Research on Fine Maintenance Process of Fermentation Equipment and Future Technology Iteration Direction

Raw pulp fermentation serves as a core process in the processing of food, beverages and biological products. Material conversion is realized through natural microbial fermentation without blending or secondary processing, imposing stringent requirements on production environment, equipment status and process stability. As the core carrier for process implementation, raw pulp fermentation equipment consists of key assemblies including fermentation tank, temperature control system, dissolved oxygen regulation system, sensor detection module, pipelines, valves and aseptic guarantee system. Its operational stability, cleanliness and accuracy directly determine the flavor, batch-to-batch quality consistency and production safety of raw pulp products. Compared with conventional processing equipment, raw pulp fermentation equipment operates for long periods under high-humidity, organic-rich and microbially active working conditions, which readily trigger material residues, component aging, parameter drift, microbial contamination and other defects. Therefore, establishing a standardized and regular maintenance system to effectively avoid operational risks, while upgrading the equipment system in line with industrial technological iteration trends, constitutes the core prerequisite for stabilizing raw pulp fermentation processes, extending equipment service life and cutting production energy consumption. This paper systematically introduces the standardized maintenance system of raw pulp fermentation equipment, analyzes common operational and maintenance problems, and conducts in-depth research on future technological development directions of the industry.

I. Standardized Graded Maintenance System for Raw Pulp Fermentation Equipment

The core objective of raw pulp fermentation equipment operation and maintenance is to maintain an aseptic production environment, ensure precise and controllable process parameters, slow down component aging and prevent unplanned shutdown failures. Differentiated from general mechanical equipment, its maintenance activities shall combine fermentation batch cycles, equipment structural characteristics and microbial production requirements to build a four-level graded system covering daily inspection, batch maintenance, monthly special maintenance and annual overhaul, so as to realize full-cycle and all-aspect operation control.

(I) Daily Inspection & Maintenance

Daily inspection is the basic measure to prevent sudden failures, focusing on real-time equipment operating status and basic working parameters. Before startup, operators shall fully check the tightness of equipment pipelines, valves and flange connections to detect potential air, liquid and seepage leakage, and eliminate microbial contamination and process runaway caused by sealing failure. During operation, core parameters such as tank pressure, temperature, dissolved oxygen and stirring speed shall be monitored in real time; the consistency between sensor readings and process standards shall be verified, and parameter drift shall be corrected timely. Meanwhile, the operating status of the stirring system and transmission components shall be inspected for abnormal noise, jamming, abnormal vibration and other anomalies, to confirm that cooling, heating and ventilation systems function normally. After equipment shutdown, dust and stains on equipment surfaces shall be cleaned promptly, and the equipment room shall be kept ventilated and dry to mitigate metal corrosion and circuit aging induced by humid environments.

(II) Closed-Loop Batch Maintenance

Upon completion of each raw pulp fermentation batch, closed-loop cleaning, sterilization and maintenance shall be implemented immediately to completely eliminate hidden risks of microbial proliferation and scaling corrosion arising from material residues, which acts as a key link to guarantee stable product quality per batch. First, residual feed liquid and fermentation waste liquid inside the tank shall be drained. A staged cleaning process is adopted: warm water flushing removes surface organic residues, food-grade alkaline detergent dissolves stubborn organics such as protein and saccharides, and acidic detergent is subsequently applied to eliminate mineral deposits including water scale and fermentation scale on inner walls of tanks and pipelines. During cleaning, the coverage of spray balls shall be checked emphatically to avoid blind cleaning zones such as tank dead corners, pipeline elbows and valve cavities. After cleaning, SIP (Steam-in-Place) sterilization shall be performed strictly in accordance with standard temperature and pressure parameters for thorough inactivation to maintain the aseptic state of the equipment system and lay a solid foundation for subsequent batches. In addition, batch maintenance shall synchronously inspect sealing elements; O-rings and gaskets with hardening, cracks or aging deformation shall be replaced timely to sustain stable sealing performance of tanks and pipelines.

(III) Monthly Special Maintenance

Monthly maintenance targets special inspection of wearing parts, precision sensing modules and auxiliary systems of the equipment. For moving components including stirring bearings, transmission chains and reducers, food-grade compliant grease shall be added regularly to reduce mechanical wear and cut operating noise and energy consumption. Core sensors for temperature, pH, dissolved oxygen and pressure shall be fully calibrated: pH electrodes shall be precisely calibrated using standard buffer solutions, dissolved oxygen electrodes shall undergo zero and full-scale calibration, while temperature and pressure sensors shall be verified at multiple points to ensure accurate and reliable sensor data and prevent fermentation process runaway caused by data deviation. In parallel, the patency of cooling coils and heat exchange pipelines shall be fully inspected, blocked points unclogged and wall scale removed to secure heat exchange efficiency of the temperature control system. Functional tests shall be conducted on all equipment valves and control switches, and aged circuits and loose connectors shall be overhauled to guarantee sensitive control and stable equipment operation.

