Fermenter is a kind of bioreactor, which refers to a device system that provides a suitable reaction environment for living cells or enzymes for cell proliferation or production. It also provides a suitable growth environment for the growth and reproduction of bacteria, and promotes the production of products required by bacteria.Fermenter can be divided into different types according to different classification methods.

• Classified according to the needs of microbial growth and metabolism.

Aerobic fermenter: Aerobic fermenter is suitable for the fermentation of antibiotics, enzymes, yeast, amino acids, vitamins and other products. Their common point requires strong ventilation and stirring to improve the mass transfer coefficient of oxygen in the fermentation liquid.
Anaerobic fermenter: Anaerobic fermenter is suitable for the fermentation of acetone butanol, alcohol, beer, lactic acid and other anaerobic products. Their common point is that they do not need ventilation.

• Classification according to the characteristics of fermenter equipment.

Mechanical stirring ventilated fermenter: including circular fermenter, such as five type fermenter, Venturi tube fermenter, non circular ventilated fermenter and self-priming fermenter.
Non mechanical stirring ventilated fermenter: including circular air lift and liquid lift fermenter, as well as non circular tube type and jet type fermenter.
These two types of fermenters use different means to fully mix the gas, solid and liquid phases in the fermenters, so as to meet the oxygen demand of microbial growth and product formation.

• Classification by volume

It is generally believed that the fermenters below 500L are laboratory fermenters, 500-5000L are pilot fermenters, and those above 5000L are fermenters of production scale.

This is the classification of fermenters. The main uses of fermenter vary greatly according to the varieties, processes and application fields of fermenter. Cleaning of fermenters is very important, and the cleaning methods are similar for different types of fermenters.
Fixed cleaning ball: The traditional fixed cleaning ball is the most commonly used cleaning device. The fixed cleaning balls have different types, sizes and cleaning capacities. The fixed cleaning balls can spray the cleaning solution to the tank wall for simple fixed cleaning.

Rotating cleaning ball: The way and effect of rotating cleaning ball is better than that of traditional fixed cleaning ball. The nozzle of the rotary cleaning ball sprays on the tank wall in an irregular manner. In terms of the combination of cleaning method and mechanical impact force, it uses less water, consumes less chemicals and can remove residues in a short time than the fixed cleaning ball.

Double cycle cleaner: double cycle cleaning can effectively clean the fermentation tank. The spraying forms include middle up spraying, middle down spraying, full spraying, spraying within 360 degrees, high cleaning efficiency, low water consumption, energy consumption and chemical agent consumption; Sanitary structure, self-lubricating with cleaning fluid, can wash the tank at any angle.
The fermenter still needs to be cleaned after being used for a period of time. Cleaning the fermenter can ensure the product quality and prolong the service life of the fermenter equipment.

The outstanding difference between fermenters and other industrial equipment is the high requirements for pure seed culture, almost to a very demanding degree. Therefore, the tightness of the fermenter, the operation of a high degree of reliability is a significant feature of the fermentation industry. Modern fermentation industry in order to obtain greater economic benefits, fermenter tend to be more large-scale and automated development.