Platform on civil engineering, underground infrastructure, energy, construction equipment & construction machinery
Purification sounds so relatively simple, but behind it is a world of modular construction, clever techniques and collaboration. 'Only that smell never gets used.'
The good news is that once the construction phase is over and the treatment plant is fully commissioned, the odor experience will also diminish. But then project leader Jochem Seghers will have finished his project, which he is pulling on behalf of Mobilis and Croonwolters&dros. When he started the job he was far from sure of his case, now he is brimming with self-confidence. From June 1, the WWTP will run independently: 'You're going to build a treatment plant within a year,' I was told. Yes, yes, I thought. But it has worked out. This is really spectacular.'
Special features include working together in a construction team during implementation, the use of biological Nereda for purification and the Verdygo principle that makes construction and installations almost entirely modular and sustainable. There is also great attention to the environment. For example, the post-treatment of the concrete floor of the water basins is based on seaweed (Delft Green) .
Technical manager Ruud Paridaans of the Waterschapsbedrijf Limburg (WBL) is delighted with the result and predicts that this concept will be adopted by other water boards. 'The water treatment plant is more flexible, faster to build and more pleasant and smart to maintain. Moreover, the treatment process itself also runs very efficiently through the application of Nereda technology. That adds up quickly.'
Waterschapsbedrijf Limburg, together with Mobilis, Croonwolters&dros and Tauw, picked up the design phase. 'We are convinced that you have to use knowledge from the market. We have in-house expertise, but the executing parties also bring a lot of experience and ideas. By combining that, you get a smarter and better design,' Paridaans explains.
The water board has selected three construction consortia for a framework contract to carry out several projects, both in Weert, Stein and Panheel. In Panheel and Stein, Mobilis is building two wastewater treatment plants. In Panheel, Mobilis is working with Croonwolter&dros (CMC Waterprojecten Limburg) and Eliquo. In Stein, CMC is working with Engie and Eliquo. At Panheel there is now - as in Stein - a completely new treatment plant.
We walk from the construction site to the four basins. What is striking is that everything is above ground. In front of the basins runs one big shiny piping cacophony with a long bridge above it running along the basins. Below that are several blue containers, separate modules containing the installations.
The idea of one pipe line is already a lot more efficient. The whole thing is imposingly large, but it takes up only a third of the surface area compared to the old plant, which is spread much more here and there across the site and requires many more tanks and basins to treat the "sewage.
'Look, we start with one buffer tank then two Nereda reactors, followed by that relatively small sludge tank,' Paridaans points out. 'The clever thing about the Nerada concept is that it uses granular sludge with good settling properties. Completely organic. By now a proven concept,' Seghers adds. 'Before the sewage flows into the tanks, grids take out all the coarse particles, including the sand. In the Nereda tank, the purified water can settle and the sludge sinks to the bottom. At the surface, clean water remains. It's really that simple.
Of a traditional construction site, there is really no longer any question. The construction fences and shack are still standing, but the four round tanks are in full operation and the water is churning and bubbling. The first tank is covered with a large tarp. 'That's mainly to stop the smell - it's mostly pee and poo after all - and to prevent leaves from falling into the water.' Here and there a shovel and a dump truck are still driving, but the work is as good as finished. 'Soon we can start demolishing the old treatment plant. With that, you want to wait until it is 100 percent certain that the new treatment plant is running,' Seghers explains.
Seghers and Paridaans liked working in a construction team. 'You make use of each other's knowledge and expertise, but you also avoid a lot of fuss about financial setbacks and risks with a construction team. Of course we have discussions about the approach, the planning and the risks. That is inevitable with such a large project, but in a pleasant tone and with 'best for project' at the forefront," Paridaans has experienced.
Three disciplines must work together: civil, mechanical and electrical. That alone creates challenges. The result is a modular and compact whole. The tight schedule also proved to be the biggest challenge in this project. 'And Corona was also a constant concern, which meant that people still sometimes dropped out unexpectedly,' Seghers says. 'But safety always came first and we managed to carry out the project without any accidents. Surely that is also worth mentioning,' Paridaans adds.
Project leader Ad van Oers of Croonwolters&dros is above all delighted with the modular approach that has been put in place entirely above ground. 'All the technology in the Verdygo modules has been built in a shielded environment within factory walls. The individual elements are easily accessible and identical and interchangeable from the outside. Moreover, you can replace such a module within a few hours if a blower or pump fails. You then remove it from the system, causing minimal disruption to the purification process. That is extremely efficient compared to more traditional systems.' Even during the design, a circular approach was carefully considered. Almost all modules are reusable and interchangeable.
In Panheel, Limburg, the sewage from surrounding municipalities comes together. For years, a treatment plant of Waterschapbedrijf Limburg has been running there in the Heggerstraat retrospectively. The old installations are still in use - 'we're still running synchronously for now'- but that won't last long. Project leader Ellen van der Bend has supervised the test phase over the past few months, including the transition from the old to the new treatment plant. Water quality is tested every day, but in the start-up phase it was much more frequent.
'Surprisingly quickly, the bacteria coalesced well and did their job. Within two weeks, the treated water from the new plant was already cleaner than the old one. And that was only halfway through starting the Nereda process. That really gave a buzz. The testing was downright exciting. Each discipline tested the components separately, but the system also has to work when everything is connected together. For the start-up phase, we had 34 trucks with sludge come from the water treatment plant in Weert," she recalls of the exciting transition.
'We started with a small backlog of work, but the commissioning went smoothly and quickly beyond expectations. The pressure was high and the fuses a little shorter. But when it all works so well, everyone is proud and enthusiastic. We will be completely ready before the construction period. Both the water treatment plants in Panheel and Stein will be operational before the construction period. The official handover is scheduled for later this year.
Project details water treatment Panheel
Installations WWTP
Louwers Mediagroep
Schatbeurderlaan 6
6002 ED Weert
© 1987 - 2025 Louwers Media Group.
