The Ahrtal in the German states of North Rhine-Westphalia and Rhineland-Palatinate continues to grapple with the devastating aftermath of the July 2021 flood. Particularly in the initial weeks, substantial efforts were required for this endeavor.
From left: Peter Link (Account Manager, Aerzen Rental) and Sascha Becker (Operations Manager of Sinzig wastewater treatment plant, AZV Untere Ahr) in front of the mobile rental solution that ensures the operation of wastewater treatment in Sinzig. Image Credit: Aerzener Maschinenfabrik GmbH
It was crucial to swiftly restore the local infrastructure, with a particular focus on wastewater treatment. The Sinzig wastewater treatment plant, situated right along the banks of the Ahr river, relied on mobile rental solutions to expedite the resumption of operations.
The Ahrtal has always been a tourist hotspot, boasting lush green vineyards, Rhine river shipping, historic castles, and numerous other attractions. When the 2021 flood wreaked havoc on this picturesque area, residents worked diligently to clear the aftermath promptly.
Their efforts have paid off, and today, the Rhenish region has once again become a sought-after destination for outings. However, observant visitors will notice that the event of the century has left its imprint. For instance, many new buildings now incorporate an open ground floor, a precaution against potential floods.
The Consequences of the Flood are Still Felt in the Ahrtal Today
The Ahr flood also caused damage to the municipal infrastructure, and its effects are still evident today. Multiple wastewater treatment plants suffered harm from the deluge, some to an extent where repairs were no longer feasible.
One of the most formidable challenges fell upon the Abwasserzweckverband (AZV) Untere Ahr, an organization responsible for handling and purifying wastewater from its six founding communities: Altenahr, Bad Neuenahr-Ahrweiler, Grafschaft, Bad Breisig, Remagen, and Sinzig.
The Sinzig wastewater treatment plant, designed for 115,000 population equivalents (p.e.), faced severe damage due to its location directly along the banks of the Ahr. While this location had initially been deliberately chosen, it became a liability during the flood.
Due to the location of the plant, the wastewater from almost all communities did not have to be pumped but could flow freely to the plant. However, the floodwaters submerged the entire wastewater treatment plant, with the administration building submerged beneath one meter of water.
Upon entering the site on July 15, 2021, a day after the flood, the operations staff quickly realized that rectifying the immediate flood consequences would be a lengthy process. Simultaneously, they recognized the plant's critical infrastructure status, necessitating a swift return to operation. Consequently, urgent assistance was imperative.
The AZV aimed to restore the plant's functionality as promptly as possible. Due to its vulnerable location, the possibility of a complete reconstruction remained uncertain, leading to an initial decision to refrain from acquiring new equipment.
Within a matter of days, as cleanup efforts commenced, the verdict was clear: a rental solution was the way forward.
At the centre of Aerzen Rental’s mobile co-solution is a container with three turbo blowers. Each blower supplies oxygen to anaeration basin as needed. In addition to mobile aerator plates, the rental solution consists of a container for the process air (blue) and a container for the control technology (white). Image Credit: Aerzener Maschinenfabrik GmbH
Fast Commissioning with a Mobile Rental Solution
Once the basin was cleared, Peter Link proposed a solution involving mobile aerator plates and a BVS 5500 GM 90 S positive displacement blower with a maximum airflow of 5000 m³/h as the optimal choice.
The turbo blowers of the mobile rental solution are state-of-the-art. If required, they can be taken over and permanently installed at the new location of the future wastewater treatment plant. Image Credit: Aerzener Maschinenfabrik GmbH
“With this technique geared to the oxygen needs of the pool, we were able to ensure that operations could be resumed as quickly as possible,” Peter Link says.
With his team, he devised the specifics while the basin underwent clearing in Sinzig. Following that, the flood-damaged biology had to be entirely reconstructed, and the purification stage had to be restarted. Simultaneously, Sascha Becker and his team handled the cleaning of the other basins.
The initial clearing of the aeration basin saw the installation of the mobile aerator plates from Aerzen Rental. These were connected to the BVS 5500 rental package through portable piping.
