Cartridge Type Filters

The choice of cartridge filter depends on the application.

  • Cartridge filters are preferable for systems with particles are finer.
  • Cartridge filters can be surface or depth type filters:
    • Surface filters are best if you are filtering sediment of similar-sized particles. If all particles are e.g. five microns, a pleated 5-micron filter works best because it has more surface area than other filters
    • Depth-type filters capture particles and contaminants through the total thickness of the medium. Compared with pleated surface filters, depth filters have a limited surface area, but they have the advantage of depth.
  • It can be generally stated that if the size of filter surface is increased, higher flows are possible, the filter lasts longer, and the dirt holding capacity increases.
  • Cartridge filters are normally designed disposable: this means that they have to be replaced when the filter is totally damaged. Compared to a conventional bag filter that offers a maximum of 99% efficiency for particle range to 7 microns, cartridge filter systems can filter up to 99.97% to 1 micron. (Today, we also have cartridges which can filter to 0.3 microns).

Special Features

  • Compact equipment, requiring small footprint and minimal foundation
  • Very low outlet emission level (less than 5mg/M3) makes these suitable for indoor installation
  • Available in capacities from 1,500 Am3/h to 30,000 Am3/h

Cartridge elements in a cartridge filter system are built out of fine filter media arranged in a pleated manner, due to which a very large filter area is accommodated in a very small cylindrical shape. The net effect is that a cartridge filter system occupies much smaller area and space compared to a conventional bag filter system (one-eighth).

The architecture of the cartridge filter system is designed in such a way that servicing or replacement of filters takes just a few minutes and can be carried out by one person, unlike a conventional bag filter system which requires up to several days to open and replace filters.

The dust dislodged by the reverse pulse jet cleaning system is pushed down. This obviates re-entrainment of the dust into the filters. The filters are continuously cleaned with reverse air blasts controlled by an electronic sequential controller. The filter system remains continuously operative at its peak efficiency.

In summary cartridge filter systems offer greater filtration efficiency at a reduced cost and therefore, are a better choice where the dust has to be completely removed or recovered. In many filtering applications, a choice between the use of a cartridge filter and a bag filter has to be made.

DISA Cartridge Filters for Fettling and
Grinding Operations

Fettling is a process to trim or clean the rough edges of metal castings. The operation involves the removal of unwanted metal fines such as flashings and risers by grinding and cutting.

The Challenge

  • Very fine metal dust is generated
  • The dust is known to be carcinogenic
  • Ferrous dust is corrosive to structures and painted surfaces
  • Risk of fire due to sparks     
  • Metal dust causes damage to moving parts
  • Abrasive dust is created by worn out grinding media

The Solution

  • Effective suction from the source of generation
  • Correct use of filter media
  • Adequate spark diffusing mechanism
  • Right conveying velocity of dusty air (heavy dust)
  • Continuous discharge of dust to avoid fire hazard
  • Explosion vent and CO2 dosing depending on casting material



Cartridge Filter Features

  • Emissions are guaranteed at <5 mg/Nm3 (< 2mg/Nm3 can be achieved with an additional secondary filter)
  • Chimney not required – cost saving
  • ID fan mounted on top of filter
  • Compact design and small footprint area     
  • Special cartridge design to handle fine metal dust.
  • Efficient automatic cleaning mechanism
  • High energy savings by automatic damper control
  • VFD controlled fan to save energy
  • Inbuilt spark arrestor to ensure safety
  • Easy dust removal and handling
  • Factory tested, easy to install – plug and play
  • No special foundation required