Britaminas - pioneering on production of soil remineralizers out of rock

Applying HRC™ technology to rock dust production

Located in Mineiros, state of Mato Grosso, the quarry controlled by the Fortaleza group owns the first Brazilian aggregates production plant totally focused on the production of remineralizers for the agro-industry based on basalt processing. In contrast to other quarries, the plant in Mineiros does not produce rock dust for remineralization as a subproduct, but rather as the main product. Soil remineralizers gained market share thanks to studies developed by farmers and universities, which confirmed their agronomic efficiency in different cultures and soils in Brazil.

Until recently, Britaminas used a hammer mill as their main production equipment. Observing the increased demand for rock dust among regional farmers, it was necessary to improve productivity, however, with the current equipment the costs were far too high, particularly due to high energy consumption.  The company believed that only the traditional machinery—such as the hammer mill—could be used for rock dust production. Tests performed in the Metso laboratory in Sorocaba confirmed the feasibility of applying HRC technology to rock dust production, showing that it was possible to obtain the grading required by the agricultural market.

With the replacement of hammer mills by the HRC™8, Britaminas was able to triple rock dust production without increasing their energy consumption. “With the energy required by the hammer mill with a 200HP-motor to produce 2 tons/hour, the HRC™8 does 60 tons/hour,” remarks Abel Fortaleza Filho, director of Britaminas.

In addition to the scrapping of the hammer mill, a complex and expensive machine to operate and maintain, the choice of the HRC™8 reinforced the professionalism of rock dust production. Today, the quarry provides stable operation, resulting in a final product with a grading of less than 1 mm and with reduced wear, as the mills of the HRC™8 are estimated to require replacement only after five thousand hours of operation.

“We are quite satisfied because the HRC™8 produces rock dust with grading in accordance with the requirements of the agricultural producers. This is important, as in this way the soil is able to absorb all the minerals in the rock dust,” observes Abel.

With the remineralization line established, the quarry can serve producers of sugar cane, soybean, corn, eucalyptus and pasture within a radius of up to 200 km, but Britaminas already received inquiries for delivery of rock dust to the city of Sinop, located north in Mato Grosso state and outside the operating area established by the company.

Natural alternative for enriching the soil

The name of the technology is derived, obviously, from the use of rocks, a natural source of minerals, to restore soil fertility. Also known as soil remineralization, the process has been developed in Brazil since the 1950s. With the regulation of its use by the Ministry of Agriculture, Livestock and Supply in March 2016, the process of remineralization assumed a new status. Today, remineralization is considered as a complementary process to the use of chemical fertilizers, as well as a natural alternative for enriching the soil.

In order to market rock dust, companies have to comply with the technical requirements of the Brazilian Ministry of Agriculture, Livestock, and Supply, performing tests to assure the agronomic efficiency of the product. Another aspect to be highlighted is the distance between the source of the rock dust and its potential end-users. According to a specialist's evaluation, rock dust production should not be further away than 300 km from the rural property in order to be economically feasible. 

“The HRC™8 is the ideal equipment to serve this new aggregates production frontier,” explains Alfredo Maia Reggio, Head of the sales department at Metso. In his opinion, the grinding rolls are compactors which produce rock dust in grading meeting the norms for soil remineralization determined by the Brazilian Ministry of Agriculture, Livestock, and Supply, with increased production.

According to Reggio, the equipment also contributes to the sustainability of remineralization, as it reduces energy consumption in comparison to the hammer mill and does not use water in the process. Other environmental benefits include the reduction of the noise caused by the production and the possibility to adopt a more sustainable culture by using natural products, such as rock dust.