6367
Prefilters with cleaning process column for filter material in pozzolan Polyester

A decolloid, also called prefilter or clogging indicator, retains suspended matter. Placed after a pit all waters or a settling digester, It avoids premature clogging downstream facilities (spreading, filter beds, ...).

Rapid sizing rules, according to local regulations:
- 5 to 10% of the volume of a pit all waters.
- 10 to 20% of the volume of a digester digester.
PDF Technical sheet
The decolloid is used as a fuse, the suspended solids are trapped there, thus protecting the elements located downstream of the die (sand filter ...). It is operational after filling with pozzolan (independent supply - see sheet 6095).

The horizontal "tee" shaped inlet provides a jet breeze function. The effluent arrives in the upper part of the filtering mass, in order to facilitate the maintenance operations in the event of clogging (this principle limits the actions of withdrawal of the filter material at each inspection and emptying).

All our models of PRV decolloiders are equipped with a technical floor, a unclogging column and a tilting lid allowing maximum accessibility inside the tank.

The decolloid should be filled with pozzolan, a mineral, heavy filter material (regular particle size between 20 and 40 mm).

Reminder: The pozzolan must be ordered separately and it is delivered in bags of 40kg (about 59 liters) reference PZ01.
The appliance will be installed outside the building and installed perfectly level. He will be buried outside a vehicle crossing. Its lid will reach ground level and remain easily accessible for maintenance. The bottom of the excavation will be perfectly flat and covered with 10 cm of sand. The fill will be made with sand or gravel. Apply the water before the backfill.
Annually, aspirate the supernatant.
Perform partial unclogging by backwashing with clean water through the unclogging column.
If clogging persists, check if the all-water pit or the digester settler should not be drained. In average, the filter material is to be changed every 2 years.