How Chilean steelmaker Aceros AZA contributes to the circular economy

Aceros AZA has become the main player in Chile’s steel industry after Huachipato, a subsidiary of the CAP group, decided to close its mill due to financial losses.

Although the main product of AZA is not bars to manufacture grinding balls for mining, as was the case for Huachipato, its rebars and rolled products are widely used in industrial structures and tunnels at mining sites.

Furthermore, its formula based on recycling to produce ‘green steel’ makes it a key supplier for miners, who must not only increase their production but also their sustainability profiles and transform their waste into useful resources.

To discuss scrap, steel reuse, the circular economy, the market and the value of mining waste, BNamericas interviews Juan Antonio Osses, metals purchasing manager at AZA.

BNamericas: How much scrap do you process annually and what are production expectations for this year?

Osses: We process more than 500,000t/y of scrap, which allows us to produce up to 520,000t/y of green steel. In the coming years, we hope to increase our production capacity by 10% to reach 580,000t/y.  

In the long term, we hope to continue improving our scrap processing capacity to continue being one of the most important strategic allies for industries such as mining, in their goal to get closer to a circular economy.

BNamericas: What are the main materials for recycling at AZA's plants?

Osses: We recycle ferrous scrap as raw material for the manufacture of green steel, which comes from various sources, including the mining, construction, industrial and domestic sectors. Around 20% of the scrap we process is of household origin, collected through a network of more than 13,000 recyclers that operate throughout the country.

Using 100% scrap as raw material and incorporating renewable electrical energy in our processes allows us to produce green steel and position it as one of the world's lowest carbon footprints.

BNamericas: What AZA products are most required by mining companies in Chile?

Osses: The mining industry mainly consumes our concrete reinforcing bars, which are used in new facilities or expansions. Another widely used element is our Saferock 2.0 fortification and containment system, which is a key solution for the structural and security requirements of the sector. We also provide recycling services at the site, allowing mining companies to recover value from the materials in their operations and contribute to the circular economy.

BNamericas: What materials from Chilean mining operations do you recycle in AZA's production processes?

Osses: The metal waste generated in Chilean mining operations is essential for our manufacturing processes. Among the most used materials are grinding ball scrap, which we recover from historical stockpiles, eliminating environmental liabilities and revaluing the metallic material. 

Likewise, we carry out the disassembly of mining equipment and machinery such as shovels, trucks, hoppers, shovel cables and other types of equipment, along with the disassembly service of complete production plants.

These activities enable efficient recovery of metallic materials and support the sustainability of mining operations. That is, we help them transform their waste into high-quality steel products that are then essential for their own operations.

BNamericas: How is the trend in green steel consumption by the mining industry advancing? 

Osses: Green steel consumption is growing in industries like mining, which are increasingly recognizing the need to reduce their environmental impact. However, the level of adoption is gradual. So, our focus is on educating the market about the benefits of choosing sustainable products and how green steel not only reduces the carbon footprint but also contributes to the construction of sustainable projects. Other types of steel on average exceed our carbon footprint by up to 10 times.

BNamericas: How did the steel market perform last year and what prospects do you have for 2025?

Osses: In 2024 the steel market remained stable compared to 2023, although far from the levels of previous years, mainly due to the low dynamism of key sectors such as construction. Another factor that has an effect is the competition from imported products, which has led several Latin American countries to impose special tariffs on imported steel to level the playing field in their local markets.

However, we are convinced that the consolidation of sustainable projects and green steel will allow us to maintain stable and growing demand. For 2025 and the coming years we see a similar panorama, although we project a slight recovery, driven by better financing conditions in the real estate market and a greater preference for products with a low carbon footprint. Although it all depends on the macroeconomic challenges that come.

BNamericas: What is the importance of having participated in the recycling project for end-of-use tires (ELT), led by Proindar and Arrigoni Ambiental?

Osses: We are prepared to continue supporting ELT recycling. Our focus is on recovering value to materials and consolidating sustainable solutions that allow waste such as ELT to be integrated into industrial processes. In addition to reducing environmental liabilities, it promotes a positive impact on the industry and the environment. We'll continue working on strategic alliances to develop projects like this.

BNamericas: What is AZA's contribution to reducing emissions at the national level?

Osses: We have one of the lowest carbon footprints in the industry, with only 0.24t of CO2eq per ton of steel produced. In addition, we have implemented several innovative initiatives to continue reducing our footprint. One of our latest investments, which will be opened in March, is our shredder fragmentation plant.

[Editor's note: The plant is being built by AZA at its facilities in Colina, north of Santiago. The scrap shredder and separator will use renewable energy, recirculated water, acoustic barriers to mitigate noise and filters to capture dust emissions. The investment amounts to about US$26mn.]