As a comprehensive solution, Aerzen Rental provided the blower in a container, complete with soundproofing, a special frame, and full electrical equipment, including a frequency inverter.
This plug-and-play solution was set up outdoors, right beside the basins, enhancing flexibility while minimizing piping and installation expenses. Control was established via Profibus, operating independently of the plant's original technology.
“Our solutions can be connected to the existing stock without any problems, but in Sinzig the flood had destroyed the control system as well as the rest of the technology,” Peter Link explains. “That's why we set up another container next to the blower, where completely new control cabinets were installed.”
In August 2021, a mere few weeks following the flood, the entire AERZEN solution was implemented. The wastewater treatment plant team was then able to establish the biology and provide the basin with the required oxygen.
“After inoculation, the biomass in the basin needs about three weeks until it is actively working,” explains Sascha Becker. “So while the biology was coming in, we were preparing the other basins.”
These basins were subsequently outfitted with new aerator candles. It was not until December 2021 that all the basins were fully prepared for use.
“At that point, we had enough biomass available to distribute among all the basins,” the Production Manager recalls.
To reliably provide oxygen to all three basins, the blower container had to be adjusted to meet the overall demand. Peter Link and his team returned to the site: Less than four months after the initial commissioning, the container was disassembled and replaced with a new rental solution.
Since then, three Aerzen Turbo G5plus blowers—consisting of one AT 200 and two AT 150—have been operating in the wastewater treatment plant in Sinzig. Each of these compact, efficient turbo blowers supplies one basin with oxygen as required. When the optimal oxygen levels for operation are achieved, the fans are idled to conserve energy.
The piping of the rental solution is mobile. Each of the three basins of the biological purification stage is connected to a turbo blower which supplies the oxygen. Image Credit: Aerzener Maschinenfabrik GmbH
Efficient Solution for Present and Future
“Most of our staff experienced the flood not only at the facility but also privately,” recalls Sascha Becker. “During the work to remove the flood damage, you had to blank out all that and it just worked,” says the Production Manager.
The reliability of Aerzen Rental's rental solution has simplified many aspects of the operations.
“We had regular contact with AERZEN, exchanged ideas, and optimized the technology at some points. After the set-up, the plant has been working exactly as it should.”
“This job was not a standard one for us either - just like none of the projects in the Ahrtal after the flood,” emphasizes Peter Link.
The reason the work proceeded so smoothly is that Aerzen Rental's rental park is consistently tailored to meet demand.
The control system for the turbo blowers is housed in a separate container. As the technology of the wastewater treatment plant was destroyed by the flood, the control of the mobile rental solution runs separately. Image Credit: Aerzener Maschinenfabrik GmbH
“About 40 percent of our customers are municipalities that have to ensure the operation of their wastewater treatment plants. We have the appropriate equipment available for this, which we can provide immediately. So we were able to help quickly in Sinzig, too,” Peter Link explains.
Looking ahead, AZV Sinzig plans to construct a new wastewater treatment plant site, positioned seven meters higher than the previous location, and designed to serve over 180,000 people, replacing yet another facility that was destroyed in the flood.
“During the planning process, care was also taken to ensure that the new site was not located in the floodplain of either the Ahr or the Rhine,” adds Sascha Becker.
Nonetheless, not everything must be created from the ground up; AERZEN turbo blowers can be relocated and permanently installed when the new wastewater treatment plant becomes operational. If necessary, the rental solution can become a permanent fixture.
“So far we are thinking about buying, after all we have good experience and the rented turbos are state of the art,” says Sascha Becker.
At the same time, the flood taught him that you never know what the future holds: “There will be a lot of rethinking, after all there is always flooding.”
Peter Link's team consistently adjusts its services to meet evolving needs. Whether it is an emergency, a conversion, or a new construction, with over 150 rental machines, the provider ensures that customers can maintain their operations swiftly, safely, and efficiently at all times.
This information has been sourced, reviewed and adapted from materials provided by Aerzener Maschinenfabrik GmbH.
For more information on this source, please visit Aerzener Maschinenfabrik GmbH.