High-Salinity Concentration · PFO

Pressurized Forward

osmosis

PFO concentrates high-salinity feeds. Hydraulic pressure works with a permeate-side osmotic solution, cutting the pressure the system has to overcome.

Request a PFO Feed ReviewExplore Brine Concentration
Trevi pressurized forward-osmosis membrane element from the NAWI trial in California
A Trevi PFO membrane element after service on high-recovery feed, withdrawn during the NAWI trial in California.
PFO · Hydraulic + osmotic assistance

How PFO Extends the Operating Window

A permeate-side osmotic solution narrows the gap; feed pressure moves the water across.

01

Prepare the feed

Control scale, fouling, and the operating window before the membrane.

02

Set the balance

Tune pressure and the permeate-side solution within equipment limits.

03

Separate the streams

Transfer water into the osmotic stream as the feed reaches its concentration endpoint.

Chemistry
Salinity · Hardness · Silica · Organics
Operating case
Flow · Temperature · Pressure · Variability
Protection
Pretreatment · Cleaning · Interstage control
Endpoints
Product target · Residual route

Recovery, flux, energy use, and final concentration are feed-specific.

Submit Feed Data
Project sequence

Defining the Feed and Operating Window

PFO runs as one stage in a complete treatment train.

  1. 01

    Characterize

    We characterize feed chemistry at the actual operating pressures and recoveries. Scaling and fouling risk follow the concentrate, not feed TDS alone.

  2. 02

    Condition

    Select the pretreatment needed for the target concentration factor.

  3. 03

    Set the balance

    Establish hydraulic and osmotic conditions within operating limits.

  4. 04

    Transfer and stage

    Monitor performance and adjust staging against test data.

  5. 05

    Finish and route

    Polish recovered water and route the concentrated residual.

Published sources

Pilot Results and Patent Scope

California multi-site pilot

Integrated treatment trains across five sites

Cambria CSD's 2026 summary describes PFO following two alternative upstream softening approaches.

PublishedProgram
Five California pilot sites
Cambria CSD · 2026
PublishedReported final brine
100,000–150,000 ppm across the integrated pilot trains
Cambria CSD
AttributedPreferred Cambria train
EDM softening · PFO · final RO polishing
Cambria CSD agenda packet

Results reflect integrated trains with upstream softening, not standalone PFO.

Published patents

Osmotic-pressure-assisted membrane and module

PublishedU.S. Patent
11,839,853
Issued 2023

A patent documents the invention, not project performance.

Review Your Feed
Feed review · Chemistry · Flow · Temperature · Target

Provide the operating basis for a PFO review. Trevi will define the next test.

Request a PFO Feed ReviewExplore Brine Concentration