Trickling filter technology

The trickling filter technology is one of the oldest technologies for biological wastewater treatment and has undergone some significant developments since it’s early days. Nowadays it’s considered an easy-to-operate and almost maintenance-free technology with low power demand. The only power requirement goes for pumping, there is no need for power-hungry blowers, since the aeration is provided by natural draft.
The core of a trickling filter is a fixed bed biological reactor that operates under mostly aerobic conditions. Pre-settled wastewater is continuously and evenly distributed on top of the filter-media.
Organic and biodegradable inorganic wastewater components are degraded by a biofilm covering the surface of the media.
Thus, the key component of a modern trickling filter is the structured media packing that provides a large surface for biofilm and sufficient ventilation while the water migrates through the filter.

HEWITECH trickling filter media can be used in any trickling filter, from high loaded roughing filters to predominantly nitrifying filters.

HEWiTECH trickling filters are used wordwide and contribute to the protection of water resources and the environment

Trickling filter media needs to be placed on a proper base.
The support structure needs to meet structural requirements and must be suitable to fulfill process requirement with regard to air supply and blockage prevention.
The support structure HEWiPIER fulfills the requirements addressed to support structure:

  • It can be adapted to any design weight. Typical design weights range from 1000 kg/m2 of floor area for shallow load loaded filters up to 8000 kg/m2 of floor area for tall high loaded filters.
  • It stanchion parts have an integrated slope compensation, hence the piers are installed vertically on a sloped floor (compensation up to 8% or 4.5 Deg)
  • The piers consists of long-lasting PVC pipes with base and head plates. The support grating is made of rigid fiberglass beams with > 50% glass content
  • HEWiTECH provides the structural design and installation instructions and installation drawings
  • all components are easy and fast to install and the pieces fit together.

Trickling filter FAQ


  • Trickle grids NC
  • Trickle grids VC
  • Cellular fills CF
  • Crossflow components
  • Drift eliminators
  • Cooling tower sprayer

Rain water

  • VARIO Box Series
  • CONTROL Box Series
  • Drainage Components
  • Sport Base
  • TREE-Boxes
  • Filter Cassettes


  • Dust extraction
  • Exhaust air purification
  • Curtain components
  • Trickle fill series