Equipamento de seleção e processamento de escórias

Escória is a valuable by-product generated during metallurgical and industrial processes, including iron and steelmaking and the production of non-ferrous metals such as alumínio, cobre, chumboe zinco. Although slag has traditionally been treated as industrial waste, it often contains recoverable metals and useful mineral components. Slag sorting equipment and modern slag processing technologies can separate these valuable materials, improve resource recovery, reduce waste, and support more sustainable industrial production.

A typical slag sorting and processing process includes cooling and crushing, screening, magnetic separation, gravity separation, and, when necessary, additional separation technologies. The specific process and equipment configuration depend on the type, composition, particle size, and target products of the slag.

This article explains the composition and comprehensive utilization of slag, as well as the main steps of slag processing.

 

Composição da escória

A composição da escória depende de factores como o tipo de forno que a produz e o processo de produção. As escórias são constituídas principalmente por óxidos (por exemplo sílicaalumina, óxido de cálcio, óxido de magnésio) com pequenas quantidades de sulfuretos e metais. Entre estes, os óxidos de ferro têm um teor elevado, que pode atingir mais de 30% da massa total da escória. A escória também pode conter pequenas quantidades de elementos metálicos e não metálicos, incluindo cálcio, magnésio, alumínio, potássio, sódio e enxofre. No processo metalúrgico, a escória remove as impurezas nocivas do aço fundido, como o enxofre, o fósforo e os gases, através de reacções físico-químicas, e desempenha um papel de refinação. De acordo com os diferentes processos metalúrgicos, as escórias podem ser divididas em escórias de fundição e escórias de refinação. Além disso, as escórias também podem ser divididas em escórias alcalinas, escórias ácidas e escórias neutras, de acordo com a sua natureza.

 

 

O aproveitamento integral das escórias

A utilização global das escórias é um meio importante para alcançar uma economia circular. Para além da utilização dos componentes metálicos e não metálicos acima referidos, as escórias podem também ser utilizadas nos seguintes domínios

• Utilizado como fertilizante: Slag contains trace elements and minerals. After appropriate treatment, slag can be used as organic fertilizer to promote plant growth.
• Enchimento do terreno: After slag is harmlessly treated, it can be used as land backfill material, increasing land value.
• Produção de materiais de construção amigos do ambiente: As escórias podem ser misturadas com outros materiais para produzir materiais de construção amigos do ambiente, tais como tijolos de escória, betão de escória, etc.

 

Triagem de escórias

The treatment and recycling of slag are important links in industrial production. Slag sorting equipment is the key equipment in this process, and its efficient and accurate sorting ability is of great significance in improving resource utilization and reducing environmental pollution. The process steps of slag sorting equipment include preparação e pré-tratamento da matéria-prima, arranque e colocação em funcionamento do equipamento, processo de triagem das escórias, manutenção e reparação do equipamento e medidas de proteção ambiental e de segurança. Below, we will introduce the steps for slag sorting equipment in detail.

1. Raw Material Preparation and Pretreatment

After the slag is collected from the production line, it is transported to the separating area through special conveying equipment. Before formal separation, the slag needs to be pre-treated, including cooling, crushing, screening, and other steps to ensure that the slag’s particle size meets the separating equipment’s requirements. This link helps to improve separation efficiency and reduce equipment wear.

Cooling

Hot slag must be cooled to a suitable temperature before it enters downstream processing equipment. Cooling methods depend on the slag type and plant design.

Trituração

Crushing reduces large slag lumps to a more manageable particle size and helps liberate metallic particles from the surrounding mineral matrix.

Jaw crushers, cone crushers, impact crushers, and other equipamento de trituração may be selected according to the material characteristics and required particle size.

 

 

Rastreio

Screening separates slag into different particle-size fractions. This improves the efficiency of subsequent sorting equipment because different particle sizes may require different separation conditions.

 

2. Equipment Startup and Commissioning

After confirming that the slag is ready, start the slag sorting equipment. Before starting the equipment, perform the necessary debugging work, including checking whether the equipment components are intact, adjusting the sorting parameters, and so on. After the debugging is completed, the equipment enters the standby state, waiting for the input of slag.

