This week we talk to Clark Dietz’s own Archana Raju, staff engineer and resident water and wastewater treatment expert, about her attendance at the Water Environment Federation's Technical Exhibition and Conference, more commonly known as WEFTEC, the week of October 5-9, 2020. Described as the “world’s most comprehensive gathering of water quality professionals and thought leaders,” WEFTEC is a must-attend for those in the water and wastewater industry. Archana was kind enough to share some insights from the week.
ABOUT THE CONFERENCE
Last year I attended WEFTEC as an in-person conference. Traditionally it is a one week all in-person event that was completely redesigned this year through the WEF Connect platform. It is mainly filled with technical sessions, keynote events, roundtable discussions, etc., designed to inspire and connect water professionals and the industry from all over the world during these unprecedented times.
You have the policy administrators, your utility leaders, and industry professionals such as me, the process engineers. On the product side, big companies present new tech for wastewater treatment with exhibits. Traditionally, they have in-person exhibits with product demonstrations by all the different vendors to allow you to interact with and learn about the new technologies. But this year, it was different in that you’d attend a presentation with a product demonstration.
EPA’S ANDREW WHEELER DISCUSSES STREAMLINING
THE GRANT APPLICATION PROCESS
I attended a keynote address by Mr. Andrew Wheeler, the EPA Administrator, speaking on the public policy side. He talked about the new American Water Works initiative that aims to partner with communities that are facing challenges and workforce shortages in the water infrastructure area. This program will assist in bolstering education and recruiting more professionals to meet future demands.
TRACKING COVID-19 THROUGH WASTEWATER SURVEILLANCE
There was a lot of pandemic-related information, and its impact on our sector was presented. One thing that caught my attention was how COVID-19 can be detected through wastewater, and how by using wastewater we can monitor the virus itself. I learned there is currently a lack of consensus in the methodology for wastewater surveillance, and it is now based on typical approaches such as immuno- and antigen-based methods. Wastewater surveillance has important potential in trend tracking, identifying hotspots, sequencing genomes, and understanding how the virus evolves. An important note is that whatever information we get from wastewater analysis is complementary, enabling us to monitor large populations and understanding the infection. It also will give the public confidence while helping us to understand the leading indicators of infection in a large community.
You can quantify the target, in this case, it would be SARS-CoV-2. By using this, we would be able to predict the virus, even before it propagates.
They used two examples of how this sort of sampling is applicable, like in the Netherlands. A COVID case was detected in the wastewater, even before the case was reported. Similarly, at Arizona University they did wastewater sampling when they reopened the campus and were able to detect the presence of the virus from the wastewater. They then did testing of the students and realized someone was infected.
This type of testing is especially helpful for detecting those who have COVID but are pre- or asymptomatic. This testing also helps our understanding of the virus in the wastewater and learning what applications would be beneficial.
UV-C LED DISINFECTION TECHNOLOGY
I also attended one session on the new UV-C LED disinfection technology. Typically, there will be disinfection of the wastewater after the secondary treatment process to kill pathogens such as E. coli and fecal coliform and to meet the effluent permit limit. For disinfection, we usually employ chemical disinfection methods or UV. Through a lot of studies that I have seen, UV disinfection is the most cost-effective. But the new UV-C LED technology that is currently being piloted and under demonstration shows that it can achieve basic disinfection compared to traditional systems, but it is also effective on COVID. While this technology is still under demonstration, they are saying that by 2026 this technology will achieve and even surpass the level of output of the traditional systems that we have, the medium and the low-pressure lamp UV systems. I think this new technology will be great because it could overcome some limitations of current UV systems, such as the mercury in UV lamps and the high power consumption of the current bulbs.
AquaNereda: THE "BREAKTHROUGH TECHNOLOGY OF THE DECADE"
I learned about an emerging technology called the AquaNereda system, which was touted as the breakthrough technology of the decade. This technology is based on the aerobic granular sludge technology, and it's a very innovative biological wastewater system to provide advanced treatment of wastewater. Many U.S. plants have variations of a conventional activated sludge system, where aeration basins remove BOD, TSS, ammonia, and sometimes total phosphorous and nitrate. In AquaNereda technology, everything happens in this one reactor, eliminating the need for aeration basins, clarifiers, selectors, separate compartments, pumping stations, repumping stations, return activated sludge or sludge pumping stations. It was cool to see how the single reactor can achieve all the processes with a very simple, one-reactor concept that has a cycle-based batch operation.
"In AquaNereda technology, everything happens in this one reactor, eliminating the need for aeration basins..."
As the name suggests, aerobic granular sludge, it consists of granules with a layered microbial community that has great settling property. This biomass is fed in the first phase, and the reactor creates ideal conditions to develop and maintain stable growth. The layered zones in the granule, such as the aerobic and anaerobic zone, allow for simultaneous processes to take place in the biomass, thus achieving enhanced biological phosphorus reduction and simultaneous nitrification and denitrification.
The main thing to note is that you have significant energy savings because of reduction in aeration requirements as well as elimination of pump systems. You also have the time cycle flexibility and a lot less footprint. Overall, there are about 80 aerobic granular sludge treatment plants in place worldwide. It would be transformational for the United States to start adopting this technology more. I think there are a couple planned for construction in 2021. AquaNereda’s U.S. partner Aqua-Aerobic Systems has a demonstration aerobic granular sludge plant in Rockford, Illinois and has piloted demonstration units in several U.S. locations.
Thank you for your time, Archana. We appreciate your take on the WEFTEC conference and some exciting innovations we can look forward to in the industry in the months ahead.