How to Maintain Your Fermentation Tanks?

In the field of biological fermentation, fermentation tanks are core equipment. Their normal operation is crucial for production efficiency and product quality. To ensure that fermentation tanks can work stably in the long term, it is necessary to be familiar with the working principles of the equipment, the structure and performance of each component, as well as the functions of pipelines and valves. However, the maintenance and care of the fermentation tank are equally indispensable. Careful maintenance can not only ensure that the equipment is in the best condition but also effectively extend its service life.

Daily Inspection and Maintenance

Daily inspection and maintenance are the first line of defense to ensure the normal operation of fermentation tanks. During the operation of the equipment, the following key indicators should be closely monitored, and corresponding monitoring records should be kept.

1. System Pressure and Tank Pressure

System pressure and tank pressure are important parameters in the operation of fermentation tanks. Both excessively high and low pressures can affect the fermentation effect and even cause equipment damage. Therefore, it is essential to ensure that these pressures remain stable within the specified range. Regularly check the readings of the pressure gauges, and if any abnormalities are found, promptly investigate the causes, such as pipeline blockages or valve failures.

2. Agitation System and Temperature Control System

The agitation system and temperature control system are core components of fermentation tanks. The normal operation of the agitation system ensures the uniform mixing of the fermentation liquid, while the temperature control system maintains the required temperature conditions for fermentation. During daily operation, carefully listen to the sounds of the agitation motor and solenoid valves. If abnormal noises are detected, it may indicate problems with the agitation shaft, bearings, or motor, and the machine should be stopped for inspection. At the same time, check whether the displayed parameters of temperature, dissolved oxygen, and pH match the set values. If there are deviations, adjust the relevant controllers.

3. Culture Liquid Color and Level

The color and level of the culture liquid are also important indicators reflecting the fermentation process. The normal color of the culture liquid is usually light yellow or brownish-yellow. If the color is abnormal, it may indicate problems in the fermentation process, such as contamination or metabolic abnormalities. Controlling the liquid level is equally important. An excessively high liquid level may cause overflow, while an excessively low level may affect the agitation effect and aeration volume. Regularly check the readings of the liquid level sensor to ensure its accuracy.

3. Valves, Pipe Fittings, and Interfaces

The sealability of valves, pipe fittings, and interfaces is crucial for the normal operation of fermentation tanks. During daily inspections, carefully observe these parts for any leakage. Leakage can not only lead to material loss but also introduce external contamination, affecting the fermentation effect. For any detected leakage points, promptly replace the sealing rings or repair the interfaces.

Comprehensive Inspection and Correction

In addition to daily inspection and maintenance, a comprehensive inspection and correction of the fermentation tank should be carried out every three months. This process requires more meticulous and comprehensive attention to ensure that all components of the equipment are in good working condition.

1. Power Off and Source Disconnection

Before conducting a comprehensive inspection and correction, it is necessary to cut off all power, water, and air (steam) sources. This is to ensure the safety of the operators and prevent accidents during the inspection process.

2. Inspection of Sealing Rings and Sealing Ends

Sealing rings and sealing ends are key components of fermentation tanks, and their sealing performance directly affects the operation of the equipment. Carefully inspect the condition of all sealing rings and sealing ends in the system, checking for permanent deformation, aging, scratches, or damage. If any problems are found, they must be replaced in a timely manner to prevent leakage and contamination.

3. Sterilizing Filters and Motor Carbon Brushes

The integrity of sterilizing filters is crucial for preventing contamination during the fermentation process. Check the filters for any damage or blockage, and replace them if necessary. At the same time, inspect the wear of the motor carbon brushes, as well as the commutator, bearings, couplings, and agitation system. Excessive wear of the carbon brushes can lead to a decline in motor performance and even damage the motor, so they need to be replaced regularly.

4. Electrical Controller Inspection

The electrical controller is the "brain" of the fermentation tank, and its normal operation is the basis for the equipment to run. Inspect all switches, buttons, electrical components, fixing screws, and nuts of the electrical controller, checking for any looseness or overheating. Loose connections can lead to poor contact, and overheating may be a sign of component damage. These issues should be addressed promptly.

Cleaning Methods

Cleaning of fermentation tanks is an important step to prevent contamination and ensure product quality. The tank and related equipment must be cleaned promptly after each fermentation and before reuse.

1. Preparations Before Cleaning

Before cleaning, remove the pH and DO electrodes and maintain them according to their requirements. Disconnect the quick connector of the air inlet rubber hose condenser and remove the rubber hose and connector from the air inlet filter. Remove the top cover along with the agitator vertically upward and place it horizontally on a flat surface, padded to avoid collisions with the shaft and impeller.

