Sandwich activated carbon filter media is an innovative composite filter material that tightly combines activated carbon and supporting materials through a multi-layer structure design, taking into account both efficient adsorption and mechanical stability. Its core adopts a “sandwich” layering process (such as non-woven fabric/activated carbon layer/non-woven fabric), which is widely used in air purification, water treatment and industrial waste gas treatment. It is optimized for intercepting particulate matter and adsorbing chemical pollutants at the same time, realizing the integrated removal of multiple pollutants.
Core structure and function
Multi-layer composite design
Surface protection: two layers of high-permeability non-woven fabric or synthetic fiber mesh on the upper and lower layers intercept large particles of dust, hair and other impurities to prevent clogging of the activated carbon layer.
Core adsorption layer: high specific surface area activated carbon (granules, powder or impregnated carbon fiber) is sandwiched in the middle to capture VOCs, odors and harmful gases (such as formaldehyde, benzene, hydrogen sulfide) through physical adsorption and chemical bonding mechanisms.
Optional functional layer: some models add antibacterial coating or electrostatic electret layer to enhance microbial inhibition or particle adsorption capabilities.
Efficient adsorption and filtration synergy
The specific surface area of the activated carbon layer is 800-1500㎡/g, which can adsorb 0.3-10μm particles and molecular-level gas pollutants, and the comprehensive filtration efficiency meets the MERV 10-14 or EN 1822 standards.
The sandwich structure prevents the escape of activated carbon particles, ensures uniform airflow, and reduces the risk of local penetration.
High strength and durability
The surface material (such as melt-blown polypropylene) provides tear resistance, withstands high wind speed (>2m/s) and humidity fluctuations, and is suitable for dynamic working conditions such as car air conditioners and industrial blowers.
The activated carbon layer is cured to avoid moisture and hardening or channeling effects caused by airflow impact.
Core advantages
Multifunctional integration: Single-stage filter material simultaneously achieves particle interception and gas purification, simplifies system design, and reduces equipment space requirements.
Low pressure drop and energy saving: The open fiber structure maintains airflow resistance below 150Pa, reducing fan energy consumption.
Long life and easy maintenance: Surface pre-filtration extends the activated carbon saturation cycle, and the replacement frequency is 30%-50% lower than that of traditional activated carbon filters.
Environmentally friendly and safe: Food-grade adhesives and heavy metal-free activated carbon ensure harmlessness to the human body, and some models support high-temperature regeneration or harmless incineration.
Typical application scenarios
Home and commercial air purification: composite filter core material, remove PM2.5, formaldehyde and pet odor.
Automotive air conditioning system: Improve the air quality in the car, adsorb exhaust gas (NOx), air conditioning odor and pollen.
Industrial waste gas treatment: VOCs pre-filtration in spray workshops and printing plants to reduce the load on back-end processing equipment.
Drinking water purification: The front carbon layer adsorbs residual chlorine and organic pollutants to protect the life of the reverse osmosis membrane.
Medical and laboratory: Adsorption control of sterilizing gases (such as ozone) in the air circulation of the operating room.
Selection and maintenance guide
Applicable pollutant types:
Chemical gas: Select activated carbon with high iodine value (>1000mg/g), or impregnation type (such as phosphoric acid treatment) to enhance formaldehyde adsorption.
Mixed particle pollution: Increase the surface fiber density (such as gram weight 80-150g/㎡) to improve particle interception efficiency.
System parameter matching:
Select the medium thickness (usually 5-20mm) and activated carbon content (200-800g/㎡) according to the air volume (m³/h), and balance the pressure drop and adsorption capacity.
High humidity environment requires hydrophobic non-woven fabric layer and moisture-proof activated carbon to avoid performance degradation.
Maintenance strategy:
Determine the replacement cycle (usually 6-24 months) through pressure difference monitoring or gas concentration detection. It is recommended to replace every 3-6 months in high pollution scenarios.
Non-cleanable design, need to be replaced regularly; some industrial-grade models support modular disassembly and regeneration.
With structural innovation and performance synergy as its core breakthroughs, sandwich activated carbon filter media has become an efficient solution for multiple pollution scenarios, helping to achieve deep purification of air and water and promoting the achievement of multi-dimensional goals of environmental protection, health and energy efficiency.
