DUCON DFY 500 is an innovative filter engineered specifically for RAM (stenter) machines, using deep-bed microfiber media for sub-micron aerosol control. It delivers high efficiency in the 0.1–3 µm range, features low initial ΔP, and offers a long service life. With DUCON’s patented design, it stands out from competitors. Although optimized for RAM machines, it is successfully applied across many processes listed below.
Efficiency: 95–99.95% (0.1–3 µm)
Initial ΔP: 150–700 Pa
Typical outlet: < 5–20 mg/Nm³
System elements are validated for maximum performance through shop and field testing. With proper cooling and face velocity, stack opacity drops to 5% or below; near-zero opacity is targeted in most processes. The test methodology is defined during design and verified on site with conditioning and acceptance criteria.
As the gas stream passes through the fiber bed, multiple capture mechanisms act simultaneously. After coalescence (merging), enlarged droplets drain. To extend the life of the final filter, the system includes a pre-filter and a high-pressure Venturi scrubber to cool hot gases. The pre-Venturi scrubber provides effective pre-separation of particulates and gas cooling.
PLC-based automation; the exhaust fan automatically adjusts its speed in relation to system vacuum to maintain the internal vacuum–pressure balance without disturbing the connected machines.
Continuous monitoring of inlet gas and wash liquid pH, temperature, level, and filter differential pressure (ΔP).
All controls are displayed on a digital HMI and logged for records.
Inertial Impaction: ≈ 4 µm and larger particles impact fibers due to inertia and are captured.
Interception: 1–3 µm particles follow streamlines and are intercepted on fiber surfaces.
Brownian Diffusion: Sub-micron (< 1 µm) particles reach fibers via random motion; coalesced droplets then drain.
Cyclonic Washer: Lowers exhaust temperature via adiabatic cooling (water evaporation); return water is distributed onto a cyclonic tray to help wash out solids.
Ambient-Air Dilution Cooling: Dilution with ambient air; regulated by a damper or temperature controller.
Air-to-Air Heat Exchangers: Counter-flow heat exchange between clean air and hot process exhaust, with proper condensate control.
Textile RAM (Stenter) Machines
Asphalt Processing
Saturation Processes
Vinyl Coaters / Battery Cases
Deep-Fat Frying
RTO Pre-Filter
Coffee Roasting
Coating Lines
Acid Mist Control
Tank Venting
Chemical Processing
Fertilizer Production
Metalworking (Oil Mist)
Textile Processing
Incineration/Combustion Emissions