Microwave is a relatively safe heating technology because it does not belong to radioactive rays and has no harmful gas emissions. At the same time, it should be pointed out that inappropriate microwave radiation will also have a systemic adverse effect on the human body, especially the lens of the eye, stomach, intestines and other organs with poor blood circulation are more vulnerable to damage. Therefore, microwave leakage and microwave radiation of the instrument should be prevented during the experiment. Microwave heating technology Different from the traditional heating method, it generates "internal friction heat" through the high-frequency reciprocating movement of dipole molecules inside the heated body to raise the temperature of the heated material. Without any heat conduction process, the internal and external parts of the material can be heated at the same time, and the heating speed is fast and uniform, Only a fraction or a fraction of the energy consumption of the traditional heating method can achieve the heating purpose. From the theoretical analysis, the amount of heat generated by substances in the microwave field has a great relationship with the types of substances and their dielectric properties, that is, microwave has the characteristics of selective heating of substances.

At present, the application research of microwave in metallurgical process involves microwave enhanced leaching, microwave assisted extraction, microwave carbothermal reduction microwave drying , microwave sintering and other fields.

　　 Microwave high temperature The heating is even and very fast. Microwave can heat the heated material inside and outside at the same time, avoiding the cold center phenomenon caused by traditional heating. The heat loss is small, and the utilization rate of heat energy is high, microwave heating The big feature is that the floor area is small, thus avoiding high ambient temperature. However, the working conditions of workers have been greatly improved. Generally, industrial heating equipment is relatively large, covering a lot of land, and the ambient temperature is also relatively high. The working conditions of operators are poor and the intensity is high. Compared with conventional electric heating, microwave heating can generally save 30%~50% of electricity. Low temperature sterilization is usually carried out at high temperature. However, microwave technology can kill bacteria in a closed environment at extremely low temperature by using double sterilization, which is also a heating method to ensure that nutrition is not affected. It is highly recommended in the food processing industry.