Optionally, the microwave generation system includes a magnetron, a cooling device and a cast aluminum excitation cavity. One end of the magnetron is connected with the cast aluminum excitation cavity and the other end is connected with the cooling device. The cooling device includes an air cooling and/or water cooling device. The air cooling device includes an axial fan and a fan cover for heat dissipation of the magnetron. The dustproof plate for preventing foreign matters from entering the excitation cavity is disposed at the joint between the cast aluminum excitation cavity and the waveguide system. The water cooling device includes a water cooling container and a circulating water pipeline.

Optionally, the feed preheating section includes a feed tank. The material is conveyed between the feed tank and the microwave heating section through a screw pump. A flow meter is disposed in front of the microwave heating section and configured to accurately control the flow rate of liquids entering the microwave heating section. The feed tank is provided with jacket structure, and hot water with a predetermined temperature is provided in the jacket for heating the liquid material in the feed tank to the preheating temperature. The liquid materials are evenly stirred to improve the heating speed and uniformity, and also make all parts have the same initial temperature.