(IV) Annual Comprehensive Overhaul

Annual comprehensive overhaul refers to systematic equipment maintenance requiring shutdown for full disassembly inspection and optimization upgrading. First, tanks, pipelines and heat exchange systems shall be completely disassembled and cleaned. Weld seams and inner wall flatness of stainless steel tanks shall be inspected to detect pitting corrosion, intergranular corrosion, microcracks and other hidden defects. Local rust spots and corroded areas shall be polished and repaired with dedicated food-grade rust removers to avoid structural damage of equipment. Comprehensive replacement of long-serving sealing elements and wearing parts shall be carried out, and severely aged pipelines and valves shall be replaced as a whole. Complete machine pressure test, tightness test and aseptic performance test shall be implemented to verify that the equipment pressure bearing capacity and aseptic performance meet standards. Meanwhile, control system programs and parameter thresholds shall be optimized and calibrated, equipment operation data ledgers updated, and maintenance and component replacement plans for the next year formulated combined with annual operating conditions. For long-term idle equipment, thorough cleaning and drying shall be completed, food-grade anti-rust protective agent sprayed for dust-proof and anti-corrosion preservation, and regular ventilation inspection performed to prevent mold growth and equipment corrosion.

II. Common Misconceptions in Equipment O&M and Risk Control Measures

In actual operation and maintenance of raw pulp fermentation equipment, non-standard operations and inadequate maintenance tend to aggravate equipment degradation, reduce product quality and trigger production safety hazards. Four typical O&M misconceptions should be avoided, and targeted risk control mechanisms shall be established. First, avoid the misconception of running equipment with faults. In some production scenarios, operators overlook minor faults such as slight air leakage, abnormal noise, liquid seepage and small parameter drift without timely maintenance. Long-term faulty operation accelerates component wear, expands the scope of equipment failure, greatly increases subsequent maintenance costs, and may easily cause microbial contamination and abnormal fermentation, leading to batch product losses. Second, avoid non-standard cleaning and sterilization. Problems such as insufficient detergent concentration, inadequate sterilization temperature and pressure, and omitted cleaning dead corners result in organic and microbial residues, disrupting the microecological environment of raw pulp fermentation and impairing product flavor and quality stability. Third, avoid inadequate water quality management. Long-term adoption of hard water for production and cleaning leads to continuous scaling inside tanks and pipelines, reducing heat exchange efficiency and cleaning effect. Meanwhile, scale impurities indirectly degrade raw pulp quality. Fourth, avoid the misconception of prioritizing repair over prevention. Reliance on remedial maintenance after failures while neglecting routine preventive maintenance keeps equipment failure rate at a high level and undermines production continuity. To tackle the above problems, manufacturers shall establish standardized O&M ledgers, define maintenance standards, cycles and responsible persons for each procedure, strengthen professional training for operators, standardize full-process operations of cleaning, sterilization, calibration and inspection, adhere to the O&M principle of "prevention first, integration of maintenance and repair", and reduce equipment failure risks and quality hazards from the source.

III. Future Technological Development Trends of Raw Pulp Fermentation Equipment

With the standardization, intellectualization and green upgrading of the food processing industry, together with rising requirements for refined quality, stability and safety of raw pulp products, traditional extensive fermentation equipment can no longer meet high-end production demands. Future raw pulp fermentation equipment will be iteratively upgraded along five core directions: intelligent precision control, integrated aseptic design, green energy conservation, modular flexible production and full-process traceability management, realizing intelligent equipment maintenance, refined process control and standardized production.

(I) Popularization of Intelligent Sensing and Fully Automatic Precision Regulation Technology

Traditional fermentation equipment mostly relies on manual monitoring and manual adjustment, featuring low parameter control accuracy and obvious hysteresis, which easily cause batch quality differences. Future equipment will be fully equipped with high-precision intelligent sensing modules to realize real-time dynamic collection, automatic analysis and closed-loop regulation of multi-dimensional parameters including pH, dissolved oxygen, temperature, pressure, stirring speed and fermentation liquid level. Equipped with industrial Internet of Things systems and embedded algorithms, the equipment can automatically select optimal process parameters according to microbial metabolic characteristics at different raw pulp fermentation stages, dynamically adjust temperature control, dissolved oxygen and stirring speed, thoroughly resolving parameter fluctuations induced by manual regulation. Meanwhile, the system supports automatic storage of operating data, real-time alarm of abnormal data and intelligent fault diagnosis, greatly lowering manual O&M costs and improving process stability and product consistency.

(II) Mainstream Adoption of Integrated Aseptic Design

Aseptic assurance is the core of raw pulp fermentation production. Traditional equipment features complicated pipelines and numerous connections, prone to cleaning dead corners and sealing risks. New-generation raw pulp fermentation equipment will adopt integrated structural design to simplify pipeline layout and reduce connecting points such as flanges and valves, lowering risks of sealing failure and contamination. The equipment integrates automatic CIP cleaning and SIP sterilization systems to realize closed-loop automatic operation covering cleaning, sterilization, feeding, fermentation and discharging without manual intervention, effectively avoiding contamination risks from manual operation. Meanwhile, tank interiors adopt mirror polishing and dead-corner-free structural design paired with adjustable spray cleaning systems to improve cleaning and sterilization performance and guarantee an aseptic environment throughout fermentation.

