Conversion of Filter Bag House to Pleated Cartridge Filter Elements

bag house filter to cartridge filter upgradeFor example; Converting a Mikropul bag house to a cartridge filter system provided advantages, detailed below:

  • An increase in filter media area, was obtained, from 210m2 to 676m2, this enabled the air flow to be virtually doubled (in theory and dependant on fan capacity available), taking into account the media permeability and recommended filter velocities. (Other limiting factors will also need to be considered, in the event of actually increasing the airflow to >38,000 m3/hr).
  • With the current (filter bag) air flow, the filter Differential Pressure (DP), and filter velocity, for cartridge filters, will be substantially less (than design), ensuring the filters will last many years. Expected life between 5 – 10 years.
  • Extract/stack emissions will be substantially reduced; guarantee of emissions less than 2mg/m3, total particulate (emissions are currently well above this), providing:
    • R&B Industrial convert and install new cartridge filters.
    • There are no faults/leaks/fatigue in cell plate, or existing venturies.

The header tank also requires replacement, as the existing tank and valve size are too small to be able to effectively clean the cartridge filters with increased filter area. This will also require new pulse jet tubes.

Present media area – 2.3m x 0.38m x 264 = 210m2.
Proposed media area – 2.56m2 x 264 = 676m2.

Overall Benefits:-

  1. Increased media area.
  2. Reduced filter velocity.
  3. Decreased filter pressure drop.
  4. Increased system performance – extra pressure / flow available.
  5. Increased filter life.
  6. Reduced emissions. (Predicted below 2mg / m3 total particulate)

Pre-coat Powder is used in Dust Extraction Systems in the following Application/Conditions:

  1. Where very fine dust is present in the product, especially when cyclones/drop out/ baffle boxes etc are used as pre-filters.
  2. The pre-coat powder is inserted into the extraction system (i.e. LEV Hoods or in ducting) when new filters are installed but before product reaches the clean filters.

The pre-coat powder forms a surface coating on the filters which provides the following benefits:

  • Prevents very fine dust blinding new filters.
  • The filters work more efficiently when pre-coat powder is applied.
  • The pre-coat powder will reduce extraction emissions, with new filters, which would otherwise increase while a surface coating of product builds up.

Note pre-coat powder can also help to absorb oil mists/ neutralise acidic dusts.

Filter Installation; 264 cartridge filters  into mikropul extractor, Including:

  • Written Method statement
  • Removal and bagging of existing filters, checking venturies, converting to cartridge filter sealing system
  • Fitting new cartridge filters, checking flange and door seals and replacing where necessary.
  • Application of Pre-coat powder if applicable.
  • Checking Diaphragm, Solenoid Valve and adjusting timings, to improve cleaning, as necessary.
  • Setting up of automaic fan disharge damper (if ordered – see Q2280)
  • A check of compressed air quality; i.e. oil/water content (if accessible)
  • Recording of filter DP and System air flow/static pressure after completion of work.

Completion of filter unit service report

Remove existing header tank:
We have allocated 2 man days to carry out this work

  • Remove existing pulse tubes
  • Grind off, existing welded bulkhead connectors
  • Drill new holes for larger 1 ½” bulkhead connectors (requires Doeflex assistance)

Note: quote is based on assumption of utilising the existing pilot valve and sequence controllers.

Manufacture, Supply And Install;

  • 2 off header tanks , fitted with 1 ½” diaphragm valves; see drawings 3.4m + 3.2m L
  • Note header tanks will be fitted in series.
  • 33 off 1 ½” new pulse jet tubes, 1.8m L, supplied with nozzles, and 12mm diam holes

33 off 1 ½” bulkhead connectors