Die casting is a common manufacturing process in the metal processing industry, which produces complex and precise metal components. However, during the die casting production process, the generation of waste residues is inevitable. These residues include used metal bath, slag, overflow trimmings, and more. Proper and effective treatment of these residues is not only related to environmental protection but also involves the efficiency of resource recycling and reuse. Let’s discuss the methods for treating waste residues from die casting machines, helping industry professionals understand how to achieve resource utilization and harmless disposal of waste.

1、Classification and Separation of Waste Residues

Firstly, the treatment of waste residues needs to start from the source by classifying and separating different types of residues. This includes separating recyclable materials like metal bath and overflow trimmings from actual slag. Through classification, valuable metal materials can be maximally recovered while reducing potential harm to the environment.

2、Melting Recycling Method

For waste residues with a high proportion of metal content, such as used metal bath and trimmings, melting recycling can be employed to reintroduce them into the production process. This method involves heating the residues in a furnace to a high temperature, melting the metal components, and then skimming off the impurities on the surface, resulting in relatively pure metal liquid for reuse in die casting production.

3、Mechanical Sorting Method

For solid waste residues, such as solidified metal bath and overflow trimmings, mechanical sorting can be utilized. The residues are crushed into small pieces using crushers, and then magnetic separators or air separators are employed to separate the metal from non-metal parts, facilitating subsequent treatment and recycling.

4、Chemical Treatment Method

Some residues may contain hazardous substances that require chemical treatment for conversion or stabilization. For example, by adding specific chemical reagents, harmful heavy metal ions can be transformed into insoluble compounds, thereby reducing their environmental hazards.

5、Thermal Decomposition Method

The thermal decomposition method can be employed for residues with a high content of organic substances. By subjecting the residues to high-temperature heating, organic materials are decomposed into gas and ash, from which energy can be recovered, and the final amount of waste is reduced.

6、Biological Treatment Method

In addition to physical and chemical methods, biological treatment can be a viable option. By utilizing the action of microorganisms, organic substances in the residues can be decomposed into harmless substances. This method is environmentally friendly and relatively low-cost but may have longer treatment cycles.

7、Landfilling

For residues that cannot be recycled or treated, safe landfilling is the final option. This needs to be carried out in compliant landfill sites that meet environmental requirements, ensuring that the residues do not contaminate groundwater and soil.

8、Comprehensive Utilization

In practical operations, it is often necessary to combine multiple methods to treat waste residues. For example, most of the metal can be recovered through melting recycling, and then the remaining non-metal parts can undergo mechanical sorting or chemical treatment, followed by safe landfilling of the unprocessable residual waste.

9、Conclusion

The treatment of waste residues from die casting machines is a comprehensive engineering task that requires selecting appropriate treatment methods based on the nature and composition of the residues. Through effective classification, recovery, and treatment, it is possible to reduce environmental pollution and improve resource utilization, achieving sustainable development. With increasingly stringent environmental regulations and continuous technological advancements, future methods for waste residue treatment will become more diverse and efficient, aiming to achieve a dual enhancement of environmental and economic benefits.