Vale has produced about 250,000 tons of sustainable sand products, which are certified to replace sand that is often illegally mined.

After 7 years of research and investment of about 50 million reais, Vale has developed a production process for high-quality sand products, which can be used in the construction industry. The company has applied this sand product production process to the iron ore operation area in Minas Gerais, and transforms the sandy materials that originally required the use of dams or stacking methods into products. The production process Subject to the same quality control as iron ore production. This year, the company has processed and produced about 250,000 tons of sustainable sand products, and the company plans to sell or donate them for the production of concrete, mortar and cement or for pavement paving.

Mr. Marcello Spinelli, Executive Vice President of Vale’s Iron Ore Business, said that sand products are the result of more sustainable operation practices. He said: “This project has prompted us to form a circular economy internally. There is a huge demand for sand in the construction industry. Our sand products provide a reliable alternative to the construction industry, while reducing the environmental and social impacts of tailings disposal. Influence.”

Bulkoutu mining area sustainable sand product storage yard

According to United Nations estimates, the global annual demand for sand is about 40 to 50 billion tons. Sand has become the most exploited natural resource after water, and this resource is being exploited illegally and predatory on a global scale.

Vale’s sustainable sand products are considered a by-product of iron ore. The raw ore in the form of rock mined from nature becomes iron ore after several physical processing procedures such as crushing, screening, grinding and beneficiation in the factory. Vale’s innovation lies in the reprocessing of iron ore by-products in the beneficiation stage until it reaches the necessary quality requirements and becomes a commercial product. In the traditional beneficiation process, these materials will become tailings, which are disposed of through the use of dams or in stacks. Now, every ton of sand product produced means a reduction of one ton of tailings.

The sand products produced from the iron ore processing process are 100% certified. They have high silicon content and extremely low iron content, and have high chemical uniformity and particle size uniformity. Mr. Jefferson Corraide, executive manager of the Brucutu and Agualimpa integrated operations area, said that this kind of sand product is not dangerous. “Our sand products are basically processed by physical methods, and the chemical composition of the materials is not changed during the processing, so the products are non-toxic and harmless.”

The application of Vale’s sand products in concrete and mortar has recently been certified by the Brazilian Institute of Scientific Research (IPT), Falcão Bauer and ConsultareLabCon, three professional laboratories.

Researchers from the Institute of Sustainable Minerals at the University of Queensland in Australia and the University of Geneva in Switzerland are conducting an independent study to analyze the characteristics of Vale sand products to understand whether this alternative building material derived from ore can become a sustainable source of sand And significantly reduce the amount of waste generated by mining activities. Researchers use the term “oresand” to refer to sand products that are derived from ore by-products and produced through processing.

production scale

Vale is committed to selling or donating more than 1 million tons of sand products by 2022. Its buyers come from four regions including Minas Gerais, Espirito Santo, Sao Paulo and Brasilia. The company predicts that by 2023, the output of sand products will reach 2 million tons.

“We are ready to further expand the application market of sand products from 2023. For this purpose, we have set up a dedicated team to invest in this new business. They will apply the sand product production process to the existing production process to meet market demand.” Mr. Rogério Nogueira, Director of Vale Iron Ore Marketing, said.

Vale is currently producing sand products at the Brucutu mine in San Gonzalo de Abaisau, Minas Gerais, which will be sold or donated.

Other mining areas in Minas Gerais are also making environmental and mining adjustments to incorporate sand production processes. “These mining areas produce sandy materials with high silicon content, which can be used in different industries. We are cooperating with many institutions including universities, research centers and domestic and foreign companies to develop new solutions to provide new iron ore tailings. Way out.” Mr. André Vilhena, Vale’s new business manager emphasized.

In addition to using the existing infrastructure in the iron ore mining area, Vale has also developed a transportation network consisting of railways and roads to transport sand products to multiple states in Brazil. “Our focus is to ensure the sustainability of the iron ore business. Through this new business, we hope to minimize the environmental impact, while seeking opportunities to promote employment and increase income.” Mr. Verena added.

ecological products

Vale has been conducting research on tailings application since 2014. Last year, the company opened the Puku Brick Factory, which is the first pilot factory to produce construction products using tailings from mining activities as the main raw material. The plant is located in the Pico mining area in Itabilito, Minas Gerais, and aims to promote a circular economy in the processing of iron ore.

The Federal Center for Science and Technology Education of Minas Gerais and the Pico Brick Factory launched technical cooperation and sent 10 researchers including professors, laboratory technicians, graduate, undergraduate and technical course students to the factory. During the cooperation period, we will work at the factory site, and the products during the research and development period will not be sold to the outside world.

Vale is also cooperating with the Itabira campus of Federal University of Itajuba to study the method of using sand products for paving. The company plans to donate sand products to the local area for paving.

More sustainable mining

In addition to developing ecological products, Vale has also taken other measures to reduce tailings and make mining activities more sustainable. The company has been committed to developing dry processing technology that does not require water. At present, about 70% of Vale’s iron ore products are produced through dry processing, and this proportion will remain unchanged even after the annual production capacity is increased to 400 million tons and new projects are put into operation. In 2015, iron ore produced by dry processing only accounted for 40% of the total output.

Whether dry processing can be used is related to the quality of the iron ore mined. The iron ore in Carajás has a high iron content (over 65%), and the processing process only needs to be crushed and screened according to particle size.

The average iron content of some mining areas in Minas Gerais is 40%. The traditional treatment method is to increase the iron content of the ore by adding water to beneficiation. Most of the resulting tailings are stacked in tailings dams or pits. Vale has used another technology for the beneficiation of low-grade iron ore, namely the dry magnetic separation of fine ore (FDMS) technology. The magnetic separation process of iron ore does not require water, so there is no need to use tailings dams.

The dry magnetic separation technology for fine ore was developed in Brazil by NewSteel, which was acquired by Vale in 2018, and has been applied in a pilot plant in Minas Gerais. The first commercial plant will be put into use in the Vargem Grande operating area in 2023. The plant will have an annual production capacity of 1.5 million tons and a total investment of US$150 million.

Another technology that can reduce the demand for tailings dams is to filter the tailings and store them in dry stacks. After the annual iron ore production capacity reaches 400 million tons, most of the 60 million tons (accounting for 15% of the total production capacity) will use this technology to filter and store tailings. Vale has opened a tailings filtration plant in the Great Varzhin mining area, and plans to open three more tailings filtration plants in the first quarter of 2022, one of which is located in the Brucutu mining area and the other two are located in Itabira Mining area. After that, the iron ore produced by the traditional wet beneficiation process will only account for 15% of the total production capacity, and the tailings produced will be stored in tailings dams or deactivated mine pits.