In pharmaceutical production, aseptic environments are core requirements to ensure drug quality and patient safety. Compressed air, as an indispensable power source and process gas in production, its cleanliness directly affects the sterility of pharmaceuticals. As a common compressed air treatment device, can a refrigeration air dryer effectively guarantee aseptic conditions in pharmaceutical production? This article analyzes from technical principles, industry standards, practical applications, and other perspectives, combined with the product practices of Hangzhou Risheng Decontamination Equipment Co., Ltd., to explore the key role of refrigeration air dryers in aseptic pharmaceutical production.
Core Challenges of Aseptic Pharmaceutical Production
Aseptic conditions in pharmaceutical production have extremely high requirements. Any microbial contamination or particulate impurities may lead to drug failure or even safety accidents. According to the 2025 edition of the Chinese Pharmacopoeia and GB/T 19973.2-2025 national standards, aseptic production must meet the following key requirements:
Air Cleanliness: The production environment must reach ISO 5 (Class 100) or higher standards, with strict control of microbial suspended particles.
Compressed Air Quality: Compressed air must comply with ISO 8573-1:2010 standards, with dew point temperature, oil content, particulate impurities, and other indicators meeting process requirements.
Risk Control: Media simulation tests, dynamic environmental monitoring, and other means must be used to ensure the reliability of aseptic operations.
Core Challenges:
Humidity Control: Moist air provides a breeding ground for microorganisms, and condensed water may contaminate drugs or equipment.
Cross-Contamination: If the compressed air pipeline system is not thoroughly dried, it may become a carrier for microbial spread.
Compliance Verification: Regular performance qualification (PQ) and operational qualification (OQ) of drying equipment are required to ensure compliance with international standards such as GMP and FDA.
Working Principles and Technical Advantages of Refrigeration Air Dryers
Working Principles
Refrigeration air dryers (cold dryers) cool compressed air below the dew point temperature through a refrigeration system, condensing water vapor into liquid water, which is then discharged through a water-air separator. Core components include:
Heat Exchanger: Pre-cools the incoming air, recovers cold energy, and reduces energy consumption.
Evaporator: Cools the air to 2-10°C, precipitating moisture.
Water-Air Separator: Efficiently separates liquid water to avoid secondary contamination.
Drainage System: Automatically discharges condensed water to prevent microbial growth.
Technical Advantages
Efficient Dehumidification: Stable dew point temperature control at 3-10°C, meeting most pharmaceutical process requirements.
No Consumable Consumption: Eliminates the need to replace adsorbents, reducing maintenance costs and operational complexity.
Low-Energy Design: Uses frequency conversion technology and high-efficiency refrigeration systems, consuming 30%-50% less energy than traditional adsorption dryers.
Modular Integration: Can be combined with multi-stage filters and sterile-grade filter elements to form a complete aseptic air treatment solution.
Comparison with Adsorption Dryers
| Characteristics | Refrigeration Air Dryer | Adsorption Dryer |
|---|---|---|
| Dew Point Temperature | 3-10°C | -20°C to -70°C |
| Energy Consumption | Low (no thermal regeneration) | High (requires regeneration gas) |
| Maintenance Cost | Low (no consumable replacement) | High (requires regular adsorbent replacement) |
| Application Scenarios | Conventional aseptic production (e.g., solid dosage forms) | High-requirement scenarios (e.g., lyophilization of injectables) |
Conclusion: Refrigeration air dryers can effectively control humidity in conventional pharmaceutical production. Combined with downstream sterile filtration systems, they can meet most aseptic process requirements. For ultra-low dew point requirements (e.g., below -40°C), a combined "refrigeration + adsorption" drying solution is recommended.
Compliance Verification of Refrigeration Air Dryers in the Pharmaceutical Industry
Industry Standards and Certifications
Refrigeration air dryers from Hangzhou Risheng Decontamination Equipment Co., Ltd. have passed the following certifications and tests to ensure compliance with pharmaceutical industry requirements:
ISO 8573-1:2010: Compressed air quality class certification (dew point, oil content, particles).
GMP Certification: Complies with the requirements of China's Good Manufacturing Practice for Drugs for air systems.
FDA Standards: Materials meet FDA 21 CFR Part 177 requirements for food-grade stainless steel and seals.
Microbial Challenge Test: Verified by third-party testing institutions, with post-drying air quality achieving microbial residue ≤ 0.1 CFU/m³.
Key Design Details
Antimicrobial Materials: Evaporators and pipelines use 316L stainless steel with electropolished surfaces to reduce microbial adhesion.
Anti-Condensation Design: Equipment casings and pipelines use thermal insulation materials to avoid secondary condensation caused by external temperature differences.
Online Monitoring: Integrated with dew point sensors and particle counters for real-time air quality monitoring, with traceable data.
Validation Processes
Installation Qualification (IQ): Checks whether equipment installation meets design drawings and GMP requirements.
Operational Qualification (OQ): Tests equipment stability under different working conditions, including dew point fluctuations and energy consumption.
