NF-RO-FO

PILOT PLANT FOR STUDYING COMBINATIONS OF FORWARD OSMOSIS AND REVERSE OSMOSIS/NANOFILTRATION

The plant has three different units that can be coupled in different ways between them: (i) Forward Osmosis; (ii) Reverse Osmosis/Nanofiltration; (iii) Microfiltration (Figure 87). The Forward Osmosis (FO) unit uses 12 hollow fibre modules (Aquaporin HFF02) 0.2 mm long with 2.3 m2 total membrane area each one, operating in counter-current flow, inside-out, laid out in a flexible rack that allows combining them in series or parallel configuration. The nominal flow rate is 3.6 m3/h. The Reverse Osmosis (RO) unit has one 8” and two 4” pressure vessels that can be connected in series or parallel, each of which able to host four membranes. The nominal flow rate is 3 m3/h and the pumping system can work at different pressures up to a maximum of 80 bar (RO)/16 bar (NF). Finally, there is an MF unit with 3 m3/h nominal flow rate. The installation is completely monitored with pressure sensors,
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conductivity and flowmeters, and it is designed in a flexible way regarding the interconnection of the units so that FO can be used as a pre-treatment for RO, or NF can be used in combination with FO, and even the FO can be used in PRO mode using the pumping system of the RO unit.