Equipos de clasificación y tratamiento de escorias

Escoria is a valuable by-product generated during metallurgical and industrial processes, including iron and steelmaking and the production of non-ferrous metals such as aluminio, cobre, plomoy zinc. 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.

 

Composición de la escoria

La composición de la escoria depende de factores como el tipo de horno que la produce y el proceso de producción. La escoria se compone principalmente de óxidos (por ejemplo, sílice, alúmina, óxido de calcio, óxido de magnesio) con pequeñas cantidades de sulfuros y metales. Entre éstos, los óxidos de hierro tienen un alto contenido, que puede alcanzar más de 30% de la masa total de la escoria. Las escorias también pueden contener pequeñas cantidades de elementos metálicos y no metálicos, como calcio, magnesio, aluminio, potasio, sodio y azufre. En el proceso metalúrgico, la escoria elimina las impurezas nocivas del acero fundido, como el azufre, el fósforo y los gases, mediante reacciones fisicoquímicas, y desempeña una función de refinado. Según los distintos procesos metalúrgicos, las escorias pueden dividirse en escorias de fundición y escorias de refinado. Además, según su naturaleza, las escorias también pueden dividirse en escorias alcalinas, escorias ácidas y escorias neutras.

 

 

Aprovechamiento integral de las escorias

La utilización integral de las escorias es un medio importante para lograr una economía circular. Además de la utilización de componentes metálicos y no metálicos mencionada anteriormente, las escorias también pueden utilizarse en las siguientes áreas:

• Se utiliza como fertilizante: Slag contains trace elements and minerals. After appropriate treatment, slag can be used as organic fertilizer to promote plant growth.
• Relleno de tierra: After slag is harmlessly treated, it can be used as land backfill material, increasing land value.
• Producción de materiales de construcción respetuosos con el medio ambiente: La escoria puede mezclarse con otros materiales para producir materiales de construcción respetuosos con el medio ambiente, como ladrillos de escoria, hormigón de escoria, etc.

 

Clasificación de escorias

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 preparación y pretratamiento de materias primas, arranque y puesta en marcha de equipos, proceso de clasificación de escorias, mantenimiento y reparación de equipos, y medidas de protección medioambiental y seguridad. 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.

Trituración

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 equipo de trituración may be selected according to the material characteristics and required particle size.

 

 

Proyección

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

Alimentación

La escoria pretratada se introduce uniformemente en el equipo de separación a través del alimentador. Para garantizar el efecto de separación, la velocidad de alimentación debe ajustarse en función de la capacidad de procesamiento del equipo.

Separación

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.

Separación 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.

Separación por gravedad

When the target materials have significant differences in density, separación gravimétrica 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 equipo de separación por gravedad depends on the particle size and density characteristics of the feed material.

 

 

 

(2) Chemical separation

Para los componentes que no se pueden separar completamente por métodos físicos, se pueden utilizar métodos químicos, utilizando reactivos químicos para reaccionar con componentes específicos y generar sustancias solubles o insolubles, realizando así la separación.

Recogida y clasificación

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.

 

Tratamiento de materiales tras la separación

• Tratamiento de componentes metálicos: Tras la separación, los componentes metálicos pueden refinarse o fundirse para extraer metales valiosos como hierro, cobre, zinc, etc., que pueden utilizarse para fabricar diversos productos metálicos.
• Transformación de componentes no metálicos: Los componentes no metálicos, como el silicato, la alúmina, etc., pueden utilizarse como materiales de construcción o materias primas de relleno para la fabricación de ladrillos y tejas, cemento, cerámica y otros productos.

 

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.