plants located on the premises of some customers.

Among the agreements signed, three aim to install Mega Hubs in Middle Eastern countries (Saudi Arabia, United Arab Emirates and Oman) to produce hot-briquetted iron (HBI) to supply both local and seaborne markets, with a significant reduction in CO2 emissions. At the hubs, Vale is expected to build and operate iron ore concentration and briquetting plants, supplying the feed for the HBI plants, which will be built and operated by investors and/or customers. Vale is also studying the creation of similar hubs in Brazil.

Iron ore briquette contributes to achieving Vale’s commitment of reducing its Scope 3 net emissions by 15% by 2035. The company also seeks to reduce its absolute Scope 1 and 2 emissions by 33% by 2030 and achieve neutrality by 2050, in line with the Paris Agreement ambition to limit global warming below 2°C by the end of the century.

Vale adapts iron ore processing route to make sand product for construction sector

After seven years of research and investment of about BRL50 million ($8.9 million), Vale says it has developed a process for producing sand from its production processes with applications in the construction market.

After adaptation in the state of Minas Gerais’ iron ore operations, the sandy material, previously disposed in piles and dams, is now being processed and transformed into a product, following the same quality controls used in the production of iron ore. This year, around 250,000 t of sand has been processed and destined for sale or donation to be used in concrete, mortar, cement and road pavement.

According to Marcello Spinelli, Vale’s Executive Vice President for Iron Ore, the development of this product is the result of more sustainable operating practices.

“This action promotes a circular economy within our units and reduces the impact of tailings disposal for the environment and the society, in addition to being a reliable alternative for the construction industry, where the demand for sand is high,” he said.

Sustainable sand stock yard at Brucutu

Vale’s Sustainable Sand is considered a co-product of the iron ore production process. The material extracted in the form of rocks undergoes several physical processes in the plant, such as crushing, classification, grinding and concentration, until iron ore is obtained.

The innovation introduced by Vale lies in the concentration stage where the by-product of the iron ore processing is once more processed until it reaches the necessary quality to become sand for commercial use. In the traditional method, this material would become tailings and be destined to dams or piles. Every tonne of sand produced represents one less tonne of tailings being generated.

The sand resulting from the iron ore treatment is a 100% certified product, with high silica content and very low iron content, in addition to high chemical and granulometric uniformity.

According to Jefferson Corraide, Executive Manager of the Brucutu and Água Limpa Complex, the sand does not have hazardous characteristics in its composition.

“The mineral processing to obtain the sand is essentially physical, not altering the composition of the materials, so the product is not toxic,” Corraide said.

Recently, Vale’s sand had its application in concrete and mortar certified by three specialised laboratories in Brazil: Instituto de Pesquisas Tecnológicas, Falcão Bauer and ConsultareLabCon.

The properties of Vale sand are also being analysed by an independent study conducted by researchers from the University of Queensland’s Sustainable Minerals Institute (Australia) and the University of Geneva (Switzerland), who are investigating whether alternative construction materials produced from mineral ores could become a sustainable source of sand while significantly reducing the volume of waste produced by mining. These researchers introduced the term “ore sand” to refer to this type of processed sand sourced as a co-product or by-product of mineral ores.

Precast concrete produced with Vale’s Sustainable Sand

Production scale

Vale has already committed to allocating more than 1 Mt of sand for sale or donation in 2022. Buyers are companies operating in four different regions in Brazil: Minas Gerais, Espírito Santo, São Paulo and Brasília. It is estimated that, in 2023, production will reach 2 Mt.

Rogério Nogueira, Director of Ferrous Marketing, explained: “We are getting ready to scale up the sand destination even more from 2023. For this purpose, we have a team of professionals dedicated to this new business and adapting our operations to meet the market needs.”

Currently, Vale is producing sand for sale and donation at the Brucutu Mine, in São Gonçalo do Rio Abaixo (Minas Gerais).

Other mines of the company, also located in Minas Gerais, are in the process of obtaining environmental and mining approvals for sand production.

André Vilhena, Manager of New Businesses at Vale, said: “Our mines provide a sandy material that is rich in silica, which can be used in different industries. We are working with several institutions, including universities, research centres and Brazilian and foreign companies, to develop new solutions to give new destinations to iron ore tailings.”

In addition to using the existing infrastructure in the iron ore mines, Vale also has a railway and road network to transport the sand to markets in several Brazilian states. “With this activity, our main focus is on the sustainability of our iron ore operations, minimising the environmental liabilities, in addition to seeking to promote employment and income by means of new businesses,” Vilhena said.

Eco products

Vale has been carrying out tailings application studies since 2014. Last year, the company inaugurated the Pico Block Factory, the first pilot plant for construction products whose main raw material is tailings from mining activity. Installed at the Pico Mine, in the municipality of Itabirito (Minas Gerais), the factory promotes a circular economy in iron ore processing operation.

The Federal Center for Technological Education of Minas Gerais (CEFET-MG) provides technical cooperation with the Block Factory. Ten researchers from the institution are working on site during this period, including professors, laboratory technicians and graduates, undergraduates and technical course students. During the R&D period, the products will not be sold.

Another research initiative aims to develop the use of sand in pavement solutions in partnership with Itabira’s campus of the Federal University of Itajubá (Unifei). The focus is on the donation of sand for the pavement of local roads.

More sustainable mining

In addition to the Eco products line, Vale has other initiatives to make its mining more sustainable and reduce the generation of tailings. The company has been developing technology to increase the dry processing of its ores, which does not require the use of water. Currently, around 70% of Vale’s production is dry processed and this shall remain at this level when the production capacity of 400 Mt/y is reached and after the start-up of new projects. In 2015, this figure was 40%.

In Carajás, as the iron content is already high (above 65% Fe), the material is only crushed and screened to be classified by size (granulometry).

In Minas Gerais, in some mines, the average content is 40% Fe. By the conventional method, the ore is concentrated by means of processing with water to increase the iron content, with most of the tailings deposited in dams or pits. This is where another technology under implementation at Vale stands out: FDMS (Fines Dry Magnetic Separation). This technology sees the magnetic concentration of ores of low iron grade with no use of water, and therefore, with no need for dams.

Developed in Brazil by New Steel, a company acquired by Vale in 2018, this technology is already in use in a pilot plant in Minas Gerais. In 2023, the first commercial plant will start up in Vargem Grande, with a production capacity of 1.5 Mt/y and investment of up to $150 million.

Another technology which reduces the need of dams is tailings filtration and subsequent dry piling. Once the capacity of 400 Mt/y is reached, more than 60 Mt/y (or 15% of this total) will be processed in plants, where most of the tailings will be filtered and piled this way.

Vale has already opened a filtration plant in Vargem Grande and three more will be commissioned in the March quarter of 2022: one in Brucutu and two in Itabira. Only 15% of the production will continue to be processed by the conventional method, with wet concentration and disposal in dams or deactivated mine pits.