99% Membrane System Recovery on Scaling Cooling Tower Blowdown

Removing the need for an evaporation pond, saving water, and reducing-GHG emissions

November 16th, 2020

First-of-its-Kind Ultra-High Recovery Membrane System

Reverse osmosis-based brine concentrators are reaching new performance levels not seen before. Saltworks is pleased to report that a substantial pilot plant is currently demonstrating 99% freshwater recovery on cooling tower blowdown (CTB). CTB enters the treatment plant nearly saturated in scaling ions, which would limit recoveries to 80% for RO plants—not good enough to solve this site’s water balance needs.


How did the plant reach 99% recovery? We started with a conventional 80% recovery solution and then bolted on our turbo-chargers: Saltworks’ BrineRefine and Saltworks’ XtremeRO, which utilizes Nitto HYDRANAUTICSTM PRO-XP1 reverse osmosis membranes.


BrineRefine removes scaling ions, enabling reverse osmosis (RO) to reach its osmotic pressure limits without scaling or fouling. With the scaling ions removed and Nitto-Hydranautics membranes inside, XtremeRO concentrates the water—first at 1,200 psi (seawater RO) and then at 1,800 psi (UHP-RO). The 99% permeate can be reused by the client, which enables the industrial facility to drastically reduce river water withdrawal in a drought-sensitive region. The ultra-high recovery with 1% brine prevents the need for a more costly and energy-intensive thermal evaporator, potentially controversial evaporation pond expansions, or GHG-intensive trucking of wastewater.

Photo of a Saltworks engineer working on a 99% recovery membrane pilot plant
A Saltworks engineer operating the plant on-site
A photo of the outside of a UHPRO pilot plant that achieved 99% recovery of cooling tower blowdown
A containerized plant that is ready to ship

Saltworks has successfully demonstrated UHP-RO on various customer applications, including mining waters, factory wastewater, ion exchange regeneration waste, and cooling tower blowdown. This pilot plant, jointly developed with Nitto Hydranautics, is packaged and ready-to-go in two 40’ ISO shipping containers for portability and ease of site setup. Full-scale systems including UHP-RO are being produced at Saltworks’ advanced manufacturing plant in Richmond, BC, Canada.

Photo of a UHPRO pilot plant operating on cooling tower blowdown
An on-site plant that is treating cooling tower blowdown at a power station

We would love to help you achieve your water goals. Whether you seek conventional or advanced solutions, we can help. Contact us to learn more about treating cooling tower blowdown or other challenging waters. Let us know if your team is interested in a webinar to learn about the latest in advanced membrane systems, selective ion removal, or zero liquid discharge (ZLD).

About Nitto

Nitto is Japan’s leading diversified materials manufacturer. Founded in 1918, Nitto’s strength is the ability to add diverse functionality to sheets, films and other materials using core technologies such as polymer synthesis, adhesion, and coating technologies. The group offers high value specialty products worldwide including optical films for liquid crystal displays, automotive materials, reverse osmosis membranes for desalination and transdermal drug delivery patches. Hydranautics is a part of the Nitto Group and one of the global leaders in the field of integrated membrane solutions. Hydranautics offers complete membrane solutions like reverse osmosis, nanofiltration, ultrafiltration, and microfiltration for water, wastewater and process treatment and applications. For further information on Nitto and Hydranautics, kindly visit our website: www.nitto.com and www.membranes.com.

About Saltworks

Saltworks Technologies is a leader in the development and delivery of solutions for industrial wastewater treatment and lithium refining. By working with customers to understand their unique challenges and focusing on continuous innovation, Saltworks’ solutions provide best-in-class performance and reliability. From its headquarters in Richmond, BC, Canada, Saltworks’ team designs, builds, and operates full-scale plants, and offers comprehensive onsite and offsite testing services with its fleet of mobile pilots.

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