The angle between the bottom of the fermenter cone is not large or small. It has its own specifications. The angle between the bottom of the fermenter designed and manufactured by Zunhuang Company is the standard 70/60 degree included angle. The settled yeast in the fermentation broth occupies the smallest specific surface area at the bottom of the tank, and the friction between the yeast mud and the bottom wall of the tank is the smallest, which is conducive to the process discharge and cleaning of the beer yeast mud. When the fermentation tank is cleaned, the dirt attached to the bottom of the tank is conducive to cleaning. The cleaning time is short and the amount of cleaning sewage is small. At the same time, because the bottom of the tank (mostly yeast mud) is discharged cleanly, the residual amount is small. The pollution degree of cleaning sewage is low, which is conducive to environmental protection.