The biological turntable is a sewage treatment device recommended by China's "Water Supply and Drainage Design Manual". It is a wall-mounted rotary treatment equipment that uses multiple sets of discs immersed in the sewage to allow microorganisms to attach and grow, forming a bio-rich biofilm, to degrade organic matter in wastewater. Biofilm is one of the sewage treatment methods. It is a microbial community that grows and multiplies by adhering to the solid surface medium. The microorganisms attached to the surface of the solid medium have strong adaptability to changes in water quality and quantity and are conducive to the formation of a stable ecosystem for microorganisms. With many types of inhabiting microorganisms, the treatment efficiency is low, and the amount of sludge as degradation products is small.