Differences Between PTFE Filter Media and Glass Fiber Filter Media
PTFE (polytetrafluoroethylene) filter media and glass fiber filter media are commonly used materials in the industrial filtration field. They differ significantly in terms of material properties, filtration performance, application scenarios, weather resistance, and other aspects. The detailed comparisons are as follows:
1. Essential Material Characteristics
PTFE Filter Media: It is a synthetic polymer material (fluoropolymer) with flexible properties. Its molecular structure contains stable carbon-fluorine bonds, which endow it with unique physical and chemical properties different from traditional polymers.
Glass Fiber Filter Media: It is an inorganic non-metallic material composed of silicate fibers, presenting rigid characteristics. The fibers are formed by melting and drawing silicate raw materials, with a relatively stable inorganic structure.
2. Chemical Stability
PTFE Filter Media: It has extremely strong corrosion resistance. It can resist strong acids, strong alkalis, organic solvents, and strong oxidants, and hardly reacts with any chemical substances. This makes it applicable to various harsh chemical environments where other filter materials are difficult to adapt.
Glass Fiber Filter Media: It has good resistance to strong acids (such as sulfuric acid), but is not resistant to strong alkalis—strong alkalis will corrode the siloxane bonds in the glass fiber structure, leading to damage to the filter media. It has good stability to some organic solvents, but its overall chemical adaptability is narrower than that of PTFE.
3. Temperature Resistance Range
PTFE Filter Media: It has excellent low-temperature and medium-temperature resistance. The continuous operating temperature ranges from -200℃ to 260℃, and it can withstand high temperatures of 300℃ for a short time. It maintains stable performance without brittle fracture at low temperatures and no decomposition at medium temperatures.
Glass Fiber Filter Media: Its high-temperature resistance is far superior to that of PTFE. The continuous operating temperature is between 200℃ and 550℃, and some high-end models can withstand short-term high temperatures above 1000℃. It is the preferred filter material for high-temperature flue gas and high-temperature liquid filtration scenarios.
4. Filtration Precision
PTFE Filter Media: Its pore size is uniform and controllable, generally ranging from 0.1μm to 10μm, which can realize high-precision filtration. The surface of PTFE material is extremely smooth, and particulate matter is not easy to adhere to the surface, thus effectively reducing the risk of filter blockage.
Glass Fiber Filter Media: Its filtration precision is medium, with a pore size range of 1μm to 20μm. The pore distribution of the fiber is relatively uneven due to the influence of the fiber weaving process. The fiber surface is rough, which is easy to adsorb particulate matter, and the filter media is prone to blockage after long-term use.
5. Hydrophobic/Oleophobic Properties
PTFE Filter Media: It has excellent hydrophobic and oleophobic properties due to its extremely low surface tension. This characteristic enables it to effectively separate gas and liquid, and it is not easy to adhere to oil stains and moisture during filtration, which is suitable for the filtration of oil-containing and water-containing media.
Glass Fiber Filter Media: It has strong hydrophilicity and is easy to absorb moisture and polar liquids. It has no oleophobic property, so when processing oil-containing media, oil stains are easy to adhere to the fiber surface, resulting in rapid blockage of the filter media and affecting the filtration efficiency.
6. Mechanical Strength
PTFE Filter Media: It has good flexibility, strong bending resistance and tear resistance, and is not easy to break due to mechanical deformation. However, its tensile strength is relatively low, so it usually needs to be combined with a support skeleton (such as polyester mesh) to enhance its mechanical properties during application.
Glass Fiber Filter Media: It has high rigidity and strong tensile strength, but its brittleness is large and it is easy to break. It is not resistant to bending and vibration, so it is necessary to avoid mechanical impact during installation and use to prevent the filter media from being damaged.
7. Environmental Protection and Reusability
PTFE Filter Media: It is non-degradable, and the disposal of waste filter media is difficult, which may cause certain environmental pressure. However, it can be reused after cleaning (such as ultrasonic cleaning) due to its smooth surface and stable material properties, so it has a long service life.
Glass Fiber Filter Media: It is degradable, and there is no toxic residue after incineration, so it has better environmental protection. However, the fiber is easy to break after cleaning, and the number of repeated uses is limited, so its service life is relatively short.
8. Application Scenarios
PTFE Filter Media: 1. Filtration of corrosive media in chemical and pharmaceutical industries (such as strong acid and strong alkali filtrates); 2. High-precision gas/liquid filtration in food and beverage, electronics industries; 3. Filtration of oil-containing and water-containing gases (such as air compressor exhaust, oil-gas separation).
Glass Fiber Filter Media: 1. High-temperature flue gas filtration (such as boiler exhaust gas, metallurgical furnace flue gas dust removal); 2. Medium-precision liquid filtration in strong acid environment; 3. Primary and medium-efficiency filtration in air purification field (such as central air-conditioning filter screen).
9. Cost
PTFE Filter Media: The price of raw materials is high, and the overall cost is about 2-5 times that of glass fiber filter media, which is a high-cost filter material.
Glass Fiber Filter Media: The price of raw materials is low, the processing cost is also low, and it has high cost performance, which is suitable for large-scale and low-cost filtration needs.
