What are the basic requirements of a biological fermenter? Biological fermenter Fermenter is a sealing pressure equipment, the main components include tank, agitator, shaft seal. Debubbler, coupling, intermediate bearing air blowing tube (or air ejector), baffle, cooling device, manhole, mirror, pipeline, etc. Fermenters are usually equipped with two sets of stirring blades spaced about three times the diameter of the stirring blades. For large or tall tanks (diameter ratio over 10), three or more sets of stirring blades may be installed.

Biological fermenter must meet the following basic requirements:

(1) The biological fermenter should have an appropriate height to diameter ratio. The height to diameter ratio of fermenter is generally (205~4):1:.

(2) The fermenter should be able to withstand fixed pressure. Because the fermenter has certain pressure and temperature during disinfection and normal operation, the components of the tank should have certain strength and be able to withstand fixed pressure.

(3) The stirring device and ventilation device of the biological fermenter should be able to make the bubbles disperse fine pieces, fully mix the gas liquid, ensure the dissolution of oxygen, and improve the utilization rate of oxygen.

(4) Fermenter should have heating and cooling device, and should have enough cooling area. Microbial growth and metabolism process releases a lot of heat. In order to control the temperature required at different stages of the fermentation process, the fermenter should have sufficient cooling area.

(5) Biological fermenter should be polished to minimize dead corners and ensure thorough sterilization.

(6) The mixer shaft seal should be tight to minimize leakage.

Microorganisms require oxygen for reproduction and anaerobic fermentation, and usually use air as a source of oxygen. The air contains a variety of microorganisms, these microorganisms with the air into the culture medium, under appropriate conditions, they will multiply, consume a large number of nutrients, and produce a variety of metabolic products, interfere with or even destroy the normal progress of the scheduled fermentation, the titer of fermentation products, production decline, and even cause a complete failure of fermentation and other serious accidents. Therefore, air sterilization has become an important link in the anaerobic fermentation engineering. There are many methods of sterilizing, such as filtration sterilizing, heat sterilization, electrostatic sterilizing, radiation sterilization, etc., but the sterilizing effect, equipment conditions and economic conditions of various methods are different. The required degree of sterilization is determined according to the requirements of the fermentation process, which should not only achieve the effect of sterilization, but also simplify the sterilization process as far as possible, so as to reduce the equipment investment and power consumption of normal operation.