The ethanol-based acetic acid fermenter is a special aerobic deep-submerged ventilation fermentation equipment. Based on the oxidative fermentation principle of acetic acid bacteria, it takes ethanol (edible alcohol) as the main raw material, introduces sterile compressed air, and oxidizes ethanol into acetic acid through microbial fermentation.
It is the core host equipment for producing food-grade acetic acid and brewing vinegar, and is widely matched with corn deep processing industrial chains. Its main application scenarios are as follows:
1. Produce food-grade vinegar and acetic acid raw materials for food acidulant processing;
2. Support downstream citric acid production and other fine chemical fermentation processes as supporting acid raw materials;
3. Realize on-site supporting fermentation for corn ethanol deep-processing projects, reducing external raw material procurement costs.Compared with traditional solid-state fermentation, this liquid fermentation process features short production cycle, high ethanol conversion rate and high automation level. Strict control of dissolved oxygen, temperature, alcohol concentration and pH value is required during the whole aerobic fermentation process.
1. Feeding System (Three Independent Sanitary Feeding Ports)
- Main Material Inlet (Top): Used for feeding sterilized ethanol raw material and basic culture medium. Equipped with sanitary diaphragm valve to realize closed feeding and avoid miscellaneous bacteria contamination.
- Material Supplement Port (Side Wall): For automatic continuous ethanol supplementation during fermentation. It maintains stable alcohol concentration inside the tank to prevent inactivation of acetic acid bacteria, suitable for semi-continuous fermentation mode.
- pH Regulating Port: Automatic dosing of acid-base solution to stabilize the optimal growth environment for acetic acid bacteria.
2. Discharging System
- Bottom Main Discharge Port: For full tank discharging after batch fermentation completion, conveying fermented acetic acid liquid to subsequent filtration, decolorization and concentration processes.
- Intermediate Circulating Discharge Port: Special for semi-continuous fermentation. It discharges qualified acetic acid fermentation liquid quantitatively while supplementing fresh ethanol materials, realizing non-stop continuous production and improving equipment utilization rate.
- Aseptic Sampling Port: Real-time detection of alcohol content, acetic acid acidity and dissolved oxygen inside the tank to judge fermentation end point accurately.
3. Air Inlet & Exhaust Ports
- Air Inlet: Bottom distributed aeration structure with two-stage sterile air filtration, ensuring sufficient oxygen supply for high-strength aerobic fermentation.
- Exhaust Port: Equipped with mechanical defoaming device and tail gas sterilizing filter to prevent foam overflow and external bacterial cross-contamination.
1. Tank Body Structure
- Material: Inner tank adopts 316L sanitary stainless steel, outer jacket adopts 304 stainless steel; mirror polishing inside tank, no dead angle, meeting full CIP automatic cleaning requirements.
- Double-layer cooling & heating jacket: Realizes constant temperature control by circulating cooling water or hot water; supports 121℃ in-situ high-temperature sterilization with pressure-bearing design.
2. Core Process Auxiliary Systems
- Stirring System: Combined upper mechanical defoaming paddle and lower aeration stirring paddle. It strengthens gas-liquid mixing efficiency with low rotating speed and high dissolved oxygen, reduces foam generation and minimizes defoamer dosage.
- Constant Temperature Control System: Online temperature sensor linked with jacket cooling circulation system. The fermentation temperature is stably controlled at 30-35℃, the optimum temperature for acetic acid bacteria growth.
- Dissolved Oxygen & Tank Pressure Control System: Online dissolved oxygen electrode automatically adjusts air intake volume; maintains slight positive pressure inside the tank to block external miscellaneous bacteria invasion.
- Online pH Control System: Real-time monitoring and automatic acid-base dosing to keep stable fermentation environment.
- Automatic CIP Cleaning System: Built-in rotary spray ball for full-range tank cleaning without opening manhole, complying with food and pharmaceutical sanitary standards.
- Dual Defoaming System: Match mechanical defoaming and automatic electric defoaming probe to handle massive foam generated during ethanol fermentation.
3. Instrument & PLC Automatic Control System
- Matching detecting instruments: liquid level gauge, pressure gauge, temperature transmitter, dissolved oxygen sensor, online alcohol concentration detector.
- PLC touch screen automatic control: Supports preset fermentation curve, automatic recording and storage of full-process operation data including temperature, dissolved oxygen, air flow and pH value, with data traceability function.
- Safety protection devices: Over-temperature, over-pressure and high/low liquid level alarm system, plus safety valve for emergency pressure relief.
- Fermentation temperature: 30℃ ~ 35℃
- Working tank pressure: 0.02 ~ 0.05 MPa (slight positive pressure)
- Initial ethanol concentration: 5% ~ 8%
- Final acetic acid concentration: ≥9% ~ 10%
- Fermentation cycle: 36~48 hours for batch fermentation; continuous 24-hour operation for semi-continuous fermentation