Garver, LLC advances zero liquid discharge research
Enhancing circular economy research with flow and liquid analysis
Garver’s Water Business Line was awarded the United States Bureau of Reclamation’s (BOR) Pitch to Pilot Research Project, allowing their research team to embark on a journey to do something that is rarely accomplished in the research community: vetting a zero liquid discharge (ZLD) treatment train to recover the saline cooling tower blowdown. If successful, the project would prove how their pilot train prevents the salt from entering the sewer system.
Members of the research team give a tour of the Pitch to Pilot research trailer to members of the DOE, NREL and Lawrence Berkley Labs.
ZLD technologies and systems results
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Following field testing using Endress+Hauser and Rockwell Automation instrumentation, Garver discovered that its EC + CLAR + MF + RO with VAED concentrate treatment train consistently met its water quality goals in a ZLD configuration.
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Garver met water quality goals without any chemical pretreatment under start-stop operation (for up to four months of downtime without the addition of membrane preservatives), while consistently achieving > 99% TDS reduction.
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Garver will continue focusing on opportunities to address critical topics like salt accumulation in watersheds, and instrumentation and technology from manufacturers like Endress+Hauser and Rockwell Automation will continue to play a pivotal role.
Challenges in ZLD water treatment
Fouling of RO membranes is one of the most common challenges, requiring intense chemical pretreatment and periodic chemical clean-in-place maintenance. Not properly designing, operating and maintaining an RO system can lead to high energy intensity and a high likelihood of failure. The main driver for the research was developing a disruptive desalination treatment train that requires less chemicals and energy than commercially available technologies.
Latest innovations in ZLD water treatment
With the blowdown’s sizeable effect on watershed health and at a time when water reuse is at the forefront of national and global discussions, Garver began looking for opportunities to research and create a system to improve saline blowdown from commercial and industrial cooling towers. This led to the collaboration with Endress+Hauser and Rockwell Automation to provide the necessary instrumentation and technology to trend treatment efficacy and energy intensity.
How does ZLD technology work in wastewater treatment?
ZLD technology treats wastewater by removing all liquid, leaving behind only solid waste or recoverable materials. The process typically involves multiple stages, such as clarification, filtration, reverse osmosis (RO) and evaporation or crystallization, to concentrate and recover water while isolating salts and other contaminants. In Garver’s pilot system, advanced instrumentation from Endress+Hauser and Rockwell Automation helped monitor treatment efficacy and energy intensity.
What are the latest innovations in ZLD water treatment?
Recent innovations in ZLD water treatment focus on improving recovery rates, reducing energy consumption and minimizing chemical use. Technologies like chlorine-tolerant membranes, electrodialysis reversal (EDR) and hybrid membrane systems are making ZLD more efficient and scalable. Garver’s pilot system demonstrates how advanced instrumentation and smart design can achieve >99% TDS reduction without chemical pretreatment, even under intermittent operation.
Which description best defines circular economy?
The circular economy is an economic model focused on minimizing waste and maximizing resource reuse. In water treatment, this means recovering and reusing water, energy and materials rather than discharging them as waste. Garver’s ZLD pilot project exemplifies this by preventing saline blowdown from entering the sewer system and enabling water reuse, supporting watershed health and long-term sustainability.
