393 High Recovery Reverse Osmosis (HRRO): Expert Guidance on Optimizing System Performance

We’re focusing on High Recovery Reverse Osmosis (HRRO) with insights from Ken Robinson, Director of North America Application & Sales at Avista Technologies. With over 40 years of experience in membrane technology, Ken sheds light on how HRRO is transforming water treatment and tackling industry challenges. Here are the key highlights from our conversation.

What is Reverse Osmosis (RO)?
Ken describes reverse osmosis as a method for rejecting dissolved minerals and macro-organics from water. He stated, “Today’s systems, most of them are using what they call a thin film composite membrane, which are categorized into seawater, brackish, and low-energy membranes, along with an offshoot called nanofiltration.” These systems achieve remarkable efficiency, with a rejection rate of around 99%, leaving only a minimal amount of dissolved minerals in the purified water.

What is High Recovery Reverse Osmosis (HRRO)?
HRRO is designed to maximize water recovery and minimize waste, making it a game-changer for water treatment. According to Ken, “40 years ago, recovery limitations were dictated by the chemistries. Today, advances in antiscalant technology allow for much higher recovery rates.” This technology takes the concentrate from conventional RO systems and processes it further, increasing efficiency and sustainability.

Industries Leading the Way
Initially adopted in industrial settings, HRRO is now gaining traction in sectors like municipal water treatment, food and beverage production, and power generation. Ken emphasized that “the growing focus on sustainability and regulatory compliance is driving broader adoption of HRRO systems.”

Ensuring Successful Operations
To ensure HRRO systems function optimally, it’s crucial to define feedwater quality parameters and anticipate variability. Ken stressed the importance of training operators, noting, “There always seems to be a disconnect between applications and salespeople developing ideas. Misunderstandings arise when people don’t understand the behavior of water as it concentrates.”

To effectively tackle any challenges that arise, Ken recommends the following steps for operators:

1. Define Feedwater Quality Parameters: Establish clear benchmarks for feedwater quality, including turbidity, pH, total dissolved solids (TDS), and any specific contaminants. This baseline will help identify any deviations that may affect system performance.
2. Implement Regular Monitoring: Operators should capture data at regular intervals. This includes monitoring system pressures, flow rates, and recovery rates. Keeping an eye on these metrics will allow operators to identify trends and detect any anomalies early on.
   
3. Normalize Collected Data: Regularly normalize the collected data to account for variations in operating conditions. By adjusting the data for factors such as temperature or seasonal changes, operators can gain clearer insights into system performance and efficiency.
4. Train Operators on Water Behavior: Provide comprehensive training for operators that focuses on understanding how water behaves during the concentration process. As Ken pointed out, “water is very predictable in how it behaves,” so operators need to recognize the symptoms of potential issues and understand their causes.
5. Foster Open Communication: Encourage collaboration among team members, especially between operators and technical support staff. Ken highlighted that insights often emerge from frontline staff who have firsthand experience with system operations.
6. Conduct Root Cause Analysis: When problems arise, implement a structured approach to root cause analysis. This should involve gathering all relevant data, discussing operational practices, and reviewing system design. Engaging the team in this process can uncover issues that might be overlooked by individuals working in isolation.
7. Adapt and Adjust: Finally, remain flexible and ready to adapt operational strategies based on the data insights and root cause analysis findings.

By following these steps, operators can optimize HRRO system performance, improve efficiency, and ultimately reduce waste.

Signs of a Successful Cleaning
Ken Robinson shared valuable insights into the cleaning process, emphasizing the role of pre-treatment: “Pre-treatment is king in dictating the frequency,” he said, noting that surface water applications tend to require more frequent cleaning than well water systems.

Ensuring that the cleaning process has been successful is key to maintaining high efficiency in HRRO systems. According to Ken, operators should check a few critical parameters post-cleaning:

1. Performance Recovery: A successful cleaning will restore the system’s flow rates and pressures to their baseline levels. Operators should monitor permeate flow, pressure differentials, and salt rejection rates to confirm the system is operating efficiently after cleaning.
2. Normalized Data Comparison: Ken advised that operators should regularly normalize the system’s data, both before and after cleaning, to get an accurate view of performance. If system performance remains suboptimal post-cleaning, it could indicate incomplete cleaning or deeper issues within the system.
3. Visual Inspection: While much of the data will be analyzed digitally, a hands-on inspection of membranes and pre-treatment systems can also reveal residual fouling. If membranes appear visually clean and performance metrics align, it’s a good indicator that the cleaning was successful.

By consistently tracking and analyzing these factors, operators can extend membrane life and prevent performance issues from recurring.

Future RO Innovations
Ken highlighted the development of thin-film composite membranes as one of the most impactful advancements in RO technology. These membranes have made it possible to push systems to new limits, achieving higher recovery rates while maintaining durability.

Looking ahead, zero liquid discharge (ZLD) systems—which aim to eliminate waste entirely—are on the horizon. As regions face water scarcity and stricter regulations, Ken sees ZLD playing a vital role in the future of water treatment.

Conclusion
HRRO is transforming the water treatment landscape by driving efficiency and sustainability. By leveraging the latest advancements and understanding the challenges, operators can optimize performance and reduce waste, helping clients meet both regulatory and environmental goals.

Stay curious, stay informed, and keep scaling up your knowledge!

Timestamps
07:33 – Trace Blackmore invites everyone to join the global community of Scaling UP! Nation members and explains how to subscribe to the podcast
08:51 – Upcoming Events for Water Treatment Professionals
13:18 – Interview with Ken Robinson about RO
59:40 – Drop by Drop with James McDonald 

Connect with Ken Robinson
Phone: +1 440 251 7390
Email: [email protected]
Website: https://avistamembranesolutions.com/
LinkedIn: https://www.linkedin.com/in/ken-robinson-00b59514/
Read or Download Ken Robinson’s Press Release HERE