leftBar
BHS Filtration
navigation:

Candle Filter

General Description

Criteria Download PDF Brochure PDF

BHS-Candle Filters work intermittently using filter elements arranged vertically in a pressure vessel.

BHS-Candle Filters are used as deep-bed or precoat filters for clarifying liquids with a low solids content. Although the BHS-Candle Filter is used ideally for batch filtration it can also be employed for continuous cycles.

The suspension is filled into the pressure vessel and constantly topped up by pump. The filter cake builds on the outside of the filter candles, the filtrate being discharged from the inside of the candle through immersed and battery pipes. The filter cake can be dried after filtration. A blast of compressed air finally lifts and discharges the cake.

Technical Description

The filter elements (candles) are covered with replaceable filter cloths and suspended from the top end of the filter. During filtration, the filter cloths press against the waffle-type struc-ture of the supporting tube, thus ensuring good filter cake adhesion during the filtration phase. Inside the candles, the filtrate is delivered through risers to the discharge batteries.

Under the aspect of optimisation, the filter candles are arranged in close proximity within the pressure vessel. The candles are mounted on individual collection batteries. The filter cake can be shed battery by battery or discharged in portions.

 

Heel filtration

Operating safety also includes a process for filtering small quantities of liquid and vessel heel filtration.

Two alternatives are available for this purpose:

  • BHS falling film filtration
  • Internally filtering candles at the vessel neck

Both alternatives afford complete heel filtration with a minimum of compressed
gas.

Cake discharge

At the end of filtration, the filtered solid matter is discharged completely and safely. During filtration, the cloth is pressed against the surface of the supporting tube. For cleaning, a pulse of compressed gas or liquid from behind restores the cloth to its original shape, lifting and repelling the built-up filter cake.

Back to top

Applications

Fine chemistry:
 
  • Highly corrosive and aggressive media
  • Catalysts after hydration
  • Bleaching earth removal
  • Recovery of activated carbon
Pharmacy:
 
  • Clarification of antibiotic solutions
  • Solvent filtration at high temperatures
  • Activated carbon and catalyst removal

Industrial effluent:
 
  • Polymer particles from waste water
  • Heavy metal hydroxides
  • Ceramic and glass residue from circulating water
    Kreislaufwasser

Applications

  • Operating pressure up to 10 bar
  • Operating temperatures up to 250°C
  • Cake thickness up to 20 mm
  • Intermittent operation
  • Filtration rates ranging from 30 to 5000 l/m2h
  • Solid contents up to 3 %
  • Main grain size distribution of 1 to 50 µm
    (in some instances up to several hundred µm)
 Environmental technology:

 
  • Flue dusts from wet scrubbers
  • Biological residues with filtration aids
  • Residues from cooling circuits

 
Clarifying filtration:
 
  • Removal of impurities by adding filtration aids von Filterhilfsmitteln
  • Secondary clarification of centrifugal overflow, centrifugates and filtrates

 

 

Back to top

Technical Data

  type
number
of
elements
  		Filter-
area
 
in m2 		X
Aktive length
of candles
in mm 		A
Vessel
diameter
in mm 		B
Vessel
hight
in mm 		Filling
volume*
 
  		Filter-
weight
empty
kg
   K 7 - 2 7   2.38 1200 500 2100 240 250
   K 7 - 4   3.56 1800 2700 330 320
 K 13 - 4 13   4.41 1200 700 2300 450 480
 K 13 - 7   6.62 1800 2900 600 610
 K 19 - 6 19   6.45 1200 700 2300 450 550
   K 19 - 10   9.67 1800 2900 600 710
   K 31 - 11 31 10.52 1200 1000 2700 1070 990
   K 31 - 16 15.78 1800 3300 1410 1250
   K 37 - 13 37 12.55 1200 1000 2700 1020 1040
   K 37 - 19 18.83 1800 3300 1240 1330
   K 49 - 17 49 16.63 1200 1200 2900 1580 1560
   K 49 - 25 24.94 1800 3500 2060 1950
   K 61 - 21 61 20.70 1200 1300 3000 1860 1880
   K 61 - 31 31.05 1800 3600 2410 2340
   K 69 - 23 69 23.41 1200 1400 3000 2210 2190
   K 69 - 35 35.12 1800 3600 2850 2730
   K 77 - 26 77 26.13 1200 1500 3100 2620 2670
   K 77 - 39 39.19 1800 3700 3370 3270
   K 91 - 31 91 30.88 1200 1600 3200 3010 2990
   K 91 - 46 46.31 1800 3200 3010 2990

*Venting at cylinder at battery level

Materials

  • Metallic materials contacting the product:
    1.4541, 1.4571, 1.4539, Hastelloy, Steel enamelled
  • Seals:
    PE, PA, PVDF, PTFE, aramid, EPDM, butyl rubber
  • Filter fabrics:
    Textile: PA, Polyester, PTFE
    Metals: 1.4571, 1.4539, Hastelloy
    Base frame: standard coated steel, special steel

Technical data may change due to technical progress. Subject to modification without notice.

Back to Top

Related Articles

Back to top