Selection of filter velocity of pulsed bag filter

Selection of filter velocity of pulsed bag filter

Selection of filtration speed: Filtration speed is a key factor in the selection of pulsed bag filter, which should be determined according to the properties of dust or dust, application occasions, dust size, viscosity, gas temperature, water content, dust concentration and different filter materials. When the dust particle size is fine, high temperature, humidity, high concentration, large viscosity should be selected low value. Such as 1 m/min or less; On the contrary, high value can be selected, generally not more than 1.5m/min. For dust with large particle size, normal temperature, dry, non-viscous, and very low concentration, 1.5 ~ 2m/min is optional. Filter speed selection, should be calculated in the reduction of a chamber (ash) filter area when the net filter wind speed should not exceed the above values.

2. Filter material [3] : The filter material should be considered according to the temperature, water content, acid and alkali properties, dust viscosity, concentration, grinding and pecking ability and other levels and sizes. Generally, polyester needling felt of 500 ~ 550g/m2 is used at room temperature or ≤130°C according to the dust gas temperature when water content is small and acid-free. At <250°C, aron Nonemex needling felt or 800g/m2 fiberglass needling felt or 800g/m2 weft double fiberglass fabric or Flemus [FMS] high-temperature filter material (fiberglass cannot be used with fluoride gas) is selected. When the water content is larger, and the concentration of dust is larger, it is appropriate to choose, filter material (or anti-condensation filter material) or coated filter material (the base cloth should be treated acupuncture felt). Ryton polyphenylene sulfide (Ryton POLYphenylene sulfide) is often used when the dust gas contains acid and alkaline and the gas temperature is ≤190°C. P84(polyimide) acupuncture felt is used when gas temperature ≤240°C and acid-base resistance is not too high.

When the dust containing gas is inflammable and explosive gas, anti-electrostatic (three-proof) nylon needling felt is selected. 3. Control instrument: The dust removal control of pulsed bag filter adopts PLC microcomputer program control instrument, divided pressure (automatic), timing (automatic), manual three control modes. Constant pressure control: control according to the set pressure difference. When the pressure difference of the dust collector exceeds the set value, each room will be cleaned one by one automatically. Timing control: according to the set time, every other cleaning cycle, each room in turn clean the ash again. Manual control: the on-site operating cabinet can be manually controlled to automatically clean the ash in each room in turn, or separately clean the ash in each room. The control mode is selected by the user. If the user has no requirements, the supply shall be controlled by timing.