Vacuum Sterilizing Filter

Vacuum Sterilizing Filter

【1】Supplied by Hangzhou Jiejie Mechanical & Electrical Equipment Co., Ltd.; The sterilizing filter primarily utilizes a microfiltration filter element with a large specific surface area and a filtration precision of 0.22μm or higher. It is mainly used to prevent impurities, harmful bacteria, microorganisms, etc., in the air from entering tanks, production lines, cleanrooms, etc., thereby avoiding changes in water quality, product quality, and cleanroom environment. It meets the process requirements of industries such as food, biochemicals, beverages, beer, pharmaceuticals, and electronics.

Filter Element Materials

The main filter materials commonly used for filters include the following:

Mixed Cellulose Ester

Often used to make round single-piece flat filter membranes for fine filtration of liquids and gases;

Polypropylene

Made into pleated form, commonly used in cartridge filters, with larger pore sizes. It is hydrophilic and belongs to coarse filtration materials;

Polyvinylidene Fluoride

A fine filtration material with good heat and chemical stability, as well as steam sterilization resistance. It can be made into hydrophilic filter membranes and is widely used in the pharmaceutical industry for filtering water for sterile preparations and injection water;

Polyethersulfone

Made into pleated form, commonly used in cartridge filters. It has good temperature and hydrolysis resistance, is hydrophilic, and is used for fine filtration of solutions requiring higher precision;

Nylon

Made into pleated form, commonly used in cartridge filters. It is hydrophilic and often used for fine filtration of liquids;

Polytetrafluoroethylene

Made into pleated form, commonly used in cartridge filters. It is a hydrophobic material and is widely used. It has good heat and chemical stability and is often used for fine filtration of water, inorganic solvents, and air.

Additionally, filter materials can be divided into two types based on their relationship with water: hydrophilic (water-wettable) and hydrophobic (water-repellent).

Hydrophilic filter materials are mainly used for filtration and sterilization of water or water/organic solvent mixtures. Hydrophobic filter materials are used by intercepting or "guiding" water into the filter membrane, primarily for filtration of solvents, acids, alkalis, and chemicals, as well as for tank/equipment, process gas, and fermentation inlet/outlet gas filtration.

Vacuum Sterilizing FilterFeatures

（1）Sterilizing filters are generally designed with a cross-suspended structure and horizontal inlet/outlet. Multi-cartridge filters can be designed as floor-standing models.

（2）Depending on the application, they can be divided into pre-filters and fine filters based on actual needs.

（3）Airflow direction: from the outside to the inside through the filter element.

（4）Compressed air entering the sterilizing filter must first pass through at least three stages of precision filters and a dryer. It must remove oil, water, and dust, with an oil mist concentration of ≤0.01 PPM. Otherwise, the lifespan of the sterilizing filter element will be affected, and the expected sterilization effect will not be achieved.

（5）Regular sterilization should be performed weekly or monthly, 1-2 times depending on actual usage, each time for 30 minutes. Use clean saturated steam with a filtration precision of 1μm for sterilization. Steam temperature <140°C, steam pressure <0.3 MPa. Valves should be opened and closed slowly.

（6）When used for tanks or equipment, its main function is to connect to the atmosphere to prevent negative pressure inside the equipment and isolate airborne contaminants. Its filtration function is limited, so there are minimal requirements for filtration.

Integrity Testing

To ensure the filtration effectiveness of the sterilizing filter, integrity testing must be conducted before and after use to confirm its efficiency. The main integrity testing methods include forward flow, bubble point, and water intrusion tests. The mainstream testers include Pall's Flowstar and Millipore's Integritest.

With the deepening implementation of the 98th edition of GMP and the new drug GMP certification inspection and evaluation standards, integrity testing of filters has gained increasing attention from enterprises and drug regulatory inspectors. It is almost always inspected during audits, especially for filters used in critical processes and control steps, which have become a focal point in various types of inspections.

Among the filter materials mentioned above, mixed cellulose ester and polypropylene (PP) are difficult to test for integrity and are generally considered untestable. Therefore, they cannot serve as reliable terminal sterilizing filters and pose significant sterile quality risks.

Conventional Technical Parameters

Working pressure: 0.6–0.8 MPa;

Inlet temperature: 0–80°C; 0–121°C (steam);

Filtration precision: 0.22μm or higher, falling under the category of microfiltration;

Applicable media: Used for gas and liquid filtration.

Our company's domestic brand filter elements are self-manufactured replacement filter elements, using filter materials imported from Germany's HV Company. The registered trademark is "Jiejie." Other brands mentioned by our company hold no brand significance and are only for model reference and usage guidance.