Last chance filter
Maintenance-free oil filter mat for seepage troughs and lawn grids
Maintenance-free oil filter mat for seepage troughs and lawn grids
Aktofix is a 3-layer filter mat for filtering and breaking down hydrocarbons. It has been successfully used for over 25 years for stormwater treatment, e.g. in seepage troughs or underneath grass pavers.
The large-area composite mat consists of 2 geotextile outer layers, which fix an activated carbon layer inserted in between. The oil-contaminated water is deposited on the textile threads as it flows through the composite mat, but the oil is also retained on the surface and in the pores of the activated carbon.
The activated carbon is highly porous, 1 gram has a surface area of about 1,000 m². Hydrocarbons are very quickly separated from the water by the activated carbon, stored and much more strongly fixed than on the surface of the textile threads. Thus, the stored oil is not washed out even during very heavy rain events. In addition, due to the stable sponge structure (in contrast to pure textiles), it cannot be compressed due to stress, e.g. from cars, and thus the oil is squeezed out.
The bound oil is biodegraded by microorganisms in the long term. The 3D thread structure of the textiles also distributes and stores air and moisture, and the pore structure of the activated carbon provides ideal living conditions for the oil-degrading microorganisms.
The Aktofix Aquatextil is installed e.g. as a last chance filter under an approx. 30 cm humus layer at seepage troughs or at permeable parking areas under the bedding layer. Due to the very high oil binding capacity and the long-term biological oil degradation, the system is very durable and maintenance-free.
There are 2 standard versions, technical data: Activated carbon insert: approx. 1.2 or 2.5 kg/m², total weight: approx. 1.6 or 3.0 kg/m², thickness: approx. 8 or 13 mm, water permeability kf: approx. 3 x 10-3 m/s, mat width: up to 5.0 m, length: up to 40 m, oil storage capacity: > 3 l/m².
In principle, the Aquatextil is used everywhere under or next to traffic areas where rainwater contaminated by hydrocarbons is to be infiltrated, e.g. in seepage troughs, lawn gravel, etc: Soakaways, grass pavers, grassed parking lots, water-bound surfaces, open paved areas, drain asphalt, drain concrete, water protection zones, open commercial areas, sponge city, sidewalks and bike paths, …