(III) Iterative Upgrade of Green Energy-Saving and Low-Carbon Technologies

Against the backdrop of dual carbon goals, energy conservation and environmental protection have become core development directions for fermentation equipment. Conventional fermentation equipment suffers from low heat exchange efficiency and high consumption of water, electricity and gas, resulting in severe resource waste. Future equipment will optimize heat exchange structures, adopt high-efficiency energy-saving heat exchange assemblies and upgrade waste heat recovery systems to recycle waste heat generated during fermentation and reduce energy consumption of temperature control systems. In addition, the power structure of equipment will be optimized with low-noise, high-efficiency variable-frequency stirring systems that dynamically adjust power according to fermentation conditions to cut power consumption. In material selection, high-corrosion-resistance and long-life food-grade stainless steel composite materials will be used to enhance corrosion and aging resistance of equipment, extend service life, reduce equipment replacement costs and consumable losses, and achieve low-carbon production and cost-efficient maintenance.

(IV) Modular Flexible Production for Diverse Application Scenarios

At present, raw pulp product categories keep expanding with growing demands for niche, customized and multi-batch production. Traditional fixed fermentation equipment delivers a single production mode with poor adaptability. Future raw pulp fermentation equipment will adopt modular and flexible design. Tank volume, stirring system, temperature control module and dissolved oxygen module can be flexibly combined and quickly switched according to production requirements to adapt to fermentation processes of different raw pulp varieties. The modular structure not only meets multi-variety, small-batch and customized production requirements, but also facilitates equipment disassembly, cleaning, maintenance and capacity expansion, greatly lifting equipment utilization rate, lowering investment in production line transformation for enterprises and adapting to diversified development trends of the industry.

(V) Implementation of Full-Process Digital Traceability System

Food safety supervision becomes increasingly stringent, making full-product traceability an industrial necessity. Future raw pulp fermentation equipment will deeply integrate digital traceability technologies to build a full-chain data traceability system covering equipment maintenance, process parameters, production process and finished product delivery. The equipment automatically records operating parameters, maintenance records, cleaning and sterilization data and fault alarm information of each batch; all data are uploaded to the cloud in real time for tamper-proof storage. It facilitates production control, quality traceability and equipment maintenance optimization for manufacturers, meets industrial regulatory requirements, and realizes standardized, transparent and controllable raw pulp fermentation production.

IV. Conclusion

Standard and scientific maintenance of raw pulp fermentation equipment serves as the fundamental guarantee for product quality assurance, stable production conditions and extended equipment service life, while technological iteration and upgrading act as the core driving force to promote high-quality development of the raw pulp fermentation industry. Amid the trend of industrial standardization, intellectualization and greenization, manufacturers shall abandon extensive operation and maintenance modes, establish graded, preventive and standardized equipment maintenance systems to precisely avoid operational risks. Meanwhile, following technological development trends of equipment, enterprises shall gradually realize intelligent and energy-saving upgrading of old equipment. Supported by new equipment systems featuring precise control, aseptic assurance and digital management, manufacturers can continuously improve the stability, safety and economy of raw pulp fermentation production, pushing the industry toward refined, high-end and sustainable development.

Jinzong Enterprise has been focusing on the design and manufacturing of chemical, food, and pharmaceutical machinery and equipment, the development of intelligent control systems, and engineering design and installation for over 20 years. The company has a design and marketing service center in Guangzhou and operates two production factories in the Zhaoqing National High-tech Zone. Jinzong holds the qualification for manufacturing special equipment pressure vessels and the pressure piping installation qualification (GC2). It is a National High-tech Enterprise and a Provincial Specialized and Sophisticated “Little Giant” Enterprise. The company has established a Provincial Engineering Technology Research Center and owns two Guangdong Provincial Famous Brand Products, as well as dozens of product patents, software copyrights, and provincial high-tech products. Jinzong has passed the National Intellectual Property Management Standardization Certification, ISO9001:2015 International Quality System Certification, and EU CE Certification. For many consecutive years, it has been rated as a “Guangdong Province Contract-abiding and Promise-keeping Enterprise” by the Guangdong Provincial Administration for Industry and Commerce. Its customers are spread across more than 50 countries and regions worldwide, and it has gained recognition and support from over 2,000 enterprises both domestically and internationally. As the saying goes, “A craftsman must sharpen his tools to do a good job.” Jinzong Enterprise, adhering to the philosophy of “Quality as Gold, Craftsmanship as Our Core,” provides advanced and automated production lines to manufacturing factories. Domestic and overseas friends are warmly welcome to visit and guide us!