Case Study from HydroFLOW France
Centrifuge polymer reduction at Mainvilliers
Centrifuge polymer reduction was the aim when AQUALTER evaluated HydroFLOW® for sludge dewatering at the Mainvilliers wastewater treatment plant, which serves Chartres Métropole. Polymer is a constant cost in mechanical dewatering, and cutting it risks poorer flocculation and wetter cake. The site’s three centrifuges allowed a treated line to be compared with an untreated one. One HydroFLOW® i190 was tested at two positions, and the upstream position on the 140 mm PVC line was chosen. Polymer use fell by 19.7%, and at equal settings the treated cake was 20.68% dry against 18.31%, with centrate suspended solids halved.
The Challenge
- Centrifuge polymer reduction was needed to cut a constant dewatering cost
- Reducing polymer can compromise sludge flocculation and cake dryness
- Centrate quality had to stay low in total suspended solids
- Untreated cake was damp and putty-like
The Solution
- Unit tested: one HydroFLOW® i190
- Installation position: 140 mm PVC line upstream of the polymer pump
- Positions tested: two on the centrifuge line, with the upstream one selected
- Comparison: treated centrifuge 2 against untreated centrifuge 1 at matched settings
For centrifuge polymer reduction without losing cake quality, the i190 was tried at two points on the centrifuge line. The upstream position on the 140 mm PVC pipe performed better and became the preferred configuration. Treated and untreated centrifuges were then run at equal settings, so cake dryness and centrate quality could be compared directly.
