Progressive treatment
The progressive treatment decanter has been specially studied and designed for the treatment of run-off water from surfaces where the pollutant load is potentially high and continuous. This includes car wreck storage areas, materials sorting and storage centres, technical surfaces and industrial sites.
Dimensions
The size of a DTP or DPTV type progressive treatment clarifier depends on local rainfall and geographical area.
Progressive treatment decanters are therefore suitable for treating flows <= Q1year with an optimum hydraulic head varying from 0 to 2m/h. Exceptional flows (5% of cumulative rainfall) are treated less thoroughly, but significantly, with a hydraulic load of 2 to 4.5 m/h.
The graph below shows the rainfall analyses used to design the range.
The operating principle
Containment of floating matter in the 1st compartment (screening on intermediate partition)
Optimised hydraulic operation for particle settling:
- An overflow channel ensuring uniform hydraulic distribution throughout the filter
- A sludge storage silo, isolated from the circulation flow, prevents the release of settled sludge.
Automatic shut-off in the event of major spillage of light liquids (hydrocarbons).
Gravity operation (no energy input)
No consumables to replace periodically Optimum tube bundle diameter, enabling a balance between spaced maintenance and a measured unit size.