2. Cleaning Process

When cleaning the tank, it can be done in conjunction with water and air supply, motor agitation, and heating. If multiple water changes still cannot clean the tank thoroughly, open the top cover and use a soft-bristled brush to scrub the internal components of the tank. During the cleaning process, pay attention to protecting the electrical components and electrode interfaces to prevent water ingress and dampness. Use a neutral detergent to scrub the tank and all internal components to ensure thorough cleaning.

3. Post-Cleaning Inspection and Installation

After cleaning, carefully inspect the O-ring seals of the tank and outlet valve, and replace them if damaged or aged. When reinstalling, pay attention to tightening the tank cover fastening screws evenly to ensure an even gap between the tank and the tank seat. For glass fermentation tanks, be especially careful during disassembly and assembly to avoid collisions. When tightening the tank cover fastening screws, apply even force to prevent damage to the glass tank body.

Maintenance of Agitation System

The agitation system is one of the key components of fermentation tanks, and its normal operation is crucial for the fermentation process. The agitation system includes the agitation shaft, impeller, mechanical seal, bearings, couplings, and motor.

1. Daily Maintenance

During daily operation, regularly check the operation of the agitation shaft, the heating condition of the motor, and the emission of abnormal noises. At the same time, inspect whether any bolts are loose. Annually, check the wear of the mechanical seal to ensure its normal operation and avoid contamination risks due to poor sealing. If a double-faced mechanical seal is used, pay attention to the level of sterile water frequently. If the liquid level drops, it indicates a leak in the seal, which should be addressed immediately after fermentation.

2. Periodic Inspection

Annually, inspect the wear of the oil seal and motor carbon brushes, as well as the wear of the oil seal and bearings. Wear of these components can lead to a decline in the performance of the agitation system and even damage the equipment. Regular inspection and replacement of these worn parts can effectively extend the service life of the agitation system.

Maintenance of Sterilizing Air System

The sterilizing air system is an important part of fermentation tanks, and its normal operation is crucial for ensuring a sterile environment during the fermentation process. The sterilizing air system includes an air compressor, coarse filter, fine filter, diaphragm valve, and air distributor.

1. Daily Maintenance

During daily operation, pay attention to the operation of the air compressor. During fermentation, the condensate valve of the air receiver should be drained twice a day to prevent water accumulation from damaging the equipment. Maintenance and care of the filters are also very important. The sterilization temperature should be controlled below 125℃, as excessively high temperatures can cause the adhesive of the filter material to脱落, rendering the filter ineffective.

2. Filter Replacement

Since air contains a large amount of dust, the micro-pores of the filter element will gradually clog after a period of use. This not only increases resistance, causing insufficient air flow and increased pressure drop, but also introduces contamination. Therefore, when the air flow is found to be less than 1.5 times the volume of the tank, the filter should be replaced. Due to the significant differences in air quality in different regions, the service life of the filter can generally reach more than six months, but the specific replacement time should be judged according to the actual situation.

3. Air Distributor Cleaning

After each fermentation, the air distributor should be cleaned. If the nature of the fermentation liquid is similar to water, water can be added to the tank and then compressed air can be passed through for cleaning. If the fermentation liquid is viscous or contains fine particles, it is best to remove the air distributor, unscrew the plug, and rinse it with water, ensuring that the small holes are unobstructed for air passage.

Maintenance of Steam System

The steam system is an important part of fermentation tanks, and its normal operation is crucial for ensuring temperature control during the fermentation process. The steam system includes a steam filter, steam pipeline valves, etc.

1. Daily Maintenance

During use, regularly ensure the constancy of steam pressure. Fluctuations in steam pressure can lead to unstable temperatures during fermentation, affecting the fermentation effect. At the same time, the filter element of the steam filter will become clogged after a period of use and needs to be replaced regularly.

2. Operational Precautions

During operation, be careful not to fully open the steam valve at once. This can impact the filter element of the steam filter, and in severe cases, it can break the filter element or cause leakage, rendering the filter ineffective. Therefore, when opening the steam valve, do so slowly to ensure that the steam enters the system smoothly.

Conclusion

The maintenance and care of fermentation tanks is a systematic task that requires users to invest sufficient attention and effort during daily operation. By regularly inspecting and maintaining the equipment, conducting comprehensive inspections and corrections, using correct cleaning methods, and carefully maintaining each key system, the service life of fermentation tanks can be effectively extended, and the equipment can be kept in optimal operating condition. It is hoped that the introduction in this article will help users better master the maintenance skills of fermentation tanks, improve the operating efficiency of the equipment, and enhance product quality.