Different Types of Fermentation Tanks for Biochemical Production

 
Fermentation tank is widely used in bio-chemical production and is one of the important equipment. According to the different forms of mixing, fermentation tanks can be divided into three types: mechanical agitation fermentation tanks, bubble fermentation tanks, and liquid circulation fermentation tanks. Below we will have a detailed discuss of the advantages and disadvantages of various fermentation tanks and their scope of application.
 

Mechanical Agitation Fermentation Tank

Mechanical agitation fermentation tanks use mechanical agitators for mixing, and they are further divided into aerated agitation tanks and self-priming agitation tanks.
 

1. Aerated Agitation Tanks

 
Aerated Agitation Tanks, also known as universal fermentation tank, are the most commonly used microbial reactors in industry.

Advantages: Easy to control: the pH value and temperature of the fermentation solution are easy to control.
Suitable for continuous cultivation: It can carry out stable continuous cultivation for a long time.

Disadvantages: In the culture process of filamentous bacteria, cells are easy to be damaged, affecting the fermentation effect.
 

2. Self-priming Agitation Tank

​Self-priming agitation tank does not depend on air compressor for compressed air supply, but uses the negative pressure generated when the agitator rotates to draw in air. 

Advantages: Equipment simplification: Mixing and air supply are completed by mechanical agitator, reducing the dependence on auxiliary equipment.

Cons: This fermentation tank is not suitable for fermentation processes with high sterility requirements. Because the air enters the fermentation tank when stirring, it is not suitable for anaerobic bacteria fermentation.
 

Bubble Fermentation Tank

Bubble fermentation tanks use compressed air to provide the power needed for mixing and mass transfer and have the following characteristics.
 
Advantages:
Simple structure: the design is relatively simple, easy to manufacture and maintain.
Low cost: low cost, small power consumption, suitable for large-scale industrial applications.
Reduced damage: Less damage to filamentous bacteria during culture.
Disadvantages: Limited scope of application, generally suitable for low viscosity of culture medium, low solid content, low oxygen demand fermentation process.
 

Liquid Circulation Fermentation Tank

Liquid circulation fermentation tank realizes stirring and mixing through liquid circulation, which is divided into airlift fermentation tank and nozzle loop fermentation tanks.
 

1. Airlift Fermentation Tank

 
Advantages

Simple structure: similar to bubbling fermentation tank, there is no mechanical stirring, but there is an external circulation tube outside the tank.
Low cost: low cost, small power consumption.

Disadvantages: Generally suitable for low viscosity, low solid content of the culture medium, the scope of application is relatively narrow.
 

2. Nozzle Loop Fermentation Tank

Advantages

Efficient mixing: The mechanical pump is used to inject compressed air, forming a shear force field at the nozzle, dispersing the injected air into small bubbles in the liquid phase, and the mixing effect is good.
Wide range of application: Compared with the airlift fermentation tank, it has wider application, suitable for a variety of fermentation processes.

Disadvantages: The design is complex and the cost is relatively high.
                
Different types of fermentation tank have their own advantages and disadvantages in design and use, and the choice of the right type of fermentation tank needs to be determined according to the specific production needs. By understanding the characteristics of various fermentation tanks, the production process can be better optimized, and the fermentation efficiency and product quality can be improved.