Performance Qualification (PQ): Verifies the sterilization capability of dryers under extreme conditions through media simulation tests.
Practical Cases: Application Scenarios of Risheng Refrigeration Air Dryers
Case 1: Oral Solid Dosage Production Line
A pharmaceutical enterprise uses Risheng RSLF series refrigeration air dryers with a processing capacity of 50 Nm³/min for granulation, tableting, and other processes. Equipment configuration:
Pre-filter: Removes large particles and oil mist.
Cold Dryer: Controls dew point at 5°C to ensure dry compressed air.
Sterile-Grade Filter: Installs 0.01μm filter elements downstream to intercept microorganisms and phages.
Effect: After 12 consecutive months of operation, environmental monitoring shows microbial suspended particles ≤ 1 CFU/m³, meeting ISO 7 cleanliness requirements.
Case 2: Aseptic API Production
In the aseptic API drying process, Risheng's combined drying system (cold dryer + adsorption dryer) controls the dew point at -40°C, while integrating online TOC (total organic carbon) monitoring to ensure no chemical residues in compressed air. This solution has passed FDA on-site audits, with products exported to European and American markets.
Case 3: Fermentation Workshop in Biopharmaceuticals
A biopharmaceutical enterprise uses Risheng's intelligent cold dryers combined with IoT technology for remote monitoring. The equipment automatically adjusts refrigeration power according to fermenter pressure, reducing energy consumption by 18%. Regular CIP (cleaning in place) and SIP (sterilization in place) prevent microbial growth.
Maintenance and Validation: Keys to Ensuring Long-Term Aseptic Performance
Routine Maintenance
Drainage System Inspection: Clean the automatic drain weekly to prevent blockages causing condensed water retention.
Filter Element Replacement: Pre-filters and sterile-grade filter elements are recommended for replacement every 6 months, with specific cycles adjusted based on differential pressure alarms.
Refrigeration System Maintenance: Check refrigerant pressure and compressor operation status annually to ensure stable refrigeration efficiency.
Regular Validation
Dew Point Calibration: Calibrate with a high-precision dew point meter quarterly, with an error ≤ ±0.5°C.
Microbial Detection: Conduct monthly airborne and settle plate microbial tests on post-dried air, with results ≤ 1 CFU/dish.
Integrity Testing: Perform bubble point tests on sterile-grade filter elements annually to ensure filtration efficiency compliance.
Fault Handling
Elevated Dew Point: Possible causes include refrigeration system failures, high inlet temperature, or filter blockages, requiring step-by-step troubleshooting and repair.
Microbial Overstandard: Require comprehensive disinfection of equipment, replacement of filter elements, and traceability of contamination sources.
Frequently Asked Questions (FAQ)
Q1: Can refrigeration air dryers completely replace adsorption dryers?
A: In conventional pharmaceutical production, refrigeration air dryers can meet most process requirements. For ultra-low dew points (e.g., below -40°C), a combined "refrigeration + adsorption" solution is recommended to balance efficiency and cost.
Q2: How to verify the aseptic performance of refrigeration air dryers?
A: Comprehensive evaluation can be conducted through media simulation tests, microbial challenge tests, and online monitoring data. Risheng equipment provides a complete validation document package, including IQ/OQ/PQ reports.
Q3: What is the energy consumption of refrigeration air dryers?
A: Take Risheng RSLF-50 cold dryer as an example. When processing 50 Nm³/min of air, the power is only 5.5kW, saving about 40% energy compared to adsorption dryers.
Q4: Is equipment maintenance complicated?
A: Risheng cold dryers adopt modular design for simple maintenance. Routine maintenance only involves cleaning the drain and replacing filter elements, with professional maintenance required once a year.
Q5: Can it adapt to high-humidity environments?
A: The equipment is designed to adapt to inlet humidity up to 100%RH, ensuring stable dew point through an efficient condensation system.
Conclusion
Refrigeration air dryers effectively control compressed air humidity in pharmaceutical production through efficient dehumidification, low-energy operation, and modular design. Combined with downstream sterile filtration systems, they can meet most aseptic process requirements. Products from Hangzhou Risheng Decontamination Equipment Co., Ltd. provide reliable aseptic air solutions for pharmaceutical enterprises through strict compliance certifications and practical case validation. When selecting drying equipment, comprehensive evaluation should be based on specific process requirements (e.g., dew point temperature, energy consumption budget), with regular maintenance and validation to ensure drug quality and production safety.
About Hangzhou Risheng Decontamination Equipment Co., Ltd.
Hangzhou Risheng Decontamination Equipment Co., Ltd. is a high-tech enterprise focused on the R&D and manufacturing of compressed air purification equipment, offering products including refrigeration air dryers, adsorption dryers, combined drying systems, etc. Adhering to the philosophy of "innovation-driven, quality-first," the company has passed certifications such as ISO 9001 and GMP, providing customized solutions for pharmaceutical, food, electronics, and other industries. For more information, visit: https://www.risheng-airdryer.com/.