3. Slag Sorting Process

Alimentação

A escória pré-tratada é alimentada uniformemente no equipamento de separação através do alimentador. Para garantir o efeito de separação, a velocidade de alimentação deve ser ajustada de acordo com a capacidade de processamento do equipamento.

Separação

After the slag enters the sorting equipment, it will be subjected to a variety of forces (such as gravity, magnetism, airflow, etc.) inside the equipment, so as to realize the effective separation of different components. In the process of separation, the equipment will automatically adjust the sorting conditions according to the preset parameters and the characteristics of the slag, in order to achieve the popular separating effect.

(1) Physical separation

Magnetic separation and gravity separation are used to separate metal and non-metal components by utilizing the responsiveness of metal to the magnetic field and the difference in material density. Magnetic separation can separate iron, nickel, and other magnetic metals, while re-election separates heavy and light components according to the density difference.

Separação magnética

Magnetic separation is one of the most widely used methods in slag processing, particularly when recovering iron-bearing or other magnetic metallic materials.

After crushing and screening, the slag passes through a magnetic separator. Magnetic particles are attracted to the magnetic field while non-magnetic materials continue through the separation system.

Depending on the material, magnetic separation may be used to recover:

• Metallic iron
• Iron-bearing particles
• Other magnetic materials

Separadores magnéticos can be configured at different stages of a processing line to improve metal recovery.

Separação por gravidade

When the target materials have significant differences in density, separação por gravidade can be used to further separate heavy and light fractions.

For example, after magnetic separation removes magnetic materials, gravity-based equipment may help concentrate heavier metallic particles from lighter mineral materials.

The appropriate equipamento de separação por gravidade depends on the particle size and density characteristics of the feed material.

 

 

 

(2) Chemical separation

Para os componentes que não podem ser completamente separados por métodos físicos, podem ser usados métodos químicos, utilizando reagentes químicos para reagir com componentes específicos e gerar substâncias solúveis ou insolúveis, realizando assim a separação.

Recolha e classificação

After separation is completed, slags of different compositions will be collected separately. Usually, the equipment will be equipped with multiple outlets so that different types of slag can be discharged separately. The collected slag can be further treated or recycled according to its nature.

 

Tratamento dos materiais após a separação

• Tratamento de componentes metálicos: Após a separação, os componentes metálicos podem ser refinados ou fundidos para extrair metais valiosos como o ferro, o cobre, o zinco, etc., que podem ser utilizados para produzir vários produtos metálicos.
• Tratamento de componentes não metálicos: Os componentes não metálicos, como o silicato, a alumina, etc., podem ser utilizados como materiais de construção ou matérias-primas de enchimento para o fabrico de tijolos e telhas, cimento, cerâmica e outros produtos.

 

4. Equipment Maintenance

In the long-term use of slag sorting equipment, it is inevitable that there will be wear and tear or failure. Regular maintenance and repair of equipment is crucial. This includes checking the wear and tear of various parts of the equipment, replacing damaged parts, and cleaning up the dust inside the equipment. Through effective maintenance and repair, the service life of the equipment can be extended, and the sorting efficiency can be improved.

 

5. Environmental Protection and Safety Measures

In the process of sorting slag, attention should be paid to environmental protection and safety. Equipment should be equipped with effective dust removal devices to reduce dust pollution; operators should comply with safety regulations and wear the necessary protective equipment to ensure personal safety.

 

Conclusion: Advancing Sustainable Industry Through Slag Recycling

Slag sorting equipment and modern processing technologies play a pivotal role in transforming industrial by-products into valuable resources. By effectively separating metallic and non-metallic components, these systems not only enhance resource recovery but also contribute to environmental sustainability by reducing landfill waste. The integration of physical and chemical separation methods ensures high efficiency, while advancements in cooling, crushing, and screening further optimize the process.

The recycled materials—metals for industrial reuse, mineral components for construction, and even nutrient-rich slag for agriculture—underscore the economic and ecological potential of slag utilization. Moving forward, continued innovation in sorting technologies and stricter adherence to safety and environmental protocols will further solidify slag recycling as a cornerstone of the circular economy.

By investing in these solutions, industries can achieve cleaner production, lower costs, and a reduced ecological footprint, paving the way for a more sustainable industrial future.