RO membrane scaling at an Eindhoven coatings factory
RO membrane scaling was cutting permeate flow at a coatings factory in Eindhoven, Netherlands, which uses reverse osmosis to make demineralised water for its production process. RO system 1 runs at 85% recovery with 2.0 m³/h of concentrate recirculated, and after a membrane clean in May 2018 its permeate flow fell from 5,600 to 3,500 L/h in about three months. After the next clean in September 2018, a HydroFLOW® P100 was fitted to the RO 1 feed line, with an HS40 ahead of the prefilter. The decline in permeate flow was then around 70% slower, flow was still 4,400 L/h after four weeks, and the customer bought both units.
The Challenge
- RO membrane scaling caused rapid permeate-flow loss between cleans
- Permeate flow fell from 5,600 to 3,500 L/h in about three months
- The RO system ran at 85% recovery
- 0 m³/h of concentrate was recirculated
The Solution
- Units installed: one HydroFLOW® P100 and one HS40
- Installation points: P100 on the RO 1 feed line, HS40 ahead of the prefilter
- System: RO system 1, making demineralised water at 85% recovery
- Installed: September 2018, after a membrane clean
To compare like with like, RO membrane scaling was measured from the same starting point both times: a fresh membrane clean. Permeate flow was logged after the May 2018 clean with no treatment, then again after the September 2018 clean with the units in place, and a linear trend was fitted to each period to compare how fast the flow fell.
