Best monitoring practices help extract lithium from Brazil

By Luis Arís*

As in other countries, the demand for lithium is also encouraging the opening of new lithium mines in Brazil. A number of recent moves prove the tendency to reposition the country among the main producers of the so-called white oil. And there’s plenty of potential for exploration. According to the Geological Survey of Brazil (CPRM), the country has just made a leap in terms of contained lithium oxide (Li20) reserves, from 0.4 per cent of the world total to 8 per cent. The increase is due to CPRM’s prospecting work, especially the pilot project in the Jequitinhonha Valley.

The CPRM study pointed out potential areas for the discovery of new lithium deposits in the north-east of the state of Minas Gerais. In all, the work mapped 45 occurrences, 20 of which were unpublished and were studied and classified by the institution’s researchers. To put it another way: Brazil’s share of world production could change from the current 0.6 per cent (data from the United States Geological Survey – USGS) and turn the country into a new frontier for the production of lithium, including bold ventures.

Brazil has a lot to gain from the exploitation of lithium, an essential component of renewable energy sources such as solar panels, wind turbines and electric cars. As well as the Jequitinhonha Valley in Minas Gerais, the ore is also found in the Borborema province, located between the states of Pernambuco, Rio Grande do Norte and Ceará, and in the Solonópole province, also in Ceará. The resources and reserves of these locations amount to more than 1 million tonnes, placing Brazil as the 7th largest reserve in the world.

According to the US Geological survey, Brazil is the fifth largest lithium producer in the world, reaching 4,900 tonnes by 2023. In 2022 the amount of ore removed from Brazilian soil was just 2,630 tonnes – this growth confirms the investments in new mines and the expansion of existing mines.

One reason for this could be the fact that the price of lithium on the global market has risen from around USD 12,000 per tonne in 2019 to USD 46,000 per tonne in 2023.

Lithium-ion batteries are the cornerstone of lithium use, accounting for approximately 90 per cent of global lithium consumption by 2022. These batteries power a wide range of products:

• Consumer electronics: Smartphones, laptops, portable chargers and tablets are everywhere in today’s digital age; they are all powered by lithium-ion batteries.

• Electric vehicles (EVs): The automotive industry’s transition to electric mobility significantly increases the demand for lithium, as EVs rely on lithium-ion batteries for energy storage.

• Energy storage systems: Lithium batteries are crucial for storing solar and wind energy, facilitating the transition to renewable energy sources.

• Portable power tools: From drills to electric lawnmowers, lithium batteries offer the high energy density needed for cordless tools.

Before it can be applied in the above industries, lithium has to be extracted from the ground. Lithium extraction is typically done through a process called brine mining, which involves extracting lithium from underground saltwater reserves. This process involves pumping salt water to the surface, where it is evaporated to remove the lithium and other minerals. Unfortunately, these toxic metals can contaminate water sources, threatening not only humans but also animal biodiversity.

Each tonne of lithium mined results in 15 tonnes of CO2 emissions into the environment. In addition, it is estimated that approximately 500,000 litres of water are needed to mine approximately 2.2 million litres per tonne of lithium.

Contamination-free soil and air

Stanford University in the USA has compiled guidelines that, if implemented in lithium mining operations, could reduce the damage this industry does to nature and, at the same time, preserve critical investments for Brazil’s economic growth.

1. Lithium extraction typically requires digging open pits and treating with acids to extract the ore into an aqueous medium. A considerable amount of tailings (solid waste) will need to be contained for a long time. It is essential to prevent toxic elements and auxiliary contaminants from being transported into the environment. With the help of preventive monitoring tools, tailings dams will be under control, which facilitates the lithium remining phase, which is extremely profitable in this industry.

2. All processes require pumping and disposal of brine and actions to remove lithium from the brine. Waste liquids must be injected back into the ground – the use of non-waste liquids is avoided.

3. Dust and emissions of volatile contaminants need to be carefully evaluated. Generally, the recovery of lithium from dams requires sulphuric acid, which will require monitoring actions to minimise the release of sulphur dioxide into the air.

4. Data about lithium mining monitoring systems should be made public and available online. Global regulations establish that mines need to be operated safely as a fundamental priority to minimise adverse impacts on workers.

5. The long-term consequences of the mine will mainly be determined by whether it is properly closed and reclaimed. Tailings dams should be monitored regularly, producing data on the actual status of the closed mine.

Lithium tailings dams under control

The de-characterisation of lithium dams is an extremely delicate process that requires the use of monitoring technologies to be carried out safely. This undertaking is regulated by a protocol created in 2020 from an initiative by the United Nations Environment Programme (UNEP), the International Council on Mining and Metals (ICMM) and the Principles for Responsible Investment (PRI). The framework for the safety of lithium dams – including those that will not be de-characterised – is the Global Industry Standard Tailings Management. The goal is to manage the entire life cycle of lithium tailings deposits.

Compliance with the GISTM principles is supported by data generated by monitoring platforms that proactively and predictively measure critical factors. This includes checking the tension of the concrete walls, the water level in the dam, the temperature of the tailings in the dam, whether there have been movements in the tailings, whether the dam has produced noise, etc.

The success of lithium mining in Brazil depends on predictive monitoring of an extremely critical environment being taken into account from the outset of the mine project. A 2022 study by consultancy Mordor Intelligence indicates that the market for connectivity and monitoring solutions for the global mining industry is expected to reach 24 billion dollars by 2026.

Integrated OT and IT monitoring

The fact that the mine is a hostile and very expensive environment – an autonomous truck for use in mines can easily cost millions of reais – requires this sector to advance in connectivity between OT and IT sectors. In a lithium mine, a data centre will process data produced throughout the extraction chain, from pump pressure, volume in ore pipelines, to the useful life of equipment (OT data). For example, it will have a predictive view of equipment maintenance, which will prevent losses caused by unplanned interruptions. Another data centre, installed at the port, can deal specifically with commercial and administrative tasks linked to the export of the product (IT data).

One way to optimise the processes involved in mining and exporting lithium is to use digital environment monitoring solutions capable of unifying data on the entire mineral production and marketing chain in a single interface.

A report released by Delloite in early 2022 indicates that the Brazilian mining industry lags behind countries like Canada and Australia when it comes to relevant ESG issues. To help Brazil receive more and more investment, the exploitation of this white gold must be based on the best mining practices. This can be controlled in real time, 24×7, with the help of multiprotocol and convergent OT/IT monitoring platforms.

(*) Luis Arís is business development manager at Paessler LATAM.