2.1.1. Biological Trickling Filter

2.1.1. Biological Trickling Filter

Supported by the Danish Trade and Industry Department, EXPO-NET Danmark A/S has developed an effective biological filter medium called BIO-BLOK®.

Biological trickling filters show a great stability towards fluctuating supply of organic matters. Furthermore, the trickling filter is extremely resistant to occasional occurrences of toxins in the waste water.

In the light of this, the trickling filter is therefore with great advantage being used as highly loaded primary treatment plant. Moreover, the trickling filter is the cheapest method for decomposing of organic matters in the waste water.

By using BIO-BLOK® for trickling filters, the limits of hydraulic surface loads and organic loads have been moved because this modern filter medium does not have the same disadvantages as the old-fashioned stone filters do. Furthermore, height of the filter medium can be reduced resulting in a considerable cutback in operating costs.

EXPO-NET's BIO-BLOK® is:

  • A recently developed special product.
  • Made from the imperishable and environmentally compatible material - polyethylene.
  • Produced with a special surface structure that ensures a quicker development of the biological treatment ability.
  • Constructed as self-supporting modules.
  • Self-cleaning with a big area of flow.
  • Easy to handle.
  • Easy to adjust to both existing and new plants.

Technical specifications of BIO-BLOK®

Type of filter media

BIO-BLOK® 100

BIO-BLOK® 150

BIO-BLOK® 200

BIO-BLOK® 300

Specific surface (m2/m3) (approx.)

100

150

200

300

Area of flow (approx.)

70%

64%

60%

50%

Percentage of hollow space (approx.)

90%

88%

82%

65%

Tube diameter

70mm

55mm

55mm

30mm

Standard module form

54x54x55cm

55x55x55xcm

55x55x55cm

55x25x55cm


The surface measurements have been calculated by the producer. Alterations in process, material and structure may slightly change the figures above (by up to 10%)). Above filter media are available with densities of approx. 0.5 and 0.95.

BIO-BLOK® 100, BIO-BLOK® 150 and BIO-BLOK® 200 are available in heights (lengths of block tubes) from 45cm to 75cm.